Dissertações/Teses

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2023
Descrição
  • JULIO CESAR MENDES LOBATO
  • Interactions of Carbon Nanotubes and Graphene Oxide Quantum Dots with external structures of SARS-CoV-2 via Molecular Dynamics and Docking

  • Orientador : ANTONIO MAIA DE JESUS CHAVES NETO
  • Data: 02/06/2023
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  • The ability of interaction between carbon nanotubes and graphene oxide (GO) quantum dots and SAR-CoV 2 virus proteins was evaluated. In a first simulation, the ligands used were single-walled carbon nanotubes and the receptors that are the main structures of the virus: the envelope protein (E-pro), the main protease (M-pro) and the Spike glycoprotein (S-gly). For this, molecular modeling of docking and molecular dynamics was used. Molecular dynamics provided information on the mean square deviation of atomic positions between 0.5Å and 3.0Å. Molecular dynamics showed that the zigzag nanotube obtained a better Gibbis energy (ΔG) which corresponds to the free energy of binding between the nanoparticles and the protein targets presented values: - 9.48, - 9.98 and - 10.08 kcal/ mol for E-pro, M-pro and S-gly respectively, the mean squared deviation values of the atomic positions remained more stable for this nanotube species, indicating that it has a high probability of binding to the active site residues of the macromolecules. Molecular couplings and binding free energy showed that the residues of the S-gly active site strongly interacted with the NTCPUs, registering values of: -112.73, -94.38, -80.49 kcal/mol for the zigzag, chiral and armchair, respectively. In a second step, using almost the same methodology as the previous one for the ligands, however with the graphene oxide quantum dots smaller than 20 nm and interacting only with the receptors of the spikes of three different strains: S-gly-Omicron , S-gly-Kappa and S-gly – Delta. Comparing the two ligands, what was evidenced was a better affinity of the S-Gly-Omicron/GO-E interaction with Gibbs free energy = - 172.2510 KJ/mol, compared to the better affinity of carbon nanotubes, S-gly/zig-zag with ΔG = -112.73 KJ/mol. The GOs present the eight proposed ligands that tend to bind to the active site of the macrostructures. It is concluded that carbon nanotubes and graphene oxides have a high probability of application in SAR-CoV-2 inhibitor products, through the development of materials that are produced for the manufacture of PPE, Sprays and waterproofing solutions in general.

  • MACIEL DA COSTA FURTADO
  • NUMERICAL AND EXPERIMENTAL STUDY ON THE DRYING IN WAGONS AND PILE

  • Orientador : ANDRE LUIZ AMARANTE MESQUITA
  • Data: 26/05/2023
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  • Dust emissions resulting from handling and transporting particulate materials are a problem in the mining industry. These emissions are more accentuated when the materials are not very humid because the reduced humidity makes the particles lighter and more susceptible to dispersion. Faced with these issues, this study proposes a methodology for the theoretical and experimental study of the drying process that occurs when iron ore fines are transported in wagons or stored in piles in the open. The objective is to clarify the effect of surface moisture in the process of dragging wind iron ores on moist surfaces, such as those found when transporting iron ore in open wagons and in ore pile storage yards. In this study, wind tunnel tests were carried out using a wagon model with fine iron ore and an iron ore pile model. A fixed bed drying study at low velocity is also presented using a wind tunnel dryer. A numerical CFD model was developed, and the results agreed well with the experimental results. The numerical model allowed the evaluation of the drying behavior for different values of air flow velocity and the prediction of the thermal conditions that influence the drying process.

  • PEDRO PAULO GUIMARAES RIBEIRO
  • OPERATIONAL FEASIBILITY OF EMPLOYING THE HW-GMAW PROCESS
    IN STEEL

  • Orientador : EDUARDO DE MAGALHAES BRAGA
  • Data: 19/05/2023
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  • The objective of this study was to investigate the operational viability of the HWGMAW
    variant of the GMAW process in steels welding compared to the CW-GMAW
    and GMAW processes. The study was conducted in two phases and the welds were made
    by simple deposition. In the first phase, an ASTM A-131 grade A rating steel was used,
    varying the additional wire feed rate by 40%, 80% and 120% for CW and HW and current
    at 40A and 80A. Phase, an AISI 1020 classification steel, varying the additional wire rate
    by 20% and 100% HW and the current in 70A. Variance analysis (ANOVA) considered
    that the results were affected by current and power feed wire (1st phase) and the polarity
    and feed rate of wire and torch displacement orientation (2nd phase). The results of the
    1st phase showed a reduction in penetration and dilution with the CW-GMAW process
    in relation to GMAW, however there was a recovery of penetration with HW-GMAW. In
    the 2nd phase, the capture of high-speed image in the study of electric arc dynamics
    suggest that the arc instability when modifying the direction of welding (pulling and
    pushing) and that the polarity of HW was responsible for attracting or repelling the arc
    and, along with the feed rate, it can change cord geometry at a depth of penetration by
    45% and dilution up to 25% compared to GMAW when the feed rate was 100%.

  • ADRY KLEBER FERREIRA DE LIMA
  •  

    PERFORMANCE ASSESSMENT OF A DIFFUSER-AUGMENTED HYDRO TURBINE DESIGNED FOR HARNESSING THE REMAINING ENERGY DOWNSTREAM OF TUCURUÍ DAM

  • Orientador : JERSON ROGERIO PINHEIRO VAZ
  • Data: 15/05/2023
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  •  

    Harnessing the remaining energy downstream of dams has recently attained great
    attention as the kinetic energy transported by the water current is indeed considerable.
    This work develops a study on the performance of a horizontal-axis hydro turbine under
    diffuser effect, in order to quantify the energy gain by comparing both turbines with and
    without diffuser. A 3-bladed hydro turbine with 10 m diameter shrouded by a flanged
    conical diffuser is employed. A numerical modeling using computational fluid dynamics
    is carried out based on the Reynolds Averaged Navier-Stokes formulation, using the K-
    ω SST (Shear Stress Transport) turbulence model. The results yield good agreement with
    experimental and theorical data available in literature.

  • CAIO CAMPOS FERREIRA
  • STUDY OF THE CATALYTIC UPGRADING PROCESS OF RESIDUAL FAT PYROLYSIS VAPORS IN A FIXED-BED REACTOR WITH CHEMICALLY ACTIVATED RED MUD CATALYST

  • Orientador : NELIO TEIXEIRA MACHADO
  • Data: 28/04/2023
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  • This work investigated the effect of catalyst content and reaction time by catalytic upgrading from pyrolysis vapors of residual fat at 450 °C and 1.0 atmosphere, on the yields of reaction products, physicochemical properties (density, kinematic viscosity, refractive index, and acid value) and chemical composition of organic liquid products (OLP), over a catalyst fixed bed reactor, in semi pilot scale. Pellets of red mud chemically activated with 1.0 M HCl were used as catalysts, with contents of 5, 7.5 and 10% (m/m.) of the catalyst/biomass ratio (C/F). The thermal catalytic cracking of residual fat show OLP yields from 54.4 to 84.88 (wt.%), aqueous phase yields between 2.21 and 2.80 (wt.%), solid phase yields (coke) between 1.30 and 8.60 (wt.%), and gas yields from 11.61 to 34.22 (wt.%), and 79.42% (wt.%.) for thermal cracking bio-oil . The yields of OLP increases with catalyst content while those of aqueous, gaseous and solid phase decreases. For all experiments, the density, kinematic viscosity, and acid value of OLP decreases with reaction time. The GC-MS of liquid reaction products identified the presence of hydrocarbons and oxygenates. In addition, the hydrocarbon content in OLP increases with reaction time, while those of oxygenates decrease, reaching concentrations of hydrocarbons up to 95.35% (area.). The best results for the physicochemical properties and the maximum hydrocarbon content in OLP were obtained at 450 °C and 1.0 atmosphere, using a catalyst fixed bed reactor, with 5.0% (wt.) red mud pellets activated with 1.0 M HCl as catalyst. The compositions of the distilled fractions of thermal and catalytic cracking presented average yields between 12-22% by mass, 13-19% by weight and 35-47% by mass of light, medium and heavy distillates, respectively.

  • TIAGO TERIBELE
  • STRUTURAL EVOLUTION OF HYDROCHAR AND KINETICS OF CORN STOVER DEGRADATION BY HYDROTHERMAL PROCESSING WITH HOT COMPRESSED H2O

  • Orientador : NELIO TEIXEIRA MACHADO
  • Data: 24/04/2023
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  • In this work, the effect of reaction time and biomass-to-H2O ratio on the structural evolution of hydrochar and kinetic of by hydrothermal processing of corn Stover with hot compressed H2O, have been systematically investigated. The experiments were carried out at 250 °C, heating rate of 2.0 °C/min, biomass-to-H2O ratio of 1:10, and reaction times of 60, 120, and 240 minutes, and at 250 °C, 240 minutes, heating rate of 2.0 °C/min, and biomass-to-H2O water ratio of 1:10, 1:15, and 1:20, using a pilot scale stirred tank reactor of 5 gallon. The characterization of solid phase products performed by thermo-gravimetric analysis, scanning electron microscope, energy dispersive X-ray spectroscopy, X-ray 7 diffraction, and elemental analysis (C, N, H, S). The physical-chemistry properties of solid phase analyzed in terms of dry matter (DM), total organic content (TOC), and ash. The yields of solid and gas phases decrease linearly with decreasing biomass-to-H2O ratio, while that of liquid phases increases linearly. For constant biomass-to-H2O ratio, the yields of solid, liquid, and gaseous reaction products varied between 52.97 and 35.82% (wt.), 44.84 and 54.59% (wt.), and 2.19 and 9.58% (wt.), respectively. The yield of solids decreases expo-nentially by decreasing the reaction time, while the yields of liquid and gas phases increase exponentially. For constant biomass-to-H2O ratio, TG/DTG curves shows that reaction time of 60 minutes was not enough to carbonize corn Stover. For constant reaction time, TG/DTG curves shows that increasing the H2O-to-biomass ratio worse the carbonization of corn Stover. For constant biomass-to-H2O ratio, the SEM images show the main morphological structure of the corn Stover remains practically unchanged, while for constant reaction time, SEM images show that plant microstructure retains part of its original morphology, demonstrating that a decrease on biomass-to-H2O ratio worse the carbonization of corn Stover. For constant biomass-to-H2O ratio, the EDX analysis shows that the carbon content in hydrochar increases with reaction time, while for constant reaction time, the carbon content decreases with increasing biomass-to-H2O ratio. The kinetic of corn Stover degradation was correlated with a pseudo-first order exponential model, exhibiting a root-mean-square error (r2) of 1.000, demonstrating that degradation kinetics of corn Stover with hot compressed H2O, expressed as hydrochar formation, is well described by an exponential decay kinetics.

  • AUGUSTO FERNANDO DE FREITAS COSTA
  • STUDY OF THE PROCESS OF CATALYTIC UPGRADING OF VAPORS FROM THE PYROLYSIS OF PLASTIC WASTE FROM COMPUTER EQUIPMENT IN CATALYTIC REACTOR WITH ACTIVATED CARBON IMPREGNATED WITH NaOH

  • Data: 03/04/2023
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  • This study investigated thermal cracking and catalytic upgrading of plastic waste from computer equipment on a semi-batch reactor coupled to a heated catalyst fixed bed (2-stage vapor cracking). The catalyst used was a Si–Al ash obtained from commercial activated carbon pellets treated with concentrated NaOH solution and calcination. The purpose of the study was to characterize the waste stream through its thermogravimetry analysis and pyrolysis products, study the effect of temperature (350 - 500 °C) and catalyst quantity (0.0 - 7.5 wt%) on yields of reaction products, physical chemical properties, and chemical composition of organic liquid product in order to understand and evaluate production of fuels and chemical feedstock by recycling of plastic waste from computer equipment through catalytic upgrading. Time-fractioned samples were taken in determined reaction times (15 min, 30 min, 45 min, and 60 min) to study the evolution of cracking reactions during experiment runs through changes to chemical composition (GC-MS). A comparison with other previous work was also presented to show similarities between different feedstocks using the same thermal unit. The results indicate composition of brominated acrylonitrile-butadiene-styrene (ABS), polycarbonate (PC), and high impact polystyrene (HIPS) for the plastic waste from computer equipment. The temperature of 350 °C produced better results when considering acid value but presented lower liquid phase yields (38%) and high gas phase yields (42%). Catalytic upgrading experiments revealed the increased presence of polycyclic aromatic hydrocarbons (PAH) with an increase in viscosity of organic liquid product, increase in char yield (from 11% to 24%), and decrease in gas yields (15% to 5%). Chemical composition showed presence of aromatic hydrocarbons such as styrene, methyl-styrene, and diphenyl-propane and nitrogenated compounds such as benzenebutane-nitrile, phenolic compounds, PAHs, and brominated compounds. Plastic waste from computer equipment pyrolysis is a challenging subject due to contaminant presence and varying composition, and chemical composition evaluation according to reaction time provides interesting insights into the evolution of semi-batch pyrolysis/catalytic upgrading experiments. Standardization and reproducibility of the tool should be conducted to continue the evaluation of pyrolysis and catalytic upgrading of a wide range of feedstocks.

  • ESLEANE VILELA VASCONCELOS
  •  

    BIOCOMPOSITE OF PLA, BIOGLASS AND CARBON NANOTUBE BY 3D PRINTING FOR BONE REGENERATION
  • Data: 31/03/2023
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  • Bone involvement promoted by aging and accidents has aroused interest in biomaterials and technologies for bone regeneration purposes. Thus, 3D printing technology gained prominence in the production of scaffolds due to its versatility in the production of complex geometries with interconnected pores. In this work, scaffolds composed of poly (lactic acid) (PLA), bioglass (BV) and carbon nanotubes (NTC) were produced by 3D printing, using hexagonal geometry, similar to honeycomb, interleaved. Poly (lactic acid) is a biopolymer already used in biomaterials, while bioglass has proven to be an excellent strategy for use in bone regeneration due to its excellent properties of biocompatibility, bioactivity and osteointegration, however they have low mechanical resistance and carbon nanotubes have shown excellent mechanical reinforcement in composite biomaterials. Thus, the main objective of this study was to produce a biocomposite of PLA, bioglass and carbon nanotubes by 3D printing and to study its chemical structure, crystallineity and morphology, using fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction and scanning electron microscope. The thermal stability of the composite was evaluated by thermogravimetry, mechanical properties by compression tests and cell viability was determined by the Alamar Blue test. The bioglass was synthesized by sol-gel method presenting bioactive phases of silicate. The scaffolds were produced by 3D printing with hexagonal structures in honeycomb in PLA, PLA/BV and PLA/NTC that were impregnated with bioglass on its surface. The results of the scaffolds demonstrated interconnected and
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    well-defined pores, ranging from 130 μm to 800 μm. Raman spectroscopy confirmed the interaction of BV in the polymer matrix through new peaks in the spectrum between 1400 and 2600 cm-1 and the presence of the D, G and 2D bands of NTC. In the compression assay, PLA scaffolds with 2 mm diameter showed higher compression stress of 14.88 ± 2.35 MPa, while PLA/NTC higher modulus of apparent compression, 0.58 ± 0.36 GPa. In cell viability, statistical tests showed that there was no significant difference between scaffolds with 2 and 4 mm diameter. The results reveal promising results for the use of 3D printed composites in bone repair in vertebral, ribs, skull and articular bones, however, application in implants remains limited in relation to osteogenic integration.

  • EMERSON RODRIGUES PRAZERES
  • DEVELOPMENT OF NANOSTRUCTURED ALUMINUM ALLOYS FOR USE IN ELECTRICAL CABLES
  • Data: 15/03/2023
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  • Aluminum nanocomposites demonstrate the ability to improve mechanical properties, thermal and electrical conductivity. For aluminum, the incorporation of multi-walled carbon nanotubes (MWCNT) using conventional fusion methods is an age-old problem. In this study, aluminum nanocomposites were manufactured by the conventional casting method, using stainless steel powder (304LSS), nanostructured silicon and nickel. The carbon nanotubes were treated with hydroxide peroxide, allowing a fixation with the particles of the metallic powders. The nanostructured compounds were added to the aluminum matrix by means of conventional casting. After obtaining the material as a melt, it went through the machining process to a diameter of 18.5 mm and then through the cold working process until a diameter of 3.0 mm was obtained. The alloys were characterized mechanically through tensile and microhardness tests, electrically through electrical resistance tests and structurally through macrostructure and microstructure analyses. The 304LSS powder added alloying elements, refined the grains and the NTC improved electrical conductor performance, with electrical conductivity gains in the range of 10%. Associates associated with carbon-associated components not linked to chains of protein chains are compounds of carbon, associated with proteins, aggregates, associated with carbon, associated with proteins, associated with significant proteins in the LRT. The alloys with Ni and carbon nanotubes contributed to significant gains in electrical conductivity and LRT, with the alloy with 2% nickel and 0.1% NTC showing gains of approximately 8% in electrical and mechanical properties. Nanostructured alloys were also superior in terms of electrical and mechanical properties than commercial alloys

  • TAIZA NAIANA DA SILVA FERREIRA
  • O USO DE POLÍMEROS TERMOPLÁSTICOS RECICLADOS NA CONSTRUÇÃO DE RESIDÊNCIAS: UMA PROPOSTA DE HABITAÇÃO POPULAR SUSTENTÁVEL.

  • Orientador : CARMEN GILDA BARROSO TAVARES DIAS
  • Data: 09/02/2023
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  • Nas últimas décadas, o desenvolvimento urbano trouxe como consequência a produção desequilibrada de materiais poliméricos como resíduos, resíduos estes que podem ser reaproveitados como matéria-prima de um novo ciclo produtivo. Este trabalho apresenta como proposta a produção de materiais de placas para serem utilizadas como pisos sustentáveis, blocos ecológicos para vedação com manta termo acústica e telhas sustentáveis. Utilizaram-se resíduos de polímeros termoplásticos para a confecção destes elementos construtivos (piso e telha) e compósitos de matriz reciclada carregada com fibra de caroço de açaí (bloco). Os materiais utilizados para o desenvolvimento do compósito foram copos descartáveis de poliestireno (PS), modelados e processados blocos ecológicos de polipropileno (PP) e polietileno de alta densidade (PEAD) reciclada por rotomoldagem a partir de embalagens pós-consumo apropriados ao processo de reciclagem adotado e posteriormente avaliados os resultados físicos e mecânicos. As paredes foram montadas por blocos de encaixe e produto comercial para assentamento e sobreposição. Após as análises, a utilização da rotomoldagem como modelo de reciclagem de materiais descartados no meio ambiente será capaz de gerar destinação adequada e revalorização, proporcionando renda familiar para catadores de aterros sanitários e aumento do ciclo de vida desses materiais, produzindo produto ecológico na construção civil. Para isso, foi realizada uma seleção de descartes plásticos a partir das etapas básicas da reciclagem mecânica e das características físicas e mecânicas dos reciclados formados. Os resultados foram comparados aos obtidos com os reciclados reforçados e aos de literatura.

  • EDWILLSON GONÇALVES DE OLIVEIRA FILHO
  • HYBRID COMPOSITES REINFORCED WITH CURAUÁ AND CARNAÚBA FIBER FABRICS WITH APPLICATIONS IN BALLISTIC ARMOR


  • Data: 31/01/2023
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  • The development of effective ballistic armor systems is essential to ensure human and vehicle protection. These shields are usually made up of different materials, such as fiber-reinforced polymeric composites, which are used when a good weight/ballistic protection ratio is desired. In addition, the search for ecologically correct materials, which associate good mechanical performance with sustainability, has been very frequent nowadays. The present work was directed to the study of the mechanical and ballistic properties presented by composites reinforced with lignocellulosic fibers, intended for armoring applications. An investigation was carried out regarding the characteristics of curaua (Ananas erectifolium) and carnauba (Copernicia prunifera) fibers, examining the average diameter, morphological and chemical analyses. The mechanical characterization of the composites was carried out using curaua and carnauba fibers in continuous and aligned distributions through manual production of polyester-fiber composites with 10, 20 and 30%v/v, through tensile, flexural and Charpy impact. From these results, laminated polyester composites were produced for the first time, using hybrid systems with layers of Aramid-Curaua, Aramid-Carnauba and Curaua-Carnauba fabrics, adopting the molding process by cold pressing. All proposed hybrid composites have 30%v/v of fibers and were produced in non-alternating configuration, being submitted to ballistic impact tests considering the level of protection and residual velocity. The ballistic results showed that the Curaua-Carnauba systems were perforated, unlike the Aramid-Curaua and Aramid-Carnauba systems, which were not pierced, which obtained a level I of ballistic protection. Although the Curaua-Carnauba configuration of polyester composites with fabrics did not meet the ballistic level requirement, a more comprehensive investigation of the residual velocity is necessary. The results are a strong indication of the possible potential of similar hybrid composite solutions.


2022
Descrição
  • ANDERSON ROCHA AMARAL
  • ESTUDO DE VIABILIADE ECONÔMICA DO PROCESSO DE PIRÓLISE E CRAQUEAMENTO TERMO-CATALÍTICO EM ESCALA PILOTO UTILIZANDO-SE MATERIAL LIGNO-CELULÓSICO, LIPÍDICO, DE ÓLEO DE PALMA (Elaeis guineensis, Jacq) E RESÍDUO DA NEUTRALIZAÇÃO DO ÓLEO DE PALMA

  • Data: 27/12/2022
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  • In this work, it is accomplished a tecno-economic assessment of the production of biooil, coke and gas, via thermos-catalytic pyrolysis followed by distillation. The raw materials were: lipid-base material (residual fat/scum from fat retention box of the University Restaurant at the Federal University of Pará - UFPA), lignin-cellulosic material Açaí seed (Euterpe oleracea. Mart), palm oil and neutrilzing sludge palm oil. From the literature is made a review of the physic-chemical analysis of the raw materials, of the bio-oil and of chemical composition of the biofuels produced (biogasoline, bioquerosene, light-diesel and heavy-diesel). Are also presented the bio-oil yields for each experiment of pyrolysis and distillation and compared with the literature. The economic indicators demonstrated feasibility of the all projects, with exception with the use of açaí seeds. The indicators used to analysis the projects were: a) simple payback criterion, b) discounted payback, c) net present value (NPV), d) internal rate of return (IRR), and e) index of profitability (IP). The minimum fuel selling price (MFSP) obtained is this work for the biofuels was of 1.34 US$/L for all projects, with exception to the palm oil, which was 1,59 US$/L. The sensibility analysis demonstrated that the pyrolysis and distillation yields are the most important variables to affect the minimum fuel selling price (MFSP).

  • GABRIELLE DOS ANJOS CURCINO
  • OPPORTUNITY COST (TRADE-OFF) FOR DIFFERENT MAINTENANCE STRATEGIES AND RAILWAY TRACKS IN THE AMAZON

  • Data: 22/12/2022
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  • The emergency maintenance of railway assets in the Brazilian Amazon has generated revenue losses and opportunity costs. The general objective of this study was to identify the importance of opportunity cost in decision-making for corrective and preventive maintenance strategies. The methodology proposed the modeling of the variables referring to the economic and operational data of railway maintenance in the last ten years, by non-parametric Gradient Boosting Regression Tree machine learning, and hybridizing it with the analysis of the opportunity cost for the trade-off decision- making of an ore railroad in the Brazilian Amazon. The results showed that the GBDT was efficient in fitting the training data with r2 equal to one. Similarly, the test data presented satisfactory r2 values, close to one, where the degree of importance of the independent variables in the prediction of the dependent variables was obtained. Pearson's method was used to construct the correlation matrix for each pair of variables. From the generated model, eight forecast groups were created for the year 2022. Then, conflict levels were established, suggested by the economic literature, between the forecast scenarios, where the opportunity cost was identified among the alternatives with the best benefit to maintenance strategies. In this way, the opportunity cost combined with machine learning serves as an instrument to help companies in the search for better maintenance decisions, which contributes to the improvement of rail asset management.

  • LEDA DE AZEVEDO RACANELLI
  • PRODUCTION OF GEOPOLYMER FROM TAILINGS FROM THE WASHING OF AMAZON BAUXITE

  • Data: 12/12/2022
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  • The State of Pará is the largest national producer of bauxite, representing 85% of the Brazilian production of the ore and, because of this large production, it also represents the largest accumulator of tailings from the processing of this ore, which are deposited in lagoons and/or dams. The intense presence of silica-aluminates in this material, such as kaolinite, for example, demonstrates the great potential for the civil construction industry, that is, the possibility of producing geopolymer materials from this waste. Bauxite washing, after calcination, turns into amorphous material, more specifically into metakaolinite, which can be even more potentiated when mixed with other residues as an additional source of Al and Si, which in this case is called kaolin. Flint. This material has already been the subject of other research projects, becoming known and used to obtain geopolymer materials. As the waste from the bauxite wash has a limited amount of kaolinite, calcined kaolin flint was added to increase the metakaolinite content, helping in the geopolymerization reaction process. The raw materials and geopolymer samples underwent characterization and the main analyzes involved were X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Compressive strength tests were also carried out on the geopolymer samples to assess the degree of polymerization since the more polymerized the structure, the greater the strength. With 28 days of curing, the geopolymer paste of the 80_RLBC formulation reached a compressive strength of 36 MPa and, of the 90_RLBC formulation, approximately MPa at 28 days. The best results were obtained with samples activated with 9 mol/l of NaOH in the mixture with sodium silicate. The results obtained through the characterization analyzes of the samples were satisfactory and demonstrated that the waste from the washing of bauxite and calcined kaolin flint, when activated with sodium hydroxide and sodium silicate, are a viable alternative to produce geopolymer materials.

  • HAMILTON PESSOA PICANCO
  • OTIMIZAÇÃO GEOMÉTRICA DE PÁS DE TURBINAS HIDROCINÉTICAS CAVITANTES SOB EFEITO DIFUSOR

  • Data: 22/11/2022
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  • Diffuser technology placed around hydrokinetic rotors may improve the conversion of
    the fluid’s kinetic energy into shaft power. However, rotor blades are susceptible to the
    phenomenon of cavitation, which can impact the overall power efficiency. This paper
    presents the development of a new optimization model applied to hydrokinetic blades
    shrouded by a diffuser. The proposed geometry optimization takes into account the effect of
    cavitation inception on the rotor blades surface. The main contribution of this work to the
    state-of-the-art is the development of an optimization procedure that takes into account
    the effects of diffuser efficiency, ηd, and thrust, CTd. The model uses the Blade Element
    Momentum Theory to seek optimized blade geometry in order to minimize or even avoid the
    occurrence of cavitation. The minimum pressure coefficient is used as a criterion to avoid
    cavitation inception. Also, a Computational Fluid Dynamics investigation was carried out
    to validate the model based on the Reynolds Averaged Navier-Stokes formulation, using
    the κ − ω Shear-Stress Transport turbulence and Rayleigh-Plesset models, to estimate
    cavitation by means of water vapor production. The methodology is applied to the design
    of a 10 m diameter hydrokinetic rotor, rated at 250 kW of output power at a flow velocity
    of 2.5 m/s. An analysis of the proposed model with and without a diffuser is carried out
    to evaluate the changes in the optimized geometry in terms of chord and twist angle
    distribution. It is found that the flow around a diffused-augmented hydrokinetic blade
    doubles the cavitation inception relative to the unshrouded case. Additionally, the proposed
    optimization model can completely remove the cavitation occurrence, making it a good
    alternative for the design of diffuser-augmented hydrokinetic blades free of cavitation.

  • GILTON CARLOS DE ANDRADE FURTADO
  • ENERGY GENERATION FROM RENEWABLE HYBRID SOURCES WITH PUMPED STORAGE

  • Data: 25/10/2022
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  • This work aims to explore the potential of energy generation and storage existing in hydroelectric plants and dams, especially in the case of Tucuruí, in which the transposition system (Locks) and the islands formed in the upper reservoir offer an additional opportunity for the implementation of systems renewable. In the world context, similar systems in the southern countries are researched, in a literature review, with emphasis on the cases of Brazil and Africa. In the case studies presented, for the Locks, the feasibility of implementing a hybrid solar photovoltaic system with pumped storage to meet the energy demand for operation is evaluated, compared with a purely photovoltaic proposal. On the studied island, a system similar to this is proposed to replace the one installed on site. The advantages of using pump as turbines as a means of energy production and storage are analyzed. Both cases studied showed interesting results from a technical and economic point of view, presenting below average paybacks in similar energy systems, reduced initial investments, ease of maintenance, total demand, with the possibility of absorbing photovoltaic fluctuations. The physical structure of the already existing locks and dams is favorable to these systems, which are environmentally responsible and technologically mature, as they offer the hydraulic head, reducing initial costs.

  • DAVI EDSON SALES E SOUZA
  • ENERGY RECOVERY IN WATER DISTRIBUTION NETWORKS USING PUMPS AS TURBINE A VARIABLE SPEED

  • Data: 21/10/2022
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  • Pumps as turbines (PATs) are considered a cost-effective solution for controlling the pressure in water distribution networks (WDNs) as a replacement for pressure control valves (PCVs). Their use requires an accurate understanding of the various hydraulic conditions during operation in an WDN. This study presents a methodology that details pressure regulation in a municipal network using PATs with velocity control. The WDN sectorization steps are described using EPANET 2.0 software. The selection and associated operation outside of pump design point are presented. Machines are simulated at constant and variable speeds replacing PCVs over 18h of operation. Valve replacement criteria and economic benefits were also estimated. A network was divided into 6 sectors with 14 PCVs, which were replaced by PATs. The selection was quick and based on a good validation of the proposed model. At constant speed, the pump cannot properly regulate the pressure. At variable speed, the PAT 3.3 maintains the best efficiencies (0.62 to 0.64) and power (3.44 kW) when flow rates are high and rotation speeds are low (2,400 rpm and 3,000 rpm). Thus, the outlet pressure values required by the regulation of the PCVs and throughout the network are maintained by the PAT. With the 14 machines operating, the system can recover 270,192.19 kWh/year, with an estimated payback period of 3.75 years, considering a 12-year criteria for a Brazilian utility. Variable speed pumps can regulate the pressure in the WDN like a PCV, recovering a greater amount of energy.

  • LUCAS PINTO BERNAR
  • This work investigated influence of reaction time and catalyst-to-residual fat ratio by catalytic upgrading from pyrolysis vapors of residual fat at 400 °C and 1.0 atmosphere, on the yields of reaction products, physicochemical properties (density, kinematic viscosity, and acid value) and chemical composition of bio-oils, over a catalyst fixed bed reactor of activated carbon pellets impregnated with 10.0 M NaOH, in semi pilot scale. The experiments were carried out at 400 °C and 1.0 atmosphere, using a process schema consisting of a thermal cracking reactor of 2.0 L coupled to a catalyst fixed bed reactor of 53 mL, without catalyst and using 5.0, 7.5, and 10.0% (wt.) activated carbon pellets impregnated with 10.0 M NaOH, in batch mode. Results show yields of bio-oil decreasing with increasing catalyst-to-feed ratio. The GC-MS of liquid reaction products identified the presence of hydrocarbons (alkanes, alkenes, ring-containing alkanes, ring-containing alkenes, and aromatics) and oxygenates (carboxylic acids, ketones, esters, alcohols, and aldehydes). Physico-chemical and compositional analysis show that cracking occurred along the carbon chain present in triglycerides and fatty acids initially present, producing gaseous hydrocarbons. Tha activated carbon catalyst was not selective for the liquid bio-oil deoxygenation, but the obtained results are of great value for understanding the catalytic cracking reaction mechanism.

  • Data: 17/08/2022
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  • Residual fat; Activated carbon pellets; Chemical activation; Thermal catalytic cracking; Catalyst bed reactor, Liquid hydrocarbons. 

  • MANOEL RAIMUNDO DOS SANTOS JUNIOR
  • SIMULATION OF THE DEACIDIFICATION PROCESS OF HYDROCARBON MIXTURES, IN COUNTERCURRENT ABSORPTION COLUMNS, USING SUPERCRITICAL CO2 AS SOLVENT IN THE ASPEN HYSYS SIMULATOR

  • Data: 11/08/2022
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  • In this work, the deacidification of organic liquid products (OLP) obtained by thermal catalytic cracking of palm oil at 450 C, 1.0 atmosphere, with 10% (wt.) Na2CO3 as catalyst, in multistage countercurrent absorber columns using supercritical carbon dioxide (SC-CO2) as solvent, with Aspen HYSYS® process simulator was systematically investigated. In a previous study, the thermodynamic database and the modeling of equations of state necessary to simulate the deacidification of OLP were presented [Molecules 2021, 26, 4382. https://doi.org/10.3390/molecules26144382 ]. This work addresses a new flowsheet, consisting of 03 absorber columns, 10 expansions valves, 10 flash drums, 08 heat exchanges, 01 high pressure pump, and 02 make-up of CO2, aiming to improve the deacidification of OLP. The simulation was performed at 333 K, 140 bar, and (S/F) = 17; 350 K, 140 bar, and (S/F) = 38; 333 K, 140 bar, and (S/F) = 25. The simulation shows that 81.49% of OLP could be recovered and the concentrations of hydrocarbons in the extracts of absorber-01 and absorber-02 were 96.95% and 92.78% (wt.) in solvent-free basis, while the bottom stream of absorber-03 was enriched in
    oxygenates compounds with concentrations up to 32.66% (wt.) in solvent-free basis, showing that SC-CO2 was able to deacidify liquid organic products, obtaining fractions with lower olefin content. The best deacidifying conditions was obtained at 333 K, 140 bar, and (S/F) = 17.

  • MAURICIO MAIA RIBEIRO
  • STUDY OF THE INCORPORATION OF INDUSTRIAL WASTE, RED MUD AND KAOLIN, IN THE PROPERTIES OF POLYESTER MATRIX COMPOSITES REINFORCED WITH JUTE AND MALLOW FIBERS

  • Data: 18/07/2022
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  • A região amazônica do Brasil é um grande produtor de bauxita e caulim, sendo o estado do Pará responsável por uma grande quota nacional da produção destes materiais. O processamento destas matérias-primas gera quantidades consideráveis de resíduos que são depois armazenados em tanques de sedimentação o que podem causar sérios danos ambientais, por conseguinte, é muito importante explorar métodos razoáveis de utilização da lama vermelha e do resíduo de caulim, e assim reduzir os seus volumes dos aterros. Muitos estudos recentes têm sido realizados e apresentados várias formas de utilização abrangente destes resíduos. Os compósitos reforçados com fibras naturais, com inserção destes resíduos industriais, têm recebido nas últimas décadas uma atenção crescente, pois boas propriedades mecânicas específicas podem ser alcançadas e os resíduos industriais podem ser reduzidos e utilizados numa forma útil. Neste trabalho, foram fabricados materiais compósitos de matriz poliéster reforçados por fibras de juta e malva na configuração continuas e alinhadas a 0° e a 90° na direção de carregamento, e materiais compósitos com inserção de resíduos industriais. A matriz poliéster utilizada foi a ortofitálica pré-acelerada e curada a temperatura ambiente com peróxido de metil-etil-cetona 1,0% em massa. As fibras de juta e malva foram cortadas manualmente no comprimento de 300 mm e dispostas manualmente de forma contínua e alinhadas na direção de carregamento e sem tratamento superficial. Os compósitos com fibras foram produzidos por laminação manual assistido a vácuo / ensacamento a vácuo. As proporções da fração de volumétrica das fibras variaram em 5, 15 e 25%. Os compósitos com resíduos de caulim e lama vermelha foram confeccionados pelo processo manual na forma de silicone. Variaram-se as proporções das frações mássicas dos resíduos em 5, 10, 15, 20, 25 e 30 %. Os resíduos foram caracterizados quanto ao aspecto físico, morfológico e químico e as fibras quanto ao aspecto físico e mecânico e os valores experimentais são semelhantes aos apresentados em pesquisas anteriores. Assim como os compósitso fabricados tiveram suas massas específicas determinadas o que resultou no aumento no valor médio da massa especifica dos compósistos com inserção de resíduos de lama vermelha e caulim. No caso dos compósistos reforçados com fibras, de juta e malva, apresentaram uma redução no valor médio quando comparado com a matriz. As propriedades de tração e cisalhamento foram observadas para os compósitos com resíduos industriais, lama vermelha e caulim. O compósito 5RC exibiu valor de resistência a tração mais próximo a matriz, assim como para 5RLV, 10RLV e 15 RLV que exibiram mesmo comportamento. Para a resistência ao cisalhamento os compósitos 10RLV e 15 RLV foram mais próximo a matriz. Assim como os compósitos reforçados com fibras de juta 0° apresentaram a maior resistência a tração foram 0J5, 0J15 e 0J25, excedendo em 2%, 150% e 166% a resistência à tração do poliéster. Para os compósitos reforçados com fibras de malva 0º apresentaram a maior resistência a tração foram 0M15 e 0M25, excedendo em 67% e 96% a resistência à tração do poliéster. Para resistência ao cisalhamento os compósitos reforçados com fibras de juta (0J15 e 0J25) e malva (0M15 e 0M25) excederam a matriz em 201%, 206%, 71% e 144%, respectivamente. A resistência a tração dos compósitos trifásicos (0JRLV, 0JRC, 0MRLV e 0MRC) excederam a matriz em 129%, 100%,54% e 21%, respectivamente. Para resistência ao cisalhamento excederam em 49%, 47%, 63% e 52% a matriz. Os compósitos com fibras alinhadas a 0 apresentaram comportamento mecânico satisfatório para aplicação em materiais compósitos apresentando características de reforço.

  • JESSE LUIS PADILHA
  • Feasibility of generating energy from urban solid waste in small municipalities in the state of Pará

  • Data: 01/07/2022
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  • The most common urban solid waste disposal in Brazil is the landfill. Additionally, there are
    still inadequate disposal units (dumps), but there are technological alternatives for this disposal
    and some projects are already installed in Brazil. The economic analysis is therefore
    fundamental to find the best technological option, transforming an environmental problem into
    a viable solution. This work aims to analyze the financial viability of the combination of
    consolidated destinations for the management of Municipal Solid Waste (MSW) (technological
    routes), that use Waste-to-Energy (WTE), considering small cities with populations from
    30,000 to 250,000 residents and later apply this analysis considering the grouping of
    municipalities in Pará, suitable according to the regional plan for solid waste in the state of Pará.
    A structured algorithm was used with a focus on estimating revenue from the minimum value
    of rate payers' contributions (RPC) to make these routes viable for most cities considered in the
    project. Economic indicators used include: Net Present Value (NPV), Internal Rate of Return
    (IRR), Discounted Payback Period (DPP), and Leveled Cost of Electricity (LCOE). A
    sensitivity analysis of the two best routes was performed (depending on lower RPC values)
    based on NPV. The results tend to confirm solutions that can be approved not only by the
    government, but also by the business sector. The best outcomes are the routes with landfill and
    landfill gas, and with recycling and anaerobic digestion, considering the sale of digestate and
    landfill. These presented the best financial values, with discounted payback periods of 15 and
    20 years, maximum RPC of US$0.04 and US$0.33, per inhabitant/month, respectively, with an
    IRR of 11.61%, for both. The sensitivity analysis indicated a greater influence on the investment
    costs of landfill gas for the first route and for the second route, the urban collection and cleaning
    services and the estimated average percentage of the population's half-minimum-wage income
    expenditure was on average a little above 3%.

  • SHEILA BARBOSA PARANHOS
  • METHODS OF OBTAINING AND CHARACTERIZATION OF CHITOSAN AND COPAÍBA BIOMEMBRANE FOR POTENTIAL USE IN WOUNDS

  • Data: 14/06/2022
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  • Health professionals deal directly with several complex situations in the care of sick people. Among these, there are skin wounds that can harm the patient's clinical condition, in addition to costly treatment for healing. Skin wounds require dressings to protect against pathogenic microorganisms and to accelerate the healing process. With the emergence of biomaterials available for use in wound treatment, chitosan has become an effective choice, easily found in a natural and renewable form with healing potential. The chitosan membrane presents ideal conditions in the treatment of wounds, such as absorption, protection, biocompatibility and antimicrobial potential. To increase its healing effects, natural oils have been incorporated into the polymer matrix, such as copaiba, which has a high anti-inflammatory action. In this context, the work aimed to obtain and characterize chitosan membranes by emulsion and nanoemulsion of copaiba oil to treat skin wounds. The chitosan membranes with oil addition by emulsion and nanoemulsion were synthesized by the solvent evaporation technique. They were evaluated by macroscopic analysis and characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, differential scanning calorimetry, swelling percentage, humidity, contact angle. An in vitro assay of antibacterial activity against the bacterium S.aureus was carried out. The membranes had an apparently thin appearance, little malleability, relative opacity, continuous and good handling. He observed more porosity on the surfaces of membranes synthesized by nanoemulsion of copaiba oil, in addition to a more amorphous behavior. He noticed a better interaction between chitosan and oil constituents when the oil synthesis was prepared by nanoemulsion, resulting in improved stability of the material produced. The swelling percentages were higher in the MQCoN-0.1 (214±3.22%) compositions when immersed in water and the MQCoN-5.0 composition (220±6.83%) in the PBS solution. The wetter behavior was significant in membranes composed of 0.1% (0.80±1.37%) and 0.5% (3.00 ±0.79%) copaiba oil nanoemulsions. There was no great influence on the contact angle between syntheses and compositions. The chitosan membrane with 1.0% (v/v) of emulsified oil and the chitosan membrane with 0.5% (v/v) of nanoemulsified oil were the most hydrophilic membranes. All membranes were able to inhibit bacterial growth, except the chitosan membrane with 1.0%(v/v) oil emulsion. Materials obtained by nanoemulsion have ideal attributes for application in the use of skin wounds.

  • DEBORA DIAS COSTA MOREIRA
  • STUDY INFLUENCE OF PARTICLE SIZE DISTRIBUTION OF THE IRON ORE FINES TO LIQUEFACTION FOR THE MARINE TRANSPORTATION

  • Data: 06/05/2022
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  • In recent decades, many incidents with bulk carriers have occurred due to the liquefaction of solid bulk cargoes, with iron ore being responsible for the largest volume of solid cargo business in the world. The liquefaction of solid bulk cargoes in bulk carriers has been one of the main causes of serious accidents, including loss of life and vessels. iron ore fines (IOF) are products prepared from the refining of iron ore and were reclassified, in 2011, by the International Maritime Organization (IMO), as a liquefiable material of the ' A group'. Currently, the transportable moisture limit (TML) is the only parameter used by the IMO to minimize the risk of liquefaction of 'Group A' cargoes for maritime transport. In this thesis, two methodologies were proposed to investigate the liquefaction potential of IOF, the first methodology aimed to classify the liquefaction potential of IOF samples considering the TML and the Coulomb cohesion factor and the second methodology aimed to use the table test of vibration for analysis of the liquefaction potential of the IOF through proposed indicators. The studies were performed with IOF samples prepared with particle sizes from 9.5 mm to 25 μm in different fines contents (particles < 150 μm) and moisture. In the first part of the thesis, the direct shear tests showed that the addition of fines content in the IOF samples provides great influence on the shear strength. It was also observed, through the Proctor/Fagerberg test and the flow table test, that the addition of fines content in the IOF samples produced an increase in TML. These results were used to propose a methodology for classifying the liquefaction potential of IOF. In the second part of the thesis, the modified Proctor/Fagerberg test showed that there is a transition fine content for the TML. Through the experimental methodology proposed for the vibration table test, it was observed that the liquefaction potential of the IOF has a correlation with the migration of moisture to the surface and values of void ratio, degree of saturation and density are equivalent to the methodology of modified Proctor/Fagerberg test compression. It ends with the proposition of the indicators, Ip and ISWC, which are useful parameters to evaluate the potential for liquefaction of IOF in samples with different contents of fines and moisture; for the tested IOF, Ip ≤ 3.63 indicated that there was no liquefaction and ISWC > 0 indicated liquefaction.

  • LINO ALBERTO SOARES RODRIGUES
  • ANALYSIS OF DISTORTIONS AND RESIDUAL STRESSES IN STIFFENED PANELS WELDED WITH FCAW-ROBOTIZED AND CW-FCAW

  • Data: 22/04/2022
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  • Once the influence of welding imperfections in the form of distortions and residual stresses on the resistance of stiffened panels has been proven, monitoring the levels of these imperfections becomes a safety criterion, in view of the uncertainty of the real resistance losses of the panel, without having to measure the magnitudes of these welding imperfections. Thus, this work deals with the measurement of distortion levels and residual stresses by X-ray diffraction and ultrasonic birefringence in stiffened panels. First, the best of three welding sequences were selected using robotic FCAW welding. Sequence 03 showed distortion levels up to 10 times less and a residual stress level closer to neutrality (±100 MPa) compared to sequences 01 and 02. Then, using sequence 03, panels were welded using the CW-FCAW process with 40% cold wire and welding speeds of 100 m/min and 120 m/min. The results showed that the percentage of cold wire with high welding speeds did not reduce distortions, but influenced the level of residual stresses, leading to stresses closer to the neutral line (±100 MPa) on average.

  • EDUARDO GAMA ORTIZ MENEZES
  • EXTRACTION OF OIL FROM TUCUMÃ-DO-PARÁ (Astrocaryum vulgare) USING SUPERCRITICAL CO2 AIMING FOR SCALE-UP

  • Data: 04/04/2022
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  • With the growing worldwide demand for products and wealth generation, there is a need to invest in new sustainable processes and engineering practices for scale expansion. Thus, the objective of this work was to obtain β-carotene-rich tucumã-do-Pará (Astrocaryum vulgare) oil using supercritical CO2 and to verify the adequacy of two new scale-up equations. Therefore, two isotherms and three pressures (40°C, 60°C, 150bar, 250bar, 400bar) were used. In the condition that presented the highest oil and β-carotene extraction yield, a kinetic study was carried out, followed by the application of a new equation based on Buckingham's π theorem. The highest oil extraction yield (31.49±0.04%) was obtained at 60°C and 400bar with a high concentration of oleic acid, and this yield was similar to the value obtained by soxhlet, which was 32.73±0, 59% oil. The application of the Tukey test (p <0.05) shows that there is no significant difference between the extraction yield obtained in the isotherm of 40 °C and 60 °C in the pressure condition of 400bar. The highest concentration of β-carotene (1351.8±0.02 μg/g) was obtained at 40°C and 400bar, and the solvent density was considered the most significant variable with the greatest influence on β-carotene extraction. The kinetic study carried out with the application of a new mathematical proposal based on the correlation between operational variables (solvent flow, feed mass, height and diameter of the extraction bed), mass transfer mechanism and constancy of the inclination angle of the kinetic curves that , for a solvent flow rate of 10.93 g/min, on the larger scale, the diffusive step controlled the mass transfer mechanism..

  • ELISANGELA DA SILVA FERREIRA
  • SYNTHESIS AND CHARACTERIZATION OF CHITOSAN MEMBRANE WITH GREEN BANANA EXTRACT AND ANDIROBA FOR HEALING OF EPITHELIAL INJURIES

  • Data: 21/03/2022
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  • Biomaterials must enable the surrounging healthy cells to grow and replace the matrix that constitutes the material. The application of other bioactives is being widely studied, as well as the incorporation of phytosan into chemical removal films in wound healing by different techniques. This study aimed to synthesize and characterize chitosan membranes, green banana peel extract and andiroba oil for application in epithelial devices. Membranes were made in different compositions and characterization tests were carried out on the synthesizer. Andiroba oil was added in pure form or oil-in-water (O/W) emulsion in the chitosan solution. Higher in chitosan membranes with emulsion O/W, being 978.79 % e 423.64 %, in Nano M6 and Nano M11, respectively, after 24 hours of life in water. The highest percentage of moisture was in M7 (24.9 ± 3.8 %) and the lowest in Nano M7 (13.46 ± 0.8 %). All samples are hydrophilic, with lower values with banana peel extracts from the first decoction, M1 (24.0° ± 1.9°) and Nano M6 (23.7° ± 4.3°). Diffractograms are mostly amorphous material, for the most part. Thermal analysis has greater stability of chitosan membranes synthesized with banana peel extract and addition of andiroba oil. Spectroscopy showed characteristic peaks and bands of sample components and interaction between these components, as well as suggestion or encapsulation of the oil. The material first presented characteristics of absorption of liquids and synthesized, in particular the membranes of banana extraction of the day of decoction interaction and with addition of O/W emulsions, with greater possibility of duration of its healing of composting epithelial deficiencies.

  • LIANNE MARIA MAGALHAES DIAS
  •  

     

    PRODUÇÃO DE ZEÓLITA A PARTIR DE CINZA VOLANTE DE CARVÃO MINERAL PARA ADSORÇÃO DE METAIS EM LIXIVIADO GERADO NO LIXÃO/ATERRO CONTROLADO NA REGIÃO AMAZÔNICA.

  • Data: 28/01/2022
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  • The formation of solid waste has become a great challenge for the environment preservation due to the lifestyle adopted by modern society, which seeks for practicality and immediacy, and by that, new products are released, and waste formation is increased. The decomposition of waste from various sources creates a dark liquid denominated “slurry”, which presents high concentration of organic and inorganic compounds. This study aimed to evaluate the concentrations of Cd, Cu, Cr, Mn, Ni, Pb, and Zn on the ground and percolated liquid produced at the solid waste decomposition site in the metropolitan region of Belém/Pará/Brazil. Fly ashes of mineral coal were used to produce a low-cost zeolitic material, for removing copper, zinc, cadmium, and chrome, which are present at the percolated liquid of the Aurá landfill. The zeolites synthesized by alkaline fusion (ZSH and ZSJ), and without alkaline fusion (ZSD, ZSG, ZSK, ZSO), were characterized by different techniques, such as X-ray fluorescenc espectrometry, X-ray diffraction, and Scanning Electron Microscopy. The treatment adsorption efficiency of using adsorbent zeolitic material demonstrated viability to be used as an adsorvent agent for the adsorption of metals present at the leachate produced by landfills.

  • PATRICIA BITTENCOURT TAVARES DAS NEVES
  • ARTIFICIAL INTELLIGENCE MODEL FOR ESTIMATING DEFORESTATION CONSIDERING THE ROAD TRANSPORT NETWORK IN THE STATE OF PARÁ

  • Data: 10/01/2022
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  • Since the decade of 1950 the Amazonian and Brazilian transportation complex prioritized the model of road transport. Past studies point that the regular roadway system that is integrated to a clandestine roadway complex is strongly related to the Amazon forest deforestation. Thus, in this work we performed a quantitative analysis of the variables related to the process of deforestation of the Amazon forest, a natural resource of great environment and economic significance, and the socioeconomic development of the region in the period between 1988 and 2018. The geographical study area is the State of Pará, located in the Oriental Amazon, the second largest State of Brazil in territorial extension and the most devastated. We used machine learning in the modeling of the quantitative variables related to the transportation infrastructure, social variables and economic variables, e.g., the devastated area. The random forest model presented the best performance with the generated function (using least squares method). It was estimated the devastated area for the years of 2020, 2030, 2040 and 2050. Sensitivity analysis was used to evaluate the devastated area after the implementation of the roads BR-163 and BR-210 in the north of Pará. The results show that given the current scenario the devastation tends to continue intensively in the next three decades, with a 25.77% increase over the current region albeit with decreasing ten-year rates of forestation loss, and the estimation of the deforested area caused by the implementation of federal roadway networks goes from 4,703.43 km2 to 6,567.48 km2 .

  • PAULO BISI DOS SANTOS JUNIOR
  • Study of the depolimerization process of waste from polymethyl methacrylate resins (PMMA) through pyrolysis

  • Data: 05/01/2022
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  • Polymer materials, due to the diversity of their properties, ease of processing and ability to replace traditional materials, have become indispensable in modern society, although the growing accumulation of plastic waste has become a relevant problem that is difficult to manage. Given this situation, sustainability research has invested in new strategies focused on the processing and transformation of plastic waste where the pyrolysis process presents itself as a promising technology. In this work, the cross-linked PMMA-based dental resins scraps submitted to pyrolysis to recover MMA (Methylmethacrylate). The thermal degradation of cross-linked PMMA-based dental resins scraps analyzed by TG/DTG to guide the operating conditions. The pyrolysis carried out in a reactor of 143L, at 345, 405, and 420°C, 1.0 atm. The reaction liquid products obtained at 345°C, 30, 40, 50, 60, 70, 80, and 110 minutes, physicochemical characterized for density, kinematic viscosity, and refractive index. The chemical composition of reaction liquid products obtained at 354°C, 30, 40, 50, 60, 70, 80, and 110 minutes, at 405°C, 50, 70, and 130 minutes, and at 420°C, 40, 60, 80, 100, 110, and 130 minutes determined by GC-MS. The experiments show that liquid phase yields were 55.50%, 48.73%, and 48.20% (wt.), at 345, 405, and 420°C, respectively, showing a smooth sigmoid behavior, decreasing with increasing process temperature, while that of gas phase were 31.69%, 36.60%, and 40.13% (wt.), respectively, increasing with temperature. The reaction liquid products density, kinematic viscosity, and refractive index obtained at 30, 40, 50, 60, 70, 80, and 110 minutes, varied between 0.9227 and 0.9380 g/mL, 0.566 and 0.588 mm2/s, and 1.401 and 1.414, respectively, showing percentage errors between 0.74 and 2.36%, 7.40 and 10.86%, and 0.00 and 0.92%, respectively, compared to standard values for density, kinematic viscosity, and refractive index of pure MMA (Methylmetaclylate) at 20°C. The GC-MS identified in the reaction liquid products during pyrolysis at 345, 405, and 420°C, 1.0 atm, esters of carboxylic acids, alcohols, ketones, and aromatics, showing concentrations of MMA (Methylmetaclylate) between 83.454 and 98.975% (area.). For all the depolymerization kinetic experiments at 345, 405, and 420°C, 1.0 atm, the concentrations of MMA (Methylmetaclylate) in the liquid phase, between 30 and 80 minutes, reach purities above 98% (area.), decreasing drastically with increasing reaction time after 100 minutes, thus making it possible to depolymerize the crosslinked PMMA-based dental resins scraps by pyrolysis to recover MMA (Methylmethaclylate).

2021
Descrição
  • WILSON LUNA MACHADO ALENCAR
  • Interactions of Co, Cu and Non-metal phthalocyanines with external structures of SARSCoV-2 using docking and molecular dynamics

  • Data: 22/12/2021
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  • The new coronavirus, SARS-CoV-2, caused the COVID-19 pandemic, characterized by a high rate of contamination, propagation capacity and lethality rate. In this work, we approach the use of phthalocyanines as a possible inhibitor of SARS-CoV-2, as they present properties of Cobalt (CoPc), Copper (CuPc) and non-metallic group (NoPc) phthalocyanines as which can interact with SARS-CoV-2 , cut potentially used as adsorption filtration in paints on walls, masks, clothing and air conditioning filters. Molecular modeling techniques through Molecular Docking and Molecular Dynamics were used, where the target was the external structures of the virus, but specifically with the proteases E-pro, M-pro and S-gly. Using the g_MM-GBSA module, and with it the molecular docking studies that the ligands have characteristics capable of adsorbing the structures. Through molecular dynamics we obtain information on the deviation of the root mean square of atomic positions with values between 1 and 2,5. The generalized Born implicit solvation model, Gibbs free energy and solvent accessible surface area approach were used. Among the results obtained through molecular dynamics, it is sought that interactions occur, since phthalocyanines were able to bind to the active residues of macromolecules, demonstrating good interactions; in particular with a CoPc. Molecular couplings and excellent free energy for S-gly active site residues interacted strongly with phthalocyanines with values of -182,443 kJ / mol (CoPc), 158,954 kJ / mol (CuPc), and -129,963 kJ / mol ( NoPc). The possible interactions of phthalocyanines with SARS-CoV-2 may predict some promising candidates for antagonists to the virus, which if confirmed through experimental approaches, could contribute to resolve the global crisis of the COVID-19 pandemic.

  • MARIA ELIZABETH GEMAQUE COSTA
  • Morphological, crystalline and textural characterization of bio-adsorbents produced via hydrothermal processing of corn husk residues with sub-critical H2O: Application in acetic acid adsorption
  • Data: 06/12/2021
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  • This work aims to investigate the influence of temperature on textural, morphological, and crystaline characterization of bio-adsorbents produced by hydrothermal processing of corn Stover with hot compressed H2O. The experiments were carried out at 175, 200, 225, and 250 ºC, 240 minutes, heating rate of 2.0 ºC/min, and biomass/H2O ratio of 1:10, using a pilot scale reactor of 18.927 L. The process performance analyzed in terms of yields of reaction products as a function of temperature. The results showed solid yields ranging from 62.92 to 35.82% (wt.), gas yields ranging between 1.49 and 9.59% (wt.), and reaction liquid products yields ranging from 35.43 to 54.59% (wt.). The solid phase yield decreases with increasing temperature, showing an inflection region between 200 and 225 °C, whereas a drastic change takes place, while that of liquid phase increases, showing also a drastic change between 200 and 225 °C. The yield of gaseous phase increases exponentially with temperature up to approximately 10% (wt.) within the investigated temperature range. The elemental analysis of solid products shows that carbon content increases, while that of oxygen and hydrogen decreases with increasing temperature. The textural, morphological, and mineralogical characterization of solid phase products analyzed by thermo-gravimetric analysis, scanning electron microscope, energy dispersive X-ray spectroscopy, X-ray diffraction and BET. The solid phase product (bio-adsorbent) obtained by hydrothermal processing of corn Stover at 225 and 250 °C, reaction time of 240 minutes, and biomass-to-water ratio of 1:10, were activated chemically with 2.0 M NaOH and 2.0 M HCl solutions in order to investigate the adsorption of acetic acid solutions (1.0, 2.0, 3.0, and 4.0 mg/mL). The adsorption kinetics investigated at 30, 60, 120, 240, 480, and 960 seconds. The adsorption isotherms show that chemically activated hydrochars were able to recover acetic acid from aqueous solutions.

  • ALICE DOS PRAZERES PINHEIRO
  • SYNTHESIS OF ZEOLITIC PRODUCT FROM HARD KAOLIN: PRODUCTION OF ADSORBENT BED APPLIED TO ION ADSORPTION AMMONIUM
  • Data: 05/11/2021
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  • The development of new technologies has enabled and created new ways of using kaolin, besides the already known applications. One of these known uses is the use as starting material for zeolitic synthesis, a type of kaolin with great potential for this purpose is called hard kaolin. Due to the low crystalline structural degree, the hard kaolin is naturally more reactive for zeolitic synthesis. Having this condition available, the study in question aims to resort to this condition and evaluate the possibility of synthesis and reproducibility of the synthesis of zeolite using kaolin in natura, without previous thermal or chemical treatments and consecutive cationic calcium and lithium exchange. The conformation of the synthesized zeolitic product in various formats for subsequent application as an adsorbent product in a fixed bed column, also developed in the study for the adsorption of ammonium ion and subsequent desorption, with the intention of investigating the potential of the conformed product as a slow release fertilizer for agricultural purposes. X-ray diffractometry of the zeolitic product indicated the presence of crystalline peaks of zeolite A, sodalite and anatase. The electronic microscopy images presented a morphology analogous to wool balloons, characteristic of sodalite. The adsorption capacity obtained from the experiments performed in the fixed bed column developed in the study indicated good results with potential optimization of the adsorption system at different concentrations and ions

  • PAULO ROBERTO DE OLIVEIRA BRITO
  • SUPERFICIAL REINFORCEMENT IN ALUMINUM CAST BY CARBON NANOTUBES THROUGH SOLUBILIZATION TREATMENT

  • Data: 14/10/2021
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  • Carbon nanotubes (CNTs) are noteworthy, as they reinforce the metallic matrix, due to mechanical properties, such as the ~ 1.0 TPa Young module. To improve the maintenance of the commercially pure aluminum surface, multi-walled carbon nanotubes (MWCNTs) were incorporated into the aluminum surface with heat treatment by solid solubilization, in order to improve the surface properties of aluminum. The aluminum samples were subjected to chemically attacked with the Keller reagent, for a period of 30, 60 and 120 seconds, and soon after the roughness assessment was carried out, and then they were placed in a container containing NTCs, being subjected to a 640°C for one hour. Afterwards, the morphology was evaluated in the scanning electron microscope, where an aggregate of NTCs was observed, the DRX was performed to evaluate the addition of the NTCs in the matrix, and the Raman Spectrum that evaluated the charge transfer to the matrix. Microhardness was performed to evaluate the result of the incorporation of the NTCs in the matrix. The results obtained show that the incorporation of CNTs in the aluminum matrix increases the hardness in approximately 20% of the surface, in comparison with the control sample. The process of incorporating CNTs into the aluminum matrix by solubilization is a promising, simple and inexpensive alternative to improve the durability of the aluminum surface.

  • LIDIANE DINIZ DO NASCIMENTO
  • Lippia thymoides Mart. & Schauer ESSENTIAL OIL: OBTAINING, CHEMICAL CHARACTERIZATION AND MICROENCAPSULATION

  • Data: 27/08/2021
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  • The species Lippia thymoides occurs in Brazil and is widely described for its medicinal properties, however, there are still few studies describing applications of its essential oil. This study presents a review of the microencapsulation of essential oils and the importance of these natural products and their applications. Besides, the leaves of L. thymoides were subjected to drying in an oven at 40, 50 and 60°C and it was evaluated the drying kinetics and the influence of the drying process on the chemical composition, yield, and antioxidant profile of the essential oils. The chemical composition was performed using the GC/MS and GC-FID. After obtaining and characterization, the essential oil of L. thymoides was microencapsulated by the spray drying process. The biopolymer arabic gum was used as encapsulating material, in a ratio of 1:6 to the essential oil content. During the process, the inlet temperature was 140°C, the feeding rate was equal to 0.5 L/h and the atomization pressure was 4.5 bar. After the microencapsulation, it was carried out the physical-chemical and flow characterization. Also, the surface and chemical composition of the microcapsules were analyzed. According to the results obtained in the drying study, the Midilli model was the most appropriate to describe the drying kinetics and thymol was the main compound in all conditions analyzed, highlighting that the highest percentages were identified in the essential oil extracted from the fresh leaves (62.78 ± 0.63%). On average, essential oils showed an inhibition of the DPPH radical equivalent to 73.10 ± 12.08% and the fresh leaves showed the highest percentage of inhibition (89.97 ± 0.31%). The microencapsulation process resulted in a powder yield in the range of 51.44 ± 0.68% and the microcapsules presented a safe moisture content (3.92 ± 0.64%), good solubility in water (71.26 ± 6.26%), and encapsulation efficiency equal to 87.20 ± 3.00%. The thymol content in the microcapsules increased 2x concerning the percentage quantified in the oil before encapsulation and, therefore, based on the properties analyzed, the microencapsulation was efficient and capable of providing microcapsules rich in thymol, a constituent of high commercial interest.

  • HERICA DANIELE COSTA ARAUJO
  • INTERACTIONS OF ACTIVATED CARBON, DRUGS AND LIBIDIBIA FERREA AGAINST SARS-COV-2 VIRUS

  • Data: 25/08/2021
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  • The high rates of infection and mortality from Severe Acute Respiratory Syndrome (SARS-CoV-2) or COVID-19 infection has caused severe socio-economic impacts worldwide. Transmission ba-sically occurs through contact with bodily fluids. In the airways, by spraying droplets and/or aero-sols suspended in the environment and/or deposited on surfaces. The effectiveness of using effec-tive masks to contain contagion is a necessity. The present work evaluated the adsorption capacity of filters containing activated carbon and modified activated carbon during nanofiltration in masks with greater efficiency. The possible interactions between Spike (S) and membrane (M) proteins with activated carbon oxygen non-modified and activated carbon oxygen modified were evaluated by docking and molecular dynamics. Autodock Vina 4.2.6 and AMBER 16 software were used in the simulations. Results of the formed ligand-receptor complexes had the affinity energy, the root-mean-square deviation (RMSD) and the Gibbs free energy of binding evaluated. Activated carbon oxygen modified showed greater spontaneity in protein interactions. And, another front to combat the coronavirus was addressed in this work: the treatment of the infected, as evaluations of the inhibitory action of the active principles of retroviral drugs known in the literature, as well as new compounds from the Brazilian Amazon flora were docked with proteins S, M and envelope (E). Three drugs (Colchicine, Nafamostat and Selinexor) and three compounds originated from Li-bidibia ferrea or Caesalpinia ferrea (Elagic Acid, Pauferrol A and Sitosterol) interacted as ligands. And, after docking, the most favorable affinity energies of the active sites established between lig-ands and receptors were graphically demonstrated. The docking was carried out through the SwissDock server. The interactions of the ligands Pauferrol A and Colchicine on the proteins con-tained in the viral surface were highlighted.

  • CONCEICAO DE MARIA SALES DA SILVA
  • Hydrothermal carbonization of açaí seeds (Euterpe oleracea, mart) with hot compressed H2O 

  • Data: 13/08/2021
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  • This work aims to investigate systematically the influence of process temperature, biomass-to-water ratio, and production scales (laboratory and pilot) on the chemical composition of aqueous and gaseous phases and mass production of chemical by hydrothermal processing of Açaí (Euterpe Oleraceae, Mart.) seeds. The hydrothermal carbonization carried out at 175, 200, 225, and 250 °C, 2 °C/min, biomass-to-water ratio of 1:10, and at 250 °C, 2 °C/min, and biomass-to-water ratios of 1:10, 1:15, and 1:20, in technical scale, as well as at 200, 225, and 250 °C, 2 °C/min, biomass-to-water ratio of 1:10, in laboratory scale. The elemental composition (C, H, N, S) of solid phase determined to compute the HHV. The chemical composition of aqueous phase determined by GC and HPLC and the volumetric composition of gaseous phase by using an infrared gas analyzer. For the experiments in pilot scale with constant biomass-to-water ratio of 1:10, the yields of solid, liquid, and gaseous phases varied between 53.39 and 37.01% (wt.), 46.61 and 59.19% (wt.), and 0.00 and 3.80% (wt.), respectively. The yield of solids shows a smooth exponential decay with temperature, while that of liquid and gaseous phases a smooth growth. By varying the biomass-to-water ratios, the yields of solid, liquid, and gaseous reaction products varied between 53.39 and 32.09% (wt.), 46.61 and 67.28% (wt.), and 0.00 and 0.634% (wt.), respectively. The yield of solids decreases exponentially with increasing water-to-biomass ratio and that of liquid phase increases in a sigmoid fashion. For constant biomass-to-water ratio, the concentrations of Furfural and HMF decrease drastically with increasing temperature, reaching a minimum at 250 °C, while that of phenols increases. In addition, the concentrations of CH3COOH and total carboxylic acids increase, reaching a maximum at 250 °C. For constant process temperature, the concentrations of aromatics vary smoothly with the temperature. The concentrations of furfural, HMF, and cathecol decrease with temperature, while that of phenols increases. The concentrations of CH3COOH and total carboxylic acids decrease exponentially with temperature. Finally, for the experiments with varying water-to-biomass ratios, the productions of chemicals (furfural, HMF, phenols, cathecol, and acetic acid) in the aqueous phase is highly dependent on the biomass-to-water ratio. For the experiments in laboratory scale with constant biomass-to-water ratio of 1:10, the yields of solid ranged between 55.9 and 51.1% (wt.), showing not only a linear decay with temperature, but also a lower degradation grade. The chemical composition of main organic compounds (furfural, HMF, phenols, cathecol, and acetic acid) dissolved in the aqueous phase in laboratory scale shows the same behavior of those in obtained in pilot scale.

  • CRISTHIAN RICARDO LOAYZA LOAYZA
  • STAINLESS STEEL NANOESTRUCTURED MANUFACTURE VIA ARC WELDING

  • Data: 08/07/2021
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  • Manufacturing methods of nanostructured stainless-steel composites (NSSC) have not yet been developed with industrial applicability. To overcome this shortage, the possibility of incorporating nanoparticles by electric arc welding was investigated, using a tubular rod filled with nanostructured flux composed of multi-walled carbon nanotubes (MWCNT) and 304L stainless steel particles. This flux was manufactured by two different methods: mechanical alloying (MA) and chemical treatment (CT) with hydrogen peroxide. The second showed more promising results using control of kinetic parameters of time and temperature, obtaining a lower degree of amorphous carbon, impurities, and crystalline defects, increasing their crystallinity and interaction of the nanotubes with the metallic
    matrix. MWCNT incorporation decreased the grain size by 64% when compared to the stainless-steel coating, possessing an austenitic matrix with carbide precipitation in the interdendritic spaces and grain boundaries. The microhardness increased 45% and the rate of erosion by vibratory cavitation decreased 64%, in relation to the AISI 304L coating. Additionally, XRD analyses showed a reduction of the γ{200} phase and a growth of γ{111} after the cavitation process. The method of manufacture of the nanocomposites proved to be economically viable and with the possibility of immediate application on a large scale.

  • DARLLAN DO ROSÁRIO PINHEIRO
  • AMAZONIAN STERILE KAOLIN AND KAOLIN WASTE AS SOURCES OF Si AND Al IN OBTAINING SAPO-34: SYNTHESIS, OPTIMIZATION, IMPURITY INFLUENCE AND APPLICATION IN DYE ADSORPTION

  • Data: 27/05/2021
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  • Kaolin waste from kaolin industry sedimentation ponds for paper and sterile kaolin or flint belonging to the same mine, in the Capim region, in northeastern Pará, were used in the synthesis of the SAPO-34 molecular sieve. The precursor materials and those produced were characterized by: DRX, FRX, TG-DSC-DTG, FTIR, ASEBET and MEV. First, the use of R-metakaolin as a precursor was evaluated, varying the SiO2 / Al2O3 ratio in the formulation of the SAPO-34 molecular sieve. The adjustment in the value of this molar ratio showed a positive effect on the formation of the desired zeolite, which showed formation of the CHA structure, in less time and with good thermal stability. In relation to the use of F-metakaolin, the effect of the amount of SDA and crystallization time (nucleation and crystal growth) on the formation of the CHA structure was evaluated and, later, that zeolitic product formed with less amount of SDA was used for a detail evaluation, in which the influence of Fe and Ti ions type impurities was studied. The results revealed a positive effect of the greater amount of SDA in the formation of SAPO-34 (CHA), but in a shorter time and, consequently, contribution in the Si distribution in the structure. When comparing the zeolitic products derived from F-metakaolin and a high purity kaolinitic pattern, the zeolitic product obtained from the kaolinitic sterile showed thermal resistance where the calcined product's DRX pattern maintained the CHA diffractometric profile, but with reduced crystallinity. It was also observed that before calcination, the zeolitic product obtained with F-metakaolin showed a smaller displacement to a 2θ (º) angle, indicating an increase in the interplanar distance with reference to the d101 plane, possibly due to interferences of the present impurities (Fe and ions). Ti), however after the calcination for decomposition of the SDA this displacement was not evidenced, thus indicating interference of the SDA used. That product considered the best, based on crystallochemical parameters, was used in the performance evaluation in methylene blue adsorption, which showed good adsorption capacity. In the evaluation of the adsorption kinetics, the pseudo-second order model (R2 = 0.998) was the one that best fit the experimental data. The optimization of the synthesis using tailings through the planning of Box-Behnken experiment and response surface methodology. It was concluded that the use of Amazon waste and/or flint kaolin is viable for the production of SAPO-34 zeolite (CHA).

  • TIAGO MIRANDA PEREIRA
  • STUDY OF HYDRODYNAMIC BEHAVIOR OF TURBINE FLOWMETERS APPLIED TO LIQUEFIED PETROLEUM GAS THROUGH BLADE ELEMENT THEORY CONSIDERING THE CASCADE EFFECT

  • Data: 28/04/2021
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  • Turbine flowmeters are widely applied in industry to quantify transferred amounts of liquid products, even for commercial purposes, due to its high accuracy and large operational range. The development of engineering computational tools to analyze and improve performance of such meters offers to the engineer the possibility of contribution to society, increasing quality of measurements and minimizing distortions in supply chain potentially harmful to final consumers. Most turbine flowmeters have several blades, becoming the determination of lift and drag coefficients still challenge. This makes cascade effect indeed relevant, without which the performance of the turbine can be overestimated by the Blade Element Theory (BET) analysis. Hence, the present work proposes the application of BET to the analysis of hydrodynamic behavior of turbine flowmeters applied to Liquefied Petroleum Gas (LPG) measurement. The proposed model calculates the cascade effect correction due to the local solidity throughout turbine blades length, in order to accurately predict lift and drag coefficients at each blade section. Operational parameters of the studied equipment are obtained from the proposed computational model and compared to the field performance of an existent measurement system for several conditions within the operational range, revealing satisfactory coherence. For this analysis, computational fluid dynamics (CFD) techniques are employed, through the finite volume method. For validation of the CFD model, computational results are compared to in-situ data acquired during regular operation of the measurement system. Cavitation susceptibility is also evaluated through the CFD model, in order to provide indication of boundary limits inside which operational conditions are maintained within specifications. As a result, the study indicates that turbine flowmeter performance can be predicted by the proposed computational modeling strategy based on the BET analysis and  field results of angular velocity and linearity can be accurately reproduced. 

  • ANA JULIA SOARES DA SILVA BARBOSA
  • EXPERIMENTAL-NUMERICAL MODELING OF THE PRODUCTION OF SEDIMENTS OF SMALL HYDROGRAPHIC BASINS OF AMAZON

  • Data: 22/04/2021
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  • Erosion is a process of direct impact in urban and rural environments. The understanding of this process requires the use of models and techniques of geoprocessing and field, for approximate estimation of the realized one, since it is a phenomenon with many variables to be taken into account. For the present study, two models were used to generate data in a small Amazon basin. The USLE (universal soil loss equation) and also the modified MUSLE version. For both models, the common factors (K, LS, C and P) were determined. For USLE, the calibration occurred for rain erosivity, which is the differential factor of this model. After USLE application with calibrated R factor, the model was applied to the study area with an average soil loss of 1.99 ton. ha-1.year-1, for a period of 21 years. For MUSLE, the differential variables are the hydrological variables (Q and qp) were determined by analyzing the hydrographs observed with the aid of a digital filter. Two methods of calibration and validation have been done for MUSLE. Method 1 calibrated the factors ɑ and b, with sediment production data measured from 62 flood events from 2012 to 2014. The values found for factors ɑ and b were equal to 19.90 and 0.60, respectively. MUSLE was validated with sediment production data measured from 62 flood events in the years 2014 and 2015. The validated MUSLE equation represented in a satisfactory way, in more than 70%, the data of soil loss observed in the hydrographic basin of the Igarapé da Prata. Method 2 calibrated only the value of a, using the solid discharge curve with potential regression for the years 2012 and 2013, which showed R² of 0.70 and 0.68, respectively. The value of ɑ obtained was 17.25, and was applied to MUSLE, keeping the value of b at 0.56, the original value of the model. The validation for the latter method proved to be adequate, with an R² of 0.69. These results validate the empirical models for the region with experimental activities, which corroborates for the production of sediment information in the Amazon region, as a way of maturing and the search for new research, for the understanding of the impacts arising from the transport of soil between areas and in the water environment.

  • CAIO CÉSAR AMORIM DE MELO
  • QUALITY CONTROL OF GIBBSITIC BAUXITES: PREDICTION OF PARAMETERS AvAl2O3 AND RxSiO2 FROM REFLECTION AND TRANSMISSION DIFRATOMETRIC DATA BY USING MULTIVARIATE STATISTICS

  • Data: 16/02/2021
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  • Currently, traditional wet chemistry methods are used for quality control of bauxites. Such methods indirectly quantify the gibbsite and kaolinite content as available alumina (AvAl2O3) and reactive silica (RxSiO2), respectively, and they are very costly and time-consuming. In order to achieve a rapid and reliable method to estimate these parameters, as alternative to current wet chemistry methods, in this work it is evaluated the use of multivariate statistics – Partial Least Square Regression (PLSR) on XRD data of Brazilian bauxites. The X-ray diffractograms were collected in the “reflection” and “transmission” modes, and the data collected by each of these treatments were compared with respect to the quality of the PLSR models. The method was optimized through Principal Component Analysis (PCA) and Factorial Design of Experiments (DOE), from which it was possible to identify outliers and cluster of samples with mineralogical similarities, and obtain optimized parameters for the collection and pre-treatment of diffractograms. Compared to the traditional method, the precision was within the acceptable industrial limits, but with the advantages of being a significantly faster method, easier to implement and perform the analyzes, it requires less space and manpower, besides no chemical reagents are needed. In addition, with the implementation of X-ray diffraction in the laboratory of the bauxite and alumina industry, it is possible to follow the mineralogy of the ore that feeds the Bayer process and, therefore, to x be aware of how variations in the mineralogical composition can impact the process. It is worth noting that such information is still unknown, controlling only the chemical parameters.

  • JULIO CÉSAR NUNES AIRES
  • NARCOTICS, NATURAL GAS, SYNGAS AND HYDROGEN SENSORS USING CARBON NANOTUBES UNDER EXTERNAL ELECTRIC FIELD ACTION

  • Data: 15/02/2021
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  • This work presents an analysis of the molecular dynamics between several illicit drugs: benzoylmethylecgonine, diacetylmorphine, 3,4 methylenedioxymethamphetamine, DDeoxefedrine, lysergic acid diethylamide and, interacting with a section of carbon nanotubes at low initial simulation temperature, corresponding to 10 −3 K, and under a uniform electric field, as a drug detection system. In addition to the analysis of the behavior of natural gas molecules and SYNGAS interacting with a carbon nanotube at an initial simulation temperature of 300K, with all systems being relaxed for 50 ps outside the carbon nanotube, describing each possible arrangement for catch; a constant external electric field was then applied to the systems, longitudinally, along the length of the carbon nanotube, promoting an evanescent effect, capable of trapping them orbiting the carbon nanotube. Simulations for electric field intensities within a range of 10-5 to 10-1 ua were performed to verify the behavior of drugs, while for the molecules that comprise natural gas and syngas, a range of 10-8 to 10-1 ua was adopted. Average orbital radii were estimated, in addition to a number of thermodynamic properties. Our results indicate that the combination of a uniform external electric field and van der Walls interactions in a carbon-derived nanotube is sufficient to create an evanescent field of attractive potential, presenting it as a system for the detection of drug temperatures and rays.

2020
Descrição
  • PAULO D ANGELO COSTA ASSUNCAO
  • VIABILITY STUDY OF GMAW WELDING RESIDUAL STRESSES and WELDING NARROW GAP-CW, DCW-GMAW.

  • Data: 17/12/2020
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  • The welding process (CW-GMAW) proved innovative, as it increases productivity without increasing damage to the material. This work will investigate other benefits that the process (CW-GMAW) can bring, such as narrow bevel welding and DC negative polarity welding, as well as the addition of two cold process wires (DCWGMAW). It will be investigated by acoustic birefringence, the residual stress in joints welded by the GMAW process. The residual stresses will be calculated by the difference in stresses and the stress-decomposed equation in two planes. The fact that the cold wire attracts the electric arc made welding possible in a narrow chamfer prevents erosion of the chamfer sidewall. This mechanism suggests having suppressed the electric arc's scaling in polarity (CC-), consequently improving the arc stability and the weld bead finish. Welding with DCW-GMAW showed better arc stability and less heat affected zone HAZ. Moreover, the calculations made with the different equations showed that although it needs a little more work, the decomposed residual stress calculation allows a more accurate view compared to the calculation made by the differences in stress

  • MARCIA DE FATIMA PANTOJA FERREIRA
  • STUDY OF THE CONSTITUENTS OF PYROLYSIS PRODUCTS for PRODUCTION OF BIOFUELS and CHEMICALS 
  • Data: 21/09/2020
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  • This work aims to use slow pyrolysis in biomass residues (EFB) as an energy potential in the production of biofuels. The raw material was obtained from agribusiness and subjected to washing, drying and crushing. The experiments were carried out in a fixed bed reactor and the central rotational composite design was used to optimize the variables temperature (459, 500, 600, 700, 741 ° C) and nitrogen flow (0,259; 0,3; 0,4; 0,5 and 0,541 L / min), in order to identify the ideal conditions for obtaining bio-oil (BO). From the optimized result, the products were characterized using various techniques (FTIR, CG / MS, CCDAE, NMR, MEV, Karl Fischer, CHNO). Temperature was the most influential parameter in relation to liquid and solid yields, and the combination of variables influenced the yield in gas. There was a higher yield in BO (45,29%) whose composition showed a large amount of fatty acids, alkanes, alkenes and phenolic compounds, the latter with high antioxidant capacity. Biochar showed low yield (27,52%), but good energy capacity, the gas yield was 27,89%. The calorific value of the BO was 24,48 MJ / kg and the biochar was 19,27 MJ / kg. The results of the techniques used, prove the use of EFB as a renewable source in obtaining biofuels.

  • ALESSANDRO JOSÉ GOMES DOS SANTOS
  • COMPOSITE MATERIAL INCORPORATED WITH BAMBOO (BAMBUSA VULGARIS) FIBERS AND SOLID INDUSTRIAL WASTE FOR USE AS A STRUCTURAL COMPONENT FOR CIVIL CONSTRUCTION

  • Data: 12/03/2020
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  • The production of materials that cause less environmental impacts and that have a high sustainability, mainly those that cause vegetable fibers and industrial residues, increases. In this work, unsaturated polyester matrix compounds, bamboo vegetable fiber compounds, industrial waste compounds (red mud, copper and copper syrup) and hybrid compounds with variation of waste and fiber samples were made. The residues were used with 100 mesh granulometry and as fibers in the lengths of 15 mm and 30 mm, randomly arranged within the matrix. These fibers were used in nature and treated with 5% NaOH during the period of 2 (two) hours. The fibers were characterized in terms of their physical, mechanical and morphological properties. The compounds were made by manual process (manual arrangement) in the form of rectangular plates in a metallic mold and pressed. It varies as proportions of the mass fractions of residues in 10% until the saturation within the matrix which was 40%, whereas the mass fraction of fibers was varied from 1% to 3%. For the production of hybrid compounds, the variation occurred up to the maximum saturation level of the matrix. Bamboo fibers were chemically characterized by extractors, lignin and holocellulose analysis. The residues were characterized mineralogically by means of X-Ray Diffraction (XRD). The compounds were physically characterized (apparent porosity, water absorption and apparent specific mass), mechanically (exposure, flexion and impact), flame retardation and morphologically through Scanning Electron Microscopy (SEM) analysis. For physical characterization analyzes, 10 specimens (CP's) were used for each series. In 11 mechanical tests, on the other hand, 10 CPs were manufactured, while flexion and impact tests were 8 CPs for each series. This same amount was used for the flame retardancy tests. After clinical trials, an increase in Apparent Specific Mass was observed with the addition of residues and fibers in the matrix. In the analyzes through the mechanical characterization of the penetration, the best results of resistance limits in the values of 33.05 MPa are obtained for compounds with 3% bamboo fibers treated with 15 mm in length and 33.11 with bamboo fibers 30mm long without treatment. With the incorporation of waste, it reached a value of 40.25 MPa. The hybrid fractions or value reached 41.07 with the addition of 20% kaolin residue / 3% bamboo fibers in the 15 mm components with treatment. Bending tests or results of 150.94 MPa for added fibers with 30mm treated, 140.34 MPa for adding 20% of kaolin residues and hybrids of 137.27 MPa for adding 30% of kaolin residues / 3% bamboo fibers with 30mm treatment. Impact tests with better results of 23.02 kJ / m² for addition of 10% copper residue and 38.56 kJ / m² for addition of 20% copper residue / 3% bamboo fibers with 30 mm in length treated.

  • ROSELY MARIA DOS SANTOS CAVALEIRO
  • NANOFILTRATION OF HORMONES AND HEAVY METALS IN CARBON AND
    BORON NANOTUBES BY MOLECULAR DYNAMICS

  • Data: 27/02/2020
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  • Sewage treatment stations receive various effluents and perform the selective filtering of
    molecules that can, if they persist in the water, contaminate or the environment. Selection
    processes initiated by larger sections down to nanoparticles. Among the molecules called
    emerging contaminants are hormones and heavy metals that impact on graves consequences on
    organisms by endocrine-disrupting action. When surface waters receive effluents with traces of
    contamination and hormones or heavy metals, they will cause diseases in living beings,
    especially in pregnant women and children, as well as interfering in the chains of DNA, also
    affecting the next generations. This study of molecular tests carried out with nanofiltration:
    water with hormones and water with heavy metals filtered through carbon nanotubes and boron
    nitrogen, under the action of 8 (eight) electric fields lasting 100 (hundred) picoseconds. The
    study hormones were: estrone, estradiol, estriol, progesterone, ethinylestradiol, levonorgestrel,
    diethylbestrol, and heavy metal ions: lead, cadmium, iron, zinc, and mercury. Each of the
    hormone molecules and the heavy metal were filtered through two nanotubes, under the same
    boundary conditions. The selected results that allow creating nanofiltration systems that can be
    removed micropollutants using carbon nanotubes or boron nitride activated by the electric fields
    from 10-5 to 10-8 atomic units.

  • LEILIANE DO SOCORRO SODRE DE SOUZA
  • OBTAINING FERMENTABLE SUGARS FROM ANDIROBA PEEL (Carapaguianensis Aubl.): STUDY OF ALKALINE PRETREATMENT AND KINETIC EVALUATION

  • Data: 24/01/2020
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  • In this study, andiroba seed peels were subjected to alkaline pretreatment, to maximize the recovery of reducing sugars, evaluating the best operating performance through the variables, reaction time (20, 60 and 100 min), NaOH concentration (2, 3 and 4 % (m / v)) and temperature (60, 90 and 120 ºC), at a fixed solids concentration of 5% (m/v). BoxBehnken experimental design (15 runs) was used. The pretreated biomass in the 15 experiments was enzymatically hydrolyzed, under identical conditions, solids loading (5%), enzymatic loading (15 FPU / g of biomass) and reaction time (48 hours). Lignocellulosic material was characterized by cellulose analysis (36.96 %), hemicellulose (16.74 %), lignin (36.02 %), extractives (7.49 %), moisture (9.21%), and ashes (1.53 %). The optimization was performed using the response surface methodology approach. The model provided a coefficient of determination (R²) of 0.96 for saccharification and 0.97 for recovered solids. The predicted optimal conditions for the process were: reaction time = 100 min, NaOH concentration = 4% (m / v), temperature = 120ºC, which resulted in a conversion in terms of reducing sugars of 47.89%. Pretreated lignocellulosic material under the best conditions was morphologically evaluated by Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) analyzes. hrough alkaline pretreatment it was possible to reduce the lignin fraction by 34.7% and the hemicellulose fraction by 23.52%. The biomass treated under the best conditions determined by statistical analysis was hydrolyzed and the saccharification kinetics was followed. The process was followed for a period of 96 hours, and it was observed that the 54.44% yield was achieved for a time of 72 hours, after which there was no further significant increase. The residues generated in the alkaline treatment step (black liquor) and enzymatic hydrolysis (residual biomass) were characterized by FTIR and thermogravimetric analysis. Respectively, which allowed us to observe the predominant presence of lignin in black liquor and cellulose in residual biomass These results can be considered satisfactory in the context of forest biomass and can be raised at a future laboratory scale to the pilot scale, with studies on the enzymatic hydrolysis 

2019
Descrição
  • HELDER KIYOSHI MIYAGAWA
  • ANALYSIS OF THE CONVENTIVE HEAT TRANSFER BY INTEGRAL TRANSFORMATION IN CHANNELS WITH WAVY WALLS

  • Data: 13/12/2019
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  • The hybrid numerical-analytical approach known as the Generalized Integral Transform Technique (GITT) is employed in solving the two-dimensional Navier-Stokes and energy equations in a wavy plates channel. The flow is considered laminar and incompressible for a Newtonian fluid with temperature-independent physical properties, while the walls temperatures are kept uniform along the channel length. The streamfunction-only formulation is adopted, which eliminates the pressure field and automatically satisfies the continuity equation. A thorough convergence analysis is performed for both the streamfunction and Nusselt number to demonstrate the method robustness. The verification of the present GITT results is also performed by comparing the centerline velocity, skin-friction coefficient, average temperature, and local Nusselt number with equivalent results from the COMSOL Multiphysics simulation platform, with overall good agreement. The influence of the governing parameters such as Reynolds number and wavy-wall amplitude on the velocity, temperature and entropy fields are also analyzed, demonstrating their importance for the convective heat transfer prediction and energy optimization

  • DOUGLAS ALBERTO ROCHA DE CASTRO
  • PROCESS OF PRODUCTION OF BIO-OIL AND BIO-ADSORBENTS THROUGH THE PYROLYSIS OF AÇAÍ SEEDS (Euterpe oleracea Mart.)

  • Data: 13/12/2019
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  • In this work we investigated the production of biofuels via pyrolysis, in laboratory scale, Semi-piloto and pilot, of açaí seeds (Euterpe oleracea) in Natura (SAIN) and impregnated with aqueous solution of sodium hydroxide (NaOH) 2 mol. L-1 (SANAOH).The experiments were carried out at 350, 400 and 450 °C, at 1.0 atm, using production units with capacities of 100 g, 1 kg and 143 kg. The experimental apparatus of laboratory and Semi-piloto constituted of a reactor of bosilicate and stainless steel, respectively, both with heating source via electrical resistance.The pilot unit of thermal cracking consisting of a reactor of stainless steel shirtless, being the source of thermal heating via burning GLP gas fed in a burner. The reactions produced non-condensable gases, organic liquid product (bio-oil + aqueous phase) and a solid phase (biochar). The bio was characterized by physicochemical analyses of acidity index, refraction, density, kinematic viscosity, FT-IR and GC-MS. The solid phase was characterized morphologically through the analysis of DRX, SEM, EDX, FT-IR, FRX and BET. The purpose of this process was to evaluate the influence of scale expansion, operational variables and chemical impregnation on yield on the quality of the products obtained, as well as variations in the physicochemical and compositional properties of liquid products (bio-oils and distilled fractions) during the reaction process.The reaction products showed average yields 5.91% (w/w), 33.45% (w/w), 23.55% (w/w) and 37.08% (w/w) for the bio, aqueous, gaseous and solid phases, respectively, for SAIN seeds, and 11.03% (w/w), 17.49% (w/w), 31.62% (w/w) and 39.84% (w/w) for the bio-oil, aqueous, gaseous and solid phases, respectively, for SANAOH seeds. It was observed that the yield of bio-oil increased and the yield of the aqueous phase decreased with the application of impregnation process at the investigated temperatures, it was also verified that the yields of biofuels were higher for lower temperature in relation to the experiments with SAIN, in all production scales. With the results found for the acidity index and for the kinematic viscosity of the bio obtained from the SANAOH, a maximum reduction of approximately 78% and 66%, respectively, was observed in relation to the bio obtained from the SAIN. The FT-IR analysis indicated the presence of hydrocarbons, oxygenates and biomass contaminants, as well as the reduction in the intensity of transmittance in the band regarding the connections of oxygenated groups. The GC-MS analysis showed a percentage in area for the peaks referring to hydrocarbons up to 2.25 times higher for the bio-oil obtained from the SANAOH, comparing to the hydrocarbon area of the bio of the SAIN.The morphological analysis of the biochar through the DRX demonstrated the existence of amorphous (SAIN) and crystalline (SANAOH) structures (mineralogical phase), while the SEM and EDX identified in the pores of the carbonaceous structure sodium crystals.The FRX corroborated the previous analyses, demonstrating sodium percentages of up to 32% (w/w) in the structural composition of the biochar. The FT-IR indicated the presence of functional groups commonly found in lignocellulosic material biomasses. BET had a surface area of less than 10 m².g-1. Laboratory Fractional Distillation produced liquid fractions in the range of gasoline, kerosene and light diesel, showing higher yields (above 20% w/w) for biokeresene phase and the maximum percentage in hydrocarbon area for biogasoline fraction estimated at 97.782%. Therefore, the application of the process of alkaline impregnation to the pyrolysis process of lignocellulosic biomass favors the conversion of biofuel products.
     

  • GILBERTO CALDEIRA BARRETO
  • METHODOLOGY FOR DETERMINING THE USABLE VOLUME OF THE ELEVATED WATER TANK OPERATED WITH PARALLEL PUMPS IN WATER DISTRIBUTION UNITS.

  • Data: 12/12/2019
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  • The determination of the usable volume of an elevated water tank is an important step in projects of gravity flow water systems. Engineers often apply traditional methods to design such water tanks for practical reasons, which, in their simplicity, do not consider important information, such as the physical and operational characteristics of the pumping stations. In this paper, an alternative procedure is presented for determining the usable capacity of an elevated water tank, in which are considered both the characteristics of the system and the operation of pumps in parallel, making an economic comparison with traditional methods. Five different designs of Gravity Flow Water Systems (GFWS) were sized and simulated, a case study with capacity to serve 10,000 inhabitants. The systems sized with the proposed method featured higher economic attractiveness than those sized with traditional methods.

  • ROMERO MOREIRA DE OLIVEIRA
  • PRODUCTION OF BIOFUELS THROUGH THERMO-CATALITICAL CRACKING OF RESIDUAL FAT WITH RED MUD CHEMICALLY ACTIVATED AS A CATALYST

  • Data: 04/12/2019
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  • In this work, a biofuels study was carried out by the pilot scale thermo-catalytic cracking process, of the residual fat from the fat boxes of the university restaurant of the Federal University of Pará (RU-UFPA), using activated red mud as a catalyst. The residual fat used in the experiments was treated by sieving, decantation, dehydration and storage, to be introduced into the cracking reactor. The red mud was subjected to a pre-treatment of dehydration in an oven at100°Cfor 24 hours, then subjected to a chemical treatment with 0,5M, 1M and 2M hydrochloric acid solution (HCl). Subsequently calcination of this material was carried out at1000°Cfor 2 hours, to be applied as a catalyst in the proportions 5%, 10% and 15% m/m. The cracking process was performed at a fixed temperature of550°C, and the generated PLO was collected by reaction time at 20, 40, 60 and 80 minutes, these were then characterized and subjected to fractional distillation. Distillation was performed on a Vigreux column with 12 stages, and condensed fractions were collected according to the distillation ranges of gasoline (45°C-175°C), kerosene (175°C-235°C), light diesel (235°C-305°C) and heavy diesel (>305°C), to be characterized later. The highest yield (PLO + gas) was from experiment 5 with 90%, prepared with 15% m/m catalyst treated with 1M HCl. Also presenting biofuels with better physical-chemical characteristics such as the acid value of gasoline in point 4 (9,4 mg KOH/g) and composites with the highest of 92.91% of total hydrocarbons for kerosene. .

  • ADRIANO SANTOS DA ROCHA
  • PREDICTION OF THE THERMODYNAMIC PROPERTIES OF SOYBEAN BIODIESEL, RAPESEED, ORDINARY DIESEL AND ITS BLENDS, AND ADDITIVE EFFECTS WITH DFT AND CANONICAL ENSEMBLE

  • Data: 08/11/2019
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  • Research Area: Transformation of Natural Resources

    In this study, we analyzed the thermodynamic properties of soy biodiesel, the most widely used biodiesel source among the world's largest consumers, and rapeseed biodiesel, a source with significant employment in the European Union and biodiesel additives. Also, the study of ordinary diesel was carried out to simulate the situations in which this fuel is in mixtures with different concentrations of biodiesel blends. The objective of this work is to study the thermodynamic properties of the fuels mentioned. Based, where possible, on experimental results to validate the expansion of theoretical results and point out the most appropriate methodology for this type of approach. To this end, computational simulations were carried out with theoretical support in the Density Functional Theory combined with the canonical ensemble model. The functional used in the simulations was type B3LYP with bases 6-31 + (d) and 6-311 + g (d), in addition to the composite method CBS-QB3. The calculated enthalpy values are higher in the biofuels in relation to diesel and the same happened with Entropy. When we analyze the change of Gibbs Free Energy, the largest variations were noted for biofuels. The coefficient of adiabatic expansion revealed lower degrees of freedom until 400 K temperature in both types of biodiesel, from that point all fuels have the same behavior for this property. The lowest relative error was found with the B3LYP/6-311 +g(d) method, with a value of 0.15% for the combustion of ordinary diesel. In relation to biofuels, the same method provided 0.48% relative error in the combustion of rapeseed biodiesel as the best result. Regarding the effects of temperature on these fuels, the results showed that both types of biodiesel are less susceptible to heating than ordinary diesel at all calculated points, always requiring more energy to raise their temperature. The results in the additives showed that the antioxidant pyrogallol that most interferes in the biodiesel properties

  • FRANCISCO XAVIER LIMA DA SILVA
  • PRODUCTION OF BIOSORESORVENTS FROM WEED FOUND IN THE AMAZON: APPLICATION IN THE REMOVAL OF BLUE METHYLENE FROM AQUEOUS SOLUTION

  • Data: 25/10/2019
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  • The present work evaluated the biosorption capacity of methylene blue dye by biosorbents produced from weeds, Cyanthilium cinereum (L.) H. Rob (CCLHR), Paspalum maritimum Trin, (PMT), Trachypogon sp. (TS) and Cyperus brevifolius (Rottb.) Endl. ex Hassk (CBHER) collected in the Amazon region in the city of Belém state of Pará, along the Campus of the Federal University of Pará. The influence of parameters such as biosorbent dose, contact,  initial dye concentration and potencial Hidrogeniônic were evaluated. The characterization of the biosorbents was performed using Scanning Electron Microscopy (SEM) to verify the material morphology and spectroscopy in the Fourier Transform Infrared (FTIR) region to identify the functional groups on the surface of the material. The time required for the system to reach equilibrium for all biosorbents was also evaluated. The adsorption isotherms were adjusted to the Langmuir and Freundlich model, and the adsorption kinetics data were adjusted to the pseudo-first-order and pseudo-second-order models. With the results of the characterization and procedures of biosorption, it was concluded that the analyzed species constitute potentially biosorbent for the removal of the blue dye of methylene of aqueous solution.

  • WENDERSON GOMES DOS SANTOS
  • STUDY OF THE PROCESS OF PRODUCTION OF BIOFUELS THROUGH PIROLYSIS OF TIRE WASTE

  • Data: 24/10/2019
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  • In this study, the pyrolysis process of waste tires was analyzed in the laboratory and pilot scales. In the lower scale, the temperature variation, the type of catalyst commercially obtained (CaCO3, Na2CO3 and Ca(OH)2), the type of catalyst synthesized / treated from industrial waste (LV 1M HCl, LV 2M HCl and zeolite of kaolin) and the concentration of the NaOH solution impregnated into the tire (0.5, 1 and 2M) in the yields and compositions of the tire pyrolysis oil (TPO). In the larger scale, the evolution of the physicochemical and compositional properties of the TPO’s during the thermal cracking process (T = 400 °C, T = 450 °C and T = 500 °C) was evaluated in order to obtain a liquid product with characteristics of fossil fuels and / or compounds of high commercial value. The results showed that the yield of the TPO's are influenced by the increase in process temperature, by the type of catalyst and by the chemical treatment in the raw material. Being the process at 500 °C and with kaolin zeolite as the catalyst which most optimized the process for the yield and production of aliphatic compounds in the TPO. The use of catalysts led to the reduction of aromatic compounds and sulfur compounds in the liquid fraction. On the smaller scale, the behavior of the aliphatic compounds in thermocatalytic processes and chemical impregnation of the raw material was strongly influenced by the composition of d-limonene in the oils of pyrolysis of tires. The results of the pilot scale allowed us to conclude that there were variations in the physicochemical and rheological properties during the cracking process, but tend to stabilize in 65 minutes of process, presenting low acidity and low viscosity. The main substances identified throughout the process were d-limonene, BTX (benzene, toluene and xylenes) and cymenes. In the fractionation of TPO’s, the fraction of gasoline (C8 to C10) and kerosene (C8 to C17) are essentially hydrocarbons, while light diesel (C15 to C21) and heavy diesel (C17 to C23) by heteroaromatics. It is also concluded that sulfur and halogen compounds tend to be separated from the light diesel range.

  • LIA PEREIRA PINHEIRO
  • STUDI OF THE PROCESS OF SEWAGE SLUDGE CRACKING IN DIFFERENT SCALES OF PRODUCTION, AIMING ALTERNATIVE WASTE UTILIZATION

  • Data: 24/10/2019
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  • This work had the main objective to study the process of thermal and thermal-catalytic cracking of sludge and sludge with residual fats from sewage treatment units, with highlight use of sewage sludge. The sludge was collected and treated by thermal drying and disintegration in a ball mill. Subsequently, the sludge was characterized physico-chemically and morphologically. The residual fats were collected and treated by dehydration and sieving. The experiments were carried out on a bench unit and a pilot cracking unit. Calcium hydroxide, sodium hydroxide and sodium carbonate were used as catalysts. After cracking, the Organic Liquid Products (PLOs) obtained were characterized by physicochemical and compositional analyzes. The cokes obtained were submitted to chemical and morphological characterization. In addition, fertility and heavy metals characteristics were investigated in the cokes obtained in the Pilot Unit. The highest yield in PLO in the bench unit, oily phase, around 38.69% in the 60% sludge heat + 40% residual fat experiment, at 450 ⁰C, group D. In the pilot unit experiments, the largest 12.43% PLO yield Oily Phase was given for experiment 03 (thermocatalytic cracking of sludge + residual fat from the SOCIPE Slaughterhouse, in the presence of Ca(OH)2, catalyst, 290 °C, with yields proportional to 4.27%, 4.28% and 3.88 %, respectively, in the collected aliquots, the temperatures of 188 ºC, 260 ºC and 290 ºC. The result of the chromatographic analysis of the Thermal experiment 60% sludge + 40% residual fat, the temperature of 450 ⁰C, group D, presented in the PLO composition 67.21%  hydrocarbons, 12.82% oxygenated compounds, 19.07 % of nitrogenous compounds and 0.90% of others. The highest coke yield (81.82%) was obtained in Experiment 03 in the pilot unit. The concentrations of metals investigated in the cokes of experiments 1 and 2 make it possible to apply to the soil without breaching the current Brazilian environmental legislation.

  • BRUNO MARQUES VIEGAS
  • PROPOSAL OF MATHEMATICAL MODEL AND ESTIMATION OF KINETIC PARAMETERS OF LEACHING AMAZON RED MUD THROUGH BAYESIAN TECHNIQUES

  • Data: 13/09/2019
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  • This work proposes the mathematical model and the estimation of the kinetic parameters of red mud leaching using the Markov chain Monte Carlo method with the Metropolis-Hastings algorithm. Firstly, the red mud, from the Amazon region, Brazil, was characterized and leached with sulfuric acid at 20 and 30% in v/v at the temperatures of 60, 80 and 90 ºC, in two different hydrometallurgical routes: calcined at 900 ºC and form in natura. During the leaching, samples were collected every 30 minutes, which were centrifuged to obtain the leachate (liquid phase) and the concentrates (solid phase). In the liquid samples, the leached quantities of iron and titanium were measured using the uv-vis absorption spectrophotometry technique. For the characterization of the solid phase, the X-ray diffraction and fluorescence techniques were used. Based on the shrinking core model, a mathematical model was proposed, in terms of a system of coupled differential equations, aiming to represent the kinetics of red mud leaching. The leaching mechanism of iron, titanium and aluminum oxides presented, on average, chemical reaction order values of 1.52; 2.96 and 2.05, respectively. The values of the activation energies presented values in the range of 64 to 176 (kJ / mol). The proposed mathematical model was validated when reproducing the experimental data and the use of the Bayesian statistic was adequate.

  • RAIMUNDO NONATO CARNEIRO DE SOUZA
  • Usage and transformation of natural resources. Line of research: Modeling and simulation of processes.

  • Data: 13/09/2019
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  • Avalanches can be considered as a percolation process. This hypothesis will be posted to evaluate if this approach is possible and what are its advantages. Some literature speculates that there is the possibility of considering avalanches as a percolation event. However, there is no clear distinction from the percolation model that these events describe, either a homogeneous or non-homogeneous process. This work deals with avalanche simulations as physical cases of percolation. To characterize the avalanches, two percolation models were simulated: homogeneous and heterogeneous. Simulations were developed to compare avalanches in both models. To perform these simulations, the probability of a site being open equal to 0.5 was used. The sizes and transients were measured for each avalanche in the different models. To close the work, experiments were carried out to create avalanches, in order to better calibrate the simulations using real avalanche data. For when comparing the simulated results with existing data in the literature, a typical behavior of a probability function was perceived. Given this behavior one can make predictions about the size of the avalanches. Analyzing the results obtained, it is possible that the behavior of avalanches created with non-homogeneous probability presented well defined characteristics, having larger values of size and transient. It was concluded that the non-homogeneous model has a high stability and is better in the evolution aspect of the avalanche, so with some adjustments the heterogeneous model can approach a real avalanche with greater accuracy.

  • JOHNNY GILBERTO MORAES COELHO
  • PREPARATION, CHARACTERIZATION AND APPLICATION OF ASPHALT MODIFIED BY WOOD/TIRE RUBBER: EXECUTION IN EXPERIMENTAL TRACK IN MACAPÁ-AP

  • Data: 06/09/2019
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  • In order to mitigate the damages caused to the environment, companies are adopting asphalts with recycled materials, known as ecological asphalt. The main objective of this work is a technological evaluation of the insertion of hard wood associated with rubber in asphalt coatings. Wood sawdust for construction use and ground tire rubber was used to prepare the wood/rubber compound. The available binder for the AC 50/70 produced by PETROBRAS came from the Fazenda Alegre field in the state of Espírito Santo and is processed by LUBNOR in Fortaleza, Ceará. The aggregates were supplied by the company ETECOM LTDA. A graduation used for mixtures for Range C of DNIT. The design of conventional asphalt mixtures and the incorporation of wood/tire rubber were defined and analyzed following a Marshall methodology. The characteristics and the capacity of the mixtures were evaluated: Marshall stability and flow, mixture density, air voids, bitumen-void ratio, resilience modulus, tensile strength. In a previous study, the mixing project consistent with the incorporation of the wood/tire rubber compound has a air voids equal to 3.7%, in this case, according to field studies, a relation of volume, and a decrease in the bitumen ratio may compromise the durability of the coating. A replacement of a portion of the mineral aggregates by the wood/tire rubber compound causes the asphalt mixture to increase flexibility in the asphalt mixing of an increase in resistance and reduction in the resilience modulus of HMA blends with the wood/tire rubber. For the projected asphalt mixtures, a lower ratio of resilient modulus and tensile strength (Mr/Rt) was obtained in hot mix asphalt (HMA) with a wood/tire rubber value of 5159.26, compared to conventional non-value HMA of 6607.67. The experimental section with asphalt concrete and the incorporation of wood/tire rubber to the dry process is not a difficulty in knowing more about when it is done conventional coatings and using modifiers. Issues involving research on recycled rubber and the reduction of unsanitary sawdust stock has been gaining ground and may be more than proven in this work, a new additive incorporated in asphalt pavements that reduces the degradation of the environment in which we live.

  • TARCIO DOS SANTOS CABRAL
  •  
    ANALYSIS OF RESISTANCE TO CAVITATION OF DIFFERENT COBALT COATINGS DEPOSITED BY THE CW-GMAW PROCESS
  • Data: 09/08/2019
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    The control of cavitation erosion wear is a hindrance concerning the maintenance of hydraulic equipment’s. The most used consumables to fill eroded areas are cobalt-based austenitic steels, specifically the commercially known as “Stellites”. The current study carried out analysis of the coatings deposited via the new CW-GMAW (Gas Metal Arc Welding – Cold Wire) process. Regarding the coatings deposition, three levels of the additional wire feeding speed were applied; 2,4; 4,8 and 7,2 m/min, without any change in the main wire speed, 8 m/min. The coating consisted in a three-layer deposit; the first two with an AWS ER 309L wire, via GMAW process, and the third layer employed the interaction between AWS ER 309L and Stellite 21 E wires, via CW-GMAW process. The coatings obtained an increase of cobalt values, with silicon and molybdenum variations, as well as the iron value reduction for each used feeding variation. The coatings were subjected to an accelerated erosion test, according to ASTM G32 Standards. The best obtained result corresponded to the coating with 7,2 m/min additional speed.
  • EMERSON CARDOSO RODRIGUES
  • PRODUCTION OF ZEOLITE MATERIAL FROM CAULIM OF AMAZON IN SEMI PILOT SCALE: APPLICATION IN COPPER ADSORPTION

  • Data: 27/06/2019
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  • This work aims to synthesize a zeolite product composed of zeolite type "A" plus sodalite using as filler kaolin starting material. The synthesis of Zeolites was carried out in a short time and in a system with agitation, in a reactor of stainless steel with a volume of approximately 0.001 m3 , that is, in semi-pilot scale. The system was heated by steam from a boiler. The X ray diffraction (XRD), X ray Fluorescence Spectrometry, Scanning Electron Microscopy (SEM), Granulometric Analysis and Differential and Gravimetric Thermal Analysis (DTA and TG) were identified and characterized. In the synthesis process the metakaolin was used as the source of silica and alumina, which was obtained at 600 ° C for 2 hours of calcination in a muffle furnace. A 5M sodium hydroxide solution was used as the sodium source. Several syntheses were carried out for a maximum duration of 180 minutes. Every 30 minutes aliquots of the product were taken for the study of reaction kinetics. The results of the zeolite syntheses were satisfactory and the product obtained was applied to the adsorption of Cu2+ ions, in which the influence of the variables: time, temperature, pH and adsorbent quantity were evaluated. The determination of the best adsorption model was performed by the Monte Carlo method via Markov Chain in simulation performed in the MATLAB software and through the Akaike Information Criterion the isotherms that were closest to the presented results were established. The results obtained were compared with other studies available in the literature and showed significant values, which characterize the process of zeolite production and adsorption as promising and efficient.

  • ANDRE LUIS MILEO FERRAIOLI SILVA
  • DEVELOPMENT OF GEOPOLYMERIC BINDING USING WASTE OF INDUSTRIES

  • Data: 14/05/2019
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  • The Rio Capim river region (Northeastern state of - Brazil) stands out nationwide due to its major reserves of kaolin, a clay mineral that is used for coating paper. Extraction of this mineral occurs at a depth of 20 meters, under clayey-sandy sediments from the Barreiras formation and a layer of hard kaolin, also known as flint or semi-flint kaolin, which is considered stable due to the high level or iron that renders it useless for coating applications. The objective of this research is to examine the development of geopolymers synthesized from wastes containing aluminum silicate. Geopolymers are inorganic polymers formed by activation of amorphous aluminosilicates (Al2O3.SiO2) that react in an alkaline medium. Red mud, the residue from the clarification stage of the Bayer process, was used as a source of aluminosilicate. Fly ash produced by the Bayer process boilers under conditions of 900 °C and 120KPa was also used as a source of aluminosilicate in the geopolymerization process. To increase reactivity in the reaction we evaluated the use of soft kaolin and flint kaolin calcined at 800 °C for two hours. Sodium hydroxide (NaOH, 5-30 M) and sodium silicate (Na2SiO3, SiO2/Na2O = 3,2) were used as the alkaline medium in the reaction. The wastes were characterized using FRX and DRX and the geopolymer samples were characterized through compression resistance tests, DRX, MEV and EDS. For the geopolymer derived from soft kaolin and fly ash, the best results were obtained for a SiO2/Al2O3 ratio of 2.5 and 3.23. For the geopolymer obtained from soft kaolin and red mud the best result was for a SiO2/Al2O3 ratio of 1.8 and 2.06. Calcination of red mud generated a gain in resistance of 5.4%. As for the flint kaolin and red mud polymer, the best results were obtained for the SiO2/Al2O3 ratios of 1.01 and 0.97. The geopolymerization reaction for the geopolymer obtained from flint kaolin and red mud when conducted at a temperature of 50°C presented an increase in compression resistance of 67.33% in relation to the synthesis performed at an ambient temperature of 29 °C. The synthesis of geopolymer cement derived from waste was shown to be an alternative to the use of Portland cement, given that geopolymer cement presented a greater resistance to compression and because the process of obtaining it involves less pollution.

  • DEBORAH ALINE TAVARES DIAS DO RIO VAZ


  • AN APPROACH FOR THE DESIGN OF DIFFUSER-AUGMENTED HYDRO AND WIND TURBINES USING THE BLADE ELEMENT MOMENTUM

  • Data: 30/04/2019
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  • It is known surrounding a turbine with diffuser may significantly increase its power. This effect has attained considerable attention as it shows theoretically the possibility of achieving a power coefficient about 2 times greater than an ordinary turbine. However, the effect of the diffuser efficiency has not been implemented into blade element momentum yet. Hence, this paper presents a novel approach to design diffuseraugmented hydro turbines considering the diffuser efficiency. Based on the blade element momentum, new expressions for the axial induction factor and thrust are obtained. In addition, both efficiency and load generated on a diffuser are considered to the extension of existing formulation to determine power coefficient in cases where diffuser losses are taken into account through efficiency (ηd) and area ratio (β). To assess the proposed model, a comparative evaluation of two different diffusers (flanged conical diffuser and flanged lens diffuser) is performed. Numerical and theoretical results are compared for a shrouded turbine equipped with 83% efficiency diffuser. The relative difference observed for the maximum power coefficient between the proposed model and an actuator disk model with diffuser is about 5.3%. For the hydro turbine with flanged conical diffuser, ix the mass flow rate is about 20% higher than for a bare turbine, while for the turbine with flanged lens diffuser the increase is only 2.4%. Also, for the flanged conical diffuser the power is increased by 53%. Furthermore, it is observed that the proposed blade element momentum with diffuser achieved good agreement with the numerical model, providing improved results compared to other models available in the literature.
  • EVELYN GABBAY ALVES CARVALHO
  • In this work, the importance and the need to make informed and rational evaluations of the externalities from the hydroelectric power generation are demonstrated, in order to estimate the real cost of the energy. The design, construction and operation of large hydropower plants projects are so recurrent in the Brazilian Amazon, demand great human, technological and financial resources, and also significantly impact and change the locations in which they are deployed. So, it is absolutely necessary that informed assessments, based on science and good technique, of externalities from the generation of hydroelectric energy be made, so that the real cost of the energy generated in a consistent and correct manner is defined. For this, a methodology was developed capable of accounting for the cost of externalities of hydroelectric plants. This study was restricted to the valuation of the externality resulting from the loss of fishing activity, chosen among innumerable externalities identified in the literature because it is the economic activity practiced by a large part of the population affected by the hydroelectric dams, therefore with economic and, mainly, social relevance. To value this externality, was used the opportunity cost method and time series to forecast future data. Only the valuation of this externality, which was not carried out during the Environmental Impact and Economic Feasibility Studies, the cost the energy increased between 1.7% and 2%, pointing out the need to calculate this and all other externalities generated by the implementation of a hydro power plant (HPP) and to incorporate its real values at cost, so that the enterprise is sustainable, balanced and feasible, allowing a realistic comparison with other sources of energy generation.

     

  • Data: 29/03/2019
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  • Keywords: externality, valuation, hydroelectric power plant, fishing activity.

  • DILSON NAZARENO PEREIRA CARDOSO
  • The general objective of the research was to develop alternative and useful materials within the construction industry, addressing a logic of valorization and reuse of solid waste, generated from construction sites and demolition, as well as the reuse of waste generated from metallurgical mining and mineral processing industry. The work was carried out on the construction waste (RCC), sulphated copper ore residue (RMCS) and the residue of circulating fluidized bed boilers from the combustion of coal to fly ash (CV). The materials were submitted to physical and chemical characterization through laser particle size analysis, x-ray fluorescence (FRX), diffraction and x-ray (XRD) ). The mortars produced were studied in the free state, ie without additives and also within the polyvinyl acetate (PVA) and styrene butadiene polymeric additive (SBR). The obtained products were physically characterized by the analysis of apparent porosity, (TG and DTG) and scanning electron microscopy (SEM). In the fluid state, rheological tests were performed in order to evaluate their behavior according to time ( The materials developed in this research presented technical properties approved under the ABNT norms, making them suitable for certain types of applications, in terms of laying and coating of walls floors and ceramic plates, respecting the technical characteristics of these materials.

     

  • Data: 21/03/2019
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  •  Reuse, Industrial waste, mortars, cement composites.

  • DIEGO HILDEBRANDO DOS SANTOS
  • The use of waste from the mining and metallurgy industry has become indispensable, so that this industrial segment is inserted in the concept of sustainable development. The work shows an application for red mud that, in combination with other materials such as silica and clay, produces a material with mechanical resistance and specific mass, which can be compared to the natural aggregates used by the civil construction industry. In the work all the raw materials and the final sintered product were submitted to x-ray diffraction analysis, scanning electron microscopy. Red mud and clay were also analyzed by x-ray fluorescence. The synthetic aggregates were produced with the intention of studying the relationship between the amount of silica used and the apparent specific mass, which had satisfactory results on sintered specimens at 1300 ° C, obtaining heavy aggregates with 10% silica and aggregates with values below 2 g/cm3 with 20% and 30% silica samples, characterizing so the aggregate as light. Therefore, the silica content, the amount of clay used together with the oxides present in the red mud, together with the ideal granulometry of these materials and the temperature, form a glassy phase that will give the aggregates important characteristics such as porosity, mechanical strength and apparent specific mass.

  • Data: 21/03/2019
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  • Red Mud, Sintetic Aggregates, Silica

  • JOSIEL LOBATO FERREIRA
  • ESTIMATION OF KINETIC PARAMETERS BY MARKOV CHAIN MONTE CARLO METHOD APPLIED TO METHANE AUTOTHERMAL REFORM PROCESS

  • Data: 28/02/2019
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  • The use of natural gas as an energy source has received considerable attention due to major advances in oil well drilling technology, its low pollutant emissions compared to other fossil fuels and the enormous availability of reserves. In this scenario, this work is concerned with studies regarding hydrogen production from natural gas, using a commercial alpha-alumina supported nickel catalyst in a reforming reactor. The overall process comprises feeding methane, oxygen and water vapor into the reactor. This process is known as Autothermal Reforming. From the obtained results, a kinetic model of reaction rates per component was solved. Therefore, it was possible to estimate all the kinetic parameters (reaction, equilibrium and adsorption constants). The estimations were performed at temperatures of 700 and 750°C for each molar feeding ratio employed. The Markov Chain Monte Carlo (MCMC) method was applied for the estimations. The acquired results are presented with regard to the estimated reaction rates, which were compared to the experimental rates. The estimated parameters were compared to results available in the literature.

  • DANIELA LIRA DE SANTANA
  • DRYING BY THE ATOMIZATION OF THE RED PITAYA JUICE (Hylocereus Costaricencis) CULTIVATED IN THE AMAZON REGION TO OBTAIN NATURAL DYE

  • Data: 08/02/2019
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  • The pitaya is a fruit of the species of epiphytic cacti of the genus Hylocereus (Berger) Britton & Rose, is a nutritious food source of bioactive compounds, presenting antioxidant properties. As a dye, it is a natural and alternative source for substitution of synthetic dyes, it has the red-purple color from the pigment betacyanin. However, natural dyes other than synthetics are easily oxidized by factors such as light and temperature, which potentiates pigmentary degradation. In this context, the aim of this thesis is to obtain a natural powder dye obtained from the red pitaya juice (Hylocereus costaricensis), dried in spray dryer, evaluating the influence of the operational variables and the quality of the final product. Drying occurred in a statistically planned manner, applying the Box Benhken planning. The input operational variables were: air temperature (110-130ºC), feed flow (4.17-12.5 mL.min-1) and carrier agent concentration (maltodextrin 20-DE) (10-30%) , the responses: process yield, moisture, betacyanin content and water activity. The Response Surface Methodology (MSR) was applied to analyze the response variables. The feed flow influenced all the responses, the air temperature influenced the process yield and the water activity, the concentration of the carrier agent influenced the betacyanin content and the moisture content. The optimum drying condition was estimated using the Global Desire Function (116 ° C, 4.17 mL, min-1, 10%). The dye in the optimum condition was evaluated through the sorption isotherms and thermodynamically through the isosteric heat. Stability was also evaluated in two types of environments (in the presence and under the light). The powdered dye was applied to food (yogurt), so that its potential as a food coloring was verified.

2018
Descrição
  • EDIMILSON DOS SANTOS MORAES
  • THERMODYNAMIC PROPERTIES: KEROSENE, BIOQUEROSENE, KEROSENE AND GASOLINE ADDITIVES, ESPLOSIVE SENSORS

  • Data: 23/11/2018
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  • In this work we perform the characterization of thermodybanuc potentials, obtaining predictions based on Density Functional Theory and statistical thermodynamics, through the canonical ensemble model. The study compared two theoretical methods, B3lyp/6-311 ++ g(d.p) and the semi-empirical method PM3, with the experimental values of the termodynamic property of Cp with the objective of validating the method with better precission. All simulations were perfomed conformation of the global minimus and optimizations of the molecules in the thermal equilibrium and for a temperature range of 0.5 - 1500 K. We will analyze the thermal properties, such as energy, enthalpy, Gibbs free energy, entropy, heat capacity at constant pressure with respect to temperature. In the combustion enthalpy the following methods were userd: B3lyp/6-311 ++ g(d,p), B3lyp/6-31+g(d), CBS-QB3, G3, G4 and the G3/G4 mean, obtaining results that show a good agreement with the experimental values, and verifying which of the methods best predicts the thermodynamic properties for reactions of combustion of the kerosene and bioquerosene. Also, a theoretical analysis was performed in DFT to calculate the thermodynamic properties of three molecules of additives. We simulated a composition of JP-8 with mixtures of the three additives togheter and separeted in order to observe its efficiency over other existing methods. Then, the termodynamics properties of the gasoline with additives were predicted under the same conditions already described. These calculated amounts included standard gasoline mixed with the following oxygenated additives: methyl tert-butyl ether, ethyl tert-butyl ether, diisopropyl ether, ethanol and methanol. it is possible to estimate some relevant fuel properties in the injection and combustion stage, showing substantial agreement with the experimental data, presenting relative errors of less than 2%, thus establishing an excellent method to calculate and predict the thermodynamic properties of the combustion reactions for with additives. in the last stage of this work, we present a theory of a simulated sensor device to identify explosive molecules that is of extreme interest for the area of public security in the fight against terrorism. For this, an armchair-type carbon nanotube (CNT) was modeled under the action of an external, longitudinal an uniform eletric field, causing the molecules of the explosives: 2, 4, 6 octogen and pentaerytritol tretanitrate. Turn around the CNT, behaving as a sensor depending on the temperature and the radius of rotation of the molecules. In this way, we study the physico-chemical properties of interactions of the molecules with the CNT  

  • WANESSA ALMEIDA DA COSTA
  • Extraction and Transesterification of the Residual Oil from Industrial Palm Kernel Cake with Supercritical Methanol

  • Data: 23/11/2018
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  • Palm kernel is an oleaginous seed found in fruits of Elaeis guineensis Jacq. and which represents one of the main oils consumed in the world, with an mean production of 18,59 million tons. Its main process is the extraction by mechanical pressing that generates, in the world, approximately 9.6 x 109 tons of residue also called residual cake. Since this residue can still present about 12% of remaining oil, supercritical fluid extraction (SFE) is presented as an alternative to the recovery of this oil. Soxhlet extraction was also performed to be compared to the SFE. Pressures of 150, 250 and  350 bar and temperatures of 40, 60 and 80 °C were used in the experiments. The raw material was characterized before and after the SFE by moisture, ash, fibers, proteins and lipids contents and the extracts were characterized by gas chromatography/mass spectrometry (GC/MS). The kinetic data were compared to the Sovová (2012) model and the condition of highest yield was used in the transesterification experiments. Molar ratios of 1:24 and 1:42 (oil: methanol), temperatures of 250, 300 and 350 °C, constant

    pressure of 200 bar and reaction times of 5, 10, 15, 20 and 25 minutes were used. The products were also analyzed by GC/MS to verify the transformation of triacylglycerols into methyl esters. The main results of this study were: SFE does not alter the centesimal composition of the raw material; the condition of highest yield was 350 bar and 80 °C; Sovová's model had the best fit to the kinetic data; the condition 1:42, 350  ºC was the one that obtained the highest content of esters (99.81%) in only 5 minutes of reaction. The transesterification of palm kernel oil in a supercritical medium is a valid alternative and presents advantages over the conventional method, however a more in- depth analysis considering the technical and economic limitations of this method is necessary.

     

    Keywords: Palm kernel. Supercritical fluids extraction. Residual cake. Supercritical transesterification. Biodiesel.

     


  • MARCELO GONCALVES MARTINS
  • THERMAL PROPERTIES OF (BIO) BUTANOL AND THE PHOTOCATALYSIS OF DIFFERENT TRIFENYLAMINE GRAFFIN WITH METALS FOR H2 GENERATION: APPROACH VIA THE FUNCTIONAL DENSITY THEORY

  • Data: 23/11/2018
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  • The electronic structures and optical properties of transphenylated doped graphene-functionalized triphenylamine using water as solvent were investigated theoretically to verify the efficiency of photocatalytic hydrogen production with the use of different doping. The density functional theory (DFT), applied in the Gaussian 09W software, using the B3LYP functional for all structures, and the base 6-31g (d) for the H, C and N atoms, and the based LANL2DZ, applying the Core Effective Potentials method, for the transition metals. Through the DOS of each structure it is observed that there was an increase of accessible states in the valence layer, in addition to the decrease of the gap for all the doping and for the structure with two and three radicals of Triphenylamine. Through the UV-vis absorption spectrum, there was an improvement in absorption in the range of 490 nm to 615 nm, for single doping with Ni, Pd or Os, and for mixed doping of Ni and Pd or Ni and Pd, Os, Ni and Pd or Ni and Pt, as new catalysts applied in the conversion of solar energy and the production of photocatalytic hydrogen, as they improve the absorption of solar energy in the range of interest and reduces the overpotential required for the production of hydrogen gas through water which can be used as an energy source. Another analysis, in the sense of energy generation, raised in this work will be to evaluate the thermodynamic potential of Butanol properties, along with their isomers, as complementary fuel or even substitute for ethanol and gasoline. For this, once again, the Gaussian09W allied to the DFT was used, but combined with the functional, hybrid B3LYP with the base set 6-311 ++ G (d, p) and 6-31 + G (d) , G3 and G4, as well as the compounds CBS / QB3. By means of the software, the optimization calculations were carried out in order to find the fundamental frequencies of the molecules, with the parameters found together with the set of bases and functional ones, we found the thermodynamic properties as: the specific heat molar at constant pressure, the enthalpy and entropy. All the simulations were at temperatures in the range of 100K-1500K and constant pressure of 1atm, in addition the combustion enthalpies of the butanol isomers were obtained, several ternary mixtures were also proposed where it was possible to compare the enthalpy variations between the fuels: gasoline , ethanol and n-butanol.

  • RACHEL MARGALHO BARREIRA VALENTIM
  • SYNTHESIS AND CHARACTERIZATION OF BIPHASIC CERAMICS OF  CALCIUM PHOSPHATES FROM NANOCELLULOSE OF THE AÇAÍ 

  • Data: 31/10/2018
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  • The remnants of the açaí agribusiness (Euterpe Oleracea Mart) are sources of lignocellulosic materials. The extraction of nanocellulose from the açaí integument constitutes viable raw material for the synthesis of biphasic ceramics (HA / β-TCP) by acid hydrolysis. After the fruit pulp is obtained a biomass that is divided into three fractions: sludge (parenchyma), fiber (monostelo) and endocarp. The integument is analyzed by MEV / EDS, through the endocarp of açaí of terra firme and of várzea presenting essential nutrients, to obtain ceramics of phosphates of calcium. The biocomposite (NC / HA / β-TCP) was characterized by MEV, presenting crystalline species on the surface of the nanocellulose; X-ray diffraction presenting HA nucleation attributed to type I cellulose and tricalcium phosphate (β-TCP) on the surface of cellulose type II; showing the growth of HA crystals on the surface of the nanocellulose. The FTIR analysis showed characteristic peaks of PO4-3, C1-H glycosidic deformation at 897 cm -1 attributed to cellulose, strong C-C conjugate binding at 1609 cm -1 attributed to lignin showing a decrease in content during the process. The results of particle size are in the nanometric dimension showing 643.50 nm as the most common value related to the results of the zeta potential presenting unstable particles producing particles aggregation and stable particles with modulus value greater than 20 mV. Due to the characteristics presented by the biphasic ceramic synthesized in this work it is suggested its application as biomaterial.

  • ABEL FERREIRA GOMES NETO
  • DENSITY FUNCTIONAL THEORY AND CANONICAL ENSEMBLE FOR THERMODYNAMIC ANALYSIS OF NATURAL GAS, SYNTHESIS GAS AND THEIR MIXTURES.

  • Data: 05/10/2018
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  • In this work we performed a thermodynamic characterization of natural gas, synthesis gas and of the mixtures of these two fuels, obtaining predictions based on the density functional theory and in statistical thermodynamics, through the canonical ensemble model. The study initially focused on verifies what method of the Density Functional Theory is more suitable for the thermodynamic analysis of natural gas, where properties, such as the following thermodynamic potentials, were obtained: internal energy, enthalpy, Gibbs free energy and entropy. After concluding that the B3LYP functional, along with the basis sets 6-311++g(d,p) corresponds to the most recommended method for the thermodynamic prediction of this fuel, the thermodynamic properties of the synthesis gas were analyzed, as well as the effects caused by the synthesis gas when mixed with natural gas. The results showed that the synthesis gas is shown as a possible anti-knock additive, where a mixture containing up to 30% of synthesis gas is capable of raising the resistance of natural gas to heating, reducing only about 15% of its energy released in the combustion.

     

    Key words: Natural gas; Synthesis gas; Density Functional Theory; Canonical ensemble.

2017
Descrição
  • PATRICIA DA SILVA HOLANDA
  • Assessment of hydrokinetic energy resources downstream hydropower plants

  • Data: 21/12/2017
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  • The maximization of the performance of hydropower projects by taking advantage of the remaining energy downstream of dams via the installation of hydrokinetic turbines is feasible. In this context, two case studies of the hydroelectric power plants are presented, one of large Tucuruí in the Tocatins river, Amazonia, and another of medium size Bariri in the Tietê river, in the Southeast of Brazil.In central hydrokinetic projects, the design of the rotor diameter and velocity of the water are fundamental and depend on the depth and velocity of the river, respectively. Thus, the Saint-Venant model has been applied to these areas of studies. The calibration of the model was performed by linear regression of the measured and simulated flow rates for both, resulting in a correlation of 0.99. Validation was performed for a point on the Tocantins river using velocities measured with an acoustic Doppler current profiler (ADCP). The measured velocities are comparable to the velocities simulated by the model. Thus, a power curve was generated for the measured flow rates and the simulated velocities for the point at which the velocities were validated, thus obtaining a correlation of 0.96. This same curve was used for estimates of velocity, calculation of the energy density, and defining a design velocity for Tucuruí HPP equal to 2.35 m/s and Bariri 2.25 m/s. After the design was velocity defined, 10 points were selected Tucuruí and 1 point Bariri for the location of hydrokinetic turbines. The velocities of these points were determined with the same method used for the validation of the velocities. The points were selected based on the channel downstream of the reservoir and at the end of the Bariri dissipation basin, with the largest depth and velocity, which are characteristics favorable for greater power generation. Considering the rivers depth and available manufacturing technology, the rotor diameter was defined for the large study in 10 m and for the medium 2m. After the design velocity was defined, the rotor design was implemented using the blade element method (BEM), allowing for the definition of an installed power curve of the turbine as a function of the river velocity. With this information, an installed capacity of 472 MW was estimated for the analyzed points, which is equal to 5.64% of the installed capacity of the UHE Tucuruí plant (8,370 MW). In terms of generated energy, the 10 turbines can generate 2.04 GW/year. These numbers demonstrate the potential for utilizing the remaining energy of hydroelectric plants.

  • ANDERSON MATHIAS PEREIRA
  • STUDY OF THE PROCESS OF THERMOCATALITICAL CROPPING OF BOVINE
    SEVO FOR BIOFUEL PRODUCTION

  • Data: 01/12/2017
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  • This work aims to study the use of beef tallow as raw material for the production of bio
    fuel through the process of catalytic thermal cracking reaction. Three catalytic thermal
    cracking experiments were carried out in a 143 liters reactor, operating in discontinuous
    mode at 450 °C at atmospheric pressure, using sodium carbonate (Na2CO3) as the catalyst.
    Two experiments were carried out with crude beef tallow (5 and 10 % Na2CO3 -
    mass/mass) and one with bovine tallow soap (5 % Na2CO3 - mass/mass). The organic
    liquid products obtained from the reactions were analyzed through physicochemical
    analysis and chemical composition. Fractional distillation was also realized in order to
    obtain fractions of petrol, kerosene and light diesel similar to petroleum. In order to follow
    the reactions over time, aliquots were withdrawn every 10 minutes up to a total of 10
    samples with the first point collected within 30 minutes of reaction. For the collected
    samples physicochemical analysis and identification of the chemical compounds were
    realized. The results showed a tendency to obtain higher yields in organic liquid product
    (OLP) using the catalyst in larger quantities with the crude sample. The chemical
    identification showed the amount of hydrocarbons present (paraffins and olefins) ranging
    from 89.28 to 92.23 % and oxygenates (ketones) from 7.77 to 10.72 %. After the
    distillations, a predominance was observed in the diesel fraction (235-305 °C) while the
    petrol and kerosene fractions were lower, this behavior was repeated in all experiments.
    Regarding the samples collected over the time of the reactions it is possible to verify an
    increase in the acidity index and formation of oxygenates up to 60/70 minutes indicating
    the occurrence of the primary cracking and then, until the end of the reaction, a decrease
    in these values evidencing the secondary cracking.

  • JOAO GUILHERME MOTA DE SOUSA
  • POTENTIAL FOR THE USE OF COPPER TAILINGS IN PAVEMENT

  • Data: 07/11/2017
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  • The mineral exploration activity in the Pará State generates millions of tons of waste deposited exposed to open air retained through a dam. The copper mine tailings increases every year and the possible rupture of the dam presents a risk of contamination to the environment. Rock mining for the extraction and processing of copper located in Sossego, Canaã dos Carajás, Pará State, Brazil, from 2012 to 2016, left more than 112 million tons of copper mine tailings of sulfated copper. The cost for the deposition of the waste added to the expense for construction of dams and the maintenance, besides the permanent risk to the environment are presented in this work. The main objective in this work is to verify that the residue of sulfated copper combined with laterite fine soil is suitable for the construction of layers of pavement. The soil mixing project varied between 30 and 50%. The geotechnical and physicochemical study served to characterize the residue of copper, soils and mixtures. The results obtained by means of the resilient modulus for the pure residue and mixed with laterite fine soil were 191 and 829 MPa, these values are positives to use the residue with technical and economical quality for the construction of layers of the pavement. The potential for the use of waste has a beneficial conclusion on the aspects technological, environmental and economic. The pavement of urban roads in cities in this region sum total 3,699 km, the waste consumption would reach 4,497,614 tons and for construction of base and sub-base layers for rural and urban roads would be 6,983,261 tons. This would be a total consumption of 11 million tons of waste.

  • FERNANDO ARACATI BOTELHO
  • STUDY OF THE INFLUENCE OF CALCIUM OXIDE AND MAGNESIUM OXIDE ADDITION IN THE NEUTRALIZATION AND STABILIZATION OF BAUXITE RESIDUE ALKALINITY THROUGH THE REACTION WITH CARBON DIOXIDE

  • Data: 20/10/2017
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  • The main problems related to the generation of waste are focused on the effects that this material can have on human health and the environment. And in the particular case of the bauxite residue (RB) generated through the Bayer process, there is a gigantic production of this residue besides the high alkalinity present, which is configured as a barrier to the reuse of this material in other processes. In this context, this thesis aims to analyze the influence of the addition of calcium oxide and magnesium oxide in the reduction and stabilization of the alkalinity of the RB, over a monitoring period. To this end, it was proposed to add Ca and Mg prior to the carbonation of the bauxite residue to increase the precipitation of stable components in the long run and thereby achieve a lower pH stabilization, i.e. carbonated the suspension of RB added CaO or MgO in a CO2 bubbling reactor and the residue was then stored in sealed vials, providing analyzes of this residue by monitoring the pH over time. Such storage is intended to boost the precipitation of stable compounds in this carbonated RB over time, thus favoring pH stabilization. The use of the additives of Ca and Mg to the residue is justified by a low concentration of these chemical elements in the RB itself, in its natural (in natura) form. Therefore, the alkalinity of the RB remained with a mean value of stabilization of pH≈9,5 for both the RB added of Ca and the added Mg, after a minimum period of 12 months of monitoring, proving the efficacy of the process.

  • PAULO ROBERTO RIBEIRO MARQUES
  • EVALUATION OF THE POTENTIAL OF SELECTED COPPER
    EXTRACTION USING MEMBRANE CONTACTORS FROM
    BIOLIXIVIATION OF ORE SULPHIDE

  • Data: 06/10/2017
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  • This work studied the bioleaching of copper sulphide ore (Calcopirite) in the presence of the
    bacteria Acidithiobacillus ferrooxidans (A. ferrooxidans) for its ability to oxidize ferrous iron,
    elemental sulfur and its reduced compounds, as well as the selective recovery of the leached
    metal through of the solvent extraction with hollow fiber membrane contactor using LIX 84I
    as an extractant. Biolixiviation assays occurred in acid media (pH =1.8) for 30 days using
    T&K solution as media culture of the species. The redox potential (Eh) and iron ion
    concentrations and other elements with time were monitored. The results show an extraction
    of 24.43% copper in the biotic media, 17.4% and 13% for the abiotic (T&K solution only)
    and control media. Solvent extraction using hollow fiber membrane contactors proved to be
    efficient in all experiments, reaching 85.23%, 82.39% and 81.93% at 90 minutes of operation,
    starting at an initial concentration of 1.34 g/L, 1.75 g/L and 2.86 g/L copper present in the
    control, abiotic and biotic media, respectively. None of the other ions present in both samples
    had an efficiency greater than 10%. Greater control of the pH in the process can minimize the
    effects of the complexation of the extractant with other ions in the medium, further increasing
    the efficiency of the process with respect to the metal of interest.

  • SEBASTIAO MARTINS BRUM
  • INFLUENCE OF GRANULOMETRY, SOLID CONCENTRATION AND
    MINERALOGICAL COMPOSITION IN THE RHEOLOGICAL PROPERTIES AND
    TRANSPORT VARIABLES OF BAUXITE PULP BY PIPELINE

  • Data: 04/08/2017
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  • The flow of solid-liquid mixture per pipeline depends on a large number of variables
    and parameters, which are related to the solid to be transported (granulometry,
    density, shape and hardness); to the carrier fluid (density and viscosity); the
    installation (inner diameter of the pipe, length, slope, roughness, inclination angles,
    singularities and etc); the mixture (density and solids concentration) and the system
    (tons of solid to be transported, flow velocity and pressure drop).
    In this context, aiming to understand the influence of Paragominas bauxite
    characteristics on pulp transport, a series of experiments involving pumping loop,
    permeametry and rheology were carried out in addition to standard granulometry
    tests, laser diffraction granulometry (Malvern) and characterization in MEV and XRF.
    Pulps named thick, thin and composite, in the concentrations of solids by weight
    (60%, 50%, 40% and 30%) were worked out in the tests.
    The objective of this study was to study rheological and flow of these fractions of
    bauxite pulp in turbulent transport by pipelines, verifying the effect of particle size,
    particle shape and composition and solids concentration on the drop of working
    pressure, in the determination of the friction factors and deposition velocities of the
    solids, in order to measure the interrelationships and similarities between these
    fractions.
    Finally, the results of experimental friction factors for Power L
    aw fluids (in the laminar and turbulent regimes) and Bingham fluids (in the laminar
    and turbulent regimes) are compared to the friction factors calculated according to
    Fanning's equation (1877); Dodge and Metzner correlation (1959); Buckingham
    Reiner's equation (1921) and empirical correlation developed by Darby & Melson
    (1981).
    By means of the results presented and discussed in this work, it was possible to
    evaluate the variables involved in the movement of these fractions of pulps through
    pipes, proving that these variables can be related in accordance with Graf,

  • RAIMUNDO NONATO DA COSTA COELHO
  • USE OF THE FAULT TREE ANALYSIS TECHNICAL FOR DETERMINING THE
    GENERALIZED HEURISTIC ALGORITM OF FAULT DIAGNOSTIC IN DIESEL
    ENGINES

  • Data: 29/06/2017
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  • The present work uses the Fault Tree Analysis (AAF) technique to determine the
    generalized heuristic fault diagnosis algorithm in diesel engines. The physical system
    (motor and its subsystems) is transformed into a structured logic diagram (the fault tree)
    where the various combinations of failures in the elements or items of the system are
    components of the motor that may result in an undesirable event. A set of fault
    diagnosis rules is built purely on the thermodynamics of the combustion process in the
    engine. It is sought the understanding of the dynamic interactions between causes and
    effects of failures that provides the indication of the trajectory of each until its root
    cause. With the help of a properly established Artificial Neural Network (ANN),
    inferences are made about the set of diagnostic rules to provide the operational
    condition of the motor under different test conditions and the results are presented in the
    form of tables and graphs, following the discussion and conclusion.

  • MARIA DA CONCEICAO DA COSTA VALENTE
  • PROCESSING EXTRACT FORMULATED ACAI ANTHOCYANINS (Euterpe oleracea Mart.) SPRAY DRYER TO DYE FOR OBTAINING POWDER

  • Data: 31/05/2017
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  • The present work aims to obtain açai powder dye produced by drying technique spray dryer. In the drying process, maltodextrin 20DE and modified manioc starch were used as carrier agents. It analyzed the drying of açaí extract based on the statistical design, considering as input variables: input air temperature and feeding volumetric flow rate on the response variables: humidity, powder recovery, anthocyanin retention and antioxidant activity the product. Input air temperature and feeding volumetric flow were found to be the statistically significant sources of variation on the responses. It has been estimated the optimum condition of drying based on statistical analysis and with the aid of simultaneous optimization technique called global Desirability Function From the conditions set out in this work, it was reached a great value Desirability Function acceptable and excellent. With getting the açai dye from its optimal point, the sorption isotherms were built. Thermodynamic sorption parameters were evaluated from the GAB model and through relations Clausius-Clapeyron and Gibbs-Helmholtz. The compensation theory enthalpy-entropy was properly applied to the isotherms, indicating that the moisture sorption phenomenon of dye in açaí powder is controlled by enthalpy. Was evaluated also stability and it is concluded that the photodegradation of dye acai powder occurred more slowly and evenly in the absence of light. The dye obtained can provide the use in various industrial forms (cosmetic, pharma and food).

  • EDNELSON DA SILVA COSTA
  • Abstract of Thesis presented to PRODERNA/UFPA as a partial fulfillment of the requirements for the degree of Doctor of Natural Resources Engineering (D.Eng.) 

    AVALIAÇÃO DE TENSÕES RESIDUAIS EM SOLDAS GMAW E GMAW-CW POR BIRREFRINGÊNCIA ACÚSTICA E DIFRAÇÃO DE RAIOS X


    Ednelson da Silva Costa
    Advisor: Prof. Dr. Eduardo de Magalhães Braga, D. Eng.
    Area of Concentration: Use and Transformation of Natural Resources.

  • Data: 26/05/2017
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  • In this work, welding were performed using the Gas Metal Arc Welding (GMAW)
    and the Cold-Wire Gas Metal Arc Welding (CW-GMAW) processes. The base metal
    were naval steel of classification ASTM A-131. The goal of this work was to determine
    the residual stresses for the CW-GMAW process and compare the results with that of the
    standard GMAW process. The residual stresses were determined using acoustic
    birefringence (BA) and X-ray diffraction (XRD) techniques. Microstructural and
    acoustoelastic analysis were performed in the base metal, in the as received condition, to
    determine the material rolling direction, acoustic birefringence (BA0) and acoustoelastic
    constant (CAE). These analyzes were required for the determination of the residual
    stresses using the acoustic birefringence techniques. For both welding models, the welds
    were bead plate performed in flat position using wire of class ER70S-6 as electrode. The
    electrode wire feeding speed used was 15 m/min, while the cold-wire was fed at the rates
    of 3 and 6 m/min, which are equivalent to 20% and 40% of the feeding rate of the
    electrode, respectively. The results showed that the processes produce different levels of
    residual stresses. For the GMAW-CW process, it was observed, with respect to the
    conventional process, that with 20% addition of cold wire the residual stresses decreased
    significantly and to 40%, reduced in smaller amount.

  • ELIZEU MELO DA SILVA
  • SOLUTION OF THE PROBLEM OF DRAWDOWN WATER TABLE OF AQUIFERS WITH VERTICAL OR HORIZONTAL WELLS NEAR STREAMS BY INTEGRAL TRANSFORMS

  • Data: 05/05/2017
  • Mostrar Resumo
  • Analytical or hybrid solutions based on the integral transformation technique are proposed to treat the problem of three-dimensional drawdown of confined, leaky or unconfined aquifers using fully penetrating vertical wells (FPVW) or radial collector wells (RCW) between parallel rivers with semi-permeable streambeds, with pumping rates varying in Time and initial condition varying in space. Favoring the technique employed, the scheme of ordering the eigenvalues was adopted and the extensive analysis of the convergence of the solutions was performed. A pseudo-stationary filter
    was used in the solution to absorb information from the source term, defined by the well, which considerably accelerated the convergence of the solution in series, eliminating the oscillating convergence caused by the Gibbs phenomenon. In order to validate the obtained results, comparisons were made with the results in the literature, where the efficiency of the proposed solution is demonstrated. It was verified the influence of the pumping rate on the rates of depletion, leakage, release and gravimetric drainage of the aquifer and observing how in long-term drainage activities the rates of river exhaustion are equal to the variation of the pumping rate, that is, stream depletion rates on long-term activities can be managed by itself pumping the well flow.

  • WASSIM RAJA EL BANNA
  • INFLUENCE OF FLOTATION RESIDUE COPPER ORE ON THE PHYSICAL AND MECHANICAL PROPERTIES OF THERMOSET MATRIX COMPOSITES AND BANANA FIBER (Musa Sapientum, Musacae)

  • Data: 24/03/2017
  • Mostrar Resumo
  • Growing environmental concern has driven the development of alternative materials from renewable resources. The vegetable fibers have been used in various economic sectors to replace synthetic fibers. Vegetable fibers offer advantages such as low cost, are not toxic and low density. Hard particles are added the polymer to increase the modulus, increase the thermal conductivity of the composite as well as can increase toughness. This work has as objectives the mechanical analysis (tensile, flexural and impact), physical analysis (apparent density, porosity and water absorption), flame retardance analysis (flammability test) and morphological electron microscopy (scan) of the pure matrix, reinforced polymeric composite with flotation
    residue of copper ore, the polymeric composite reinforced with banana fibers and the hybrid polymeric composite reinforcement banana fibers and residue copper. The manufacture of the composites was performed by the manual process (hand lay-up) at room temperature, under pressure and using a standard metal mold. 10 specimens of the test piece for each fraction and the pure polymer matrix were manufactured. The polymer composites were manufactured by following its mass fractions: the fibers vary by 1%, 2% and 3%, the copper residue ranging in 10%, 20%, 30% and 40%, and the hybrid composite with 1% and 2% fiber with addition of
    10% and 20% copper residue. The addition of the residue particles significantly increased the value of apparent density of the composite, in turn caused the decrease of the apparent porosity and water absorption. For the tensile tests the compound showed a significant better result was reinforced with 1% banana fiber with 38,50 MPa. Polymeric composites reinforced with 2% banana fiber, reinforced with 40% copper residue, and the hybrid composite with 2% fiber and 20% copper residue showed the best maximum flexural strain results with 156,03 MPa, 153,21 MPa and 198,16 MPa, respectively. And for the impact test, the composite that obtained the best results among the samples tested was the hybrid composite with 2% banana fiber and 20%
    copper residue with 21,26 kJ/m². The composites were not classified as flame retardant material, despite all they HB rating, they did not fit within the classification according to UL 94. The mechanical properties were evaluated from the tests carried out and the fractured surfaces were examined by scanning electron microscopy, in which the predominant mechanisms of failure in the composites that presented the best results were breaking of the fibers and for the fractions of 30% and 40% there was a better dispersion of the particles inside the matrix allowing the improvement of its properties.

    Keywords: Copper ore, Banana fibers, Composites hybrids.

2016
Descrição
  • ELISANGELA LIMA ANDRADE
  • OBTAINING BLUE DYE IN POWDER FROM GENIPAP: EXPERIMENTAL ANALYSIS OF INDUCED OXIDATION AND
    SPOUTED BED PROCESSES

  • Data: 16/12/2016
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  • With the advancement of new technologies in the dye market, it is already possible to
    find substitute alternatives like many artificial variations. Dyes are a vegetable base, like
    fruits, give the product a more natural appearance, as opposed to synthetic shades. In
    view of the context, the objective is to study the drying process of the aqueous dye
    mixture extracted from the unripe genipap fruit (Genipa americana L.) and the transport
    agent (cassava starch) in the spouted bed as a viable alternative to obtain dye powder,
    based on statistically planned experiments, evaluating the efficiency of powder
    production, stability, final moisture contents, as well physicochemical characteristics. In
    order to favor the fluid-particle contact and a cyclic standard movement, providing a
    control over the effective of the process, the inert particles (low density polyethylene)
    were used, for this technique it is possible to operate with large particles. Initially a
    physical characterization of unripe fruits of genipap is carried out and it extracts a blue
    dye from its endocarp by means of processes of induced oxidation and solvent, using
    water, oxygen and controlled temperature, like catalyst. In this sense, spouted bed
    drying of the solution composed of the blue dye mixture of genipap and cassava starch,
    leads to a significant reduction in water activity and, consequently, in its conservation
    and stabilization of its coloring properties, which makes it a viable alternative as It
    happens to the artificial blue dyes. To evaluate the stability of the dye extract against
    temperature and temperature degrades, and to study the rheological behavior of aqueous
    dye suspensions, as a function of concentration and temperature, aiming to establish as
    conditions for their transport in pipelines.

  • ELZA BRANDAO SANTANA
  • COATING LINSEED SEEDS (Linum usitatissimum L.) WITH BIOPOLYMER SUSPENSION IN SPOUTED BED

  • Data: 14/12/2016
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  • It was studied application of starch in natura come from manioc starch (Manihot esculenta Crantz) in obtaining a biopolymer suspension in the coating of linseed (Linum usitatissimum L.), using as coating equipment a conventional spouted bed. We analyzed the physical and chemical characteristics of cassava starch and seeds, as well as the physiological characteristics of the seeds in natura and covered. Tests were carried out to obtain the biopolymer suspension including preliminary immersion coating tests, to evaluate the acceptance of the seed structure by the polymer matrix, based on physical data (angle of repose). For the execution of the coating process, tests were performed to define the coating operation, which included adjustments in the operating system from the study of fluid dynamics to the pumping of the suspension to make it possible to define the conditions of operation of the spouted bed. Fluid dynamics curves were constructed with different charges and atomization pressures, obtaining the fluid dynamic parameters ΔPM, ΔPje, ΔPmj and Umj. From the fluid dynamics results, the operating conditions were determined for a load of 1000 g of seeds, spray pressure of 5 psi, distance of the spray nozzle of 14 cm above the fixed seed bed and air velocity in the range of 1,9 to 1,29Umj. To analyze the coating process used an experimental design type PCCR considering the input variables, air temperature (Tar) and flow rate of the suspension (Qs), and efficiency responses (η), growt of the particle (δ), loss grip (Pad), process evaporation rate (Ėp), germination (G) and germination speed index (GSI). To estimate an optimal point of this operation was applied to define desirability function, wherein the generated optimum for the overall desirability was 0.9630 with
    the seed bed operating at 51 °C and 12 mL/min, respectively. The obtained results show that the coating process was efficient in relation to the values obtained for the responses and also to maintain the physiological qualities of the seeds. In addition, to open precedents for application in foods since the seeds covered had water activity of 0,34, in front of an initial activity of 0,62 for the seeds in natura.

    Key words: Coating, Spouted bed, Biopolymer suspension, Seed physiology, Germination.

  • RICARDO BENTES KATO
  • STUDY OF INFLUENCE OF COPPER PROCESSING WASTE IN PROPERTIES OF ASPHALTIC CONCRETE

  • Data: 25/11/2016
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  • With the development of industrial society, the demand for raw material has been increasing steadily over the last decades. Linked to this development occurs the generation of residues, which in the case of copper approximately 1% of the soil is exploited and transformed into commercial copper, the other 99% become waste of the process, being deposited in containment basins, where it is estimated 90 million tons the quantity contained in the Canaã dos Carajás plant, from where the residue of this work was obtained. This leads to high construction and maintenance costs, as well as generating a hazardous environmental liability. The objective of this work was to evaluate the addition of copper mining residue in replacement of the small aggregate in CA. In the dosage design it was verified that the content of 10% of residue in substitution to the small aggregate, more precisely 7.73% (obtained by regression), as the proportion that best suited the Marshall properties, even with lower CAP content In relation to the others, fact this provided by the type of fines of the residue. In general, the measured mechanical properties were not altered by the presence of the residue, except for the fatigue data, where the 20% and 25% mixtures showed superior performance, mainly because the resilience modulus values were statistically the same. The rheological data, compared to Superpav classification, were also unchanged, as well as the coating thickness given in the simulation in the SisPav, being in the order of 5 cm. In analyzing the potential for the use of waste, a positive conclusion was reached regarding the technological, environmental and economic aspects, with the possibility of consumption of more than 1.500.000 tons in roads close to the project, besides the economy with CAP consumption and Portland cement for trace correction.

  • ELZELIS MULLER DA SILVA
  • STUDY OF RECYCLING SLUDGE ETA IN MANUFACTURING SYNTHETIC AGGREGATE MIXTURE WITH COAL ASH WHEEL.

  • Data: 22/11/2016
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  • The Wastes (sludge) generated in the Water Treatment Plants (WTP) and fly ash from coal-fired power plants cause problems by the amount and concentration of harmful substances in them. Thus, this study aimed to produce synthetic aggregates using sludge WTP Bolonha (Belém/PA) and fly ash assessing their technical and environmental viability. The composition of the synthetic aggregates consisted of a high concentration of these residues in mixture with clay to molding and sintering at temperatures of 1200 °C and 1250 °C. The physical, mineralogical and microstructural analyzes of the synthetic aggregate were performed. Two concrete were produced, one with synthetic aggregate, and other references. In concrete were assessed their physical and mechanical properties in fresh and hardened state, and their microstructures. For the characterization of the concrete waste leaching and dissolution testing were performed. Synthetic aggregates were classified as lightweight aggregate for its low bulk density (<2.0 g / cm3) according to NBR 7211 (ABNT, 2009). The concrete produced with sintered aggregate (AGS-02) at 1250 °C was classified as non structural lightweight concrete according to the norms NBR 6118 (ABNT, 2014) and NBR 8953 (ABNT, 2015). The concrete of waste were classified as waste class IIB, non-hazardous and inert by NBR 10004 (ABNT, 2004) and within the limits of Resolutions No. 20/1986 and 430/2011 CONAMA into rivers class 2. It is noteworthy the synthetic aggregate meets the demands of the construction industry, reduces the consumption of raw materials and offers an alternative to the final disposal of waste.
    Keywords: water treatment plant sludge; fly ash; synthetic aggregate; lightweight concrete.

  • CAMILA DE CASSIA RODRIGUES BATISTA
  • OBTENÇÃO DE EXTRATOS DA POLPA DE AÇAÍ (Euterpe oleracea) POR EXTRAÇÃO SUPERCRÍTICA: Isotermas de
    Rendimento Global, Atividade Alelopática dos Extratos, Enriquecimento de Antocianinas e Compostos Fenólicos

  • Data: 04/10/2016
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  • Açaí is one of the most popular functional foods of the Amazon, widely consumed in Brazil and became known in other countries, especially due to the many benefits it has for a wide use in the growing market for nutraceuticals. Açaí extracts derived have a number of components with antioxidant, vasodilatory, anti-inflammatory and energy. Among the appropriate technologies in the processes, supercritical technology has become advantageous to obtain extracts with higher quality, adding value to products and by-products of the process. This work presents as objective a study of the supercritical extraction process of acai pulp to obtain extracts rich in bioactive compounds. A evaluation of the variables of the supercritical extraction process with CO2 (temperature, pressure, and solvent density) of Açai pulp showed the conditions that maximize the amount extracts (lipid fraction) obtained, and enable the concentration anthocyanins in açai pulp defatted for subsequent extraction of these compounds. The extracts obtained from extraction with CO2 were evaluated for fatty acid composition and allelopathic activities. The overall yield isotherms showed that the maximum amount of extract obtained in the process was in the condition of 70°C/490 bar followed by the condition of 50°C/350 bar.

    Keyword: supercritical extraction, global yield, allelopathic activities, Euterpe oleracea.

  • ELINEIA CASTRO COSTA
  • Modeling and Simulation of fractioning of vegetable oils and of the liquid organic product from the thermal-catalytic cracking of palm oil in countercurrent multistage columns

  • Data: 03/10/2016
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  • In this work, a method was developed employing the commercial process simulator Aspen Hysys using a countercurrent multistage column to the fractioning/deacidification of vegetable oils applying processes such as liquid-liquid extraction, using ethanol as solvent, and supercritical fractioning, with CO2 as solvent. Palm and olive oil were used in the case study. Experimental equilibrium data of multicomponent systems published in the literature were correlated with both NRTL model and RK-Aspen models, the binary interaction parameters obtained from these correlations were used in the simulations.  The same procedure was applied to the fractioning/deacidification process of the organic liquid products (OLP) from the thermal-catalytic cracking of palm oil, using supercritical CO2 as solvent. The correlation of liquid-liquid equilibrium data of the systems showed that the NRTL model was able to suitably fit the experimental data for all the studied systems with RMSD between 0.15 to 1.72%. For all the S/F ratios analyzed, simulation results demonstrated, on the 10 stage column, that only when a mixture water+ethanol (12.41%) was used as solvent, the maximum acceptable level of neutral oil loss for industrial physical refining (5%wt) was attained. Correlation of experimental equilibrium data at high pressures indicated that the RK-Aspen model was able to properly fit the equilibrium data for all studied systems, with RMSD from 3.0E-05% to 0.58% for the liquid phase and between 2.0E-06% to 0,02% for vapor phase, for each composition of free fatty acid in the feed. The absolute mean deviations between the supercritical fractioning process simulated with 10 stages using the olive oil model mixture and the experimental results of supercritical fractioning of olive oil in a pilot scale column at 313K, S/F=20, with varying pressure and different fatty acid composition in the feed, were 2.25% for the yield of raffinate stream and 0.15% for the fatty acid concentration in the raffinate stream.

    The simulations of supercritical fractioning of OLP, with 10-staged columns, showed that the CO2 was able to deacidificate the produced fractions. For both proposed process diagrams with the column 1 using S/F=17 or 19, column 2 for all the studied S/F ratios, presented top streams (extract) containing compositions characteristic of kerosene from petroleum, with lower olefin and oxygenated content compared to the experimental fraction distillated within the same temperature range of petroleum kerosene published in the literature.

  • ROSSANA MARTINS MIRANDA
  • DEVELOPMENT OF A SANDWICH STRUCTURE BASED POLYMER, PRODUCED WITH MINING AND METALLURGICAL INDUSTRIAL SOLID WASTE, FOR APPLICATION AS INTERNAL PARTITION PANEL IN CONSTRUCTION

  • Data: 05/07/2016
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  • The rechearch proposed to use solid wastes from kaolin and bauxite mining and metallurgical regional industries in a composite of sandwich structure to apply as internal divider panel environments. The blade was of unsaturated polyester matrix, double jute fabric and, kaolin waste (20 wt% polyester) and, the core, of polyurethane expansive and red mud (bauxite waste at process to get alumina), from 0 to 50 wt% PU (increasing by 10 to 10 wt%), in a total of 6 different treatments). The tests carried out were: blade density (ASTM C271/271M – 11), sandwich structure bulk density apparent, sandwich structure porosity, tensile test on the blade (ASTM D5083-10), flatwise tensile test on sandwich structure (ASTM C297/C297M - 04), edgewise compressive test on sandwich structure (ASTM C364/C364M–07), flatwise compressive test on sandwich structure (ASTM C297/C297M - 04), 3-point flexural test on sandwich structure (ASTM D7250/D7250M – 06 e ASTM C393/C393M – 11), Charpy impact test on sandwich structure (ASTM D6110 – 10), flammability test on blade and on sandwich structure (UL 94 - 96) and sound transmission loss test on sandwich structure (ISO 140-3:1995 - E). The results indicated that the choise of polymeric matrices was suitable to reduce weight of such structure mainly the use of a PU expansive. Increasing red mud not contributed to significant increase of sandwich structure bulk density apparent. Kaolin waste reinforcement increased resistance to blade on tensile test. Red mud reinforcement reduced sandwich structure resistance on flatwise tensile, flexural and impact tests. Increasing of red mud didn’t influenced sandwich structure edgewise compressive and flatwise compressive tests but, but it´s use at this sandwich structure, decreased their resistance at the first test and increased at the second test. The PU high flammability was delayed for being cloistered by two blades of polyester and kaolin, proving flame retardant property of kaolin waste. And about sound transmission loss test, the increase of red mud increased that until 20% concentration, after this, stabilized at 25 dB (STC) until 50% red mud. The composite, as a whole, presented feature of a sandwich structure, with a low density core,
    x
    contributing to reduce structure weight and with higher resistant blades, providing it the desired structural feature to be a divider indoor panel.

  • ALVINO OLIVEIRA MELO
  •  

    SINTERIZAÇÃO DE PELLOTAS DE ARGILA, CARVÃO VEGETAL E CINZA VOLANTE DE CALDEIRA EM UMA CÉLULA DE COMBUSTÃO DE LEITO FIXO: ANÁLISE DA PROPAGAÇÃO DA FRENTE DE REAÇÃO DE COMBUSTÃO NO LEITO

  • Data: 20/05/2016
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  • Uma das grandes preocupações da humanidade atualmente gira em torno da preservação do meio ambiente, buscando-se, constantemente, por meio de estudos e pesquisas, alternativas que encontre um equilíbrio de convivência entre o homem e a natureza. Normalmente, as indústrias em geral, produzem resíduos, na sua maioria tóxicos, que prejudicam o meio ambiente, o homem e demais diversidades de vidas nele inseridas. Levando-se em consideração o contexto exposto acima, este trabalho faz um estudo de evolução da temperatura de combustão de uma mistura, em proporções previamente definidas, da cinza volante de caldeira proveniente de indústrias localizadas no Estado do Pará, argila proveniente das margens do Rio Guamá e carvão vegetal adquirido na região metropolitana de Belém-Pa. Os experimentos foram realizados em um reator de combustão, adquirido pelo Programa de Pós - Graduação em Engenharia de Recursos Naturais da Amazônia com a finalidade de avaliar-se o perfil de temperaturas de cada experimento durante o processo de combustão e se os valores dessas temperaturas seriam suficiente para desencadear o processo de sinterização das pelotas. Para realização dos experimentos, parâmetros como a velocidade de entrada do fluido (ar), diâmetros das pelotas (mistura de cinza volante, carvão vegetal, e argila moídos) e a granulometria do carvão vegetal cominuído, utilizado como combustível sólido, foram variados para cada experimento. O histórico de temperaturas foram registrados por um instrumento de aquisição de dados identificado como Paperless Recorder - PHL, e posteriormente plotados para análises. Foram obtidas temperaturas variando em uma faixa de 800 ºC a 1200 ºC que são valores suficientes para desencadear o processo de sinterização das pelotas. Os dados gerados pelo reator de combustão foram registados pelo "Paperless Recorder - PHL" e comparados com os resultados obtidos numéricamente.

  • DANIELLY DA SILVA QUARESMA
  •  

    ESTUDO DA SINTERIZAÇÃO EM REATOR VERTICAL DE LEITO FIXO: DESENVOLVIMENTO DE PROCESSO PARA PRODUÇÃO DE AGREGADO SINTÉTICO A PARTIR DE CINZA VOLANTE E BIOMASSA

  • Data: 19/05/2016
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  • Os agregados sintéticos vêm sendo empregados na construção civil como uma medida para redução do extrativismo mineral. Dentro desse contexto, a reciclagem de resíduos industriais configurasse hoje como a base da maioria dos processos de redução da exploração dos recursos minerais. Este trabalho apresenta a formulação de um processo de caráter ambiental e autossustentável do ponto de vista energético, parâmetros para desenvolver um processo para produção de agregado sintético a partir de cinza volante e biomassa, em reator de leito fixo. Dessa forma, para a produção do agregado foram confeccionadas pelotas com uma mistura de argila, cinza volante e carvão vegetal em proporções fixas. Preencheu-se o reator com 20% de pelotas (6,35 mm > pelota ≥ 4 mm) e 80% de carvão vegetal (3,36 mm > carvão ≥ 1,70 mm) classificados para promover a eficiência das reações de combustão e consequente processo de sinterização em diferentes velocidades de ar (Darcy a 20 ºC) de 0,0059 m.s-1 (1º Experimento), 0,0098 m.s-1 (2º Experimento) e 0,017 m.s-1 (3º Experimento). Por meio de difração de raios-X e microscopia eletrônica de varredura foi identificada a presença de mulita no agregado sintético. Este material é caracterizado como agregado leve, de acordo com as normas vigentes. Com os agregados sintéticos fabricou-se concretos leves, segundo a norma estabelecida, sem função estrutural na construção civil, mas com aplicações de resistência moderada, podendo ser utilizados em contrapiso. O processo se mostrou interessante para a sinterização de agregados com boa aderência à matriz de cimento, podendo ser facilmente controlado pela composição, granulometria, gradiente de temperatura e fluxo gasoso, reduzindo os impactos ambientais, à medida que o material produzido implica na não extração de agregados naturais.

  • NELSON DE SOUZA AMORIM
  • THEORETICAL AND EXPERIMENTAL ANALYSIS OF THE BIOHEAT TRANSFER IN SYNTHETIC TISSUES HEATED BY ULTRASOUND

  • Data: 14/04/2016
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  • The inverse problem of parameter estimation for the bioheat transfer problem in sintetic tissue was analyzed. Initially an experimental analysis was developed by heating a synthetic tissue using a ultrasound transducer. Different temperature profiles were obtained for 3 cases involving intensity variations: 1W/cm2 , 1.5W/cm2 and 2W/cm2 for 3 thermocouples positioned along the sintetic tissue. A mathematical model was develeped to represent the experimental problem. The solution of this model was obtained using the Classical Integral Transform Technique (CITT). The Levenberg-Marquardt Method was used to solve the parameter estimation for the attenuation of sintetic tissue. A comparison between experimental solution and the mathematical model was performed.

  • SIL FRANCILEY DOS SANTOS QUARESMA
  • ANÁLISE DA CONVECÇÃO NATURAL NO ESCOAMENTO LAMINAR EM CAVIDADES PARCIALMENTE PREENCHIDAS

    COM MEIOS POROSOS UTILIZANDO TRANSFORMADAS INTEGRAIS

     

  • Data: 07/04/2016
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  • Fazendo uso da equação de Darcy e suas correções de Brinkman e Forchheimer

    foi avaliada a convecção natural em cavidades parcialmente preenchidas com meio

    poroso, utilizando para isso a técnica da Transformada Integral Generalizada GITT.

    No primeiro momento foi analisado o problema do escoamento unidimensional em

    canal parcialmente preenchido com meio poroso, sem o efeito da convecção natural de

    forma a entender a metodologia de solução da técnica para problemas com interfaces

    fluido/poro. Foi usada a equação conhecida como Darcy-Brinkman-Forchheimer para

    descrever o perfil de velocidade no canal, utilizando-se da Técnica da Transformada

    Integral Generalizada GITT para resolver o problema proposto. Na segunda etapa do

    trabalho utilizou-se da GITT para estudar o problema da convecção natural térmica em

    cavidade retangular parcialmente preenchida com meio poroso, com paredes laterais

    diferencialmente aquecidas, utilizando a formulação matemática de Darcy-Brinkman-

    Forchheimer modificada para descrever o escoamento no meio poroso e no meio fluido,

    através do uso de um parâmetro binário que ao encontrar-se no meio fluido transforma a

    equação de Darcy-Brinkman-Forchheimer na equação de Navier-Stokes. A equação da

    conservação da energia foi utilizada para descrever o perfil de temperatura na cavidade,

    sendo possível avaliar a influência dos diversos parâmetros que caracterizam esse tipo

    vii

    de problema, como por exemplo, a influência da permeabilidade da camada porosa

    sobre o escoamento global e a transferência de calor global. Por fim foi realizado o

    estudo da convecção natural termosolutal em uma cavidade retangular parcialmente

    preenchida com meio poroso, que de forma resumida é a convecção natural derivada

    dos efeitos térmicos e de massa concorrentes entre si na formação do fluxo, foi utilizada

    a formulação de Darcy-Brinkman modificada para descrever o escoamento em toda a

    cavidade, que como já mencionado anteriormente assume a forma da equação de

    Navier-Stokes quando avaliada em meio totalmente fluido. A equação da conservação

    da energia foi utilizada para descrever o perfil de temperatura na cavidade e a equação

    da conservação das espécies foi utilizada para descrever o perfil de concentração. O

    estudo avalia também a eficiência da GITT em resolver sistemas de equações acopladas,

    com alto grau de não-linearidade envolvendo interface fluido/poro, foi usada a

    formulação Darcy-Brinkman-Forchheimer para descrever o perfil de velocidade no

    canal.

  • RUI NELSON OTONI MAGNO
  •  

    APLICAÇÃO DA TRANSFORMADA INTEGRAL GENERALIZADA EM MANCAIS RADIAIS OPERANDO COM FLUIDOS NÃO-NEWTONIANOS TIPO LEI DA POTÊNCIA

  • Data: 29/02/2016
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  • Neste trabalho é estudada a lubrificação hidrodinâmica de mancais radiais completos lubrificados com fluidos não newtonianos que obedecem a lei da potência. A formulação do problema é obtida a partir das equações gerais do movimento, após serem assumidas algumas hipóteses simplificadoras inerentes ao tipo de problema. O método da perturbação regular é aplicado nas equações governantes para determinação dos perfis de velocidade e em seguida à equação de Reynolds generalizada para fluidos não-newtonianos. Soluções para os casos limites foram obtidas analiticamente. Em seguida, a equação de Reynolds generalizada, na forma completa, é resolvida via Técnica da Transformada Integral Generalizada. Para o cálculo das formulações foram desenvolvidos códigos computacionais em linguagem FORTRAN 90/95 onde se utilizou a sub-rotina DBVPFD da biblioteca IMSL (2014). Os resultados para os parâmetros de desempenho operacional tais como o campo de pressão, a carga suportada, número de Sommerfeld, ângulo de ação, o coeficiente de atrito e escoamento lateral foram estabelecidos, e apresentaram excelente concordância quando comparados com resultados disponíveis na literatura, para diferentes excentricidades específicas, razões de aspectos e índices "n" para fluidos que obedecem a lei da potência. Resultados considerando três tipos de rugosidade, quais sejam, senoidal, meia onda e onda completa, também foram obtidos e apresentaram uma boa concordância com a literatura, sendo que a rugosidade tipo onda completa apresentou melhor desempenho, aumentando a pressão, a capacidade de carga, o escoamento lateral e uma diminuição no coeficiente de atrito.

  • DEIBSON SILVA DA COSTA


  • ESTUDO DA INFLUÊNCIA DE RESÍDUOS GERADOS PELA INDÚSTRIA DE MINERAÇÃO NAS PROPRIEDADES DE COMPÓSITOS DE MATRIZ POLIÉSTER REFORÇADOS COM FIBRAS NATURAIS

  • Data: 26/02/2016
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  • Neste trabalho foram confeccionadas placas de matriz de poliéster insaturada isoftálica puras, compósitos com fibras vegetais (sisal, malva e juta), compósitos com resíduos industriais (lama vermelha, caulim e cinzas) e compósitos híbridos com resíduos e fibras. Os resíduos foram utilizados com granulometria inferior a 100 mesh e as fibras nos comprimentos de 15 mm, dispostas randomicamente dentro da matriz. As fibras foram caracterizadas quanto às suas propriedades físicas, mecânicas e morfológicas. Os compósitos foram confeccionados pelo processo manual (hand lay-up) na forma de placas retangulares em molde metálico e prensados. Variaram-se as proporções das frações mássicas dos resíduos em 10 % até a saturação dentro da matriz, a fração mássica de fibras foi fixada em 5 %. Os compósitos foram caracterizados fisicamente (porosidade aparente, absorção de água e massa específica aparente), mecanicamente (tração, flexão e impacto), termicamente (termogravimetria - TGA), mineralogicamente (difração de raios-X - DRX), retardância à chama e morfologicamente (microscopia eletrônica de varredura - MEV). Constatou-se que com a inserção de resíduos e fibras nos compósitos houve incremento das suas propriedades físicas, mecânicas, térmicas e resistência a chama. As propriedades físicas de porosidade aparente, absorção de água e massa específica aparente aumentaram significativamente (6,7 % a 33 %) com a adição dos constituintes (resíduos e fibras). Nos compósitos somente com fibras e nos compósitos de (10 %) resíduos com fibras houve aumento (15 % a 95 %) de suas resistências mecânicas (tração, flexão e impacto). Evidenciou-se uma melhora na estabilidade térmica (10 % a 50 %) dos compósitos com adição dos resíduos. Somente os compósitos com lama vermelha apresentaram uma capacidade de retardo de chama, obtendo classificação V-2 de acordo com a norma UL-94. As análises morfológicas das superfícies de fraturas foram eficientes na identificação dos mecanismos de falhas e características presentes nos materiais. Os compósitos confeccionados apresentaram boas propriedades, o que os torna bons candidatos a certos tipos de aplicações, tais como painéis, forros, paredes divisórias e portas internas, revestimento interno de automóveis, calhas residenciais e outros tipos de aplicações desta natureza, respeitando as características de aplicações destes materiais.

     

  • AUGUSTO DA GAMA REGO
  • DESENVOLVIMENTO E APLICAÇÃO DE METODOLOGIA PARA AVALIAÇÃO DE DESEMPENHO HIDROENERGÉTICO DE SISTEMAS DE ABASTECIMENTO DE ÁGUA

  • Data: 19/02/2016
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  • A Tese de Doutorado teve por objetivo o desenvolvimento de metodologia e sua

    implementação em software para avaliação de desempenho hidroenergético de sistemas

    de abastecimento de água (SAA), bem como aplicação em sistema de escala real. A

    pesquisa foi executada em duas etapas: 1) foi modelado todo o processo de avaliação de

    desempenho hidroenergético, foram estabelecidas formulações para cálculo de perdas

    hidroenergéticas e implementada metodologia em software; 2) foi realizada a aplicação

    da metodologia em SAA de escala real, que necessitou de monitoramento de grandezas

    hidroenergéticas e de simulação computacional do mesmo SAA no Epanet 2.0. Os

    resultados da primeira etapa consistiram na definição de perdas hidroenergéticas, na

    conceituação de desempenho hidroenergético, na metodologia proposta

    (sequenciamento de ações e inerentes formulações matemáticas) para o cálculo de

    perdas hidroenergéticas e para avaliação de desempenho hidroenergético de SAA, na

    implementação da metodologia em software (batizado de SADHE2A) e no teste da

    metodologia com sucesso em SAA com dados sintéticos. Os resultados da segunda

    etapa foram consequência da aplicação da metodologia, com uso do SADHE2A – versão

    Beta, no SAA Guanabara (localizado na cidade de Ananindeua, Pará, Brasil), na qual

    foram verificadas perdas globais de água de 55,42%/m e perdas globais de energia

    elétrica consumida de 58,31% (ambos os desempenhos classificados como “ruim”) que

    ocasionaram impacto financeiro de -17.981,77 R$/mês (57,61% de toda a despesa com

    consumo de energia elétrica no SAA, desde a captação de água bruta até a entrega de

    água tratada ao consumidor). Por fim, a metodologia desenvolvida atendeu as

    expectativas da pesquisa para calcular as perdas de água e de energia elétrica consumida

    e avaliar o desempenho hidroenergético de SAA, com elevada potencialidade de uso no

    Brasil e no exterior.

  • NELIO MOURA DE FIGUEIREDO
  • MODELO DE GERENCIAMENTO DE USOS MÚLTIPLOS DA ÁGUA - UM ESTUDO DE CASO PARA A BACIA HIDROGRÁFICA DO RIO TAPAJÓS

  • Data: 04/02/2016
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  • Este trabalho trata de um modelo para gerenciamento de usos múltiplos da água, visando minimizar conflitos de uso, relacionados com a operação de sistemas de reservatórios em aproveitamentos hidrelétricos de bacias hidrográficas. O modelo SOUMA – “Sistema de Otimização de Usos Múltiplos da Água”, que consiste em um modelo estocástico de otimização baseado em programação não linear, foi desenvolvido e estruturado em GAMS (General Algebraic Modeling System) com o emprego do solver MINOS. Foram desenvolvidos dois modelos auxiliares. O primeiro é um modelo estocástico do tipo ARIMA para a previsão de níveis de água ou de vazões com dados pretéritos. O segundo é um modelo RNA do tipo chuva-vazão para a previsão de vazões afluentes a reservatórios. O modelo ARIMA na calibração e na validação apresentou R² médio acima de 0,90 e RMSE abaixo de 0,16, capturando de forma satisfatória o comportamento das séries de vazão e de níveis d’água. O modelo chuva-vazão que foi empregado na composição da vazão afluente ao reservatório, com a utilização de arquitetura RNA oferecendo 5 e 10 neurônios na camada escondida, apresentou melhor desempenho que o modelo ARIMA, com R² médio de 0,954 e RMSE médio de 0,098. O modelo SOUMA foi aplicado à bacia do rio Tapajós para o futuro Aproveitamento Hidro Energético – AHE São Luiz do Tapajós, Itaituba, PA. Foram criados sete cenários que serviram de parâmetros na otimização e minoração dos conflitos. Vazões afluentes ao reservatório foram obtidas e simuladas, para os cenários hidrológicos seco, médio e úmido e para os cenários climáticos El Niño, Neutro e La Niña. O dimensionamento hidroenergético do AHE foi aferido com base em MME (2004). Para geração de energia e profundidade de navegação, considerando as afluências dos cenários hidrológicos seco, médio e úmido, o SOUMA evidenciou, em relação aos níveis de referência dos cenários de navegação baixo, médio e alto, a ocorrência de profundidades abaixo da mínima, para gerações médias abaixo de 2.411 MW, 2.939 MW e 3.586 MW, respectivamente. Para geração de energia e capacidade de carga transportada, considerando as afluências dos cenários hidrológicos seco, médio e úmido, o SOUMA demonstrou, em relação aos níveis de referência dos cenários de navegação baixo, médio e alto, que gerações médias acima de 2.869 MW, 3.508 MW e 4.740 MW, respectivamente, não geram ganhos de capacidade de carga transportada e que gerações médias abaixo de 1.344 MW, 1.622 MW 2.056 MW, respectivamente, inviabilizam o transporte de carga. Para geração de energia e cota de inundação, considerando as afluências dos cenários hidrológicos seco, médio e úmido, o SOUMA mostrou, em relação aos níveis de referência dos cenários de controle de inundação baixo, médio e alto, a ocorrência de inundações a jusante, para gerações médias acima de 4.978 MW, 6.057 MW e 7.390 MW, respectivamente. Retiradas consuntivas são significativas apenas no período de junho a outubro. Considerando a média das demandas consuntivas mensais (145 m³/s), para afluências do cenário hidrológico seco, médio e úmido, o SOUMA evidenciou uma perda mensal na geração de energia elétrica de 50 MW, 47 MW e 44 MW, respectivamente. Os resultados aferidos evidenciam que os modelos desenvolvidos são ferramentas de fundamental importância à otimização operacional de sistemas de reservatórios com usos múltiplos, permitindo a otimização de gerações e de defluências em AHE, em períodos de cheia e de estiagem e de grandes demandas energéticas, com a manutenção de condições de navegabilidade em trechos a jusante de barramentos, através de simulações operacionais sustentáveis que minoram conflitos de uso. 

  • MARCIO CORREA DE CARVALHO
  • ANÁLISE MICROESTRUTURAL E DE PROPRIEDADES MECÂNICAS DE REVESTIMENTOS SOLDADOS POR SAW E
    GMAW-CW

  • Data: 29/01/2016
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  • Revestimentos depositados por soldagem tem sido largamente empregados em diversas areas da industria da mineração. Os processos de soldagem a arco, gás e metal ou metal inert/active gas (MIG/MAG) ou gas metal arc welding (GMAW), a arco, g´as e metal com adi¸c˜ao do arame frio ou gas metal arc welding and cold wire (GMAW-CW) e soldagem a arco submerso submerged arc welding (SAW), tˆem sido estudados com foco na aplica¸c˜ao de revestimentos resistentes ao desgaste. O uso de processos com alta produtividade e com flexibilidade para altera¸c˜ao da composi¸c˜ao qu´ımica mostra-se no caso do processo SAW como vi´avel, e promissor no caso do processo GMAW-CW, na aplica¸c˜ao de revestimentos resistentes ao desgaste. Neste trabalho foram investigados a microestrutura e as propriedades mecˆanicas de revestimentos resistentes ao desgaste obtidos pelo processo SAW e GMAW-CW em revestimentos de carbetos de cromo prim´ario (RCC) e revestimentos ferr´ıticos de segunda fase (RFe-SF). As t´ecnicas de caracteriza¸c˜ao estrutural convencionais como microscopia ´optica (MO) e espectroscopia de emiss˜ao ´optica (EEO), e avan¸cadas como difra¸c˜ao de raios X (DRX) e difração de elétrons retroespalhados (DERE) ou electron backscattered diffraction (EBSD), identificaram as fases (M7C3,M23C6, austenita e ferrita), defeitos (trincas, p´os não-dissolvidos e porosidades) e mecanismos de formação de defeitos (trincas de solidifica¸c˜ao e falhas de fabrica¸c˜ao) nestes revestimentos. As t´ecnicas de caracteriza¸c˜ao de propriedade mecˆanicas convencionais como microdureza e n˜ao convencionais como o teste de impacto abras˜ao compacto (TIAC) apresentaram-se como importantes ferramentas no estudo do desgaste de revestimentos depositados por soldagem. Os RFe-SF’s e RCC apresentaram um crescimento da perda de massa ao longo do tempo de ensaio. O RCC apresentou a menor taxa de perda massa, 48,1 % menor que o RFe-SF de maior raz˜ao de arame frio (rAF) e 61,4% menor que o RFe-SF de menor rAF. A taxa de perda de massa aumentou com a rAF. A taxa de perda de massa do RFe-SF de menor rAF ´e 34,6 % maior que a do do RFe-SF de maior rAF. A taxa de perda de massa em relação arAF, comportou-se de forma inversa em relação a microdureza, ou seja, quanto maior a microdureza menor a perda de massa.

2015
Descrição
  • CARLOS CELIO SOUSA DA CRUZ
  • HYBRID SOLUTIONS FOR FLOW AND HEAT TRANSFER IN CYLINDRICAL CAVITIES WITH ROTATING ENDS

  • Data: 04/12/2015
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  • Advisor: João Nazareno Nonato Quaresma Research Area: Use and Transformation of Natural Resources The present study evaluate numerically the heat transfer from the swirling flow cylindrical cavity with rotating ends. The generalized integral transform technique (GITT) was used for the solution of the two-dimensional Navier-Stokes equations in terms of streamfunction formulation and energy in the cylindrical coordinate system, in which the Boussinesq approximation was used for the buoyancy force. Results for the temperature and velocity fields are presented for a range of parameters: the Reynolds number (Re), 100 ≤ Re ≤ 2000; the Richardson number (Ri), 0 ≤ Ri ≤ 1; and the Prandt number (Pr), Pr = 1,0. The parameter counter rotation of the angular velocity of the top disk is, st, -1 ≤ st ≤ 1 and various aspect ratio of the cavity. The numerical part of the solution was solved using the DBVPFD subroutine IMSL library and the results generated are compared with data available in the literature showing excellent agreement.

  • BENEDITO LOBATO
  • ESTUDO DA MAGNETOHIDRODINÂMICA EM DUTOS USANDO TRANSFORMADAS INTEGRAIS

     

     

  • Data: 27/11/2015
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  • O presente trabalho apresenta o estudo da magnetohidrodin^amica para o escoamento de
    uidos em regi~oes com diferentes formas geometricas. O uso de tecnicas de transformadas
    integrais, no caso GITT, foi utilizada para obter soluc~oes das equac~oes da Quantidade de
    Movimento e da Transferencia de Energia. Em cada caso foi obtida uma soluc~ao hbrida
    (analtica-numerica) que foram tratadas com codigos computacionais que permitiram a analise
    dos campos de velocidade, de temperaturas e entropia. Os resultados foram comparados com
    os resultados obtidos em situac~oes classicas da literatura e tambem com resultados atuais,
    mostrando a e ci^encia e capacidade da tecnica utilizada.

  • LUIZ GABRIEL DA SILVA NASCIMENTO
  • "INFLUÊNCIA DA ADIÇÃO DE NANOTUBOS DE CARBONO NAS PROPRIEDADES MECÂNICAS DA LIGA AL-2%NI SOLIDIFICADA DIRECIONALMENTE"

  • Data: 27/11/2015
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  • Neste trabalho foi fabricada uma matriz hipoeutética de Al-2%Ni e adicionado nela concentrações variadas de Nanotubos de Carbono, com o objetivo de verificar a evolução da resistência mecânica do novo material processado. O processo de fabricação do material estudado se deu por fundição e resfriamento brusco unidirecional ascendente, com extração transiente de fluxo de calor e determinação de variáveis térmicas de solidificação. Imagens de Microscopia Eletrônica de Varredura mostram oarranjo dos nanotubos na matriz e com a Espectroscopia Raman foi possível determinar as bandas “D” e “G” e analisar a ação do processo sobre os mesmos. Por meio de ensaios metalográficos e mecânicos foi possível caracterizar o comportamento macro, microestrutural e as propriedades mecânicas. O acréscimo de pequenas concentrações de nanotubos aumentou significativamente a resistência mecânica da matriz.

  • ALINE CHRISTIAN PIMENTEL ALMEIDA SANTOS
  • DESENVOLVIMENTO DE MODELO DE SISTEMA DE INFORMAÇÕES GEOGRÁFICAS PARA AVALIAÇÃO DA EFICIÊNCIA HIDROENERGÉTICA EM SISTEMAS DE ABASTECIMENTO DE ÁGUA

     

  • Data: 29/10/2015
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  • Desenvolvimento de metodologia para a avaliação do desempenho hidroenergético de Sistemas de Abastecimento de Água (SAA) utilizando modelo de Sistema de Informações Geográficas (SIG) para auxiliar na tomada de decisão na operação de SAAs. O modelo desenvolvido em plataforma SIG possibilita o registro, a sistematização e a espacialização dos dados hidroenergéticos, a fim de evitar gastos excessivos com a energia elétrica agregada ao volume de água disponibilizado para consumo. Na 1ª Etapa foram identificados os parâmetros hidroenergéticos utilizados nos atuais métodos de gerenciamento de SAA e, em seguida, definidos os dados e indicadores para a representação espacial no modelo do desempenho hidroenergético por setor e por unidade de abastecimento de água. Na 2ª Etapa foi desenvolvido o modelo de gestão em SIG por meio da IDE Delphi XE5 e da plataforma TatukGis, em três fases: Construção do banco de dados geográfico (Fase 1); Construção do  módulo SIG (Fase 2) e Construção do módulo hidroenergético (Fase 3). A última Etapa (3ª Etapa) foi destinada a avaliação da funcionalidade do modelo desenvolvido, sendo simulado o funcionamento do SAA Bolonha, da Região Metropolitana de Belém, Pará, Brasil, o que permitiu a espacialização dos dados e indicadores para identificação dos setores com melhor e com pior desempenho hidroenergético. A ferramenta de construção de mapas de graduação de cores mostrou-se eficiente, permitindo a rápida identificação do melhor resultado do índice de consumo de energia elétrica no setor 9 da Zona Central (0,62 KWh/m³), bem como do pior índice de perda total no setor 7 da Zona Central (54,29%). Além da ferramenta para sinalização de alerta para os indicadores acima da meta estabelecida pelo usuário, que possibilitou a identificação do setor 7 com o pior índice de consumo de energia elétrica (0,85 KWh/m³). Com o trabalho foi constatado que o modelo SIGHE2A é uma ferramenta que permite e agiliza a avaliação do desempenho hidroenergético de SAA, especialmente por facilitar a identificação do problema e a tomada de decisão.

  • EDINALDO JOSÉ DE SOUSA CUNHA
  • "INFLUÊNCIA DO USO DE RESÍDUO DO PROCESSO BAYER NAS PROPRIEDADES TEROMECANICAS DE COMPÓSITOS DE BASE POLIMÉRICA REFORÇADOS COM FIBRA  DE CARAUÁ (Ananas erectifolius, L. Smith)"

  • Data: 15/05/2015
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  • Neste trabalho foram produzidos compósitos de poliéster isoftálico, utilizando-se
    a lama vermelha (LV) e fibras de curauá cardada (FCC) alinhadas e orientadas
    randomicamente, com e sem LV. Os compósitos foram fabricados pelo processo hand
    lay up e a moldagem por compressão. Foram produzidas placas de poliéster isoftálico,
    compósitos com a matriz de poliéster e LV e os compósitos com LV e FCC. Foram
    avaliadas as propriedades físicas, térmicas e mecânicas, dos compósitos. Constatou-se
    que o aumento de LV em 30% (v/v) melhora as propriedades mecânicas, térmicas e
    físicas dos compósitos. A adição de 25% (v/v) de FCC e LV a 5% (v/v) recupera em
    84% o módulo de elasticidade comparado ao compósito com 10% (v/v) de FCC e 5% de
    LV. Em compósitos com 5% de FCC orientado randomicamente e 30 % (v/v) de LV
    apresenta recuperação de 29% do módulo de elasticidade. Em compósitos com 25%
    (v/v) de LV evidencia-se efetivo retardo de chama. Constata-se a influência da LV na
    condutividade térmica dos compósitos de poliéster isoftálico, com aumento de (92% a
    0°C), (71% a 25°C) e (69% a 50°C) em compósitos com 30% de LV comparados com a
    matriz. A lama vermelha e a fibra de curauá podem ser insumos importantes na
    produção de compósitos de poliéster isoftálico, para a produção de painéis, paredes,
    divisórias internas e portas para construção civil.

  • MARCELO COSTA SANTOS
  • ESTUDO DO PROCESSO DE CRAQUEAMENTO TERMOCATALÍTICO DA BORRA DE NEUTRALIZAÇÃO DO ÓLEO DE PALMA PARA PRODUÇÃO DE BIOCOMBUSTÍVEL

  • Data: 17/04/2015
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  • As borras oriundas de refino de óleos vegetais são resíduos agroindustriais obtidos após a etapa de neutralização dos óleos vegetais, os quais constituem material de baixo valor agregado, além de ser um passivo ambiental para as agroindústrias, deste modo, vem se tornando cada vez mais atrativo o uso desses resíduos como matéria prima na geração de biocombustíveis. Este trabalho estuda o uso da borra de neutralização do óleo de palma como uma matéria prima alternativa, sob o ponto de vista, econômico e ambiental para o processo de craqueamento térmico-catalítico. Inicialmente foram realizados experimentos de craqueamento térmico e catalítico da borra de neutralização e do óleo de palma (em um único reator) e testes catalítico (no segundo reator de descarboxilação acoplado no primeiro), ambos em escala de bancada; posteriormente foram realizados experimentos de craqueamento térmico-catalitico e catalítico (somente na escala semipiloto) da borra de neutralização em escala semipiloto e piloto, utilizando diversos tipos de catalisadores (Na2CO3, CaCO3, alumina ativada, Zeólita HY, HZSM-5 e FCC). O produto líquido orgânico (PLO) obtido e as frações obtidas da destilação em escala de bancada e piloto foram caracterizados e comparados com a norma vigente. Os resultados obtidos em escala de bancada mostraram que o catalisador alumina ativada providenciou o maior rendimento em base úmida (83,70%), tendo o óleo de palma como matéria prima, no entanto, o biocombustível obtido com Na2CO3 apresentou melhor qualidade quanto às características físico-químicas. Na escala semipiloto, o maior rendimento foi o experimento térmico da borra (78,36%), seguido pelo experimento com 5% de alumina ativada (71,47%), porém o uso do Na2CO3 apresentou melhor qualidade quanto às características físico-químicas. Os experimentos na escala piloto mostraram o maior rendimento (71%) obtido com 15% de Na2CO3 na temperatura de 440 ºC. Os resultados obtidos das análises cromatográficas dos PLOs obtidos nesta escala confirmaram que o aumento no percentual de catalisador possibilitou a formação de um PLO rico em hidrocarbonetos (91,22%) contendo alifáticos, olefínicos, naftênicos e aromáticos e baixos teores de compostos oxigenados (8,78%). Enquanto a destilação do PLO do Experimento 5 possibilitou a obtenção de frações ricas em hidrocarbonetos e ausentes de compostos oxigenados.

  • ANDREIA DE ANDRADE MANCIO
  • PRODUÇÃO, FRACIONAMENTO E DESACIDIFICAÇÃO DE BIOCOMBUSTÍVEIS OBTIDOS VIA CRAQUEAMENTO TERMOCATALÍTICO DE ÓLEOS VEGETAIS

  • Data: 17/04/2015
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  • Neste trabalho, investigou-se as seguintes etapas: (1) etapa de produção dos biocombustíveis via craqueamento térmico catalítico; (2) etapa de fracionamento dos biocombustíveis e (3) etapa de tratamento dos biocombustíveis através da aplicação da extração líquido-líquido e da adsorção como alternativas a desacidificação dos biocombustíveis. Os resultados da etapa de produção de biocombustíveis mostram que a conversão variou de 86 a 97%. O rendimento em PLO aumentou de 41 a 76% e as propriedades físico-químicas como o NAT, diminuíram com o aumento da porcentagem de catalisador. Os resultados de GC-MS mostram que o aumento da porcentagem de catalisador promove um aumento no teor de hidrocarbonetos e diminuição de compostos oxigenados no PLO. As olefinas foram as principais classes de hidrocarbonetos presentes no PLO. O fracionamento do PLO mostrou que a principal fração destilada é a fração de diesel pesado seguida do diesel leve, atingindo rendimento máximo de 36,37 e 30,51%, respectivamente. Em relação à etapa de desacidificação por extração líquido-líquido, os resultados mostram que o aumento da concentração de água no solvente provoca uma diminuição na razão de partição do ácido. O álcool metílico foi o único solvente que apresentou aumento na sua capacidade de remoção de AGL com o aumento da temperatura. Em relação à desacidificação das frações destiladas por adsorção, os resultados indicam que as lamas vermelhas ativadas quimicamente com 0,25, 1 e 2 M HCl apresentam alto potencial para aplicações nos processos adsortivos de AGL, uma vez que o qt destes adsorventes foi superior a 2000 mg/g.

  • HELIO DA SILVA ALMEIDA
  • "PRODUÇÃO DE BIOCOMBUSTÍVEIS VIA CRAQUEAMENTO TÉRMICO-CATALÍTICO DE RESÍDUOS SÓLIDOS DE CAIXAS DE GORDURA COM CARBONATO DE SÓDIO E LAMA VERMELHA ATIVADA TERMICAMENTE"

  • Data: 16/04/2015
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  • Este trabalho teve o objetivo precípuo de estudar a obtenção de biocombustíveis a partir do processo de Craqueamento Térmico-Catalítico em escala piloto, a partir da gordura residual removida das caixas de gordura do restaurante universitário da Universidade Federal do Pará (RU-UFPA). A gordura residual foi coletada e tratada por peneiramento, desidratação e decantação, e introduzida na unidade piloto de craqueamento. Foram utilizados como catalisadores o carbonato de sódio e a lama vermelha ativada termicamente a 1000 C°, material rejeito da produção de alumina da empresa HydroAlunorte, que também se trata de um passivo ambiental. Após o craqueamento, o Produto Líquido Orgânico obtido foi caracterizado e destilado em escalas de laboratório e piloto, obtendo-se bicombustíveis na faixa do bioquerosene, biogasolina, diesel leve e pesado. Adicionalmente, investigou-se o consumo de água potável do referido restaurante e a geração de esgoto, determinando-se o per capita de consumo de água, o coeficiente de retorno de esgoto, a carga poluidora e o equivalente populacional. O maior rendimento em PLO, em torno de 82 %, foi obtido com 15% de catalisador carbonato de sódio. O índice de acidez do PLO (14,97 mg KOH/g) apresentou um valor considerado baixo e bastante satisfatório quando comparado a valores obtidos na literatura. Os resultados cromatográficos do experimento com 10% de carbonato de sódio apresentaram elevado teor de hidrocarbonetos PLO (78,98%), querosene verde (92,64% de hidrocarbonetos) e diesel leve (90,21% de hidrocarbonetos). Os resultados obtidos denotam viabilidade na produção dos biocombustíveis, a partir da gordura residual tratada das caixas de gordura.

  • LORENA GOMES CORUMBA
  • "Avaliação da qualidade de sementes de Vigna Unguiculata(L.) Walp. após processo de secagem em leito de Jorro"

  • Data: 31/03/2015
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  • A variedade de feijão-caupi (Vigna unguiculata L. Walp.),conhecida como
    feijão manteiguinha, é nativa da região Amazônica, seu cultivo é realizado
    principalmente por pequenos produtores, onde predomina a agricultura familiar. A
    qualidade fisiológica das sementes de feijão manteiguinha, no que diz respeito ao poder
    germinativo e índice de velocidade de emergência, estão diretamente ligados ao teor de
    umidade nas sementes, por tanto, são necessários estudos que avaliem o comportamento
    das sementes deste tipo de feijão quanto ao seu potencial higroscópico e às condições de
    secagem. Com o intuito de contribuir para melhorias na produtividade agrícola de
    feijões-caupi, o objetivo principal deste trabalho foi avaliar a qualidade de sementes de
    feijões manteiguinha, após processo de secagem em leito de jorro convencional. Neste
    sentido, primeiramente foram definidas as características físicas, químicas e fisiológicas
    das sementes in natura seguindo para obtenção de suas isotermas de sorção de umidade
    nas temperaturas de 40, 55 e 70 °C. Os parâmetros termodinâmicos de sorção, como
    calor isostérico, entropia e variação da energia livre de Gibbs, foram avaliados a partir
    do modelo de GAB e por meio das relações de Clausius-Clapeyron e Gibbs-Helmholtz.
    A teoria de compensação entalpia-entropia foi adequadamente aplicada às isotermas
    indicando que o fenômeno de sorção de umidade nas sementes de feijão manteiguinha é
    controlado pela entalpia. Para dar seguimento ao processo de secagem foram definidas
    as condições de operação do leito de jorro por meio da análise dos parâmetros
    fluidodinâmicos (queda de pressão máxima, queda de pressão no jorro estável, queda de
    pressão no mínimo jorro e a velocidade de mínimo jorro). Na execução dos ensaios de
    secagem foi aplicada a técnica de planejamento de experimentos Box-Behnken e por
    meio de análise estatísticas dos dados experimentais foi possível avaliar influência das
    variáveis de entrada: Temperatura do ar (Tar), velocidade do ar (Uar) e tempo de
    secagem (t), sobre as respostas, razão de umidade (XR), percentual de germinação (G) e
    índice de velocidade de emergência (IVE). O ponto ótimo do processo de secagem,
    estimado pela função desejabilidade global, foi obtido quando o leito de partículas
    operava na temperatura e velocidade do ar de secagem de 57°C e 0,934 m/s,
    respectivamente, por um período de 240 minutos. Nestas condições são obtidas
    sementes com umidade final 0,12 kg de água/kg de sólido seco, germinação de 82,53%
    e índice de velocidade de emergência de 14,73.

  • FRANCISCO CARLOS LIRA PESSOA
  • DESENVOLVIMENTO DE UMA METODOLOGIA PARA REGIONALIZAÇÃO DE CURVAS DE PERMANÊNCIA DE VAZÔES NA AMAZÔNIA LEGAL

  • Data: 30/03/2015
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  • A ausência ou a insuficiência de dados fluviométricos de séries longas e confiáveis, devido a fatores físicos e/ou econômicos, é um dos principais desafios enfrentados em estudos hidrológicos.Com o intuito de contornar esse problema, na presente Tese, foi proposto a aplicação do método de regionalização de curvas de permanência de vazões. Nesse contexto, a hipótese principal foi dividir a região da Amazônia Legal em regiões homogêneas, definidas pelos métodos de análise de agrupamento hierárquico de Ward e difuso Fuzzy C-Means, e para cada uma, formular modelos regionais de curvas de permanência de vazões. Para os dois métodos de análise de agrupamento, a distância euclidiana foi usada como medida de similaridade, e as variáveis explicativas da vazão (área de drenagem, precipitação anual média, comprimento e desnível do rio), foram usadas como dados de entrada. Foram obtidas 4 regiões homogêneas por intermédio do método de Ward e 14 regiões por Fuzzy CMeans. Curvas de permanência foram construídas para cada uma das 214 estações fluviométricas distribuídas em suas respectivas regiões, e calibradas em função de 6 modelos matemáticos (linear, potência, exponencial, logarítmico, quadrático e cúbico). Para cada região homogênea formada pelos métodos de análise de agrupamento, foi formulado um modelo regional de curvas de permanência de vazões, utilizando-se análise de regressão múltipla, relacionando os parâmetros do melhor modelo matemático calibrado com as características físicas (área de drenagem, comprimento e do rio) e climática (precipitação anual média) das bacias. Os modelos regionais obtidos foram validados por meio do método “Jack-Knife cross validation”. Os índices de desempenho encontrados - valores de NASH ≥ 0,75 em mais 62% dos casos, situando-se na faixa de desempenho de aceitável a bom - permitiram concluir que o método Fuzzy C-Means foi o mais indicado para a formação de regiões hidrologicamente homogêneas de vazão. Os modelos regionais desenvolvidos para cada
    uma das regiões formadas, apresentam-se como uma boa alternativa na modelagem de curvas de permanência de vazão para médias e pequenas bacias sem dados de vazão na região da Amazônia Legal.

     

  • ERIKA MILENE PINTO DE SOUSA
  • "EXTRAÇÃO, ESTABILIDADE, REOLOGIA E HIGROSCOPICIDADE DO CORANTE DE PITAYA (HYLOCEREUS COSTARICENCIS)"

  • Data: 04/03/2015
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  • Com o avanço de novas tecnologias o mercado de corantes naturais vem se expandindo
    com o objetivo de substituir os corantes artificiais utilizados, considerados prejudiciais à
    saúde. Os corantes naturais a base de frutas, conferem ao produto uma aparência mais
    natural, ao contrário do que acontece com as tonalidades sintéticas. Nesse contexto,
    realiza-se a extração do corante de pitaya, contido na polpa do fruto, por imersão em
    água destilada, em seguida faz-se a caracterização física e físico-química da polpa, o
    estudo da estabilidade a luz e a temperatura da concentração de betacianina e da cor do
    corante, quantificando os teores de betacianina por meio de espectrofotometria UV e da
    cor por colorimetria triestímulo, utilizando o sistema CIE L*a*b*. Avalia-se também o
    comportamento reológico da polpa da pitaya diluída em água destilada na proporção de
    1:1 por meio de modelos matemáticos com auxílio dos programas ReoWin e Statistica®
    7.0. Por fim, é feito o estudo da higroscopicidade do corante em pó obtido por
    liofilização em diferentes concentrações de maltodextrina, analisando também o corante
    puro, verificando através de curvas de sorção as melhores condições de armazenamento
    para corante de pitaya.

2014
Descrição
  • OSSALIN DE ALMEIDA
  • CONCENTRAÇÃO DE PRINCÍPIOS ATIVOS DE PRODUTOS NATURAIS VIA EXTRAÇÃO COM DIÓXIDO DE CARBONO SUPERCRÍTICO, EXTRAÇÃO COM SOLVENTES E ADSORÇÃO DE SOLUÇÕES DILUÍDAS EM LEITO FIXO: BIOENSAIOS ALELOPÁTICOS E ANTIFÚNGICOS

  • Orientador : NELIO TEIXEIRA MACHADO
  • Data: 18/12/2014
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  • Descreveu-se por meio de extrações por fluido supercrítico e por isotermas de adsorção do extrato bruto da raiz de Derris urucu. Nas extrações por SFE, foram avaliados os teores de rotenona e de deguelina em três condições experimentais (C1: T = 35 oC,  P = 120, 220 e 300 bar; C2: T = 40 oC, P = 120, 220 e 300 bar e C3: T = 60 oC, P = 120, 220 e 300 bar). Os teores médios de rotenona e deguelina da composição química dos extratos obtidos por SFE foram de 23,30 e 18,49% (T = 60 °C, P = 300 bar e t = 90 min), correspondentes a 93,16 e 73,97% do teor total contido na amostra in natura. No processo de adsorção em leito fixo, usando alumina ativada a 550 °C como adsorvente, os dados experimentais de adsorção se ajustaram bem ao modelo de Langmuir com R2 = 1,0000, e EMR = 0,45%, em 136,14min. O fator de separação RL = 0,0952 foi favorável, encontra-se na faixa entre 0 e 1. 

  • JEAN DA SILVA RODRIGUES
  • ESTUDO TEÓRICO E EXPERIMENTAL DO PROCESSO DE INFUSÃO DE RESINA APLICADO A FABRICAÇÃO DE COMPÓSITOS DE MATRIZ POLIÉSTER REFORÇADOS POR FIBRAS NATURAIS DA AMAZÔNIA

  • Data: 26/09/2014
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  • Neste trabalho foram produzidos compósitos de matriz de poliéster insaturado reforçados por fibras de curauá, juta e palha da costa, dispostas na forma de tecido em estilo plano e fibras alinhadas. Os compósitos foram fabricados pelo processo de infusão de resina, estudando-se os principais parâmetros que governam o método de fabricação, como a permeabilidade e porosidade do reforço e arquitetura de infusão. As fibras naturais foram caracterizadas quanto às suas propriedades físicas, morfológicas e mecânicas. Os compósitos reforçados com fibras de curauá foram fabricados utilizando-se as fibras in natura e tratadas em solução alcalina de NaOH em diferentes concentrações. Os compósitos foram caracterizados em ensaios de resistência à tração e impacto Charpy, além da determinação de suas propriedades físicas, como massa específica, porosidade e frações volumétricas dos constituintes. Os resultados demonstraram que os compósitos que obtiveram melhor desempenho em tração e impacto foram aqueles reforçados com fibras alinhadas de curauá, fabricados sob vácuo de 101,3 kPa. A avaliação da seção transversal dos corpos de prova mostrou que os compósitos podem apresentar saturação parcial dos fios ou fibras de reforço em função do nível de vácuo utilizado, principalmente nos reforços em forma de tecido com diâmetro de fios relativamente maiores. O processo de infusão se mostrou um bom método de fabricação de compósitos reforçados com fibras naturais, pois, além de ser ambientalmente mais favorável por ser um processo de molde fechado, possibilitou a fabricação de produtos com elevado teor de fibra e boas propriedades mecânicas.

  • CRISTIANE GOMES MORAES
  • DESENVOLVIMENTO DE PROCESSO DE SÍNTESE DA ZEÓLITA A UTILIZANDO O CAULIM DA AMAZÔNIA E APLICAÇÃO NA ADSORÇÃO DE CU +2

  • Data: 22/08/2014
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  • Em todo mundo milhões de toneladas de resíduos inorgânicos são produzidos a cada dia
    em atividades de mineração e beneficiamento mineral. Estes resíduos são armazenados
    em bacias de sedimentação ou descartados em aterros e, muito comumente são jogados
    diretamente no meio ambiente, sem qualquer processo de tratamento. Todavia,
    alternativas de reciclagem e/ou reutilização devem ser investigadas e, sempre que
    possível. Este trabalho mostra estudos realizados, visando a reutilização do resíduo de
    caulim da Amazônia, proveniente de uma empresa de beneficiamento de caulim para
    cobertura de papel. Para a síntese da zeólita A nos processos hidrotérmicos estático e
    dinâmico, utilizou-se como o fonte de silício e alumínio o resíduo de caulim, que passou
    pelo processo de calcinação em mufla a 600°C para obtenção do metacaulim; e como
    fonte de sódio optou-se por uma solução de hidróxido de sódio 5M. No processo
    estático utilizou-se autoclaves de aço inoxidável, em estufa a temperatura de 110°C,
    utilizando 1,75g de metacaulim, variando os tempos de síntese e a massa de hidróxido
    de sódio e no processo dinâmico utilizou-se 100g de metacaulim, massa de 34,5g de
    hidróxido de sódio; a temperatura de 95°C em sistema de agitação, variando os tempos
    de síntese, a fim de determinar as condições ideais na síntese da zeólita A no processo.
    Os materiais de partidas e os produtos zeolíticos obtidos nas sínteses foram
    caracterizados através: difração de raios-X (DRX), microscopia eletrônica de varredura
    (MEV), análise térmica diferencial e termogravimétrica (ATG/TG), fluorescência de
    raios-X (FRX) e análise granulométrica. Há possibilidade do aumento de escala, pois
    obteve zeólita A, no processo dinâmico no tempo de 30 min. Os dados dos ensaios de
    adsorção determinados, pela técnica iodométrica de Cobre em ligas metálicas e minerais
    e ajustados pelos modelos de Langmuir e Freundlich sugerem que os materiais
    zeolíticos estático e dinâmico apresentam boa capacidade adsortiva atingido eficiência
    de 95% para concentrações na faixa de 50 a 100 mg/L, demonstrando assim, que os
    referidos materiais são uma alternativa eficiente e de baixo custo quando utilizados para
    a remoção de metais pesados, no caso do cobre, no tratamento de efluentes industriais.

  • MATHEUS BRAGA FURTADO
  • PRODUÇÃO DE BIODIESEL A PARTIR DO PROCESSAMENTO DAS OLEAGINOSAS AMAZÔNICAS PLUKENETHIA POLYADENIA (COMPADRE-DO-AZEITE) E ONPHALEA DIANDRA (COMADRE-DO-AZEITE)

  • Data: 09/06/2014
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  • Analisa-se experimentalmente a produção de biodiesel a partir do processamento das oleaginosas amazônicas compadre-do-azeite (Plukenethia polyadenia) e comadre-do-azeite (Onphalea diandra), como uma alternativa potencialmente viável para compor  a matriz energética. Desde a Revolução Industrial no século XIX, a matriz energética mundial sempre foi baseada em combustíveis fósseis. Com a escassez desses combustíveis, a elevação de preços muito ocasionada com os constantes conflitos nas principais regiões produtoras, tem tornado as pesquisas em fontes renováveis cada vez mais atrativas. O estudo de novas fontes de óleos vegetais como alternativa energética é importante para o País, particularmente para os amazônicos; possibilitando estruturar cadeias produtivas de oleaginosas na região, gerando emprego no campo, efeitos distributivos na economia regional e, um vetor de desenvolvimento sustentável na Amazônia, sem agressão ao meio ambiente. A proposta deste trabalho é estudar duas espécies da família euphorbiaceae, as lianas Plukenethia polyadenia e Onphalea diandra, mais conhecidas como compadre-do-azeite e comadre-do-azeite respectivamente, produtoras de óleo; extrair e caracterizar os mesmos, sugerindo possíveis aplicações e utilizando-os para a produção de biodiesel através de uma transesterificação metílica, utilizando hidróxido de potássio como catalisador, tratando-se o processo com base em ensaios estatisticamente planejados. Verifica-se a influência das variáveis de entrada: concentração óleo/álcool, temperatura e concentração de catalisador na resposta rendimento em biodiesel, através da metodologia de superfície de resposta (RSM) empregando o planejamento de Box-Behenken. Visa-se dessa forma agregar valor a um rejeito da indústria de beneficiamento de caulim, utilizando zeólitas produzidas desse material como catalisador em substituição ao KOH, comparando as eficiências dos dois tratamentos. O planejamento de Box-Benhken se mostrou eficiente para otimizar a catálise homogênea dos biodieseis, concluindo-se que a concentração do catalisador foi a variável controladora do processo de produção dos biodieseis, e o aumento de sua concentração causa influência negativa e indesejável ao rendimento do produto. 

  • RAIMUNDA FIGUEIREDO DA SILVA MAIA
  • OBTENÇÃO E CARACTERIZAÇÃO DE LIGAS DE OURO APLICADAS AO SETOR JOALHEIRO NO ESTADO DO PARÁ

  • Data: 05/06/2014
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  • O ouro e suas diversas ligas tem maior aplicação como adorno em peças de joalheria, mas o ouro puro não apresenta dureza necessária para essa utilização. Por essa razão é geralmente endurecido com outros metais. Foram obtidas quatro (4) ligas de ouro, sendo (1) um intermetálico Au20%Al de cor violeta e três (3) de coloração usual na fabricação de joias (Au-25%Ag – verde claro, Au-12,5%Cu – vermelha Au-12,5%Ag-12,5%Cu – amarela). Propõe-se introduzir o uso do intermetálico e a melhoria na produção de ligas para setor joalheiro por meio da elaboração e caracterização das propriedades óticas, estruturais e mecânicas. Foram obtidas no Laboratório de Materiais da Faculdade de Engenharia Química da Universidade Federal do Pará (UFPA) e a liga Au-20%Al foi produzida nas oficinas de microprodutores do estado do Pará. As propriedades estruturais foram analisadas por meio de microscopia ótica (MO) e eletrônica de varredura (MEV). A partir das análises foi revelada estrutura celular dendrítica para as ligas Au-25%Ag e Au-12,5%Cu, estrutura dendrítica para a liga Au-12,5%Ag-12,5%Cu e estrutura celular para a liga Au-20%Al. As propriedades mecânicas foram obtidas através de ensaios de microdureza Vickers, verificando-se a maior dureza na liga Au-20%Al, intermetálico do tipo AX2. As propriedades óticas observadas por meio de ensaios de colorimetria, utilizando-se colorímetro, onde se evidenciaram espectros de luz visível dentro da faixa de cor violeta (Au-20%Al), amarelo esverdeada (Au-25%Ag), vermelho (Au-12,5%Cu), e amarelo (Au-12,5%Ag-12,5%Cu).

     

  • RONALDO NONATO FERREIRA MARQUES DE CARVALHO
  • RECICLAGEM DE RESIDUOS PARA PRODUÇÃO DE PLACAS CERAMICAS FABRICADAS COM ARGAMASSAS DE MATRIZ SÍLICO-ALUMINOSA DESTINADAS AO RESTAURO DE EDIFICAÇÕES HISTÓRICAS EM SUBSTITUIÇÃO A TAIPA E PRODUÇÃO DE PAINEIS DIVISORIOS
  • Data: 22/05/2014
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  • Este trabalho trata da concepção de argamassas que, conjugadas com trama de dutos em PVC, propiciam nova pespectiva para o restauro de edificações em taipa-de-mão no Estado do Pará, criando técnica pós-moderna e ecológica, na medida que propõe-se a produção de placas taipadas, utilizando-se predominantemente de materiais rejeitados da construção civil, além de Cinzas Volantes oriundos da queima de carvão mineral e da Cal hidratada. Com a produção de placas articuláveis é possível recuperar-se paredes historicamente construídas em taipa-de-mão, bem como executar-se painéis divisórios tanto em prédios históricos como contemporâneos. As placas em estrutura taipal, conjugadas com perfis de alumínio, não só adequam-se as ações de restauração como também propiciam a confecção de painéis, configurando-se como nova alternativa para construção de paredes em forma de divisórias. É bom frisar que o alvo ecológico deste estudo refere-se ao reaproveitamento de materiais que na atual conjuntura são desprezíveis e pouco utilizados. Visando desenvolver material argamássico, tendo como características a plasticidade, a elasticidade e a resistência mecânica a partir de resíduos industriais, foram necessários vários experimentos que proporcionaram diversas argamassas com traços de diferente composições. O desenvolvimento destes experimentos, nos quais misturas de rejeitos de construção civil, cinza volante e cal devidamente processados foram dosadas e após a confecção de corpos de prova, foram submetidas a ensaios de Absorção, Porosidade, Massa específica aparente e Resistência à compressão, resultou na seleção do composto mais adequado, em relação ao valores de referência segundo as Normas brasileiras.
  • EDUARDO DE SOUZA MAFRA
  • “ANÁLISE EXPERIMENTAL DA EXTRAÇÃO DO ÓLEO ESSENCIAL DE PUXURI [Licaria puchury-major (Mart.) Kosterm., Lauraceae.] POR ARRASTE COM VAPOR”

  • Data: 30/04/2014
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  • Analisa-se experimentalmente o processo de extração do óleo essencial de sementes e de partes
    aéreas de puxuri por arraste com vapor. O puxuri [Licaria puchury-major (Mart.) Kosterm.,
    Lauraceae], é uma espécie florestal da Amazônia com grande potencial para a indústria de bioprodutos
    (fármacos, cosméticos, alimentos e praguicida natural) devido à presença de safrol no
    seu óleo essencial. Realiza-se neste trabalho um estudo anatômico e de caracterização física e
    química das partes da planta utilizadas para a extração do óleo. Estuda-se a cinética da secagem
    de sementes, ramos finos e folhas de puxuri e quantifica-se a influência da secagem convectiva
    em leito fixo nos teores de safrol e no conteúdo de umidade final. Por meio de experimentos
    estatisticamente planejados, identificam-se os níveis das variáveis de processo: teor de umidade,
    tempo de extração e granulometria das amostras de sementes de puxuri, que otimizam simultaneamente
    as respostas: rendimento em óleo essencial e teor de safrol, seu componente majoritário,
    dentro do domínio experimental adotado e confiança de 90% ( = 0,10), no processo de
    extração do óleo essencial por arraste com vapor. Analisa-se quimicamente o óleo essencial de
    puxuri por CG-MS e identifica-se a composição química em termos de seus constituintes majoritários.
    Utilizando-se o método de aproximação gravimétrica estático com soluções concentradas,
    são obtidas isotermas de dessorção para sementes de puxuri em pó, a 15, 25 e 35ºC. Aos
    dados experimentais de equilíbrio higroscópico, ajusta-se muito bem o modelo de GAB, sendo
    estimados os calores de sorção líquidos e integrais, além dos teores de umidade de equilíbrio na
    monocamada e demais constantes da equação. Constata-se baixa toxicidade do óleo essencial de
    puxuri e que o resíduo sólido da extração pode ser utilizado como material saponificável para a
    produção de sabões transparentes a frio.

  • MARIANE FURTADO GONCALVES
  • REGIONALIZAÇÃO E ESTIMATIVA DE CHUVAS DO ESTADO DO PARÁ

  • Data: 25/04/2014
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  • Na região Amazônica, um dos fatores que impede o conhecimento mais
    abrangente dos recursos hídricos é a falta de dados hidrológicos (vazão e precipitação)
    das pequenas e médias bacias hidrográficas. Isto se dá principalmente em virtude
    dimensão da região, o que aumenta os custos de implantação e operacionalização da
    rede. Nesse contexto, o presente trabalho tem como objetivo o desenvolvimento de um
    modelo de regionalização e estimativa de chuvas para estado do Pará. Assim, foi
    aplicada uma metodologia para delimitação de regiões homogêneas de precipitação,
    através da análise de agrupamento, em seguida foi determinada a probabilidade de
    ocorrência de lâminas de chuva para região pluviometricamente homogênea obtida com
    a análise de agrupamento, através da aplicação de funções de probabilidade; e por
    último foram determinadas estimativas de lâminas de chuvas, utilizando-se modelos de
    regressão múltipla. Para todas as etapas, utilizaram-se valores precipitações médias
    anuais e mensais, de uma série histórica com 31 anos (período de 1960 - 1990), obtidos
    no site do Centro de Pesquisa Climática, Departamento de geografia, Universidade de
    Delaware, Newark, DE, E.U.A. Dentre os anos analisados, foram selecionados anos
    com ocorrência do fenômeno El Niño e La Niña. Utilizando-se o método hierárquico
    aglomerativo de Ward, tendo como medida de similaridade a distância euclidiana, para
    precipitações médias anuais e mensais, foram encontradas seis regiões homogêneas de
    precipitação, exceto para precipitações médias mensais para séries com ocorrência de El
    Niño e La Niña, que apresentaram quatro e cinco regiões homogêneas, respectivamente. 

    Após a definição das regiões homogêneas, modelos de probabilidades (Normal, Gumbel
    e Exponencial) foram ajustados para a determinação de lâminas de chuvas nas três
    sequências de séries históricas, sendo aplicado o teste Qui-quadrado para esta
    verificação. Após a etapa de calibração, para precipitações médias anuais, constatou-se
    que o modelo de distribuição Normal ajustou-se melhor a probabilidade de excedência
    observada; já para precipitações médias mensais o modelo de distribuição Gumbel
    obteve melhor aderência às frequências de excedência. Os modelos supracitados foram
    validados, utilizando as séries pluviométricas de 12 estações da Agência Nacional de
    Águas (ANA), consideradas como estações alvo. Nesta etapa, foi observado que para
    precipitação média anual, ocorreu aderência dos dados a todas as estações
    pluviométricas alvo, pois apresentaram resultados da aplicação do teste qui-quadrado
    inferior a 3,84 (para funções de distribuição normal). E também se constatou que para
    precipitação média mensal, houve aderência dos dados a todas as estações
    pluviométricas alvo. Para simulação de lâminas de precipitação, foram testados na
    calibração, modelos de Potência, segundo modelo de Potência e Linear através do
    método de regressão múltipla. Como critério de desempenho dos modelos, foi utilizado
    o erro relativo percentual. Para série histórica contendo todos os anos e séries com
    ocorrência de La Niña, o modelo que apresentou menor erro relativo percentual foi o
    Linear. Já para séries com ocorrência de El Niño, o modelo de Potência apresentou
    menores erros. Assim como, para os modelos probabilísticos, os resultados da
    calibração dos modelos de regressão múltipla, foram validados com a utilização de
    estações pluviométricas da ANA. Na etapa de validação para séries contendo todos os
    anos os erros percentuais variaram de 0,2-39,2%, já quando utilizado em anos de El
    Niño houve um aumento do erro, variando 1,9-54,8%, e em anos de La Niña de 8,555,9%.
    Apesar de algumas estimativas terem erros consideráveis, acima de 50%, os
    resultados obtidos, de forma geral, demonstraram que a metodologia pode ser uma boa
    opção como ferramenta numérica para regionalização e estimativa de chuvas. Os
    resultados da aplicação dessa metodologia são importantes para um melhor
    entendimento do regime pluviométrico do Estado do Pará e da Amazônia, podendo
    servir como ferramenta para um melhor planejamento e gestão de recursos hídricos da
    região.

  • SERGIO ARUANA ELARRAT CANTO
  • UMA NOVA PROPOSTA DE MÉTODO DE AVALIAÇÃO DE FOGÃO À BIOMASSA

  • Data: 14/03/2014
  • Mostrar Resumo
  • Esta pesquisa apresenta o Método de Avaliação Global de Fogões à Biomassa -
    (MAGOF) que inova por considerar um fogão a biomassa um equipamento de uso
    doméstico, portanto um produto, diferentemente dos protocolos de avaliação conhecidos,
    que priorizam os aspectos energéticos. O MAGOF determina o índice de Desempenho
    Global empregando 72 Requisitos de Qualidade referentes ao ciclo de vida do produto,
    distribuídos por afinidade entre 5 Atributos que irão indicar os Desempenhos Específicos
    de Projeto, Ambiental, de Funcionalidade, Energético, onde está inserido o conhecido
    Water Boiling Test (WBT), e o desempenho Econômico. Estas particularidades
    inovadoras oferecem informações relevantes para projetistas, pesquisadores, fabricantes,
    usuários, consumidores, investidores, instituições governamentais reguladoras ou
    fiscalizadoras e demais atores. Estas informações geradas favorecem o processo
    decisório, a inovação tecnológica, o melhoramento dos fogões, a saúde e segurança dos
    usuários, a preservação ambiental e reflete na economia. O MAGOF tem relevância de
    interesse mundial por ser uma ferramenta alinhada aos esforços mundiais na busca de
    soluções para os abrangentes problemas decorrentes das inadequações dos fogões a
    biomassa, já que cerca de 2,5 bilhões de pessoas usam lenha ou carvão para cozinhar em
    todos os continentes, e a Organização Mundial da Saúde (OMS) constatou que cerca de
    1,5 milhão de pessoas morrem anualmente vítimas de doenças respiratórias causadas
    principalmente por fumaça emitidas por fogões à biomassa. A pesquisa também traz uma
    aplicação do MAGOF num fogão produzido pela empresa Ecofogão e um fogão artesanal
    amazônico e compara os respectivos desempenhos

2013
Descrição
  • KLEBER BITTENCOURT OLIVEIRA
  • ESTUDO DA EXTRAÇÃO DE COBRE UTILIZANDO CONTACTORES COM MEMBRANAS COMO ALTERNATIVA AO
    PROCESSO CONVENCIONAL DE EXTRAÇÃO POR SOLVENTE

  • Data: 27/12/2013
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  • Este trabalho estudou a extração de cobre utilizando contactores com membranas como
    alternativa ao processo SX convencional. Foram investigados os parâmetros relevantes
    do processo como, tipo e concentração de extratante, solvente, solução de strip, tempo e
    pH de operação. Além disso, foi desenvolvido um modelo matemático a partir de um
    sistema de equações diferenciais parciais resultantes do balanço de massa no sistema de
    contactor com membranas, utilizando como metodologia de solução a Técnica das
    Integrais Acopladas (CIEA). Os estudos experimentais realizados neste trabalho
    mostraram que uso de contactores com membranas na extração líquido-líquido de cobre
    é uma tecnologia promissora e viável, tendo potencial para substituir o método de
    extração por solvente por contato direto adotado atualmente obtendo-se 100% de
    extração de cobre utilizando LIX 84I 20% (v/v) como extratante, querosene como
    solvente, H2SO4 como solução de strip, em um tempo de operação de 80 minutos. Os
    resultados obtidos através da modelagem matemática e simulação do problema físico
    analisado neste trabalho foram comparados com os resultados experimentais e mostramse
    satisfatórios, demonstrando a capacidade da CIEA em tratar problemas de
    transferência de massa em sistema de contactor com membranas.

  • DYENNY ELLEN LIMA LHAMAS
  • ESTUDO DO PROCESSO DE CRAQUEAMENTO TERMOCATALÍTICO DO ÓLEO DE PALMA (Elaeis guineensis) E DO ÓLEO DE BURITI (Mauritia flexuosa L.) PARA PRODUÇÃO DE BIOCOMBUSTÍVEL
  • Data: 19/12/2013
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  • O presente trabalho visa estudar o processo de craqueamento termocatalítico dos óleos de palma e de buriti para produção de biocombustíveis. No desenvolvimento deste estudo foram realizados testes com óleo de buriti nas escalas de bancada e semi-piloto e experimentos com óleo de palma nas escalas de bancada, semi-piloto e piloto. Inicialmente, foram realizados testes com catalisadores ácidos (sílica dopada com ácido fosfórico e HZSM-5) e carbonato de cálcio (CaCO3) na escala de bancada utilizando óleo de buriti. Os resultados mostraram que o catalisador HZSM-5 apresentou maior rendimento em produto líquido, porém, com o carbonato de cálcio obteve-se um produto líquido demelhor qualidade mostrada pelo baixo índice de acidez. Desta forma,optou-se pelo uso do catalisador carbonato de cálcio na maioria dos experimentos,testando apenas o óxido de cálcio na escala semi-piloto. Nesta escala houve redução dos parâmetros de processo e do índice de acidez do produto líquido quando comparado com os produtos gerados no craqueamento térmico, mostrando eficiência dos catalisadores básicos usados no processo. Na escala piloto, observou-se que os rendimentos em produtos líquidos aumentaram com o aumento da temperatura de operação e da porcentagem do catalisador básico. Parte dos produtos obtidos nesta escala foi submetida à destilação em bancada, visando obter frações correspondentes às faixas da gasolina, querosene, diesel leve e diesel pesado. Os resultados das análises cromatográficas dos produtos líquidos e destas frações destiladas confirmaram a presença de hidrocarbonetos correspondentes aos principais frações de petróleo.
  • ANTONIO DE LIMA MESQUITA
  • ESTUDOS DE PROCESSOS DE EXTRAÇÃO E CARACTERIZAÇÃO DE FIBRAS DO FRUTO DO AÇAÍ (Euterpe oleracea MART.) DA AMAZÔNIA PARA PRODUÇÃO DE ECOPAINEL DE PARTÍCULAS HOMOGÊNEAS DE MÉDIA DENSIDADE.

  • Data: 06/12/2013
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  • O tecido fibroso do fruto do açaí (Euterpe oleracea Mart.) é descartado cerca de 1.200 t/dia, na Região Metropolitana de Belém (PA) após a produção de suco. Esse resíduo agroindustrial com pouca frequência é utilizado em caldeiras como fonte de cogeração de energia. Visando o aproveitamento da fibra do fruto, o objetivo deste trabalho foi estudar processos de extração das fibras e tratamento por meio da maceração biológica: espontânea e induzida e mercerização química: com NaOH, com e sem autoclave. Para tanto, foi realizada caracterização anatômica, química, física e mecânica das fibras de açaí com o intuito de utilizálas para o desenvolvimento de novos materiais compósitos alternativos para indústria da construção civil. Para obtenção das fibras foram utilizados processos manuais e mecânicos. Para maceração biológica espontânea foi utilizada a água
    do Rio Guamá (AG) e a água da Cosanpa (AC) e na condição experimental biológica induzida foi utilizada a raspa da mandioca (MD). As concentrações de água e de raspa de mandioca foram 2%, 4% e 6% em massa. O tratamento químico alcalino foi realizado de duas formas: (1) utilizou-se uma solução alcalina de NAOH com as seguintes concentrações em massa: 0,5%, 1% e 2%; (2) parte das fibras tratadas foram colocadas no autoclave. Para o estudo anatômico o tecido fibroso foi macerado e analisado em microscopia ótica e eletrônica de
    varredura, para caracterizar os constituintes celulares. Para caracterização mecânica foi realizado o ensaio de tração axial das fibras de açaí, para a obtenção da resistência à tração máxima. Na caracterização química das fibras foram realizadas análises químicas do conteúdo total de lignina, celulose e hemicelulose.
    Após os tratamentos de maceração biológica e alcalina foram analisados estatisticamente os resultados dos ensaios mecânicos para escolher o melhor tratamento para as fibras que foram usadas na produção ecopainéis de partículas homogêneas aglomeradas com resina poliuretana bicomponente a base de óleo
    de mamona. Após a fabricação dos ecopainéis com a resina poliuretana foi  realizada a caracterização físico-mecânica e microestrutural que compreendeu a determinação das propriedades físicas: densidade aparente-(Dap), inchamento em espessura (IE) e absorção de água (Abs); e propriedades mecânicas: módulo de elasticidade (MOE), módulo de ruptura (MOR), resistência à adesão interna (RAI) e arrancamento de parafuso na superfície (RAsup) e no topo (RAtop). Os resultados das caraterização das fibras indicaram a grande quantidade de esclereídes e fibrotraqueídes constituídos de numerosos apêndices presentes nas superfícies das fibras celulósicas (feixes vasculares) os quais são responsáveis pela resistência mecânica das fibras. As fibras apresentaram 30% de lignina, 44 %- 46% de celulose e 18% -20% de hemicelulose. As fibras do processo de mercerização alcalina NaOH com 0,5% em massa e autoclave foi selecionada para a fabricação dos ecopainéis. Os resultados das propriedades físicas, apresentaram ecopainéis de partículas homogêneas classificados como de média densidade na faixa de 713 a 745 kg/m3.. Os valores médios dos ecopainéis com fibras tratadas de inchamento em espessura foram em média 36% e 40% inferiores, após 2 e 24 h, respectivamente, dos ecopainéis com as fibra não tratadas. As mesmas reduções de 35% e 17% nos valores de absorção de água, após 2 h e 24 h, respectivamente, foram observadas. As propriedades mecânicas dos ecopainéis com fibras tratadas apresentaram valores superiores em 31% no MOR, 89% no RAI e 54% no RAtop, comparado com os ecopainéis referência (fibras sem tratamento). Tais resultados sugerem a potencialidade da fibra do açaí, com tratamento alcalino e submetido a autoclave, como matéria prima na produção de ecopainéis homogêneos particulados de media densidade (MDP) para uso comercial na indústria da construção civil e moveleira.

  • SILVIO ALEX PEREIRA DA MOTA
  • CRAQUEAMENTO TERMO-CATALÍTICO DE ÓLEOS VEGETAIS EM DIFERENTES ESCALAS DE PRODUÇÃO
  • Data: 06/09/2013
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  • Neste trabalho, realizou-se o estudo da obtenção de biocombustíveis a partir do processo de craqueamento em diferentes escalas de produção. Para o desenvolvimento deste estudo utilizou-se três unidades de craqueamento, com capacidades de 125 ml/batelada, de 2.000 ml/batelada e outra unidade de 138.000 ml/batelada. Parte dos produtos obtidos foi destilada em escala de bancada com uma coluna do tipo vigreux e em escala piloto com uma coluna do tipo empacotamento. Nas reações de craqueamento térmico e termocatalítico verificou-se a eficiência da utilização de catalisadores, avaliou-se diferentes tipos de catalisadores (Na2CO3, CaCO3, HZSM-5, SiO2/H3PO4, Lama Vermelha), além de diferentes tipos de matérias primas (óleo de palma, buriti, andiroba, girassol, soja residual e sebo bovino). Os resultados obtidos em escala de bancada mostram que, o catalisador HZSM-5 obteve melhor rendimento 79 % porém, o biocombustível obtido com Na2CO3 apresentou melhor qualidade físico-química. Na escala semi-piloto, a reação com carbonato de sódio e óleo de amdiroba, obtiveram melhores resultados. Quanto ao craqueamento em escala piloto seguido da etapa de destilação, onde se utilizou óleo de palma e Na2CO3 como catalisador, os produtos obtidos foram submetidos a analise de GCMs, tendo como resultado à confirmação da obtenção hidrocarbonetos na faixa da gasolina, do querosene e do diesel, apresentando compostos parafínicos, ólefínicos, naftêncos e traços de aromáricos em suas composições, variando a concentração destes para cada tipo de biocombustível produzido.
  • LUIS CARLOS ALVES VENANCIO
  • DESENVOLVIMENTO DE UNIDADE PILOTO DE TRANSFERÊNCIA DE MASSA GÁS/LÍQUIDO: REDUÇÃO DA REATIVIDADE DO RESÍDUO DA INDÚSTRIA DE ALUMINA ATRAVÉS DA REAÇÃO COM GASES DE COMBUSTÃO
  • Data: 06/02/2013
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  • O refino de bauxita utilizando o processo Bayer produz de 0,7 a 2,0 t do resíduo conhecido como lama vermelha e cerca de 1,0 t de CO2 para cada tonelada de alumina produzida. O resíduo de bauxita apesar de não ser particularmente tóxico, apresenta riscos ao meio ambiente devido ao grande volume e a sua reatividade. De acordo com a tecnologia mais recente tem parte da umidade removida e é empilhado em depósitos impermeáveis especialmente construídos. Mais de 95% do resíduo de bauxita que já foi produzido no mundo (2,6 Bt até 2007) foi descartada, principalmente em depósitos em terra. Esta tese mostra o projeto, a construção e a operação de uma unidade de transferência de massa gás líquido em escala piloto com o objetivo de testar a redução da reatividade do resíduo de bauxita através da reação com gás de combustão. Como ganho adicional há a redução da emissão de dióxido de carbono e dióxido de enxofre. Esta unidade, composta por três reatores, foi projetada de modo a consumir o mínimo de energia, utilizar os efluentes da maneira mais eficiente possível e minimizar o custo de investimento. Foram realizados 25 experimentos com duração de 80 a 520 minutos cada um. Os gases foram analisados com o uso de sensores eletroquímicos e infravermelho não dispersivo na entrada e saída. O pH foi mensurado durante e após a reação de modo a avaliar os resultados curto e longo prazo bem como a estabilidade das reações. Foi demonstrada a viabilidade de reagir o resíduo de bauxita com os gases provenientes da combustão de fontes fósseis da própria refinaria sem processamento prévio com o pH de estabilização atingindo 10,5.
2012
Descrição
  • ANDRE LUIS DE LIMA SARAIVA
  • Análise dos Impactos da Dinâmica de Sólidos e de Nutrientes na Qualidade da Água de Ambiente Lêntico Utilizado no Abastecimento de Comunidades Amazônicas"
  • Data: 14/08/2012
  • Mostrar Resumo
  • Os mananciais do Utinga, formados pelos lagos Bolonha e Água Preta, estão contidos em uma Área de Proteção Ambiental - APA e são utilizados pela Companhia de Saneamento do Pará – COSANPA, para o abastecimento da população da Região Metropolitana de Belém - RMB. Esses mananciais são constituídos pelo rio Guamá, onde a água é captada e enviada por recalque ao lago Água Preta, que por um canal artificial com escoamento por gravidade, alimenta o lago Bolonha, e é bombeado para a Estação de Tratamento de Água - ETA. Os principais problemas de poluição/contaminação desses mananciais surgiram com o avanço urbanístico desordenado, que ocasionam o lançamento indevido de esgoto e resíduos sólidos dos bairros, favelas e conjuntos residenciais próximos às principais nascentes. O presente estudo assume fundamental importância no monitoramento e conhecimento da qualidade da água dos Lagos Bolonha e Água Preta visando prevenir e/ou corrigir processos de degradação, desenvolvendo ferramentas de avaliação da qualidade da água de ambiente lacustre, com base na sedimentação de sólidos e na ciclagem de nutrientes, tendo como finalidade a proteção do recurso hídrico e sua utilização no abastecimento público de água potável.
  • MARIA DE FATIMA MENDES LEAL
  • PROPOSTA DE METODOLOGIA PARA AVALIAÇÃO DO GRAU DE SUSTENTABILIDADE UTILIZANDO LÓGICA FUZZY: APLICAÇÃO NA INDÚSTRIA MADEIREIRA
  • Data: 22/05/2012
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  • As necessidades econômicas das empresas aliadas à necessidade de preservação do meio ambiente requerem um desenvolvimento de suas atividades de uma maneira que seja ambientalmente responsável e, consequentemente, com o uso adequado dos recursos naturais. A economia do Estado do Pará tem por base a agricultura, a pecuária e o extrativismo mineral e vegetal, sendo este último representado, principalmente, pela madeira. Certamente contribuirá para o uso sustentável desse recurso florestal, uma avaliação que quantifique os subsistemas ambiental, econômico e social, que são a base da sustentabilidade. Estudando o segmento de beneficiamento e exportação da madeira foi aplicada a lógica fuzzy em uma proposta metodológica de determinação do grau de sustentabilidade que neste estudo pode variar em uma escala de 0 a 10, quantificando não só a condição da sustentabilidade em si, mas também indicando quais subsistemas ou componentes que precisam ser melhorados. A determinação de políticas públicas para o setor madeireiro poderá ser realizada utilizando a mesma metodologia, desde que sejam feitos os ajustes legais necessários.
  • EDILSON MARQUES MAGALHAES
  • ESTUDO DA EXTRAÇÃO DE COMPOSTOS DE FERRO DA LAMA VERMELHA VISANDO A CONCENTRAÇÃO E/OU EXTRAÇÃO DE COMPOSTOS DE TITÂNIO

  • Data: 12/04/2012
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  • As principais preocupações com relação à geração de resíduos estão voltadas para os efeitos que estes materiais podem ter sobre a saúde humana e sobre o meio ambiente, uma vez que os resíduos perigosos produzidos pelas indústrias precisam particularmente de atenção e cuidado, pois quando incorretamente gerenciados, tornam-se uma grave ameaça ao meio ambiente. Neste contexto, este trabalho mostra os estudos realizados para a reciclagem da lama vermelha, como matéria-prima para a obtenção de compostos de titânio. O estudo abrange três rotas hidrometalúrgicas: lama vermelha calcinada a 900°C (LV900), lama vermelha sem tratamento térmico (LV-STT) e lama vermelha sinterizada em atmosfera redutora (LV1300). Os experimentos de lixiviação foram realizados com valores de temperaturas de 60, 80 e 90°C e concentração de ácido sulfúrico de 20 e 30%. Junto com o estudo de lixiviação foi realizada a modelagem matemática do processo de lixiviação. Os estudos realizados neste trabalho mostram que a lama vermelha pode ser aplicada como fonte de matéria-prima alternativa para a concentração e posterior recuperação de compostos de titânio. A modelagem cinética dos dados das curvas de extração em função do tempo, o modelo matemático desenvolvido no pressente trabalho, mostra que, matematicamente, a reação química é a etapa que descreve esses ensaios de lixiviação. O modelo desenvolvido também possibilitou a obtenção de parâmetros cinéticos, tais como, energia de ativação e velocidades das reações químicas do processo de lixiviação. 

  • REIMAR DE OLIVEIRA LOURENCO
  • ANÁLISE EXPERIMENTAL E NUMÉRICA DA FLUIDIZAÇÃO PARA APLICAÇÕES INDUSTRIAIS
  • Data: 26/03/2012
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  • Os leitos fluidizados gás-sólido possuem grande importância na indústria de processamento, em função de apresentar um bom efeito de mistura entre as fases, além de altas taxas de transferência de calor e massa, necessitando para isso baixo consumo de energia. Alguns exemplos típicos de aplicações industriais desse equipamento podem ser encontrados em processos que envolvem reações catalíticas, regeneração catalítica, ou ainda a combustão e gaseificação de carvão. O entendimento do comportamento fluidodinâmico deste equipamento é de fundamental importância para que o leito fluidizado possa ser adaptado a novas condições de uso. A literatura reporta diversos estudos com leito fluidizado, relatando variadas contribuições já incorporadas ao conhecimento da operação do mesmo. A ferramenta de CFD (Computational Fluid Dynamics) tem se mostrado uma boa alternativa para entendimento da operação deste equipamento. A utilização do modelo Euleriano granular multifásico juntamente com equações de conservação da massa, energia e movimento, para cada uma das fases presentes, tem gerado êxito quando aplicada a leitos fluidizados. De forma geral, este trabalho teve por objetivo estudar o comportamento do escoamento fluidodinâmico de esferas de vidro e alumina em um leito fluidizado convencional do tipo gás-sólido, variando os modelos de arraste de Gidaspow, Syamlal-O’Brien e Wen-Yu, bem como os modelos de turbulência K- e RSM. De forma mais específica, o trabalho buscou avaliar o comportamento fluidodinâmico das partículas no equipamento, através do monitoramento dos parâmetros fluidodinâmicos mais importantes, dentre os quais podemos destacar a velocidade de mínima fluidização do mesmo, a queda de pressão do equipamento na mínima fluidização, sua porosidade e a expansão do leito de partículas, também na mínima fluidização. Os testes experimentais foram comparados com simulações numéricas utilizando a ferramenta de CFD, onde se observou boa concordância dos resultados simulados frente aos resultados experimentais.
  • ROMULO CORREA LIMA
  • DESENVOLVIMENTO DE UM MODELO VIA MEF PARA ANÁLISE DA DISPERSÃO DE POLUENTES EM RIOS, LAGOS E ESTUÁRIOS
  • Data: 21/03/2012
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  • Água doce de boa qualidade é um pré-requisito para o desenvolvimento social e econômico de uma dada região. Paradoxalmente, este mesmo desenvolvimento é, normalmente, responsável pela poluição de suas fontes hídricas, através de despejo de resíduos domésticos ou industriais sem tratamento, ou através de atividades agrícolas. Desta forma, o monitoramento e o gerenciamento destas fontes são de extrema importância para o bem estar da população. Entre as possíveis ferramentas para auxiliar este gerenciamento, encontra-se a simulação computacional de transporte de poluentes nos meios hídricos. Neste contexto, o presente trabalho apresenta um procedimento para a solução computacional da equação de advecção-difusão-reação em 2D, a qual é a base para todos os modelos de transporte de massa. O processo consiste na união entre os métodos de elementos finitos e de diferenças finitas na discretização das componentes espaciais e temporal, respectivamente. Esta metodologia foi avaliada em testes com dados sintéticos e também reais. No primeiro considerou-se o caso de transporte de massa por advecção pura para certificar a estabilidade nos casos em que as formulações clássicas falham. No segundo simulou-se o transporte de um poluente hipotético em um trecho de rio e obtiveram-se os efeitos próprios do arraste devido à advecção e o espalhamento devido à difusão. O último teste examinou o transporte de fósforo total no lago Água Preta a partir das águas bombeadas do rio Guamá e de fontes pontuais localizadas nas margens deste reservatório. O resultado da simulação mostrou a potencialidade do algoritmo em tratar casos mais próximos da realidade.
  • INALDO CLAUDIO MARTINS DA SILVA
  • EXTRAÇÃO DO ÓLEO DE Cyperus articulatus L var. articulatus (priprioca) USANDO O DIÓXIDO DE CARBONO SUPERCRÍTICO.
  • Data: 06/03/2012
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  • O Objetivo principal do presente trabalho é evidenciar os mecanismos de transferência de massa da extração com dióxido de carbono em condições supercríticas na região monofásica e multifásica de um sistema pseudo-binário: (1) dióxido de carbono e (2) extrato de priprioca. Sabe-se a priori, que o conhecimento do comportamento de fases de sistemas contendo dióxido de carbono e óleo essencial é um parâmetro importante para definir as condições operacionais de temperatura e pressão na extração supercrítica. No entanto, raros são os trabalhos que se utilizam dessas informações, pois é mais comum extrair o óleo essencial usando o dióxido de carbono, a partir de experiências prévias, nas quais caracterizam-o quimicamente, e finalmente mede-se as condições de transição de fases do sistema binário (1) dióxido de carbono e (2) óleo essencial. Utilizando o conhecimento do comportamento de transição de fases do sistema pseudo-binário (1) dióxido de carbono e (2) priprioca medido por Moura et al. (2009) foram realizadas várias extrações com dióxido de carbono supercrítico nas regiões monofásica e multifásica. Além disso, foi realizado a caracterização química dos compostos químicos presente no óleo para todas as condições de extração supercrítica, bem como a quantificação da atividade anti-oxidante, atividade anti-fúngica, atividade antibacteriana. Foi também desenvolvida uma modelagem matemática das cinéticas de extração. As equações diferenciais parciais do problema em questão foram resolvidas utilizando-se a Técnica da Transformada Integral Generalizada (GITT).
  • MARCOS AUGUSTO EGER DA CUNHA
  • ADSORÇÃO E DESSORÇÃO SUPERCRÍTICA DE CAROTENOS E ANTIOXIDANTES DO ÓLEO DE BURITI (Mauritia flexuosa, Mart)EM LEITO DE γ-ALUMINA
  • Data: 05/03/2012
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  • Neste trabalho foi investigado o enriquecimento de antioxidantes do óleo de buriti (Mauritia flexuosa, Mart.) pelo processo de adsorção supercrítica. A adsorção foi realizada experimentalmente pelo método da análise frontal em colunas empacotada com -alumina a 15, 20 e 25 MPa, 333 K, e vazão de solvente de QCO2 = 10,6 L/min, utilizando uma montagem de colunas duplas de 81 cm3, testado e aprovado para ser usado como uma célula de adsorção. O óleo de buriti foi físico-quimicamente caracterizado de acordo com métodos oficiais da AOCS e mostrou-se compatível com os dados relatados na literatura. A composição em termos de ésteres metílicos foi determinada por cromatografia gasosa (GC) e a atividade anti-oxidante segundo o método de captura de radicais livres (DPPH). O adsorvente foi caracterizado por fluorescência e difração de raios X, determinando a distribuição de tamanho de partículas, porosidade e área específica por BET. A cada experimento, um balanço material era realizada na coluna de adsorção para calcular a massa das espécies adsorvidas em -alumina no processo de adsorção supercrítico. A influência da pressão sobre a adsorção supercrítica foi investigada através da análise do comportamento das isotermas. A isoterma de Langmuir foi usada para modelar os dados experimentais de adsorção. Os resultados experimentais mostram um aumento da capacidade adsorvente com pressões mais elevadas, mostrando um máximo de 90,9 ± 8,6 mg de óleo/g -alumina, a 25 MPa. A adsorção supercrítica de óleo de buriti em -alumina utilizando dióxido de carbono como solvente parece é método alternativo para extração de antioxidantes incluindo os carotenos.
  • YVELYNE BIANCA IUNES SANTOS
  •  

    DESENVOLVIMENTO DE SISTEMA COMPUTACIONAL PARA
    AVALIAÇÃO DE LODO DE ESGOTO SANITÁRIO COMO
    BIOMASSA NA GERAÇÃO DE ENERGIA

    DESENVOLVIMENTO DE SISTEMA COMPUTACIONAL PARA AVALIAÇÃO DE LODO DE ESGOTO SANITÁRIO COMO BIOMASSA NA GERAÇÃO DE ENERGIA

  • Data: 06/02/2012
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  •  

    Desenvolvimento de sistema computacional para avaliação de lodo de esgoto sanitário como biomassa na geração de energia em processos de combustão, considerando normas técnicas e ambientais brasileiras. No sistema foram criadas e implementadas classes para avaliação do potencial energético do lodo e considerados limites estabelecidos nas normas NBR 10004/04, NBR 10004/87 e Resolução nº 316/2002 do CONAMA para impactos ambientais adversos, danos ou riscos à saúde pública, identificando a viabilidade de aplicação desse resíduo como biomassa na geração de energia em processos de combustão. O sistema foi desenvolvido com padrão de arquitetura de software Model-View-Controller (MVC), com método representado por regras de lógica, tendo como dados de entrada os resultados de determinações laboratoriais de amostras de lodo de esgoto, processamento em testes e encadeamentos lógicos das regras e relatórios para possibilitar a tomada de decisão do usuário. Para a validação do sistema foram utilizados resultados de trabalhos técnicos de aplicação de lodo de esgoto como biomassa na geração de energia em escala experimental, sendo constatado como adequados os parâmetros adotados no sistema para avaliar o potencial energético do lodo amostrado, a toxicidade e a poluição atmosférica; que as mensagens de alerta e explicativas foram claramente emitidas; que o encadeamento lógico das regras foi executado progressivamente; e que os valores obtidos no sistema foram compatíveis com os dos trabalhos utilizados para validação. Finalizando, foi concluído que o sistema desenvolvido pode ser aplicado para agilizar a tomada de decisão, especialmente em estações de tratamento de esgoto com grande volume de lodo.
    Pal

    Desenvolvimento de sistema computacional para avaliação de lodo de esgoto sanitário como biomassa na geração de energia em processos de combustão, considerando normas técnicas e ambientais brasileiras. No sistema foram criadas e implementadas classes para avaliação do potencial energético do lodo e considerados limites estabelecidos nas normas NBR 10004/04, NBR 10004/87 e Resolução nº 316/2002 do CONAMA para impactos ambientais adversos, danos ou riscos à saúde pública, identificando a viabilidade de aplicação desse resíduo como biomassa na geração de energia em processos de combustão. O sistema foi desenvolvido com padrão de arquitetura de software Model-View-Controller (MVC), com método representado por regras de lógica, tendo como dados de entrada os resultados de determinações laboratoriais de amostras de lodo de esgoto, processamento em testes e encadeamentos lógicos das regras e relatórios para possibilitar a tomada de decisão do usuário. Para a validação do sistema foram utilizados resultados de trabalhos técnicos de aplicação de lodo de esgoto como biomassa na geração de energia em escala experimental, sendo constatado como adequados os parâmetros adotados no sistema para avaliar o potencial energético do lodo amostrado, a toxicidade e a poluição atmosférica; que as mensagens de alerta e explicativas foram claramente emitidas; que o encadeamento lógico das regras foi executado progressivamente; e que os valores obtidos no sistema foram compatíveis com os dos trabalhos utilizados para validação. Finalizando, foi concluído que o sistema desenvolvido pode ser aplicado para agilizar a tomada de decisão, especialmente em estações de tratamento de esgoto com grande volume de lodo.

2011
Descrição
  • PAULO DOUGLAS SANTOS DE VASCONCELOS
  • TRANSPORTE PNEUMÁTICO FLUIDIZADO ESTUDOS DE CASOS APLICADOS À INDÚSTRIA DO ALUMÍNIO PRIMÁRIO
  • Data: 05/08/2011
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  • Este trabalho é uma contribuição à ciência e à aplicação da tecnologia desenvolvida sobre leito e transporte fluidizado de materiais particulados usados nos processos industriais. No caso de leitos fluidizados desenvolveu-se uma equação semi-empírica para predição da velocidade mínima de fluidização da alumina fluoretada, pó de crosta e outros materiais particulados usados nos processos industriais com resultados bastantes satisfatórios comparados com os resultados experimentais em relação às equações disponíveis na literatura. Estudou-se também o comportamento dos ângulos de repouso e de fricção interno interpartículas propondo-se equações constitutivas para esses ângulos para alumina fluoretada como função da velocidade superficial de fluidização. Em uma segunda etapa propõem-se uma equação para predição da capacidade de transporte de calhas e tubos fluidizados com resultados de boa qualidade em relação aos experimentos realizados nos tubos fluidizados. Este tubo fluidizado por sua concepção pode operar em ângulos ascendentes em relação ao plano horizontal sendo uma contribuição tecnológica desta tese para diminuição da taxa kWh/ton de material particulado manuseados nos processos industriais.
  • LUIZ MOREIRA GOMES
  • "CONTRIBUIÇÃO À ANÁLISE DO TRANSPORTE PNEUMÁTICO EM FASE DILUÍDA"
  • Data: 04/08/2011
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  • Este trabalho é uma contribuição à análise do transporte pneumático em fase diluída. Trata do estudo dos parâmetros chave relacionado ao transporte de partículas sólidas por uma corrente gasosa em tubulações horizontais e verticais. Esses parâmetros são as velocidades críticas de transporte e a queda de pressão na tubulação. Assim, é feita a análise das principais correlações existentes na literatura voltadas para a previsão de tais velocidades críticas e, então, propostas para uso as mais confiáveis. Neste sentido, também foi desenvolvida uma equação para a previsão da velocidade de captura de partículas no fundo de uma tubulação horizontal. Em seguida foi analisado o comportamento da queda de pressão em função das propriedades das partículas sólidas e do sistema com o uso de dois softwares, sendo que um deles não considera em sua formulação a influência da zona de aceleração na queda de pressão. Assim, foi possível entender qual a contribuição do comprimento de aceleração na queda de pressão total e qual a faixa de aplicabilidade de cada um desses softwares. Foi feita ainda a análise da sensibilidade da porosidade inicial na queda de pressão na tubulação em função de parâmetros tais como a vazão mássica dos sólidos, o comprimento da tubulação, a massa específica das partículas sólidas e o diâmetro da tubulação.
2010
Descrição
  • SIMONE DE AVIZ CARDOSO
  • "A técnica da transformada integral na modelagem e simulação de processos de separação de metais por membranas difusivas poliméricas"
  • Orientador : JOAO NAZARENO NONATO QUARESMA
  • Data: 26/11/2010

  • JOSE ANTONIO DA SILVA SOUZA
  • "ESTUDO E AVALIAÇÃO DO USO DE RESÍDUOS DO PROCESSO BAYER COMO MATÉRIA-PRIMA NA PRODUÇÃO DE AGREGADOS SINTÉTICOS PARA A CONSTRUÇÃO CIVIL"
  • Orientador : JOAO NAZARENO NONATO QUARESMA
  • Data: 26/03/2010

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