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ANDERSON ROCHA AMARAL
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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
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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).
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GABRIELLE DOS ANJOS CURCINO
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OPPORTUNITY COST (TRADE-OFF) FOR DIFFERENT MAINTENANCE STRATEGIES AND RAILWAY TRACKS IN THE AMAZON
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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.
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LEDA DE AZEVEDO RACANELLI
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PRODUCTION OF GEOPOLYMER FROM TAILINGS FROM THE WASHING OF AMAZON BAUXITE
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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.
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HAMILTON PESSOA PICANCO
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OTIMIZAÇÃO GEOMÉTRICA DE PÁS DE TURBINAS HIDROCINÉTICAS CAVITANTES SOB EFEITO DIFUSOR
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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.
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GILTON CARLOS DE ANDRADE FURTADO
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ENERGY GENERATION FROM RENEWABLE HYBRID SOURCES WITH PUMPED STORAGE
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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.
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DAVI EDSON SALES E SOUZA
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ENERGY RECOVERY IN WATER DISTRIBUTION NETWORKS USING PUMPS AS TURBINE A VARIABLE SPEED
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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.
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LUCAS PINTO BERNAR
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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.
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Data: 17/08/2022
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Residual fat; Activated carbon pellets; Chemical activation; Thermal catalytic cracking; Catalyst bed reactor, Liquid hydrocarbons.
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MANOEL RAIMUNDO DOS SANTOS JUNIOR
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SIMULATION OF THE DEACIDIFICATION PROCESS OF HYDROCARBON MIXTURES, IN COUNTERCURRENT ABSORPTION COLUMNS, USING SUPERCRITICAL CO2 AS SOLVENT IN THE ASPEN HYSYS SIMULATOR
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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.
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MAURICIO MAIA RIBEIRO
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STUDY OF THE INCORPORATION OF INDUSTRIAL WASTE, RED MUD AND KAOLIN, IN THE PROPERTIES OF POLYESTER MATRIX COMPOSITES REINFORCED WITH JUTE AND MALLOW FIBERS
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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.
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JESSE LUIS PADILHA
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Feasibility of generating energy from urban solid waste in small municipalities in the state of Pará
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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%.
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SHEILA BARBOSA PARANHOS
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METHODS OF OBTAINING AND CHARACTERIZATION OF CHITOSAN AND COPAÍBA BIOMEMBRANE FOR POTENTIAL USE IN WOUNDS
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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.
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DEBORA DIAS COSTA MOREIRA
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STUDY INFLUENCE OF PARTICLE SIZE DISTRIBUTION OF THE IRON ORE FINES TO LIQUEFACTION FOR THE MARINE TRANSPORTATION
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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.
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LINO ALBERTO SOARES RODRIGUES
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ANALYSIS OF DISTORTIONS AND RESIDUAL STRESSES IN STIFFENED PANELS WELDED WITH FCAW-ROBOTIZED AND CW-FCAW
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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.
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EDUARDO GAMA ORTIZ MENEZES
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EXTRACTION OF OIL FROM TUCUMÃ-DO-PARÁ (Astrocaryum vulgare) USING SUPERCRITICAL CO2 AIMING FOR SCALE-UP
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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..
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ELISANGELA DA SILVA FERREIRA
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SYNTHESIS AND CHARACTERIZATION OF CHITOSAN MEMBRANE WITH GREEN BANANA EXTRACT AND ANDIROBA FOR HEALING OF EPITHELIAL INJURIES
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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.
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LIANNE MARIA MAGALHAES DIAS
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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.
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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.
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PATRICIA BITTENCOURT TAVARES DAS NEVES
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ARTIFICIAL INTELLIGENCE MODEL FOR ESTIMATING DEFORESTATION CONSIDERING THE ROAD TRANSPORT NETWORK IN THE STATE OF PARÁ
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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 .
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PAULO BISI DOS SANTOS JUNIOR
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Study of the depolimerization process of waste from polymethyl methacrylate resins (PMMA) through pyrolysis
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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).
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