Programa de Pós-Graduação em Engenharia de Recursos Naturais da Amazônia - PRODERNA/ITEC

URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/4044

O Programa de Pós-Graduação em Engenharia de Recursos Naturais da Amazônia (PRODERNA) do Instituto de Tecnologia da UFPA (ITEC) da Universidade Federal do Pará (UFPA), em nível de Doutorado, tem como objetivos principais: formar quadros profissionais qualificados na área de Engenharia de Recursos Naturais; incentivar a pesquisa e o aprofundamento dos estudos técnicos e científicos relacionados ao uso e a transformação de recursos naturais; e contribuir para o desenvolvimento científico e tecnológico da região Norte.

Navegar

Agora exibindo 1 - 20 de 132

Acesso aberto (Open Access)
Estudo e avaliação do uso de resíduos do processo Bayer como matéria-prima na produção de agregados sintéticos para a construção civil
(Universidade Federal do Pará, 2010-03) SOUZA, José Antônio da Silva; QUARESMA, João Nazareno Nonato; http://lattes.cnpq.br/7826389991864785
The large amount of solid waste coming from mines and metallurgical industries became a serious social-environmental problem. The physical and chemical features of this material can raise a great interest in other industries. The ceramic industry might be a great costumer for most of this material, since it can supply the current lack of raw material. The red mud, main industrial residue of the alumina manufacturing, has been a very interesting input for several kinds of aggregates manufacturing used for the concrete production in civil engineering. In this context, this paper deals with studies concerning the red mud recycling to be applied as raw material for the synthetic light aggregate production to be used as an alternative material in the civil construction industry. This is because of its physical-chemical features and the large amount annually produced (around 10 million tons within two factories in the North of Brazil). The studies completed in this work show the feasibility of aggregates manufacturing, with different properties and possibilities. These properties depend on the parameters control such as content of free silica and clay, and the sintering temperature. Such variables allow to perfectly controlling the glassy phase formation which is responsible for the aggregate properties such as: porosity, mechanical resistance and density. This material can be used for conventional or special concretes to supply the civil engineering needs.
Acesso aberto (Open Access)
Transporte pneumático fluidizado: estudos de casos aplicados à indústria do alumínio primário
(Universidade Federal do Pará, 2011-08) VASCONCELOS, Paulo Douglas Santos; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
This work is a contribution to science and applied technology developed to fluidized bed and fluidized motion conveying used in the powder handling of the industrial processes. In the case of fluidized bed it is proposed an empirical equation to predict the minimum fluidization velocity for the fluoride alumina, crust powder and others powders used in the industrial processes with good results compared with the experiments and the equations available in the literature. It was also studied the constitutive equations to predict the behavior of the angle of repose and interparticles friction as a function of the superficial velocity of fluidization. In a second step it is proposed an equation to predict the capacity of the Air Pneumatic Fluidized Conveyor with good results compared with the experiments for fluoride alumina. The Air Fluidized Conveyor is a contribution to applied technology reducing the consumption of energy, it operates even in upward direction, and so, decreasing the rate kWh/ton in the powder handling of the industrial processes.
Acesso aberto (Open Access)
Contribuição à análise do transporte pneumático em fase diluída
(Universidade Federal do Pará, 2011-10) GOMES, Luiz Moreira; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
This thesis is a contribution to the dilute-phase pneumatic conveying analysis. The survey of the key parameters of a pneumatic transport of bulk solids which are: the minimum conveying air velocity and pressure drop in horizontal and vertical pipelines. Therefore, an analysis of the main correlations available in the literature is made focused on the prediction of such critical velocities, and so proposes the use the most reliable correlations. In this way, an equation to predict the pickup velocity of the particles at the bottom of a horizontal pipeline was also developed. Then was analyzed the behavior of the pressure drop due to the solids and system properties using two computer programs, one of them does not consider the pressure drop in the acceleration zone in its formulation (algorithm). So, it is possible to understand what is the contribution of the acceleration zone in the total pressure drop of system and which is the range of application of each program. It is also done through mathematical modeling, the sensitivity analysis of the initial porosity of the bulk solids in the pressure drop along the pipeline as a function of parameters such as: solids mass flowrate, pipeline length, particles density and pipeline diameter.
Acesso aberto (Open Access)
Solução de equações de balanço populacional usando a técnica da transformada de Laplace e filtro de partículas
(Universidade Federal do Pará, 2011-12) BATISTA, Clauderino da Silva; MACÊDO, Emanuel Negrão; http://lattes.cnpq.br/8718370108324505; QUARESMA, João Nazareno Nonato; http://lattes.cnpq.br/7826389991864785
The evolution of particle size distribution in many fields of applied science, such as crystallization, aerosols, colloids, and polymer processing, can be obtained by solving population balance equation (PBE). The Laplace transform technique with numerical inversion was used to solve an integro-partial-differential equation related to the mathematical modeling of the physical problem to study convective processes with birth and death rates of particles or aerosols. Such model is governed by the population balance equation (PBE), in which is taken into account the nucleation, growth and coagulation processes. A Bayesian method was employed to solve the hyperbolic and non-linear inverse problem and estimate the size distribution density function, thus predicting the dynamic behavior of the physical system. Specifically the particle filter with sampling Importance Resampling (SIR) has been applied as a method of solving the problem. From these solutions, numerical results were obtained and compared with those in the literature for particulate systems permitting a critical evaluation of the present solution methodology.
Acesso aberto (Open Access)
Desenvolvimento de um modelo via MEF para análise da dispersão de poluentes em rios, lagos e estuários
(Universidade Federal do Pará, 2012-03) LIMA, Rômulo Correa; BLANCO, Claudio José Cavalcante; http://lattes.cnpq.br/8319326553139808; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
Freshwater of good quality is a pre-requisite for social and economic development of a given region. Paradoxically, this same development is normally responsible for the pollution of their water sources, through domestic or industrial waste dumping without treatment, or through agricultural activities. In this way, the monitoring and the management of that sources are extremely important for the wellbeing of the people living in that region. Among the possible tools to auxiliary this management is the computational simulation of pollutant transport in the hydro medium. In this context, this work presents a computational procedure for the solution of the 2D advectiondiffusion- reaction equation, which is the basis for all the mass transport models. This process consists in the union of the finite elements and finite difference methods in the discretization of the spatial and temporal components, respectively. This methodology was evaluated with the help of tests with synthetic and real data. First one considered the case of mass transport by pure advection to ensure its stability in cases where the classical formulations fail. Second test simulated the transport of a hypothetical pollutant in a piece of a river and showed the correct effect of the drag due to advection and spreading due to diffusion. The last test evaluated the transport of total phosphorus in Agua Preta Lake from the pumped water of the Guama river and point sources located at the margins of the reservoir. The result of the simulation showed the potential of the algorithm to deal with cases closer to the reality.
Acesso aberto (Open Access)
Adsorção e dessorção supercrítica de carotenos e antioxidantes do óleo de buriti (Mauritia flexuosa, Mart) em leito de γ- Alumina
(Universidade Federal do Pará, 2012-03) CUNHA, Marcos Augusto Eger da; FRANÇA, Luiz Ferreira de; http://lattes.cnpq.br/6545345391702172; MACHADO, Nélio Teixeira; http://lattes.cnpq.br/5698208558551065
In this work we investigated the enrichment of antioxidants buriti oil (Mauritiaflexuosa Mart) adsorption process by supercritical. The adsorption was carried out experimentally by the method of frontal analysis in columns packed with y-alumina and 15, 20 e 25 MPa, 333 K, and flow of solvent QCO2 = 10,6 L/min, using an assembly of double columns of 81 cm3, tested and approved for use as a cell adsorption. The oil was buriti physic-chemically characterized according to the AOCS official methods and found to comply with the data reported in the literature. The composition of methyl esters was determined by gas chromatography (CG) and antioxidant activity by the method of capture of free radicals (DPPH). The adsorbent was characterized by fluorescence and x-ray diffraction, determining the particle size distribution, porosity and surface area by BET in each experiment, a material balance was performed in the adsorption column to calculate the mass of the adsorbed species in y-alumina in the process of supercritical adsorption. The influence of pressure on supercritical adsorption was investigated by examining the behavior of the isotherms. The Langmuir isotherm was used to model the experimental data of adsorption. The experimental results show an increased capacity adsorbent with higher pressures, showing a maximum of 90,9 ± 8,6 mg oil/g y-alumina, at 25 MPa. The adsorption supercritical buriti oil on γ-alumina using carbon dioxide as solvent appears to be an alternative method for extracting antioxidants from the includ carotenes.
Acesso aberto (Open Access)
Análise experimental e numérica da fluidização para aplicações industriais
(Universidade Federal do Pará, 2012-03) LOURENÇO, Reimar de Oliveira; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662; MACÊDO, Emanuel Negrão; http://lattes.cnpq.br/8718370108324505
The gas-particle fluidized beds have great importance in the processing industry, due to have a good effect of mixing between the phases, and high rates of heat and mass transfer, requiring it to lower power consumption. Some typical examples of industrial applications of this equipment can be found in processes involving catalytic reactions, catalyst regeneration, or the combustion and coal of gasification. The understanding of the fluid dynamic behavior of this equipment is of fundamental importance for the fluidized bed can be adapted to new conditions. The literature reports several studies of fluidized bed, reporting varied contributions already incorporated the knowledge of the operation. The CFD (Computational Fluid Dynamics) tool has proved a good alternative for understanding the operation of this equipment. The use of multiphase granular Eulerian model together with the conservation equations of mass, energy and momentum for each of the phases present, has shown success when applied to fluidized beds. Overall, this work is to study the behavior of the fluid dynamic flow of glass beads and alumina in conventional fluidized bed type gas-solid, varying models Gidaspow, Syamlal-O’Brien and Wen-Yu, as well as Turbulence Models K-ε and RSM. More specifically, the work seeks to study the behavior of the fluid-dynamic equipment, by monitoring the most important fluid-dynamic parameters, among which we highlight the minimum fluidization velocity of the same, the pressure drop at minimum fluidization equipment, its porosity and expansion of the bed particles, also at minimum fluidization. Experimental tests were compared with numerical simulations using CFD (Computational Fluid Dynamics) tool, in which good agreement of the simulated results compared to experimental results.
Acesso aberto (Open Access)
Estudo da extração de compostos de ferro da lama vermelha visando a extração e/ou recuperação de compostos de titânio
(Universidade Federal do Pará, 2012-04) MAGALHÃES, Edilson Marques; MACÊDO, Emanuel Negrão; SOUZA, José Antônio da Silva; http://lattes.cnpq.br/8718370108324505; http://lattes.cnpq.br/6157348947425968
The main concerns about waste generation are focused on the effects that these materials can have on human health and the environment, since the hazardous waste generated by industries need particular attention and care, because when improperly managed, become a serious threat to the environment. In this context, this work shows the studies for recycling of red mud as raw material to obtain titaniumcompounds. The study covers three hydrometallurgical routes: red mud calcined at 900°C (LV900), red mud without thermal treatment (LV-STT) and red mud sintered in a reducing atmosphere (LV1300). The leaching experiments were performed with temperature values of 60, 80 e 90°C and sulfuric acid concentration of 20 and 30%. Together with the analysis mathematical modeling was carried out leaching process. Such analysis shown that the red mud can be applied as a source of alternative raw material for the concentration and subsequent recovery of titanium compounds. The kinetic modeling of the curves of data extraction as a function of time and the mathematical model developed in this work, shown that, the chemical reaction step describes the leaching tests. The developed model also allowed obtaining kinetic parameters such as activation energy and velocity of chemical reactions of the leaching process.
Acesso aberto (Open Access)
Metodologia para avaliação do grau de sustentabilidade utilizando a lógica fuzzy: aplicação na indústria madeireira
(Universidade Federal do Pará, 2012-05) LEAL, Maria de Fatima Mendes; MONTENEGRO, André Augusto Azevedo; http://lattes.cnpq.br/1135221873341973; MANESCHY, Carlos Edilson de Almeida; http://lattes.cnpq.br/3638082762153871
The economic needs of industries as well as the necessity of preservation of the environment require a development of its activities in a way that is environmentally responsible and, consequently, with the proper use of natural resources. The economy of the state of Pará is based on agriculture, livestock and vegetable and mineral extraction being the last one represented, mainly by wood. Certainly, it will contribute to the sustainable use of forest resources, an assessment that quantifies the subsystems environmental, economic and social, that are the basis of sustainability. Studying the segment of improvement and exportation of wood it was used fuzzy logic in a proposed methodology for determining the degree of sustainability that, in this study, may vary on a scale from 0 to 10, quantifying not only the condition of sustainability itself, but also indicating which subsystems or components need to be improved. The determination of public policy for the forestry sector can be performed using the same methodology, since that the necessary legal adjustments are made.
Acesso aberto (Open Access)
Desenvolvimento de sistema computacional para avaliação de lodo de esgoto sanitário como biomassa na geração de energia
(Universidade Federal do Pará, 2012-06) SANTOS, Yvelyne Bianca Iunes; PEREIRA, José Almir Rodrigues; http://lattes.cnpq.br/9918600634569244
Development of a computational system to assess sewage sludge sanitary as biomass to generate energy in combustion processes, taking into account Brazilian technical and environmental norms. Classes were created and implemented in the system to assess sewage sludge as energy potential and considered limits established in the norms NBR 10004/04, NBR 10004/87 and CONAMA Resolution nº 316/2002 for adverse environmental impacts, damages or risks to public health , identifying the feasibility of use of this residual as biomass to generate energy in combustion processes. The system was developed using a Model-View-Controller (MVC) software considered an architectural pattern, with method represented by logical rules, whose input data were the results from laboratory determination of sewage sludge samples, test processing and logical sequence of rules, and reports to enable the user to make a decision. To validate the system it was used results from technical work on the use of sewage sludge as biomass to generate energy in experimental scale, observing that the limits adopted in the system were appropriate as parameters to evaluate the energy potential of the sampled sludge, its toxicity and air pollution; that the explanatory and alert messages have been clearly sent; that the logical sequence of rules had been progressively implemented; and that the values obtained in the system had been compatible with the validation works. Finally, it was concluded that the system developed may be used to expedite decision-making, mainly, in waste treatment plant with large quantities of sludge.
Acesso aberto (Open Access)
Análise dos impactos da dinâmica de sólidos e de nutrientes na qualidade da água de ambiente lêntico utilizado no abastecimento de comunidades amazônicas
(Universidade Federal do Pará, 2012-08) SARAIVA, André Luis de Lima; PEREIRA, José Almir Rodrigues; http://lattes.cnpq.br/9918600634569244
The springs of Utinga, formed by the Bolonha and Água Preta lakes, are contained in an Área de Proteção Ambiental - APA and are used by the Companhia de Saneamento do Pará - COSANPA, to supply the population of the Região Metropolitana de Belém - RMB. These springs are formed by Guamá River, where water is captured and sent to the Água Preta lake by pumping, which in an artificial channel with gravity flow, feeds the Bolonha lake, and since it is pumped to the Estação de Tratamento de Água - ETA. The main problems of pollution / contamination of water sources appeared to advancing urban disordered, giving rise to the improper release of sewage and solid waste from neighborhoods, slums and housing estates close to the main springs. The objective of this study was to use tools to support monitoring and knowledge of water quality in the Água Preta lake, to prevent and / or correct degradation processes. These tools are multivariate analysis of abiotic parameters and chlorophyll a, nutrient balance and hydrodynamic modeling aiming to observe the dispersion of sediment transport. Samples were collected in surface water at three points strategically chosen to assess the anthropogenic influence in the Água Preta lake and sediments that are suspended matter carried into the lake. The sampling points were georeferenced using GPS (GARMIN Model) and the sampling of surface water were performed with the Van Dorn bottle 2.5 L and transported to the Laboratório de Química Ambiental (LQA), located at the Universidade Federal Rural da Amazônia, for further analysis. Samples were collected during the months of March, May, June, August, September and October in 2010, coinciding with periods of higher and lower rainfall. The data of abiotic parameters and chlorophyll a were analyzed by methods of descriptive statistics and principal component analysis. Analyses were also carried out analysis of the mass balance of water and nutrients and adopted the use of hydrodynamic model of the modeling program SisBAHIA (Sistema Base de Hidrodinâmica Ambiental), aimed to mimic the hydrodynamic conditions of the Água Preta lake during a year. Through these simulations were generated maps of surface currents to observe the different patterns of movement, since the use of models have played an important role in planning and development of alternative scenarios that include the proper diagnosis of the water systems in its structure, process and dynamics. The parameters studied showed variations during periods of lower and higher rainfall, higher contribution being found in point 2 in respect of turbidity, color, DO, nitrate, NT, chlorophyll a and suspended solids were found larger contribution in points 2. The other parameters (N -ammonia, BOD and PT) had contribution in points 1 and 3, indicating a source of organic pollution, due to domestic sewage, since there are nearby dumping of sewage. In the mass balance was found that both the PT and NID were influenced by the load of water river Guamá during the lower rainfall. While with high rainfall total phosphorus load was higher due to higher contribution from dewatering of sewage released into the reservoir. The retention time for the PT was 180 days and 536 days was NID. Through this balance could quantify the entry, retention and export of nutrients as well as to evaluate the potential for eutrophication of reservoirs. In the hydrodynamic model showed that the distribution of the module speed was identical for each month of the year, regardless of wind direction, with the riparian vegetation around that water environment this important role in reducing the speed modular surface of the water. However near the output channel of pond water was observed a change of speed 0.32 m /s in the rainy season and 0.28 m / s during the dry period that can be related to the precipitation. Furthermore, the input of water in the tank forms a vortex tending to sedimentation process, a fact observed in the bathymetry. The sedimentation at this point be given especially in periods with lower precipitation, because COSANPA increases the flow of water intake to maintain the level of the reservoir to supply the Região Metropolitana de Belém, providing the greatest contribution of suspended sediment, a fact observed with the parameters of turbidity, color and suspended solids, which have higher concentrations at this point and a decrease as they move away to step 3 (water outlet channel for the connection). These tools are of great importance for maintenance of the spring, since they will allow diagnosing the lake capacity tends of retain and remove nutrients as well as the process of the hydrodynamic circulation allowing check sites that can have a major and minor deposition of materials suspended in water column. Through this study will provide data that subsidizes the competent authorities the future and help in the conservation of other sources used to supply water to cities.
Acesso aberto (Open Access)
A técnica da transformada integral na modelagem e simulação de processos de separação de metais por membranas difusivas poliméricas
(Universidade Federal do Pará, 2012-11) CARDOSO, Simone de Aviz; QUARESMA, João Nazareno Nonato; http://lattes.cnpq.br/7826389991864785
The Generalized Integral Transform Technique (GITT) was used in the analysis of the metal extraction process with flat and tubular membranes. For the study of flat membrane, we analyzed the extraction of metals cadmium, Cd (II), gold, Au (III) and palladium, Pd (II) in polymeric diffusive membrane with Aliquat 336/PVC and the equations of chemical species were solved by the GITT methodology. In a second study, the Coupled Integral Equations Approach (CIEA) was used to analyze the same problem. In the study of hollow-fiber tubular membrane, the GITT methodology was also utilized for analyzing the influence of transport conditions for the solute of interest at the interface fluid and membrane phases of a mass separation process in tubular membranes as a function of the governing parameters of the problem. In this type of extraction, liquid extractants are used in the pores of the fiber membrane to facilitate the separation of the mass. In both studies, comparisons were made with those results from the literature demonstrating the potential of this technique in dealing with problems of such natures.
Acesso aberto (Open Access)
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
(Universidade Federal do Pará, 2013-02) VENANCIO, Luis Carlos Alves; SOUZA, José Antônio da Silva; http://lattes.cnpq.br/6157348947425968; MACÊDO, Emanuel Negrão; http://lattes.cnpq.br/8718370108324505
The bauxite refining using the Bayer process produces 0.7 to 2.0 tons of the residue known as red mud and about 1.0 ton of CO2 for each ton of alumina produced. The bauxite residue, although not particularly toxic, poses risks to the environment due to its large volume and reactivity. According to the latest technology, part of the moisture is removed and it is stacked on sealed areas specially constructed. More than 95% of the bauxite residue that has been produced (2.6 Bt until 2007) was discarded, especially in ponds on land. This thesis shows the design, construction and operation of a pilot scale gas liquid mass transfer unity with the objective of testing the reduction of the reactivity of the bauxite residue through a reaction with flue gas. As an additional gain, there is a reduction of carbon dioxide and sulfur dioxide emissions. This unity, with three reactors, was designed in order to consume minimal power, process the effluent as efficiently as possible and minimize the investment cost. Twenty-five experiments were realized with duration from 80 to 520 minutes each. The gases were analyzed at the entry and exit with electrochemical cells and non-dispersive infrared sensors. The pH was monitored during and after the reaction in order to evaluate the short and long-term results as well as the stability of the reactions. It was demonstrated the viability of reacting the bauxite residue with the flue gas from the refinery without previous processing with the stabilization pH reaching 10.5.
Acesso aberto (Open Access)
Estudo da extração de cobre utilizando contactores com membranas como alternativa ao processo convencional de extração por solvente
(Universidade Federal do Pará, 2013-12-27) OLIVEIRA, Kleber Bittencourt; FERRAZ, Helen Conceição; http://lattes.cnpq.br/1820877582714129; MACÊDO, Emanuel Negrão; http://lattes.cnpq.br/8718370108324505
This paper studied the extraction of copper using membrane contactors as an alternative to conventional SX process. The relevant process parameters as type and concentration of extractant solvent, the strip solution, operating time and pH were investigated. Furthermore, a mathematical model was developed from a system of partial differential equations resulting from the mass balance in the membrane contactor system, using as the solution methodology of Integral Technique Coupled (CIEA). The experimental studies conducted in this study showed that use of membrane contactors in liquid-liquid extraction of copper is a promising and viable technology, with the potential to replace the method of solvent extraction by direct contact adopted currently yielding 100% extraction LIX 84I copper using 20% (v/v) as extractant, kerosene as solvent and H2SO4 strip solution in an operation time of 80 minutes. The results obtained by mathematical modeling and simulation of the physical problem analyzed in this study were compared with experimental results and shown to be satisfactory, demonstrating the ability of CIEA in treating problems of mass transfer in membrane systems with contactor.
Acesso aberto (Open Access)
Uma nova proposta de avaliação de fogões à biomassa
(Universidade Federal do Pará, 2014-03-14) CANTO, Sérgio Aruana Elarrat; MANESCHY, Carlos Edilson de Almeida; http://lattes.cnpq.br/3638082762153871
This research presents the method of Global Assessment of Biomass Stoves - (MAGOF) which innovates by considering a wood stove as a household equipment, thus a product, unlike the known evaluation protocols that prioritize energy aspects. The MAGOF determines the Global Performance index by employing 72 Quality Requirements regarding the product’s life cycle, distributed by affinity amongst 5 Attributes that indicate Performances Of Specific Design, Environmental, Featured, Energy, where it is inserted the Water Boiling Test (WBT), and Economic Specific Performance. These innovative particularities offer relevant information for designers, researchers, manufacturers, users, consumers, investors, regulator or supervisory governmental institutions and other actors. This information favors the decision - making process, technological innovation, improved stoves, health and safety of users, environmental preservation and reflects on the economy. The MAGOF is of global relevance since it is aligned with global efforts in seeking comprehensive solutions to the problems arising from the inadequacy of biomass stoves traditionally available, since about 2.5 billion people use wood or charcoal to cook on all continents, and the World Health Organization (WHO) found out that about 1.5 million people die annually from respiratory diseases caused mainly by smoke emitted by biomass stoves. The survey also brings an application of a MAGOF on a stove produced by the Ecofogão company, and an Amazonian handmade stove. A performance comparison is presented, resulting in consistent values regarding other stoves of the same category.
Acesso aberto (Open Access)
Estudo da técnica de infusão de resina aplicada à fabricação de compósitos de matriz poliéster reforçados por fibras naturais da Amazônia
(Universidade Federal do Pará, 2014-03-26) RODRIGUES, Jean da Silva; FUJIYAMA, Roberto Tetsuo; http://lattes.cnpq.br/3165747089941318; SOUZA, José Antônio da Silva; http://lattes.cnpq.br/6157348947425968
In this work were produced unsaturated polyester composites reinforced by fibers of curaua, jute and raffia, arranged in the form of fabric in plan style and aligned fibers. The composites were manufactured by resin infusion process, studying the main parameters that govern the manufacturing method, such as permeability and porosity of the reinforcement and architecture of infusion. Natural fibers were characterized according to their physical, morphological and mechanical properties. The curaua fiber reinforced composites were made using fibers in nature and treated by an alkaline NaOH solution at different concentrations. The composites were characterized in tests of tensile and impact strength, beyond of the determination of their physical properties such as density, porosity and volume fractions of the constituents. The results showed that the composites obtained better performance in tensile and impact were those reinforced with aligned curaua fibers manufactured under vacuum of 101.3 kPa. The evaluation of the cross section of the specimens showed that composites can provide partial saturation of wires or fiber reinforcement due to the vacuum level used mainly in reinforcements in the form of fabric with relatively larger diameter wires. The infusion process proved to be a good method of making composites reinforced with natural fibers, because in addition to being more environmentally friendly because it is a closed mold process, enabled the manufacture of products with high fiber content and good mechanical properties.
Acesso aberto (Open Access)
Regionalização e estimativa de chuvas do estado do Pará
(Universidade Federal do Pará, 2014-04-25) GONÇALVES, Mariane Furtado; BLANCO, Claudio José Cavalcante; http://lattes.cnpq.br/8319326553139808
In Amazon region, a factor which prevents the most comprehensive knowledge of water resources is the lack of hydrological data (flow and precipitation) of small and medium-sized watersheds. This is mainly due to size of the region, which increases the costs of implementation and operation of the network. In this context, this work aims to develop a model of regionalization and estimated rainfall for the state Pará For this, we applied a methodology for delineation of homogeneous regions of precipitation through the cluster analysis was then determined probability of rain for some point rainfall homogeneous region obtained with the cluster analysis by applying probability functions, and finally was given estimates of rainfall heights, using multiple. For every step we used annual and monthly averages precipitation of a time series of 31 years (period 1960-1990), obtained at the Center for Climatic Research, Department of Geography, University of Delaware, Newark site, DE, USA. Among the analyzed years, years were selected with the occurrence of El Niño and La Niña. Using the agglomerative hierarchical Ward method, having as similarity measure the Euclidean distance for annual and monthly rainfall averages six homogeneous regions of precipitation were found, except for monthly averages for rainfall series with the occurrence of El Niño and La Niña, who has four and five homogeneous regions, respectively. After the definition of homogeneous regions, probability models (Normal, Gumbel and Exponential) were fitted to determine the heights of the three sequences of rainfall time series, applied the chi-square test for this check. After the calibration step to annual rainfall, it was found that the model is best fit normal distribution the probability of exceedance observed, since average monthly precipitation for the Gumbel distribution model got better grip frequencies of exceedance. The above models were validated using the rainfall series of 12 stations of the Agência Nacional de Água (ANA), considered as target stations. At this stage, it was observed that to mean annual rainfall occurred adherence of the data to all the rainfall stations targeted because they presented the results of applying the chi-square test less than 3.84 (for normal distribution functions). And it was also found that for average monthly rainfall, there was adherence of the data to all the rainfall stations target. To simulate rainfall heights were tested for calibration models of power, according to Power and Linear model by means of multiple regression. As a criterion of performance models, the percentage relative error was used. For time series containing series every year and with the occurrence of La Niña, the model showed a lower relative. As for series with the occurrence of El Niño, the model of power had minor errors. As for the probabilistic models, the calibration results of the multiple regression models were validated with the use of rainfall stations of the ANA. In the validation step for series containing every year the percentage errors ranging from 0.2 to 39.2%, as when used in El Niño years there has been an increase in error ranging from 1.9 to 54.8%, and La Niña years from 8.5 to 55.9%. Although some estimates have had considerable errors, above 50%. The results of applying this methodology are important for a better understanding of rainfall in the state of Pará and the Amazon, and can serve as a tool for better planning and management of water resources in the region.
Acesso aberto (Open Access)
Análise experimental do processo de extração do óleo essencial de Puxuri [Licaria puchury-major (Mart.), Kosterm., Lauraceae] por arraste com vapor
(Universidade Federal do Pará, 2014-04-30) MAFRA, Eduardo de Souza; FARIA, Lênio José Guerreiro de; http://lattes.cnpq.br/7428609361678173
Analyse experimentally the extraction process of the essential oil of seeds and aerial parts of puxuri for drag with steam. The puxuri, [Licaria puchury-major (Mart.)] Kosterm., Lauraceae], is a species of the Amazon forest with great potential for the Bioproducts Industry (pharmaceu-ticals, cosmetics, food and natural pesticide) due to the presence of safrole in its essential oil. This work is an anatomical study and physical and chemical characterization of plant parts used for oil extraction. Studying the kinetics of drying of seeds, thin branches and leaves of puxuri and quantifies the influence of convective drying in fixed bed in safrole content and moisture content. Through statistically designed experiments, identify levels of process variables: mois-ture content, particle size and extraction time of samples of seed of puxuri, that optimize both answers the responses: in essential oil yield and content of safrole, its major component, within the experimental domain adopted and 90% confidence (α = 0.10) in the extraction process of the essential oil by steam drag. Chemically analyzed the essential oil of puxuri by GC-MS and iden-tifies the chemical composition in terms of their senior constituents. Using the gravimetric ap-proximation method static with concentrated solutions, desorption isotherms are obtained for puxuri seeds powder, in temperatures 15, 25 and 35ºC. The experimental data hygroscopic equi-librium, fits very well the GAB model, being estimated the heats of sorption liquid and inte-grals, in addition to the equilibrium moisture content in monolayer and other constants in the equation. Noted low toxicity of essential oil of puxuri and the solid residue of extraction can be used as material for the production of saponifiable transparent soaps to cold.
Acesso aberto (Open Access)
Reciclagem de resíduos industriais na fabricação de argamassas e placas cerâmicas premoldadas fabricadas a partir de matriz sílico-aluminosa destinadas a construção civil
(Universidade Federal do Pará, 2014-05) CARVALHO, Ronaldo Nonato Ferreira Marques de; MACÊDO, Alcebíades Negrão; http://lattes.cnpq.br/8313864897400179; SOUZA, José Antônio da Silva; http://lattes.cnpq.br/6157348947425968
It is proposed to manufacture plates in structured network of PVC pipes, filled with mortar composed of rejected materials of civil construction, and coal fly ash, hydrated lime and Portland cement, inspired by the traditional technique of earth construction called “taipa de mão”, employed in the State of Pará, Brazil. The final product is a contemporary and ecological construction system for the execution of partition panels, aiming the decrease and the reuse of waste construction’ materials, whose disposal causes environmental damage. The rejected materials have physical-chemical characteristics which allow its recycling, increasing the duration of their Life Cycle. Aiming to develop mortar’s material having characteristics as plasticity, elasticity and mechanical strength were made experiments with traces consisting of construction waste and Portland cement, duly processed and dosed for the confection of test bodies. These were submitted to the tests absorption of water, porosity, density, compressive strength and toughness, resulting in the selection of the most appropriate compound, in respect to use in manufacturing mountable ceramic plates for use in partition panels. The plates were submitted to the tests of compression and tension.
Acesso aberto (Open Access)
Produção de biodiesel a partir do processamento das oleaginosas amazônicas compadre-do-azeite (Plukenethia polyadenia) e comadre-do-azeite (Onphalea diandra)
(Universidade Federal do Pará, 2014-06) FURTADO, Matheus Braga; MACÊDO, Emanuel Negrão; http://lattes.cnpq.br/8718370108324505; FARIA, Lênio José Guerreiro de; http://lattes.cnpq.br/7428609361678173
Analyse experimentally the production of biodiesel from oilseeds processing compadre of Amazonian oil (plukenethia polyadenia) and Ruth-of-oil (Aubrey onphalea), as a potentially viable alternative to compose the energy matrix. Since the Industrial Revolution in the 19th century, the world energy matrix has always been based on fossil fuels. With the scarcity of such fuels, the rise of prices caused with the constant conflicts in major producing regions, has become the research into renewable sources increasingly attractive. The study of new sources of vegetable oils as alternative energy is important for the Country, particularly for the Amazon; enabling structure of oilseeds production chains in the region, generating employment in the field, distributional effects on regional economy and a vector of sustainable development in the Amazon, no aggression to the environment. The purpose of this work is to study two species of the family euphorbiaceae, lianas and polyadenia Onphalea Plukenethia diandra, better known as compadre of the olive oil and the olive oil Cummer respectively, oil-producing; extract and characterize them, suggesting possible applications and using them for the production of biodiesel through Transesterification using methyl potassium hydroxide as a catalyst, in the case the process based on statistical tests planned. The influence of input variables: oil/alcohol concentration, temperature and concentration of catalyst on biodiesel yield response by response surface methodology (RSM) employing the Box-Behenken planning. The aim is thus to add value to a tailing kaolin processing industry, using zeolites produced this material as a catalyst to KOH, comparing the efficiencies of the two treatments. The Box-planning Benhken proved efficient to optimize the homogeneous catalysis of the biodieseis, concluding that the concentration of the catalyst was the variable controlling the production process of biodieseis, and the increase of its concentration cause negative and undesirable influence the yield of the product.