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Navegando por Assunto "Biomass"

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    Alternativas para o abastecimento energético dos fornos de indústrias cerâmicas localizadas no município de São Miguel do Guamá-PA
    (Universidade Federal do Pará, 2013-08-14) ROCHA, Alexander Lobo; NEVES, Renato Martins das; http://lattes.cnpq.br/6538317425557058
    Economic and environmental differentials incorporated biomass energy has driven the spread of supply and use of biofuels in developed and developing countries. In the state of Pará (Brazil), the growing demand for biomass like acai lump and legalized firewood, specially related to the performance of the ceramic industry in the São Miguel do Guamá county and other industrial segments, pints to a possible shortage of these energy resources. Thus, initiative is needed to search for alternative fuels that are capable of not only ensuring the energy supply necessary for the current and future ceramic production of these industries, but also to ensure the continuation and conservation of renewable natural resources in the region. This work consolidates research among member companies of the Association of Ceramics Industries of São Miguel do Guamá, which are located in this municipality, using as a sample the ceramic companies seeking alternative bioenergy, along with the research among the agro-industries and farmers present in other municipalities of the state of Pará. The objective is to identify alternatives for energy supply in ceramic kilns, considering the use of renewable energy sources and opportunities for reducing the cost of its acquisition through the practice of return shipping. It was used as a research strategy case study in five moments of semi-structured interviews guided by questionnaires. The results obtained indicate that there is opportunity to supply biomass matched with the needs of the surveyed ceramic companies, with the potential to meet repressed energy demands and allowing the continuation of strategic business in Pará, as at this time, the growing civil construction industry.
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    Aproveitamento da biomassa flutuante do Rio Madeira para geração de energia elétrica
    (Universidade Federal do Pará, 2010-05-24) BACELLAR, Atlas Augusto; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
    The universal provision of electricity remains far from achieved in the Brazilian Amazon, given the geographical obstacles, the dispersion of its inhabitants, the indistinctness of appropriate technologies, and the economic obstacles. Governmental action was taken in 2003 with the creation of the Light for All Program (PLpT), with the goal of bringing electricity to all rural consumers by 2010. In addition, the National Electric Power Agency, ANEEL (Agência Nacional de Energia Elétrica), which is responsible in Brazil for the electrical sector regulation, has issued a determination of compulsory access to electricity by 2015. This study describes research conducted on the Madeira River, in the Brazilian Amazon, where the electric needs of the communities and small towns along the river can be satisfied through the gasification system, using as a renewable feedstock the wood-fuel biomass deposited on the riverbed, derived from natural processes, which the Ministry of Transport is already legally obligated to remove in order to provide safe navigation along the river. The first part of the study was dedicated to review Brazilian power system, Universal access to electricity in Brazil, renewable sources of energy in the Amazon region, technologies to produce electricity using biomass as source, Brazilian power sector subsidies, the Madeira River, its characteristics and economic importance and investment analysis tools. Next, quality and quantity information of the biomass collected from the river along the years was taken from AHIMOC, the Federal Organization responsible for the Madeira River navigability. Then a physical-chemical analysis was made at the UFAM’s laboratories, using biomass collected in a field trip. The biomass power potential and the technological power production routes using biomass were evaluated with these data after comparing the results with available literature. Subsequently information about householders and communities located at the Madeira River was obtained with the State Utility. Once the available biomass, the technology routes and the possible consumers were characterized, the study evaluated technology, economy, environment, social and legal aspects. The study results show the competitiveness of gasification comparing to diesel thermoelectric plants, along with its advantages in helping Brazilian universal electrification program, which implementation depends on public policies with the obligatory participation of the Ministry of Mines and Energy, Ministry of Transports and The Ministry of Environment, and also the attractiveness potential private capital participation which could contribute to reduce public investment. The results should help future studies in others areas with similar phenomena and the opportunity to use another types of local biomass in Gasifier systems.
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    Atendimento de energia elétrica domiciliar para comunidades isoladas de baixa potência do interior do estado do Pará através de um gaseificador de 1kw
    (Universidade Federal do Pará, 2006-12-11) BRITO NETO, Osmundo Batista de; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
    In Pará State, almost 21% of its population has no access to use of electric energy in their residence. To this universe belongs the target audience from this report, that are the isolated communities. Due the large territorial extension and hydrographic basin in Pará State, this communities will have many difficulties to be served by the extension of distribution network. The proposal of this report consists in the use of the Açaí seed as biomass to an Indian co-current and open top gasifier of 1 Kg/hour, adapted and adjusted to the specifications of this region; the gasification system is connected to a generator of 2 KVA (Diesel or Gas), to supply with electric energy for the isolated communities where already exists the biomass as a result of the Açaí seed processing that is been considered as garbage. In this context, the governmental programs were examined in order to support this proposal, using the proposed system as one of many options to serve with electric energy by alternative source.
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    Desafios e oportunidades para o acesso universal à energia elétrica na Amazônia
    (Universidade Federal do Pará, 2015-02-20) MUNIZ, Rafael Ninno; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
    The Brazilian energy planning has been progressively emphasizing the use of renewable energy sources, however for some initiatives such as the Light for All Program, these energy alternatives are being treated as a secondary activity and difficult to implement. This work aims to analyze how the Brazilian government has been adapting its institutional structure, technology and funding to provide universal access to electricity in remote areas. According to official information, this initiative has proven effective in its first phase, which was developed by the extension of conventional network. However, the study concludes that the program is currently not converges to full compliance with the access to electricity in remote areas in the Amazon and three main challenges were identified. There is a need for adjustment of current institutional structures, harmonize technologies to the regional context and use government funds more effectively. The research points out ways and alternatives to what is being done in isolated systems, and presents two case studies which have been applied to decentralized power generation with renewable sources of biomass in isolated community, and the energy utilization of municipal solid waste in the municipality belonging to the isolated system. These practical examples are proposed to contribute to the results of the study for the development of public policies, research projects, meet technology providers and promote energy and residuary solutions for municipalities and communities belonging to national isolated system, aiming to achieve universal access to energy electricity in remote areas in the Amazon.
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    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.
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    Estudo da sinterização em reator vertical de leito fixo: desenvolvimento de processo para produção de agregado sintético a partir de cinza volante e biomassa
    (Universidade Federal do Pará, 2016-05-19) QUARESMA, Danielly da Silva; SOUZA, José Antônio da Silva; http://lattes.cnpq.br/6157348947425968; MACÊDO, Emanuel Negrão; http://lattes.cnpq.br/8718370108324505
    The synthetic aggregates have been employed in civil construction as a measure for the reduction of mineral extraction. Within this context, the recycling of industrial waste configured today as the basis of the majority of processes to reduce the exploitation of mineral resources. This paper presents the formulation of a process of environmental character and self-sustaining from an energy point of view parameters to develop a process for the production of synthetic aggregate from fly ash and biomass fixed bed reactor. Thus, for the production of aggregate pellets were made from a mixture of clay, fly ash and charcoal in fixed proportions. The reactor is filled with 20% pellets (6.35 mm > pellet ≥ 4 mm) and 80% charcoal (3.36 mm > carbon ≥ 1.70 mm) rated for promoting the efficiency of combustion reactions and subsequent sintering process at different air velocities (Darcy at 20 °C) of 0.0059 m.s-1 (1º Experiment), 0.0098 m.s-1 (2º Experiment) and 0.017 m.s-1 (3º Experiment). By means of X-ray diffraction and scanning electron microscopy was identified the presence of mullite in synthetic aggregate. This material is characterized as lightweight aggregate, in accordance with current standards. With synthetic aggregates manufactured to lightweight concrete, according to the established standard, without structural function in civil construction, but with applications of moderate resistance and may be used in the counterfloor. The process if showed interesting for the sintering of aggregates with good adhesion to the matrix of cement, and can easily be controlled by composition, granulometry, temperature gradient and gaseous flow, reducing environmental impacts, to the extent that the material produced implies in not extraction of natural aggregates.
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    Estudo da viabilidade econômica para a utilização da semente da euterpe oleracea mart. (açaí) como recurso energético
    (Universidade Federal do Pará, 2008-07-09) LUCZYNSKI, Miroslawa; MACHADO, Luiza Carla Girard Teixeira; http://lattes.cnpq.br/9773700229115395
    This work had as objective the study of the economic viability for the Euterpe oleraceas Mart. (açaí) seed use as energy resource in the city of Belém-PA. Initially, it was realized a field survey of the sail points and quarters of biggest production of açaí, carrying through after that the assays of the termogravimetric properties of the seeds that are: Humidity text, volatile text, cinzas text, fixed carbon text and superior calorific power. The survey points made possible the creation of a data base, using the Microsoft Software Access, which supplies reports with the identification of the proprietors name, as well as the number of bags that is it processes per day, weight of bag and its energy potential. It was used still the Microsoft ARC VIEW, of easy interaction with Access that made possible the creation of an up to date map of the points for the city of Belém-PA. With those data a study of the transport routes was made in the Geographic Information System (GIS) GOOGLE EARTH. There were determined routes, through the Centroid method, which is the point of highest concentration of the variable of study, in this case, the açaís seed, for the transport of biomass to its final destination that is the UFPA, where if it finds the plant that uses the biomass as combustible to generate energy. When calculating the economic viability there were used the plant of Energy and Biomass of the Group of Energy, Biomass and Environment (EBMAs) together with the data of the consumption of electric energy of the UFPA in the period from 06/2006 to 06/2007, finally it was realized a comparison between the values gotten in the two done surveys and the confirmation of how much the UFPA would save in financial and energy terms with the biomass energy use. In conclusion the açaís seed is economically viable as energy resource for energy supply in UFPA, since the cost of supplied electric energy the concessionaire services the CELPA must exceed the cost of the renewable generation system, thus causing an economy in the final value, of the consumption of electric energy.
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    Influência da variação da razão de alimentação ar/serragem de um combustor ciclônico na composição dos seus produtos gasosos
    (Universidade Federal do Pará, 2008) VASCONCELOS, Adriano Akel; NOGUEIRA, Manoel Fernandes Martins; http://lattes.cnpq.br/2324813094737469
    In this work it was made an analysis of the combustion in a cyclonic combustor through experimental measures of the temperature and gases concentration in the internal wall of the combustion chamber. With the objective of finding an appropriate operational parameters for the proposed design, the feeding of air and sawdust of combustor was varied in a poor equivalence ratio (with excess of air) while the experimental data were computed. The data profiles obtained were confronted with the theory of the combustion of solids and with the temperature fields and gases concentration founded by Cunha (2005) numerically in the code Fluent V.6.0. In this comparison it was possible to find good qualitative value among the temperatures measured and the one from calculations, however there were differences in the topic concentration of gases. It was possible also to identify the minimum equivalence rate that the cyclonic combustor had in their gaseous products low pollutant tenors, like CO. Besides, at the end of this work a methodology was proposed to find the appropriate size of a cyclonic combustor in agreement with the strip of sawdust consumption that it wants to incinerate.
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    Metodologia de análise de risco de investimento em projetos de eficiência energética com aplicação no aproveitamento da biomassa residual do dendê na Amazônia
    (Universidade Federal do Pará, 2015-02-10) OLIVEIRA, Rosana Cavalcante de; TOSTES, Maria Emília de Lima; http://lattes.cnpq.br/4197618044519148
    The promotion of renewable energies in search of strategies to mitigate climate change is a major global challenge, especially for developing countries like Brazil looking to diversify its energy mix from renewable sources, but has an investment cost constraints. In this context, we need tools that measure the risks of investing in alternative energy sources projects. This work contributes to the sustainable development of the Amazon through the development of a risk analysis methodology of investment in energy efficiency projects applied the use of biomass from palm oil. The increasing production of palm oil in the Amazon region to generate food and biodiesel is generating a large volume of biomass. It was found that the use of the residue of the oil palm biomass for power generation and trading in the market increases its economic value, for both identified the criteria and indicators (C & I) of sustainable palm oil chain grouping them into: economic , environmental, social and technical. Qualifying and quantifying the risks affecting the identified indicators. This procedure was analyzed in three future scenarios for economic growth in Brazil that were built in the scenarios marked present in the National Energy Plan 2030.
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    Metodologia integrada utilizando sensoriamento remoto em redes neurais artificiais na quantificação do potencial de biomassa florestal na Amazônia
    (Universidade Federal do Pará, 2008-04-08) ALMEIDA, Arthur da Costa; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
    Pattern recognition and pattern classification in digital images is a very important skill, today. With them, it is possible to recognize and identify target objects in those images. This work proposes an integrated methodology for pattern recognition related to biomass in the Amazon tropical rainforest to extract information about bioenergetics potential for electric energy production for use with isolated Amazonian communities. To achieve this aim, information gathered about forest inventory was mixed with pattern classification and recognition in medium resolution satellite imagery such as those from LANDSAT and CBERS. The approach used in this work comes from the computational intelligence area, using artificial neural networks equipped with radial basis functions and Kohonen´s self organizing maps. The results serve as input to a geographical information system application which creates and manages a geographical database for energetic planning with renewable energy resources applicable to isolated Amazonian communities.
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    Um modelo de avaliação de fluxos de biomassa e carbono em madeireiras de comunidades isoladas da região amazônica
    (Universidade Federal do Pará, 2010-10-29) MARIALVA, Elden de Albuquerque; BRASIL, Augusto César de Mendonça; http://lattes.cnpq.br/0571960641751286; GUERRA, Danielle Regina da Silva; http://lattes.cnpq.br/6750321690921056
    The Amazon Region has a huge amount of biomass resources. The Brazilian Amazon comprises an area larger than 5 million km2, which represents 61% of the Brazilian territory. The Brazilian northern region produces 72.45% of the produced round wood in Brazil; the State of Pará shares 55.47% of that production. Generally, in Amazon region the lumbers get into the forest to select the logs to being cut. Some years later they return again to the same area to harvest again, and the interval time reduces each year. The Amazon region contained 833 sawmills in 1998. These sawmills were located mainly in the Amazon estuary (71%). These wood producers share 1.3 million cubic meters of wood logs (5% of production Amazon). The present work estimated the carbon balance of sawmills in the Amazon River estuary. A life cycle analysis was developed to estimate the carbon balance of the studied sawmills. The study was focused on the wood products considering the process used in small Amazonian communities. There is a well-defined path of the natural resource (biomass/wood) such as: forestry, transportation of biomass, transformation (business/timber) / processes, generation and use of wastes, transport of processed timber, marketing. The energy balance was also analyzed through the flow (inputs and outputs) of wood and carbon during the cycle. A numerical model was developed to simulate the flow of carbon, energy, wood and area affected by exploitation. This work developed a specific model for the evaluation of the carbon flow, the environmental impact assessment was reached, where it shown a positive value, a carbon capture about 55 tCO2/month, even with a low production efficiency system, around 36%. The results show that the current operating system does not pollute but could be improved to achieve higher efficiency in the production process. The waste generated was approximately 64% of the volume of wood entering the mill, its application could be managed to generate approximately 1240 kilowatts of electricity monthly.
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    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.
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    Obtenção de açúcares fermentescíveis a partir da casca de andiroba (carapa guianensis aubl.): estudo do pré-tratamento alcalino e avaliação cinética
    (Universidade Federal do Pará, 2020-01-24) SOUZA, Leiliane do Socorro Sodré de; QUARESMA, João Nazareno Nonato; http://lattes.cnpq.br/7826389991864785; https://orcid.org/0000-0001-9365-7498
    Neste trabalho, as cascas das sementes de andiroba foram submetidas a pré- tratamento alcalino, visando maximizar a recuperação dos açúcares redutores, avaliando o melhor desempenho de operação através das variáveis, tempo de reação (20, 60 e 100 min), concentração de NaOH (2, 3 e 4% (m/v)) e temperatura (60, 90 e 120ºC), em concentração de sólidos fixa, de 5% (m/v). Foi utilizado o planejamento experimental de Box-Behnken (15 ensaios). A biomassa pré-tratada nos 15 experimentos, foi hidrolisada enzimaticamente, em condições idênticas, carga de sólidos (5%), carga enzimática (15 FPU/g de biomassa) e tempo de reação (48 horas). O material lignocelulósico foi caracterizado através das análises de celulose (36,96 %), hemicelulose (16,74 %), lignina (36,02 %), extrativos (7,49 %), umidade (9,21 %), e cinzas (1,53 %). A otimização foi realizada por meio da abordagem metodologia de superfície de resposta. O modelo forneceu um coeficiente de determinação (R2) de 0,96, para sacarificação e 0,97, para sólidos recuperados. As condições ótimas previstas para realizar o processo foram, tempo de reação = 100 min, concentração de NaOH = 4% (m/v), temperatura = 120ºC, que permitiram obter uma conversão em termos de açúcares redutores de 47,89 %. O material lignocelulósico pré-tratado nas melhores condições, foi avaliado morfologicamente, através das análises de Espectroscopia no Infravermelho com Transformada de Fourier (FTIR) e Microscopia Eletrônica de Varredura (MEV), onde foi possível observar a maior disponibilidade da fração celulósica. Através do pré-tratamento alcalino foi possível reduzir em 34,7 % a fração de lignina, e em 23,52 % a fração de hemicelulose. A biomassa tratada nas melhores condições determinadas através da análise estatística foi hidrolisada e a cinética de sacarificação foi acompanhada. O processo foi acompanhado por um período de 96 horas, e foi possível observar que o rendimento de 54,44 % foi alcançado para um tempo de 72 horas, após esse período não houve mais aumento significativo. Os resíduos gerados na etapa de tratamento alcalino (licor negro) e hidrólise enzimática (biomassa residual), foram caracterizados através de FTIR e análise termogravimétrica, respectivamente, o que permitiu observar a presença predominante de lignina no licor negro, e de celulose na biomassa residual. Estes resultados podem ser considerados satisfatórios no contexto da biomassa florestal e pode ser elevado em uma escala futura do laboratório para a escala piloto, com estudos sobre a etapa de hidrólise enzimática.
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    Predição do desempenho de gasificadores de biomassa utilizando equilíbrio químico
    (Universidade Federal do Pará, 2007-08-10) OLIVEIRA, Antônio Geraldo de Paula; NOGUEIRA, Manoel Fernandes Martins; http://lattes.cnpq.br/2324813094737469
    The gasification technology has been object of study of many researchers, especially those involved in power generation use biomass. This paper presents a simplified model for biomass gasification based on chemical equilibrium considerations. The model consists in the minimization of the Gibbs free energy of the produced gas, constrained by mass and energy balances for the system. Despite the simplicity of the model, its results are reliable in identifying the tendencies of the working parameters for the system. Biomass composition, gasification temperature (air supplied), moisture content, air temperature, and heat losses are parameters that may be varied in order to evaluate different operational points. Results obtained are compared to those found in real operation of gasification processes and they shown good agreement.
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    Propriedades Térmicas do (Bio)Butanol e a Fotocatálise do Grafeno com Trifenilamina Dopado com Metais para Geração de H2
    (Universidade Federal do Pará, 2019-01-10) MARTINS, Marcelo Gonçalves; CHAVES NETO, Antonio Maia de Jesus; http://lattes.cnpq.br/3507474637884699
    In this study, the optical properties and electronic structures of the transition metal-doped G-TPA using water as solvent were theoretically investigated in order to evaluate the efficiency in the production of photocatalytic hydrogen. 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 LANL2DZ base, applying the effective potentials method for the transition metals (Ni, Pt, Pd, Fe, Os). Through the DOS of each structure an increase of accessible states in the valence layer was observed, as well as the decrease of the gap for all 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. Another analysis carried out in the sense of energy generation was the evaluation of the thermodynamic potential of the butanol properties as complementary fuel or substitute for conventional fuels. For this, the Gaussian09W allied to the DFT was used again, but combined with the functional ones, hybrid B3LYP with the base set 6-311 ++ G (d, p) and 6-31 + G (d), G3 and G4 , in addition to the CBS / QB3 compounds. The simulations were carried out and the thermodynamic properties were found, such as: the specific molar heat at constant pressure, the enthalpy of formation and the entropy. All the properties were obtained between the temperatures 100K - 1500K and constant pressure of 1atm, in addition the enthalpies of combustion 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.
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    Simulação numérica da gaseificação de biomassa em leito fixo
    (Universidade Federal do Pará, 2011) ITAI, Yuu; MALICO, Isabel; BRASIL, Augusto César de Mendonça; http://lattes.cnpq.br/0571960641751286
    The objective of this study was to evaluate the potential of açaí seeds rejected after processing in Belém - Pará, in order to be used as a source of biomass for energy production by gasification. Elemental analysis results obtained in LABCAT - UNB on a dry basis were obtained with percentages of Carbon, 46.06% Hydrogen, 6.01%, Oxygen, 43.37% , Nitrogen 4.33%and Sulfur 0.08%. These values and other parameters obtained in an experimental study carried out by the studies of Santos (2011) and Cruz (2010), were used to perform a numerical simulation of the gasification process by means of a zero dimensional FORTRAN code developed specifically for this purpose. Variations of the influence of equivalence ratio and moisture content in the concentrations of CO, H2 and CH4 were compared with experimental results. A transient one-dimensional model developed by Hla (2004) was also analyzed. Using the application of a mechanism of two steps pyrolysis where the primary tar (or oxygenated) are initially formed and then cracked into secondary tar (or oil) and other combustible gases. Thus is revealed the complexity of physical and chemical processes that occur in the reactor by the use of energy and mass balance information and rates of chemical reaction of the recommendations and the physical transport processes. The computer model can predict the profile of the gas composition, temperature, primary and secondary tar along the longitudinal axis of the gasifier. Data results have been obtained from both models and after the phenomena behaviour was analyzed in comparison with the experimental data obtained by Santos (2011).
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    Spatial and temporal distribution in density and biomass of two Pseudodiaptomus species (Copepoda: Calanoida) in the Caeté river estuary (Amazon region - North of Brazil)
    (Instituto Internacional de Ecologia, 2006-05) MAGALHÃES, André Luiz Perez; COSTA, Rauquírio André Albuquerque Marinho da; PEREIRA, Luci Cajueiro Carneiro; RIBEIRO, Marcilenia de Jesus da Silva; LIANG, Tsui Hua
    Spatial and temporal density and biomass distribution of the planktonic copepods Pseudodiaptomus richardi and P. acutus along a salinity gradient were investigated in the Caeté River Estuary (North-Brazil) in June and December, 1998 (dry season) and in February and May, 1999 (rainy season). Copepod biomass was estimated using regression parameters based on the relation of dry weight and body length (prosome) of adult organisms. The Caeté River Estuary was characterized by high spatial and temporal variations in salinity (0.8-37.2). Exponential length-weight relationships were observed for both Pseudodiaptomus species. Density and biomass values oscillated between 0.28-46.18 ind. m-3 and 0.0022-0.3507 mg DW. m-3 for P. richardi; and between 0.01-17.02 ind. m-3 and 0.0005-0.7181 mg DW. m-3 for P. acutus. The results showed that the contribution of P. richardi for the secondary production in the Caeté River Estuary is more important in the limnetic zone than in other zones where euhaline-polyhaline regimes were predominant. However, it was not possible to observe a clear pattern of spatial and temporal distribution for P. acutus.
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    Variação temporal do fitoplâncton e dos parâmetros hidrológicos da zona de arrebentação da Ilha Canela (Bragança, Pará, Brasil)
    (Sociedade Botânica do Brasil, 2009-12) SOUSA, Eliane Brabo de; COSTA, Vanessa Bandeira da; PEREIRA, Luci Cajueiro Carneiro; COSTA, Rauquírio André Albuquerque Marinho da
    Seasonal and nyctemeral variations of the phytoplankton and hydrological parameters were studied at a fixed station (00º46'37.2"S-046º43'24.5"W) situated in Canela Island (Bragança-Pará) in September and December, 2004 and in March and June, 2005. Subsurface water samples were taken for qualitative and quantitative phytoplankton studies and to determine chlorophyll a concentrations. Simultaneously physical and chemical parameters were measured: salinity, temperature, pH, dissolved oxygen and percent of oxygen saturation. A total of 64 taxa belonging to Cyanophyta (one taxon), Bacillariophyta (54 taxa) and Dinophyta (nine taxa) were identified. Chlorophyll a concentrations ranged from 4.67 mg m-3 (dry season), to 5.44 mg m-3 (rainy season) and follow phytoplankton densities, which were higher during the rainy period (mean values of 1,870 x 103 cell L-1). Phytoflagellates quantitatively dominated the local phytoplanktonic community followed by diatoms. Dimeregramma minor and Skeletonema sp. were abundant and ve
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