PETROBRAS; FINEP / Este trabalho apresenta o desenvolvimento de um modelo de simulação do processo de produção do biodiesel adequado à realidade brasileira, a qual possui os óleos de soja e algodão como principais matérias-primas. Estes óleos puros ou em misturas são modelados neste trabalho segundo uma expansão da composição em ácidos graxos de cada óleo vegetal, considerando triglicerídeos idealizados com cadeias laterais diferenciadas. Estes compostos são caracterizados na simulação a partir de propriedades fundamentais, como o ponto de ebulição, peso molecular, densidade e temperatura, pressão e volume críticos. Algumas delas possuem valores tabelados, enquanto outras foram estimadas pelo método de contribuição de grupos de Ambrose. O modelo é capaz de estimar propriedades do combustível final, tais como densidade, viscosidade e índice de iodo. Estes resultados foram verificados com dados experimentais obtidos da literatura. Além disso, dois fluxogramas do processo de produção do biodiesel foram modelados em estado estacionário, segundo os equipamentos responsáveis pela purificação e recuperação do biodiesel. No primeiro caso, propõe-se uma lavagem com água e uma coluna de destilação a vácuo. No segundo caso, tem-se um tanque horizontal, que representa um decantador, e novamente uma coluna de destilação a vácuo. Nos dois casos, os reagentes são bombeados para um reator contínuo, onde ocorre a conversão em biodiesel e glicerol. Esta conversão foi abordada de duas maneiras: usando uma conversão fixa em 95% e outra com a utilização de dados cinéticos da literatura capazes de descrever a conversão em função da concentração de reagentes e da temperatura da reação. Os resultados obtidos mostram o rendimento do processo em massa de biodiesel produzido para diferentes composições de matéria-prima. A partir destes resultados uma análise econômica preliminar é apresentada. Além disso, uma análise da integração energética é apresentada para o fluxograma de processo do segundo caso. Usando a análise "pinch", os níveis de utilidades são calculados e uma rede de trocadores de calor é proposta. / This work presents a simulation model for a biodiesel processing plant that fits the Brazilian case which utilizes soybean and cottonseed oils as major feedstocks. These pure oils or blends are modeled in this work according to a fatty acid expansion for each vegetable oil by considering abstract triglycerides with differentiated side chains. These components are characterized in the simulation by fundamental properties such as boiling point, molecular weight, density and critical temperature, pressure and volume. Some of them have reference values in the literature while others were estimated by Ambrose's group contribution method. In addition, two process flowcharts were modeled in steady state by using two different equipments for biodiesel downstream processing. In the first case, water washing and vacuum distillation columns are proposed. In the second case, there is a horizontal tank that represents a decantation unit followed by a vacuum distillation column. In both cases, reagents are fed to a continuous reactor where biodiesel plus glycerol conversion occurs. This conversion was modeled by using two different approaches. The first one considers a 95% fixed conversion while the second one uses kinetic data to describe the conversion as a function of reagents' concentration and temperature. The obtained results show the process efficiency for different feedstock compositions which are then used to accomplish a preliminary economic analysis. In addition, a process integration analysis is presented for the second process flowchart by using the pinch analysis. In this case, utility levels are calculated and a heat exchanger network is proposed.

Atualmente o interesse no bio-óleo para geração de energia e para produção de insumos químicos vem crescendo. O bio-óleo produzido a partir da pirólise rápida de biomassa gera compostos químicos de grande valor agregado para indústria química. Os compostos orgânicos voláteis (COVs) provenientes do bio-óleo como metanol, etanol, acetona, ácido acético e furfural podem ser recuperados e comercializados. A determinação e a quantificação dos COVs são realizadas por cromatografia gasosa. No entanto, os COVs do bio-óleo não podem ser caracterizados diretamente por cromatografia gasosa, pois o bio-óleo é uma matriz complexa e necessita de várias etapas de preparação de amostra. Este problema pode ser diminuído aplicando a técnica de headspace de evaporação completa (HSEC), juntamente com a análise por cromatografia gasosa (CG). Este trabalho apresenta um método simples e rápido, com necessidade mínima de preparação de amostra, desenvolvido para caracterizar metanol, etanol, acetona, ácido acético e furfural em amostras de bio-óleo por HS/EC-CG/DIC. O método utiliza 4 µL de amostra de bio-óleo em um frasco de headspace (20 mL), o tempo de evaporação completa para os compostos foi atingido em 7 minutos a 90 °C. Os compostos foram detectados e quantificados com um detector de ionização de chama e curvas analíticas externas. Os resultados mostraram que o método pode ser aplicado para determinar os COVs do bio-óleo. Os limites de detecção variaram de 0,13 a 0,16 µg entre os compostos. O método mostrou uma excelente exatidão avaliada pelo teste de recuperação, onde os valores encontrados para o metanol, etanol, acetona e ácido acético foram respectivamente 100,9%, 99,2%, 92,8%, e 104,3%. A recuperação do furfural foi baixa, cerca de 74,3%, provavelmente devido à polimerização do composto com componentes fenólicos do bio-óleo. O composto orgânico volátil de maior concentração na amostra de bio-óleo foi o ácido acético com 11,13%, seguido de metanol com 0,39%, etanol 0,26%, acetona 0,04% e furfural 0,01%. / The current growing of bio-oil interest for power generation and production of chemical inputs does the bio-oil from the fast pyrolysis of biomass an interesting raw material for chemical compounds of great value. The volatile organic compounds (VOCs) of bio-oil as methanol, ethanol, acetone, acetic acid and furfural can be recovered and marketed. The determination and quantification of VOCs are performed by gas chromatography, but VOCs bio-oil cannot be characterized directly by gas chromatography, as the bio-oil is a complex matrix, and requires several sample preparation steps. This problem can be solved by full evaporation headspace (HS/FE) and gas chromatography (GC) analysis. This paper presents a simple and rapid method to characterize methanol, ethanol, acetone, acetic acid and furfural in samples of bio-oil by HS/FE-GC. The method uses 4 µL sample of bio-oil in a headspace vial (22 mL), the time for complete evaporation of the compounds was 7 minutes at 90 °C, and detection and quantification was performed by a flame ionization detector using external analytical curves. The results showed that the method can be applied for determining VOCs of bio-oil, detection limits ranged from 0.13 to 0.16 µg of the compounds. The method showed excellent accuracy with the following recoveries: methanol (100.9%), ethanol (99.2%), acetone (92.8%) and acetic acid (104.3%). Furfural recovery was low, about 74.3% and it was associated to polymerization with phenolic the compound of bio-oil. The major volatile organic compound was acetic acid with 11.13%, followed by methanol with 0.39%, 0.26% ethanol, 0.04% acetone and 0.01% furfural.

PETROBRAS; FINEP / Este trabalho apresenta o desenvolvimento de um modelo de simulação do processo de produção do biodiesel adequado à realidade brasileira, a qual possui os óleos de soja e algodão como principais matérias-primas. Estes óleos puros ou em misturas são modelados neste trabalho segundo uma expansão da composição em ácidos graxos de cada óleo vegetal, considerando triglicerídeos idealizados com cadeias laterais diferenciadas. Estes compostos são caracterizados na simulação a partir de propriedades fundamentais, como o ponto de ebulição, peso molecular, densidade e temperatura, pressão e volume críticos. Algumas delas possuem valores tabelados, enquanto outras foram estimadas pelo método de contribuição de grupos de Ambrose. O modelo é capaz de estimar propriedades do combustível final, tais como densidade, viscosidade e índice de iodo. Estes resultados foram verificados com dados experimentais obtidos da literatura. Além disso, dois fluxogramas do processo de produção do biodiesel foram modelados em estado estacionário, segundo os equipamentos responsáveis pela purificação e recuperação do biodiesel. No primeiro caso, propõe-se uma lavagem com água e uma coluna de destilação a vácuo. No segundo caso, tem-se um tanque horizontal, que representa um decantador, e novamente uma coluna de destilação a vácuo. Nos dois casos, os reagentes são bombeados para um reator contínuo, onde ocorre a conversão em biodiesel e glicerol. Esta conversão foi abordada de duas maneiras: usando uma conversão fixa em 95% e outra com a utilização de dados cinéticos da literatura capazes de descrever a conversão em função da concentração de reagentes e da temperatura da reação. Os resultados obtidos mostram o rendimento do processo em massa de biodiesel produzido para diferentes composições de matéria-prima. A partir destes resultados uma análise econômica preliminar é apresentada. Além disso, uma análise da integração energética é apresentada para o fluxograma de processo do segundo caso. Usando a análise "pinch", os níveis de utilidades são calculados e uma rede de trocadores de calor é proposta. / This work presents a simulation model for a biodiesel processing plant that fits the Brazilian case which utilizes soybean and cottonseed oils as major feedstocks. These pure oils or blends are modeled in this work according to a fatty acid expansion for each vegetable oil by considering abstract triglycerides with differentiated side chains. These components are characterized in the simulation by fundamental properties such as boiling point, molecular weight, density and critical temperature, pressure and volume. Some of them have reference values in the literature while others were estimated by Ambrose's group contribution method. In addition, two process flowcharts were modeled in steady state by using two different equipments for biodiesel downstream processing. In the first case, water washing and vacuum distillation columns are proposed. In the second case, there is a horizontal tank that represents a decantation unit followed by a vacuum distillation column. In both cases, reagents are fed to a continuous reactor where biodiesel plus glycerol conversion occurs. This conversion was modeled by using two different approaches. The first one considers a 95% fixed conversion while the second one uses kinetic data to describe the conversion as a function of reagents' concentration and temperature. The obtained results show the process efficiency for different feedstock compositions which are then used to accomplish a preliminary economic analysis. In addition, a process integration analysis is presented for the second process flowchart by using the pinch analysis. In this case, utility levels are calculated and a heat exchanger network is proposed.

The aim of this study was to evaluate the potential of Hancornia speciosa (known as mangaba in Brazil) seeds for the production of bio-oil, in order to minimize the pollution problems caused by the inappropriate disposal of this residue and add value to this material which poses an environmental risk. The study was divided into two parts: the characterization of the biomass (through elemental analysis (CHN), infrared spectroscopy (FTIR-ATR), thermogravimetry (TG), and the moisture, ash, protein, oil, fiber, cellulose, hemicellulose and lignin contents); and the characterization of the bio-oil (thermogravimetry, infrared spectroscopy and gas chromatography/mass spectrometry-CG/MS). The mangaba seeds had a moisture content of 7.78±0.03%, high quantities of carbon (58.07%) and oxygen (27.18%), a calorific value of 23.45 MJ kg-1 and contained ash (1.87±0.06%), oil (27.33±0.37%), protein (12.10±1.60%) fiber (11.98±0.46%), cellulose (17.07%), hemicellulose (22.57%) and lignin (10.16%). The thermogravimetric curve for the sample showed a mass loss of around 90% up to a temperature of 450 °C. In the pyrolysis experiments the variables included temperature (450 and 600 °C), sample mass (5 and 11 g) and prior heating (with or without). The best conditions for the bioproduction of the bio-oil were 600 °C, 11 g of seeds and prior heating of the furnace. The characterization of the samples by FTIR allowed the presence of functional groups such as phenols, alcohols, ketones, acids, alkanes, alkenes, amides, nitriles and esters to be identified. The CG/MS analysis confirmed the results obtained with the infrared spectroscopy, with carboxylic acids and hydrocarbonates (~ 90%) being qualitatively identified as the major components, besides the presence of other compounds such as furanes, phenols, nitriles, aldehydes, ketones, alcohols, esters and amides. / O presente trabalho teve como objetivo avaliar o aproveitamento das sementes de mangaba para a produção de bio-óleo, a fim de minimizar problemas de poluição devido à disposição inadequada dos resíduos e agregar valor a este passivo ambiental. O trabalho foi dividido em duas partes: caracterização da biomassa (análise elementar (CHN), espectroscopia de infravermelho (FTIR-ATR), termogravimetria (TG), teor de umidade, cinzas, proteínas, teor de óleo, fibras, celulose, hemicelulose e lignina) e caracterização do bio-óleo (termogravimetria, infravermelho e cromatografia gasosa/espectrometria de massas-GC/MS). As sementes de mangaba apresentaram teor de umidade de 7,78±0,03%, alta quantidade de carbono (58,07%) e oxigênio (27,18%), poder calorífico (23,45 MJ kg-1), teor de cinzas de 1,87±0,06%, teor de óleo 27,33±0,37%, proteínas 12,10±1,60%, fibras 11,98±0,46%, celulose (17,07%), hemicelulose (22,57%) e lignina (10,16%). A curva termogravimétrica da amostra apresentou cerca de 90% de perda de massa até a temperatura de 450 °C. Os experimentos de pirólise incluíram como variável temperatura (450 e 600 °C), massa de amostra (5 e 11 g), com ou sem aquecimento prévio. A melhor condição para a produção de bio-óleo foi a 600 °C, 11g de semente e com aquecimento prévio do forno. Através da caracterização da amostra em FTIR foi possível identificar a presença de grupos funcionais como fenóis, alcoóis, cetonas, ácidos, alcanos, alcenos, amidas, nitrilas e ésteres. Por outro lado, as análises de GC/MS confirmaram os resultados obtidos com o infravermelho, sendo identificados qualitativamente os ácidos carboxílicos e hidrocarbonetos (~ 90%) como componentes majoritários, além de serem encontrados outros compostos como furanos, fenóis, nitrilas, aldeídos, cetonas, alcoóis, ésteres e amidas.

Dentre as constantes alterações climáticas que vem ocorrendo ao longo dos tempos, seguramente a que mais preocupa o homem é alteração da temperatura ambiente, provocada principalmente pelo aumento demasiado do consumo de combustíveis fósseis e o desmatamento de florestas nativas, que no Brasil é bastante evidente. Estas práticas influenciam o regime de chuvas e comprometem diretamente a qualidade de vida na Terra. Apesar da água ser fundamental para a manutenção da vida do ser humano, no Brasil, a falta dela causa uma preocupação ainda maior, que é a diminuição da oferta de energia elétrica, uma vez que 70% da geração deste tipo de energia provêm de hidrelétricas. Daí a preocupação cada vez maior em buscar processos mais eficientes do ponto de vista de consumo de energia elétrica. Dentro deste contexto, o objetivo geral deste trabalho foi evidenciar a possibilidade de ganhos energéticos através da recuperação de energia no ambiente industrial. O trabalho foi realizado em um frigorífico abatedouro de frangos de uma grande empresa de alimentos, que consome em seus processos uma quantidade de energia muito alta e em várias formas. Dos energéticos utilizados neste tipo de indústria, tem-se vapor como um dos insumos mais importantes, sendo gerado em grandes quantidades. Embora, no processo analisado não haja a necessidade de vapor em nenhuma das etapas de beneficiamento do produto final. Neste trabalho é mostrado como o vapor é utilizado no frigorífico estudado, qual a sua finalidade e por que há atualmente, uma dependência tão forte deste recurso. São apresentadas alternativas que foram encontradas para substituição completa deste insumo energético. O trabalho mostrou as alternativas de recuperação de energia e o impulso positivo gerado para obtenção do objetivo principal. Um aquecedor de água utilizando combustível misto (cavaco de madeira misturado a uma porção de 10% em massa de lodo centrifugado de estação de tratamento de efluente da empresa) é proposto, sendo identificado um retorno dos investimentos previstos em 3 anos e 7 meses a uma taxa de financiamento de 14% ao ano. O projeto garantiu o abastecimento de água quente sem a utilização de vapor, a um custo menor, e ainda obteve ganhos ambientais relevantes, que foi a redução de 23,7% no consumo de biomassa, e a utilização no aquecedor de 60 toneladas por mês de material rejeitado do processo industrial. / From among the constants climatic changes that has been occurring throughout the ages, undoubtedly the what worries man is temperature variation, caused mainly by the increase far too consumption of fossil fuels and deforestation of native forests, which in Brazil is quite evident. These practices influence the rainfall and directly affect the quality of life on Earth. Although water is essential for the maintenance of human life, in Brazil, the lack of water brings an even greater concern, which is the reduction of electricity supply, because 70% of the generation this type of energy are derived from hydropower. Hence, the growing concern in seeking more efficient processes from the point of sight of energy consumption. In this context, the objective of this work is to demonstrate the possibility energy saving through energy recovery in the industry. The study was conducted in a poultry slaughterhouse of a large food company that uses in its processes a very high amount of energy and in various forms. The energetic used in this type of industry, it has been steam as a major input, being generated in large quantities. Although, the analyzed process there is no need to steam in any of the manufacture steps of the final product. In this work it is shown as the steam is used in the slaughterhouse studied, for what purpose and why there is currently so strong dependence on this resource. Presented are alternatives that have been found for complete replacement of this energy input. The work showed the alternatives of energy recovery and the positive impulse generated to obtain the main objective. A water heater using mixed fuel (wood chip mixed with a 10% by mass portion of dried sludge from the company's effluent treatment plant) is proposed, with a return on investment of 3 years and 7 months at a financing rate of 14% per year. The project guaranteed the supply of hot water without the use of steam, at a lower cost, and also obtained significant environmental gains, which was the reduction of 23.7% in biomass consumption, and the use in the heater of 60 tons of material rejected from the industrial process.

Orientador: Arnaldo Cesar da Silva Walter / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-14T09:14:27Z (GMT). No. of bitstreams: 1 Silva_CinthiaRubioUrbanoda_M.pdf: 1044299 bytes, checksum: 00aea84fe56180f6398b263bf1ad7fe0 (MD5) Previous issue date: 2009 / Resumo: A busca por combustíveis que substituam fontes fósseis tem incentivado a produção de biocombustíveis, especialmente para o setor de transporte. O objetivo deste trabalho é fazer os balanços de energia e das emissões de gases de efeito estufa do etanol derivado da cana de açúcar produzido no Brasil. Na dissertação, foram também avaliadas as emissões de gases de efeito estufa associadas à mudança do uso do solo devido à expansão de áreas cultivadas com cana (impacto direto), bem como os fatores relacionados à distribuição do etanol para uso no Brasil e na Europa. Um cenário de uso do etanol em substituição ao biodiesel (B3) nas etapas de transporte da cana e distribuição do etanol é igualmente analisado. Os balanços abrangem as etapas de produção da cana de açúcar, transporte até as usinas, produção, distribuição e uso final do etanol anidro. A análise é realizada separadamente para cada estado brasileiro da região Centro-Sul que tem significativa produção de etanol (Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais, São Paulo e Paraná). A base de dados, obtida na literatura, reflete as condições de produção no Brasil no período de 2005 a 2007. Os resultados apontam balanços favoráveis para o etanol quando usado no Brasil. Para a produção no Brasil e uso na Europa, os balanços resultaram menos favoráveis. Quando o uso do etanol passa a ser feito em substituição ao B3, os balanços são significativamente mais positivos. Os resultados levam à conclusão de que melhores balanços de energia e das emissões de gases de efeito estufa dependem basicamente do modal de transporte para distribuição do etanol, práticas agrícolas adotadas (plantio direto ou convencional) tanto para produção da cana quanto da biomassa que foi substituída, método para cálculo das emissões de óxido nitroso associadas à aplicação de fertilizantes nitrogenados, além das produtividades agrícolas e industriais. / Abstract: The search for fuels that replace fossil resources have stimulated biofuel production, especially for the transportation sector. The goal of this work is to do balances of energy and of greenhouse gas emission of ethanol from sugar cane produced in Brazil. In this dissertation, greenhouse gas emission associate to land use change due to expansion of areas cultivated with sugar cane (direct impact), as well as how the factors related to distribution of ethanol for use in Brazil and for use in Europe, were also evaluated. Scenery of ethanol use in replace to biodi esel(B3) in the transportation of sugar cane and distribution of ethanol stages is equally ana lyzed.The balances embrace the stages of the sugar cane production, transportation until the mill, production, distribution and end use of the anhydrous ethanol. The analysis is done separately for each Brazilian State of the Centre-South region that has great ethanol production (Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais, São Paulo and Paraná). The data base, achieved in literature, reflects the conditions Brazilians of production in the period from 2005 to 2007. The results show favorable balances for the ethanol when it is used in Brazil. In the case of production in Brazil and consumption in Europe, the balances resulted less favorable. When the ethanol use starts to be done in replace to B3, the balances are remarkably more positive. The results lead to the conclusion that better energy and greenhouse emission balance depend basically on: i) the means of transportation to distribute the ethanol; ii) agricultural management adopted (direct or conventional planting) as for sugar cane production as for biomass production that was replaced; iii) the method to calculate the nitrous oxide emission from application of fertilizer with nitrogen, besides agricultural and industrial productions. / Mestrado / Planejamento de Sistemas Energeticos / Mestre em Planejamento de Sistemas Energéticos

Orientador: Antonio Carlos de Oliveira Ferraz / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-09T08:28:04Z (GMT). No. of bitstreams: 1 Palermo_EvaldoLuiz_M.pdf: 4467095 bytes, checksum: e69d9929bffdc155a4086ae81051acc7 (MD5) Previous issue date: 1998 / Resumo: O palhiço da cana-de-açúcar, em função da sua produção em grande escala, e a atual situação energética do Brasil, tem sido considerada como uma importante fonte alternativa para minimizar a crise energética. Todavia se conhece pouco das suas propriedades mecânicas e dos parâmetros de enfardamento os quais podem melhorar a eficiência das operações de manuseio da palha. O trabalho foi elaborado com a finalidade de estudar o comportamento mecânico do palhiço da cana-de-açúcar em ensaios de compressão e relaxação, realizados em laboratório com a máquina de ensaio MTS empregando taxas de deformação de 10 mm/s, 20 mm/s, 30 mm/s, 40 mm/s e 43 mm/s. E, em campo, através da utilização da enfardadora prismática Nogueira AP 41N, devidamente instrumentada para registrar o sinal da força atuante na biela e a rotação da manivela de acionamento. A partir dos ensaios de compressão foram analisadas as curvas pressão versus densidade aparente, bem como uma avaliação do consumo energético e analise das curvas de relaxação em função das condições de ensaio adotadas. No ensaio com a enfardadora foi determinada a força axial média atuante na biela de 800 kgf, obtendo fardos com densidade média de 250 kg/m3. O grau de umidade apresentou influência na relação pressão x densidade, bem como na energia específica necessária para compactar as amostras. O aumento do grau de umidade diminui a pressão necessária para acondicionar o palhiço no interior do cilindro de compactação e, em conseqüência, diminui a energia específica consumida para compactar o material / Abstract: Mostly because of its large scale production in Brazil, sugar cane straw has been considered an important alternative biomass source to cope with present energy shortage. However very little is know about its mechanical properties and baling parameters witch would improve straw handling operations. In this investigation mechanical parameters of the straw were obtained in laboratory conditions using compression and relaxation tests at several strain rates such as 10 mm/s, 20 mm/s, 30 mm/s, 40 mm/s and 43 mm/s. Field tests were performed using a commercial rectangular baler (Nogueira AP 41N), properly instrumented to register cranck force and drive wheel rotation speed. From the compression tests results the pressure-density curves were plotted and analysed. Energy comsumption and relaxation curves were also obtained for several moisture levels and strain rate conditions. The mean value obtaind during field tests with the commercial baler for the crank force was 800 kgf which produced bales with mean density of 250 kg/m3. Moisture content influenced the pressure-density relations as well as the specifc energy needed to compress the samples. Higher moisture content reduces compression force and consequently the total energy needed in the compression process / Mestrado / Maquinas Agricolas / Mestre em Engenharia Agrícola

O setor florestal apresenta grande importância econômica no Brasil, representando uma significativa parcela no PIB, nas exportações e na geração de empregos. As florestas fornecem matéria prima para a produção de energia ou celulose e são avaliadas, normalmente, por um enfoque econômico, que, isoladamente, não traz a sustentabilidade do setor. Para se avaliar a sustentabilidade, análises sistêmicas e de fluxo de material são algumas das alternativas. O fluxo de material fornece subsídios às metodologias que abordam os diversos aspectos da sustentabilidade, como por exemplo, a análise de energia, a síntese de emergia e análises integradas de aspectos sociais, econômicos e ambientais. Tendo em vista a importância da área florestal e a falta de estudos que permitam uma avaliação sistêmica dessa atividade, esse trabalho teve por objetivo avaliar a sustentabilidade energética de um sistema de produção. Para tanto, elaborou-se um modelo para determinar o fluxo de material, referente aos insumos utilizados indiretamente nas operações mecanizadas do sistema de produção: mão-de-obra, combustível e depreciação material do maquinário. Através desse modelo avaliou-se o cenário básico, que utiliza calcário na correção da acidez do solo e suas alternativas: cinzas e biossólido. Com base nesses resultados, avaliou-se o sistema através da análise de energia e da síntese de emergia. A análise de energia aborda os fluxos energéticos dos insumos aplicados e o dos produtos obtidos, possibilitando a determinação da lucratividade energética (EROI), o ganho líquido (balanço de energia) e a intensidade energética do sistema de produção. A síntese de emergia contempla os recursos naturais renováveis e os não-renováveis, além dos recursos adquiridos no mercado. Essa análise e síntese estabeleceram os fluxos de recursos, identificando seus principais fatores de produção e os indicadores que têm potencial de uso na tomada de decisão de empresas florestais. Utilizou-se da análise de sensibilidade para avaliar o efeito dos fatores de produção na sustentabilidade do sistema. Os resultados obtidos mostraram que o sistema de produção apresenta uma maior sustentabilidade energética quando comparado com os sistemas de produção menos intensificados. Para a análise de energia, o combustível foi o fator com maior participação na energia de entrada, com os fertilizantes e herbicidas na sequência. Na síntese de emergia, um recurso renovável, evapotranspiração, foi o principal fator. Quando considerou-se os fatores exógenos ao sistema na síntese, o combustível, os fertilizantes e os corretores de acidez foram os principais. Nas duas metodologias, a colheita foi a operação mais demandante de recursos e as alternativas ao calcário pioraram o desempenho energético do sistema. Ressalta-se que as avaliações dessas alternativas não consideraram os benefícios indiretos em não se descartar os resíduos utilizados no ambiente, indicando um caminho para novos estudos. Para se elevar a sustentabilidade, deve-se melhorar a eficiência da colheita e reduzir o uso de insumos com menor redução proporcional da produtividade. Ambas as metodologias deveriam ser consideradas na avaliação de sistemas produtivos, pois tratam de uso de recursos ambientais e exógenos e quantificam a intensidade energética dos produtos, permitindo comparações. / The forestry sector is very important to the Brazilian economy, representing a significant share of the GDP, exports and employment generation. Forests supply raw material for energy and cellulose production and are usually evaluated through an economical approach, which, alone, does not reflect the sustainability of the sector. In order to evaluate sustainability, system and material flow analyses are some alternatives. The material flow gives subsidy to methodologies that approach the several aspects of sustainability, such as, energy analysis, emergy synthesis and analysis integrating social, economic and environmental aspects. Due to the importance of the forestry sector, the lack of studies that systemically evaluate this activity, this study aimed to evaluate the energetic sustainability of a production system. So, one elaborated a model to determine the material flow, regarding the inputs indirectly applied in the mechanized operations in the production system: labor, fuel and material depreciation of machinery. This model evaluated the basic scenario, which uses lime to control soil acidity, and its alternatives: ashes and sludge. Based on the obtained results, the system was evaluated through energy analysis and emergy synthesis. The energy analysis approaches the energy flows of the applied inputs and the obtained products, propitiating the determination of the energetic profitability (EROI), the net gain (energy balance) and the energetic intensity of the production system. The emergy synthesis ranges the renewable and non-renewable natural resources, besides those acquired in the market. This analysis and this synthesis establish the resource flows and identified the main production factors and present indicators with potential use in the decision making of forestry enterprises. The sensitivity analysis evaluated the effect of the production factors in the system's sustainability. The obtained results showed that the studied production system presents higher energetic sustainability than some systems with less intensification. In the energy analysis, fuel was the main factor in the energy input, followed by fertilizers and herbicides. In the emergy synthesis, evapotranspiration, a renewable resource, was the main factor. Considering the factors exogenous to the system, fuel, fertilizers and soil acidity correctors were the main ones. In both methodologies, harvesting was the more demanding operation and the alternatives to liming decreased the energetic performance of the system. One should highlight that in the evaluating of both alternatives, no indirect benefit was considered, such as the avoidance of dumping those materials. This indicates new possibilities of studies. In order to increase sustainability, one should improve the harvest efficiency and reduce use of the agricultural inputs with less proportional reduction of the yield. Both methodologies should de considered in the evaluation of productive systems since they approach the use of environmental and exogenous resources; they quantify the intensity of products and allow comparisons among systems.

Cette thèse porte sur le développement d'une approche de modélisation destinée à quantifier la durabilité de systèmes industriels à partir de biomasse (considérés comme des systèmes complexes), et à fournir un outil d’aide à la décision qui permette, en modifiant certaines de leurs caractéristiques, de diminuer leurs impacts environnementaux.Elle s’appuie sur deux études de cas régionales : la première permet de tester l’hypothèse théorique pour évaluer les facteurs qui contribuent à l’adoption par les agriculteurs du « panic érigé » (switchgrass) dans l’Etat du Michigan (USA), et les effets associés en termes d’impacts environnementaux, en utilisant un modèle multi-agents couplé à l’analyse du cycle de vie ; la seconde combine modélisation multi-agents et système d'information géographique par le biais d’une analyse de flux de matières et d’énergie pour révéler les opportunités symbiotiques d’un écosystème agro-industriel en Champagne-Ardenne (France).On montre que ces deux modèles fonctionnels ont une valeur ajoutée significative pour l’analyse de systèmes sociotechniques durables et la simulation de scénarios futurs / This research is about developing a modeling framework in order to quantify the sustainability of industrial systems for biomass energy (conceived of as complex systems), and to provide decisionmakers with an aiding-tool for reducing their environmental impacts by modifying some of their features.It draws upon two regional case-studies. In the first one, an hybrid agent-based/life cycle assessment approach is used to test the theoretical background, understand the main decision-making factors influencing farmers’ adoption of switchgrass ethanol in Michigan (USA) and assess how such patterns affect environmental impacts. In the second case-study, agent-based modeling and geographical information system are used together via material and energy flow analysis to reveal the potential for industrial symbiosis in the bio-economy cluster of Champagne-Ardenne (France). We show that both models have a significant added value for the analysis of sustainable complex systems and the simulation of future scenarios

Energy is an important input for various activities that provide impetus to economic, human and social development of any country. Among all the energy carriers, electricity is the most important and sought after energy carrier for its quality, versatility and ability to perform various technology driven end-use activities. Therefore access to electricity is considered as the single most important indicator determining the energy poverty levels prevailing in a country. Demand for electricity has increased significantly, especially in the developing countries, in recent years due to growth in population and intensification of economic activities. Therefore, providing quality and reliable electricity supply at low-cost has become one of the most pressing challenges facing the developing world. Although sufficient efforts have gone into addressing this issue, little progress has been made in finding a satisfactory solution in alleviating this problem. Currently, electricity supply is mostly dependent on centralized large-scale power generation. These centralized systems are strongly supply focused, fossil-fuel intensive, capital intensive, and rely on large-distance transmission and distribution systems. This results in electricity cost becoming unaffordable to the majority poor which comprises more than 70% of the total population in developing countries like India and the benefits of quality energy remaining with the rich, giving rise to inequitable distribution of energy. Continuous exploitation of fossil fuels has also contributed to local and global pollution. Therefore it is necessary to explore alternate means of providing energy access such that the energy carriers are clean, easy to use, environmentally benign and affordable to the majority of the rural poor. India is at a critical juncture of passing through the path of development. India is also in a unique position that its vast majority of rural population is energy poor which is disconnected from the electricity grid. In this context, the proposed research is an attempt towards developing a greater understanding on the issue of rural energy access and providing a possible solution for addressing this gap. This has been proposed to be achieved by adopting a decentralized energy planning approach and distributed energy systems mostly based on renewable energy sources. This is expected to reduce dependence on imported energy, promote self-reliance, provide economically viable energy services for rural applications and be environmentally safe. The focus is limited to biomass energy route which has many advantages; it is a geographically equitably distributed resource, geographical advantage of having potential to setup energy systems at any location where vegetation is present and not seasonal like other renewable energy technologies. A mathematical model-based approach is developed to assess the feasibility of such a proposal. Models are developed for performing biomass resource assessment, estimating end-use-wise hourly demand for electricity, performing capacity and location planning and assessing economic feasibility. This methodological framework was validated through a case study developed for the district of Tumkur in the state of Karnataka (a state in southern region of India). The literature survey was conducted exhaustively covering the whole span of supplyside and demand-side management of electricity systems, and grid-connected and stand-alone power generation systems, their technical, economic and environmental feasibilities. Literature pertinent to GIS applications in biomass assessment, facility location planning and scheduling models were also reviewed to discern how optimal capacity, location and economic dispatch strategy was formulated. Through the literature survey it was understood that there were very few attempts to integrate both demand-side management and supply-side management aspects in the rural energy context. GIS based mathematical models were sparsely used in rural energy planning and decision making. The current research is an attempt to bridge these gaps. The focus in this study is on effectively utilizing the locally available biomass resource. Assessment of Biomass Potential for Power Generation As a first step, the supply option was studied at village level by overlaying LULC (land use land cover) and village boundary GIS maps of Tumkur district. The result was fortified by the NDVI results from remote sensing images of land use pattern in Tumkur district. A detailed village-level assessment of wasteland potential was made for the entire district. The result showed which shows that in Tumkur district, roughly 17.3% of total geographical land was under exploitable wasteland. Using secondary data and literature, biomass potential indices were prepared for different wasteland types to determine the total biomass potential for power generation. The results based on the GIS data the assessment shows that Tumkur has roughly 17.3% of exploitable wasteland. A complete village-level annual power generation potential was assessed considering both energy plantations from wasteland, existing degraded forests and crop residues. Assessment of end-use-wise hourly Demand for Electricity at Village Level Household survey was conducted for 170 sample households randomly chosen from 15 villages, again randomly selected to represent different socio-economic categories. Using statistical tools like k-means clustering, one-way ANOVA and Tukey’s HSD test, first the households were classified into three economic categories to study the distribution of the households in each sample village. Later based on the number of households of each type in a village, the villages were further classified into five groups based on their socio-economic status. This was done to select the right representative per-household power demand for a village of any particular socioeconomic category. The representative per household power demand in each economic category along with secondary data helped in deriving the electricity daily load profiles for all the villages. Representative demand profiles were generated for different seasons across different sectors namely domestic, agriculture and industry sectors at the end-use level comprising of activities like home lighting, appliances, irrigation pump sets operation and small industry operations. Mathematical Modeling for Optimal Siting of Biomass Energy Systems Since the power has to be generated through biomass route, biomass may have to be transported over a large geographical area which requires efficient design of logistic systems. Apart from that, a major component of cost of biomass power is the cost of transportation of biomass from source to the power plant. Therefore it is important to determine the optimal siting of biomass energy systems to minimize the cost of transportation. Since these optimal locations are based on minimizing Euclidian distance, installing the power generation systems at these locations would also minimize total cost of local transmission and distribution. In order to locate the biomass energy system, K-medoid clustering algorithm was used to determine the optimal number of clusters of villages to minimize the Euclidean distance between the medoid of the cluster and the villages within the cluster, and minimize the total installed capacity to meet the cluster demand. The clustering algorithm was modified in such a way that the total capital cost of the power generation system installation was minimized. Since the total project cost not only depended on capital cost alone, but also on biomass transportation and power transmission costs, these costs were also included in the analysis. It was proposed to locate the energy systems at the medoids of the clusters. Optimal Capacity Planning Installing biomass power systems requires large investments. It is therefore necessary to reduce the peak demand to bring down the installed capacity required. This was achieved by developing heuristics to arrive at an optimal scheduling scheme of the end-use activities that would minimize the peak demand. The heuristics procedure was demonstrated on five representative villages, each from different economic category. The optimal demand profile was used as input in HOMER micro-energy system simulation software to perform a techno-economic analysis. The simulation facilitated a thorough economic feasibility study of the system. This included a complete analysis of the cash inflows and outflows, capital cost of the system, operation and maintenance cost, cost of fuel and estimation of total GHG emissions. There are many limitations in planning at village-scale. The results indicated that capacity planning done at the village level was prone to over-estimation of installed capacity of the system increasing the investment requirement, under utilization of the capacity and suffered from supply scarcity of biomass. This emphasized the need for looking at a bigger conglomerate of villages in other words cluster of villages. In the next step, the optimal capacity planning was performed for one of the clusters formed using the K-medoid clustering algorithm with the power generation system located at the medoid. For demonstrating the practical feasibility of extending the methodology to cluster level, a cluster with maximum number of villages was chosen from the optimal cluster set in the k-medoid algorithm output. The planning was conducted according to the socioconomic category of the villages in the cluster. Economic implications of Stand-alone (SA) vs Grid-connected (GC) Mode of Operation Other important question that was answered in this analysis was a comparison of GC systems with SA systems. Since extension of grid to a village that is not electrified involved drawing high voltage transmission lines from the nearest grid point, installation of distribution transformers and low transmission lines within the village for distribution. Since these involve high costs it was necessary to study whether or not it is feasible to extend the grid or install a stand-alone system. This question was answered by the breakeven distance for which grid extension becomes more economical than a SA system. For each village breakeven distance varied with the total installed capacity and the operational costs. This helped to compare the GC systems vis-à-vis SA systems from the point of view of economic feasibility. Summary It is necessary that planning and strategies be rational and reasonable for effectively assuaging the rural electrification imbroglio. The current study has highlighted the importance of integrating both demand-side-management and supply-sidemanagement of energy systems in the context of planning for power generation and distribution in rural areas. The key findings in the current study are: • The study showed the feasibility of biomass power systems in meeting the rural electricity needs. • Biomass assessment results showed that, if the power demand could be brought down by replacing the existing appliances with efficient ones (ex. compact fluorescent lamps and improved irrigation pump set valves), Tumkur district has enough biomass potential to meet both the current as well as increased future demands for electricity. • The optimal number of clusters minimizing total capital cost of biomass energy systems, transportation cost of biomass and distribution cost of power, was 96 for Tumkur district. For Kunigal block, the optimal number of clusters was 37 and 32 for supply and demand scenarios 1(BAU -Business As Usual) and 2 (with 10% increase in cropland and 20% increase in demand). • The optimal capacity planning emphasized the importance of clustering of villages for minimizing the total installed capacity. The result also showed that the breakeven distance was the determining factor about the choice of GC vs SA systems. The main contributions of this thesis are: i. Hourly demand pattern was studied to estimate the aggregate demand for electricity at village level for different sectors across various seasons. ii. Village-wise biomass resources potential for power generation was assessed iii. Optimal locations for siting biomass energy systems were identified using k-medoid clustering algorithm iv. An optimal scheduling of end-use activities was planned using heuristics method to minimize the installed capacity v. Optimal location, scheduling plan of end-use activities and optimal capacity were determined for individual villages as well as village clusters vi. The economic implications of grid extension vis-à-vis stand-alone mode of operation of the installed biomass energy systems were studied The generalized, multipronged approach presented in this thesis to effectively integrate both demand-side management and supply-side management in rural energy planning can be implemented for any rural region irrespective of the location. The results emphasized that for efficient demand-side and supply-side management, it is important to plan for clusters of villages than at the individual village level. The results reported in this thesis will help the policy and strategy makers, and governments to achieve rural electrification to a satisfactory extent to ensure continuous, uninterrupted and reliable power supply by determining the clustering strategy, optimal cluster size, optimal scale and siting of decentralized biomass power generation systems.