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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Anaerobic Biodegradation Patterns for Biodiesel

Wu, Shuyun January 2014 (has links)
No description available.
2

Aerobic Biodegradation Kinetics, Aquatic Toxicity and Paritioning, and Microbial Community Structures of Petrodiesel/Biodiesel Blends

Yassine, Mohamad H. 20 April 2012 (has links)
No description available.
3

Análise de ecoeficiência: avaliação do desempenho econômico-ambiental do biodiesel e petrodiesel. / Eco-efficiency analysis: environmental-economic assessment of biodiesel and petrodiesel.

Fernanda Cristina Vianna 21 July 2006 (has links)
O biodiesel é a mais provável alternativa ao petrodiesel. É constituído de uma mistura de ésteres metílicos ou etílicos de ácidos graxos, obtidos da reação de transesterificação entre qualquer triglicerídio e um álcool de cadeia curta, metanol ou etanol. Possui praticamente as mesmas propriedades do petrodiesel, mas comparado a este, pode eliminar as emissões de óxido de enxofre e reduzir as emissões de CO2. O Brasil vem sendo apontado como futuro líder na produção de biodiesel, devido às suas excelentes condições de clima, solo, e imensa extensão territorial, que são propícias para a plantação de diversas oleaginosas. Com tantas especulações, o governo federal brasileiro criou o Programa Nacional de Produção e Uso de Biodiesel (PNPB), visando a implementação da produção e uso do biodiesel de forma sustentável. Para tanto, uma lei federal foi promulgada em 2005, estabelecendo a adição de 5% de biodiesel ao petrodiesel vendido ao consumidor final. Esta lei deve ser implementada em um período de 5 anos, nos quais as empresas produtoras devem começar usando um mínimo de 2% em um período de 3 anos. Este trabalho apresenta uma avaliação econômica-ambiental comparativa entre biodiesel (de óleo de palma e etanol) e petrodiesel para as condições brasileiras, usando a Análise de Ecoeficiência desenvolvida pela BASF. Esta análise pertence a uma classe de técnicas da gestão ambiental que visa avaliar o desempenho ambiental de produtos, processos e serviços, de forma integrada a uma avaliação econômica. Esta classe de técnicas é usada, principalmente, para a comparação de produtos similares e de processos que executem uma mesma função, visando à geração de subsídios para a tomada de decisão em diversos níveis. Esta metodologia considera um indicador ambiental baseado em um inventário de ciclo de vida associado a uma avaliação simplificada de riscos de acidentes à saúde humana, os quais são classificados de acordo com a severidade das conseqüências e probabilidade de ocorrência e; um indicador econômico, calculado a partir dos custos do ciclo de vida do produto. No que diz respeito à avaliação do biodiesel, para os dados relativos ao óleo de dendê (ou palma), utilizaram-se dados de campo, obtidos junto ao Grupo Agropalma, maior produtor nacional do óleo e, no que diz respeito ao etanol foram utilizadas fontes secundárias, ou seja, dados disponíveis em literatura. Outros dados e informações relacionados mais especificamente com a produção do biodiesel foram adquiridos de literatura e levantados junto a especialistas e responsáveis pela tecnologia de produção do mesmo. Com relação ao petrodiesel, os dados foram obtidos de base de dados internacionais e, posteriormente, adaptados à realidade brasileira, por meio de informações obtidas junto à Petrobras e à literatura especializada. As informações relacionadas ao petrodiesel foram levantadas para 26 litros de combustível e, as referentes ao biodiesel para 30 litros. Estas quantidades foram determinadas considerando-se o quanto de produto faz-se necessário para a geração de 1.000 MJ de energia em motores de combustão interna. Os dados foram coletados para as etapas de extração dos recursos e transformação dos mesmos, não sendo consideradas as etapas de distribuição, uso e disposição final.Como resultado, tem-se o biodiesel como opção mais ecoeficiente. O grande diferencial entre as duas alternativas é o desempenho ambiental do biodiesel, fato esse, justificado principalmente, pelo reduzido consumo de recursos materiais e a baixa toxicidade do produto, pois as matérias-primas necessárias para sua formação (o etanol e o óleo de dendê) têm caráter renovável e, durante a produção do petrodiesel existe o contato com muitos hidrocarbonetos voláteis, algo que não ocorre com o biodiesel. Este estudo fornece informações que podem auxiliar na tomada de decisões sobre a consolidação do uso do biodiesel no Brasil, além disso, contribui com inventários do ciclo de vida, que podem auxiliar no desenvolvimento de um banco de dados de ACV (Avaliação do ciclo de vida) representativos da realidade brasileira. / Biodiesel is the most likely alternative to petrodiesel. It is composed of methyl or ethyl esters from fatty acids, obtained by a transesterification reaction between any triglycerides and an alcohol with short chain, methanol or ethanol. It has almost the same properties of petrodiesel, but comparing with this, it can eliminate the sulfur oxides emissions and significantly reduce the CO2 emissions. Brazil is being considered as a future leader in biodiesel production due to its excellent climate and soil condition and vast territorial extension conducive to a crop of varied oil plants. Around so many speculations, Brazilian federal government has created the National Biodiesel Production and Use Program (PNPB) aiming to the implementation of a sustainable biodiesel production and use. Focusing this issue, a federal law was promulgated in 2005 in order to establish the addition of 5% biodiesel to the petrodiesel sold to the ultimate consumer. This fact should be implemented within a 5 – year period in which companies should start using the minimum of 2% biodiesel within a 3 – year period. This paper presents an environmental and economic comparison between biodiesel (from palm oil and ethanol) and petrodiesel regarding Brazilian conditions, according to the Eco-Efficiency Analysis developed by BASF. This analysis belongs to a class of techniques of the environmental management, which aims to evaluate the environmental performance of products, processes and services integrated in an economic evaluation. This class of techniques is mainly used for the comparison of similar products and processes, which present the same function, and its aim is to subsidize the decision-making process in several levels. This methodology considers firstly the environmental indicator based in the life cycle inventory associated to a simplified risks of accidents to human health analysis which are classified according to the severity of consequences and the probability of occurrence and secondly an economical indicator calculated from the life cycle costs of the product. As to the information about the biodiesel evaluation, two sources have been considered. Regarding the palm oil, primary data have been used. Such data have been obtained from Grupo Agropalma the largest national oil producer; regarding ethanol, secondary sources have been used, that is, available data from literature. The literature and the experts responsible for biodiesel technology of production have provided other data and information regarding more particularly the biodiesel production. As to the petrodiesel, the data have been obtained from the international database and afterwards adapted to the Brazilian scenario, by means of information, provided by Petrobras. The petrodiesel information was determined to 26 liters of fuel and the one concerning the biodiesel to 30 liters. Such quantities have been calculated considering the amount of the necessary product in order to generate 1,000 MJ of energy in internal combustion engines. Data have been collected to the stages of source extraction and transformation; distribution, use and final disposition have not been considered. The final result of the analysis shows biodiesel as the most ecoefficent option. The large difference between the two alternatives is the best environmental performance of the biodiesel which is justified chiefly due to the reduced consumption of material resources and the low toxicity of the product since the necessary raw material for its formation (the anhydrous ethanol and the palm oil) has renewable nature and during the production of the petrodiesel there is contact with many volatile hydrocarbons unlikely the biodiesel. This paper provides information, which may help the decision-making process of the Brazilian biodiesel use, besides that, it contributes with life cycle inventories, which may help in the development of a Brazilian LCA (Life cycle assessment) database.
4

Análise de ecoeficiência: avaliação do desempenho econômico-ambiental do biodiesel e petrodiesel. / Eco-efficiency analysis: environmental-economic assessment of biodiesel and petrodiesel.

Vianna, Fernanda Cristina 21 July 2006 (has links)
O biodiesel é a mais provável alternativa ao petrodiesel. É constituído de uma mistura de ésteres metílicos ou etílicos de ácidos graxos, obtidos da reação de transesterificação entre qualquer triglicerídio e um álcool de cadeia curta, metanol ou etanol. Possui praticamente as mesmas propriedades do petrodiesel, mas comparado a este, pode eliminar as emissões de óxido de enxofre e reduzir as emissões de CO2. O Brasil vem sendo apontado como futuro líder na produção de biodiesel, devido às suas excelentes condições de clima, solo, e imensa extensão territorial, que são propícias para a plantação de diversas oleaginosas. Com tantas especulações, o governo federal brasileiro criou o Programa Nacional de Produção e Uso de Biodiesel (PNPB), visando a implementação da produção e uso do biodiesel de forma sustentável. Para tanto, uma lei federal foi promulgada em 2005, estabelecendo a adição de 5% de biodiesel ao petrodiesel vendido ao consumidor final. Esta lei deve ser implementada em um período de 5 anos, nos quais as empresas produtoras devem começar usando um mínimo de 2% em um período de 3 anos. Este trabalho apresenta uma avaliação econômica-ambiental comparativa entre biodiesel (de óleo de palma e etanol) e petrodiesel para as condições brasileiras, usando a Análise de Ecoeficiência desenvolvida pela BASF. Esta análise pertence a uma classe de técnicas da gestão ambiental que visa avaliar o desempenho ambiental de produtos, processos e serviços, de forma integrada a uma avaliação econômica. Esta classe de técnicas é usada, principalmente, para a comparação de produtos similares e de processos que executem uma mesma função, visando à geração de subsídios para a tomada de decisão em diversos níveis. Esta metodologia considera um indicador ambiental baseado em um inventário de ciclo de vida associado a uma avaliação simplificada de riscos de acidentes à saúde humana, os quais são classificados de acordo com a severidade das conseqüências e probabilidade de ocorrência e; um indicador econômico, calculado a partir dos custos do ciclo de vida do produto. No que diz respeito à avaliação do biodiesel, para os dados relativos ao óleo de dendê (ou palma), utilizaram-se dados de campo, obtidos junto ao Grupo Agropalma, maior produtor nacional do óleo e, no que diz respeito ao etanol foram utilizadas fontes secundárias, ou seja, dados disponíveis em literatura. Outros dados e informações relacionados mais especificamente com a produção do biodiesel foram adquiridos de literatura e levantados junto a especialistas e responsáveis pela tecnologia de produção do mesmo. Com relação ao petrodiesel, os dados foram obtidos de base de dados internacionais e, posteriormente, adaptados à realidade brasileira, por meio de informações obtidas junto à Petrobras e à literatura especializada. As informações relacionadas ao petrodiesel foram levantadas para 26 litros de combustível e, as referentes ao biodiesel para 30 litros. Estas quantidades foram determinadas considerando-se o quanto de produto faz-se necessário para a geração de 1.000 MJ de energia em motores de combustão interna. Os dados foram coletados para as etapas de extração dos recursos e transformação dos mesmos, não sendo consideradas as etapas de distribuição, uso e disposição final.Como resultado, tem-se o biodiesel como opção mais ecoeficiente. O grande diferencial entre as duas alternativas é o desempenho ambiental do biodiesel, fato esse, justificado principalmente, pelo reduzido consumo de recursos materiais e a baixa toxicidade do produto, pois as matérias-primas necessárias para sua formação (o etanol e o óleo de dendê) têm caráter renovável e, durante a produção do petrodiesel existe o contato com muitos hidrocarbonetos voláteis, algo que não ocorre com o biodiesel. Este estudo fornece informações que podem auxiliar na tomada de decisões sobre a consolidação do uso do biodiesel no Brasil, além disso, contribui com inventários do ciclo de vida, que podem auxiliar no desenvolvimento de um banco de dados de ACV (Avaliação do ciclo de vida) representativos da realidade brasileira. / Biodiesel is the most likely alternative to petrodiesel. It is composed of methyl or ethyl esters from fatty acids, obtained by a transesterification reaction between any triglycerides and an alcohol with short chain, methanol or ethanol. It has almost the same properties of petrodiesel, but comparing with this, it can eliminate the sulfur oxides emissions and significantly reduce the CO2 emissions. Brazil is being considered as a future leader in biodiesel production due to its excellent climate and soil condition and vast territorial extension conducive to a crop of varied oil plants. Around so many speculations, Brazilian federal government has created the National Biodiesel Production and Use Program (PNPB) aiming to the implementation of a sustainable biodiesel production and use. Focusing this issue, a federal law was promulgated in 2005 in order to establish the addition of 5% biodiesel to the petrodiesel sold to the ultimate consumer. This fact should be implemented within a 5 – year period in which companies should start using the minimum of 2% biodiesel within a 3 – year period. This paper presents an environmental and economic comparison between biodiesel (from palm oil and ethanol) and petrodiesel regarding Brazilian conditions, according to the Eco-Efficiency Analysis developed by BASF. This analysis belongs to a class of techniques of the environmental management, which aims to evaluate the environmental performance of products, processes and services integrated in an economic evaluation. This class of techniques is mainly used for the comparison of similar products and processes, which present the same function, and its aim is to subsidize the decision-making process in several levels. This methodology considers firstly the environmental indicator based in the life cycle inventory associated to a simplified risks of accidents to human health analysis which are classified according to the severity of consequences and the probability of occurrence and secondly an economical indicator calculated from the life cycle costs of the product. As to the information about the biodiesel evaluation, two sources have been considered. Regarding the palm oil, primary data have been used. Such data have been obtained from Grupo Agropalma the largest national oil producer; regarding ethanol, secondary sources have been used, that is, available data from literature. The literature and the experts responsible for biodiesel technology of production have provided other data and information regarding more particularly the biodiesel production. As to the petrodiesel, the data have been obtained from the international database and afterwards adapted to the Brazilian scenario, by means of information, provided by Petrobras. The petrodiesel information was determined to 26 liters of fuel and the one concerning the biodiesel to 30 liters. Such quantities have been calculated considering the amount of the necessary product in order to generate 1,000 MJ of energy in internal combustion engines. Data have been collected to the stages of source extraction and transformation; distribution, use and final disposition have not been considered. The final result of the analysis shows biodiesel as the most ecoefficent option. The large difference between the two alternatives is the best environmental performance of the biodiesel which is justified chiefly due to the reduced consumption of material resources and the low toxicity of the product since the necessary raw material for its formation (the anhydrous ethanol and the palm oil) has renewable nature and during the production of the petrodiesel there is contact with many volatile hydrocarbons unlikely the biodiesel. This paper provides information, which may help the decision-making process of the Brazilian biodiesel use, besides that, it contributes with life cycle inventories, which may help in the development of a Brazilian LCA (Life cycle assessment) database.
5

Organic Chemical Characterization Of Primary And Secondary Biodiesel Exhaust Particulate Matter

Kasumba, John 01 January 2015 (has links)
Biodiesel use and production has significantly increased in the United States and in other parts of the world in the past decade. This change is driven by energy security and global climate legislation mandating reductions in the use of petroleum-based diesel. Recent air quality research has shown that emission of some pollutants such as CO, particulate matter (PM), SO2, hydrocarbons, and carcinogenic polycyclic aromatic hydrocarbons (PAHs) is greatly reduced with biodiesel. However, studies have also shown that some unregulated emissions, such as gas-phase carbonyls, are increased with biodiesel combustion. Very limited research has been done to investigate the particle-phase carbonyl and quinone emissions from biodiesel combustion. Also, very limited studies have investigated the ozone oxidation of biodiesel exhaust PM. Fatty acid methyl esters (FAMEs) are found in high abundance in biodiesel exhaust PM. The presence of these FAMEs in biodiesel exhaust PM can potentially alter the kinetics of the reactions between ozone and particle-phase PAHs. In this study, an Armfield CM-12 automotive light-duty diesel engine operated on a transient drive cycle was used to generate PM from various waste vegetable oil (WVO) and soybean biodiesel blends (containing 0%, (B00), 10% (B10), 20% (B20), 50% (B50), and 100% (B100) biodiesel by volume). The primary PM emissions were sampled using Teflon-coated fiberfilm filters. Laboratory PAHs, FAMEs, and B20 exhaust PM were exposed to ~0.4 ppm ozone for time periods ranging from 0-24 hours in order to study the effect of FAMEs and biodiesel exhaust PM on the ozonolysis of PAHs. Organic chemical analysis of samples was performed using gas chromatography/mass spectrometry (GC/MS). PAHs, carbonyls, FAMEs, and n-alkanes were quantified in the exhaust PM of petrodiesel, WVO and soybean fuel blends. The emission rates of the total PAHs in B10, B20, B50, and B100 exhaust PM decreased by 0.006-0.071 ng/µg (5-51%) compared to B00, while the emission rates for the FAMEs increased with increasing biodiesel content in the fuel. The emission rates of the total n-alkanes in B10, B20, B50, and B100 exhaust PM decreased by 0.5-21.3 ng/µg (4-86%) compared to B00 exhaust PM. The total emission rates of the aliphatic aldehydes in biodiesel exhaust PM (B10, B20, B50, and B100) increased by 0.019-2.485 ng/µg (36-4800%) compared to petrodiesel. The emission rates of the total aromatic aldehydes, total aromatic ketones, and total quinones all generally decreased with increasing biodiesel content in the fuel. With the exception of benzo[a]pyrene, the pseudo-first order ozone reaction rate constants of all the PAHs decreased by 1.2-8 times in the presence of the FAMEs. Phenanthrene, fluoranthene, and pyrene were the only PAHs detected in the B20 exhaust PM, and their ozone reaction rate constants were about 4 times lower than those obtained when the PAHs alone were exposed to ozone. The findings of this study indicate that there are both positive and negative effects to emissions associated with biodiesel use in light-duty diesel engines operating on transient drive cycle.
6

The Study of Variations in the Properties of Biodiesel on Addition of Antioxidants

Kandala, Hiranmayee 01 August 2009 (has links)
This research studies variations in biodiesel upon addition of different concentrations of antioxidant and petrodiesel additives. Oxidation onset temperature, oxidation induction time, oxidative stability, thermal stability, crystallization onset temperature and moisture retention properties of the biodiesel, with and without antioxidants have been studied. Antioxidants like BHT, BHA, PrG, Vit E and Vit C were added to the biodiesel during the study. These samples were analyzed using the PDSC, TGA, DSC and TGA-SA instrumentation. The results of this research show an improvement in the OOT, OIT and Oxidative stability of biodiesel with the addition of antioxidants and by blending the biodiesel with different amounts of Petro-diesel. A significant improvement in oxidative stability of biodiesel has been observed with the addition of antioxidants and petrodiesel. There was no significant change noticed in the thermal stability, crystallization and the moisture retention properties of biodiesel. I hope that this research would help improving the oxidative stability of the biodiesel. The results from the analysis made in this study would also be helpful in designing a better antioxidant and aid in improving the present experimental methods for the OIT and thermal analysis.

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