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Exergy efficiency analysis of chemical and biochemical stages involved in liquid biofuels production processes

Arredondo, Hector Ivan Velasquez; Oliveira Junior, Silvio de; Benjumea, P.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD Publicador: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.24%
Liquid biofuels can be produced from a variety of feedstocks and processes. Ethanol and biodiesel production processes based on conventional raw materials are already commercial, but subject to further improvement and optimization. Biofuels production processes using lignocellulosic feedstocks are still in the demonstration phase and require further R&D to increase efficiency. A primary tool to analyze the efficiency of biofuels production processes from an integrated point of view is offered by exergy analysis. To gain further insight into the performance of biofuels production processes, a simulation tool, which allows analyzing the effect of process variables on the exergy efficiency of stages in which chemical or biochemical reactions take place, were implemented. Feedstocks selected for analysis were parts or products of tropical plants such as the fruit and flower stalk of banana tree, palm oil, and glucose syrups. Results of process simulation, taking into account actual process conditions, showed that the exergy efficiencies of the acid hydrolysis of banana fruit and banana pulp were in the same order (between 50% and 60%), lower than the figure for palm oil transesterification (90%), and higher that the exergy efficiency of the enzymatic hydrolysis of flower stalk (20.3%). (C) 2011 Elsevier Ltd. All rights reserved.

Biocombustíveis - Aspectos sociais e econômicos: comparação entre Brasil, Estados Unidos e Alemanha; Biofuels Comparison between Brazil, United States and Germany regarding social and economic aspects.

Gorren, Regiane Catarina Ribeiro
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 16/09/2009 PT
Relevância na Pesquisa
37.47%
Esta dissertação apresenta uma análise comparativa dos aspectos sociais e econômicos decorrentes da produção dos biocombustíveis, etanol e biodiesel, nos principais países produtores e consumidores da atualidade Brasil, Estados Unidos e Alemanha. Para tal, os biocombustíveis foram analisados por intermédio dos dados das matrizes energéticas, da produção de matéria-prima e do biocombustível, do consumo interno, das políticas de suporte, barreiras tarifárias e não tarifárias, bem como dos gargalos existentes. Nos aspectos econômicos foram abordados indicadores da macroeconomia, indicadores específicos para biocombustíveis, a logística e a presença de subsídios. Nos aspectos sociais, a situação do trabalhador rural foi analisada enfatizando o trabalhador temporário imigrante na agricultura. O histórico das políticas possibilitou verificar a associação entre os estímulos políticos e a variação na produção. A construção dos cenários permitiu estimar a área necessária para expansão da produção de biocombustíveis. Neste grupo heterogêneo de países, em que as características sociais e econômicas são distintas, verificou-se que a legislação apresenta peculiaridades conforme a realidade de cada país. Com relação aos aspectos sociais...

Território, poder e biocombustíveis: as ações do Estado brasileiro no processo de regulação terriotorial para a produção de recursos energéticos alternativos; Territory, power and biofuels: actions of the Brazilian State in the regulation process for the production of alternative energy sources

Freitas, Elisa Pinheiro de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 21/03/2013 PT
Relevância na Pesquisa
37.29%
O Brasil se destaca, dentre o conjunto de países, como aquele que engendrou e consolidou o uso de recursos energéticos alternativos aos combustíveis fósseis, como por exemplo, os biocombustíveis. A condição de player mundial de etanol, biocombustível produzido a partir da cana-de-açúcar, foi alcançada pelo país em decorrência dos significativos aportes financeiros concedidos pelo Estado ao setor sucroalcooleiro desde o final do século XIX e, sobretudo, durante a década de 1970, por meio do Programa Nacional do Álcool (PNA) cujo objetivo era diminuir a dependência do país em relação ao petróleo importado. Num período que se caracteriza, dentre outras questões, por uma corrida global por alimentos e novas fontes de energia limpa para suprir a crescente demanda mundial, o Brasil desponta no cenário internacional como o país que possui uma situação sui generis, uma vez que com o seu vasto território, poderia, supostamente, conciliar a produção de alimentos e de matérias-primas para a geração dos biocombustíveis (etanol e biodiesel). Investigou-se, portanto, a ocorrência simultânea dos seguintes fenômenos: a intensificação de compra de terras brasileiras por estrangeiros (para a produção de commodities agrícolas...

Biocombustíveis, alimentos e petróleo: uma análise retrospectiva da experiência brasileira; Biofuels, Food and Oil: A Retrospective Analysis of Brazilian Experience.

Rico, Julieta Andrea Puerto
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 18/07/2013 PT
Relevância na Pesquisa
37.17%
Os biocombustíveis são produzidos de acordo a conjunturas do mercado de petróleo e das commodities agrícolas, e são inseridos na esfera produtiva dos derivados de petróleo através de incentivos governamentais. O objetivo do trabalho foi analisar a relação entre os setores de biocombustíveis, alimentos e petróleo recorrendo ao referencial teórico sobre renda dos recursos naturais e ao método histórico. Na primeira etapa foram identificados vasos comunicantes entre os preços do petróleo e de algumas commodities agrícolas, observando que o excedente criado com o petróleo influencia os preços das commodities agrícolas e, a partir do processo de financeirização desta esfera, os comercializadores oligopsônicos de alimentos podem extrair um excedente dos proprietários da terra. Na segunda etapa foram analisados os programas brasileiros. Foi observado que no caso do biodiesel a criação de rendas diferenciais a partir da produção de matérias primas da agricultura familiar fica restringida. A obtenção deste tipo de rendas depende do preço de mercado dos óleos vegetais provenientes da agricultura capitalista e de acordo aos incentivos formulados para o PNPB ainda não se configura um mercado de referência que permita escolher o mercado de energia sendo preferível auferir a renda da terra no mercado de óleos vegetais para alimentação. Análise comparativa revelou com significância estatística que os preços dos óleos vegetais tendem a ser superiores aos dos fósseis equivalentes. Os resultados da pesquisa permitem concluir que as tentativas de viabilizar o biodiesel: a) na década de 1970 careceram de articulações políticas para superar as dificuldades impostas pelas condições de mercado...

Requisitos de sustentabilidade para biocombustíveis e as normas do direito internacional; Sustainability requirements for biofuels and the rules of the international law

Bruna de Barros Correia
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 18/02/2011 PT
Relevância na Pesquisa
37.24%
Frente às mudanças climáticas, a produção e o consumo de biocombustíveis têm despertado muito interesse em todo o mundo. Esse contexto fez com que surgissem compromissos para a produção e o uso dos biocombustíveis com a sustentabilidade. Princípios, critérios e indicadores de sustentabilidade são propostos e já são utilizados para monitorar a produção e o consumo de biocombustíveis através de iniciativas de sustentabilidade, cujo objetivo é evitar que atividades prejudiciais ao meio ambiente e à sociedade sejam incorporadas ao processo produtivo. Apesar de muitos esforços, não há uma padronização quanto aos requisitos de sustentabilidade que devem ser considerados em tais iniciativas. Isso faz com que haja uma multiplicidade de critérios, os quais nem sempre visam o desenvolvimento sustentável e, conseqüentemente, podem contribuir para a criação de barreiras comerciais. Para evitar que sejam criadas medidas protecionistas, a Organização Mundial do Comércio (OMC) proíbe a manutenção das barreiras não tarifárias quando não existirem mais as circunstâncias e objetivos que motivaram a sua criação, ou quando tais circunstâncias e objetivos possam ser atendidos de uma maneira menos restritiva ao comércio. Frente aos conflitos legais entre meio ambiente...

Biodiversidade e os esquemas de certificação de biocombustíveis; Biodiversity and the certification schemes for biofuels

Camila Ortolan Fernandes de Oliveira
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 30/08/2013 PT
Relevância na Pesquisa
37.29%
A sustentabilidade dos biocombustíveis é uma questão polêmica, que ganhou grande dimensão desde a segunda metade da década passada. Nesse contexto, biodiversidade é um dos aspectos mais mencionados no debate internacional. Em função das pressões de diferentes segmentos sociais, critérios de sustentabilidade foram definidos e têm condicionado a aplicação de políticas de fomento aos biocombustíveis. Na prática, esquemas de certificação têm sido usados de forma crescente e nada indica que essa tendência seja alterada. Assim, a futura produção de etanol de cana de açúcar no Brasil, e a competitividade da produção nacional em mercados internacionais, estarão condicionadas a que sustentabilidade seja uma realidade, e possa ser comprovada. No Brasil, muito pouco se sabe sobre os impactos da produção de cana, e de etanol, sobre a biodiversidade, e foi isso que motivou esta dissertação. Seu objetivo geral é o entendimento da questão biocombustíveis-biodiversidade, incluindo a identificação do conhecimento existente, das diferentes visões, das aspirações, etc. A análise foi feita com foco na produção de etanol de cana, nas condições brasileiras, e de suas perspectivas. Um dos objetivos específicos foi definido na avaliação dos esquemas de certificação...

Potenciais impactos no comércio internacional de biocombustíveis associados à implementação de esquemas de certificação; Potential impacts on international biofuels trade associated with the implementation of certification schemes

Rachel Marini Ravagnani
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 15/08/2014 PT
Relevância na Pesquisa
37.37%
Em virtude do crescente reconhecimento dos impactos adversos que podem ser causados pelo uso intensivo dos derivados de petróleo, os biocombustíveis surgem com o fim de promover soluções para problemas relacionados à redução de emissões de gases de efeito estufa, segurança de suprimento energético e redução da dependência do petróleo e seus derivados. No entanto, em virtude do aumento do consumo dos biocombustíveis, a sustentabilidade na produção da matéria-prima e conversão do produto final passou a ser pressuposto para que o atendimento às questões mencionadas acima fossem, de fato, cumpridas. A preocupação quanto ao estabelecimento de barreiras comerciais em virtude da implementação de esquemas de certificação para atestar o cumprimento aos requisitos de sustentabilidade tem início neste ponto, para os biocombustíveis. Como o mercado internacional de combustíveis renováveis ainda é recente, a avaliação dos impactos econômicos originados por esquemas de certificação torna-se impraticável e, por esta razão foi proposta uma análise comparada à setores mais maduros e experientes em relação aos esquemas de certificação. A fim de realizar tal comparação artigos que descreviam impactos econômicos dos setores de alimentos e produtos florestais madeireiros foram analisados. Do exame realizado...

Intensified bioprocess for the anaerobic conversion of syngas to biofuels

Pereira, Filipa Maria Rodrigues; Reis, N.; Alves, M. M.; Sousa, D. Z.
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em 11/10/2010 ENG
Relevância na Pesquisa
37.24%
Syngas, composed mainly of CO, H2 and CO2 can be produced from several sources, including coal, oil and natural gas, tar sands, recalcitrant wastes and biomass. Syngas can be a potential feedstock for the sustainable production of biofuels and bulk chemicals. The selective biological conversion of syngas is a possible alternative to the chemical route. Nevertheless the biological route remains rather unexplored within the bioprocess engineering community. Some anaerobic microorganisms have the ability to use CO, H2 and CO2 and produce renewable biofuels such as ethanol, butanol, and methane. As in the stage of work planning, this work introduces the main issues in the topic of syngas fermentation to biofuels. The experimental work to be performed aims to develop a new anaerobic bioprocess for the conversion of syngas to biofuels, with principal interest in ethanol, butanol, and CH4. An oscillatory flow reactor, presenting efficient gas-liquid mass transfer rates, will be explored carrying out proof-ofconcept experiments using pure and defined mixed anaerobic cultures. In a later stage, an energy based metabolic model will be developed to predict products formation according to specific environmental conditions.

The role of biochemical engineering in the production of biofuels from microalgae

Costa, Jorge Alberto Vieira; Morais, Michele Greque de
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.37%
Environmental changes that have occurred due to the use of fossil fuels have driven the search for alternative sources that have a lower environmental impact. First-generation biofuels were derived from crops such as sugar cane, corn and soybean, which contribute to water scarcity and deforestation. Second-generation biofuels originated from lignocellulose agriculture and forest residues, however these needed large areas of land that could be used for food production. Based on technology projections, the third generation of biofuels will be derived from microalgae. Microalgae are considered to be an alternative energy source without the drawbacks of the first- and second-generation biofuels. Depending upon the growing conditions, microalgae can produce biocompounds that are easily converted into biofuels. The biofuels from microalgae are an alternative that can keep the development of human activity in harmony with the environment. This study aimed to present the main biofuels that can be derived from microalgae.

Produção e Caracterização de Biocombustíveis por Craqueamento de Óleo Vegetais via Catálise com Bauxita; Production and characterization of the biofuels by cracking of vegetable oils through bauxite catalysis

PRADO, Cinara Machado Rodrigues do
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Química; Educação em Química Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Química; Educação em Química
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
37.34%
In this work, raw bauxite, thermally activated calcined bauxite, calcined bauxite underwent acid treatment were the catalysts tested by its potential in the thermal catalytic cracking reaction looking forward to the production of biofuels from commercial soybean oil as an alternative to fossil fuels. The materials were characterized by the techniques ICP-OES, infrared spectroscopy, thermal analysis, X-ray diffraction and textural analysis. The chromatographic analysis of the biofuels obtained by cracking of commercial soybean oil showed hydrocarbon compounds such as alkanes, alkenes and aromatics, as well as some oxygenated compounds such as carboxylic acids, ketones and alcohols. The products generated by the thermal catalytic cracking process with thermally activated calcined bauxite showed better results than the thermal cracking products because of the low quantity of acids present, which provided biofuels with a lower acidity index, and absence of acrolein. Therefore, the catalyst which was used demonstrated activity in the secondary cracking process, in which fatty acids decompose and give rise to hydrocarbons. The cracking tests with raw bauxite generated a lower biofuels yield and significant amount of solid product and residual oil making unfeasible the process. In order to evaluated the potential of used industrial waste sources for production of alternative fuels...

World Oil Price and Biofuels : A General Equilibrium Analysis

Timilsina, Govinda R.; Mevel, Simon; Shrestha, Ashish
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
37.34%
The price of oil could play a significant role in influencing the expansion of biofuels. However, this issue has not been fully investigated yet in the literature. Using a global computable general equilibrium model, this study analyzes the impact of oil price on biofuel expansion, and subsequently, on food supply. The study shows that a 65 percent increase in oil price in 2020 from the 2009 level would increase the global biofuel penetration to 5.4 percent in 2020 from 2.4 percent in 2009. A doubling of oil price in 2020 from its baseline level, or a 230 percent increase from the 2009 level, would increase the global biofuel penetration in 2020 to 12.6 percent. The penetration of biofuels is highly sensitive to the substitution possibility between biofuels and their fossil fuel counterparts. The study also shows that aggregate agricultural output drops due to an oil price increase, but the drop is small in major biofuel producing countries as the expansion of biofuels would partially offset the negative impacts of the oil price increase on agricultural outputs. An increase in oil price would reduce global food supply through direct impacts as well as through diversion of food commodities and cropland toward the production of biofuels.

Biofuels : Markets, Targets and Impacts

Timilsina, Govinda R.; Shrestha, Ashish
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
37.44%
This paper reviews recent developments in biofuel markets and their economic, social and environmental impacts. Several countries have introduced mandates and targets for biofuel expansion. Production, international trade and investment have increased sharply in the past few years. However, several existing studies have blamed biofuels as one of the key factors behind the 2007-2008 global food crisis, although the magnitudes of impacts in these studies vary widely depending on the underlying assumptions and structure of the models. Existing studies also have huge disparities in the magnitude of long-term impacts of biofuels on food prices and supply; studies that model only the agricultural sector show higher impacts, whereas studies that model the entire economy show relatively lower impacts. In terms of climate change mitigation impacts, there exists a consensus that current biofuels lead to greenhouse gas mitigation only when greenhouse gas emissions related to land-use change are not counted. If conversion of carbon rich forest land to crop land is not avoided...

Second-Generation Biofuels : Economics and Policies

Carriquiry, Miguel A.; Du, Xiaodong; Timilsina, Govinda R.
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
37.44%
Recent increases in production of crop-based (or first-generation) biofuels have engendered increasing concerns over potential conflicts with food supplies and land protection, as well as disputes over greenhouse gas reductions. This has heightened a sense of urgency around the development of biofuels produced from non-food biomass (second-generation biofuels). This study reviews the economic potential and environmental implications of production of second-generation biofuels from a variety of various feedstocks. Although second-generation biofuels could significantly contribute to the future energy supply mix, cost is a major barrier to increasing commercial production in the near to medium term. Depending on various factors, the cost of second-generation (cellulosic) ethanol can be two to three times as high as the current price of gasoline on an energy equivalent basis. The cost of biodiesel produced from microalgae, a prospective feedstock, is many times higher than the current price of diesel. Policy instruments for increasing biofuels use...

Second Generation Biofuels: Economics and Policies

Carriquiry, Miguel A.; Du, Xiaodong; Timilsina, Govinda R.
Fonte: Banco Mundial Publicador: Banco Mundial
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
37.4%
This study reviews economics of production of second generation biofuels from various feedstocks, including crop and wood/forestry residues, lignocellulosic energy crops, jatropha, and algae. The study indicates that while second generation biofuels could significantly contribute to the future energy supply mix, cost is a major barrier to its commercial production in the near to medium term. Depending upon type of biofuels, feedstock prices and conversion costs, the cost of cellulosic ethanol is found to be two to three times higher than the current price of gasoline on an energy equivalent basis. The median cost (across the studies reviewed) of biodiesel produced from microalgae, a prospective feedstock, is seven times higher than the current price of diesel, although much higher cost estimates have been reported. As compared with the case of first generation biofuels, in which feedstock can account for over two-thirds of the total costs, the share of feedstock in the total costs is relatively lower (30-50%) in the case of second generation biofuels. While significant cost reductions are needed for both types of second generation biofuels, the critical barriers are at different steps of the production process. For cellulosic ethanol...

Development of Biofuels in China : Technologies, Economics and Policies

Shiyan, Chang; Lili, Zhao; Timilsina, Govinda R.; Xiliang, Zhang
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
37.4%
China promulgated the Medium and Long-Term Development Plan for Renewable Energy in 2007, which included targets of 2010 and 2020 for various renewable energy technologies including biofuels. The 2010 biofuel targets were met and even surpassed except for non-grain fuel ethanol; however, there is debate on whether and how the country will be able to meet the 2020 biofuels target. This paper provides a resource and technological assessment of biofuel feedstocks, compares biofuel production costs from various feddstocks and technologies, and evaluates policies introduced in the country for the development of biofuels. The paper also presents the projections on the production of biofuels under various policy scenarios. The study shows that China can potentially satisfy its non-grain fuel ethanol target by 2020 from the technology perspective. But it will probably fall far short of this target without additional fiscal incentives as production costs of non-grain feedstock based biofuels are expected to remain relatively high. By contrast...

Are Biofuels Economically Competitive with Their Petroleum Counterparts? Production Cost Analysis for Zambia

Sinkala, Thomson; Timilsina, Govinda R.; Ekanayake, Indira J.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
37.37%
With increased global interest in biofuels, Zambia, a Sub- Saharan African country that entirely depends on imports for its petroleum supply, is planning to implement blending mandates for biofuels. But, a large number of issues—including production costs of biofuels, land requirements to meet the mandates, and environmental benefits—have not yet been explored. This study aims to contribute in filling this gap. It finds that depending on feedstock type, costs of ethanol production range from US$0.360 a liter to US$0.680 a liter while the costs for biodiesel production range from US$0.612 a liter to US$0.952 a liter. Even if lower energy contents of biofuels are taken into account, the analysis shows that biofuels are cheaper than their petroleum counterparts. Considering the cost advantage of these biofuels over petroleum products and the availability of surplus agricultural land, Zambia is likely to benefit from the development of a biofuel industry. Biofuels is expected to reduce Zambia’s petroleum import bill, which currently stands at more than US$700 million, enhance food security by providing incentives to increase yields, and increase affordability and accessibility to modern energy in the country where 77 percent of the population still lacks access to modern energy. It could also stimulate rural employment and development.

Biofuels: food for thought or fueling world food prices? Exploring the connection between rising food price and alternative fuels

Sykes, David
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Relatório
Relevância na Pesquisa
37.57%
The steep increase in the price of oil since 2002, the growing debate over peak oil production, and unequivocal evidence that the climate is warming as a result of increased greenhouse gas emissions have led countries around the world to seek alternatives to oiL Biofuels are increasingly viewed as one alternative to oil that holds a great deal of promise. Proponents of biofuels claim that they have the potential to be clean burning, renewable sources of energy that will aid countries around the world in lessening their dependence on oil, particularly imported oil. This report seeks firstly to address the most significant problem commonly associated with the increased use of biofuels. The 'food versus fuel' debate has arisen as a major challenge to increased biofuels production. There is now clear and unequivocal evidence that biofuel production has contributed to the skyrocketing price of food around the world. It is also clear that biofuels are simply one of a number of challenges that face tl1e world in ensuring its poorest people have food security. The rising price of energy, the growth of the developing world, particularly China, and the spectre of climate change all pose long-term challenges to agricultural production. Given these monumental challenges already facing countries around the world...

Biofuels in Africa : Opportunities, Prospects, and Challenges

Mitchell, Donald
Fonte: World Bank Publicador: World Bank
Tipo: Publications & Research :: Publication; Publications & Research :: Publication
ENGLISH
Relevância na Pesquisa
37.34%
Biofuels offer new opportunities for African countries. They can contribute to economic growth, employment, and rural incomes. They can become an important export for some countries and provide low-cost fuel for others. There is also a potentially large demand for biofuels to meet the rapidly growing need for local fuel. Abundant natural resources and low-cost labor make producing biofuel feedstock's a viable alternative to traditional crops; and the preferential access available to most African countries to protected markets in industrial countries provides unique export opportunities. Biofuels also bring challenges and risks, including potential land-use conflicts, environmental risks, and heightened concerns about food security. This book examines the potential of African countries to produce biofuels for export or domestic consumption and looks at the policy framework needed. It is part of the effort by the World Bank's Africa region to examine critical issues that affect the region and to recommend policies that effectively address these issues while providing an enabling environment for the private sector. The book is intended to inform policy makers and the larger development community of the global and domestic market opportunities facing biofuel producers...

Considering Trade Policies for Liquid Biofuels

Kojima, Masami; Mitchell, Donald; Ward, William
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: ESMAP Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
37.44%
This report addresses the issues associated with trade in liquid biofuels is a second Energy Sector Management Assistance Program report on biofuels, and part of a broader assessment of bioenergy undertaken by the World Bank. The report asks how liberalizing trade in liquid biofuels might affect biofuel production and consumption. Bioenergy is playing an increasingly important role as an alternative and renewable source of energy. Bioenergy includes solid biomass, biogas, and liquid biofuels. Combustion of biomass residues for heat and power generation is commercially viable without government support in some applications. Liquid biofuels made from biomass are attracting growing interest worldwide, driven by concerns about energy security, climate change, and local environmental considerations and a desire to support domestic agriculture. The global liquid biofuel market today utilizes so called first generation technologies and relies mainly on agricultural food or feed crops for feedstock. Second generation biofuels...

Thermus Thermophilus as a Thermophilic Model Organism for Biofuels Production

Liu, Jing
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
37.24%
Maciek R. Antoniewicz; The potential of using Thermus thermophilus HB8, a thermophilic bacterium, for the production of biofuels was investigated in this work. T. thermophilus is a thermophilic bacterium that thrives naturally at high temperatures, typically around 70-85??C. This bacterium has significant potential in the field of biotechnology because of its unique physical and biochemical properties, especially for the production of low-boiling biofuels. In this project, the growth of Thermus thermophilus HB8 was characterized in batch cultures under defined experimental growth conditions. First, we optimized a defined growth medium to maximize the growth rate of T. thermophilus without the need to use yeast extract in the medium. After that, growth rates were measured under aerobic growth conditions for temperatures ranging between 50??C and 90??C with glucose as the only carbon source. The optimum growth temperature was 80??C and the maximum growth rate of T. thermophilus was 0.28 1/hr, which corresponds to a doubling time of about 2.5 hours. In the growth experiments, T. thermophilus was cultured in custom constructed mini-bioreactors (at 10-mL scale) that were constructed using Hungate tubes and septum caps. For the growth experiments...