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Identificação dos gargalos e estabelecimento de um plano de ação para o sucesso do Programa Brasileiro do Biodiesel. / Identification of shortfalls and establishment of a workplan for the success of the Brazilian Biodiesel Program.Maurício Cintra do Prado de Salles Penteado 28 September 2005 (has links)
A crescente pressão mundial pelo desenvolvimento de tecnologias automotivas menos poluentes de emissões de combustíveis, incluindo o de combustiveis alternativos, foi a forma de impulsionar a tecnologia do Biodiesel, de origem não fóssil, derivados de fontes renováveis, visando substituir, gradualmente, o uso do óleo diesel, na matriz energética mundial. A diretiva americana Clean air Act amendment of 1990, a Lei S-517 e a diretiva européia 2003/30/EC of the European Parliament and of the Council of 8 May 2003 instituíram a adição do Biodiesel no óleo diesel. Nos Estados Unidos, este teor é de 20%, e, na Europa, é obrigatória a adição de 2%, em 2005, e será de 5,75%, em 2010. Dentro deste contexto, o Biodiesel necessita ser implementado no Brasil, de maneira gradual. A Lei brasileira 11097/05 tornará obrigatória sua adição de 2% (Biodiesel B2), em 2008 (ou de cerca de 840 milhões de litros de Biodiesel, do montante estimado de demanda do óleo diesel, de 42 bilhões de litros, em 2008), e de 5% (Biodiesel B5), em 2013. O objetivo deste trabalho é o de se identificarem alguns gargalos existentes, no âmbito técnico-econômico, no Programa Brasileiro do Biodiesel, e o de se estabelecer um plano de ação para o sucesso da implementação deste programa. No plano de ação, estão traçados possíveis cenários, com dois focos distintos: o de receita líquida máxima ao governo, sendo esta uma visão parcial de custeio (através dos cenários de substituição de importações do óleo diesel pelo Biodiesel e da introdução de óleo diesel / Biodiesel em veículos leves), e o do número máximo de empregos gerados, em 2008 e em 2013. A metodologia de pesquisa se baseia em pesquisa bibliográfica e na análise de dados coletados, que apontam para a urgente necessidade de isenção de impostos e de subsídios governamentais, para se viabilizar a produção das oleaginosas da mamona e da soja, a preços competitivos em relação ao óleo diesel. Dentro deste contexto, a mamona só se torna viável no âmbito social e técnico-social, de geração máxima de empregos, ao passo que as demais podem ser inseridas no contexto econômico e técnico-econômico, de receita líquida máxima ao governo. / The increasing demand for the development of automotive technologies of less polluting fuel emissions, including that of alternative fuels, has been the way to foster Biodiesel technology, of non-fossil origin, derived from renewable sources, aiming at gradually substituting the use of diesel oil, in the worldwide energetic matrix. The american directive Clean air Act amendment of 1990 , the Law S-517, and the European directive 2003/30/EC of the European Parliament of the Council of 8 May 2003 established the addition of Biodiesel in diesel oil. In the United States, this percentage is of 20%, and, in Europe, it is compulsory the addition of 2%, in 2005, and will be of 5,75%, in 2010. From that prospective, the Biodiesel needs to be gradually implemented in Brazil. The brazilian Law 11097/05 will demand the addition of 2% (Biodiesel B2), in 2008 (or about 840 millions of Biodiesel liters, of the estimated amount of diesel oil demand, of 42 billions of liters, in 2008), and of 5% (Biodiesel B5), in 2013. The objective of this project is to identify some existing shortfalls, on an technical-economic assessment, in the Brazilian Biodiesel Program, and to establish a workplan in order to achieve the success of this program. In this workplan, possible scenarios are identified, with two different focus: maximum government net revenue, on a partial cost prospective (via the scenarios of diesel oil importation replacement by Biodiesel and of diesel oil / Biodiesel intruction into light vehicles) and maximum jobs generation, in 2008 and in 2013. The research methodology is based on bibliographic survey and on data analysis, which shows the urgent need to viabilize castor and soybean oilseeds on competitive prices compared to that of diesel oil. From that prospective, castor is only viable on a social and technical-social aspect, of maximum employment generation, whereas the remaining oilseeds can be inserted into the economic and technical-economic context, of maximum governmental net income.
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Simulações de chamas turbulentas de etanol com modelo de turbulência k-E. / Turbulent ethanol spray flame simulations with k-E turbulence model.Fernando Luiz Sacomano Filho 21 June 2011 (has links)
Diversos equipamentos industriais utilizam processos de combustão com sprays. As principais vantagens deste processo estão relacionadas ao aumento do controle da chama e à maior segurança na logística do combustível líquido. Atualmente, o interesse na utilização de bio-combustíveis como alternativa para a redução na emissão de dióxido de carbono é crescente. Entre os tipos de bio-combustíveis o etanol se destaca por ser utilizado em vários países misturado à gasolina no setor de transportes. Partindo deste panorama, o presente trabalho apresenta a modelagem e simulação de uma chama turbulenta de spray de etanol. Os resultados das simulações realizadas são comparados com dados experimentais da literatura. O modelo resultante baseia-se no método dos volumes finitos para escoamentos com baixo número de Mach e em regime permanente. O spray foi calculado com a aproximação de escoamentos separados com uma formulação Euler-Lagrange, em que a fase dispersante é modelada com a abordagem Euleriana, enquanto que a fase dispersa é modelada com a abordagem Lagrangeana. As duas fases foram completamente acopladas nos dois sentidos. O modelo de turbulência k- Padrão foi utilizado na fase dispersante. A evaporação de gotículas foi considerada, em que o modelo de condutividade infinita foi utilizado para a fase líquida. Dessa forma, a distribuição de temperaturas no interior da gotícula é uniforme, porém varia conforme ela se move no spray. Para reproduzir os efeitos do resfriamento evaporativo, a combustão foi modelada com um modelo de folha de chama modificado que considerou uma função joint -PDF de fração de mistura e entalpia. Transferências de calor por radiação foram negligenciadas neste trabalho. Aproximações razoáveis foram obtidas entre os perfis medidos e calculados de temperatura média da fase gasosa e de distribuições de tamanhos de gotículas. Algumas discrepâncias foram observadas nas comparações entre os perfis do componente axial de velocidade média da fase gasosa, que foram atribuídas à difusão superestimada das quantidades médias transportadas pela fase gasosa nas simulações. / Several industrial equipments use combustion processes with sprays. The main advantages of this process are related to the increase in the flame control and in the safety of liquid fuel logistics. Currently, the interest on the utilization of biofuels as an alternative to the reduction of carbon dioxide emissions is increasing. Among the types of biofuels the ethanol stands out by being used blended with gasoline in the transport sector of several countries. From this overview, this work presents the modeling and simulation of an ethanol turbulent spray flame. The results of the simulations were compared with experimental data from the literature. The resulting model was based on the finite volume method for low Mach number and steady state flows. The spray was calculated using the Separated Flow method (SF) with an Euler-Lagrange model, where the gaseous phase was described by an Eulerian model and the liquid phase by a Lagrangian particle method. Both phases were fully coupled in order to account for shared effects. The turbulence model k- Standard was used to determine the dispersant phase. Evaporation of droplets was calculated with the assumption of the infinite-liquid-conductivity model, where the droplet inner temperature is uniform, but varies with the mass and heat transfer within the dispersant phase. To reproduce the effects of the evaporative cooling the combustion was modeled with a modified flamesheet model which regarded a jointed mixture fraction-enthalpy -PDF. Radiactive heat transfer was not accounted for in this work. Reasonable agreement between measured and computed mean profiles of temperature of the gas phase and droplet size distributions was achieved. Some deviations were observed in the mean velocity profiles comparisons between experimental data and simulations, which were assigned to the over predicted diffusion of the mean quantities transported by the gas phase.
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Ekonomická analýza změny vozového parku z klasických na alternativní pohony / ECONOMIC ANALYSIS OF CHANGE OF VEHICLE FLEET FROM CLASSIC TO ALTERNATIVE FUELSRůžičková, Tereza January 2017 (has links)
This diploma thesis deals with clean mobility, which becomes one of the current topics of today's society. Limited oil reserves and the state of the environment leads the goverments of developer countries to introduce alternative fuels in transport. The aim of the thesis is to clarify the economic costs and benefits of the practical application of clean mobility and to answer the question if the using of alternative fuels is economically rational. The Response is influenced by many factors and depends on the type of alternative fuel, the legislative framework of the country, the society awareness and others. Strength of the CNG's alternative fuel is mainly the lower fuel cost as well as for electromobility. The weakness of these fuels is the insufficient accessibility network of filling / charging places. An economic analysis of vehicle fleet modification of the Czech Environmental Inspectorate demonstrates that, under the current conditions, it is less costly to operate a vehicle with CNG alternative fuel. It is valid as well when the social cost of emissions are included.
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Carbon Nanotube/Microwave Interactions and Applications to Hydrogen Fuel Cells.Imholt, Timothy James 05 1900 (has links)
One of the leading problems that will be carried into the 21st century is that of alternative fuels to get our planet away from the consumption of fossil fuels. There has been a growing interest in the use of nanotechnology to somehow aid in this progression. There are several unanswered questions in how to do this. It is known that carbon nanotubes will store hydrogen but it is unclear how to increase that storage capacity and how to remove this hydrogen fuel once stored. This document offers some answers to these questions. It is possible to implant more hydrogen in a nanotube sample using a technique of ion implantation at energy levels ~50keV and below. This, accompanied with the rapid removal of that stored hydrogen through the application of a microwave field, proves to be one promising avenue to solve these two unanswered questions.
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The conceptual design of novel future UAV's incorporating advanced technology research componentsClarke, Adrian James January 2011 (has links)
There is at present some uncertainty as to what the roles and requirements of the next generation of UAVs might be and the configurations that might be adopted. The incorporation of technological features on these designs is also a significant driving force in their configuration, efficiency, performance abilities and operational requirements. The objective of this project is thus to provide some insight into what the next generation of technologies might be and what their impact would be on the rest of the aircraft. This work involved the conceptual designs of two new relevant full-scale UAVs which were used to integrate a select number of these advanced technologies. The project was a CASE award which was linked to the Flaviir research programme for advanced UAV technologies. Thus, the technologies investigated during this study were selected with respect to the objectives of the Flaviir project. These were either relative to those already being developed as course of the Flaviir project or others from elsewhere. As course of this project, two technologies have been identified and evaluated which fit this criterion and show potential for use on future aircraft. Thus we have been able to make a contirubtion knowledge in two gaps in current aerospace technology. The first of these studies was to investigate the feasibility of using a low cost mechanical thrust vectoring system as used on the X-31, to replace conventional control surfaces. This is an alternative to the fluidic thrust vectoring devices being proposed by the Flaviir project for this task. The second study is to investigate the use of fuel reformer based fuel cell system to supply power to an all-electric power train which will be a means of primary propulsion. A number of different fuels were investigated for such a system with methanol showing the greatest promise and has been shown to have a number of distinct advantages over the traditional fuel for fuel cells (hydrogen). Each of these technologies was integrated onto the baseline conceptual design which was identified as that most suitable to each technology. A UCAV configuration was selected for the thrust vectoring system while a MALE configuration was selected for the fuel cell propulsion system. Each aircraft was a new design which was developed specifically for the needs of this project. Analysis of these baseline configurations with and without the technologies allowed an assessment to be made of the viability of these technologies. The benefits of the thrust vectoring system were evaluated at take-off, cruise and landing. It showed no benefit at take-off and landing which was due to its location on the very aft of the airframe. At cruise, its performance and efficiency was shown to be comparable to that of a conventional configuration utilizing elevons and expected to be comparable to the fluidic devices developed by the Flaviir project. This system does however offer a number of benefits over many other nozzle configurations of improved stealth due to significant exhaust nozzle shielding.The fuel reformer based fuel cell system was evaluated in both all-electric and hybrid configurations. In the ell-electric configuration, the conventional turboprop engine was completely replaced with an all-electric powertrain. This system was shown to have an inferior fuel consumption compared to a turboprop engine and thus the hybrid system was conceived. In this system, the fuel cell is only used at loiter with the turboprop engine being retained for all other flight phases. For the same quantity of fuel, a reduction in loiter time of 24% was experienced (compared to the baseline turboprop) but such a system does have benefits of reduced emissions and IR signature. With further refinement, it is possible that the performance and efficiency of such a system could be further improved. In this project, two potential technologies were identified and thoroughly analysed. We are therefore able to say that the project objectives have been met and the project has proven worthwhile to the advancement of aerospace technology. Although these systems did not provide the desired results at this stage, they have shown the potential for improvement with further development.
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Methyl, ethyl and butyl soybean oil esters : alternative fuels for compression ignition enginesWagner, Larry E. January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
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Gracias a La Nacionalización De Los Hidrocarburos: a Critical Analysis of Bolivia’s Transition to Compressed Natural GasMcCollum, Jerl Levi 05 1900 (has links)
This paper critically analyzes the implementation of compressed natural gas and the ways in which it creates discourse in urban Bolivia. The rapidly developing nation is keen on making ubiquitous use of compressed natural gas a reality by issuing subsidies, citing increased mobility, savings, and environmental stewardship as the primary motives. Currently, eight out of every 10 public vehicles in Bolivia are powered by compressed natural gas. Through semi-structured interviews, questionnaires and secondary data collection, this paper elucidates the transitional process of building a natural gas-based transport network through discursive governance. This work draws on the critical discourse analysis literature to dissect disaggregated modal preference data, government documents, and news articles collected in Santa Cruz, Latin America's second fastest growing city. Moreover, this paper identifies and examines the ways in which the counter-discourse impacts the transformation of the country’s energy matrix. Results show that Bolivian automobile owners are reluctant to convert their automobiles, despite reduced transportation costs, stating that minimal compressed natural gas infrastructure exists outside of urban areas, and the conversion damages their vehicles’ motor. Additionally, the research reveals that automobile owners are currently the main beneficiaries, though respondents who do not posses an automobile speak more favorably of natural gas. Finally, this research illustrates that the compressed natural gas-oriented policies encourage personal automobile use that continues to drive socio-spatial segregation of Santa Cruz’s residents. Thus, the compressed natural gas discourse helps shape the urban landscape by persuading the public to consume domestically extracted and manufactured natural gas.
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Biodiesel: análise e dimensionamento da rede logística no Brasil usando programação linear. / Biodiesel: supply chain analyses and facilities location using mixed integer linear programming.Carvalho, Éden de Rezende 18 September 2008 (has links)
Neste trabalho foi desenvolvido um modelo de programação linear inteira mista para localização das instalações da rede logística do biodiesel no Brasil, de forma a que se possa, com sua aplicação, avaliar o potencial de produção de oleaginosas no país, assim como identificar as zonas mais promissoras para a localização dos diversos elos da cadeia do biodiesel, a partir da demanda gerada pela mistura de um percentual de biodiesel ao diesel fóssil. O modelo incorpora quatro elos da cadeia produtiva (fase agrícola, extração de óleo, produção de biodiesel e pontos de demanda). Os parâmetros do modelo foram estimados com base em informações reais de mercado disponíveis (base de dezembro/2007). Obteve-se com a aplicação do modelo a diversos cenários, os municípios mais indicados para produção das oleaginosas, as oleaginosas utilizadas, o volume de produção em cada local e, por fim, a localização e porte das fábricas de óleo e das usinas de biodiesel. Análises de sensibilidade de alguns parâmetros foram executadas para verificação do comportamento do modelo face a incertezas. O trabalho incorpora sugestões e recomendações para aprimoramento do modelo. / In this research a mixed integer linear programming model was developed to locate facilities related to the biodiesel supply chain in Brazil, making possible to evaluate the oleaginous production potential, as well as the most promising regions to became the location of the several levels of the biodiesel chain, in accordance to the biodiesel future demand. The model incorporates four levels of the productive chain (agricultural phase, extraction of oil, biodiesel production and demand points). The model parameters were estimated based on market information available (base of december/2007). The application of the model to several sceneries led to the indication of the most promising regions for production of the oleaginous, the used oleaginous ones, the volume of production in each place and, finally, the location and scale of oil and biodiesel factories. Sensibility analyses were conducted to verify the results related to parameters uncertainty. The research contains suggestion and recommendations for improvement of the model.
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Análise do emprego de materiais alternativos no alto forno da Arcelormital Tubarão /Mosckem, Sergio Luis. January 2010 (has links)
Resumo: O trabalho de análise do uso de materiais alternativos no Alto Forno 1 da ArcelorMittal Tubarão estabelece uma taxa de substituição de cada material alternativo, plástico e pneu, em relação ao uso exclusivo do carvão mineral injetado no Alto Forno através das ventaneiras. A taxa de utilização de plástico e pneu é avaliada considerando o aporte de energia e dos agentes necessários para a reação química de redução do minério de ferro em ferro metálico. No presente trabalho são elaborados os balanços de massa e de energia de acordo com a configuração operacional vigente no segundo semestre de 2009 para o Alto Forno 1 e com os dados de produção do mês de julho de 2009. O resultado mostra a viabilidade técnica do uso de plástico ou pneu e estabelece as condições de uso de cada um em relação à quantidade, tipo e granulometria. A substituição energética decorrente do uso de plástico e pneu estabelece uma forma de aplicação segura e controlada deste resíduo, além de agregar valor a estes materiais normalmente descartados pela sociedade. Contribui também para amenizar os impactos ambientais decorrentes da falta de uma destinação regulamentada e eficaz para plásticos descartados e pneus inservíveis / Abstract: The study of alternative fuel materials in the Blast Furnace 1 of ArcelorMittal Tubarão, establishes a rate of each material analyzed, waste plastics packaging and waste tires, in order to replace part of the pulverized coal that is usually injected in to the Blast Furnace through the tuyeres. The injection rate of waste plastic packaging and waste tires is analyzed considering the energy input and the necessary elements for the iron ore reduction chemical reaction. The mass and energy balance is done according to the operational configuration of the Blast Furnace 1 in the second semester of 2009 and operation data from July of 2009. The result of the study shows technical viability to use waste plastics packaging and waste tires and establish requirements for the injection, such as flow rate and particles size. The alternative energy provided from these waste materials builds a safety and controlled way to reach the best utilization for each one. Moreover, the environmental impact can be reduced due to its disposal is normally done in outdoor areas / Orientador: José Antonio Perrella Balestieri / Coorientador: João Andrade de Carvalho Junior / Banca: Luiz Roberto Carrocci / Banca: Ricardo Dias Martins de Carvalho / Mestre
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Prospecção e bases de formação da demanda e oferta de etanol combustível nos Estados Unidos / Prospection and formation basis of supply and demand for ethanol fuel in the United StatesIshikawa, Aline 03 December 2013 (has links)
Desde o primeiro choque do petróleo, em 1973, os países têm despendido esforços para reduzir sua dependência pelo produto, produzido principalmente em regiões politicamente instáveis. Os Estados Unidos são os maiores consumidores mundiais do combustível, e cerca de 70% são destinados ao transporte. Desde o final da década de 70, o governo americano tem incentivado o uso de etanol como substituto parcial da gasolina. No entanto, o crescimento do biocombustível levantou polêmicas porque a matéria-prima utilizada na sua produção no país é o milho, o que poderia estar afetando a oferta do grão para a produção de alimentos. Dessa forma, foi aprovado em 2007 o RFS2, uma legislação que prevê o consumo mandatório de volumes crescentes de etanol até 2022, mas limita a produção a partir de milho. Os investimentos em pesquisas de combustíveis alternativos passaram a se focar no desenvolvimento de etanol de segunda geração, que utiliza material celulósico como matéria-prima. Sua viabilidade técnica já foi confirmada, mas ainda são necessárias melhorias no processo de produção para que o produto possa ser ofertado em escala comercial. Por outro lado, o Brasil tem uma indústria de etanol madura e também tem feito pesquisas na tecnologia de segunda geração. Se bem sucedida, o país tem planos de exportar o excedente de produção, e os Estados Unidos são um mercado de interesse. O objetivo desta dissertação é auxiliar na avaliação das necessidades de os Estados Unidos importarem etanol de outros países, o que pode criar uma oportunidade para o Brasil. Para isso, foi utilizada a abordagem lógico-intuitiva de construção de cenários - voltada a aspectos qualitativos - para estudar o mercado de etanol combustível nos Estados Unidos até o ano de 2022. A coleta de informações foi feita por meio da revisão bibliográfica, focada em artigos internacionais. A política energética americana e a evolução da tecnologia de segunda geração de etanol foram identificadas como as principais incertezas que devem moldar o futuro do mercado em estudo. A partir delas, foram gerados quatro cenários, nomeados como \"Filho pródigo\", \"Pais esperançosos\", \"Filho independente\" e \"Filho preterido\". Concluiu-se que, enquanto o governo americano continuar incentivando o consumo de etanol, haverá boas oportunidades de exportação do biocombustível brasileiro. Os maiores volumes são esperados em \"Pais esperançosos\". Por outro lado, caso outras alternativas energéticas sejam priorizadas, nossas exportações podem reduzir substancialmente, e o volume comercializado dependerá do preço do nosso produto em relação ao deles e à gasolina. / Since the first oil shock in 1973, countries have made efforts to reduce their dependence on the product, mainly produced in politically unstable regions. The United States is the world\'s largest consumer of the fuel, and about 70 % is allocated to transport. Since the late 70s, the U.S. government has encouraged the use of ethanol as a partial substitute for gasoline. However, the growth of the biofuel arose controversy because the raw material used for the domestic production is corn, which could be affecting the supply of the grain for food production. Thus, it was approved in 2007 the RFS2, a legislation that requires mandatory use of increasing volumes of ethanol until 2022, but limits production from corn. Investments in alternative fuels research started to focus on the development of second generation ethanol, which uses cellulosic material as feedstock. Its technical feasibility has been confirmed, but improvements are still needed in the production process so that the product can be offered on a commercial scale. On the other hand, Brazil has a mature ethanol industry and is also doing research on second-generation technology. If successful, the country plans to export the surplus production, and the United States is a market of interest. The objective of this thesis is to assist the assessment of the United States needs to import ethanol from other countries, which may create an opportunity for Brazil. The logical-intuitive approach of scenario building - focused on qualitative aspects - was used to study the market for fuel ethanol in the United States until the year 2022. Data collection was done through literature review, focused on international articles. The U.S. energy policy and developments in the technology of second generation ethanol were identified as the major uncertainties that are shaping the future of the market under study. Four scenarios were generated from these two uncertainties and named as \"Prodigal Son\", \"Hopeful parents\", \"Independent Son\" and \"Deprecated Son\". It was concluded that while the U.S. government continues to encourage the consumption of ethanol, there are good opportunities to export the Brazilian biofuel. The largest volumes are expected in \"Hopeful parents\". On the other hand, if other energy alternatives are prioritized, our exports can reduce substantially, and sales volume will depend on the price of our product relative to theirs and gasoline.
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