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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.
621

O gás natural como alternativa energética para a indústria têxtil: vantagem competitiva ou estratégia de sobrevivência? / Natural gas as energy alternative to textile industry: competition advantage or survival strategy?

Lima, Mariana Sarmanho de Oliveira 28 February 2007 (has links)
Diante da crise energética que o Brasil enfrentou nos anos de 2000/2001, as empresas passaram a procurar novas alternativas de energia visando manter o nível de produção. Uma alternativa capaz de fazer a substituição da energia elétrica e de outras fontes energéticas consideradas nocivas ao meio ambiente e, de ao mesmo tempo, proporcionar benefícios econômicos, operacionais, ambientais e até de qualidade do produto para as empresas consumidoras parece ser a utilização do gás natural (GN). O presente trabalho identifica os fatores que interferem na adoção do gás natural como energético alternativo em empresas da indústria têxtil da região administrativa de Campinas (SP) e verifica a viabilidade tanto em termos econômicos quanto estratégicos de projetos de investimento desta natureza. Para isso, são realizadas pesquisas descritivo-exploratórias e um estudo de caso junto às empresas têxteis dessa região. O trabalho apresenta resultados tanto de caráter qualitativo como quantitativo que ajudam as empresas têxteis a decidir se adota ou não o GN em seus processos produtivos. É interessante destacar também que não foram encontrados, na literatura pesquisada, estudos semelhantes, o que demonstra a carência de pesquisas envolvendo o tema. O aporte teórico desta proposta está baseado na indústria têxtil, na importância do gás natural para a indústria, nas estratégias, na inovação tecnológica e na análise de investimento. / Due to the energy crisis Brazil faced in 2000/2001, companies started to look for new alternatives of energy in order to keep production level. An alternative capable to replace electric energy and other energy sources considered harmful to the environment and at the same time able to cause economic, operational, environmental, and even product-quality profits to consumer enterprises seems to be natural gas (NG). The current research identifies factors that interfere in the adoption of natural gas as an alternative energy source in textile industry located in Campinas (SP) and surroundings, as well as it analyses the viability both in economic and strategic terms of investments of this nature. For this purpose, a descriptive-exploratory research was done, in addition to a case-study of textile companies from that location. This research presents both qualitative and quantitative results, which will help textile companies decide if they will adopt NG or not on their productive processes. It is also interesting to emphasize that other similar studies were not found, which demonstrate a lack of research on this subject. The theoretical framework is based on textile industry, as well as on importance of natural gas to industry, strategies, technological innovation and on investment analysis.
622

Avaliação de um ciclo de liquefação usando a tecnologia de refrigerante misto para plantas de pequena escala de GNL. / Analysis of a liquefaction cycle using mixed refrigerant technology for LNG small scale plants.

Tacuse Begazo, Christian Daniel 14 November 2008 (has links)
Este trabalho tem como objetivo analisar a tecnologia do ciclo refrigerante misto para obtenção de gás natural liquefeito (GNL). Nessa tecnologia, o GNL é obtido por meio do seu resfriamento através de um ciclo de refrigeração, cujo fluido refrigerante é formado por uma mistura de diversos componentes. O ciclo de refrigeração é usado para resfriar a corrente de gás natural até as condições criogênicas por meio de um trocador de calor. A determinação da composição ótima dessa mistura de refrigerantes é de suma importância para a correta e eficiente operação da planta. O modelo termodinâmico para o cálculo de equilíbrio de fases dos componentes da mistura refrigerante é o baseado na Lei de Raoult, válido para misturas e soluções ideais. Inicialmente, revisam-se os conceitos de refrigerantes mistos, curvas compostas e o ponto de pinça (pinch point), utilizados na implementação da solução computacional. A aplicação dos modelos de gás e solução ideal influencia nos resultados, mas, não obstante, produz bons resultados como os obtidos no presente trabalho. A operação eficiente do ciclo depende, sobretudo, de três parâmetros principais, quais sejam: vazão da mistura refrigerante, razão de pressões alta e baixa do ciclo de refrigeração e composição da mistura refrigerante. Da análise dos resultados obtidos conclui-se que a alteração nas proporções da composição do refrigerante muda significativamente a forma das curvas composta quente e composta fria, quando comparados à alteração dos níveis de pressão e da vazão do ciclo refrigerante. Entretanto, a operacionalização do ciclo somente ocorre se um dado conjunto de valores daqueles parâmetros satisfaça uma determinada diferença mínima de temperatura, ou ponto de pinça, entre as curvas composta quente e composta fria dentro do trocador de calor. Assim, a operação eficiente do ciclo de refrigeração requer a otimização daqueles três parâmetros operacionais. / This work has the objective of analyzing the technology of mixed refrigerant cycle for obtaining liquefied natural gas (LNG). In that technology, the liquefied natural gas is obtained by means of cooling through a refrigeration cycle, whose fluid refrigerant is formed by a mixture of various components. The refrigeration cycle is used to cool the natural gas stream to cryogenic condition with the use of a heat exchanger. The determination of the optimal composition of this refrigerant mixture is very important for the correct and efficient operation of the plant. The thermodynamic model for the equilibrium phase calculation of the refrigerant mixture is based on the Law of Raoult, which is valid for ideal mixtures and solutions. Initially, the concepts of refrigerant mixture, composite curves and pinch point used in the implementation of the numerical solution were reviewed. The application of ideal-gas and ideal-solution models has influence on the results. Nevertheless, it produces good results as those obtained in the present work. The efficient operation of the cycle depends essentially of three key parameters, which are: refrigerant flow rate, the ratio of high to low pressures of the refrigerant cycle and the mixed refrigerant composition. The results indicated that the composition variation of the refrigerant changes significantly the shape of hot and cold composite curves in comparison to the modification in the pressure levels and the refrigerant flow rate of the refrigerant cycle. However, the process will operate only if a given set of values of those parameters satisfies a minimum temperature difference, or pinch point, between the hot and cold composite curves within the heat exchanger. Thus, the efficient operation of the refrigerant cycle requires the optimization of those three operational parameters.
623

Avaliação da inserção do gás natural no setor industrial brasileiro: uma análise de indicadores de impactos energético, ambiental e econômico. / Evaluation of the Natural Gas Insertion in the Brazilian Industrial Sector An Assessment of Energy, Environmental and Economic Impact Indicators.

Gallo, Alexandre de Barros 31 January 2018 (has links)
O paradigma atual do uso da energia no setor industrial brasileiro é fruto da conjuntura histórica do setor energético no país e permite explicar algumas de suas características particulares, a utilização intensiva de eletricidade em processos térmicos, a eletrotermia, algo que perdura até hoje. O cenário nacional de produção de gás natural é promissor, no contexto do Pré-Sal, o que sinaliza uma oportunidade para aplicar esse recurso natural para usos energéticos com maior valor agregado, como por exemplo como energia final para a indústria. É neste contexto que se insere esta dissertação onde foi desenvolvida e aplicada uma técnica de análise de dados com objetivo de avaliar a inserção do gás natural no setor industrial brasileiro e seus impactos. A técnica de análise de dados desenvolvida constitui-se na avaliação de quatro indicadores: Demanda Adicional (DA); Impacto em Energia Primária (IEP); Impacto em Emissões de Carbono (IEC) e Impacto em Custo Energético (ICE). Nos resultados obtidos, o Setor de Metais Não-Ferrosos teve maior destaque ao apresentar a maior demanda adicional por gás natural e as maiores reduções em demanda de energia primária, emissões de CO2 e custo energético. Outros setores que se destacaram foram o Setor de Ferro e Aço e Setor de Alimentos e Bebidas. Tomando 2013 como ano-base, a demanda adicional por gás natural resultante da substituição de óleo combustível e eletricidade em processos térmicos representaria um aumento entre 37% a 42% na demanda de gás natural no setor industrial brasileiro, equivalente a 12% a 14% da oferta interna de gás natural no Brasil, ou ainda 35% a 40% da capacidade máxima do Gasbol. O impacto em energia primária representaria uma redução de 1% a 2% da demanda de energia primária do setor industrial brasileiro. O impacto em emissões de CO2 representaria uma redução de 4% a 5% das emissões de CO2 associadas ao uso de energia do setor industrial brasileiro. O impacto em custo energético representaria uma redução de 2% a 4% dos custos energéticos associados a eletricidade e óleo combustível do setor industrial brasileiro. Assim, considera-se que existe uma oportunidade de inserção do gás natural no setor industrial brasileiro resultante da substituição de óleo combustível e eletricidade por gás natural em processos térmicos. De forma geral, seus impactos reduzem a demanda de energia primária, as emissões de CO2 e o custo energético. Entretanto, trata-se de uma iniciativa de economia de energia via substituição energética, desse modo, ressalta-se necessidade de se fomentar a eficiência energética, para todos os usos finais e tipos de energia final em uso, de modo a se obter um maior impacto em termos de redução no consumo de energia e mitigação de emissões, dois elementos importantes no debate atual sobre combate a mudanças climáticas. / The present energy use structure in the Brazilian industrial sector is a consequence of its historical context within the Brazilian energy sector. This historical background helps to explain some characteristics, like the intensive use of electricity in heating processes, the electrothermia, that lasts until today. The current natural gas production scenario in Brazil is promising, considering the Pre-Salt production, which signals an opportunity to apply this natural resource to final energy uses with higher value, such as final energy for industry. In this context was structured this dissertation, comprising a data analysis technique development and its application to evaluate the insertion of natural gas in the Brazilian industrial sector and its impacts. The developed data analysis technique is constituted by the assessment of four indicators: Additional Demand (DA); Impact on Primary Energy (IEP); Impact on Carbon Emissions (IEC) and Impact on Energy Cost (ICE). In the results obtained, the Non-Ferrous Metals Sector was more prominent as it presented the greater additional demand for natural gas and the largest reductions in primary energy demand, CO2 emissions and energy costs. Other sectors that stood out were the Iron and Steel Sector and the Food and Beverages Sector. Considering 2013 as the base year, the additional demand for natural gas resulting from the substitution of fuel oil and electricity in heating processes would represent a 37% to 42% increase in the demand for natural gas in the Brazilian industrial sector, equivalent to 12% to 14% of Brazil\'s domestic natural gas supply, or 35% to 40% of Gasbol\'s maximum capacity. The impact on primary energy would represent a reduction of 1% to 2% of the primary energy demand of the Brazilian industrial sector. The impact on CO2 emissions would represent a reduction of 4% to 5% of the CO2 emissions associated to energy use of the Brazilian industrial sector. The impact on energy cost would represent a reduction of 2% to 4% of the energy costs associated with electricity and fuel oil of the Brazilian industrial sector. Thus, it is considered that there is an opportunity for the insertion of natural gas in the Brazilian industrial sector resulting from the substitution of fuel oil and electricity by natural gas in thermal processes. Overall, the substitution impacts reduce primary energy demand, CO2 emissions and energy costs. However, this is an energy-saving initiative through energy substitution, being necessary to further promote energy efficiency, for all end uses and types of final energy in use, to multiply the impacts in terms of reducing energy consumption and mitigating emissions, two important elements in the current debate on combating climate change.
624

Perspectivas estratégicas para grandes consumidores industriais frente às mudanças regulatórias com a inclusão do livre acesso às redes de distribuição de gás natural canalizado no Estado de São Paulo / Strategic insights for Large Industrial Consumers facing regulatory changes with the introduction of Open Access for the Local Natural Gás Distribution Network in the State of São Paulo.

Bruno Spagnuolo Burghetti 27 April 2010 (has links)
A análise competitiva é focada na indústria de gás, entendida na dimensão da(s) Distribuidora(s) e Comercializada(s). O principal objetivo da pesquisa é contribuir na identificação de propostas estratégicas para os grandes consumidores (indústrias). Observa-se que esses consumidores deverão enfrentar uma nova estrutura regulatória, que exigirá uma eventual migração de um mercado regulado para outro livre, após a introdução da regulamentação do livre acesso às redes de distribuição de gás natural no Estado de São Paulo. Além disso, caracterizam-se os possíveis ambientes de efetivação da abertura do mercado e do livre acesso, bem como de consolidação da figura da Comercializadora de gás natural. O trabalho demonstra a dificuldade de se estabelecer um ambiente de maior concorrência em indústrias que convivem com um agente econômico dominante e que pode influenciar todas as dimensões do modelo teórico das Seis Forças Competitivas (adaptado a partir de Michael Porter). São identificadas as tendências de oferta e demanda nos mercados de gás do Brasil e do Estado de São Paulo. Além disso, o trabalho dedica-se a extensiva apresentação de modelos estruturais e contratuais que caracterizam as indústrias de gás em diferentes momentos de evolução e maturação. Procura-se mostrar que a indústria gasífera brasileira, apesar de ainda precoce em seu desenvolvimento, já apresenta elementos típicos de mercados mais concorrenciais, tornando qualquer análise um exercício pouco trivial. As mudanças do ambiente regulatório das indústrias do gás no Brasil e no Estado de São Paulo são descritas em detalhe, com principal foco nas relações das atividades de Distribuição e Comercialização com as etapas anteriores da cadeia produtiva. Como resultado, a obra oferece estratégias alternativas para o posicionamento dos grandes consumidores industriais em um mercado ainda restrito em sua base concorrencial. / The competitive analysis is focused on the gas industry, understood as the Local Distribution and Marketing activities. The researchs main objective is to contribute to identify strategic insights for large industrial consumers. Those consumers will face a new regulatory framework, which will require them to an eventual migration from a regulated to a more competitive market after the introduction of the Open Access regulation in the local gas distribution network in the State of Sao Paulo. The text also characterizes the possible environments for an effective competitive market and open access as well as for the consolidation of gas marketers. The work demonstrates the difficulty in establishing a more competitive environment in industries coexisting with dominant economic agents, which can influence all the dimensions underlined by the Six Competitive Forces theoretical model (adapted from Michael Porter). It is identified the supply and demand trends in the gas markets of Brazil and the State of Sao Paulo. Moreover, the work contributes with an extensive presentation of structural models and contractual arrangements that characterize the gas industries in different development stages. The aim is to show that the gas industry in Brazil, although still in its early development, has features which are already typical from more competitive markets, turning any analysis into a nontrivial exercise. The changes in the regulatory environment of the gas industry in Brazil and in the State of Sao Paulo are described in detail, with main focus on the relations between the Distribution and Marketing activities vis-à-vis the previous steps of the supply chain. As a result, the work offers alternative strategies for the positioning of large industrial consumers in a market still restricted in its competitive basis.
625

Comércio de gás entre Brasil e Bolívia interesses e atores da nacionalização de 2006 / Natural gas trade between Brazil and Bolivia: interest and players of nationalization of 2006

Paulo Roberto Silva 08 March 2012 (has links)
A crise entre Brasil e Bolívia desencadeada pela nacionalização do gás é representativa do pa­pel da política doméstica nos temas das relações internacionais. Neste estudo, adotamos uma análise de escolha racional a partir do modelo da Economia Política Aberta, que parte do ambiente econômico para identificar interesses econômicos e sociais, como eles se materializam nas preferências políticas de atores sociais e econômicos, que influenciam a política doméstica e a atuação internacional do estado nacional. No caso em estudo, analisamos a interação e a barganha entre Brasil e Bolívia a partir da influência de atores como o movimento indígena-camponês boliviano, que acumulou forças ao longo dos anos e pôde impor sua agenda de nacionalização dos recursos naturais, a indústria de petróleo e gás, liderada pela Petrobras, e o empresariado industrial brasileiro, consumidor de 50% da oferta de gás natural brasileira. Estes atores influenciaram seus governos, que atuaram racionalmente para defender os interesses de seus países, considerados neste estudo como os interesses dos atores sociais e econômicos com maior força política. / The crisis between Brazil and Bolivia, triggered for the nationalization of natural gas, is rep­resentative of the role of domestic policy issues in international relations. In this study, we ad­opted an analysis of rational choice model, from Open Economy Politics, which starts from the economic environment to identify economic and social interests, and how they matter in political preferences of social and economic players, which influence the domestic politics and international acting of national state. In this case, we analyzed the interaction and bargaining between Brazil and Bolivia under the influence of players like Bolivian peasant-indigenous movement, which gains strength over the years and impose their agenda of nationalization of natural resources, oil and gas industry, led by Petrobras, and, last but not least, Brazil\'s industrial and business, consumer 50% of local supply of natural gas. These actor influenced their governments, who acted rationally to defend our national interests, considered in this paper as the interests of social and economic actors with strong political power.
626

Economic regulation of offer and demand of flexibility in gas network / L'économie de la reglementation de la flexibilité de l'offre et de la demande du transport gazier

Carvalho Metanias Hallack, Michelle 24 June 2011 (has links)
La thèse discute des conséquences des changements majeurs du modèle de la demande de gaz décrits précédemment. L´exigence de flexibilité à court terme a été l´une des principales caractéristiques de la demande de gaz pour la production d´électricité. Ainsi, la capacité de l´industrie du gaz à fournir des services flexibles à court terme a été valorisée par le biais du marché de l´électricité. Cela signifie une augmentation de la valeur économique des services permettant d´adopter une position attentiste vis-à-vis de la consommation avant toute prise de décision. Différents secteurs de l´industrie du gaz ont été affectés par les variations de la demande, c´est le cas de la production des champs de gaz, du stockage et des mécanismes d´importation du gaz qui ont été incités à la flexibilité. L´introduction des outils de flexibilité, qu’impliquent les variations de la demande, dépend directement des services de réseau. Par conséquent la concrétisation de la valeur économique de la flexibilité de l´industrie gazière dépend des services de réseau.Le réseau de transports de gaz est un élément-clé de l´industrie gazière portant sur deux types de flexibilités physiques: la mobilité et l´aptitude au stockage. Les propriétés physiques du gaz naturel permettent la flexibilité par la gestion des différentiels de pression. Les différentiels de pression contrôlent les mouvements de gaz. Le réseau est de loin le principal mécanisme de transport de gaz et donc un élément majeur de la filière du gaz permettant le commerce de cette matière première. Cependant, le réseau peut aussi être l´une des parties les plus couteuses de l´industrie gazière et, une fois les investissements réalisés ils ne sont ni remboursables, ni récupérables par un autre moyen car ils n'ont pas d’autres utilisations, ce sont les coûts irrécupérables. Malgré cela, la spécificité de le utilisation des actifs des réseaux évolue au cours du développement du réseau.L´intervention des réseaux de transport dans la prestation de services de flexibilité du gaz est une condition obligatoire de la flexibilité du système gazier. Premièrement parce que les services de réseau sont complémentaires de tout autre instrument de flexibilité tels que le stockage souterrain, les infrastructures GNL et le commerce de gaz. Deuxièmement, parce que les services du réseau de transport gazier, tel le que stock en conduite, peuvent également être compétitifs vis à vis d´autres instruments de flexibilité dégroupé.Par conséquent, la régulation du réseau doit prendre en compte l´impact à court et à long terme des règles d´incitation. Compte tenu du fait que le développement du réseau dépend des exigences de flux prévisibles, des variations importantes de la demande de gaz et les changements de flux qui en découlent auront un impact sur l´activité d´exploitation des réseaux gaziers. D´un côté le développement du réseau dépend de la prévision des besoins de flux, et de l´autre, la flexibilité des infrastructures du réseau conditionne nécessairement celle de l´utilisation. Par conséquent, les variations de la demande, responsable de l´accroissement des exigences de flexibilité ainsi que des variations des flux de gaz qui en découlent doivent avoir un impact sur l´exploitation du réseau de gaz et sur l´incitation aux investissements d’infrastructure. / This thesis discusses the consequences of the major changes in gas demand patterns. The requirement of short term flexibility has been one of the main features of electricity generation gas demand. As consequence, the capacity of gas industry to provide short term flexibility services has been valorized through electricity market. It means an increasing economic value to services allowing waiting and seeing before consumption decision. Different parts of the gas industry was impacted by the changes on demand, for instance gas fields productions, storage and gas importation mechanisms were incited to offer flexible provisions. The introduction of tools to provide flexibility required by demand depends on network services. It means the realization of the flexibility value of gas industry depends on gas network services. The gas transport network is the key part of gas industry, and it may provide two kinds of gas physical flexibility: mobility and storability. The physical properties of natural gas allow flexibility by means of pressure differential management. The change on pressures may compress natural gas and the pressures differences drive gas motions. The network has been, by far, the main mechanism to carry gas, thus an essential part of the gas industry chain to allow commodity trade. Network, however, may be one of the most expensive parts of gas industry, and, after the investment done, it becomes sunk costs. But the specificity of networks assets changes in the course of network development. The use of transport network in the provision of gas flexibility services is a necessary condition to provide flexibility in the gas system. First, because network services are complementary of any other flexibility tool, as underground storage, LNG infrastructures and gas trade. Second, because gas transport network services, as line-pack storage, may also be competitive to the others unbundled flexibility tools. Therefore, network regulation needs to take into account the short and the long term impact of the rules incentives. Given that network development depends on expected flow requirements, strong change on gas demand and the consequent changes on gas flows must impact gas network operation. On the one hand, network development depends on expected flow requirements, and on the other, provisions of flexibility depend necessarily on the flexible use of network infrastructures. Hence, changes on gas demand increasing flexibility requirements and the consequent changes on gas flow must impact gas network operation and must impact the incentive on infrastructures investment.
627

Allocation of natural gas in times of shortage : a mathematical programming model of the production, transmission, and demand for natural gas under Federal Power Commission regulation.

Brooks, Robert Eugene January 1975 (has links)
Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Alfred P. Sloan School of Management. / Vita. / Bibliography: leaves 240-250. / Ph.D.
628

A techno-economic and environmental analysis of a novel technology utilizing an internal combustion engine as a compact, inexpensive micro-reformer for a distributed gas-to-liquids system

Browne, Joshua Benjamin January 2016 (has links)
Anthropogenic greenhouse gas emissions (GHG) contribute to global warming, and must be mitigated. With GHG mitigation as an overarching goal, this research aims to study the potential for newfound and abundant sources of natural gas to play a role as part of a GHG mitigation strategy. However, recent work suggests that methane leakage in the current natural gas system may inhibit end-use natural gas as a robust mitigation strategy, but that natural gas as a feedstock for other forms of energy, such as electricity generation or liquid fuels, may support natural-gas based mitigation efforts. Flaring of uneconomic natural gas, or outright loss of natural gas to the atmosphere results in greenhouse gas emissions that could be avoided and which today are very large in aggregate. A central part of this study is to look at a new technology for converting natural gas into methanol at a unit scale that is matched to the size of individual natural gas wells. The goal is to convert stranded or otherwise flared natural gas into a commercially valuable product and thereby avoid any unnecessary emission to the atmosphere. A major part of this study is to contribute to the development of a novel approach for converting natural gas into methanol and to assess the environmental impact (for better or for worse) of this new technology. This Ph.D. research contributes to the development of such a system and provides a comprehensive techno-economic and environmental assessment of this technology. Recognizing the distributed nature of methane leakage associated with the natural gas system, this work is also intended to advance previous research at the Lenfest Center for Sustainable Energy that aims to show that small, modular energy systems can be made economic. This thesis contributes to and analyzes the development of a small-scale gas-to-liquids (GTL) system aimed at addressing flared natural gas from gas and oil wells. This thesis includes system engineering around a design that converts natural gas to synthesis gas (syngas) in a reciprocating internal combustion engine and then converts the syngas into methanol in a small-scale reactor. With methanol as the product, this research aims to show that such a system can not only address current and future natural gas flaring regulation, but eventually can compete economically with historically large-scale, centralized methanol production infrastructure. If successful, such systems could contribute to a shift away from large, multi-billion dollar capital cost chemical plants towards smaller systems with shorter lifetimes that may decrease the time to transition to more sustainable forms of energy and chemical conversion technologies. This research also quantifies the potential for such a system to contribute to mitigating GHG emissions, not only by addressing flared gas in the near-term, but also supporting future natural gas infrastructure ideas that may help to redefine the way the current natural gas pipeline system is used. The introduction of new, small-scale, distributed energy and chemical conversion systems located closer to the point of extraction may contribute to reducing methane leakage throughout the natural gas distribution system by reducing the reliance and risks associated with the aging natural gas pipeline infrastructure. The outcome of this thesis will result in several areas for future work. From an economic perspective, factors that contribute to overall system cost, such as operation and maintenance (O&M) and capital cost multiplier (referred to as the Lang Factor for large-scale petro-chemical plants), are not yet known for novel systems such as the technology presented here. From a technical perspective, commercialization of small-scale, distributed chemical conversion systems may create a demand for economical compression and air-separation technologies at this scale that do not currently exist. Further, new business cases may arise aimed at utilizing small, remote sources of methane, such as biogas from agricultural and municipal waste. Finally, while methanol was selected as the end-product for this thesis, future applications of this technology may consider methane conversion to hydrogen, ammonia, and ethylene for example, challenging the orthodoxy in the chemical industry that “bigger is better.”
629

Avaliação global dos modos energéticos de transporte do gás natural inclusive como energia secundária / Global Evaluation of Energy Ways of Natural Gás Transport, as Well as Secondary Energy

Rigolin, Pascoal Henrique da Costa 15 June 2007 (has links)
O objetivo do trabalho é fazer a avaliação global de alguns dos modos energéticos de transporte do gás natural (gasodutos, GNL e GNC), inclusive como energia secundária (eletricidade e GTL). Para a escolha do melhor modo de transporte, além dos custos de cada projeto, serão considerados outros três fatores, que são: impactos ambientais, impactos sociais e riscos políticos. Para isto foi escolhida uma ferramenta de análise conhecida como Avaliação de Custos Completos (ACC), sendo que esta considera os quatro fatores citados anteriormente como de mesma importância na avaliação para um planejamento que vise a sustentabilidade. Para melhor visualização e entendimento do trabalho, foi feito um estudo de caso para o transporte de energia (gás natural e/ou eletricidade) para atender mercados consumidores na região de fronteira entre o Brasil e a Bolívia. Fundamentalmente o estudo do transporte foi feito em solo boliviano, correspondente entre os campos produtores de gás, localizados em Margarita, até a região de fronteira próxima a Corumbá no Mato Grosso do Sul (MS), e também próxima a uma região com grandes jazidas de minério de ferro conhecida como El Mutún. Metodologicamente dentro das quatro dimensões consideradas, foram usados alguns subcritérios mais relevantes para esta análise. Para todos os sub-critérios foram atribuídas notas específicas, de acordo com a região e com o tipo de transporte de energia, e após isto os dados foram passados para um software de tomada de decisão chamado Decision Lens, obtendo assim um rank das melhores opções transporte para a região. Como resultado, o mais coerente para atender a região, são gasodutos de transporte para as demandas elétricas e de gás natural (consumo do MS mais Mutún) e trens carregados com derivados líquidos do gás natural (GTL) para atender a demanda de diesel do MS. / The objective of this work is to make a global evaluation of some energy ways of transport of natural gas (gas-pipelines, LNG and CNG), as well as secondary energy (electricity and GTL). For the selection of a better way of transport, beyond the costs of each project, others three factors were considered: environmental impacts, social impacts and political risks. To perform this, a tool of analysis known as Evaluation of Complete Costs (ACC in portuguese) was chosen. This tool considers the four factors above mentioned as having the same importance in the evaluation process for planning that aims towards sustainability. For better visualization and understanding of the work, a case study for energy transport was made (natural gas and/or electricity) to supply the consumer markets in the region bordering Brazil and Bolivia. Basically the study of the transport was made in Bolivian territory; at the producing gas fields located in Margarita as far as the region bordering Corumbá in the Mato Grosso do Sul area, and also next to a region with great known iron ore deposits known as El Mutún. Methodologically, within the four dimensions above, some more relevant sub-criteria for the analysis were used. For all the sub-criteria considered specific ranks were taken, in accordance with the region and type of transported energy, and after this the data was fed to a software called Decision Lens, thus getting a rank of the best options to carry gas to the region. The results, most coherent way to supply gas to the region, happens to be gas-pipelines of transport for the electric and natural gas demands (consumption in MS plus Mutún) and trains with liquid derivatives of natural gas (GTL) to supply care of the demand of diesel of MS.
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Desafios e oportunidades da geração eólica e termelétrica a gás natural no Sistema Elétrico Peruano. / Challenges and opportunities of the wind generation and to natural gas thermal in the Peruvian Electricity System.

Alvarez Lupaca, Wilbert Demetrio 08 February 2012 (has links)
Vários países ao redor do mundo têm procurado cada vez mais diversificar suas matrizes elétricas com o objetivo de diminuir a dependência de combustíveis fósseis e reduzir as emissões dos gases responsáveis pelo agravamento do efeito estufa na atmosfera. Com isso, tem crescido a participação de algumas fontes renováveis de energia que, até duas décadas atrás, não ocupavam lugar de destaque na matriz elétrica mundial, como por exemplo, a energia eólica. O gás natural, embora seja um recurso fóssil, é considerado menos poluente e este tem substituído os derivados de petróleo em várias aplicações, entre elas na geração de eletricidade. O Peru, no intuito de atender a sua demanda crescente por eletricidade, vem buscando novas alternativas energéticas, como por exemplo, a energia eólica e, em maior escala, a termeletricidade com o uso do gás natural, cuja disponibilidade aumentou consideravelmente após o início da exploração das jazidas de Camisea. O presente trabalho tem o objetivo de avaliar, tanto em um cenário de curto prazo como de longo prazo, o impacto de uma maior inserção da energia eólica e a expansão das térmicas a gás natural na operação econômica do sistema hidrotérmico Peruano. Esta avaliação é realizada com base na análise das seguintes figuras de mérito: custo marginal de operação (CMO), custo de operação do sistema, deslocamento de geração térmica e perfil de despacho de geração das unidades geradoras (MWh). Foram realizadas simulações do sistema elétrico peruano com e sem participação da geração eólica e a partir dos resultados obtidos, efetuou-se uma análise comparativa com base nos cenários propostos. Para efetuar as simulações foi utilizada a ferramenta computacional denominada PERSEO. Este programa, utilizado pelo setor Elétrico Peruano, permite simular o sistema hidrotérmico com característica de representação de um sistema multi-reservatório, multi-nodal e multi-cenário utilizando programação dinâmica estocástica. O trabalho também apresenta as principais características do Setor Elétrico Peruano enfocando sua evolução, desafios e plano de expansão, onde, com base neste se elaborou as simulações propostas. Os resultados obtidos com a inserção da geração eólica, baseados nas premissas e cenários propostos, foram considerados positivos. Houve uma diminuição média anual de 18% nos custos marginais de operação, o que representa uma diminuição nos custos de operação em torno de US$ 28 milhões ao ano, ou seja, 4% do total. Com relação à geração térmica a gás natural, o impacto da maior inserção desta no sistema também foi positivo, com redução dos custos de operação do sistema e deslocamento de geração térmica mais poluente (óleo combustível e carvão mineral). Adicionalmente efetuou-se uma análise do potencial de complementaridade da geração eólica e hídrica e do plano de expansão da geração hídrica com exportação de energia elétrica para o Brasil. / Several countries around the world have increasingly sought to diversify their electrical matrix in order to reduce dependence on fossil fuels and reduce emissions of gases responsible for worsening greenhouse effect in the atmosphere. As a result, has grown the participation of some renewable energy sources that until two decades ago did not occupied a prominent place in the world energy matrix, such as wind power. The Natural gas, although it is a fossil resource, is considered less pollutant and it has replaced petroleum products in various applications among them in the generation of electricity. The Peru, in order to meet its growing demand for electricity, has been seeking new alternatives between them wind power, and on a larger scale, thermoelectricity with the use of natural gas whose availability has increased considerably since the beginning of the exploitation of the fields of Camisea. This study has the objective of evaluate, both in a short-term outlook and long-term the impact of a greater insertion of wind energy and expansion of natural gas thermal on the economic operation of the hydrothermal Peruvian system. This evaluation is performed based on the analysis of the following arguments of merit: the marginal cost of operation (CMO), cost of system operation, displacement of thermal generation and profile and generation dispatch of generating units (MWh). Simulations of Peruvian electric system \"with\" and \"without\" participation of wind generation were realized and from the results obtained, it was performed a comparative analysis based on the proposed scenarios. To effectuate the simulations, it was used a computational tool called PERSEO. This program, used by the Peruvian electricity sector, allows simulating the hydrothermal system with features of a representation of system multi-reservoir, multi-nodal and multi-scenario using stochastic dynamic programming. The study also presents the main characteristics of the Peruvian Electric Sector focusing on its evolution, challenges and expansion plan, where, based on this proposal were elaborated the simulations. The results obtained with the insertion the wind generation, based on premises and proposed scenarios, were considered positive. There was an average annual decline of 18% in the marginal costs of operation, which represents a decrease in operating costs around U.S. $ 28 million a year, i.e. 4% of the total. With respect to natural gas thermal generation, the impact of greater insertion of this in the system was also positive, with reduction the cost system operation and displacement of more polluting thermal generation (fuel oil and coal). Additionally it was performed an analysis of the complementarity potential of generation wind and hydro and of the plan for expansion of hydro power with electrical energy export to Brazil.

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