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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.
161

Analysis of hydraulic fracture propagation in fractured reservoirs an improved model for the interaction between induced and natural fractures /

Dahi Taleghani, Arash. January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2009. / Title from PDF title page (University of Texas Digital Repository, viewed on Sept. 10, 2009). Vita. Includes bibliographical references.
162

Vapor-liquid equilibria of natural gas-crude oil systems,

Standing, Marshall Burton, Katz, Donald La Verne, January 1900 (has links)
Abstract of Thesis (PH. D.)--University of Michigan, 1941. / An article, by M.B. Standing and D.L. Katz, reprinted from Petroleum technology, November 1943.
163

Crosslinked hollow fiber membranes for natural gas purification and their manufacture from novel polymers

Wallace, David William, Koros, William J., Paul, Donald R. January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisors: William J. Koros and Donald R. Paul. Vita. Includes bibliographical references.
164

Evaluation of the selective NOx recirculation technique using activated carbon

Zimmerman, Andrew James. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains viii, 52 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 45-47).
165

Μηχανιστική και κινητική μελέτη της μερικής οξείδωσης του μεθανίου προς αέριο σύνθεσης σε υποστηριζόμενους καταλύτες Ru

Ελμασίδης, Κωνσταντίνος 18 December 2009 (has links)
- / -
166

Modelagem e simulação de sistemas de geração de energia para o setor de petróleo e gás

Ernst, Mario Alberto Basulto [UNESP] January 2004 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2004Bitstream added on 2014-06-13T18:07:20Z : No. of bitstreams: 1 ernst_mab_dr_guara.pdf: 1070921 bytes, checksum: ae273e66978a6fbbebf387c55e60a66f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Neste trabalho é definido um cenário de transição entre o uso da energia proveniente de combustíveis fósseis e a utilização ainda restrita de certas fontes renováveis, como as biomassas, em especial, uma vez que o emprego de recursos hídricos e eólicos é dependente da sua disponibilidade, e tecnologias de aproveitamento da energia solar ainda demandam aperfeiçoamentos tecnológicos. Durante essa transição cabe otimizar os ciclos tradicionais que consomem óleo diesel e gás natural, visando diminuir o impacto nas reservas e no meio ambiente, aumentando o tempo disponível para a mudança, caso seja necessário. Após uma descrição dos ciclos avançados mais conhecidos é analisado de forma mais detalhada a utilização do ciclo com injeção de vapor (STIG) utilizando gás natural, em duas plantas processadoras de gás natural, incluindo uma comparação com o ciclo Rankine e Brayton convencionais. Esta análise é principalmente focado em Unidades de Compressão de gás natural, visto a grande ênfase que vêm sendo dada à sua utilização, trazendo como conseqüência a necessidade da extensão das redes de gasodutos. Os ciclos são analisados operando nas condições de projeto e com carga parcial ou sobrecarga, motivo pelo qual são formulados modelos termodinâmicos que são apresentados integrados a programas computacionais, considerando a maior quantidade de informações que permitam uma simulação próxima da realidade. Na simulação são considerados os custos de combustíveis e equipamentos, manutenção e, de forma simplificada, os ganhos potenciais provenientes da venda de créditos de carbono. Os objetivos propostos neste trabalho incluem a criação de modelos termodinâmicos para os ciclos estudados e sua simulação, considerando a operação com carga parcial, disponibilizando os dados utilizados de forma organizada... . / This work considers a transition scenario from fossil combustible energy and the restrict usage of renewable sources, specially biomass, just because water and eolic sources depend on their availability, and solar energy usage depends on technological improvements . During this transition, it is important to optimize traditional cycles that use diesel oil and natural gas, for minimizing the impact on natural reserves and environment, increasing the existing time schedule for changes, if necessary. After describing some advanced cycles, this study evaluates in more detail the usage of steam injection cycle (STIG) burning natural gas, applicable to two natural gas production plant, considering the comparison between Rankine and Brayton conventional cycles. This analysis is focused mainly in natural gas Compression Units due to the great emphasis that it has nowadays, with the necessity of increasing the gas pipeline. In this thesis, the cycles are analyzed considering the project part-load and over-load conditions, explaining why there are thermodynamic modeling to be integrated to computer programs to generate informations for a simulation closer to the real operational condition. In the simulation fuel and equipment prices, maintenance costs and, in a simple way, the potential return of investments coming from carbon dioxide credits sales were considered. Proposal goals from this study include new thermodynamic modelling applicable to the studied cycles and its simulation, considering partial load operation, offering the sparse technical and economic data in an organized way. After ending the study it was possible to conclude that the part load operation must be considered and that the oil and gas installation have a potential in energy savings.
167

Análise de um sistema de cogeração empregando turbina a gás aplicada a uma indústria de malte

Carvalho, Marcelo Bergamini de [UNESP] 04 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-04Bitstream added on 2014-06-13T20:39:47Z : No. of bitstreams: 1 carvalho_mb_me_guara.pdf: 1667182 bytes, checksum: 466e1d7987c5db03c6d55f35bb29386b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Neste trabalho analisa-se a viabilidade técnica e econômica da instalação de sistemas de cogeração, com emprego de turbinas a gás e dois diferentes tipos de trocadores de calor: um utilizando vidro e o outro convencional. Os sistemas são aplicados em uma indústria de transformação de cevada em malte, de médio porte, localizada no Vale do Paraíba. Para cada tipo de tecnologia empregada, seja por operação em paridade elétrica ou térmica, seleciona-se diferentes turbinas comercialmente disponíveis no mercado. Os resultados demonstram que existe viabilidade técnica e econômica para o emprego desta tecnologia na referida indústria. O período de amortização do capital investido é relativamente pequeno em relação à vida útil dos equipamentos empregados. PALAVRAS-CHAVES: Cogeração, Gás Natural, Conservação de Energia, Turbina a Gás. / The purpose of this work is to analyses the technical and economic feasibility to install cogeneration systems, using gas turbine associated with two different kinds of heat exchanger: the first utilize glass heat exchanger and second utilize conventional heat exchanger. These systems are being applied in medium sized barley transformation industry into malt located in Vale do Paraíba . To each kind of technology, is made a comparison in cogeneration operating in electric parity or thermal parity. Different turbines commercially available are chosen. The results show that there are technical and economic feasibility to make use of this technology in the industry in question. The pay-back period of investment is determinate as a function of annual interest rate, electricity tariff and fuel price. Key Words: Cogeneration, natural gas, energy conservation, Gas turbines.
168

Redução de assimetria de informação na revisão tarifária da distribuição de gás canalizado no Brasil: proposta de uma metodologia baseada na análise da geração de valor / Reduction of Asymmetry of Information in the Tariff Revision in the Brazilian Pipeline Gas Distribution: Proposal for a Methodology through Value Generation Analysis

Fernando Mario Rodrigues Marques 19 June 2009 (has links)
A tarefa de regular um mercado estruturado sob a forma de monopólio natural, como no caso da distribuição de gás canalizado no Brasil, implica assegurar o equilíbrio econômicofinanceiro das firmas reguladas, garantindo, ao mesmo tempo, modicidade tarifária e nível de excelência na qualidade dos serviços prestados. Para isso, a questão da formação de preços é crítica, pois envolve aspectos do excedente e sua distribuição. Por esta razão, dentre as atribuições do órgão regulador, destaca-se o estabelecimento de regras tarifárias que conciliem os interesses dos consumidores e da empresa regulada. Entretanto, a tarefa de desenhar tarifas justas é afetada pela assimetria de informações entre o órgão regulador e a firma regulada, em favor da última. Este trabalho sugere a incorporação da metodologia do Economic Value Added EVA® no processo de revisão tarifária. Tal incorporação, conforme demonstrado, permite ao regulador avaliar a geração de valor do setor e reduzir a assimetria informacional entre concessionárias e agência reguladora. Além disso, facilita o repasse de eventuais excessos de geração de valor aos consumidores, em benefício da sociedade. Palavras-chaves: Assimetria de informação, Economic value added (EVA®), gás canalizado, gás natural, geração de valor, revisão tarifária. / Regulating a structured market under natural monopoly such as the Brazilian pipeline gas distribution implies in assuring an economic and financial equilibrium of the regulated firms as well as guaranteeing the tariff moderateness and service quality excellence. In order to achieve this pricing is crucial, for it encompasses surplus and surplus distribution. Therefore, the role of setting tariff rules of the regulator agency, stands out so that these rules conciliate the interests of both consumers and the regulated companies. However, outlining fair tariffs is impacted by asymmetrical information between regulator agency and regulated firms in favor of the latter. This study suggests incorporating the Economic Value Added methodology in tariff revision process. This incorporation allows the regulator to evaluate the value generation in the sector and to reduce asymmetrical information between companies regulated and the regulator. In addition to this, it makes it easier to allocate the possible value generation surplus to the consumers in favor of the society. Key words: Asymmetrical information, economics regulation, tariff revision, value generation, economic value added (EVA®), natural gas, and pipeline gas.
169

A expansão do sistema de distribuição de gas natural no Brasil : a dinamica dos investimentos, da renda e das emissões de CO2 / The expansion of the system of natural gas distribuition in Brazil: the dynamics of the investments, the income and the emissions of CO2

Melo, Conrado Augustus de 24 February 2005 (has links)
Orientador: Sinclair Mallet-Guy Guerra / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-04T09:30:32Z (GMT). No. of bitstreams: 1 Melo_ConradoAugustusde_M.pdf: 9829134 bytes, checksum: fd6457ae9df47403660eda3893d89e8a (MD5) Previous issue date: 2005 / Resumo: No Brasil existe a expectativa de aumento da participação do gás natural na matriz energética. Contabilizar os investimentos necessários à viabilização desse aumento, a renda potencial gerada com a comercialização do gás natural e as emissões de 'C¿¿O IND. 2¿, permite o balizamento da tomada de decisões e do planejamento estratégico proporcionando o desenvolvimento sustentável. Utilizando a metodologia de sistemas dinâmicos procura-se nesse trabalho projetar o comportamento dessas variáveis indicando os futuros possíveis e os pontos chaves para direcionamento dessa expansão; analisa-se o caso brasileiro e o caso específico do Mato Grosso do Sul. Verifica que existe a necessidade de uma constante projeção da matriz energética, que a renda gerada pela comercialização é suficiente para a efetivação do acréscimo da infraestrutura de distribuição e que a redução das emissões de 'C¿O IND. 2¿ é viável através da substituição da lenha e do óleo combustível por gás natural / Abstract: In Brazil the expectation of increase of the participation natural gas in the matrix energy exists. To analyze the necessary investments to the viabilization of this increase, the potential income generated with the commercialization of the natural gas and the 'C¿¿O IND. 2¿ emissions, allows the measurement of the decisions taking and the strategical planning providing the sustainable development. Using the methodology of dynamic systems the study projects the behavior ofthese variable indicating the possible futures and the key points for aiming of this expansion. It analyzes the Brazilian case and the specific case of the "Mato Grosso do Sul". Verify the necessity of a constant projection of the matrix energy, that the income generated by the commercialization would be enough for the effectuation of the increase of the distribution infrastructure and that the 'C¿¿O IND. 2¿ emission could be less through replace between firewood and oil BPF by natural gas / Mestrado / Politica Energetica / Mestre em Planejamento de Sistemas Energéticos
170

Deuterium as a Quantitative Tracer of Enhanced Microbial Coalbed Methane Production

Ashley, Kilian, Ashley, Kilian January 2017 (has links)
Microbial production of natural gas in subsurface organic-rich reservoirs (e.g. coal, shale, oil) can be enhanced by the introduction of limiting nutrients to stimulate microbial communities to generate “new” methane resources on human timescales. The few successful field experiments of Microbial Enhancement of Coalbed Methane (MECoM) relied on relatively qualitative approaches for estimating the amount of “new” methane produced during the stimulation process (i.e. extrapolation of pre-stimulation gas production curves). We have tested deuterated water as a tracer, initially in the laboratory, to more directly quantify the amount of “new” methane generated and the effectiveness of MECoM stimulation approaches. Microorganisms, formation water, and coal obtained during a previous drilling project in the Powder River Basin, Birney, Montana were used to set up a series of benchtop stimulation experiments where we added incremental amounts of deuterated water to triplicate sets of stimulated microbes (methanogens). We hypothesized that as MECoM progresses, methanogens will incorporate the heavy water into new methane produced, as methanogens naturally uptake hydrogen during methanogenesis. The amount of hydrogen incorporated into methane from water is dependent on the methanogenic pathway (hydrogenotropic vs acetoclastic/methylotrophic). During the experiments, we saw a shift in the methanogenic pathway towards acetoclastic methanogenesis, which was indicated by a consistent shift in the enrichment of deuterium in the methane produced, methanogenic community, and a large kinetic fractionation. The enrichment of the methane as compared to the deuterium content of the water the microbes used followed a narrowly confined, predictable range of values. This predictable enrichment of the methane allows us to propose a quantification scheme for the amount of methane produced in larger field scale stimulations, as we can compare the change in the overall deuterium content of the in-situ methane with the known value before the stimulation. The success of our proof-of-concept laboratory experiments suggests that deuterium may be used as a tracer of “new” natural gas resources in field- to commercial-scale MECoM projects. In addition, additions of deuterated water may also be useful as a tracer in bioremediation projects where large background pools of contaminants or degradation products hamper traditional quantification techniques, microbial enhanced oil recovery, or other subsurface carbon cycling pathways.

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