Дисертації з теми "Natural gas/hydrogen mixtures"
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Mumby, Christopher. "Predictions of explosions and fires of natural gas/hydrogen mixtures for hazard assessment." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6354.
Повний текст джерелаVan, Norden Vincent Ray. "Reducing emissions of a large bore two stroke cycle engine using a natural gas and hydrogen mixture." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/736.
Повний текст джерелаDam, Bidhan Kumar. "Flashback propensity of gas mixtures." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
Повний текст джерелаMonteparo, Christopher Nicholas. "Gallium nitride sensors for hydrogen/nitrogen and hydrogen/carbon monoxide gas mixtures." [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0002838.
Повний текст джерелаSublette, Kerry Lyn. "Microbial desulfurization of natural gas /." Access abstract and link to full text, 1985. http://0-wwwlib.umi.com.library.utulsa.edu/dissertations/fullcit/8510388.
Повний текст джерелаGibrael, Nemir, and Hamse Hassan. "HYDROGEN-FIRED GAS TURBINE FOR POWER GENERATION WITH EXHAUST GAS RECIRCULATION : Emission and economic evaluation of pure hydrogen compare to natural gas." Thesis, Mälardalens högskola, Framtidens energi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-42306.
Повний текст джерелаWeiler, Justin D. "Numerical Simulation of Flame-Vortex Interactions in Natural and Synthetic Gas Mixtures." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4774.
Повний текст джерелаHolton, Maclain Marshall. "Autoignition delay time measurements for natural gas fuel components and their mixtures." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8976.
Повний текст джерелаThesis research directed by: Dept. of Mechanical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
Zhou, Jingjun. "Automatic isochoric apparatus for PVT and phase equilibrium studies of natural gas mixtures." [College Station, Tex. : Texas A&M University, 2005. http://hdl.handle.net/1969.1/ETD-TAMU-1004.
Повний текст джерелаWidia. "Variation of density with composition for natural gas mixtures in the supercritical region." Texas A&M University, 2003. http://hdl.handle.net/1969.1/1094.
Повний текст джерелаMcGlocklin, Kristin Hew Eden Mario R. "Economic analysis of various reforming techniques and fuel sources for hydrogen production." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Fall/Theses/MCGLOCKLIN_KRISTIN_35.pdf.
Повний текст джерелаPatil, Prashant Vithal. "Commissioning of a magnetic suspension densitometer for high-accuracy density measurements of natural gas mixtures." [College Station, Tex. : Texas A&M University, 2005. http://hdl.handle.net/1969.1/ETD-TAMU-1003.
Повний текст джерелаEjaz, Saquib. "High-accuracy P-p-T measurements of pure gas and natural gas like mixtures using a compact magnetic suspension densimeter." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5866.
Повний текст джерелаMoodley, Shawn. "Gas separation of steam and hydrogen mixtures using an α-alumina-Alumina supported NaA membrane / by S. Moodley". Thesis, North-West University, 2007. http://hdl.handle.net/10394/1890.
Повний текст джерелаCakal, Ulgen. "Natural Gas Purification By Zeolite Filled Polyethersulfone Based Mixed Matrix Membranes." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12611206/index.pdf.
Повний текст джерелаC, with a feed pressure of 3 bar. Moreover, the membranes were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermal gravimetric analyzer (TGA). The separation selectivities of all types of membranes generally observed to be independent of feed composition. The composition independency of these membranes eliminates the need of investigating at which feed gas composition the prepared membranes are best performing for practical applications. PES/SAPO-34/HMA MMMs with HMA loading of 10% and SAPO-34 loading of 20% demonstrated the highest separation selectivity of about 40, and the ideal selectivity of 44, among the used membranes.
Tarun, Cynthia. "Techno-Economic Study of CO2 Capture from Natural Gas Based Hydrogen Plants." Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/2837.
Повний текст джерелаIn the current H2 plants, CO2 emissions originate from two sources, the combustion flue gases from the steam reformer furnace and the off-gas from the process (steam reforming and water-gas shift) reactions. The objective of this study is to develop a process that captures CO2 at minimum energy penalty in typical H2 plants.
The approach is to look at the best operating conditions when considering the H2 and steam production, CO2 production and external fuel requirements. The simulation in this study incorporates the kinetics of the steam methane reforming (SMR) and the water gas shift (WGS) reactions. It also includes the integration of CO2 capture technologies to typical H2 plants using pressure swing adsorption (PSA) to purify the H2 product. These typical H2 plants are the world standard of producing H2 and are then considered as the base case for this study. The base case is modified to account for the implementation of CO2 capture technologies. Two capture schemes are tested in this study. The first process scheme is the integration of a monoethanolamine (MEA) CO2 scrubbing process. The other scheme is the introduction of a cardo polyimide hollow fibre membrane capture process. Both schemes are designed to capture 80% of the CO2 from the H2 process at a purity of 98%.
The simulation results show that the H2 plant with the integration of CO2 capture has to be operated at the lowest steam to carbon (S/C) ratio, highest inlet temperature of the SMR and lowest inlet temperatures for the WGS converters to attain lowest energy penalty. H2 plant with membrane separation technology requires higher electricity requirement. However, it produces better quality of steam than the H2 plant with MEA-CO2 capture process which is used to supply the electricity requirement of the process. Fuel (highvale coal) is burned to supply the additional electricity requirement. The membrane based H2 plant requires higher additional electricity requirement for most of the operating conditions tested. However, it requires comparable energy penalty than the H2 plant with MEA-CO2 capture process when operated at the lowest energy operating conditions at 80% CO2 recovery.
This thesis also investigates the sensitivity of the energy penalty as function of the percent CO2 recovery. The break-even point is determined at a certain amount of CO2 recovery where the amount of energy produced is equal to the amount of energy required. This point, where no additional energy is required, is approximately 73% CO2 recovery for the MEA based capture plant and 57% CO2 recovery for the membrane based capture plant.
The amount of CO2 emissions at various CO2 recoveries using the best operating conditions is also presented. The results show that MEA plant has comparable CO2 emissions to that of the membrane plant at 80% CO2 recovery. MEA plant is more attractive than membrane plant at lower CO2 recoveries.
Oettel, Christian Verfasser], and Kai [Akademischer Betreuer] [Sundmacher. "Electrochemical high temperature membrane reactor for the processing of hydrogen-carbon monoxide gas mixtures / Christian Oettel. Betreuer: Kai Sundmacher." Magdeburg : Universitätsbibliothek, 2013. http://d-nb.info/1054420777/34.
Повний текст джерелаZea, Luis. "EXPERIMENTAL ANALYSIS OF THE HYDROGEN SULFIDE ABSORTION PHENOMENA IN BRINE/OIL MIXTURES AS A FUNCTION OF SYSTEM PRESSURE AND H2S." Master's thesis, University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3053.
Повний текст джерелаM.S.
Department of Mechanical, Materials and Aerospace Engineering
Engineering and Computer Science
Aerospace Engineering MSAE
Cardoso, Simão Pedro Pereira. "Synthesis and characterization of small pore membranes and their application to the separation of hydrogen containing mixtures." Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/21173.
Повний текст джерелаAmong various methods for the separation of hydrogen containing mixtures, membrane technology has received special attention due to its simplicity of operation, moderate energy consumption, cost effectiveness, it is environmentally friendly and can be easily coupled with other separation methods. In particular, inorganic membranes exhibit relevant advantages such as high thermal, chemical and mechanical stabilities, minor plasticization and better control of pore size distribution. They can be divided into five main families: metallic and ceramic proton conducting membranes (dense phases), and silica, zeolite and carbon molecular sieve membranes (porous materials). With more than 200 framework types, zeolites possess uniform molecular pore dimensions and unique properties for catalytic, ion exchange, adsorption and membrane applications. This thesis is essentially devoted to zeolite (titanosilicate) membranes for hydrogen and light gases separation. Titanosilicates offer important benefits over the remaining zeolites: they are usually synthesized without organic templates, can be prepared under moderate pH conditions, exhibit novel possibilities of isomorphous framework substitution, and generally offer strong alkalinity. The main objectives of this dissertation were: (i) synthesis and characterization of titanosilicate membranes. The materials structure and morphology were examined by X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS); the dynamic characterization of membranes was accomplished by permeation assays with pure gases; (ii) deep analysis of experimental results, with the objective to disclose the mass transport mechanisms that prevail in the membrane; (iii) accurate modeling of permeation data using theoretically sound approaches like the generalized Maxwell-Stefan (MS) formalism; (iv) development of new MS thermodynamic factors to represent the surface diffusion of pure and multicomponent gases through microporous membranes. Here, several important (though less studied) isotherms were tested, the influence of the solid loading upon surface diffusivity was deeply evaluated, and the predictive ability of the whole model was validated. The hydrothermal synthesis and characterization of AM-2 and AM-3 powder and supported membranes have been performed. Altogether, ca. thirty and more than one hundred syntheses of AM-2 and AM-3 powder, respectively, have been accomplished, and eight AM-2 and twenty AM-3 membranes have been prepared on tubular -alumina and stainless-steel supports by seeding and secondary growth. All powders were characterized by XRD and/or SEM, and three AM-2 and seven AM-3 membranes were dynamically tested. The permeation of pure gases at programmed temperature and fixed transmembrane pressure drop ( P) was carried out in order to evaluate the membranes quality and identify the governing transport mechanisms (e.g. viscous flow, Knudsen regime, surface diffusion, activated gaseous diffusion). Additionally, more than one hundred permeance measurements were conducted at various temperatures and pressures using different gases (H2, He, N2, O2 and CO2). The best AM-3 membrane was studied in detail at P=0.5, 1.0 and 1.5 bar, at fixed and programmed temperatures between 304 and 394 K, using H2, He, N2, O2 and CO2. The results provided selectivities towards hydrogen up to 3.5, and disclosed in all cases an activated behavior typical of surface diffusion, a small contribution of viscous flow due to macro-defects, and a minor contribution of Knudsen mechanism due to meso-defects. The gas permeation was accurately modeled using Maxwell-Stefan theory, achieving an average deviation of only 3.42 % for all molecules. The rigorous MS thermodynamic factors of various relevant isotherms – Toth, Dubinin-Astakhov (DA) and Dubinin-Radushkevich (DR) – were derived in this work for the first time, with the objective to model the permeation of pure and mixed gases through zeolite membranes. The DA and DR isotherms received special attention, taking into account they are often adopted to represent the adsorption equilibrium of most industrial adsorbents that possess a welldeveloped porous structure, especially of carbonaceous origin. The MS factors for DA and DR isotherms were validated using equilibrium and flux data for methane/silicalite-1, ethane/silicalite-1 and (methane,ethane)/ silicalite-1 systems according to the following procedure: (i) the unary isotherms were fitted to the corresponding data, while their binary expressions were predicted from the previous ones; (ii) the influence of surface loading upon methane and ethane diffusivities was carefully assessed; (iii) the MS diffusion parameters of each gas were obtained from unary permeation data; (iv) the MS counter-sorption diffusivities were then predicted using the Vignes correlation; (v) the separation of methane/ethane mixtures using the silicalite-1 membrane was totally predicted using the new MS thermodynamic factors combined with the binary isotherms. The results demonstrated the validity of this approach, particularly if DA isotherm is selected. Besides the main focus of this PhD on membranes, ion exchange experiments and modeling were also included. The removal of ionic contaminants (Cd2+ and Hg2+) from aqueous solutions was studied using synthesized stannosilicate AV- 6 and titanosilicate ETS-4. In the case of the Cd2+/K+/AV-6 system, the kinetic removal was modeled with Maxwell-Stefan (MS) and Nernst-Plank (NP) equations, while equilibrium was modeled with mass action law and activity coefficients in both solution (Debye-Hu ckel and Pitzer models) and exchanger (Wilson model) phases. The experimental data proved the ion exchange ability of AV-6 to sorb cadmium(II), and excellent results were achieved for the equilibrium isotherm (deviations around 6.6 %) and kinetic modeling (MS, 3.74 %; NP, 3.71 %). It was shown that the solid phase is clearly non-ideal. The investigation of the ternary system (Cd2+,Hg2+)/Na+/ETS-4 confirmed the large capacity of ETS-4 (5.44 meq g-1) and its selectivity towards both toxic metals, particularly Cd2+. However, the trends of the ion exchange kinetics were very distinct, because the internal diffusivity of cadmium(II) is higher than that of mercury(II). These results are in accordance with the effective ionic radius of both species, namely, 102 pm for Hg2+ and only 95 for Cd2+.
Entre diversos métodos de separação de misturas gasosas contendo hidrogénio, os processos membranares têm recebido uma atenção especial devido à sua simplicidade de operação, consumo moderado de energia, boa relação custo-eficiência, vantagens para o meio ambiente, e podem ser facilmente combinados com outros métodos de separação. Em particular, as membranas inorgânicas exibem vantagens relevantes, podendo citar-se as estabilidades térmica, química e mecânica elevadas, plasticização reduzida e um melhor controlo da distribuição do tamanho dos poros. Estas podem ser divididas em cinco famílias principais: metálicas e cerâmicas densas (membranas densas); e de sílica, zeolíticas e de peneiro molecular de carbono (membranas porosas). Com mais de 200 estruturas, os zeólitos possuem poros uniformes de dimensão molecular e propriedades únicas para aplicações catalíticas, de permuta iónica, de adsorção e membranares. Esta dissertação dedica-se fundamentalmente a membranas zeolíticas (titanossilicatos) para a separação de hidrogénio e gases leves. Os titanossilicatos oferecem vantagens importantes em relação aos restantes zeólitos: são geralmente sintetizados sem agentes orgânicos estruturantes e sob condições moderadas de pH, exibem novas possibilidades de substituição isomórfica da matriz, e oferecem geralmente uma forte alcalinidade. Os objetivos principais desta dissertação foram: (i) síntese e caracterização de membranas de titanossilicatos. A estrutura dos materiais e a sua morfologia foram examinadas por difração de raios-X (DRX) e microscopia eletrónica de varrimento acoplada a espectroscopia de energia dispersiva de raios-X (SEM/EDS). A caracterização dinâmica das membranas foi efetuada com ensaios de permeação utilizando gases puros; (ii) análise aprofundada dos resultados experimentais, com o objetivo de compreender os mecanismos de transporte de massa que prevalecem na membrana; (iii) modelação rigorosa dos dados de permeação, seguindo abordagens como o formalismo de Maxwell-Stefan (MS); (iv) derivação de novos fatores termodinâmicos de MS para representar a difusão superficial de gases puros e misturas através de membranas microporosas. Foram investigadas isotérmicas importantes, (mesmo que pouco utilizadas na literatura), a dependência da difusividade superficial com a concentração no sólido, e a capacidade preditiva de todo o modelo. A síntese hidrotérmica e a caracterização dos titanossilicatos AM-2 e AM-3 foram efetuadas com o material na forma de pó e suportado em membranas. Realizaram-se cerca de trinta sínteses de cristais de AM-2 e mais de uma centena de AM-3, para além de oito membranas de AM-2 e vinte membranas de AM-3 suportadas em tubos de -alumina e de aço inoxidável, recorrendo ao método do crescimento secundário. Todos os cristais obtidos foram caracterizados por DRX e/ou S SEM, e testaram-se dinamicamente três SEM membranas de AM-2 e sete membranas de AM-3. A permeação de gases puros a temperatura programada e a pressão transmembranar fixa ( P) foi realizada com o objetivo de avaliar a qualidade das membranas e identificar os mecanismos de transporte envolvidos (fluxo viscoso, regime de Knudsen, difusão superficial, difusão gasosa ativada). Foram concluídas mais de uma centena de medições de permeação a várias temperaturas e pressões usando gases diferentes (H2, He, N2, O2 e CO2). A melhor membrana de AM-3 foi estudada em detalhe para P = 0,5, 1,0 e 1,5 bar, a temperatura fixa e a temperatura programada entre 304 e 394 K, usando H2, He, N2, O2 e CO2. Os resultados obtidos evidenciaram seletividades para o hidrogénio até 3,5, comportamento ativado típico de difusão superficial em todos os casos, uma pequena contribuição de fluxo viscoso devido a macrodefeitos e uma contribuição residual do mecanismo de Knudsen atribuível a meso-defeitos. A permeação gasosa foi modelada rigorosamente usando o formalismo de Maxwell-Stefan, apresentando um desvio médio de apenas 3,42% para todas as moléculas simultaneamente. Os fatores termodinâmicos de MS para as isotérmicas de Toth, Dubinin- Astakhov (DA) e Dubinin-Radushkevich (DR) foram derivados neste trabalho, com o objetivo de modelar a permeação de gases puros e misturas através de membranas zeolíticas. As isotérmicas de DA e DR receberam uma atenção especial, tendo em conta que são frequentemente adotadas para representar o equilíbrio de adsorção da maioria dos adsorventes industriais que têm uma estrutura porosa bem definida, especialmente com origem carbonácea. Os fatores de Maxwell-Stefan para DA e DR foram validados com dados experimentais de equilíbrio e de fluxo dos sistemas metano/silicalite-1, etano/silicalite-1 e (metano,etano)/silicalite-1 de acordo com o seguinte procedimento: (i) os parâmetros das isotérmicas dos gases puros foram ajustados aos dados correspondentes, e as isotérmicas binárias foram previstas a partir das anteriores; (ii) a influência da concentração do sólido sobre as difusividades superficiais do metano e do etano foi analisada cuidadosamente; (iii) os parâmetros de difusão de MS de cada gás foram obtidos a partir dos dados de permeação mono-componente; (iv) os coeficientes de difusão multicomponente de MS foram estimados com a correlação de Vignes; (v) a separação de misturas metano/etano usando uma membrana de silicalite-1 foi totalmente prevista com recurso aos novos fatores termodinâmicos de MS combinados com as isotérmicas binárias. Os resultados comprovaram a validade desta abordagem, especialmente no caso da isotérmica de DA. Apesar de a área principal deste doutoramento estar relacionada com membranas, foram incluídas experiências de permuta iónica e sua modelação. A remoção de contaminantes tóxicos (Cd2+ e Hg2+) de soluções aquosas foi estudada usando o estanhossilicato AV-6 e o titanossilicato ETS-4. No caso do sistema Cd2+/K+/AV-6, a cinética de remoção foi modelada com as equações de Maxwell-Stefan (MS) e de Nernst-Plank (NP), enquanto o equilíbrio foi modelado com a lei da ação das massas expressa em atividades, usando-se coeficientes de atividade na solução (modelos de Debye-Hückel e Pitzer) e no permutador (modelo de Wilson). Os dados experimentais evidenciaram a capacidade de permuta do AV-6 para sorver cádmio(II) e obtiveram-se resultados excelentes para a isotérmica de equilíbrio (desvios de 6,6 %) e para a modelação cinética (MS = 3,74 %; NP = 3,71%). Ficou ainda demonstrado que a fase sólida é claramente não-ideal. A investigação do sistema ternário (Cd2+,Hg2+)/Na+/ETS-4 confirmou a elevada capacidade do ETS-4 (5,44 meq g-1) e a sua seletividade para os dois metais tóxicos, particularmente para o Cd2+. Contudo, o comportamento das cinéticas de permuta iónica foi muito distinto, uma vez que a difusividade interna do cádmio(II) é superior à do mercúrio(II). Estes resultados estão de acordo com o raio iónico efetivo de ambas as espécies, ou seja, 102 pm para o Hg2+ e apenas 95 pm para o Cd2+.
Appressi, Lorenzo. "Biogas and bio-hydrogen: production and uses. A review." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9071/.
Повний текст джерелаKunz, Oliver. "A new equation of state for natural gases and other mixtures for the gas and liquid regions and the phase equilibrium." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=983888655.
Повний текст джерелаAtilhan, Mert. "High accuracy p-rho-t measurements up to 200 MPa between 200 K and 500 K using a compact single sinker magnetic suspension densimeter for pure and natural gas like mixtures." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1903.
Повний текст джерелаFelder, Remo. "Well-to-wheel analysis of renewable transport fuels : synthetic natural gas from wood gasification and hydrogen from concentrated solar energy." lizenzfrei, 2007. http://e-collection.ethbib.ethz.ch/view/eth:30096.
Повний текст джерелаShasby, Benjamin Matthew. "Alternative Fuels: Incompletely Addressing the Problems of the Automobile." Virginia Tech, 2004. http://hdl.handle.net/10919/9976.
Повний текст джерелаMaster of Urban and Regional Planning
Ally, Jamie. "Life cycle assessment and life cycle costing of hydrogen fuel cell, natural gas, and diesel bus transportation systems in Western Australia." Thesis, Ally, Jamie (2015) Life cycle assessment and life cycle costing of hydrogen fuel cell, natural gas, and diesel bus transportation systems in Western Australia. PhD thesis, Murdoch University, 2015. https://researchrepository.murdoch.edu.au/id/eprint/32053/.
Повний текст джерелаLobkov, Dmitri Dmitrievich. "Analise economica para a substituição do uso de combustivel diesel por GNC no transporte publico de passageiros." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258235.
Повний текст джерелаDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
Made available in DSpace on 2018-08-06T01:41:02Z (GMT). No. of bitstreams: 1 Lobkov_DmitriDmitrievich_M.pdf: 951415 bytes, checksum: 540ad2a18af759bf3bb0d0715b212f7f (MD5) Previous issue date: 2005
Resumo: Neste trabalho se apresentam argumentos econômicos e de meio ambiente para o uso de GNC em ônibus de transporte público, na forma de gás-diesel. Assim, os objetivos deste trabalho são: Analisar e comparar a experiência real do uso de gás-diesel em outros países e também no Brasil, para oferecer alternativa de combustível Gás Natural Comprimido (GNC) para as empresas de transporte urbano. Fundamentar as vantagens econômicas de reduzir o consumo de combustível diesel em ônibus a gás-diesel, usando como combustível uma mistura de diesel e GNC. Fazer os cálculos de demanda crescente de GNC com a substituição de combustível diesel por GNC nos ônibus urbanos
Abstract: This work presents strong economical and enviromental arguments in favour of the use of CNG (Compress Natural Gas) in the passengers's public transport (buses). The main object of this work is to analyse and compare the real experience in the use of gas/diesel fuel in Brazil and in other countries in an attempt to give an alternative gas fuel system in the public transport. Also it establishes and explains the economical advantage in reducing the consume of diesel fuel in the gas/diesel buses, by the use of a diesel/CNG mixture. Finally, the calculations made show the increasing demand of CNG with the substitution of diesel fuel by CNG in the buses of the public transport
Mestrado
Geotecnia
Mestre em Engenharia Civil
Achoundong, Carine Saha Kuete. "Engineering economical membrane materials for aggressive sour gas separations." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50289.
Повний текст джерелаVASUDEVAN, ROHAN ADITHYA. "SWOT-PESTEL Study of Constraints to Decarbonization of the Natural Gas System in the EU Techno-economic analysis of hydrogen production in Portugal : Techno-economic analysis of hydrogen production in Portugal." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-292186.
Повний текст джерелаDet starka behovet av att ta itu med klimatförändringarna och deras negativa effekter är omfattande världen över. Den europeiska unionen utgör en pionjär när det gäller att såväl hantera sina koldioxidberoende och utsläpp som att implementera reglerande miljöpolitik, och framstår därmed som överlägsen andra stater och organisationer i detta hänseende. Unionen är emellertid fortfarande mycket beroende av fossilt bränsle för att uppfylla sina energibehov, och kvarstår därför som en av världens största importörer av naturgas. Syftet med denna forskningsavhandling är att undersöka befintliga hinder och restriktioner i EU: s politiska ramverk som medför konsekvenser avkolningen av naturgas, samt att undersöka de utjämnande kostnaderna för väteproduktion (LCOH) som kan användas för att avkolna naturgassektorn. Därmed utförs en omfattande studie baserad på befintlig akademisk och vetenskaplig litteratur, EU: s politiska ramverk och stadgar som är relevanta för naturgasindustrin. Dessutom genomförs en teknisk-ekonomisk analys av eventuella ersättningar av naturgas med väte. Valet av väte som forskningsobjekt motiveras olika forskningsstudier som indikerar vikten och förmågan att ersätta till naturgas. Till sist berör studien Portugal. som tillhandahåller en lämplig miljö för billig och grön vätgasproduktion. Av denna anledning är Portugal utvalt som den viktigaste utvärderingsregionen. Studien utvärderar det nuvarande ramverket baserat på en SWOT-analys ((Strength, Weakness, and Opportunities & Weakness), som inkluderar en PESTEL (Political, Economical, Social, Technological, Environmental och Legal) makroekonomisk faktoranalys och elicitering. Den utjömnade vätekostnaden beräknades i blått (SMR - Ångmetanreformering med naturgas som råvara) och grönt väte (elektrolyser med el från elnät, sol och vindkällor). Kostnaderna var specifika för de portugisiska förhållandena under åren 2020, 2030 och 2050 baserat på tillgänglighet av data samt anpassningen till den nationella energi- och klimatplanen (NECP) och klimatåtgärdsramen 2050. Storleken på elektrolyserar baseras på den nuvarande marknadskapaciteten medan SMR är begränsad till 300 MW. Avhandlingen tar endast hänsyn till produktionen av vätgas. Transmission, distribution och lagring av väte ligger utanför analysens räckvidd. Resultaten visar att hindren är främst relaterade till kostnadskonkurrens, förändringar i stadgar och bestämmelser, incitament och begränsningar i formerandet av efterfrågan på koldioxidsnåla gaser på marknaden. Att säkerställa energiförsörjning och tillgång på ett ekonomiskt hållbart sätt kräver omedelbara ändringar av reglerna och politiken, såsom att stimulera utbudet, att skapa en efterfrågan på koldioxidsnåla gaser och genom att beskatta kol. När det gäller LCOH dominerar blåväte beträffande produktionskostnaderna (1,33 € per kg H2) jämfört med grönt väte (4,27 respektive 3,68 € per kg H2) från elnät respektive solenergi. Osäkerhetsanalysen visar vikten av investeringskostnader och effektiviteten vid elektrolysörer och koldioxidskatten för SMR. Med förbättringar av elektrolys-tekniken och ökad koldioxidskatt skulle upptagningen av grön vätgas vara enklare och säkerställa en rättvis men konkurrenskraftig gasmarknad.
Lomax, Franklin D. "Investigation of steam reformation of natural gas for the very small scale production of hydrogen fuel for light duty vehicles in appliance-type refueling systems." Master's thesis, This resource online, 1997. http://scholar.lib.vt.edu/theses/available/etd-09052009-040323/.
Повний текст джерелаOzgul, Ercin. "Geochemical assessment of gaseous hydrocarbons mixing of bacterial and thermogenic methane in the deep subsurface petroleum system, Gulf of Mexico continental slope /." Texas A&M University, 2002. http://hdl.handle.net/1969/223.
Повний текст джерелаGerosa, Tatiana Magalhães. "\"O estudo da utilização do gás natural como insumo para a indústria química e petroquímica: modelagem de uma planta gás-química\"." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/86/86131/tde-18072007-155710/.
Повний текст джерелаThis work has as objective to present, through the modeling of a gas-chemical plant and also, through the identification of the current available technologies, the versatility of the use of natural gas as a raw material for the chemical industry, aiming the production of methanol, ammonia and hydrogen, from the fraction methane, as well as in the petrochemical industry, the attainment of ethene from the ethane fraction. Based in a market research, it was determined that amongst the products to be obtained from methane, methanol is the product that presents the most critical internal scenario. This situation is reflected through the continuous increase of the importation; without it there is no signaling that this deficit can be overcome, unless new industrials units are constructed. On the other hand, the ammonia scenario is steady and, despite presenting a deficit in the national production, the current situation does not reveal to very so critical, carried through the projection of the demand up to 2030. Analyzing the petrochemical scene, in a few years the ethene production will reach its pass and the biggest diagnosed impediment is related to the availability of the feedstock. Considering the technique proposal, the modeling of the gas-chemical plant shows the viability of concentrating the production of ammonia, methanol and hydrogen in the same site and that, for these products, the current technologies are mature and very well developed. Already the ethene production, from ethane, does not have to be directly entailed, in principle, to the attainment of the other products, considering the high volume of natural gas necessary to liberate the necessary amount of ethane for the sustainable of the project.
Pinto, Cristiano da Silva 1973. "Introdução de misturas de GNV e hidrogênio (Hidrano) em veículos convencionais no Brasil e seus impactos econômicos, ambientais e energéticos." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263900.
Повний текст джерелаTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: Diversas estratégias têm sido propostas para a introdução do hidrogênio na economia, especificamente no setor de transportes para se reduzir impactos ambientais em comparação com os combustíveis convencionais. Uma das estratégias implica na utilização de Hidrano (misturas de hidrogênio e Gás Natural Veicular), fazendo uso da infraestrutura de postos de GNV e dos veículos já existentes convertidos para uso de GNV. Dessa forma custos e prazos são reduzidos, tornando a introdução do hidrogênio mais promissora economicamente. Esta tese verifica se o hidrogênio pode ser imediatamente introduzido no mercado energético brasileiro através do Hidrano, com frações molares de hidrogênio de 10%, 20% e 30%. O hidrogênio será gerado através da eletrólise da água nos postos de GNV. Foram então determinados os custos do hidrogênio, os preços e a competitividade do Hidrano de forma a atender o perfil de vendas de um posto de porte médio nos Estados de São Paulo e Rio de Janeiro. O preço do Hidrano ao consumidor depende principalmente do preço de seu maior constituinte, o GNV, vendido na época a 1,308 R$/m3 no Estado de São Paulo e a 1,662 R$/m3 no Estado do Rio de Janeiro. O preço do Hidrano ao consumidor varia entre 1,474 R$/m3 e 2,047 R$/m3, dependendo de sua composição e da região. Em vista de sua competitividade em relação aos outros combustíveis automotivos, o Hidrano 10 apresenta bom potencial de introdução no mercado, inclusive do ponto de vista econômico. A competitividade entre os combustíveis no Estado de São Paulo é de 0,280 R$/km para a gasolina, 0,259 R$/km para o etanol, 0,111 R$/km para o GNV, 0,129 R$/km para o Hidrano 10 com tarifação do Grupo B3 e 0,125 R$/km para o Hidrano 10 com tarifação do Grupo A4 Convencional. No Estado do Rio de Janeiro a competitividade é de 0,300 R$/km para a gasolina, 0,311 R$/km para o etanol, 0,141 R$/km para o GNV, 0,161 R$/km para o Hidrano 10 com tarifação do Grupo B3 e 0,157 R$/km para o Hidrano 10 com tarifação do A4 Convencional. Também foram estimados os impactos dessa proposta em termos energéticos e ambientais. Há redução de emissões de CO2 e CO. As emissões de THC serão possivelmente reduzidas e as de NOx aumentadas. A proposta do Hidrano permite às concessionárias de energia elétrica entrarem no mercado de combustíveis veiculares e aumentar suas vendas. Ao mesmo tempo as concessionárias de gás natural terão reduzidas as vendas de GNV no curto prazo, o que deverá ser revertido no médio e longo prazos com os ganhos de rendimento trazidos pelo Hidrano aos veículos
Abstract: Several strategies have been proposed to introduce hydrogen in the economy specifically in the transport sector in order to reduce environmental impacts of conventional fuels. One of the strategies implies in adding hydrogen to compressed natural gas (HCNG), making use of the existing refueling stations and natural gas fleet. Thus the costs and time for the introduction of hydrogen in the economy will be reduced. This thesis verifies whether hydrogen can be immediately introduced into the Brazilian energy market by means of HCNG, containing mole fractions of 10%, 20% and 30% of hydrogen, employed as fuel for conventional vehicles adapted to CNG. Hydrogen will be generated by water electrolysis in the CNG station. Then the cost of hydrogen and the prices and competitiveness of HCNG were determined to meet the sales profile of a midsize gas station in the states of Sao Paulo and Rio de Janeiro. The final price of HCNG depends mainly on the price of its major constituent, CNG, sold at that time for 1,308 R$/m3 in the State of São Paulo and for 1,662 R$/m3 in the State of Rio de Janeiro. The price of HCNG to the consumer varies between 1,474 R$/m3 e 2,047 R$/m3, depending on its composition and the region. In view of its competitiveness compared to other automotive fuels, HCNG 10 (CNG with 10% molar fraction of hydrogen) shows good potential for marketing. The competitiveness among fuels in the State of Sao Paulo is 0,280 R$/km for gasoline, 0,259 R$/km for ethanol, 0,111 R$/km for CNG, 0,129 R$/km for HCNG 10 with power tariff B3 and 0,125 R$/km for HCNG 10 with power tariff A4 Conventional. In the State of Rio de Janeiro the competitiveness is 0,300 R$/km for gasoline, 0,311 R$/km for ethanol, 0,141 R$/km for CNG, 0,161 R$/km for HCNG 10 with power tariff B3 and 0,157 R$/km for HCNG 10 with power tariff A4 Conventional. The energy and environmental impacts of this proposal were also estimated. There is a reduction of CO2 and CO emissions. THC emissions are likely to be reduced and NOx are likely to increase. The proposal of introducing HCNG allows electric utilities to enter the market for vehicular fuels and increase their sales. At the same time, natural gas utilities will have the sales of CNG reduced in the short term, although this trend may be reversed in the medium and long terms with performance gains brought by HCNG to vehicles
Doutorado
Planejamento de Sistemas Energeticos
Doutor em Planejamento de Sistemas Energéticos
Machado, Taís Espíndola. "Decomposição catalítica do metano sobre catalisador Cu-Ni-Al : taxa da reação e regeneração do catalisador." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/10051.
Повний текст джерелаHydrogen is considered the ideal source of energy, because its combustion doesn't generate pollutants, just water. The catalytic decomposition of methane stands out among the available processes for hydrogen production because, unlike steam reform and partial oxidation, in this route there is not production of CO. The objective of this work is the kinetic study and the reaction rate determination of methane catalytic decomposition over Cu-Ni-Al catalyst for pure hydrogen production. In order to determinate the limiting step, reaction was conducted using four catalyst particle size ranges and the Mears criterion was applied. The external diffusion effects and diffusion in porous catalysts step do not influence significantly the reaction rate in the studied conditions. The reaction was carried out in a thermobalance with different temperatures (500 to 600°C) and methane concentrations (0.5 to 1.2 mol m-3) to determining the reaction rate. It was observed that the reaction is of first order, with activation energy of 50655 J mol-1. The reaction also forms carbon, which is deposited on the catalyst surface causing deactivation. The carbon oxidation for catalyst regeneration was also investigated. Repeated reaction-regeneration cycles were carried out, being the regeneration composed by oxidation or by oxidation and reduction. The oxidation was carried out at different temperatures (500 to 600°C) and times (20 to 75min), with the reaction happening in severe conditions (600°C and methane concentration of 1.2 mol m-3). The best regeneration condition, that is, the condition that allows a larger number of cycles with low activity loss, it was determined. It was also observed that the deposited carbon is in the nanotubes form, which has exceptional properties. The structure of carbon nanotubes formed during the reaction was analyzed by Scanning Electron Microscopy (SEM).
Balogun, Nurudeen. "The Microstructure, Tensile Deformation, Cyclic Fatigue and Final Fracture Behavior of Alloy Steel 4140 for use in CNG (Compressed Natural Gas) and Hydrogen Pressure Vessels." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1290227797.
Повний текст джерелаMartins, André Rosa. "Desenvolvimento de catalisadores de platina suportada em óxido de alumínio e magnésio para reforma a vapor do gás natural." Instituto de Química, 2010. http://repositorio.ufba.br/ri/handle/ri/20214.
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CNPQ
A reforma a vapor de metano é a principal via de produção de hidrogênio e de gás de síntese. Industrialmente, esta reação ocorre sobre um catalisador de níquel suportado em alumina que, embora apresente alta atividade e seletividade, além de baixo custo, tem a desvantagem de apresentar uma curta vida útil, devido à deposição de coque. Por outro lado, os metais nobres apresentam mais alta atividade catalítica e mais resistência à deposição de coque e à sinterização do que o catalisador comercial. Além disso, a adição de magnésio à alumina é uma boa opção para evitar a deposição de coque e, também, aumentar a resistência térmica do sólido. Considerando essas vantagens estudou-se, neste trabalho, o efeito da adição de magnésio sobre as propriedades de um catalisador de platina suportada em alumina, a fim de desenvolver novos e eficientes catalisadores para produzir hidrogênio, a partir da reforma a vapor do metano. As amostras com razões molares Al/Mg=0,2, 2 e 5 foram preparadas pelo método de precipitação e impregnadas com 1 % (m/m) de platina. Os sólidos foram caracterizados por análise química, termogravimetria, análise térmica diferencial, espectroscopia de infravermelho com transformadas de Fourier, difração de raios X, redução à temperatura programada, medida da área superficial específica e de porosidade, espectroscopia de infravermelho com transformadas de Fourier usando monóxido de carbono como molécula sonda, dessorção à temperatura programada de amônia adsorvida, espectroscopia fotoeletrônica de raios X e medida do teor de carbono. Os catalisadores foram avaliados a 600 oC e 1 atm, sob uma razão vapor/metano = 4. Os catalisadores mais ricos em alumínio (sem magnésio e com Al/Mg= 5) mostraram a estrutura da γ-alumina, enquanto os demais mostraram a estrutura da periclase. A presença de magnésio diminuiu a área superficial específica da alumina devido à mudança de estrutura. A interação entre a platina e o suporte também aumentou com a quantidade de magnésio, que também alterou a natureza e a quantidade dos sítios ácidos nos sólidos. De modo geral, o magnésio aumentou a quantidade de platina na superfície dos catalisadores e a quantidade de átomos de platina ricos em elétrons, como conseqüência do aumento de sua interação com o suporte. Todos os catalisadores foram ativos na reforma a vapor do metano e seletivos ao hidrogênio. Numa tendência geral, o magnésio favoreceu a atividade e seletividade dos catalisadores. A amostra com Mg/Al= 5 foi o catalisador mais ativo e seletivo, o que pode ser relacionado à sua área superficial específica mais alta, assim como ao teor mais elevado de átomos de platina mais ricos em elétrons na superfície.
Methane steam reforming is the main route to produce hydrogen and synthesis gas. Industrially, this reaction occurs on an alumina-supported nickel catalyst which, although shows high activity and selectivity, besides low price, it has the disadvantage of showing short life because of coke deposition. On the other hand, noble metals show high activity and are more resistant against coke deposition and sintering than the commercial catalyst. Besides, the addition of magnesium to alumina seems to be a good option to prevent coke deposition and also to increase the thermal resistance. Considering these advantages, the effect of magnesium addition on the properties of alumina-supported platinum was studied in this work, aiming to develop new efficient catalysts to produce hydrogen by methane steam reforming. Samples with Al/Mg (molar) = 0.2, 2 and 5 were prepared by precipitation method and impregnated with 1% (w/w) platinum. The solids were characterized by chemical analysis, thermogravimetry, differential thermal analysis, Fourier transform infrared spectroscopy, X-ray diffraction, temperature programmed reduction, specific surface area and porosity measurement, Fourier transform infrared spectroscopy using carbon monoxide as probe molecule, temperature programmed desorption of ammonia, X-ray photoelectron spectroscopy and carbon content measurement. The catalysts were evaluated at 600 oC and 1 atm, under a steam to methane molar ratio of 4. The catalysts richer in alumina (magnesium-free and with Al/Mg= 5 and 2) showed the γ-alumina structure while the others showed the periclase structure. The presence of magnesium increased the specific surface area of alumina because of the change in the structure. The interaction between platinum and the support also increased with the amount of magnesium which also changed the kind and the amount of acidic sites. As a whole magnesium also increased the amount of platinum on the catalyst surface and of electron-rich platinum atoms, as a consequence of the increase of its interaction with the support. All catalysts were active in methane steam reforming and selective to hydrogen. In a general tendency, magnesium favored the activity and selective of the catalysts. The sample with Al/Mg= 5 was the most active and selective catalyst, a fact that was related to its highest specific surface area as well as to the highest amount of electron-richest platinum atoms on the surface.
Setlock, Robert J. Jr. "Hydrostatic Pressure Retainment." Ohio University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1091108803.
Повний текст джерелаMaleki, Rahil. "Consequences Analysis of CH4/H2S Release in Offshore Platform." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
Знайти повний текст джерелаLopes, Daniel Gabriel. "Determinação dos parâmetros térmicos de um sistema de purificação de hidrogênio para aplicação em células a combustível." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263919.
Повний текст джерелаDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: Ao avaliar a evolução do uso da energia pelo homem, percebe-se uma tendência à utilização de combustíveis com menos carbono e mais hidrogênio. Atualmente, observa-se um empenho pela utilização de combustíveis gasosos, como o gás natural, que possui uma relação de 4 átomos de hidrogênio para 1 átomo de carbono. Esta evolução permite estimar a utilização do hidrogênio gasoso para o futuro. Por se tratar de um vetor energético e não de uma fonte de energia, o hidrogênio precisa ser extraído de algum composto para ser utilizado. Examinando-se a literatura pertinente dos últimos anos, verifica-se que há em todo o mundo um grande esforço e uma grande expectativa quanto ao uso energético do hidrogênio em células a combustível, já que a eficiência destes equipamentos é superior à eficiência dos dispositivos tradicionais que utilizam à combustão. Sua aplicação se dá em diversos sistemas energéticos, estacionários ou móveis. Devido á exigência de elevada pureza para o hidrogênio utilizado em células a combustível do tipo PEM, a produção de hidrogênio a partir do processo de reforma de gás natural e o sistema de purificação deste hidrogênio tem sido estudado pelos principais centros de pesquisa nacionais. Por se tratar de umas das formas mais baratas para obtenção de hidrogênio para aplicação em células a combustível, o conhecimento desta tecnologia poderá conduzir à competitividade do uso energético do hidrogênio com um menor custo num menor prazo, o que a torna uma tecnologia estratégica. O objetivo geral desta dissertação é apresentar os principais processos de purificação do gás de síntese proveniente da reforma do gás natural para o fornecimento de hidrogênio com pureza suficiente para uso em células a combustível do tipo PEM e apresentar as considerações teóricas e experimentais sobre o funcionamento do sistema de purificação construído pelo Laboratório de Hidrogênio da Unicamp para desenvolvimento desta dissertação
Abstract: Evaluating the evolution of energy use by humanity it is observed a tendency to use fuels with lower carbon content and more hydrogen. Currently, there is a commitment to use fuels such as natural gas that has a ratio of 4 hydrogen atoms to 1 carbon atom. That evolution allows the estimation of gaseous hydrogen use for the future. Hydrogen is an energy vector, not an energy source, and then it must be extracted from a compound to feed fuel cells. The literature of recent years shows that there is a great effort and a huge expectation for the use of fuel cells which achieve higher efficiencies than traditional combustion devices. Fuel cells can be used in stationary, automotive or portable energy systems and its manufacturing technology has left laboratories and research centers is now being developed by companies with large investments. Since PEM fuel cells require high purity hydrogen, the hydrogen production from natural gas reforming process and the hydrogen purification systems have been studied by Brazilian research centers. Because this process is one of the cheapest methods to obtain hydrogen for use in fuel cells, the knowledge of this technology could lead to the competitive use of hydrogen energy at a lower cost in a shorter term, making it a strategic technology. The general objective of this dissertation is to present the main processes for the purification of synthesis gas from the reforming of natural gas to supply hydrogen with sufficient purity for its use in PEM fuel cells and present the theoretical and experimental considerations about the purification system built by the Hydrogen Laboratory at Unicamp for the development of this dissertation
Mestrado
Termica e Fluidos
Mestre em Engenharia Mecânica
Barbosa, Mayara Ferreira. "Um método automático de preparação de misturas gasosas para determinação cromatográfica de metano, etano e propano em GNV." Universidade Federal da Paraíba, 2015. http://tede.biblioteca.ufpb.br:8080/handle/tede/8214.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The compressed natural gas (CNG) is a fossil derivative mostly comprised of light hydrocarbons (methane, ethane, and propane), which has great energy importance for modern society. Considering the growing demand for CNG, it is also necessary to an effective control of the composition of the majority gases, which are mainly responsible for the energy efficiency of this fuel. The composition of these gases in CNG follows a certain pattern of conformity (control group) established by the ANP (National Agency of Petroleum, Natural Gas and Biofuels), to ensure the energy efficiency of CNG sold in Brazil. This work proposes the development of a methodology for automatic preparation of gas mixtures of methane standards, ethane and propane, in order to chromatographic determination of these gases levels in CNG, employing elaborate calibration models and validated by analysis of variance (ANOVA) and test recovery. The automatic system is of the dynamic type and is fully controlled by a program in order to prepare, as programmed by the user, binary mixtures of nitrogen / methane / nitrogen and nitrogen ethane / propane at levels (at fraction mol / mol) ranging in order to obtain good calibration models that consider the concentrations of these gases in the CNG. The evaluation methodology using ANOVA was quite satisfactory, the models built for the three gases methane, ethane and propane showed a high correlation (R2> 0.99) and significant in the regression, and showed no lack of fit and systematic variation at the residual plot. The performance parameters obtained from built models had lower detection and quantification limits 10-2 to 10-1, the analytical frequency was 4 samples per hour. A recovery study , involving three gas mixtures of certified composition and Natural Gas sample Vehicle (NGV) was also performed and the percentage values mean were 99.7 ± 3.1; 100.7 ± 4.4 and 98.0 ± 5.8 for methane, ethane and propane, respectively. The conclusion is based on the recovery values, as well as ANOVA, the proposed method was validated, with satisfactory precision and accuracy.
O gás natural veicular (GNV) é um derivado fóssil composto majoritariamente por hidrocarbonetos leves (metano, etano e propano), que tem grande importância energética para a sociedade moderna. Considerando a crescente demanda de GNV, se faz necessário, também, um efetivo controle da composição destes gases majoritários, que são os principais responsáveis pela eficiência energética deste combustível. A composição destes gases em GNV segue um determinado padrão de conformidade (faixa de controle) estabelecido pela ANP (Agência Nacional do Petróleo, Gás Natural e Biocombustíveis), de modo a garantir a eficiência energética do GNV comercializado no Brasil. Este trabalho propõe o desenvolvimento de uma metodologia para preparação automática de misturas gasosas padrões de metano, etano e propano, visando à determinação cromatográfica dos teores destes gases em GNV, empregando modelos de calibração elaborados e validados por análise de variância (ANOVA) e teste de recuperação. O sistema automático é do tipo dinâmico e é totalmente controlado por um programa de modo a preparar, conforme programado pelo usuário, misturas binárias de nitrogênio/metano, de nitrogênio/etano e de nitrogênio/propano, com teores (em fração mol/mol) que variam de modo a se obter bons modelos de calibração que contemplem as concentrações desses gases no GNV. A avaliação da metodologia por meio da ANOVA foi bastante satisfatória, os modelos construídos para os três gases metano, etano e propano apresentaram uma alta correlação (R2 > 0,99) e significância na regressão, e não demonstraram falta de ajuste e variação sistemática no gráfico dos resíduos. Os parâmetros de desempenho obtidos a partir dos modelos construídos tiveram limites de detecção menores que 10-2 e de quantificação menores que 10-1, a frequência de amostragem foi 4 amostras por hora. Um estudo de recuperação, envolvendo três misturas gasosas de composição certificada e uma amostra de Gás Natural Veicular (GNV), foi também realizado e os valores médios percentuais obtidos foram de 99,7 ± 3,1; 100,7 ± 4,4 e 98,0 ± 5,8 para o metano, etano e propano, respectivamente. Conclui-se com base nos valores de recuperação, bem como na ANOVA, que o método proposto foi devidamente validado, apresentando uma satisfatória precisão e exatidão.
Silveira, Valdelice Rodrigues da. "Estudo do desempenho de resinas polim?ricas para remo??o de H2S do g?s natural." Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17774.
Повний текст джерелаThe natural gas (NG) is a clean energy source and found in the underground of porous rocks, associated or not to oil. Its basic composition includes methane, ethane, propane and other components, like carbon dioxide, nitrogen, hydrogen sulphide and water. H2S is one of the natural pollutants of the natural gas. It is considered critical concerning corrosion. Its presence depends on origin, as well as of the process used in the gas treatment. It can cause problems in the tubing materials and final applications of the NG. The Ag?ncia Nacional do Petr?leo sets out that the maximum concentration of H2S in the natural gas, originally national or imported, commercialized in Brazil must contain 10 -15 mg/cm3. In the Processing Units of Natural Gas, there are used different methods in the removal of H2S, for instance, adsorption towers filled with activated coal, zeolites and sulfatreat (solid, dry, granular and based on iron oxide). In this work, ion exchange resins were used as adsorbing materials. The resins were characterized by thermo gravimetric analysis, infrared spectroscopy and sweeping electronic microscopy. The adsorption tests were performed in a system linked to a gas-powered chromatograph. The present H2S in the exit of this system was monitored by a photometrical detector of pulsing flame. The electronic microscopy analyzes showed that the topography and morphology of the resins favor the adsorption process. Some characteristics were found such as, macro behavior, particles of variable sizes, spherical geometries, without the visualization of any pores in the surface. The infrared specters presented the main frequencies of vibration associated to the functional group of the amines and polymeric matrixes. When the resins are compared with sulfatreat, under the same experimental conditions, they showed a similar performance in retention times and adsorption capacities, making them competitive ones for the desulphurization process of the natural gas
O g?s natural (GN) ? uma fonte de energia limpa encontrada no subsolo de rochas porosas, associado ou n?o ao petr?leo. Sua composi??o b?sica inclui metano, etano, propano e outros componentes, como di?xido de carbono, nitrog?nio, ?cido sulf?drico e ?gua. H2S ? um dos poluentes naturais do g?s natural. ? considerado cr?tico no que se refere ? corros?o. Sua presen?a depende da origem, bem como do processo usado no tratamento do g?s. Ele pode acarretar problemas nas tubula??es e aplica??es finais do GN. A Ag?ncia Nacional de Petr?leo estabelece que a concentra??o m?xima de H2S no g?s natural, de origem nacional ou importado, comercializado no Brasil contenha no m?ximo 10 15 mg/m3. Nas Unidades de Processamento do G?s Natutal, diferentes m?todos s?o usados na remo??o de H2S, por exemplo, em torres de adsor??o recheadas com carv?o ativo, ze?litas e Sulfatreat (s?lido, seco, granular e baseado em ?xido de ferro). Neste trabalho, resinas de troca-i?nica foram usadas como material adsorvente. As resinas foram caracterizadas por an?lise termogravim?trica, espectroscopia de infravermelho e microscopia eletr?nica de varredura. Os ensaios de adsor??o foram realizados em um sistema acoplado a um cromat?grafo a g?s. O H2S presente na sa?da do sistema foi monitorado por um detector fotom?trico de chama pulsante. As an?lises de microscopia eletr?nica demonstraram que a topografia e morfologia das resinas favorecem o processo de adsor??o. Caracter?sticas como comportamento macro, part?culas de tamanhos variados, geometrias esf?ricas, sem a visualiza??o de poros na superf?cie, foram encontrados. Os espectros de infravermelho apresentaram as principais freq??ncias de vibra??o associadas aos grupos funcionais das aminas e matrizes polim?ricas. Quando comparadas ao sulfatreat, sob as mesmas condi??es experimentais, as resinas demonstraram semelhante desempenho em tempos de reten??o e capacidade de adsor??o, tornando-se competitiva para o processo de dessulfuriza??o do g?s natural
Silveira, Valdelice Rodrigues da. "Estudo do desempenho de resinas polim?ricas para remo??o de H2S do g?s natural." Universidade Federal do Rio Grande do Norte, 2006. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17780.
Повний текст джерелаThe natural gas (NG) is a clean energy source and found in the underground of porous rocks, associated or not to oil. Its basic composition includes methane, ethane, propane and other components, like carbon dioxide, nitrogen, hydrogen sulphide and water. H2S is one of the natural pollutants of the natural gas. It is considered critical concerning corrosion. Its presence depends on origin, as well as of the process used in the gas treatment. It can cause problems in the tubing materials and final applications of the NG. The Ag?ncia Nacional do Petr?leo sets out that the maximum concentration of H2S in the natural gas, originally national or imported, commercialized in Brazil must contain 10 -15 mg/cm3. In the Processing Units of Natural Gas, there are used different methods in the removal of H2S, for instance, adsorption towers filled with activated coal, zeolites and sulfatreat (solid, dry, granular and based on iron oxide). In this work, ion exchange resins were used as adsorbing materials. The resins were characterized by thermo gravimetric analysis, infrared spectroscopy and sweeping electronic microscopy. The adsorption tests were performed in a system linked to a gas-powered chromatograph. The present H2S in the exit of this system was monitored by a photometrical detector of pulsing flame. The electronic microscopy analyzes showed that the topography and morphology of the resins favor the adsorption process. Some characteristics were found such as, macro behavior, particles of variable sizes, spherical geometries, without the visualization of any pores in the surface. The infrared specters presented the main frequencies of vibration associated to the functional group of the amines and polymeric matrixes. When the resins are compared with sulfatreat, under the same experimental conditions, they showed a similar performance in retention times and adsorption capacities, making them competitive ones for the desulphurization process of the natural gas
O g?s natural (GN) ? uma fonte de energia limpa encontrada no subsolo de rochas porosas, associado ou n?o ao petr?leo. Sua composi??o b?sica inclui metano, etano, propano e outros componentes, como di?xido de carbono, nitrog?nio, ?cido sulf?drico e ?gua. H2S ? um dos poluentes naturais do g?s natural. ? considerado cr?tico no que se refere ? corros?o. Sua presen?a depende da origem, bem como do processo usado no tratamento do g?s. Ele pode acarretar problemas nas tubula??es e aplica??es finais do GN. A Ag?ncia Nacional de Petr?leo estabelece que a concentra??o m?xima de H2S no g?s natural, de origem nacional ou importado, comercializado no Brasil contenha no m?ximo 10 15 mg/m3. Nas Unidades de Processamento do G?s Natutal, diferentes m?todos s?o usados na remo??o de H2S, por exemplo, em torres de adsor??o recheadas com carv?o ativo, ze?litas e Sulfatreat (s?lido, seco, granular e baseado em ?xido de ferro). Neste trabalho, resinas de troca-i?nica foram usadas como material adsorvente. As resinas foram caracterizadas por an?lise termogravim?trica, espectroscopia de infravermelho e microscopia eletr?nica de varredura. Os ensaios de adsor??o foram realizados em um sistema acoplado a um cromat?grafo a g?s. O H2S presente na sa?da do sistema foi monitorado por um detector fotom?trico de chama pulsante. As an?lises de microscopia eletr?nica demonstraram que a topografia e morfologia das resinas favorecem o processo de adsor??o. Caracter?sticas como comportamento macro, part?culas de tamanhos variados, geometrias esf?ricas, sem a visualiza??o de poros na superf?cie, foram encontrados. Os espectros de infravermelho apresentaram as principais freq??ncias de vibra??o associadas aos grupos funcionais das aminas e matrizes polim?ricas. Quando comparadas ao sulfatreat, sob as mesmas condi??es experimentais, as resinas demonstraram semelhante desempenho em tempos de reten??o e capacidade de adsor??o, tornando-se competitiva para o processo de dessulfuriza??o do g?s natural
Gunnarsson, Andreas. "Analysis of Alternative Fuels in Automotive Powertrains." Thesis, Linköping University, Department of Electrical Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-17053.
Повний текст джерелаThe awareness of the effect emissions have on the environment and climate has risen in the last decades. This has caused strict regulations of greenhouse gas emissions. Greenhouse gases cause global warming which may have devastating environmental effects. Most of the fuels commercially available today are fossil fuels. There are two major effects of using fuels with fossil origin; the source will eventually drain and the usage results in an increase of greenhouse gases in the atmosphere. Fuels that are created from a renewable feedstock are often referred to as alternative fuels and under ideal conditions they are greenhouse gas neutral, meaning that the same amount of greenhouse gases is released during combustion as the source of the fuel have absorbed during its growth period. This evaluation method is known as a well-to-wheel analysis which besides emissions also evaluates energy efficiencies during both the production and the combustion phases.
By evaluating results of well-to-wheel analyses along with fuel properties and engine concept characteristics, this report presents which driving scenario that is suitable for different powertrain configurations. For example, vehicles operating in high populated areas, as cities, have a driving scenario that includes low velocities and multiple stops while vehicles in low populated areas often travel long distances in higher speeds. This implies that different powertrains are suitable in different regions. By matching favorable properties of a certain powertrain to the properties important to the actual driving scenario this report evolves a fuel infrastructure that is suitable in Sweden.
İslamoğlu, Timur. "Impact of Post-Synthesis Modification of Nanoporous Organic Frameworks on Selective Carbon Dioxide Capture." VCU Scholars Compass, 2012. http://scholarscompass.vcu.edu/etd/454.
Повний текст джерелаSpagarino, Giorgio. "Low and medium temperature fuel cells: experimental tests and economic assessment." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/86/86131/tde-05022013-105641/.
Повний текст джерелаThis Masters dissertation aims to study technical potentialities of Fuel Cell technology, including the economical benefits that can provide compared with public grid as well. Thus, the dissertation has been focused in two main parts: the first concerns in an experimental approach to supply electrical power to the public grid using a Polymer Electrolyte Membrane Fuel Cell (PEMFC), while the second one presents a global (from an engineering and economic point-of-view) assessment of a Phosphoric Acid Fuel Cell (PAFC) for the co-generation of heat with electrical energy in Brazil. The first study has been accomplished connecting a PEMFC with a power inverter to the public grid. It has been proved experimentally that Fuel Cell is an alternative device that, as long as fuel is fed, may provide electrical energy continuously and more efficiently than traditional devices. The second study has been focused in the so-called Phosphoric Acid Fuel Cell (PAFC) that, being a Medium Temperature Fuel Cell, beyond to supply electrical energy, may be used for co-generation of thermal energy. Through this study it has been showed that, at the current state-of-art, PAFC is is not already a mature technology and it becomes economically viable only for niche market applications, represented by the industrial sectors with high base load power and continuous thermal energy demand. However, accumulated knowledge expressed by learning curve and natural gas shock price caused by possible LNG supplying and shale gas recovery are the two main factors that may turn investment in PAFC profitable worldwide.
Kolesnikov, Anton. "Experimental investigation of hydrocarbon formation and transformation under Earth´s upper mantle conditions." Doctoral thesis, KTH, Kraft- och värmeteknologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-27017.
Повний текст джерелаQC 20101203
Le, Van-Hoan. "Analyses de microvolumes de gaz par spectroscopie Raman : expériences quantitatives et modélisation des mélanges CO₂-CH₄-N₂." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0178.
Повний текст джерелаQuantitative knowledge of species trapped within fluid inclusions provides key information to better understand geological processes as well as to reconstruct the conditions of paleofluid circulation. CO₂, CH₄, and N₂ are among the most dominant gas species omnipresent in various geological environments, but their quantitative PVX calibration data are not fully established yet. Using the previously published data can therefore lead to non-quantified errors, especially when applied to geological fluids containing generally several substances at elevated pressure and density. The aim of this work is to provide accurate calibration data for the simultaneous determination of PVX properties of pure gases or any binary and ternary mixtures of CO₂, CH₄, and N₂ over 5 to 600 bars at a fixed temperature, directly from Raman spectra. For this, gas mixtures were prepared and compressed using a mixer (GasMix AlyTech) coupled with a homemade pressurization system. Raman in situ analyses of gas mixtures were performed at controlled conditions using an improved HPOC system (High-Pressure Optical Cell) with a transparent microcapillary containing the prepared gas mixtures, placed on a heating-cooling stage (Linkam CAP500). Overall, the uncertainty of the measurement of the PVX properties of fluid inclusions from our calibration equations at 22 or 32 °C is < ± 1 mol%, ~ ± 20 bars, and ~ ± 0.02 g.cm-³ for molar proportion, pressure and density, respectively. The ensuing aim of the project is to interpret the variation trends of the peak position of the CH₄ and N₂ ν1 band for an in-depth understanding. Two theoretical models, i.e., Lennard-Jones 6-12 potential energy approximation and Perturbed hard-sphere fluid model were involved to quantitatively assess the contribution of the attractive and repulsive intermolecular interaction forces to the pressure-induced frequency shifts. A predictive model was also provided to predict the variation trend of the CH₄ ν1 band over a pressure range up to 3000 bars as a function of pressure and composition. Furthermore, the applicability of our calibration data to other laboratories and apparatus and to gas mixtures that contain a small amount of other species (e.g., H2, H2S) was discussed and evaluated. New universal calibration data applicable for other laboratories were then provided. A computer program “FRAnCIs” was also developed to make the application of our calibration data as convenient as possible via a user-friendly interface
Guéret, Christophe. "Valorisation du méthane en hydrocarbures supérieurs par voie thermique : étude paramétrique et modèle cinétique." Vandoeuvre-les-Nancy, INPL, 1993. http://www.theses.fr/1993INPL010N.
Повний текст джерелаHernandez-Rodriguez, Guillermo. "Optimisation multiobjectif de réseaux de transport de gaz naturel." Thesis, Toulouse, INPT, 2011. http://www.theses.fr/2011INPT0067/document.
Повний текст джерелаThe optimization of a natural gas transportation network (NGTN) is typically a multiobjective optimization problem, involving for instance energy consumption minimization at the compressor stations and gas delivery maximization. However, very few works concerning multiobjective optimization of gas pipelines networks are reported in the literature. Thereby, this work aims at providing a general framework of formulation and resolution of multiobjective optimization problems related to NGTN. In the first part of the study, the NGTN model is described. Then, various multiobjective optimization techniques belonging to two main classes, scalarization and evolutionary, commonly used for engineering purposes, are presented. From a comparative study performed on two mathematical examples and on five process engineering problems (including a NGTN), a variant of the multiobjective genetic algorithm NSGA-II outmatches the classical scalararization methods, Weighted-sum and ε-Constraint. So NSGA-II has been selected for performing the triobjective optimization of a NGTN. First, the monobjective problem related to the minimization of the fuel consumption in the compression stations is solved. Then a biojective problem, where the fuel consumption has to be minimized, and the gas mass flow delivery at end-points of the network maximized, is presented. The non dominated solutions are displayed in the form of a Pareto front. Finally, the study of the impact of hydrogen injection in the NGTN is carried out by introducing a third criterion, i.e., the percentage of injected hydrogen to be maximized. In the two multiobjective cases, generic Multiple Choice Decision Making tools are implemented to identify the best solution among the ones displayed of the Pareto fronts
Шерстньов, Владислав Володимирович. "Автоматизована система керування технологічним процесом виробництва водню". Магістерська робота, Київський національний університет технологій та дизайну, 2021. https://er.knutd.edu.ua/handle/123456789/19249.
Повний текст джерелаДипломная магистерская работа посвящена усовершенствованию циклического процесса адсорбционного разделения газовой смеси с получением водорода, анализу математической модели технологического процесса производства водорода и обоснованию, разработке и исследованию автоматизированной системы управления технологическим процессом производства водорода. Исследованы модели, методы и алгоритмы автоматизированного управления, обеспечивающие получение водорода методом адсорбционного разделения газовых смесей с циклически изменяющимся давлением при выполнении заданных технологических ограничений. В исследованиях использовались методы системного анализа, математического моделирования, оптимизации, теории управления, теории процессов и аппаратов химической технологии. По результатам исследований разработана структура автоматизированной системы управления технологическим процессом производства водорода, проведено исследование закономерностей динамики адсорбционных процессов с циклическим изменением давления при воздействии различных возмущений и предложено применение адаптивной системы управления циклическим процессом адсорбционного разделения газовой смеси с получением водорода.
Thesis is devoted to improving the cyclic proccss of adsorption separation of a gas mixture with hydrogen production, analysis of the mathematical model of the technological proccss of hydrogen production and substantiation, development and research of an automated control system for the technological proccss of hydrogen production. Models, methods and algorithms of automated control, which provide hydrogen production by the method of adsorption separation of gas mixtures with cyclically variable pressure at performance of the set technological restrictions, are investigated. The research used methods of systems analysis, mathematical modeling, optimization, control theory, proccss theory and chemical technology. According to the research results, the structure of the automated control system of the hydrogen production proccss was studied, the regularities of the dynamics of adsorption processes with cyclic pressure change under different perturbations were studied and the application of the adaptive control system of the cyclic proccss of adsorption separation of gas mixture with hydrogen production was proposed.
Hales, Matthew Cameron. "Synthesis and characterisation of substituted smithsonite and calcite." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/16643/1/Matthew_Hales_Thesis.pdf.
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