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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.
21

Investigation into the importance of geochemical and pore structural heterogeneities for shale gas reservoir evaluation

Ross, Daniel John Kerridge 05 1900 (has links)
An investigation of shale pore structure and compositional/geochemical heterogeneities has been undertaken to elucidate the controls upon gas capacities of potential shale gas reservoirs in northeastern British Columbia, western Canada. Methane sorption isotherms, pore structure and surface area data indicate a complex interrelationship of total organic carbon (TOC) content, mineral matter and thermal maturity affect gas sorption characteristics of Devonian-€”Mississippian (D-€”M) and Jurassic strata. Methane and carbon dioxide sorption capacities of D-€”M shales increase with TOC content, due to the microporous nature of the organic matter. Clay mineral phases arealso capable of sorbing gas to their internal structure; hence D-€”M shales which are both TOC- and clay-rich have the largest micropore volumes and sorption capacities on a dry basis. Jurassic shales, which are invariably less thermally mature than D-€”M shales, do not have micropore volumes which correlate with TOC. The covariance of methane sorption capacity with TOC, independent of micropore volume, indicates a solute gas contribution (within matrix bituminite) to the total gas capacity. On a wt% TOC basis, D-M shales sorb more gas than Jurassic shales: a result of thermal-maturation induced, structural transformation of the D-€”M organic fraction. Organic-rich D-€”M strata are considered to be excellent candidates for gas shales in Western Canada. These strata have TOC contents ranging between 1-5.7 wt%, thermal maturities into the dry-gas region, and thicknesses in places of over 1000 m. Total gas capacity estimates range between 60 and 600 bcf/section where a substantial percentage of the gas capacity is free gas, due to high reservoir temperatures and pressures. Inorganic material influences modal pore size, total porosity and sorption characteristics of D-M shales. Carbonate-rich samples often have lower organic carbon contents (oxic deposition) and porosity, hence potentially lower sorbed and free-gas capacities. Highly mature Devonian shales are both silica and TOC-rich (up to 85% quartz and 5 wt% TOC) and as such, deemed excellent potential shale gas reservoirs because they are both brittle (fracable), and gas-charged. However, quartz-rich Devonian shales display tight-rock characteristics, with poorly developed fabric, small median pore diameters and low permeabilities. Hence potential `frac-zones' will require an increased density of hydraulic fracture networks for optimum gas production.
22

Investigation into the importance of geochemical and pore structural heterogeneities for shale gas reservoir evaluation

Ross, Daniel John Kerridge 05 1900 (has links)
An investigation of shale pore structure and compositional/geochemical heterogeneities has been undertaken to elucidate the controls upon gas capacities of potential shale gas reservoirs in northeastern British Columbia, western Canada. Methane sorption isotherms, pore structure and surface area data indicate a complex interrelationship of total organic carbon (TOC) content, mineral matter and thermal maturity affect gas sorption characteristics of Devonian- Mississippian (D- M) and Jurassic strata. Methane and carbon dioxide sorption capacities of D- M shales increase with TOC content, due to the microporous nature of the organic matter. Clay mineral phases arealso capable of sorbing gas to their internal structure; hence D- M shales which are both TOC- and clay-rich have the largest micropore volumes and sorption capacities on a dry basis. Jurassic shales, which are invariably less thermally mature than D- M shales, do not have micropore volumes which correlate with TOC. The covariance of methane sorption capacity with TOC, independent of micropore volume, indicates a solute gas contribution (within matrix bituminite) to the total gas capacity. On a wt% TOC basis, D-M shales sorb more gas than Jurassic shales: a result of thermal-maturation induced, structural transformation of the D- M organic fraction. Organic-rich D- M strata are considered to be excellent candidates for gas shales in Western Canada. These strata have TOC contents ranging between 1-5.7 wt%, thermal maturities into the dry-gas region, and thicknesses in places of over 1000 m. Total gas capacity estimates range between 60 and 600 bcf/section where a substantial percentage of the gas capacity is free gas, due to high reservoir temperatures and pressures. Inorganic material influences modal pore size, total porosity and sorption characteristics of D-M shales. Carbonate-rich samples often have lower organic carbon contents (oxic deposition) and porosity, hence potentially lower sorbed and free-gas capacities. Highly mature Devonian shales are both silica and TOC-rich (up to 85% quartz and 5 wt% TOC) and as such, deemed excellent potential shale gas reservoirs because they are both brittle (fracable), and gas-charged. However, quartz-rich Devonian shales display tight-rock characteristics, with poorly developed fabric, small median pore diameters and low permeabilities. Hence potential `frac-zones' will require an increased density of hydraulic fracture networks for optimum gas production. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
23

Potenciál břidlicového plynupro energetiku EU / Potential of shale gas for EU

Kloz, Ondřej January 2012 (has links)
This diploma thesis determines potential benefit of shale gas and its influence on price of gas on European market. For this purpose was chosen two variants, which have the best chance to decrease price of gas on European market. The first variant is extraction of shale gas directly in Europe. The size of deposits and cost estimates indicates the biggest potential from both variants. Possible extraction could be able to decrease significantly price of gas on European market. Nevertheless the present attitude of Europe to extraction can limit this potential. The second variant is import of LNG, which have already helped to decrease price of gas significantly in many European countries. Nevertheless its possible influence on price decline of gas is limited. Expenditures connected with LNG prevent to greater price decline on the possible level of extraction. Moreover Europe has to face to great competition from Asia, where considerable part of gas supply move to. Final benefit of LNG will depend mostly on the size of available supply.
24

Impact of Technology on U.S. natural gas industry / Dopad technológií na sektor zemného plynu v USA

Zelenická, Petra January 2013 (has links)
The aim of the thesis is to describe structural changes in the U.S. natural gas industry after implementation of hydraulic fracturing method which exploit natural gas from shale. In order to provide a complex description; environmental, market impacts and political interests are taken into consideration. Consequently, cluster analysis looks for a change in relations among various factors arising on the market. Tested periods are carefully chosen according to market events and results of statistical tests. One may conclude, it is a complexity of market, technology improvement and government behaviour which influence natural gas industry in USA.
25

Developing the Shale Gas Industry in South Africa : an analysis of the environmental legal framework

Sibiya, Zwelethu January 2014 (has links)
Dissertation (LLM)--University of Pretoria, 2014. / gm2015 / Centre for Human Rights / Unrestricted
26

A study of the non-tax fiscal regime for shale gas development in South Africa

Jali, Nhlanhla Providence January 2019 (has links)
South Africa is pursuing the exploration and exploitation of its possible petroleum resources particularly shale gas, following the estimation of just over 400 trillion cubic feet (tcf) of shale gas resources in the Karoo region. This, including the lodgement of five shale gas exploration right applications has necessitated the strengthening of the petroleum regulatory framework as well as the fiscal regime to ensure that South Africa remains an attractive destination for investors and for South Africa to extract maximum economic benefits. This paper has undertaken an examination of the current fiscal regime particularly the non-tax elements as stipulated in the current regulatory framework. Upon its face value the South African fiscal regime appears to be underdeveloped and not necessarily designed to cater for development of shale gas. Furthermore, it is not designed to address the specifics of shale gas development within the South African context. Some aspects of the South African fiscal regime may require to be strengthened while also remaining relevant and competitive internationally. A fiscal regime that is flexible and sensitive to shale gas development specific within a country context is required. Consideration for a differentiated tax construction may also be incorporated to make up for allowances provided at the beginning of the project. This will be in line with South Africa’s objectives for the creation of a sustainable and competitive petroleum industry that provides a win-win solution for both government and the industry. / Mini Dissertation (LLM)--University of Pretoria, 2019. / Public Law / LLM / Unrestricted
27

Reglering av fracking i EU - en aktörsanalys / The regulatory framework development for shale gas in the EU – an ANT analysis

Stenström, Oscar January 2014 (has links)
Hydraulisk spräckning – i debatten omnämnd som fracking – är en kontroversiell energiteknik som väckt starka känslor. Genom att borra horisontella cementrör i skifferformationer och sedan påföra en kemikaliespetsad vattenblandning under tryck har bunden gas kunnat utvinnas. Fracking medför en rad miljörisker och adderar ett nytt fossilt bränsle i en tid när världen står i behov av att lämna den fossila eran. Tekniken har mellan åren 2010-2013 påverkat den globala energisituationen i allmänhet och den amerikanska marknaden i synnerhet. EU:s strävan att kopiera the US shalegas-revolution innebar att en komplicerad teknikdebatt tog fart under 2012. Energisystem är bärare av en bred uppsättning värderingar varpå samhället vilar och utvecklas. Med hjälp av aktörs-nätverksteorin (ANT) har jag kartlagt aktörer och aktörsnätverkens utveckling i EU kring fracking under år 2013. Studien gör en fördjupning av utvecklingen i Sverige och jämför med Polen och Frankrike. I Sverige och i synnerhet Frankrike har de lokala mikro-aktörerna varit framgångsrika i att bilda aktörsnätverk och lyckats beskriva teknikens negativa påverkan. I Frankrike finns ett nationellt förbud mot fracking som åtnjuter brett stöd. I Polen där ett nationellt energioberoende är avgörande på nationell makro-nivå är stödet för fracking solitt. Utvecklingen av aktörsnätverken i USA har haft stor påverkan på den europeiska utvecklingen. I EU lyckades inte de aktörsnätverk som stred för en hårdare reglering att övertyga kommissionen att föreslå ny lagstiftning. Kommissionen föreslog, i strid mot Europaparlamentet, endast icke-bindande rekommendationer för fracking i EU. I Sverige har de lokala aktörerna lyckats med många översättningar och de har expanderat sitt aktörsnätverk så mycket att fracking sannolikt inte kommer i fråga. För utvecklingen av samtliga aktörsnätverk har vatten varit den artefakt som alla aktörer har tvingats förhålla sig till. Fracking kräver stora volymer vatten, förorenar vatten, påverkar det omkringliggande vattentäkterna och kräver transport av vatten. Vatten är en tydlig obligatorisk passagepunkt för fracking. / Hydraulic fracturing – fracking – is a controversial technology that generates strong feelings. Hydraulic fracturing is horizontal drilling and fracturing of shale rock by a pressurized liquid with water, sand and chemicals. Fracking involves a number of environmental hazards, and adds a new fossil fuel at a time when the world needs to leave the fossil fuel era. Fracking has between 2010 and 2013 affected the global energy policy in general and the U.S. market in particular. A complex technology debate took off in 2012 when European Union desire to copy the U.S. shale gas revolution. Energy politics is a carrier of a broad set of values upon which society is based and developed. With the help of the actor–network theory (ANT) I have mapped the development for actors and networks in the EU on fracking in 2013. The study describes the development in Sweden and compare with Poland and France. In Sweden and especially France, the local micro-actors have been successful in developing networks which has spread knowledge of the negative impacts of fracking. France got a broad support behind the national moratorium against fracking. In Poland, where the national energy dependency is of crucial macro importance the support for fracking is overwhelming. The development of actor-networks in the U.S. has had a major impact on the development in EU. In Europe the network who fought for stricter regulations failed. The Commission only enforced non-binding recommendations on fracking against the will of the European Parliament. In Sweden, the local actors succeeded with many translations and expanded its network which implies that fracking is not likely to expand. In all networks, water has been the artifact that all actors have had to address. Fracking requires large volumes of water, pollute the water, affects the surrounding water sources and require transportation of water. Water has become an obligatory passage point for fracking.
28

Desorption and Adsorption of Subsurface Shale Gas

Xiong, Fengyang January 2020 (has links)
No description available.
29

Nature of Solid Organic Matters in Shale

Wu, Xinyang January 2013 (has links)
No description available.
30

Influência da temperatura na geração biogênica de metano e dióxido de carbono na formação Irati, permiano da bacia do Paraná / not available

Almeida, Nazaré da Silva 19 April 2018 (has links)
Metano (CH4) e dióxido de carbono (CO2) são gases de grande importância climática e energética, pois contribuem para o efeito de estufa, mas também para produção de energia, no caso do CH4. Do ponto de vista energético, reconhecer as diferentes fontes de geração de CH4 torna-se um fator crucial na avaliação das reservas mundiais de gás natural, uma vez que as estimativas atuais de reservas potenciais não levam em consideração as diferentes origens dos hidrocarbonetos presentes ou, na grande maioria, considera apenas a origem termogênica. A temperatura é um dos fatores mais importantes que afetam o crescimento microbiano e as reações biogeoquímicas ligadas à metanogênese. A Formação Irati (Permiano da Bacia do Paraná) ocorre na região sul da América do Sul e representa um dos folhelhos orgânicos mais importantes do mundo já que o conteúdo em carbono orgânico total (COT) atinge até 23% e cobre uma área de aproximadamente 700.000 km2. A história térmica deste importante reservatório de carbono é atípica por hospedar rochas ígneas do Cretáceo. Isto proporcionou a ocorrência de zonas termicamente imaturas até zonas com maturidade suficiente para a geração termogênica de CH4. Este estudo trata da influência da temperatura na geração de CH4 e CO2 biogênicos em folhelhos da Formação Irati. Para isto, amostras de folhelho foram utilizadas em experimentos de incubação realizados sob diferentes temperaturas (22°C, 50°C, 70°C e 80°C), com objetivo de avaliar a influência das condições térmicas sobre a geração biogênica de CH4 e CO2. Temperaturas mais elevadas promoveram maiores taxas de produção de CH4 e CO2. A produção biogênica de CH4 mostrou-se mais eficiente em condições de temperatura de 80°C, com um rendimento máximo de 2,45 ml/t.d em comparação com 0,49 ml/t.d a 22°C, 1,75 ml/t.d e 2,09 ml/t.d a 50°C e 70°C, respectivamente. A mesma tendência foi observada para o CO2. O potencial de produção máximo de CO2 foi observado sob condições térmicas de 80°C, atingindo 23467,37 ml/t.d. As diferenças de produção obtidas para as diferentes amostras analisadas parecem estar relacionadas com a composição química da matriz mineral, observando-se maior produção em amostras com maior quantidade de enxofre (S), quando submetidas a altas temperaturas (50°C, 70°C e 80°C). Além dos folhelhos da Formação Irati, níveis orgânicos das formações Água de Madeiros e Vale das Fontes, Jurássico da Bacia Lusitânica, foram também estudados, os quais são termicamente imaturos e apresentam querogênio tipicamente marinho, distinto do observado na Formação Irati. O aumento da geração biogênica de CH4 e CO2 com a elevação da temperatura também foi observado para amostras das formações Água de Madeiros e Vale das Fontes. Com o presente estudo, é quebrado o paradigma de que 80°C seria a temperatura máxima para a ocorrência de metanogênese em bacias sedimentares, ou reservatórios. Assim, a geração biogênica de CH4 é favorecida por temperaturas mais elevadas (até no mínimo 80°C), considerando-se que a microbiota dos experimentos decorridos durante o presente trabalho seria similar aquelas que ocorrem em bacias sedimentares, bem como o ecossistema. Este trabalho constitui o primeiro estudo que avaliou o efeito da temperatura na produção de gases de origem biogênica em folhelhos da Formação Irati (Bacia do Paraná) e das formações Água de Madeiros e Vale das Fontes (Bacia Lusitânica - Portugal). / Methane (CH4) and carbon dioxide (CO2) have great environmental and economic importance due to their contribution to the greenhouse effect and climate change, but also as energy resource, in the case of CH4. From the energy point of view, recognizing the different sources of CH4 in sedimentary basins has a crucial factor in assessing the world\'s natural gas reserves, since the current estimates of hydrocarbons accumulations in sedimentary basins are based on thermogenic generation of hydrocarbons. However, few studies evaluate the importance of CH4 and CO2 generation as a product of organic matter biodegradation in sedimentary basins. This issue has great relevance to improve the estimates about the geological accumulations of CH4 and CO2. Temperature is one of the most important factors affecting microbial growth and biogeochemical processes responsible for CH4 and CO2 generation in subsurface environments. In this context, the Irati Formation (Permian of the Paraná Basin) in southern of South America represents one of the most organicrich shale around the world, reaching up to 23% of total organic carbon (TOC) and covering an area of approximately 700.000 km2. The thermal history of this important geological carbon pool is atypical because of the emplacement of igneous bodies during the Early Cretaceous. In this study, shale samples of the Irati Formation were used in incubation experiments performed under different temperatures (22°C, 50°C, 70°C and 80°C) to evaluate the influence of thermal conditions on biogenic generation of CH4 and CO2. Higher temperatures promoted higher production rates of CH4 and CO2. Biogenic CH4 production was more efficient when shale samples were incubated at 80°C, with a maximum yield of 2.45 ml/t.d compared to 0.49 ml/t.d at 22°C, 1.75 ml/t.d at 50°C and 2.09 ml/t.d at 70°C. The same trend was observed for CO2 generated as by-product of methanogenesis. The maximum production for CO2 was observed at 80°C, reaching 23467.37 ml/t.d. The differences in CH4 and CO2 production observed for different analyzed samples seem to be related to the composition of the mineral matrix, being observed higher production in samples with higher amount of sulfur. Additionaly, organic layers of the Água de Madeiros and Vale das Fontes Formations (Lusitanian Basin), which are thermally immature and present typically marine kerogen, were also submitted to incubation experiments to evaluate CH4 and CO2 generation. Higher biogenic generation of CH4 with the elevation of temperature was also observed for the Água de Madeiros and Vale das Fontes Formations. This suggests that biogenic CH4 generation is favored by higher temperatures, at least until 80°C, independent of the thermal maturity of the substrate, pointing that the temperature window (and depth zone) for the generation of biogenic CH4 in sedimentary basins is larger than suggested in previous studies.

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