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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.
61

Remote Sensing of Forest Structural Changes due to Shale Gas Extraction in Muskingum Watershed

Liu, Yang January 2018 (has links)
No description available.
62

Molecular dynamics studies on shale gas and fracturing fluid diffusivity in shales

Peristeras, Loukas D., Papavasileiou, Konstantinos D., Economou, Ioannis G. 12 July 2022 (has links)
No description available.
63

New Polygeneration Processes for Power Generation and Liquid Fuel Production with Zero CO2 Emissions

Khojasteh Salkuyeh, Yaser 06 1900 (has links)
The price and accessibility of fossil fuels, especially crude oil, are subject to considerable fluctuations due to growing demand on energy, limited resources, and energy security concerns. In addition, climate change caused by burning of fossil fuels is a challenge that energy sector is currently facing. These challenges incentivize development of alternative processes with no greenhouse gas emissions that can meet transportation fuels, chemical liquids, and electricity demands. Coal-based processes are of particular interest because coal price is both low and stable. However, these processes have a large environmental impact and are also less economically attractive than natural gas based plants due to the recent significant drop in natural gas price. However, even for natural gas plants, attempts to reduce CO2 emissions by using traditional CO2 capture and sequestration technologies not only decrease the thermal efficiency and profitability of the plant significantly but still release some CO2 to the atmosphere. The aim of this thesis is to develop, simulate and optimize an integrated polygeneration plant that uses multiple feedstocks and produces multiple products with low to zero CO2 emissions. Several process alternatives are investigated in this work to show the effect of each feedstock and product on the performance of the proposed plant. A comprehensive study is performed in each section, including process simulation in Aspen Plus software, development of custom models required for some units, as well as cost analysis by using Aspen Icarus software and empirical cost estimations from literature. Moreover, derivative free optimization techniques such as particle swarm optimization (PSO), genetic algorithm (GA) and simulated annealing (SA) are implemented to drive the design to economically optimum conditions as a function of the market price and carbon taxes. The final model will also introduce emerging technologies that can achieve higher efficiency and lower CO2 emissions compared to commercial systems, such as chemical looping gasification, chemical looping combustion, nuclear heat reforming, etc. By integrating multiple feedstocks and processes, the model can exploit certain synergies which are unavailable to traditional plants, resulting in significant efficiency improvements. In addition to power and liquid fuels, this polygeneration process offers benefits for petrochemical plants. Despite limited worldwide crude oil reserves, the demand for petrochemical products is still growing fast and it is highly important for petrochemical industry to find new resources as feedstock and diversify their supply chain network. By integration of the polygeneration plant in the same facility with novel processes that produce olefins (petrochemical feedstock) not from oil, but from syngas, it is possible to supply the required feed at lower cost than commercial steam cracking plants. / Thesis / Doctor of Philosophy (PhD)
64

Cultivation of Nannochloropsis salina and Dunaliella tertiolecta Using Shale Gas Flowback Water and Anaerobic Digestion Effluent as Cultivation Medium

Racharaks, Ratanachat 30 December 2014 (has links)
No description available.
65

Analysis of the Point Pleasant/Lexington/Trenton Formations: Sulfides, Mineralogy, and Trace Elements as Geochemical Proxies

Foley, Derek J. January 2016 (has links)
No description available.
66

How Robust is the Governance System of British Columbia for Regulating the Environmental Aspects of Shale Gas Development?

Elfving, Sanna 06 1900 (has links)
Yes / This paper focuses on the robustness of the regulatory system of British Columbia (BC) from the environmental point of view. It argues that the enforcement of existing regulations is effective due to the active monitoring of compliance by the provincial oil and gas regulator. The regulator has a key role in promoting transparency, public participation and safety and sustainability of shale gas operations. The paper argues that although certain elements in the provincial legislative framework are covered by non-binding guidelines, rather than legislation, the regulator has responded to many of the concerns raised by the public over the shale gas development in BC, including impacts on regional air quality, fresh water contamination and access to water, deforestation, biodiversity and induced seismicity. The regulator has also recognized several key issues, such as baseline water monitoring as an issue requiring further research. This paper concludes that BC has one of the most robust regulatory systems in North America for regulating hydraulic fracturing.
67

The Ecca type section (Permian, South Africa) : an outcrop analogue study of conventional and unconventional hydrocarbon reservoirs

Campbell, Stuart Alexander January 2015 (has links)
The Karoo Basin of South Africa holds an estimated 906 billion to 11 trillion cubic meters of unconventional shale gas within the shales of the Whitehill and Collingham formations of the Ecca Group. Evaluation of this potential resource has been limited due to the lack of exploration and a scarcity of existing drill core data. In order to circumnavigate this problem this study was undertaken to evaluate the potential target horizons exposed in outcrops along the southern portion of the Karoo Basin, north of Grahamstown in the Eastern Cape Province. Detailed field logging was done on the exposed Whitehill and Collingham formations as well as a possible conventional sandstone (turbidite) reservoir, the Ripon Formation, along road cuttings of the Ecca Pass. Palaeocurrent data, jointing directions and fossil material were also documented. Samples were analysed for mineralogy, porosity, permeability, and total organic carbon content (TOC). The extensively weathered black shales of the Whitehill Formation contain a maximum TOC value of 0.9% and the Collingham Formation shales contain a maximum TOC value of 0.6%. The organic lithic arkose sandstones of the Ripon Formation are classified as ‘tight rock’ with an average porosity of 1% and an average permeability of 0.05 mD. The Whitehill Formation in the southern portion of the Karoo Basin has experienced organic matter loss due to low grade metamorphism as well as burial to extreme depths, thus reducing shale gas potential. The Ripon Formation is an unsuitable conventional reservoir along the southern basin boundary due to extensive cementation and filling of pore spaces.
68

Well Water Quality in Southern Butler County, Pennsylvania

Mayes, Scott 18 May 2016 (has links)
The increase in unconventional shale gas extraction in Pennsylvania has resulted in an increased number of groundwater contamination claims. Well water quality was investigated in southern Butler County, PA where 387 unconventional gas wells have been drilled since 2006. A total of 121 households participated in a survey and 238 well water samples were tested. Specific conductivity, pH, and dissolved oxygen in these samples were measured in the field and seven anion concentrations and thirty metal concentrations were measured in the lab. A subset of 91 water wells was also tested for light hydrocarbons (methane, ethane, ethylene, propylene, propane, butane). Pennsylvania DEP file reviews were used to create GIS maps indicating legacy oil and gas, unconventional wells, and plot water testing results. Results indicate few wells had high quality groundwater, with 86% containing one or more contaminants above (secondary) Maximum Contaminant Levels, with manganese (56%), iron (47%), fluoride (18%), TDS (18%), pH (17%), aluminum (17%) the most common. / Bayer School of Natural and Environmental Sciences; / Environmental Science and Management (ESM) / MS; / Thesis;
69

Expertise Revisited: Reflecting on the Intersection of Science and Democracy in the Case of Fracking

Ahmadi, Mahdi 12 1900 (has links)
This dissertation aims to explain the conditions under which expertise can undermine democratic decision making. I argue that the root of the conflict between expertise and democracy lies in what I call insufficiently “representative” expertise – that is forms of scientific research that are not relevant to the policy questions at hand and that fail to make visible their hidden values dimensions. I claim that the scholarly literature on the problem of expertise fails to recognize and address the issue correctly, because it does not open the black box of scientific methodologies. I maintain that only by making sense of the methodological choices of experts in the context of policy making can we determine the relevance of research and reveal the hidden socio-political values and consequences. Using the case of natural gas fracking, I demonstrate how expert contributions – even though epistemically sound – can muddle democratic policy processes. I present four case studies from controversies about fracking to show how to contextualize scientific methodologies in the pertinent political process. I argue that the common problem across all case studies is the failure of expertise to sufficiently represent stakeholders’ problems and concerns. In this context, “representation” has three criteria: (1) the operational research questions on which the qualified experts work are relevant to stakeholders’ problems and concerns; (2) the non-epistemic values and consequences of epistemic choices of experts are compatible with social and political values and priorities; and (3) hidden values attached to facts are fully transparent and openly debated. In the conclusion, I propose a normative version of this representation theory that can be used to evaluate the appropriateness of expertise for democratic policy making. Instead of the value-free science ideal, I propose a new ideal to legitimately allow non-epistemic values in scientific reasoning without compromising the soundness of research.
70

Hydraulic fracturing and shale gas extraction

Klein, Michael January 1900 (has links)
Master of Science / Department of Chemical Engineering / James Edgar / In the past decade the technique of horizontal drilling and hydraulic fracturing has been improved so much that it has become a cost effective method to extract natural gas from shale formations deep below the earth’s surface. Natural gas extraction has boomed in the past few years in the United States, enough that it has driven prices to an all time low. The amount of natural gas reserves in the U.S. has led to claims that it can lead the country to energy independence. It has also been touted as a cleaner fuel for electricity generation and to power vehicles. This report explains hydraulic fracturing and horizontal drilling particularly with regards to utilizing the techniques for natural gas extraction from shale gas. It also discusses the environmental impact due to the drilling and gas extraction. It demonstrates that although the natural gas beneath the U.S. is a valuable resource, the impacts to the planet and mankind are not to be taken lightly. There is the potential for the effects to be long term and detrimental if measures are not taken now to control them. In addition although on the surface natural gas seems to be a greener fuel, particularly in comparison to gasoline, it is also considered worse for the environment.

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