The effects of changing nozzle hole patterns and hole geometry in a direct injection natural gas optically accessible engine was investigated. Six nozzles were studied having a 1 hole, 3 hole, and 9 hole pattern; each having either elliptical or circular hole geometries. Combustion images were taken with a high speed camera and the nozzles were compared on the basis of their ignition delay time, rate of heat release, net heat release, fuel utilization, gross indicated thermal efficiency, and particulate emissions. The best performance in all categories was achieved by the 9 hole nozzles which was largely attributed to better fuel mixing as a result of its hole distribution. The elliptical hole geometry exhibited characteristics of improved mixing mainly through reduced ignition delay time and reduced elemental carbon emissions.

This study addresses the problem of designing a new natural gas transmission network or expanding an existing network while minimizing the total investment and operating costs. A substantial reduction in costs can be obtained by effectively designing and operating the network. A well-designed network helps natural gas companies minimize the costs while increasing the customer service level. The aim of the study is to determine the optimum installation scheduling and locations of new pipelines and compressor stations. On an existing network, the model also optimizes the total flow through pipelines that satisfy demand to determine the best purchase amount of gas. A mixed integer nonlinear programming model for steady-state natural gas transmission problem on tree-structured network is introduced. The problem is a multi-period model, so changes in the network over a planning horizon can be observed and decisions can be made accordingly in advance. The problem is modeled and solved with easily accessible modeling and solving tools in order to help decision makers to make appropriate decisions in a short time. Various test instances are generated, including problems with different sizes, period lengths and cost parameters, to evaluate the performance and reliability of the model. Test results revealed that the proposed model helps to determine the optimum number of periods in a planning horizon and the crucial cost parameters that affect the network structure the most.

Catalytic combustion is an efficient method to reduce pollutant emissions produced by a variety of fuels. In this thesis, the use of iron pentacarbonyl (Fe(CO)5) as a catalyst precursor in the combustion of natural gas is experimentally studied. The counter-flow diffusion flame burner is employed as the experimental apparatus. The products of combustion are analyzed by using a Gas Chromatograph (GC) to quantitate the effects of adding the catalyst. The experimental setup is such that a mixture of methane (CH4) and nitrogen (N2) is fed from the bottom burner while a mixture of oxygen (O2) and air is supplied from the top burner. The combustion of natural gas without catalyst is first characterized. The oxidizer and fuel flow parameters are set up so that a stable, flat blue flame is formed close to the centre plane between the two burners upon ignition. The experimental results agree with the literature data and the numerical predictions from CHEMKIN software. To investigate and evaluate the performance of iron-containing catalysts on emission reduction, a small amount of separated nitrogen flow is used to carry iron pentacarbonyl into the flame through the central port of the fuel-side burner. Catalytic combustion produces an orange flame. Compared with the non-catalytic combustion data, it is found that carbon monoxide (CO) and soot precursor acetylene (C2H2) are reduced by 80% to 95% when 7453ppm iron pentacarbonyl is added.

This dissertation focuses on the spatial aspects of oil and natural gas production to investigate the extent and effects of inefficient and unnecessary spatial competition. Because oil and natural gas are migratory, operators can cause hydrocarbon resources to flow from a neighboring property onto his or her own through rapid extraction. This problem is compounded when productive leases are comparatively small, as is the case in Texas. Following an introduction and literature review, the third chapter takes advantage of a natural experiment to demonstrate how spillovers in production limit total cumulative recovery, and how the assignment of secure property rights can enhance economic outcomes. The chapter examines production from wells in Oklahoma and Texas near the panhandle border. While wells on either side of this line have similar geologies and so should be similarly productive they are exposed to different treatments: Oklahoma has a much higher rate of unitization (a contractual scheme where competing owners hire a common operator and share profits), whereas the unitization rate in Texas is lower. Using regression discontinuity design, I find that Oklahoma wells are produced more slowly early on, and that this results in greater cumulative recovery over the course of a well’s life (150% more relative to Texas). These results are robust after controlling for reservoir specific effects, and across parametric, semi-parametric and nonparametric specifications. xiiThe fourth chapter quantifies the degree to which competing owners interfere with each other’s production through spatial spillovers. I use a spatial econometric model that controls for spatial autocorrelation and spatial dependence and can therefore identify the spillovers in production. Additionally, by comparing leases owned by competing producers to leases owned by a common producer, I show empirically how securing property rights through common ownership can alleviate the externality in production. A priori, one would expect that when a common producer owns adjacent leases, the producer has the incentive to fully account for how spillovers in production affect neighboring wells. Conversely, when adjacent landowners are in competition to extract the resource, they will not account for the damage rapid production causes at neighboring wells. After controlling for secondary injection I find that this is indeed the case for Slaughter field of West Texas. The fifth chapter investigates the statistical properties of oil and natural gas production. I find striking evidence that both oil and natural gas production are power-law distributed with the exponent approximately equal to one. This distribution might arise from disequilibrium in production and exploration. Highlighting this distribution is important because it has potential consequences for the political economy of regulation as well as for resource management. For example, because the most productive wells lie in the far-right tail of the distribution, regulation geared to prevent a Deepwater Horizon scale spill need fall on a vanishingly small percent of wells. The distribution also has consequences for management because a company profitability depends disproportionately on how it manages its most productive wells. The sixth chapter provides a short conclusion.

Ideologies, intellectually and religiously driven, color both politics and economics. The relationship between government and the governed, human rights and the rule of law all are affected by such ideologies. However, unless humans are willing to change dramatically lifestyles honed in hundreds of years of historic developments, energy and energy abundance are arguably the most critical needs of modern society. In many ways energy has transcended ideology although there are still unrepentant ideologues advocating otherwise. It was this realization, augmented by a few events, that brought about the writing of The Color of Oil. The authors felt a need to combat popular errors being promulgated by the media in an area of such great importance to the entire human enterprise: Energy. A nonsensical 1999 cover story by the usually reliable Economist magazine provided the last straw. Someone had to set the record straight. But the dour-to-hostile climate that surrounded oil and energy at the turn of the century presented certain challenges to getting the work published. As it turned out, the unique qualifications of a science and technology journalist, the author of this thesis, played a key role in making the publication a reality, and then a phenomenon of sorts. In some ways, The Color of Oil suggests a meaningful new role for science and technology journalism and journalists in a media environment driven by movie stars and media profits. The book was produced on a short timeline and with limited resources. The book's message has played a role in key political decisions in the United States and around the world; as a direct result of the book, the authors were invited and participated extensively in development of energy policy in Texas and at the national level. It has effected billions of dollars of commercial enterprise, providing as it did the blueprint for development of Cheniere Energy, Inc., a $2 billion Houston company that today is one of North America's premier LNG receiving companies. And testimonies from readers of The Color of Oil suggest that the book has produced meaningful personal wealth for many of its 30,000-plus readers.

Thesis (M.S. in E.A.S.)--School of Earth and Atmospheric Sciences, Georgia Institute of Technology, 2004. Directed by Daniel Lizarralde. / Includes bibliographical references (leaves 69-73).

Abstract TECO advertisements promote the use of natural gas as an energy source because it claims that natural gas is an environmentally responsible alternative to other sources of energy. However, these advertisements do not reveal the not-so-green process, namely hydraulic-fracturing, or fracking, by which natural gas is produced and the consequences that it can and does have on public health and the environment. Even though the conversation about fracking has been on the rise in recent years as certain companies and politicians have pushed for an increase in natural gas production, scholars have yet to examine the communicative strategies used by energy companies, such as TECO, to disregard the environmental dangers associated with fracking and present natural gas extraction as both environmentally friendly and safe for consumers. Although there are numerous ways of analyzing the relationship between communication and greenwashing, I chose to examine the rhetorical choices, both written and spoken, and image choices embedded in TECO's greenwashing advertisements for natural gas. The use of communicative strategies in TECO's advertisements aim to create a dominant discourse of green consumerism, which works to shape society's understanding of what it means to be a consumer who strives to be environmentally responsible. My analysis was informed by Stuart Hall's theory of Encoding and Decoding (1973) and his theory of representation (1997). I argue that TECO presents the dominant code of the green consumer and my analysis offers an oppositional reading. The use of grounded theory provided me with a viable method to analyze TECO's advertisements because I was able gather and analyze data from ten commercial advertisements, examine each individually for themes, and then discuss the ways in which TECO uses specific language, both written and spoken, and visual images, in its advertisements, in order to construct the meaning of natural gas and the identity of the natural gas consumer.

A competitive gas-to-gas trading market has yet to emerge in Asia. Yet in spite of the various barriers and restrictions, the trend of liberalization seems to inevitable. How a natural gas trading market just might develop in East Asia is what this thesis explains and predicts. Moreover, it lays out what the preconditions for the changes are, and what the costs and benefits from such changes may be. Considering Asia’s current market situation, the wholesale competition model could be a practical option for Asia’s gas markets. A critical role in building up the gas-to-gas trading market will be played by China. In the first stage of market liberalization, China alone can be expected to form its own trading hub on its east coast, say in Shanghai. If the transactions of the trading hub work smoothly and the set prices lower than oil-linked gas prices, then other gas-importing countries would likely join the trading hub by interconnecting with a physical pipeline. / text

Natural gas is at the core of the energy supply and security debates; new extraction technologies, such as horizontal drilling and hydraulic fracturing, have expanded natural gas production. As with any energy system, however, natural gas has an environmental footprint and this thesis examines the air quality impacts of natural gas production. Greenhouse gas (GHG), criteria pollutant, and toxic emissions from natural gas production have been subject to a great amount of uncertainty, largely due to limited measurements of emission rates from key sources. This thesis reports direct and indirect measurements of emissions, assessing the spatial and temporal distributions of emissions, as well as the role of very high emitting wells and high emitting sources in determining national emissions. Direct measurements are used to identify, characterize and classify the most important sources of continuous and episodic emissions, and to analyze mitigation opportunities. Methods are proposed and demonstrated for reconciling these direct measurements of emissions from sources with measurements of ambient concentrations. Collectively, the direct source measurements, and analyses of ambient air pollutant measurements in natural gas production regions reported in this work improve the estimation, characterization, and methods for monitoring air quality implications of shale gas production. / text

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