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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.
191

Prices and shortages : evaluating policy options for the natural gas industry

Pindyck, Robert S. January 1977 (has links)
No description available.
192

Mezinárodně-politický a ekonomický aspekt ruského zemního plynu / International Political and Economic Aspect of Russian Natural Gas

Katolická, Sylvie January 2009 (has links)
The master thesis analyzes the current situation in the Russian gas industry and outlines the outlook for 2020 with regard to the interaction of internal and external factors. Efforts were made to determine the extent of global financial crisis on Russian gas industry. Master thesis also focuses on the question whether the Russian economy will be deepen on revenues from oil and natural gas export in 2020 more than at the beginning of 21st century. The aim of this thesis is to highlight the close link between economic and political interests of Russia in energy cooperation.
193

Zkapalněný zemní plyn / Liquefied natural gas

Borkovec, Ondřej January 2017 (has links)
This master thesis deals with issue of natural gas liquefaction, its transport, storing and regasification. Part of this work was designing off a small liquefaction cycle and regasification unit.
194

Understanding European Natural Gas Market Dynamics : An ARCH Analysis of the Relationship Between Natural Gas Prices and Imports

Ellersiek, Christoph, Gnerre, Nadia January 2023 (has links)
This thesis analyses the relationship between month-ahead natural gas prices and imports into Europe against the backdrop of the 2022 Russian gas curtailment and gas price spike. Employing an ARCH model, the analysis focuses on the consortium of five major European consumers of natural gas: Italy, Germany, the Netherlands, the United Kingdom, and France. To gain a comprehensive understanding of the factors influencing natural gas prices in the European market, we include key variables such as natural gas consumption, production, storage levels, oil prices and temperature. The study finds that the European natural gas market is sensitive to decreased imports which exert a positive effect on prices and volatility. Therefore, we can infer that the proposed market factors influence gas prices in Europe. This research provides insights into the dynamics of natural gas pricing, presenting the implications of disruptions and uncertainties in the contemporary natural gas market.
195

Auto-Ignition Characteristics of Hydrogen Enriched Natural Gas for Gas Turbine Applications

Loving, Christopher T 01 January 2023 (has links) (PDF)
A successful transition to clean energy hinges on meeting the world's growing energy demand while reducing greenhouse gas emissions. Achieving this will require significant growth in electricity generation from clean and carbon-free energy sources. Several energy providers have already begun the transition from traditional carbon-based fuels to cleaner alternatives, such as hydrogen and hydrogen enriched natural gas. However, there are still many technical challenges that must be addressed when applying these fuels in gas turbines. The application of hydrogen or hydrogen/natural gas blends to advanced class gas turbines, which have higher operating pressures and temperatures has raised concerns about the potential for leakages or fuel sequencing operations where flammable mixtures of fuel and air could auto-ignite. Public information on the auto-ignition of hydrogen in air at atmospheric pressure is well documented. Such data shows the auto-ignition temperature of hydrogen is roughly 100 °C lower than that of methane. Studies also show that as pressure increases, methane's auto-ignition temperature decreases. However, there was insufficient information in the published literature to characterize the influence of pressure on auto-ignition for hydrogen fuel applications. This study describes the test methodology used to evaluate conditions where auto-ignition occurs for various fuel-air mixtures operating at pressures between 1-30 atmospheres and equivalence ratios between 0.2-1.6. Testing was completed with hydrogen, natural gas and blends at various equivalence ratios using a heated volume with multiple reactant delivery methods. Testing was performed for natural gas to validate the test and data collection methods cited in prior published literature. Results indicate that at atmospheric pressures, an increase in hydrogen concentration results in a reduced auto-ignition temperature. However, at 30 atmospheres, the auto-ignition temperature increased with higher hydrogen concentrations. iv Variations of auto-ignition delay times were also observed during the testing and are compared to modeling predictions, providing insight into auto-ignition characteristics.
196

Development and evaluation of aromatic polyamide-imide membranes for H₂S and CO₂ separations from natural gas

Vaughn, Justin 15 March 2013 (has links)
Over the past decade, membrane based gas separations have gained traction in industry as an attractive alternative to traditional thermally based separations due to their potential to offer lower operational and capital expenditures, greater ease of operation and lower environmental impact. As membrane research evolves, new state-of-the-art membrane materials as well as processes utilizing membranes will likely be developed. Therefore, their incorporation into existing thermally based units as a debottlenecking step or as a stand-alone separation unit is expected to become increasingly more common. Specifically for natural gas, utilization of smaller, more remote natural gas wells will require the use of less equipment intensive and more flexible separation technologies, which precludes the use of traditional, more capital and equipment intensive thermally based units. The use of membranes is, however, not without challenges. Perhaps the most important hurdle to overcome in membrane development for natural gas purification is the ability to maintain high efficiency in the presence of harsh feed components such as CO₂ and H₂S, both of which can swell and plasticize polymer membranes. Additionally, as this project demonstrates, achievement of similarly high selectivity for both CO₂ and H₂S is challenged by the different governing factors that control their transport through polymeric membranes. However, as others have suggested and shown, as well as what is demonstrated in this project, when CO₂ is the primary contaminant of interest, maintaining high CO₂/CH₄ efficiency appears to be more important in relation to product loss in the downstream. This work focuses on a class of fluorinated, glassy polyamide-imides which show high plasticization resistance without the need for covalent crosslinking. Membranes formed from various polyamide-imide materials show high mixed gas selectivities with adequate productivities when subjected to feed conditions that more closely resemble those that may be encountered in a real natural gas well. The results of this project highlight the polyamide-imide family as a promising platform for future membrane material development for materials aimed at aggressive natural gas purifications due to their ability to maintain high selectivities under aggressive feed conditions without the need for extensive stabilization methods.
197

An optimization program to minimize the cost of natural gas

Yaege, Margaret Ann. January 1984 (has links)
Call number: LD2668 .T4 1984 Y33 / Master of Science
198

Price interdependence in Northwest European natural gas markets

Koenig, Philipp January 2014 (has links)
No description available.
199

The potential for using energy from flared gas or renewable resources for on-site hydraulic fracturing wastewater treatment

Glazer, Yael Rebecca 18 September 2014 (has links)
The oil and gas well completion method of hydraulic fracturing faces several environmental challenges: the process is highly water-intensive; it generates a significant volume of wastewater; and it is associated with widespread flaring of co-produced natural gas. One possible solution to simultaneously mitigate these challenges is to use the energy from flared natural gas to power on-site wastewater treatment, thereby reducing 1) flared gas without application, 2) the volumes of wastewater, and 3) the volumes of freshwater that need to be procured for subsequent shale production, as the treated wastewater could be reused. In regions with minimal flaring a potential solution is to couple renewable electricity (generated from solar and wind energy) with on-site wastewater treatment, thereby 1) reducing the volumes of wastewater, 2) reducing the volumes of freshwater that need to be procured for subsequent shale production, and 3) displacing fossil fuel energy for treatment. This study builds an analytical framework for assessing the technical potential of these approaches. In this research, the hydraulic fracturing wastewater characteristics (such as quality, quantity, and flow rates) were considered along with various treatment technologies best suited to utilizing natural gas and renewable electricity, using the Permian Basin in west Texas as a geographic test bed for analysis. For the analysis looking at using flared natural gas energy for on-site treatment, the required volume of gas to meet the thermal energy requirements for treatment was calculated on a per-well basis. Additionally, the volume of product water (defined here as the treated water that can be reused) based on the technology type was determined. Finally, the theoretical maximum volume of product water that could be generated using the total volume of natural gas that was flared in Texas in 2012 as a benchmark was calculated. It was concluded that the thermal energy required to treat wastewater that returns to the surface over the first ten days after a well is completed is 140–820 Million British Thermal Units (MMBTU) and would generate 750–6,800 cubic meters of product water depending on the treatment technology. Additionally, based on the thermal technologies assessed in this study, the theoretical maximum volume of product water that can be generated statewide using the energy from the flared gas in 2012 is 180–540 million cubic meters, representing approximately 3–9% of the state’s annual water demand for municipal purposes or 1–2.4% of total statewide water demand for all purposes. This is enough gas to treat more water than was projected would be used for the entire mining sector in 2010 in Texas. For the analysis coupling renewable electricity with on-site treatment, the necessary energy for water management upstream and downstream of a well site was calculated and compared with the current energy requirements and those of a proposed strategy where a portion of the wastewater is treated on-site and reused on a subsequent well. Through this analysis, it was determined that implementing on-site treatment using renewable electricity could reduce freshwater requirements by 11–26%. Finally, it was calculated that this approach could displace approximately 16% of the fossil fuel energy requirements for pumping freshwater, trucking that water to the well site, and trucking wastewater to a disposal well. / text
200

The drill down

Friel, Katherine Dailey 14 October 2014 (has links)
The town of Millerton, Pa., has always been a small, rural farming community. Settled atop of the famed Marcellus Shale in the foothills of the Appalachians, there have always been rumors of natural gas in the hills around town. In 2008, natural gas companies arrived and began drilling. For a select few lucky enough to have property around the gas wells, their arrival means big money. But not all residents will get so lucky. For many folks in Millerton, the arrival of the gas companies means more traffic, more pollution, more crime and more inconvenience without a monthly royalty check to buffer the pain. The sheer amount of natural gas scientists predict is in the Marcellus Shale will forever change how the U.S. and the rest of the world use energy. Politicians tout it as liberation from foreign oil. Scientists see it as an alternative to “dirty” coal. For this small town, natural gas means change. The money the natural gas companies are pumping into this local economy will change the lives of the townsfolk- and the town itself- forever. / text

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