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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.
1

Investigation into gas flaring reduction in the oil and gas industry

Abuhesa, Musa Bashir January 2010 (has links)
Gas flaring is the burning of unwanted produced natural gas, which cannot be processed or sold during oil and gas production and processing operations. In past decades, gas flaring was believed to be environmentally tolerable. However, scientists have found that the flaring of gas is an impediment to the environment; this has led to attempting to tackle the problem of gas flaring to advance it to an acceptable level worldwide. In this study, two options were investigated for the utilisation of natural gas that was previously flared. The first option was a theoretical investigation of the use of ceramic perovskite membranes in a tubular reactor for the partial oxidation of methane (flare gas) to syngas. The H2/C product ratio of partial oxidation of methane is 2:1, which is suitable for Fischer-Tropch technology or methanol synthesis. It was found that this option is ideal for converting natural gas into synthesis gas (CO + H2), and it reduces capital and running costs, as these membranes are able to separate oxygen from the air stream with no need for an oxygen separation plant. The novelty of this approach is that the production of syngas using oxygen selective membranes can be achieved at the “Wellhead” with no requirement for the gas to be transported and a consequent reduction in transport costs. The second option was an experimental investigation in using spraying and atomisation techniques for the generation of carbon nanotubes, by spraying simulated catalyst solution droplets into a hydrocarbon gas stream (methane as a carbon source) using a novel “atomiser device” incorporating pressure swirl atomisers. The second part of the investigation was divided into two phases: Phase-I, which was implemented at the Spray Research Group laboratory at the University of Salford, involved a series of experiments which were undertaken to produce fine aerosol droplets that have a number mean diameter of less than or equal to 5 μm, which was successfully achieved. In this phase, water and air were used to simulate the metal catalyst and methane, respectively, which were used in Phase-II. Phase-II trials were implemented at the University of Oxford on a collaborative basis. A furnace was installed underneath of the Phase-I “atomiser device” and the stream of droplet particles fell down through the furnace (400 - 800o C). Reaction inside the furnace occurred to produce the Single Wall Carbon Nanotubes (SWCNT) material. The preliminary results of the experiments in this Phase showed that it is possible to produce SWCNT. This investigation also considered an economic analysis of reducing gas flaring. A Visual Basic (VB) programme was developed to make a cost comparison between the proposed options and current conventional plants. The consideration of the economic analysis demonstrated that the cost of natural gas flaring exceeds those for syngas and Single-Walled Carbon Nanotubes production.
2

Coal-fired Power Plants with Flexible Amine-based CCS and Co-located Wind Power: Environmental, Economic and Reliability Outcomes

Bandyopadhyay, Rubenka Bandyopadhyay January 2016 (has links)
<p>Carbon Capture and Storage (CCS) technologies provide a means to significantly reduce carbon emissions from the existing fleet of fossil-fired plants, and hence can facilitate a gradual transition from conventional to more sustainable sources of electric power. This is especially relevant for coal plants that have a CO2 emission rate that is roughly two times higher than that of natural gas plants. Of the different kinds of CCS technology available, post-combustion amine based CCS is the best developed and hence more suitable for retrofitting an existing coal plant. The high costs from operating CCS could be reduced by enabling flexible operation through amine storage or allowing partial capture of CO2 during high electricity prices. This flexibility is also found to improve the power plant’s ramp capability, enabling it to offset the intermittency of renewable power sources. This thesis proposes a solution to problems associated with two promising technologies for decarbonizing the electric power system: the high costs of the energy penalty of CCS, and the intermittency and non-dispatchability of wind power. It explores the economic and technical feasibility of a hybrid system consisting of a coal plant retrofitted with a post-combustion-amine based CCS system equipped with the option to perform partial capture or amine storage, and a co-located wind farm. A techno-economic assessment of the performance of the hybrid system is carried out both from the perspective of the stakeholders (utility owners, investors, etc.) as well as that of the power system operator. </p><p>In order to perform the assessment from the perspective of the facility owners (e.g., electric power utilities, independent power producers), an optimal design and operating strategy of the hybrid system is determined for both the amine storage and partial capture configurations. A linear optimization model is developed to determine the optimal component sizes for the hybrid system and capture rates while meeting constraints on annual average emission targets of CO2, and variability of the combined power output. Results indicate that there are economic benefits of flexible operation relative to conventional CCS, and demonstrate that the hybrid system could operate as an energy storage system: providing an effective pathway for wind power integration as well as a mechanism to mute the variability of intermittent wind power. </p><p>In order to assess the performance of the hybrid system from the perspective of the system operator, a modified Unit Commitment/ Economic Dispatch model is built to consider and represent the techno-economic aspects of operation of the hybrid system within a power grid. The hybrid system is found to be effective in helping the power system meet an average CO2 emissions limit equivalent to the CO2 emission rate of a state-of-the-art natural gas plant, and to reduce power system operation costs and number of instances and magnitude of energy and reserve scarcity.</p> / Dissertation
3

Development of a Technology Transfer Score for Evaluating Research Proposals| Case Study of Demand Response Technologies in the Pacific Northwest

Estep, Judith 07 April 2017 (has links)
<p> Investment in Research and Development (R&amp;D) is necessary for innovation, allowing an organization to maintain a competitive edge. The U.S. Federal Government invests billions of dollars, primarily in basic research technologies to help fill the pipeline for other organizations to take the technology into commercialization. However, it is not about just investing in innovation, it is about converting that research into application. A cursory review of the research proposal evaluation criteria suggests that there is little to no emphasis placed on the transfer of research results. This effort is motivated by a need to move research into application. </p><p> One segment that is facing technology challenges is the energy sector. Historically, the electric grid has been stable and predictable; therefore, there were no immediate drivers to innovate. However, an aging infrastructure, integration of renewable energy, and aggressive energy efficiency targets are motivating the need for research and to put promising results into application. Many technologies exist or are in development but the rate at which they are being adopted is slow. </p><p> The goal of this research is to develop a decision model that can be used to identify the technology transfer potential of a research proposal. An organization can use the model to select the proposals whose research outcomes are more likely to move into application. The model begins to close the chasm between research and application&mdash;otherwise known as the &ldquo;valley of death&rdquo;. </p><p> A comprehensive literature review was conducted to understand when the idea of technology application or transfer should begin. Next, the attributes that are necessary for successful technology transfer were identified. The emphasis of successful technology transfer occurs when there is a productive relationship between the researchers and the technology recipient. A hierarchical decision model, along with desirability curves, was used to understand the complexities of the researcher and recipient relationship, specific to technology transfer. In this research, the evaluation criteria of several research organizations were assessed to understand the extent to which the success attributes that were identified in literature were considered when reviewing research proposals. While some of the organizations included a few of the success attributes, none of the organizations considered all of the attributes. In addition, none of the organizations quantified the value of the success attributes. </p><p> The effectiveness of the model relies extensively on expert judgments to complete the model validation and quantification. Subject matter experts ranging from senior executives with extensive experience in technology transfer to principal research investigators from national labs, universities, utilities, and non-profit research organizations were used to ensure a comprehensive and cross-functional validation and quantification of the decision model. </p><p> The quantified model was validated using a case study involving demand response (DR) technology proposals in the Pacific Northwest. The DR technologies were selected based on their potential to solve some of the region&rsquo;s most prevalent issues. In addition, several sensitivity scenarios were developed to test the model&rsquo;s response to extreme case scenarios, impact of perturbations in expert responses, and if it can be applied to other than demand response technologies. In other words, is the model technology agnostic? In addition, the flexibility of the model to be used as a tool for communicating which success attributes in a research proposal are deficient and need strengthening and how improvements would increase the overall technology transfer score were assessed. The low scoring success attributes in the case study proposals (e.g. project meetings, etc.) were clearly identified as the areas to be improved for increasing the technology transfer score. As a communication tool, the model could help a research organization identify areas they could bolster to improve their overall technology transfer score. Similarly, the technology recipient could use the results to identify areas that need to be reinforced, as the research is ongoing. </p><p> The research objective is to develop a decision model resulting in a technology transfer score that can be used to assess the technology transfer potential of a research proposal. The technology transfer score can be used by an organization in the development of a research portfolio. An organization&rsquo;s growth, in a highly competitive global market, hinges on superior R&amp;D performance and the ability to apply the results. The energy sector is no different. While there is sufficient research being done to address the issues facing the utility industry, the rate at which technologies are adopted is lagging. The technology transfer score has the potential to increase the success of crossing the chasm to successful application by helping an organization make informed and deliberate decisions about their research portfolio.</p>
4

A THEORETICAL AND NUMERICAL INVESTIGATION OF LAMINAR BOUNDARY-LAYER HEAT AND MASS TRANSFER IN NATURAL CONVECTION: I. SIMULTANEOUS HEAT AND MASS TRANSFER. II. MASS TRANSFER IN THE ABSENCE OF HEAT TRANSFER

CARDNER, DAVID VICTOR January 1963 (has links)
No description available.
5

AN EXPERIMENTAL INVESTIGATION OF HEAT TRANSFER AND DRAG FOR A FLAT PLATE IN A HIGH ENERGY, RAREFIED FLOW AT HIGH MACH NUMBER

PETERMAN, DAVID ALLEN, SR. January 1964 (has links)
No description available.
6

THE HEAT TRANSFER RESPONSE OF A HOT-WIRE ANEMOMETER

STRICKLAND, WILLIAM THOMAS, JR. January 1964 (has links)
No description available.
7

THERMAL ANALYSIS OF SPACE RADIATORS

RUSSELL, LYNN DARNELL January 1966 (has links)
No description available.
8

ANALYSIS OF THREE FLUID, CROSS FLOW HEAT EXCHANGERS

WILLIS, NOEL CHARLES, JR. January 1966 (has links)
No description available.
9

STEADY-STATE THERMAL DESIGN OF SPACE RADIATORS

LOPEZ, LOUIS January 1967 (has links)
No description available.
10

THE APPLICATION OF RADIO FREQUENCY ELECTROMAGNETIC FIELDS TO HEAT AND CONTROL THE STATE OF A FLOWING PLASMA

VERMEULEN, PETER JAMES January 1967 (has links)
No description available.

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