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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

Evaluation of biodiesel from used cooking sunflower oil as substitute fuel.

Steyn, Christoffel Bernadus. January 2010 (has links)
Thesis (MTech. degree in Mechanical Engineering)--Tshwane University of Technology, 2010. / This study evaluates the use of biodiesel as an alternative fuel for diesel engines. The fuel properties, performance, emission characteristics and combustion characteristics of a four-stroke, four-cylinder water cooled, high speed direct injection (DI) diesel engine operated on biodiesel, 30% biodiesel and 70% biodiesel blended fuels were measured. Results related to the direct use of biodiesel as a diesel engine fuel indicate that this is possible but not preferable because of its high viscosity and cetane number. Biodiesel could be used in the blends with diesel fuel, because most of the measured properties of the biodiesel-diesel blended fuels were close to those of the diesel fuel. It was found that the performance parameters of the biodiesel-diesel blended fuels did not differ greatly from those of diesel fuel. A slight power decrease, with an increase in brake specific fuel consumption (BSFC), was noticed with the blend fuels. Smoke emissions were reduced for the blends while NOx was increased remarkably for the biodiesel-blended fuels. The test results demonstrated that the combustion carbon deposits (CCD) of biodiesel are a little less than that of the diesel fuel. The peak combustion pressure of the B70 blended fuel was found to be the highest amongst the four tested fuels. It is consequently argued that biodiesel appears to offer a potential alternative "greener" energy substitute for fossil fuel.
2

Particle size, gas temperature, and impingement cooling effects on high pressure turbine deposition in land based gas turbines from various synfuels /

Crosby, Jared M., January 2007 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Mechanical Engineering, 2007. / Some pages inverted or out of order. Includes bibliographical references (p. 83-86).
3

Production and high temperature treatment of syngas /

Botha, Martin Francis. January 2010 (has links)
Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2010. / Full text also available online. Scroll down for electronic link.
4

'n Totale kostevergelyking tussen verskeie sintetiese brandstofvervaardigingsprosesse en konvensionele ru-olie : 'n tegno-ekonomiese studie

18 March 2014 (has links)
M.Phil. (Energy Studies) / Liquid fuels provide in a large percentage of South Africa's energy requirements. Because of the vastness of the country no other means of propelling transport could take the place of liquid fuel. South Africa who has for a substantial period found herself being officially cut-off from international crude oil (embargo) and other commodities such as capital, had up to ± 1991 survive this onslaught. Alternatives for the substitution of crude oil derived products (mostly liquid fuels) has been under investigation for many years, internationally as well as locally~ Because of the recent change in the situation, the approach to new investment in this field will now only be effected should it be economically more attractive than investment in the traditional crude oil processes. This study was specifically aimed at, from a South African viewpoint, summarizing various applicable liquid fuel manufacturing processes and related raw material resources, and comparing these processes both from an economic and technological angle with that of crude oil refining. The following resources were investigated: Coal, torbanite, sugar (from sugar cane), natural gas and sunflower seeds. Processes such as coal to fuels (Fischer-Tropsch, coal hydrogenation, solvent extraction), metanol to fuels (MTG-process), metanol ex natural gas (Mobil-M), methanol ex coal, ethanol ex sugar, natural gas to fuels (Fischer-Tropsch, Shell-SMOS), esters (diesel) ex sunflower seeds, fuels ex torbanite via retorting were researched. Aspects covering the availability of resources, degree of commercialisation of processes, product quality and fuel/engine compatibility and general economic and technological guidelines were covered in the study.
5

Process evaluation of underground coal gasification: an exergy analysis

Moodley, Keeshan January 2016 (has links)
A dissertation submitted to the Faculty of Engineering and the Built Environment, University of Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering Johannesburg, 29 August 2016 / This study discusses underground coal gasification (UCG) and the analysis thereof. Two main methods were used. The first is the Bond Equivalent Diagram, which gives an ideal of where operations should take place in relation to their coal and product gas compositions. This method was used to analyze several real life sites for their idealized and actual operations. The second consisted of a comparative exergy simulation study. This was done for an air-blown UCG plant with a downstream Fischer-Tropsch reactor and an oxygen-blown UCG plant with upstream air separation. The plants were analyzed by their overall exergy efficiency as well as their exergy outputs with respect to coal inputs (fuel). It was discovered that the air-blown simulation with downstream Fischer-Tropsch was the better choice from an exergy point of view due to it having higher efficiencies (1.5 for overall, 1.38 for fuel) as opposed to the oxygen-blown simulation (0.77 overall, 0.8 for fuel). This coupled with other design and safety factors led to the conclusion that the air-blown simulation was better. / MT2017
6

A financial analysis of synthetic fuel technologies.

Majd, Saman January 1979 (has links)
Thesis. 1979. M.S.--Massachusetts Institute of Technology. Alfred P. Sloan School of Management. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND DEWEY. / Includes bibliographical references. / M.S.
7

United States synthetic fuels corporation : its rise and demise

Priddy, Hervey Amsler 06 November 2013 (has links)
The energy crisis during the presidency of Jimmy Carter stimulated several major pieces of legislation that together produced the Department of Energy (DOE), the National Energy Plan (NEP), the windfall profits tax, and the Energy Security Act of 1980 (ESA). This dissertation focuses on the Energy Security Act, which was signed into law on June 30, 1980, and created the congressionally chartered United States Synthetic Fuels Corporation (SFC), one of the initial efforts to provide the United States energy security. John Sawhill, nominated by Carter as the first SFC chair, was responsible for managing the corporation along with six other directors. The Senate confirmed none of these seven individuals. This inaction forced Carter to make recess appointments of Sawhill and four others to the SFC board. With the election of former California governor Ronald Reagan as president in November 1980, emphasis on the SFC and financial assistance for development of a domestic synthetic fuels industry diminished -- so much so that the corporation closed its doors in April 1986. The SFC funded four synthetic fuels projects. None survive today. During its life, Synfuels Corporation spent approximately $960 million. Congress authorized funding of $88 billion plus $35 million in annual administrative expenses (adjusted for inflation) for the SFC, with a maximum of three hundred full-time professional employees, over its legislated twelve-year existence. The mandated goal was the production of at least five hundred thousand barrels of crude oil equivalent per day of synthetic fuels from domestic sources by 1987 and at least two million per day by 1992. The SFC was legislatively chartered to be free of normal government rules, regulations, and procedures. Carter did not want the synthetic fuels effort to be housed within the Department of Energy. He knew that to meet the goals of the act, any entity must be able to move with speed and be permitted to pay above government-level salaries. Reagan, who did not like the SFC or its mandate, preferred the free market with little or no government interference. Congress simply could not leave the SFC alone, however. So instead of a seven-member board of directors, the SFC ended up with a board of 542 -- counting members of Congress. This dissertation provides an in-depth look at the SFC, Carter's solution to the energy crisis as presented in his July 15, 1979 address to the nation on energy and national goals, commonly referred to as "The Malaise Speech." This talk from the Oval Office, was unique, and remains today the most unusual presidential address in the nation's history. Historians have written and analyzed the first half, a sermon emphasizing all that was wrong with America, but few writers have done the same for second half of the speech, which is the subject of this paper. In the latter part of his speech, Carter emphasized his solution to the country's malaise: solving America's energy shortage, to be accomplished by what he termed an "energy security corporation." Only two authors have examined the SFC. Sabrina Willis penned a 1987 essay titled "The Synthetic Fuels Corporation as an Organizational Failure in Policy Mobilization," which appeared in The Unfilled Promise of Synthetic Fuels, edited by Ernest J. Yanarella and William Green. She argued that SFC problems were "so many and so serious that it is difficult to determine exactly why the corporation failed to come [even] close to achieving the goals set for it by Congress . . . ." Willis was particularly critical of Ed Noble, appointed as chair of the board of directors by Reagan, when she wrote, "his [Noble] managerial style was too weak to effectively guide a controversial organization." Willis did not have access to the SFC papers, staff or members of the board of directors. Furthermore, she did not research or make use of the plethora of published congressional hearings. Although her examination was superficial, it was definitely pointed. In 2011, Ralph L. Bayrer, former SFC vice president of projects, published his account, The Saga of the U.S. Synthetic Fuels Corporation: A Cautionary Tale. Bayrer, an engineer by education and profession, addressed primarily the engineering aspects of the SFC projects. He presented a favorable assessment of Noble and his leadership. Noble, in Bayrer's opinion, "had a clear view of what he [Noble] wanted to achieve at the SFC," and several "accomplishments" while chair of the Synthetic Fuels Corporation. Bayrer dedicated his book to Noble, noting the SFC "came to a premature end," and had David Stockman, Reagan's director of the Office of Management and Budget not intervened, Noble would have been almost successful in his strategic vision. Bayrer, however, did not interview former employees, former board members, or congressional leaders and their staffs. He relied instead on congressional hearings and his own papers. Because Bayrer worked for the SFC from its beginning to the end, the viewpoints in his publication are thus clouded by personal involvement. He did provide invaluable assistance to the author though, answering questions about the projects and providing needed documents, for which the author is most grateful. Yet, after considerable research and numerous interviews, the author does not agree with Bayrer's assessment of the SFC. The United States Synthetic Fuels Corporation was a superb idea. Its objective was a bold step by a president to address America's addiction to imported crude oil, which had made the nation vulnerable to the vagaries of an unstable region of the world. Unfortunately, a vacuum of presidential leadership, congressional meddling, and embarrassingly poor management cursed the SFC from its very creation. Almost a full year -- 351 days -- passed from the date Carter offered the concept of the SFC to the nation until its enactment into law. Moreover, Carter's distraction with a possible primary opponent, Sen. Edward Kennedy (D-MA), whom he disliked intensely, hampered the president's ability to remain focused on the issue, as well as his view of the presidency as a trusteeship, above politics. After the election of Ronald Reagan to the presidency, all interest in supporting synthetic fuels evaporated. The SFC became merely a place to repay political donors and friends -- and minor ones at that. By thoroughly examining the rise and demise of the United States Synthetic Fuels Corporation, historians will be able to see prima facie evidence of the importance of commitment, persistence, and leadership -- both presidentially and managerially -- and how it is possible for a government entity to vanish into the dust bin of history. And, we will be able to answer the questions: what was the SFC, what did it accomplish, what happened to it, and why? / text
8

A possible solution for the U.S. Navy's addiction to petroleum : a business case analysis for transitioning the U. S. Navy from petroleum to synthetic fuel resources /

Benedetto, Michael V. January 2007 (has links) (PDF)
Thesis (M.S. in Operations Research)--Naval Postgraduate School, March 2007. / Thesis Advisor(s): Daniel A. Nussbaum. "March 2007." Reproduced by NTIS - ADA467107 Includes bibliographical references (p. 95-99).
9

The oligomerization of propene over nickel synthetic mica-montmorillonite

Jacobs, Lester Lance January 1987 (has links)
Bibliography: pages 150-156. / The catalytic oligomerization of propene to liquid fuels using synthetic mica montmorillonite (SMM) as well as the effect of incorporating nickel into the lattice and nickel, cobalt and zinc into the interlayer spaces was investigated. NiSMM is more active for propene oligomerization than SMM, although the product selectivity (60% of the oligomers boiled at above 453 K) is similar. The increase in activity of NiSMM is attributed to an increase in the surface acidity of the catalyst. The maximum activity over the nickel exchanged catalyst occurs at a nickel loading of 0.057 wt %. It is proposed that the bond strength of the acidic hydroxyl groups are perturbed by the polarizing effect of the divalent cation (Co, Zn or Ni) present in the interlayer spaces of SMM. The reduction of nickel, ion exchanged into SMM, removes the induction period associated with SMM and increases the catalyst lifetime. However, reduction of the lattice nickel results in a decrease in catalyst lifetime although the Bronsted acidity has increased. It is proposed that the metallic nickel present in reduced NiSMM may promote dehydrogenation of high molecular weight hydrocarbons thus causing rapid deactivation of the catalyst by increasing the formation of "graphitic" coke. The lifetime of NiSMM is greatly reduced by using a wet propene feed and reacting at higher temperatures (443 K) due to the generation of Bronsted sites and increased coke formation rates, respectively. Deactivation of the catalyst is associated with a "graphitic" coke build up. The RON of the petrol fraction is 94.5 and the hydrogenated diesel fraction has a cetane number less than 35.
10

Assessing the Economic Feasibility of Synthetic Natural Gas Under Conditions of Uncertainty

Iranmanesh, Mohammad M. 01 October 1981 (has links) (PDF)
The science of synthetic fuel production began in the seventeenth century. However, large-scale production of synthetic fuels started in the early 1900's and, for several decades, gas manufactured from coal significantly contributed to the U.S. economy. The production of synthetic fuels declined due to increases in the price of coal and discoveries of predominantly methane natural gas. Today, an extensive network of pipelines is used to transmit and distribute natural gas for industrial and residential applications. The decline of natural gas reserves in the United States, in conjunction with the availability of very large coal reserves, has provided the incentive for development of coal gasification plants. Synthetic fuels are expected to contribute significantly to the supply of energy before the end of this century, and coal will be the primary source for production of these fuels. By many accounts, difficulties in raising the high amount of initial capital and future uncertainties with regard to fuel and operating costs have made development of synthetic fuels economically infeasible. However, as the prices of oil and natural gas increase, synthetic fuels production becomes a more attractive alternative. The purpose of this study is to evaluate the economics of synthetic natural gas with the current state of technology and to determine its future role as prices of oil and gas increase. In this report, a general methodology of production of synthetic natural gas is explained. For the economic analysis, the Lurgi Model was selected because it has been the most common model used for commercial production of high BTU gases. An extensive analytical model is described in which inflated capital, fuel, and operating and maintenance costs were accounted for and the equivalent annual cost of cash flows over the project life was calculated. The risk analysis was accomplished by applying Monte Carlo techniques through a simulation model which handles risks associated with various input parameters. SLAM, a FORTRAN-based language, was selected as the simulation language. Based on the results, all the cost elements were evaluated and the sensitivity of the total cost to each element was examined. This study was extended to the calculation of costs associated with he generation of electricity by burning synthetic natural gas. The results were then compared to the respective costs related to oil-burning power plants. The results show that high cost of synthetic high BTU gas makes it difficult to compete with natural gas at current prices. Coal feed stocks represent a major portion of the total cost of synthetic gases. The cost of capital, which is a critical factor at the developing stage, constitutes a relatively small portion of the total cost over the plant life. A similar observation was made for operating and maintenance costs. However, the future regulations regarding pollution control could have a strong impact on this portion of the cost. For power generations, oil was found to be far more economical than using synthetic natural gas. The computer simulation also revealed that the total cost of each alternative is very sensitive to this fuel cost. The conclusion of this study points to the fuel costs as the dominant factor in the choice of fuel alternatives in the future.

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