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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.
181

A baseline assessment of local mercury deposition from coal-fired power plants in Central Texas

Furl, Chad Van. Lehr, Larry L. Van Walsum, G. Peter White, Joseph Daniel. January 2006 (has links)
Thesis (M.E.S.)--Baylor University, 2006. / Includes bibliographical references (p. 101-106).
182

Electronic instrumentation of coal slurry impoundments for real-time data collection to support automated monitoring

Altobello, James A. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains x, 162 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 160-162).
183

Removal of trace elements from coal using a multiple-property processing circuit /

Hill, David T., January 1994 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 75-77). Also available via the Internet.
184

The effects of the reunification of the German Democratic Republic and the Federal Republic of Germany on the South African coal export market

Von Ketelhodt, Alison Freifrau 22 August 2012 (has links)
M.Phil. / The following study will examine the effects of the reunification of East Germany and West Germany on the South African coal exports to Germany. The Berlin Wall fell on 9 November 1989, and thereafter the reunification of East and West Germany took one year to complete. Before the reunification (1981 to 1988), the West German economy was booming, and the contributions of the different energy carriers to the West German energy consumption were as follows: Contribution in 19811 (%) Contribution in 1988 (%) Hard Coal! 20,9 19,1 Brown Coal 10,6 8,1 Oil 44,8 41,9 Gas 16,0 16,2 Nuclear 4,7 12,0 Other Energies 2,9 2,5 As West Germany is a country which is poor in indigenous energy resources, the majority of the above energies were and still are imported. Before reunification, West Germany had, however an established local hard coal mining industry. Due to rising expenses, however, the mining industry was being cut back. Production had decreased as had the number of people employed by the industry. The main consumers of hard coal were the electricity generation industry and production industries other than the iron and steel industry. To supplement hard coal supply, steam coal was being imported into West Germany. The countries of origin for these imports were South Africa, Poland, the USA, Australia, Canada, and more recently, Indonesia and Colombia. By contrast, the comparable energy picture for East Germany from 1981 to 1988 was as follows: Contribution in 1981 (%) Contribution in 1988 (%) Hard Coal 5,0 4,5 Brown Coal 64,4 68,5 Oil 16,5 13,2 Gas 9,2 9,3 Nuclear 4,0 3,7 Other Energies 0,8 0,5 The majority of the above energy was imported, but all the brown coal required was mined locally. Hard coal, which was required mainly for the iron and steel industry, was imported chiefly from Poland. The East German economy was close to bankruptcy shortly before the reunification. The extent of this condition, however, only became apparent after the reunification. The poor condition of the industries and their detrimental effect on the environment came as a shock to all. The initial step taken after the reunification, was to close all the East German nuclear power stations, mainly for safety reasons. Thereafter, large portions of the brown coal mining industry, along with many other sectors of the industry were closed while others were reconstructed. The enormous economic strength of West Germany was demonstrated in the speed with which the East was converted to a market economy. Effects of the reunification were also seen in the energy sector
185

Die toepassing van eksplorasiefase geologiese inligting op mynboubeplanning in die Noordelike Secundasteenkoolveld

Du Toit, Jan Smuts 12 November 2012 (has links)
M.Sc.
186

A Characterization and Determination of the Coal Reserves and Resources of Southwest Virginia

Westman, Erik C. 27 April 1999 (has links)
Coal mining and timber are the two primary industries supporting the people of Southwest Virginia. Coal mining has occurred for more than 100 years, but production has dropped since reaching a peak in 1990. In order to properly plan with remaining coal production a study was conducted to characterize and estimate coal resources. Seam thickness was found to be the parameter which most influenced resource levels. An economic model was developed to determine which portion of the reserves could economically be extracted. It was found that 3.95 billion tons, or 14% of the remaining resource, is economic under current mining conditions. More than 60% of these reserves, however, are in deep seams which require shafts to be constructed prior to initiation of mining. / Ph. D.
187

Rapid pyrolysis and hydropyrolysis of coal

Suuberg, Eric Michael January 1978 (has links)
Thesis. 1978. Sc.D.--Massachusetts Institute of Technology. Dept. of Chemical Engineering. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Bibliography: leaves 382-396. / by Eric M. Suuberg. / Sc.D.
188

Mercury speciation in air from coal fired power stations

Jongwana, Lulamile Theo 22 July 2014 (has links)
Mercury occurs naturally and as a result of human activities. One such activity is the combustion of mineral-enriched, sub-bituminous coal to produce electricityan industry that has existed for over 100 years. Although coal is absolutely necessary to supply the power that South Africa and its neighbouring countries requires, the emitted gases, especially mercury, impact the environment and present a complex array of health-related problems. Controlling the impact of mercury present in the environment depends on the efforts of governments, scientists, business and industry, agriculture, environmental organizations and individuals. Mercury is emitted from the point sources in different forms. Accurate determination of the emitted forms or species of mercury has become a global interest. Determination of the various mercury species requires several well-understood analytical techniques for the confident assessment of potentially contaminated samples. This study focuses on the development, validation and application of analytical methodologies that are capable of differentiating between the different forms of mercury in environmental samples (air, liquids and solids) from coal-fired power plants. Capillary electrophoresis with amperometric detection, high performance liquid chromatography with amperometric detection, and atomic fluorescence spectrometry methods were developed for mercury speciation. Very low detection limits observed using the methods. For capillary electrophoresis with amperometric detection, the detection limits were 0.005±0.002 μg/l for Hg2+ and 0.4±0.05 μg/l for MeHg+. Detection limits of 2±0.04 ppt and 0.01±0.02 μg/l for Hg2+ were observed for high performance liquid chromatography with amperometric detection and atomic fluorescence spectrometry respectively. These detection limits are attractive for the monitoring of mercury in the environment. Total mercury in solids (coal and ash) was measured by direct mercury measurement using a well-established method, involving the use of the mercury analyzer LECO AMA-254. Total gaseous mercury was measured using the Tekran 2537B system. On application to environmental samples, very good correlations in results were observed between the different methods. Mercury speciation in South African coal after acid extraction showed that only Hg2+ species was detected from the extracts and that 96% of total Hg in acid extracts is in the Hg2+ species form. Different trends in Hg speciation results at the Elandsfontein Air Quality Monitoring (AQM) station were observed over the sampling period. During winter sampling, Hg2+ was the predominant species, while Hg0 was predominant the species during summer sampling. Mercury speciation carried out at Duvha Power Station (units 1 and 2), equipped with fabric filter devices, revealed that the predominant form of Hg after the fabric filter devices was Hg2+, due to oxidation of Hg0 to Hg2+ as the flue gas temperature decreases. Mercury speciation at the Majuba Underground Coal Gasification flare revealed that although mercury is emitted from power plants in the form of different chemical species, with each species have a different fate in the atmosphere, the climate, wind direction and terrain also play roles in the transport of mercury emissions. Therefore, it is difficult to predict the transport patterns of emissions. Nonetheless, with correct measuring equipment and modelling, the patterns of emissions should be able to be predicted. The patterns observed and data recorded at the Elandsfontein AQM station and Duvha Power Station, respectively, were however, insufficient to permit accurate modelling. This study raised a number of other questions which are too comprehensive for this study to address. Therefore, more comprehensive atmospheric and combustion studies should be done.
189

Non-Destructive Solubilization of Coal Using Ultrasonic Energy

Gaikwad, Rajendra P. January 1985 (has links)
Note:
190

Low Temperature Drying of Ultrafine Coal

Freeland, Chad Lee 18 January 2012 (has links)
A new dewatering technology, called low temperature drying, has been developed to remove water from ultrafine (minus 325 mesh) coal particles. The process subjects partially dewatered solids to intense mechanical shearing in the presence of unsaturated air. Theoretical analysis of the thermodynamic properties of water indicates residual surface moisture should spontaneously evaporate under these conditions. This is contingent on the large surface area of these fine particles being adequately exposed to an unsaturated stream of air. To demonstrate this process, three dispersion methods were selected for bench-scale testing; the static breaker, air jet conveyor, and centrifugal fan. Each of these devices was chosen for its ability to fully disperse and pneumatically convey the feed cake. The moisture content of the feed cake, and the temperature and relative humidity of the process air were the key parameters that most significantly affected dryer performance. Of the three methods tested, the centrifugal fan produced the best results. The fan was capable of handling feeds as wet as 21.5% and consistently dried the coal fines below 2% moisture. The cost of the air and heat required to provide good drying performance was modeled to explore the practicality of the drying process. Modeling was accomplished by modifying equations developed for thermal dryers. The modeling results indicate, if good exposure of the fine particle surface area is achieved, dryers operating with either heated or unheated (ambient) air can be used for drying ultrafine coal. / Master of Science

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