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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

The dissolution and swelling of bituminous coal in n-methyl-pyrrolidone

Stoffa, Joseph M. January 2006 (has links)
Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains viii, 100 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 86-88).
2

Bituminous coal mining in Northern Missouri

Blake, True Walter. January 1914 (has links) (PDF)
Thesis--University of Missouri, School of Mines and Metallurgy, 1914. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed April 7, 2009)
3

Development of coker feeds from aromatic oil and bituminous coal digests

Clendenin, L. Mitchell. January 2004 (has links)
Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains ix, 193 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 150-156).
4

Instrumental neutron activation analysis of coal and coal fly ash

Higginbotham, Jack F January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
5

Fate of coal nitrogen

Pohl, John Henning January 1976 (has links)
Thesis. 1976. Sc.D.--Massachusetts Institute of Technology. Dept. of Chemical Engineering. / Microfiche copy available in Archives and Science. Incorrect foliation: leaves 204-219 are bound between leaves 238 and 239. / Vita. / Bibliography: leaves 385-427. / by John H. Pohl. / Sc.D.
6

Mineral matter effects in coal pyrolysis and hydropyroysis

Franklin, Howard D January 1980 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Bibliography: leaves 294-308. / by Howard D. Franklin. / Ph.D.
7

Characterisation of unresolved complex mixtures of hydrocarbons by degradative methods

Revill, Andrew Thomas January 1992 (has links)
Unresolved Complex Mixtures (UCMs) of hydrocarbons are found in crude and refined oils and in water, sediments and biota polluted with oils. The concentrations of UCMs in oils are significant (e.g. >65% of the aliphatic hydrocarbons in fresh Kuwait crude) and it is perhaps surprising that virtually nothing is known about UCM composition. The present study sought to redress this paucity of information in three main ways: First, following two recent studies of aliphatic UCMs, an investigation of the composition of the "aromatic" UCM of Venezuelan Tia Juana Pesado crude oil was made by spectroscopic (IR, NMR, MS) and oxidative (CrO3, Ru04) methods. These showed that the UCM was, in fact, highly aliphatic. The major compounds identified were alkyl substituted naphthenoaromatics with one and two aromatic rings. Chemical oxidation indicated that the alkyl branched side chains extended to at least twenty three carbon atoms. Second, an investigation into the origins of UCMs was made. The products of hydrous pyrolysis of man-made (polythene) and biogenic (cutan) polymers under conditions proposed previously to simulate catagenesis, included, in the hydrocarbons, high proportions of UCMs (50% - >70%). Hydrous pyrolysis of polythene produced a mixture of saturated (56%) and olefinic (44%) hydrocarbons, whilst pyrolysis of cutan produced hydrocarbon (aliphatic and aromatic; 30-75%) and nonhydrocarbon (70-25%) fractions, both with >60% unresolved components. Oxidative characterisation of these UCMs produced mainly n-acids with somewhat similar results to those found when oil UCMs were oxidised. However, the laboratory generated UCMs are not perfect oil UCM models since some oil UCM oxidation products were not observed in the laboratory models. Finally, an attempt was made to release the geochemical information contained within UCMs. Replicate oxidations of milligram quantities of oil UCMs followed by quantitative GCMS characterisation and multivariate statistical analysis of the resolved oxidation products gave reproducible distributions with >80% similarity. Application of this method to two oil spill incidents where the source oil was known (Milford Haven and the Humber Estuary) gave good correlations between sediment and source. In contrast analysis of Mersey Estuary sediments contaminated with heavy asphaltic oil and of Sullom Voe sediments contaminated with UCMs failed to show any correlation between the sediments and the source oils. However, subsequent re-analysis of the data excluding the major UCM oxidation products (n-carboxylic acids) produced better correlations which indicated that the greatest correlation potential for these UCMs was contained within the minor oxidation products. A similar study of UCMs from two oil seeps from the Siljan Ring region of Sweden failed to show any correlation with potential source rocks, in agreement with biomarker data. This study has extended present knowledge of UCM composition and suggested a mechanism for UCM formation. Furthermore, quantitative and statistical analysis of UCM oxidation products has been shown to be useful for oil identification. There is still much to be learned about UCMs and the subject should provide a fruitful area for further research. Some possible approaches are suggested. Parts of this work have been published (Revill et al. 1991), Organic Geochemistry: Advances and Applications in Energy and the Natural Environment, Manchester University Press
8

Factors affecting the yields and properties of the products of the low-temperature carbonization of Penn-Lee coal fromm southwestern Virginia

Disney, John Lillis January 1957 (has links)
The purpose of this investigation was to study the factors affecting the low-temperature carbonization of seam number one, Penn-Lee coal from southwestern Virginia, by determining the effect of pretreatment of the charge, temperature of the retorting gas, and time of retorting on the yields and properties of the products of carbonization. After an examination of the literature pertinent to the investigation, a pilot-scale carbonization unit was constructed. The construction of the unit consisted partly of the modification of an existing fluidization unit. Various auxiliary apparatus were also added to the modified unit for more satisfactory operation. A series of bench-scale tests were performed to study the effect of pretreatment conditions on the free-swelling index, the weight loss, and the volatile matter in Penn-Lee coal. Time and temperature had a significant effect upon the free-swelling index. Temperature of pretreatment had a significant effect on the weight loss during pretreatment. Time and the time by temperature effect were found to be significant with regard to the volatile matter remaining in the coal after pretreatment. Also, the decomposition point of Penn-Lee coal was found to lie between 427 and 454 °C (800 and 850 °F). Twelve pilot-scale tests were performed to study the effect of carbonizing conditions on the products of carbonization. The pretreatment time had a significant effect upon the dry tar yield, the tar viscosity, the tar specific gravity, and the twenty per cent tar distillation temperature. The time of carbonization had a significant effect upon the gas yield. None of the variables studied showed a significant effect within the range studied, upon the volatile matter in the char product, the bulk density of the char, or the calorific value of the char. / Ph. D.
9

A calorimetric study of the immersion of bituminous coal in liquids

Hollenhead, James B. 13 October 2010 (has links)
The surface properties of coal greatly affect its use in industrial processes such as gasification, liquefaction and the use of coal slurries. In addition, such processes also involve reagent penetration into coal pores and the oxidative state of the coal surface. Reagent penetration into coal was examined by determining the heat and kinetics of immersion of Pocahontas No. 3 coal in water, methanol, a series of n-alkanes, and several cyclic and heterocyclic hydrocarbons. Results indicate that the heat of immersion is sensitive to the carbon chain length of the wetting liquid and its ability to hydrogen bond to coal. The time of immersion is insensitive to carbon chain length but is increased by the presence of nitrogen in a cyclic hydrocarbon. The oxidation of both unextracted and extracted coal at 3200C was followed by immersional measurements in water. The heat of immersion increased rapidly with oxidation time, leveling off after 3 hours of oxidation. Extraction with methanol or pyridine prior to oxidation and immersion lowered the time of immersion in water compared to the unextracted case. The oxidation of coal was also followed by x-ray photoelectron spectroscopy (XPS). The XPS oxygen/carbon ratios correlated linearly with the heats of immersion for the extracted, oxidized coals. Thus, XPS was shown to be a useful ancillary technique to heat of immersion for the study of coal surfaces. / Master of Science
10

Influência do método de lavagem nas características de carvões antracitoso e betuminoso utilizados em meio filtrante / Washing method influence on anthracite coal and betuminous coal properties used in filter media

Wiecheteck, Giovana Kátie 27 September 1996 (has links)
Teve como objetivo verificar e comparar a alteração das características do carvão antracitoso e do carvão betuminoso utilizados em meio filtrante, devido ao efeito abrasivo causado entre os grãos decorrentes de lavagens exclusivamente com água e lavagens independentes com ar e água. Foram estudados dois tipos de carvão antracitoso e um tipo de carvão betuminoso, para os quais foram determinadas suas características químicas e físicas. Os ensaios foram realizados em uma instalação ao piloto montada na escola de engenharia de São Carlos-EESC, USP, na qual foram feitas simulações de lavagens admitindo-se uma lavagem diária durante um ano para cada método, de modo intermitente, em que o meio granular era compactado ao final de cada lavagem, e continuo, sem compactação do meio granular. A velocidade ascensional utilizada para cada simulação de lavagem foi de 0,9 m/min, promovendo expansão no meio granular de 35 a 40%. A taxa de ar utilizada para as simulações de lavagens com aplicação de ar foi de 15 l/sm2. Após o término das 365 lavagens, foram determinados os valores médios do coeficiente de esfericidade e da porosidade do meio granular estratificado e construída a curva de distribuição granulométrica das amostras utilizadas nos ensaios. Conclui-se que o carvão betuminoso apresentou comportamento semelhante ao dos carvões antracitosos e que a metodologia de lavagem continua produz praticamente o mesmo efeito abrasivo comparada a de lavagem intermitente. / This work had the objetive to verify and to compare the alterations on the properties of Anthracite coal and Betuminous coal, due to the abrasive effect caused between the grains resulted from washing exclusively with water and independent washing with air and water. There were studied two types of Anthracite coal and one type of Betuminous coal, their chemical and physical properties were determined. The tests were performed at a pilot instalation setted at the School of Engineering of São Carlos - EESC,USP; where, were done simulations of washing, it was admitted one washing a day during one year (365 washing) for each method, in an intermitent way, in which the granular medium was compacted at the end of each washing, and continous without compactation of the granular medium. The ascending speed used for each simulation of washing was 0,9 m/min, promoting an expansion in the granular medium of 35 to 40%. The rate of air used for the simulations of washing with the aplication of air was 15 I/sm2. After the last of the 365 washing, were determined the average values of the coefficient of sphericity and porosity of the granular estratified medium and was constructed a curve of the granulometric distribution of the samples used during the tests. It was conclued that Betuminous coal shows similar behaviour as Anthracite coaI and the continous method produce the same effect abrasive compared intermitent method.

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