A typical coal resource characterization study calls for estimating thickness, density, and quality parameters over a block or node simultaneously. Traditionally, estimation has been done for each variable independent of the other variables. The methods range from the well known polygonal and distance weighting methods to the geostatistical method of kriging. None of these methods takes the correlations between the variables into account explicitly. A comprehensive study has been undertaken to determine whether the joint estimation technique of cokriging may be used to utilize intervariable correlations in increasing the accuracy of estimation. Seam thickness, density, ash, calorific value, and sulphur have been studied to determine whether they are cross-correlated. Significant cross-correlations have been found to exist between ash content, density, and calorific value, where the rank of the coal is stable. A survey and a case study indicated that seam thickness may also be cross-correlated with ash content and density. Subsequently, separate kriging and cokriging results have been subjected to comparison via a cross-validation procedure. After normalization, cokriging has provided substantial improvements over kriging in estimating thickness, density, and ash content. Moreover, cokriging performed well in replicating the correlation schemes where kriging occasionally failed. In this study, geostatistical methods have been found to produce results in compliance with their probabilistic premises. A general purpose geostatistics software package has been written to carry out modeling and part of the research on a personal computer. This package has been designed to provide many advantages over the existing costly and black-box type software. / Ph. D.

Due to many unexpected difficulties which developed as the method was being worked out, all of the desired information on these coals was not obtained. Therefore, most of the allotted time has to be devoted to the standardizing of the apparatus. Many of the small but important points of technique, which gave trouble, have been overcome. / M.S.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Call number: LD2668 .T4 1978 W43 / Master of Science

Call number: LD2668 .T4 1979 H69 / Master of Science

No description available.

This research investigates financial, technical and attitudinal factors affectine the selection of coai as a space heating fuel in Local Authorities' non-domestic premises. Financial factors are explored by incorporating statistics of a sample of The City of Bradford Metropolitan Council's sites into a computer model that takes into account: the spread of capital costs of installing coal or other fuels. delivered fuel costs. maintenance and operating costs. and seasonal boiler efficiencies. The sensitivity of the mooei to changes in costs. boiler efficiencies. and financial selection criteria are investigated. Assuming a five year payback criterion and prices as found at the end of 1966, three percent of the space-heating ruel use or the Local Authority's premises is found to be viable for coal. The model is sensitive principally to changes in capital costs. and the availability of gas if a high cost for oit is assumed. Technical tactors are investigated by describing the properties or coal ana available comoustion equipment. Attitudes to the use of coal are researched by interviewing a sample of otticers and members in six Local Authorities in Yorksnire ana Humberside. Interviewees were particularly encouraged to describe their impressions and beliels. The scope of the study is expanded by the use of a postal survey of all United Kingdom Local Authorities. A variety or different topics are considered in the survey. These include the presence and content of fuel selection policies. the use and cost of fuels. financial criteria adopted in assessing projects, availability fr as supplies, and attitudes to the use of coal. The response rate to the questionnaire was over 40%. The study concludes with recommendations to The City or Braotora Metropolitan Council and British Coal.

No description available.

A mechanism for the oxidation and fragmentation of a char particle was developed. Qualitative agreement between the model simulations and experimental data observed in the literature, is found for the higher gas temperatures (1700K). However fundamental differences are found in the particle temperature histories and burnout times at low temperature (1250K). The role that fragmentation plays on the char particle history is incorporated into the model and the possible production of fine particulate through fragmentation is examined. A relatively large fraction of the mass of char available for fragmentation is produced early in the combustion history of the particle. Therefore, if this mechanism is important in the generation of fine particulate matter during char combustion, the simulations indicate that it would occur early in the combustion process. Due to the limited experimental data in the literature on the time resolved particle size distribution in the early stages of combustion, corroboration between model and experiment was not possible.

No description available.