ABSTRACT

In the past, qualitative measurements of various properties such as heat value, fixed carbon, moisture, ash, sulfur, phosphorus, and coking and grindability characteristics have been the parameters used for coal utilization assessments. Now, however, more quantitative geologic and geochemical data are necessary for a comprehensive coal-resource assessment because of 1) the development of sophisticated conversion processes, 2) environmental constraints related to coal usage, and 3) the probability that coal contains recoverable mineral by-products. Gathering such data involves sampling, analysis, and subsequent studies on the modes of occurrence, concentration, and distribution of elements both stratigraphically and geographically within a coal bed and a coal basin. In the technological and environmental realms, many of these elements can affect coal reactivity, gaseous and liquid yields, and planned waste disposal, reclamation, and revegetation. Knowledge of various elements in coal will aid in developing the ability to: 1) predict elemental distribution, concentrations, and coal properties in localities where data are sparce; 2) incorporate these data into different classes of coal resources; and 3) categorize coal resources for metallurgical, gasification, liquefication, petrochemical, and blending usages. Necessary determinations include ash-fusibility temperatures, mineral-matter mineralogy, petrologic charactistics, sulfur forms, pertinent washability data, and the major-, minor-, and trace-element chemistry of coal.

Measurements necessary for resource quantity and quality calculations include: 1) thickness, rank, and quality of coal, 2) depth of the coal bed, and 3) the proximity and density of the coal resource data points upon which the estimate will be based. Various combinations of these measurements allow the establishment of different resource classes and the estimation of tonnages within each class. The integration and aggregation of quantitative and qualitative coal data with sedimentologic, stratigraphic, and structural data will provide a framework for determining the most efficient use of coal resources by ensuring maximum energy efficiency and conservation while maintaining environmental integrity.