Effect of geological processes on coal quality and utilization potential: review with examples from western Canada

This review article compares the elemental and radionuclide concentrations in coals from western Canada, the vast majority of which are used for power generation in Alberta. The coals range in age from lower Cretaceous to mid dle Eocene, and in rank from subbituminous to high volatile bituminous. Som e of the coals were deposited in deltaic lagoonal to marine settings while others formed under lacustrine conditions in intermontane graben settings o r in alluvial plains. The role of source rock (provenance), depositional en vironment, tectonic regime and hydrologic conditions on elemental concentra tion and distribution will be discussed, with specific examples from wester n Canada. In addition, the effect of natural weathering, igneous intrusion and self-burning (spontaneous combustion) on the enrichment and/or depletio n of elements will be presented. The emphasis throughout this review articl e will be on the fate of elements of environmental concern and interest (e. g. As, Ba, B, Cl, Co, Cr, Cu, Mn, Mo, Se, Th, U, V and Zn) and of radionucl ides of the U and Th series upon coal utilization. This article is also int ended for those not familiar with the geological or environmental sciences, particularly as related to fossil fuel utilization. (C) 2000 Elsevier Scie nce B.V. All rights reserved.