Characterization and Evaluation of Washability of Alaskan Coals: Selected Seams from Nenana, Jarvis Creek and Matanuska Coal Fields. Final Technical Report for Phase I, September 30, 1976-June 30, 1977

摘要

This report covers the results of a study conducted to obtain washability data for Alaskan coals to supplement the efforts of the US Department of Energy (formerly US Bureau of Mines) in its ongoing studies on washability of US coals. Alaska has 130 billion tons of identified coal resources and could be in a position to supply environmentally acceptable low-ash and low-sulfur coals to other states. Preparation characteristics were obtained for nine coal samples collected from the Nenana, Jarvis Creek, and Matanuska coal fields. The raw coals were crushed to 1 1/2 inches, 3/8 inch, and 14 mesh (Tyler) sizes and float-sink separations were made at 1.30, 1.40, and 1.60 specific gravities. The results showed that six subbituminous C coals from the Nenana coal field, when crushed to minus 14 mesh and floated at specific gravity 1.40, yielded products ranging in heating values from 10,098 to 11,664 Btu/lb with 0.15 percent to 0.23 percent sulfur on a moisture free basis, making them among the most environmentally acceptable coals in the United States. A subbituminous C coal from the Jarvis Creek coal field yielded 84.9 weight-percent of float 1.40 specific gravity product with 11,272 Btu/lb on a moisture free basis and 0.98 percent sulfur after crushing to 14 mesh top size. A high volatile A and a high volatile B bituminous coal from the Matanuska coal field yielded 65.7 and 75.3 weight-percent of float 1.40 specific gravity product with heating values of 14,383 and 13,371 Btu/lb when crushed to 14 mesh top size. The sulfur in these two coals was very low (less than 0.50 percent) and was virtually all organic sulfur; therefore, no sulfur reduction occurred during washing. (ERA citation 05:021715)