Stabilization of coal cleaning wastes. Fossil Energy Program. Technical progress report, 1 January 1986-31 March 1986

This report describes current research on the stabilization of waste from the mining and cleaning of coal by sintering. The refuse used is from subbituminous coal processed in the River King Coal Preparation Plant, Freeburg, IL. For the work described in this report, the refuse was ground in a single pass through a Holmes hammer mill having a screen with 3/16 inch round openings. The characterization of this material, including size distribution, elemental analysis, carbon and sulfur content, loss of ignition, bulk density, and higher calorific value, was completed during this quarter. Using a disc agglomerator operated in a continuous manner, green pellets were produced from a 75:25 refuse:fly ash mixture with water as the only binder and fly ash used as a diluent. The pellets formed were examined and subjected to standard durability tests - the ASTM drop shatter, the rotap, and the drops-to-failure. When sintered in a laboratory combustor at various temperatures, the pellets were found to be unagglomerated and quite strong, but varying somewhat in color. X-ray diffraction was used to explain a relationship thought to exist between this color variation, composition, and the durability of the sintered pellets. Green pellets were also prepared from a mixturemore » of refuse and FGD sludge with water as the only binder. An investigation on how the durability and composition of these pellets varied with changes in water addition was also completed. 1 ref., 7 figs., 5 tabs.« less