Valorization of South African Coal Wastes through Dense Medium Separation

Sustainable management of coal waste is one the major environmental concerns for mining, whether active or legacy, worldwide. Coal dump deposits demand a large physical area footprint disposal solid waste, change topography, and generate both pyritic dust acid rock drainage (ARD) where deposited. The beneficiation or, preferably, prior to its dumping can reduce even eliminate liabilities related management. In this work, dense medium separation studies discards, using heavy liquids, resulted in three pooled fractions from typical South African discards Mpumalanga region future use: (a) fraction low density with increased calorific value; (b) intermediate density, rich ash neutralizing minerals lower sulfur; (c) high sulfidic including pyrite. were characterized particle size analysis, sink-float studies, static tests predict ARD potential, proximateand ultimate gross value. results showed that approximately 70% discard composed material sufficient quality energy generation conventional power stations. A pyrite-rich concentrate made up 2% total mass; comprising more than 45% mineral present feed displaying no capacity (ANC). remaining fraction, presented potential be used several ends soil fabrication, co-disposal as aggregate civil engineering; additional testing ensure applicability selected re-purposing option should chosen based on proposed use.