Creating additional revenue streams prior to the disposal of tailings

Coal production at mine sites and consumption by end users generate a considerable amount of waste. Over the past 100 years, coal production processes combined with ongoing increases in energy demands have resulted in 100's of millions of tons of waste across the world. The management of coal waste containing numerous harmful properties with potential environmental and human safety risks is often compromised by financial constraints of the businesses generating the waste. During the past decade, efforts have been made to find more responsible ways of disposing of mine waste and tailings. This has followed a series of serious global environmental impacts including waste dumps and tailings storage facility failures, run-off water pollution, and spontaneous combustion incidents. For coal mines, this has created many opportunities for more effectively dealing with all of these unwanted outcomes. One collective solution that has emerged has been to seek opportunities for revenue generation by creating secondary products from within the waste streams. This can occur by recovering fine coal from a tailings stream and using the extra revenue toward the cost of a dry disposal solution, employing some form of reconcentration of run-of-mine coal to remove useful material, or separating this valued material from rejected material emanating from washing plants. In the post utilization stages, this can involve utilization of ash and slag materials or recovery of useful metals. This article discusses some of the more commonly encountered opportunities for coal waste disposal and their potential application in terms of revenue generation.