Evaluation of a Novel Fine Coal Dry Cleaning Process at Greenfields Coal Company

Abstract

Coal mining and processing operations have in the past and continue to create large tonnages of fine coal and waste particles. While technological advances in wet processing has made it possible to efficiently recover coal fines, difficulties associated with dewatering make these fine particles unattractive economically for most coal markets. A novel system has been developed for cleaning fine raw coal utilizing a multistage dry classification process that removes the clay particles that are typically much smaller than the majority of the clean coal particles and that reduces the product surface moisture to as low as 1%. In this article, the novel dry coal-cleaning process under license to Greenfields Coal Company was evaluated. The classification process offers a viable alternative to traditional wet processing and dewatering of the fine particles, especially for operations recovering abandoned impoundments where a sufficient water source and/or a waste slurry disposal site are unavailable. This article presents the separation performance and operating results obtained from field testing with a 2 t/hr pilot-scale unit located at an abandoned impoundment in southern West Virginia.