The efficacy of dry coal cleaning for high-density separations

Maximizing the recovery of coal reserves and optimizing coal operations have been a focus of recent attention. Past practices in the western U.S. discarded the coal near the top and floor of large surface mining operations rather than cleaning the material through a preparation plant. In many situations in the eastern U.S., coal and associated rock are hauled over long distances to the preparation plant where the rock is separated from the coal, hauled and disposed into a refuse area. In an effort to improve coal mining economics, an evaluation has been performed to determine the feasibility of removing high-density rock from the coal using a dry, density-based technology at the mine site. Using a 5 tph mobile unit, approximately 70% of the rock comprised in a run-of-mine coal was removed while recovering nearly 100% of the coal. The ash content of the tailings stream was greater than 80% in many tests. The results obtained from on-site tests at western and eastern U.S. coal operations will be presented and discussed in the publication.