Clean Coal: Demonstration of a Novel Dry Course Coal Process for Improved Mining Economics

PUBLIC ABSTRACT The extraction of coal typically results in the recovery of pure rock that ranges from small to very large quantities depending on seam thickness and other characteristics. The eastern Kentucky coal fields, which contain the highest quality coal in the U.S., retain nearly 85% of the original coal reserves or 64 billion ton after two centuries of escalating production.. However, approximately 80% of the remaining coal exists in seams with a thickness less than 42 inches. To extract these coals economically, a large amount of rock from the roof and floor is recovered with the coal. The average amount of rock in run-ofmine eastern Kentucky coal ranges from 60% - 70%. The haulage, processing and storage of the rock equate to elevated mining costs, poor energy inefficiency and a significant impact on the environment due to the need for large off-site storage areas. Ideally, the majority of the pure rock should be removed near the extraction point and placed back into the mined out areas, thereby, minimizing the negative impacts. The removal of the pure rock, generally referred to as 'deshaling', needs be achieved using a dry separation process to avoid the need for water treatment facilities at the mine site. A novel dry coal processing technology that has the potential to efficiently remove pure rock from coal has been developed to commercial-scale and is known as the Accelerator. The Accelerator technology selectively breaks the coal away from the rock by slinging the coal using rotors into a plate that has perforated holes of a predetennined size. The shock created by the impact of the coal against the plate causes selective breakage between the granular boundaries between the coal and rock. As such, purer particles of coal and rock are produced. As the material continues through multiple stages of breakage, the coal particles size reduces at a rate greater than that of rock due to the differential hardness between rock and coal. As such, the Accelerator product can be screened at a given size (e.g., 2 inches) to remove the coarser rock material. Also, due to the impact breakage, the cleaning characteristics of the material that reports to the preparation plant are improved which should produce an increase in coal recovery and thus reduce the loss of coal to the reject storage areas. The Accelerator technology is represented by Imperial Technologies Incorporated. There are no units operating in Kentucky, the Central Appalachia coal fields and the Illinois coal basin. A diverse team comprised of a research university (University of Kentucky), a leading coal producer in Kentucky (James River Coal Company) and a process equipment manufacturer (Imperial Technologies Inc) has been assembled to undertake the demonstration ofthe Accelerator technology. The goal of the project is to demonstrate the potential of the Accelerator technology to improve coal mining economics in Kentucky and to reduce the environmental impacts of extracting coal. To achieve this goal, James River Coal Company will provide five sites in Kentucky to test the Accelerator. These sites will include mining operations in the Kentucky coal producing counties of Pike, Perry and Leslie. Imperial Technologies will supply a mobile 250 ton/hr Accelerator unit and technical assistance for the test program. A test program developed and administered by University of Kentucky researchers will ensure optimum conditions are realized for the coals tested at each site. Based on a preliminary assessment, deshaling at a typical 1,000 tonlhr operation could provide an annual revenue increase of around $10 million with the overall value of removing a ton of rock being $50. If successful, increased profits would be realized trom an increase in clean coal production per ton of runof- mine coal and a decrease in operating costs associated with transportation fuel and labor costs as well as a reduction in disposal expenses. 11