Cleaning of South African coal using a compound dry cleaning apparatus

The compound dry cleaning principle is briefly described. A beneficiation test on South African coal was conducted using a model compound dry cleaning apparatus. Excellent results were obtained and the optimum operating parameters were determined. They are: an amplitude of 3.0 mm, a motor frequency of 47.5 Hz, an air volume of 50%, a transverse angle of 7°, and a longitudinal angle of −2°. These conditions yield a clean coal containing 11% ash and a coal production of 75%. The organic efficiency, η, is 95.86%. These results show that the South African coal can be separated effectively by compound dry cleaning, which will popularize the compound dry cleaning method.