Abstract:
Based on the analysis of 8 samples of raw and cleaned coal collected from 4 coal-washing plants and the results of simulated coal cleaning experiments for 2 raw coals, removability of ash, sulfur and 20 hazardous trace elements in these samples during coal cleaning were studied. Combined with the previous works, cleaning potential of the hazardous elements were systematically discussed. The results suggested that physical coal cleaning was not only a mature technology as applied to the removal of ash and sulfur, but also effective in reducing the concentration of hazardous trace elements in varying degrees. It was anticipated that more than 50% of ash and the hazardous elements As, Co, Cr, Cu, Hg, Mn and more than 30% of sulfur in most coal would be routinely removed by physical coal cleaning procedures, however, the removability of other hazardous elements Ba, Be, Cd, Cl, Mo, Ni, P, Pb, Sb, Se, Th, U, V and Zn displayed relatively lower or a wide range of variation.