Abstract: The Huai dong coal of Xinjiang have abundant resources and thick coal seam, but in the mining process, the coal is instability, because of mixing with the top, the bottom and the entrained gangue ,and must been sorted. Such as the design of coal preparation plant matched with Da jing nan mine, the process including the coal ash forecasting, data adjustment and process determination are described .The principles and elements to pay attention are proposed. It has a good guidance to design large coal preparation plant of power coal in the area.

Key words: Coal forecasts, adjustable gangue, shallow groove heavy medium for lump, relaxation sieve