In view of the serious slime of raw coal in Xingtai Coal Preparation Plant, the high-ash fine slime is entrained in the feed of coarse slime, and the separation efficiency of grading equipment is low, which leads to the prominent problem of tailings ' running coal '.In this paper, a number of measures are taken to optimize the system process and equipment. In order to improve the recovery rate of clean coal, combined with its own coal quality characteristics, from the perspective of the whole system, under the premise of not affecting the separation of other links, the particle size composition of the feed is controlled as much as possible, and the high-efficiency grading and desliming equipment is selected. At the same time, the closed circuit of the system is unblocked to prevent the agglomeration of fine slime and improve the recovery rate of coarse slime.