Abstract: To solve the problem of poor quality of raw coal encountered in Renjiazhuang coal preparation plant,proposed that adding desliming screen at the position before the dense medium process for pre-desliming,and the coarse slime in underflow of the desliming screen was recovered by combined process of cyclone classifier + TBS teetered bed separator,The results of production indicated that this process proved have significant recovery effects to the coarse slime.