Abstract: For avoiding the loss of coarse slime during coal cleaning process, work is made on the technical transformation of the existing coarse slime separation system. Following an introduction to the structure, working principle, technical features and parameters of the TCS separator, comparative analysis is made of the performance of the separator in operation at Guandi plant. Practice shows that the separator is high in sharpness of separation, and its use makes it possible to effectively treat the 0.5-0.125 mm fine coal, improve the overall operating efficiency of the plant, maintain a stable separating density, increase yield of clean coal product, and reduce medium consumption and , hence, operating costs.