Abstract: Because of the high proportion of fine sizes in raw coal treated by Liujiakou Coal Preparation Plant, a series of problems arises, such as high load on slime treatment system, medium consumption maintaining at a high level, and freezing up of rail car-loaded coal in winter, etc. To cope with this situation, work is made on the fines removal system of Liujiakou Coal Preparation Plant through introduction of the double-layer flip-flop screen. Application of the screen has led to easing of the load imposed on coal slime treatment system, elimination of blockage of rail cars due to freezing of coal, reduced consumption of both medium and reagents, increased yield of clean coal, and improved economic benefit.