Abstract: Analyzed the problem in flotation clean coal dewatering system in Luling coal preparation plant,introduced the two stage dewatering process that is the flotation directed dewatering with horizontal solid bowl centrifuge,the overflow and filtrate desliming and then go to secondary flotation or direct flotation,the clean coal produced dewatered by secondary dewatering process using quick open filter press,which eliminated the effect of concentrate froth on production,solved the problem of difficult to dewatering of flotation clean coal in Luling coal preparation plant.