Abstract: In order to achieve the two-fold objective of reducing the moisture of flotation concentrate while increasing the efficiency of filter press,the method of mixing the flotation concentrate with the coarse particles obtained from the overflow of the coarse slime separator（ CSS） is adopted. Through an analysis of the effect on cake moisture and efficiency of the filter press produced by variation of size composition of the feed of filter press,the most appropriate blending scheme is defined. Practice shows that when the ＜ 0. 045 mm size coarse slime is added into flotation concentrate in a proportion of around 40%,the filter press can work with the optimal performance in terms of working efficiency and the extent to which the cake moisture is reduced.