Abstract: With the continuous advance of the mining face of Jinjie Coal Mine, the phenomena of degradation in water of rock waste in raw coal is becoming increasingly serious, causing as a result continuous rise of proportion of high-ash fine coal in the plant′s raw coal feed, imposing a big load on slurry water thickening, settling, dewatering systems and exerting harmful influences on quality of fine coal product, control of operating cost, boosting of percentage of raw coal treated, and circulating water purification to varying extent.Considering the property of raw coal and degree of degradation of waste in raw coal, two plate-and-frame filter presses are added in the coarse coal cleaning system for dewatering of fine slime in combination with the pressure filters currently used.The other reform is the switching of the thickening process from a parallel circuit to a tandem one.Practice shows that the renovation and optimization work has led to a rise of proportion of coarse coal treated by 4 percentage points and a decrease of moisture of slime product by 1.34 percentage points, greatly upgrading the plant′s coarse coal and blended coal products.