Abstract: In order to solve the problems of poor dewatering effect,long cycle of material discharge and high consumption of power of GPJ-120 pressure filter in Tunlan coal preparation plant,using KZG450 /2000-U quick open diaphragm filter press to replace the original pressure filter for the flotation concentrate dewatering.The paper introduces the structure,working principle,technical characteristics and technical parameters of filter press,also discribed its application effect.The practice shows that the KZG450 /2000-U quick open diaphragm filter press has better dewatering result,greater processing capacity,lower power consumption,can effectively improve the processing capacity of flotation concentrate,substantially reduce the cost of equipment maintenance.