Based on KZG550-type quick-open diaphragm filter press in the structure, working principle, technical parameters, performance analysis, combined with inclined ditch coal mine coal preparation plant of the production practice, introduces its for fine coal slime recovery.Nearly six years of production practice showed that KZG550-type quick- open diaphragm filter press equipment performance is good, effectively improve the efficiency of the recycling of slime water system, reduces the concentration of washing water, meet the requirements of the customers on the coal slime water, filter the coal moisture content is 24% ~ 26%, the dewatering efficiency of over 80%, annual concentration of washing water stability under 10 mg/L, it is an ideal equipment of slime water solid-liquid separation.