Abstract: Following an introduction to the flotation system in current use at Zhaolou Coal Washery,the paper makes an analysis of the property of the feed coal and a comparison of the performance of the KHD pneumatic flotation machine and the XJM-S subaeration version. Then,the paper goes to elaborate on the flotation process with the abovementioned 2 types of machines working in series. As indicated by actual operating performance,the flotation process works remarkably well,making it possible for the washery to effectively increase the recovery of combustible matters and yield of concentrate.