六十年代初期以前,不少单位采用BL-240过滤泵即所谓水环式离心过滤机。但它噪音大、易锈蚀,逐渐被真空过滤机所取代。即沿用以前的过滤盘,接以贮液瓶,再连接真空泵进行抽滤。采用上述过滤设备时,由于盘面直径大(240—250毫米),当对少量试验产品(如精矿、中矿或经湿式缩分后的少量尾矿)过滤时,往往出现 Before the early 1960s, many units used the so-called water ring centrifugal filter BL-240 filter. But it is noisy, easy to rust, gradually replaced by a vacuum filter. That is, use the previous filter plate, connected to the storage bottle, then connect the vacuum pump for suction filtration. With the above filtration equipment, there is often a small amount of test product (such as concentrate, middlings or wet tailings tailings) due to large disk diameters (240-250 mm)