Abstract: In order that higher demands on the purity of the separated liquid can be satisfied, a cleaning plant (12) having wash chambers (13a,b) for the cleaning of the filter plates (8) is arranged in longitudinal direction alongside of a filter press (1). By means of a transport device (30) having a displacement device (32) which is moveable along rails (31a) and is equipped with a raisable and lowerable gripper (37) which can be engaged via pawls with filter plates (8), the filter plates, after the opening of the filter press (1), are transported one after the other into the cleaning plant (12), sprayed in one of the wash chambers (13a, b) with simultaneous drawing off of the air or subjected to an immersion bath, possibly disinfected or impregnated, dried and transported back. By the development of the cleaning plant (12) with two wash chambers (13a, b), idle paths of the displacement device (32) are substantially avoided.