Abstract: A filter press plate shifter assembly (21) provided with a shifter housing (22) having a tunnel-like center part which passes over the filter plates and housing parts positioned adjacent opposite side rails (14). Each side housing part mounts a pneumatic plate shifter (41) for permitting the endmost plate in the closed stack to be individually and sequentially shifted away from the stack into an open position when discharge of filtrate is desired. The shifter housing mounts a bumping device (61) which cooperates with the endmost plate in the stack to effect vertical bumping thereof relative to the support rails to assist in loosening sticky cake which adheres to the plate. The shifter housing also mounts an air-assist discharge mechanism (62) which includes a nozzle-bearing head assembly (80, 80') which moves vertically downwardly between the opposed faces of an open pair of adjacent plates for discharging airstreams downwardly against the plates to assist in removing the sticky cake from the plates.

Abstract: A drier having a boxlike housing (12) for receiving a hopper (13) therein which contains a batch of wet sludge. The hopper (13) cooperates with the housing, when closed therein, to define a closed air recirculation system which supplies dry pressurized warm air into an air-receiving chamber (79) located at the bottom of the hopper. The air passes upwardly through a perforated bottom wall (78) into and through the sludge to remove moisture therefrom. The moist air passes upwardly through the open top of the hopper, through a filter and is supplied to a drying unit (34) located in the housing for removing moisture therefrom, which moisture is externally discharged. The drying unit resupplies the dry air back to the drying chamber formed in the hopper.

Abstract: A method for controlling the filling of a filter press with slurry according to a preferred embodiment of the present invention includes the sequentially executed steps of: gradually increasing the pressure of the slurry supplied to thee press until the slurry pressure reaches an upper pressure limit; recording a trigger point in time at which the slurry pressure reaches the upper pressure limit; and determining whether the slurry pressure subsequently falls below a lower pressure limit within a predetermined period of time commencing at the trigger point. If the slurry pressure does fall below the lower pressure limit within the predetermined period of time, then the above-listed sequence of steps is repeated until the slurry pressure fails to fall below the lower pressure limit within the predetermined period of time, thereby indicating that the press is full and terminating the process.