Abstract: A mobile transfer device is provided with a high-pressure piston pump connected to a conveyor pipeline having a portion upstream of the pump forming a suction pipe, an elongated loading shovel being provided at a forward end of the transfer device disposed transverse thereto, with means connected between the transfer device and the shovel for raising and lowering the shovel, an elongated screw conveyor being disposed in the shovel longitudinally thereof at a rear wall of the shovel, the screw conveyor having a conveying end point at an inlet of the suction pipe which opens into the shovel, and an elongated stamping mill provided in the shovel above the screw conveyor and parallel thereto and being provided with a plurality of swingable stampers distributed therealong and adapted to engage sludge in said screw conveyor for treatment thereof.