Sludge dehydrator

The utility model discloses a sludge dewaterer which comprises an outer cylinder, an inner cylinder is mounted in the outer cylinder, the top of the inner cylinder is rotatably connected with a dewatering cylinder, at least two bottom plates are hinged to the inner bottom wall of the dewatering cylinder, a guide cylinder is arranged at the bottom of the dewatering cylinder, and limiting mechanisms matched with the bottom plates are mounted on the guide cylinder. According to the sludge dewaterer, through cooperative arrangement of the dewatering cylinder, the limiting mechanism and the driving mechanism, when the telescopic end of the cylinder body stretches out, the dewatering cylinder rotates forwards to dewater sludge, and when a pressing disc moves downwards to a certain position, the sludge can be extruded, and then secondary dewatering is conducted on the sludge, so that the dewatering effect of the device is further improved; the bottom plate is automatically opened, and when the telescopic end of the