Sludge discharge device of sedimentation tank and sewage sedimentation system

The utility model relates to the technical field of sewage treatment of thermal power plants, in particular to a sedimentation tank sludge discharge device and a sewage sedimentation system, and the sedimentation tank sludge discharge device comprises a power component, a lead screw and a push plate which are connected in sequence; the inner bottom wall of the sedimentation tank is obliquely arranged; the lead screw is parallel to the inner bottom wall of the sedimentation tank; the push plate is in threaded connection with the lead screw; the side end of the push plate is slidably connected with the side wall of the sedimentation tank; the bottom of the push plate is slidably connected with the inner bottom wall of the sedimentation tank; the power assembly drives the lead screw to rotate, and the push plate moves to scrape and push sludge to the sludge discharge port; the sewage sedimentation system comprises a sedimentation tank sludge discharge device and a sedimentation tank, and the discharge mechanism