Municipal building drainage energy-saving device

The utility model belongs to the technical field of drainage devices, and relates to a municipal building drainage energy-saving device which comprises a main water pipe, the tail end, in the water flow direction, of the main water pipe is communicated with a water storage pool, the pool wall of the water storage pool is communicated with a feeding pipe, the bottom of the water storage pool is communicated with a drainage assembly, and the bottom of the water storage pool is communicated with a dirt collecting hopper. A cleaning mechanism used for cleaning the inner wall of the dirt collecting hopper is arranged in the dirt collecting hopper, the bottom of the dirt collecting hopper is communicated with a blow-off pipe, and a valve is installed at the end, away from the dirt collecting hopper, of the blow-off pipe. The sewage purifying agent has the effect of solving the problem that impurities in sewage are precipitated at the bottom of a reservoir after being flocculated and precipitated by the sewage purif