Flocculation mixing tank with pre-concentration function

The flocculation mixing tank with the pre-concentration function comprises a mixing and stirring tank, a water inlet area is arranged on one side of the mixing and stirring tank, a water outlet area is arranged on the side, away from the water inlet area, of the mixing and stirring tank, the interior of the mixing and stirring tank is divided into a filtrate area and a coagulation and stirring area through a filtrate area side plate and a filtrate area bottom plate, and a communication opening is formed between the water inlet area and the coagulation and stirring area. The filtrate area is located at the upper part of the mixing and stirring tank, a plurality of filtering holes are formed in a side plate of the filtrate area, a stirring shaft is arranged in the coagulation and stirring area, a bracket is arranged on the stirring shaft, a brush cylinder is vertically arranged on the bracket, a clear water outlet is formed in the filtrate area, a mud outlet is formed in the water outlet area, a water inlet is