Multi-effect sedimentation tank

The invention discloses a multi-effect sedimentation tank, which comprises two unilateral sedimentation tank main bodies, the two unilateral sedimentation tank main bodies are distributed in a bilateral symmetry rectangle, the two unilateral sedimentation tanks are symmetrically communicated with each other, and the two unilateral sedimentation tanks share the same biological treatment tank and the same water collection main tank. The multiple-effect sedimentation tank integrates multiple functions such as sewage degassing, sludge coagulation, inclined tube sedimentation, vertical flow sedimentation, horizontal flow sedimentation, circumferential inlet and circumferential outlet radial flow sedimentation, circumferential inlet and middle outlet radial flow sedimentation and the like, sludge in sewage can be subjected to coagulation reaction at different parts in the multiple-effect sedimentation tank, the sedimentation performance of the sludge is improved, sedimentation in different modes is carried out, and