Double running mode biological dephosphorizing and denitrifying sewage treater

The utility model relates to a bimodality operating sewage treatment equipment for the biology phosphorous and nitrogen removal, comprising an anaerobic tank (1), an anoxic tank (2), an aerobic tank (3), a distributing reservoir (4), a mud distributing reservoir (5), a plurality of valves (Z1, Z2, Z3, Z4, Z5, Z6, Z7); wherein, the distributing tank (4) is respectively communicated with the anaerobic tank (1), the mud distributing reservoir (5) and the anoxic tank (2) via the valves (Z1, Z2, Z3) and the water pore A1, A3. The distributing reservoir (4) is communicated with mud distributing reservoir (5) via the valve (Z2). The mud distributing reservoir (5) is communicated with the anoxic tank (2) via the valve (Z4). The anaerobic tank (1) is communicated with the aerobic tank (3) via the valve (Z5). The anoxic tank (2) is communicated with the aerobic tank (3) respectively via the valves (Z6, Z7). The anaerobic tank (1) and the anoxic tank (2) are communicated with each other via the water pore A2. The anoxic tank (2) is communicated with a peripheral sedimentation tank via the water pore A4. The utility model has the advantages of switching flexibly according to the different water qualities and different process requirements, and operating in different modes, so as to reach the target of reducing the energy consumption.