Switchable two-stage AO denitrification nitrogen removal integrated reaction device

The utility model discloses a switchable two-stage AO denitrification nitrogen removal integrated reaction device, which comprises an aerobic tank, a first sedimentation tank, a first anoxic tank, a second sedimentation tank, a second anoxic tank and a sludge tank, the aerobic tank is arranged on the top of a first support frame, the first sedimentation tank is arranged on the top of a third support frame, and the second sedimentation tank is arranged on the top of a third support frame. According to the device, the aerobic tank, the sedimentation tank and the anoxic tank are arranged in a stepped form under the action of gravity, and the flowing of liquid is controlled through the electromagnetic valve, so that the requirement of a centrifugal pump is reduced, the denitrification cost is reduced, and the device can realize split-flow denitrification treatment on sewage with the same volume, so that the denitrification effect is improved; according to the present invention, with the two anoxic tanks, the seri