Integrated dual circulation oxidization ditch apparatus for municipal wastewater and treatment method

An integrated dual circulation oxidization ditch apparatus for municipal wastewater, comprising an anaerobic zone, an anoxic zone, an aerobic zone and a secondary sedimentation tank, the anoxic zone comprising a first anoxic zone and a second anoxic zone, the aerobic zone comprising a first aerobic zone and a second aerobic zone, and a reflux pump being arranged between the anoxic zone and the aerobic zone,

• wherein the secondary sedimentation tank is provided with a water outlet channel, a sludge outlet and emptying pipe, and a reflux channel, the water outlet channel is provided with a water outlet, a sludge reflux pipe is arranged between the reflux channel and the anaerobic zone, the water outlet channel and the reflux channel are arranged at two ends of an upper portion of the secondary sedimentation tank, and a bottom of the secondary sedimentation tank is provided with an emptying pipeline for sludge discharge or maintenance.