Sewage treatment system and method of continuous flow step-feed short-cut denitrification-anaerobic ammonia oxidation coupled with denitrification

A sewage treatment system of continuous flow step-feed short-cut denitrification-anaerobic ammonia oxidation coupled with denitrification, characterized in that, the system includes a primary sedimentation tank, a bioreactor and a secondary sedimentation tank, which are connected in sequence;

• the bioreactor includes a pre-starvation zone, a first hypoxic zone, a first aerobic zone, a second hypoxic zone, and a second aerobic zone;
• the pre-starvation zone, the first hypoxic zone, the first aerobic zone, the second hypoxic zone and the second aerobic zone are sequentially connected through a partition plate with through-holes at an upper part;
• the pre-starvation zone, the first hypoxic zone and the second hypoxic zone are all arranged with agitators inside;
• both the first aerobic zone and the second aerobic zone are arranged with aeration devices inside, the aeration devices are connected to an air pump located outside the bioreactor, and the air pump is used to provide dissolved oxygen to the system;
• both the first hypoxic zone and the second hypoxic zone are arranged with polyurethane sponge fillers inside;
• a nitrification liquid reflux pump is arranged between the first aerobic zone and the pre-starvation zone;
• the primary sedimentation tank is respectively connected to the second hypoxic zone and the first hypoxic zone of the bioreactor through a first water inlet pump and a second water inlet pump;
• a water inlet end of the secondary sedimentation tank is connected to the second aerobic zone;
• a bottom of the secondary sedimentation tank is connected to the pre-starvation zone through a sludge reflux pump;
• the system also includes a PLC control subsystem, and the PLC control subsystem is used to realize chain reaction control of the system.