HRT对反硝化除磷的影响

novel process consisting of anaerobic - aerobic -anoxic- short time aeration units was proposed to achieve shortcut nitrification coupled with simultaneous denitrifying phosphorus removal. At ambient temperature(25℃)，The process could be start-up quickly when its solids-retention time（SRT） was 20d、inffluent pH above 8.5、aerobic unit dissolved oxygen（DO）was above 3mg.L-1. When the process was stablly operated，the DO of aerobic 1 unit was 1.5~2.5 mg.L-1，the DO of aerobic 2 unit was 0.5~1 mg.L-1，its could realize stable nitrite accumulation，the nitrite concentration of aerobic 2 unit was above 5mg.L-1 and ammonia nitrogen removal efficiency was above 80%.When the Hydraulic retention time（SRT）was 9h，the process could achieve best effect for nitrite accumulation and denitrifying dephosphatation.