Influencing Factors of the Anaerobic Phosphorus Release From Aerobic Activated Sludge in Low-Temperature A2/O Process
LI Jianzheng1, GUO Yaqiong1, HE Junguo1, JIN Yu1,2
1. State Key Laboratory of Urban Water Resource and Environment; School of Municipal and Environmental Engineering,Harbin Institute of Technology, Harbin 150090, China;2. School of Resources & Environment, Northeast Agricultural University, Harbin 150030, China
Abstract：To enhance the phosphorus removal in the low-temperature A2/O wastewater treatment process, an anaerobic phosphorus release tank is attached to the aerobic treating process, and the control parameters of the tank are analyzed. The results show that the anaerobic phosphorus release of aerobic activated sludge from the secondary clarifier effectively improves the TP removal efficiency of the low-temperature A2/O process, and the COD removal is at the same time enhanced. In order to meet the demand for the carbon source of the anaerobic phosphorus release, raw water should be put into the anaerobic phosphorus release tank and mixed with the fresh sludge from the secondary clarifier in a volume ratio of 1:1, with a sludge load of 0.015-0.02g COD/g MLSS. For an sequencing batch process, the optimum sludge retention time is 14h, while in a continuous flow process it is 12h. NO3- would significantly inhibit the anaerobic phosphorus release, so its concentration should be controlled within 5mg/L. The intermittent slow blend is suggested to improve the efficiency of anaerobic phosphorus release.
2011, Vol. 29 
