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Updated: Feb 5, 2026

Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading
Published on: March 6, 2014
[Characteristics of Denitrifying Phosphorus Removal by A2/O-BAF at Low Temperatures]
Jian-Ming Huang1, Zhi-Chao Zhao1, Long-Ju Zheng2
1School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China.
Abstract:
Low C/N domestic sewage was treated by an A2/O-biological aerated filter (BAF) system at low temperatures (11-14℃). The characteristics of pollutant removal, the ratio of denitrifying phosphorus to nitrogen (ΔPO43-/ΔNO3-N) and effects of aeration flow and effective packing height on nitrification in BAF were studied. The results showed that when the average influent concentrations of COD, NH4+-N, TN and PO43- were 193.1, 58.6, 60.3 and 5.1 mg·L-1 respectively, their effluent concentrations were 46.3, 2.5, 13.4 and 0.3 mg·L-1 respectively, which met the first level A criteria specified in the discharge standard of pollutants for municipal wastewater treatment plant (GB 18918-2002). The linear fitting of ΔPO43-/ΔNO3--N was between 0.47 and 1.75. The normal distribution of mathematical statistics was applied-and the average standard deviation for ΔPO43-/ΔNO3--N were 1.20 and 0.29 respectively. When the aeration flows were 60 L·h-1 and 100 L·h-1, the effluent concentration of NH4+-N was less than 5.0 mg·L-1, corresponding to the effective packing heights in the BAF of 1.8 m and 1.0 m respectively. However, when the aeration flow was increased to 120 L·h-1, the air-water flow led to biofilm detachment, which caused the effluent concentration of NH4+-N to increase beyond 5.0 mg·L-1.
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