Effect of Step Feed on Denitrifying Phosphorus and Nitrate Removal in a Modification of the Two Sludge A 2 /O-BAF System

• Published in: Huanjing kexue Vol. 39; no. 4; p. 1704
• Main Authors: Nan, Yan-Bin, Peng, Yong-Zhen, Zeng, Li-Yun, Zhao, Zhi-Chao, Liu, Hong, Li, Hui, Chen, Yong-Zhi
• Format: Journal Article
• Language: Chinese
• Published: China 08.04.2018
• Subjects: Bioreactors - microbiology; Denitrification; Nitrates - isolation & purification; Nitrogen; Phosphorus - chemistry; Sewage; Waste Disposal, Fluid - methods; denitrifying phosphorus and nitrate removal; low C/N; ratio of step feed; material balance; utilization of carbon sources
• ISSN: 0250-3301

A modification of the two sludge A /O-BAF system was used to treat low C/N real domestic sewage. In order to improve the utilization of the carbon source, the effects of two step feeds (pre-anoxic zone and anoxic zone) on denitrifying phosphorus and nitrate removal were studied. According to the formula of material balance for COD, the utilization of carbon source was analyzed and evaluated under different ratios of step feed, simultaneously. The results showed that when the ratio of step feed was 7:3 and the influent concentrations of COD, NH -N, TN, and TP were 174.99, 58.19, 59.10, and 5.15 mg·L , respectively, their effluent concentrations were 29.48, 4.07, 14.10, and 0.40 mg·L , and the removal rates were 82.12%, 92.76%, 75.45%, and 91.20%, respectively. It was found that when the ratio of the denitrifying phosphorus accumulation organisms to the phosphorus accumulation organisms(DPAOs/PAOs) was 98.81%, the efficiencies of denitrifying phosphorus and nitrate removal were optimum. By optimizing step feed,