Simultaneous nitrogen and phosphorus removal under low dissolved oxygen conditions

Article type: Research Article

Authors: Xia, Si-qing | Gao, Ting-yao | Zhou, Zeng-yuan

Affiliations: School of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. E-mail: [email protected]

Abstract: A full-scale test was operated by using low dissolved oxygen activated sludge process to enhance biological nitrogen and phosphorus removal. When the influent concentrations of COD_Cr, TN and TP varied in a range of 352.9 mg/L-1338.2 mg/L, 34.4 mg/L-96.3 mg/L, and 2.21 mg/L-24.0 mg/L, the average removal efficiencies were 94.9%, 86.7% and 93.0%, respectively. During the test period of two months, effluent meas of COD_Cr, BOD_5, NH_3-N, TN and TP were below 50 mg/L, 25 mg/L, 10 mg/L and 1.0 mg/L, respectively. The low dissolved oxygen activated sludge process has a simple flow sheet, fewer facilities and high N and P removal efficiency. It is very convenient to retrofit the conventional activated sludge process with the above process.

Keywords: high concentration activated sludge, low dissolved oxygen process, phosphorus removal, nitrogen removal

Journal: Journal of Environmental Sciences, vol. 13, no. 1, pp. 46-50, 2001