Yan Guo, Eli Hendrik Sanjaya, Tianjie Wang, Chao Rong, Zibin Luo, Yi Xue, Hong Chen, Yu-You Li
The phosphorus harvest along nitrogen removal in the partial nitritation/anammox (PNA) reactor is promising for saving space and simplifying the management of mainstream wastewater treatment facilities. In this study, the phosphorus recovery from the low-temperature mainstream wastewater was explored through iron phosphate crystallization in a pilot-scale PNA reactor. With the COD-alleviated municipal wastewater as the influent, the ammonium concentration of about 50 mg/L and the phosphorus concentration ranged from 5.4 to 7.1 mg/L, under the temperature of 15 °C and the addition of external ferrous iron of 14 mg/L, the achieved nitrogen removal efficiency and the phosphorus removal efficiency were 37.6 % and 62.7 %, respectively. The good settleability of sludge indicated that the formed iron phosphate was well combined with the biomass. The quantitative analysis confirmed that the main iron phosphate in dry sludge was graftonite, and qualitative analysis confirmed that the equivalent of P2O5 content in the sludge was 5.8 %, which was suitable as fertilizer on agricultural land to realize the direct recycle of discharged phosphorus. In all, this study proposed a pioneering scheme to realize the nitrogen removal and phosphorus cycle in human society and given a meaningful reference for further research and application. © 2022
Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aramaki Aza Aoba, Aoba-ku, Miyagi, Sendai, 980-8579, Japan; Department of Chemistry, State University of Malang (Universitas Negeri Malang), Jl. Semarang No. 5, East Java, Malang, 65145, Indonesia; Graduate School of Environmental Studies, Tohoku University, 6-6-06 Aramaki Aza Aoba, Aoba-ku, Miyagi, Sendai, 980-8579, Japan; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha University of Science & Technology, Changsha, 410004, China