Enzhe Yang, Jing Chen, Ziyi Jiang, Zhengyu Deng, Zhi Tu, Hong Wang, Sha Wu, Zhe Kong, Eli Hendrik Sanjaya, Hong Chen
Partial nitritation-anammox (PNA) deteriorates easily and is difficult to recover. After an airlift inner-circulation partition bioreactor was impacted by low NH4+–N wastewater containing organic matter, Nitrospira and Denitratisoma propagated rapidly, granular sludge disintegrated, and the total nitrogen removal efficiency (TNRE) decreased from 68.27 % to 5.97 %. This study used a unique strategy to recover deteriorated single-stage PNA systems and explored the mechanism of rapid performance recovery. The TNRE of the system recovered up to 61.77 % in 43 days. The high nitrogen loading rate and hydraulic shear force from the airlift caused the sludge in the reactor to granulate again. The microbial community structure recovered, with a decrease in the abundance of Nitrospira (0.05 %) and enrichment of Candidatus Brocadia (8.82 %). A favorable synergy among functional microbes in the reactor was thus re-established, promoting the rapid recovery of the nitrogen removal performance. This study provides a feasible recovery strategy for PNA processes. © 2022 Elsevier Ltd
School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha, 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha, 410114, China; China Machinery International Engineering Design & Research Institute Co., Ltd, Changsha, 410007, China; State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China; Chemistry Department, Universitas Negeri Malang, 65145, Indonesia