Prof. Zhan’s research group has published a paper on Start up of partial nitritation-anammox process using intermittently aerated sequencing batch reactor: performance and microbial community dynamics. This research is co-funded by the Irish Department of Agriculture, Food and the Marine for the DairyWater project (Ref.: 13-F-507) and China Scholarship Council.
In his research, he investigated the performance and microbial community dynamics in an intermittently aerated sequencing batch reactor (IASBR) when he developed a new start-up method for the partial nitritation-anammox (PN-A) process. The robustness of this PN-A IASBR system in achieving long-term efficient nitrogen removal was also investigated. Stable partial nitritation with a nitrite accumulation ratio of about 80% was firstly achieved in the IASBR. Then, PN-A process with total nitrogen removal of up to 81.5% was established due to the thriving of anammox bacteria Candidatus Kuenenia resulting from the reduction of the aeration rate. Molecular analysis showed that both bacterial and archaeal communities shifted greatly throughout the start-up stage and the PN-A stage. Besides bacterial genus Nitrosomonas, ammonium-oxidizing archaea (AOA) Candidatus Nitrososphaera with a high abundance of 3.44% also contributed to partial nitritation. Nitrospira was effectively restrained (abundance <1.6%) while methanogens co-existed with the aerobic and anaerobic nitrogen-conversion microorganisms. This study showed that IASBR configuration was efficient in starting up the PN-A process from return sludge, maintaining long-term efficient nitrogen removal and triggering the thrive of AOA.
The full paper is found at: Start-up of partial nitritation-anammox process using intermittently aerated sequencing batch reactor: Performance and microbial community dynamics. Science of Total Environment, 647, 1188-1198, 2019 (authors: Songkai Qiu, Yuansheng Hu, Rui Liu, Xiaolin Sheng, Lvjun Chen, Guangxue Wu, Hongying Hu, Xinmin Zhan)