1. Comparing two hydrazine addition strategies to stabilize mainstream deammonification: Performance and microbial community analysis.
- Author
-
Xiang T and Gao D
- Subjects
- Ammonia metabolism, Betaproteobacteria drug effects, Nitrogen isolation & purification, Nitrosomonas drug effects, Sewage microbiology, Hydrazines pharmacology, Microbiota drug effects
- Abstract
In this study, an expanded granular sludge blanket reactor (EGSB) was proposed to achieve stable mainstream deammonification process by adding hydrazine (N
2 H4 ). Two N2 H4 addition methods consisted of constant concentration (strategy A) and variable concentration (strategy B) both can inhibit nitrite oxidizing bacteria. A efficient performance was achieved with higher total nitrogen removal efficiency (82 ± 6%) and nitrogen removal rate (0.32 ± 0.02 kg N/(m3 ·d)) under strategy B. For strategy A, anaerobic ammonia oxidizing bacteria (AnAOB) in-situ activity was decreased from 2.76 to 0.68 mg N/(g VSS·h) at 42 mg/L NH4 + -N. Candidatus Brocadia abundance increase from 14.62% to 20.07% under the strategy may indicated the self-regulate mechanism of AnAOB. Aerobic ammonia oxidizing bacteria (AOB, mainly Nitrosomonas) and AnAOB (mainly Candidatus Brocadia) were always dominated under two strategies. Strategy B provided better environment for most microorganisms (mainly Chloroflexri, Planctomycetes, Proteobacteria and Chlorobi)., (Copyright © 2019 Elsevier Ltd. All rights reserved.)- Published
- 2019
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