Nitrogen removal and microbial community characteristics of CANON process enhanced by static magnetic field at ambient temperature

An upflow anaerobic biofilter (AF) was developed to investigate anaerobic ammonium-oxidizing (ANAMMOX) efficiency in treating low-strength wastewater at ambient temperature (15.3–23.2 °C). Denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization were used to investigate treatment effects on the microbial community. Stepwise decreases in influent ammonia concentration could help ANAMMOX bacteria selectively acclimate to low-ammonia conditions. With an influent ammonia concentration of 46.5 mg/L, the AF reactor obtained an average nitrogen removal rate of 2.26 kg/(m3 day), and a removal efficiency of 75.9%. polymerase chain reaction-DGGE results showed that microbial diversity in the low matrix was greater than in the high matrix. Microbial community structures changed when the influent ammonia concentration decreased. The genus of functional ANAMMOX bacteria was Candidatus Kuenenia stuttgartiensis, which remained stationary across study phases. Visual observation revealed that the relative proportions of ANAMMOX bacteria decreased from 41.6 to 36.3% across three study phases. The AF bioreactor successfully maintained high activity due to the ANAMMOX bacteria adaptation to low temperature and substrate conditions.

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Performance and microbial community of the CANON process in a sequencing batch membrane bioreactor with elevated COD/N ratios

Water Science & Technology ◽

10.2166/wst.2020.089 ◽

2020 ◽

Vol 81 (1) ◽

pp. 138-147

Author(s):

Xiaoling Zhang ◽

Xincong Liu ◽

Meng Zhang

Keyword(s):

Organic Matter ◽

Microbial Community ◽

Nitrogen Removal ◽

Membrane Bioreactor ◽

Ammonia Oxidation ◽

Heterotrophic Bacteria ◽

Removal Rate ◽

Ammonia Oxidizing Bacteria ◽

Anaerobic Ammonia Oxidation ◽

Canon Process

Abstract In this study, the effects of elevated chemical oxygen demand/nitrogen (COD/N) ratios on nitrogen removal, production and composition of the extracellular polymer substances (EPS) and microbial community of a completely autotrophic nitrogen removal via nitrite (CANON) process were studied in a sequencing batch membrane bioreactor (SBMBR). The whole experiment was divided into two stages: the CANON stage (without organic matter in influent) and the simultaneous partial nitrification, anaerobic ammonia oxidation and denitrification (SNAD) stage (with organic matter in influent). When the inflow ammonia nitrogen was 420 mg/L and the COD/N ratio was no higher than 0.8, the addition of COD was helpful to the CANON process; the total nitrogen removal efficiency (TNE) was improved from approximately 65% to more than 75%, and the nitrogen removal rate (NRR) was improved from approximately 0.255 kgN/(m3·d) to approximately 0.278 kgN/(m3•d), while the TNE decreased to 60%, and the NRR decreased to 0.236 kgN/(m3•d) when the COD/N ratio was elevated to 1.0. For the EPS, the amounts of soluble EPS (SEPS) and loosely bound EPS (LB-EPS) were both higher in the CANON stage than in the SNAD stage, while the amount of tightly bound EPS (TB-EPS) in the SNAD stage was significantly higher due to the proliferation of heterotrophic bacteria. The metagenome sequencing technique was used to analyse the microbial community in the SBMBR. The results showed that the addition of COD altered the structure of the bacterial community in the SBMBR. The amounts of Candidatus ‘Anammoxoglobus’ of anaerobic ammonia oxidation bacteria (AAOB) and Nitrosomonas of ammonia oxidizing bacteria (AOB) both decreased significantly, and Nitrospira of nitrite oxidizing bacteria (NOB) was always in the reactor, although the amount changed slightly. A proliferation of denitrifiers related to the genera of Thauera, Dokdonella and Azospira was found in the SBMBR.

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Impact of increasing sulfide addition on the nitrogen removal and microbial community of CANON process in membrane bioreactor

Biochemical Engineering Journal ◽

10.1016/j.bej.2021.108071 ◽

2021 ◽

pp. 108071

Author(s):

Xiaojing Zhang ◽

Denghui Wei ◽

Zhao Chen ◽

Hongli Zhang ◽

Han Zhang ◽

...

Keyword(s):

Microbial Community ◽

Nitrogen Removal ◽

Membrane Bioreactor ◽

Canon Process

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Nitrogen Removal and N2O Accumulation during Hydrogenotrophic Denitrification: Influence of Environmental Factors and Microbial Community Characteristics

Environmental Science & Technology ◽

10.1021/acs.est.6b00071 ◽

2016 ◽

Vol 51 (2) ◽

pp. 870-879 ◽

Cited By ~ 48

Author(s):

Peng Li ◽

Yajiao Wang ◽

Jiane Zuo ◽

Rui Wang ◽

Jian Zhao ◽

...

Keyword(s):

Microbial Community ◽

Environmental Factors ◽

Nitrogen Removal ◽

Community Characteristics

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Response and Adaptation of Microbial Community in a CANON Reactor Exposed to an Extreme Alkaline Shock

Archaea ◽

10.1155/2020/8888615 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

Ruili Yang ◽

Wenlong Mao ◽

Xiaojun Wang ◽

Zhaoji Zhang ◽

Junbin Wu ◽

...

Keyword(s):

Microbial Community ◽

Influencing Factors ◽

Relative Abundance ◽

Nitrogen Removal ◽

Extracellular Polymeric Substances ◽

Recovery Phase ◽

Nitrogen Loading ◽

Anammox Bacteria ◽

Anammox Activity ◽

Canon Process

Responses of a microbial community in the completely autotrophic nitrogen removal over nitrite (CANON) process, which was shocked by a pH of 11.0 for 12 h, were investigated. During the recovery phase, the performance, anaerobic ammonia oxidation (anammox) activity, microbial community, and correlation of bacteria as well as the influencing factors were evaluated synchronously. The performance of the CANON process deteriorated rapidly with a nitrogen removal rate (NRR) of 0.13 kg·m-3·d-1, and Firmicutes, spore-forming bacteria, were the dominant phyla after alkaline shock. However, it could self-restore within 107 days after undergoing four stages, at which Planctomycetes became dominant with a relative abundance of 64.62%. Network analysis showed that anammox bacteria (Candidatus Jettenia, Kuenenia, and Brocadia) were positively related to some functional bacteria such as Nitrosomonas, SM1A02, and Calorithrix. Canonical correspondence analysis presented a strong correlation between the microbial community and influencing factors during the recovery phase. With the increase of nitrogen loading rate, the decrease of free nitrous acid and the synergistic effects, heme c content, specific anammox activity (SAA), NRR, and the abundance of dominant genus increased correspondingly. The increase of heme c content regulates the quorum sensing system, promotes the secretion of extracellular polymeric substances, and further improves SAA, NRR, and the relative abundance of the dominant genus. This study highlights some implications for the recovery of the CANON reactor after being exposed to an alkaline shock.

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