Autotrophic nitrogen removal at low temperature

In this work the autotrophic nitrogen removal was carried out at moderately low temperatures using two configurations: a) two-units one comprising a SHARON reactor coupled to an Anammox SBR and b) single-unit one consisting of a granular SBR performing the CANON process. At 20°C the two-units system was limited by the Anammox step and its nitrogen removal capacity was around ten times lower than the CANON system (0.08 g N/(L d) versus 1 g N/(L d)). When the CANON system was operated at 15°C the average removed nitrogen loading rate decreased to 0.2 g N/(L d). The CANON system was operated in order to limit the ammonia oxidation rate to avoid nitrite inhibition of Anammox bacteria. Since both, temperature and dissolved oxygen (DO) concentration regulate ammonia oxidizing bacteria activity, once the temperature of the reactor is decreased the DO concentration must be decreased to avoid the deeper oxygen penetration inside the granule which could cause inhibition of Anammox bacteria by oxygen and/or nitrite.

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Start-Up and Aeration Strategies for a Completely Autotrophic Nitrogen Removal Process in an SBR

BioMed Research International ◽

10.1155/2017/1089696 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Xiaoling Zhang ◽

Fan Zhang ◽

Yanhong Zhao ◽

Zhengqun Li

Keyword(s):

Removal Efficiency ◽

Total Nitrogen ◽

Nitrogen Removal ◽

Tap Water ◽

Granular Sludge ◽

Anammox Bacteria ◽

Intermittent Aeration ◽

Start Up ◽

Canon Process ◽

Autotrophic Nitrogen Removal

The start-up and performance of the completely autotrophic nitrogen removal via nitrite (CANON) process were examined in a sequencing batch reactor (SBR) with intermittent aeration. Initially, partial nitrification was established, and then the DO concentration was lowered further, surplus water in the SBR with high nitrite was replaced with tap water, and continuous aeration mode was turned into intermittent aeration mode, while the removal of total nitrogen was still weak. However, the total nitrogen (TN) removal efficiency and nitrogen removal loading reached 83.07% and 0.422 kgN/(m3·d), respectively, 14 days after inoculating 0.15 g of CANON biofilm biomass into the SBR. The aggregates formed in SBR were the mixture of activated sludge and granular sludge; the volume ratio of floc and granular sludge was 7 : 3. DNA analysis showed that Planctomycetes-like anammox bacteria and Nitrosomonas-like aerobic ammonium oxidization bacteria were dominant bacteria in the reactor. The influence of aeration strategies on CANON process was investigated using batch tests. The result showed that the strategy of alternating aeration (1 h) and nonaeration (1 h) was optimum, which can obtain almost the same TN removal efficiency as continuous aeration while reducing the energy consumption, inhibiting the activity of NOB, and enhancing the activity of AAOB.

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Nitrogen removal via a single-stage PN–Anammox process in a novel combined biofilm reactor

Water Science & Technology ◽

10.2166/wst.2017.572 ◽

2017 ◽

Vol 77 (6) ◽

pp. 1483-1492 ◽

Cited By ~ 6

Author(s):

Yue-mei Han ◽

Feng-xia Liu ◽

Xiao-fei Xu ◽

Zhuo Yan ◽

Zhi-jun Liu

Keyword(s):

Total Nitrogen ◽

Nitrogen Removal ◽

Ammonia Oxidation ◽

Biofilm Reactor ◽

Nitrifying Bacteria ◽

Anammox Bacteria ◽

Ammonia Oxidizing Bacteria ◽

High Ammonia ◽

Total Nitrogen Removal ◽

Anammox Process

Abstract This study developed a partial nitrification (PN) and anaerobic ammonia oxidation (Anammox) process for treating high-ammonia wastewater using an innovative biofilm system in which ammonia oxidizing bacteria grew on fluidized Kaldnes (K1) carriers and Anammox bacteria grew on fixed acryl resin carriers. The airlift loop biofilm reactor (ALBR) was stably operated for more than 4 months under the following conditions: 35 ± 2 °C, pH 7.5–8.0 and dissolved oxygen (DO) of 0.5–3.5 mg/L. The results showed that the total nitrogen removal efficiency reached a maximum of 75% and the total nitrogen removal loading rate was above 0.4 kg/(d·m3). DO was the most efficient control parameter in the mixed biofilm system, and values below 1.5 mg/L were observed in the riser zone for the PN reaction, while values below 0.8 mg/L were observed in the downer zone for the Anammox reaction. Scanning electron microscopy and Fluorescence In Situ Hybridization images showed that most of the nitrifying bacteria were distributed on the K1 carriers and most of the Anammox bacteria were distributed within the acryl resin carriers. Therefore, the results indicate that the proposed combined biofilm system is easy to operate and efficient for the treatment of high-ammonia wastewater.

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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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Nitrogen removal and microbial communities of a completely autotrophic nitrogen removal over nitrite (CANON) sequencing batch biofilm reactor (SBBR) at different inorganic carbon (IC) concentrations

Water Science & Technology ◽

10.2166/wst.2020.203 ◽

2020 ◽

Vol 81 (5) ◽

pp. 1071-1079

Author(s):

Caimeng Wang ◽

Lirong Lei ◽

Fangrui Cai ◽

Youming Li

Keyword(s):

Nitrogen Removal ◽

Inorganic Nitrogen ◽

Biofilm Reactor ◽

Anammox Bacteria ◽

Ammonium Oxidation ◽

Sequencing Batch Biofilm Reactor ◽

Microbial Analysis ◽

Total Inorganic Nitrogen ◽

Canon Process ◽

Autotrophic Nitrogen Removal

Abstract In this study, the completely autotrophic nitrogen removal over nitrite (CANON) process was initiated in a sequencing batch biofilm reactor (SBBR). Then the reactor was operated under different IC/N ratios. The total inorganic nitrogen removal efficiency (TINRE) at IC/N ratios of 0.75, 1.0, 1.25, 1.5 and 2.0 were 37.0 ± 11.0%, 58.9 ± 10.2%, 73.9 ± 3.2%, 73.6 ± 1.8% and 72.6 ± 2.0%, respectively. The suitable range of IC/N ratio in this research is 1.25–2.0. The poor nitrogen removal performance at IC/N ratio of 0.75 was due to the lack of growth substrate for AnAOB and low pH simultaneously; at IC/N ratio of 1.0 this was because the substrate concentration was insufficient for fully recovering the AnAOB activities. Microbial analysis indicated that Nitrosomonas, Nitrospira and Candidatus Brocadia were the main ammonium oxidation bacteria (AOB), nitrite oxidation bacteria (NOB) and anammox bacteria (AnAOB), respectively. In addition, at IC ratios of 1.25 or higher, denitrification was promoted with the rise of IC/N ratio, which might be because the change of IC concentrations caused cell lysis of microorganisms and provided organic matter for denitrification.

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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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Performance and microbial community of the completely autotrophic nitrogen removal over nitrite process with a submerged aerated biological filter

Water Science & Technology ◽

10.2166/wst.2018.316 ◽

2018 ◽

Vol 78 (3) ◽

pp. 515-522 ◽

Cited By ~ 1

Author(s):

Xiu Yue ◽

Zhuhan Liu ◽

Guangping Yu ◽

Qianhua Li ◽

Jiali Tang

Keyword(s):

Nitrogen Removal ◽

Technical Problem ◽

Rrna Gene ◽

Ammonia Oxidizing Bacteria ◽

Biological Filter ◽

Working Volume ◽

Stable Performance ◽

Removal Efficiencies ◽

Canon Process ◽

Autotrophic Nitrogen Removal

Abstract Stable performance is a technical problem in the completely autotrophic nitrogen removal over nitrite (CANON) process with one single stage, which needs to be addressed. In the current work, a laboratory-scale submerged aerated biological filter (SABF) with a 3-L working volume was introduced into the CANON process to enhance its stable performance for 290 days under the following conditions: temperature of 30 ± 1 °C and dissolved oxygen (DO) level of 0.2–0.8 mg·L−1. The results showed that the average ammonium nitrogen removal efficiencies (ANRE) and total nitrogen removal efficiencies (TNRE) were 97.4% and 75.7%, respectively. A 16S rRNA gene high-throughput sequencing technology confirmed the phyla Proteobacteria and Planctomycetes as the ammonium oxidizing bacteria (AOB) and anaerobic ammonia-oxidizing bacteria (AnAOB) of this CANON process with SABF, respectively. The major contributor to nitrogen removal was the genus Candidatus Brocadia, in Brocadiae. The aim is to present an effective strategy as a reference for the design of full-scale plant for the CANON process.

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Overlooked nitrogen-cycling microorganisms in biological wastewater treatment

Frontiers of Environmental Science & Engineering ◽

10.1007/s11783-021-1426-2 ◽

2021 ◽

Vol 15 (6) ◽

Author(s):

Shaoyi Xu ◽

Xiaolong Wu ◽

Huijie Lu

Keyword(s):

Wastewater Treatment ◽

Nitrogen Cycling ◽

Nitrogen Removal ◽

Ammonia Oxidation ◽

Current Knowledge ◽

N Cycling ◽

Anammox Bacteria ◽

Kinetic Properties ◽

Ammonia Oxidizing Bacteria ◽

Removal Processes

AbstractNitrogen-cycling microorganisms play key roles at the intersection of microbiology and wastewater engineering. In addition to the well-studied ammonia oxidizing bacteria, nitrite oxidizing bacteria, heterotrophic denitrifiers, and anammox bacteria, there are some other N-cycling microorganisms that are less abundant but functionally important in wastewater nitrogen removal. These microbes include, but not limited to ammonia oxidizing archaea (AOA), complete ammonia oxidation (comammox) bacteria, dissimilatory nitrate reduction to ammonia (DNRA) bacteria, and nitrate/nitrite-dependent anaerobic methane oxidizing (NOx-DAMO) microorganisms. In the past decade, the development of high-throughput molecular technologies has enabled the detection, quantification, and characterization of these minor populations. The aim of this review is therefore to synthesize the current knowledge on the distribution, ecological niche, and kinetic properties of these “overlooked” N-cycling microbes at wastewater treatment plants. Their potential applications in novel wastewater nitrogen removal processes are also discussed. A comprehensive understanding of these overlooked N-cycling microbes from microbiology, ecology, and engineering perspectives will facilitate the design and operation of more efficient and sustainable biological nitrogen removal processes.

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Performance and inhibition recovery of anammox reactors seeded with different types of sludge

Water Science & Technology ◽

10.2166/wst.2011.293 ◽

2011 ◽

Vol 63 (4) ◽

pp. 710-718 ◽

Cited By ~ 10

Author(s):

S. Q. Ni ◽

J. Meng

Keyword(s):

Nitrogen Removal ◽

Granular Sludge ◽

Recovery Process ◽

Nitrogen Loading ◽

Anaerobic Sludge ◽

Anammox Bacteria ◽

Recovery Processes ◽

Anammox Activity ◽

Different Types ◽

Anaerobic Sludge Blanket

In order to study the performance, inhibition and recovery processes of different types of anammox sludge, three up-flow anaerobic sludge blanket reactors were inoculated with flocculent sludge, granular sludge, and cultured inactive methanogenic granules. During stable period, with nitrogen loading rates of 0.9–1.1 kg/m3/d, the total nitrogen removal efficiencies of these reactors averaged at 86.5%, 90.8% and 93.5%, respectively. The kinetics study indicated that the reactor seeded with cultured inactive methanogenic granules possessed the highest nitrogen removal potential, followed by the granular anammox reactor and the flocculent anammox reactor. The study suggested that a concentration as high as 988.3 mg NH4+-N/L and 484.4 mg NO2−-N/L could totally inhibit granular anammox bacteria and result in a inhibition of 50% flocculent anammox activity. In addition, reactors seeded with flocculent sludge and anammox granules could be fully recovered by decreasing their influent substrate concentrations. However, the decrease of influent substrate concentration for the reactor with cultured inactive methanogenic granules could only restore about 75% of its bacterial activity. In this study, anammox bacteria purity was the major factor to evaluate the recovery ability in comparison with sludge type. Free ammonia was a more appropriate indicator for the anammox recovery process compared to free nitric acid.

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Performance of the anammox sequencing batch reactor treating synthetic and real landfill leachate

E3S Web of Conferences ◽

10.1051/e3sconf/20184400179 ◽

2018 ◽

Vol 44 ◽

pp. 00179 ◽

Cited By ~ 1

Author(s):

Mariusz Tomaszewski ◽

Grzegorz Cema ◽

Tomasz Twardowski ◽

Aleksandra Ziembińska-Buczyńska

Keyword(s):

Nitrogen Removal ◽

Landfill Leachate ◽

Sequencing Batch Reactor ◽

Batch Reactor ◽

Nitrogen Loading ◽

Synthetic Wastewater ◽

High Nitrogen ◽

Removal Capacity ◽

Anammox Activity ◽

Anammox Process

The anaerobic ammonium oxidation (anammox) process is one of the most energy efficient and environmentally-friendly bioprocess for the treatment of the wastewater with high nitrogen concentration. The aim of this work was to study the influence of the high nitrogen loading rate (NLR) on the nitrogen removal in the laboratory-scale anammox sequencing batch reactor (SBR), during the shift from the synthetic wastewater to landfill leachate. In both cases with the increase of NLR from 0.5 to 1.1 – 1.2 kg N/m3d, the nitrogen removal rate (NRR) increases to about 1 kg N/m3d, but higher NLR caused substrates accumulation and affects anammox process efficiency. Maximum specific anammox activity was determined as 0.638 g N/g VSSd (NRR 1.023 kg N/m3d) and 0.594 g N/g VSSd (NRR 1.241 kg N/m3d) during synthetic and real wastewater treatment, respectively. Both values are similar and this is probably the nitrogen removal capacity of the used anammox biomass. This indicates, that landfill leachate did not influence the nitrogen removal capacity of the anammox process.

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454-Pyrosequencing Analysis of Bacterial Communities from Autotrophic Nitrogen Removal Bioreactors Utilizing Universal Primers: Effect of Annealing Temperature

BioMed Research International ◽

10.1155/2015/892013 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 11

Author(s):

Alejandro Gonzalez-Martinez ◽

Alejandro Rodriguez-Sanchez ◽

Belén Rodelas ◽

Ben A. Abbas ◽

Maria Victoria Martinez-Toledo ◽

...

Keyword(s):

Bacterial Diversity ◽

Nitrogen Removal ◽

Annealing Temperature ◽

16S Rrna Genes ◽

Rrna Genes ◽

Universal Primers ◽

Anammox Bacteria ◽

Universal Primer ◽

Optimum Annealing Temperature ◽

Autotrophic Nitrogen Removal

Identification of anaerobic ammonium oxidizing (anammox) bacteria by molecular tools aimed at the evaluation of bacterial diversity in autotrophic nitrogen removal systems is limited by the difficulty to design universal primers for theBacteriadomain able to amplify the anammox 16S rRNA genes. A metagenomic analysis (pyrosequencing) of total bacterial diversity including anammox population in five autotrophic nitrogen removal technologies, two bench-scale models (MBR and Low Temperature CANON) and three full-scale bioreactors (anammox, CANON, and DEMON), was successfully carried out by optimization of primer selection and PCR conditions (annealing temperature). The universal primer 530F was identified as the best candidate for total bacteria and anammox bacteria diversity coverage. Salt-adjusted optimum annealing temperature of primer 530F was calculated (47°C) and hence a range of annealing temperatures of 44–49°C was tested. Pyrosequencing data showed that annealing temperature of 45°C yielded the best results in terms of species richness and diversity for all bioreactors analyzed.

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