Nitrogen removal performance of marine anammox bacteria treating nitrogen-rich saline wastewater under different inorganic carbon doses: High inorganic carbon tolerance and carbonate crystal formation

With nitrite or nitrate nitrogen as electron acceptor in the high salt conditons, halophilic denitrifying bacteria can transfer nitrite or nitrate to nitrogen, thereby purifying the high-salt wastewater. Halophilic denitrifying bacteria play an important role in the carbon and nitrogen removal of saline wastewater, such as petroleum, chemical industry, seafood processing and seafood farming. This article dissussed halophilic denitrifying bacteria screening, the main types and the corresponding morphological characteristics, then we focused on the research progress of main factors of halophilic denitrifying bacteria’s growth and nitrogen removal. Finally put forward the current problems of the research and development trend of halophilic denitrifying bacteria.

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Temperature modulates stress response in anammox reactors

10.1101/2020.02.17.952358 ◽

2020 ◽

Author(s):

Robert Niederdorfer ◽

Damian Hausherr ◽

Alejandro Palomo ◽

Jing Wei ◽

Paul Magyar ◽

...

Keyword(s):

Stress Response ◽

Dissolved Oxygen ◽

Nitrogen Removal ◽

High Stress ◽

Anammox Bacteria ◽

Transcriptional Responses ◽

Microbial Biofilms ◽

Temperature Regimes ◽

Anammox Activity ◽

Stress Susceptibility

AbstractAutotrophic nitrogen removal by anaerobic ammonium oxidizing (anammox) bacteria is an energy-efficient nitrogen removal process in wastewater treatment. However, full-scale deployment under mainstream conditions remains challenging for practitioners due to the high stress susceptibility of anammox bacteria towards fluctuations in dissolved oxygen and temperature. Here, we investigated the response of microbial biofilms with verified anammox activity to oxygen shocks under favorable and cold temperature regimes. Genome-centric metagenomics and metatranscriptomics were used to investigate the stress response on various biological levels. We show that temperature regime and strength of oxygen perturbations induced divergent responses from the process level down to the transcriptional profile of individual taxa. Temperature induced distinct transcriptional states in compositionally identical communities and transient pulses of dissolved oxygen resulted in the upregulation of stress-response only under favorable temperatures. Anammox species and other key biofilm taxa display different transcriptional responses to the induced stress regimes.

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Enhanced Nitrogen Removal from Domestic Wastewater by Partial-Denitrification/Anammox in an Anoxic/Oxic Biofilm Reactor

Processes ◽

10.3390/pr10010109 ◽

2022 ◽

Vol 10 (1) ◽

pp. 109

Author(s):

Yu Huang ◽

Yongzhen Peng ◽

Donghui Huang ◽

Jiarui Fan ◽

Rui Du

Keyword(s):

Nitrogen Removal ◽

Oxygen Demand ◽

Domestic Wastewater ◽

Biofilm Reactor ◽

Anammox Bacteria ◽

Stable Operation ◽

Ammonium Oxidation ◽

N Accumulation ◽

Carbon Demand ◽

Oxidation Efficiency

A partial-denitrification coupling with anaerobic ammonium oxidation (anammox) process (PD/A) in a continuous-flow anoxic/oxic (A/O) biofilm reactor was developed to treat carbon-limited domestic wastewater (ammonia (NH4+-N) of 55 mg/L and chemical oxygen demand (COD) of 148 mg/L in average) for about 200 days operation. Satisfactory NH4+-N oxidation efficiency above 95% was achieved with rapid biofilm formation in the aerobic zone. Notably, nitrite (NO2−-N) accumulation was observed in the anoxic zone, mainly due to the insufficient electron donor for complete nitrate (NO3−-N) reduction. The nitrate-to-nitrite transformation ratio (NTR) achieved was as high as 64.4%. After the inoculation of anammox-enriched sludge to anoxic zones, total nitrogen (TN) removal was significantly improved from 37.3% to 78.0%. Anammox bacteria were effectively retained in anoxic biofilm utilizing NO2−-N produced via the PD approach and NH4+-N in domestic wastewater, with the relative abundance of 5.83% for stable operation. Anammox pathway contributed to TN removal by a high level of 38%. Overall, this study provided a promising method for mainstream nitrogen removal with low energy consumption and organic carbon demand.

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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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