Anammox bacteria enrich naturally in suspended sludge system during partial nitrification of domestic sewage and contribute to nitrogen removal

ABSTRACT Reliable tools for quantification of different functional populations are required to achieve stable, effective nutrients removal in partial nitrification and anammox (PN/A) processes. Here we report the design and validation of degenerate PCR primer pairs targeting anammox bacteria, aerobic ammonium-oxidizing bacteria (AeAOB) and nitrite-oxidizing bacteria (NOB) with high coverage but without sacrificing specificity. The new primer pairs are able to cover a broader range of the targeted populations (58.4 vs 21.7%, 49.5 vs 47.6%, 80.7 vs 57.2% and 70.5 vs 42.3% of anammox bacteria, AeAOB, Nitrobacter and Nitrospina, respectively) than previously published primers. Particularly, the Amx719F/875R primer can retrieve a larger number of 16S rRNA genes from different types of samples with amplicons covering all known anammox bacteria genera (100% coverage) including the recently found novel genus, Asahi BRW. These newly desinged primers will provide a more reliable molecular tool to investigate the mechanisms of nitrogen removal in PN/A processes, which can provide clearer links between reactor performance, the metabolic activities and abundances of functional populations, shedding light on conditions that are favorable to the establishment of stable PN/A.

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Effects of carbon sources, COD/NO2−-N ratios and temperature on the nitrogen removal performance of the simultaneous partial nitrification, anammox and denitrification (SNAD) biofilm

Water Science & Technology ◽

10.2166/wst.2017.035 ◽

2017 ◽

Vol 75 (7) ◽

pp. 1712-1721 ◽

Cited By ~ 14

Author(s):

Zhaoming Zheng ◽

Yun Li ◽

Jun Li ◽

Yanzhuo Zhang ◽

Wei Bian ◽

...

Keyword(s):

Carbon Source ◽

Nitrogen Removal ◽

Municipal Wastewater ◽

Inorganic Nitrogen ◽

Carbon Sources ◽

Biofilm Reactor ◽

Partial Nitrification ◽

Anammox Bacteria ◽

Coupling Process ◽

Anammox Activity

The aim of the present work was to evaluate the effects of carbon sources and chemical oxygen demand (COD)/NO2−-N ratios on the anammox–denitrification coupling process of the simultaneous partial nitrification, anammox and denitrification (SNAD) biofilm. Also, the anammox activities of the SNAD biofilm were investigated under different temperature. Kaldnes rings taken from the SNAD biofilm reactor were operated in batch tests to determine the nitrogen removal rates. As a result, with the carbon source of sodium acetate, the appropriate COD/NO2−-N ratios for the anammox–denitrification coupling process were 1 and 2. With the COD/NO2−-N ratios of 1, 2, 3, 4 and 5, the corresponding NO2−-N consumption via anammox was 87.1%, 52.2%, 29.3%, 23.7% and 16.3%, respectively. However, with the carbon source of sodium propionate and glucose, the anammox bacteria was found to perform higher nitrite competitive ability than denitrifiers at the COD/NO2−-N ratio of 5. Also, the SNAD biofilm could perform anammox activity at 15 °C with the nitrogen removal rate of 0.071 kg total inorganic nitrogen per kg volatile suspended solids per day. These results indicated that the SNAD biofilm process might be feasible for the treatment of municipal wastewater at normal temperature.

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A continuous plug-flow anaerobic/aerobic/anoxic/aerobic (AOAO) process treating low COD/TIN domestic sewage: Realization of partial nitrification and extremely advanced nitrogen removal

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.145387 ◽

2021 ◽

Vol 771 ◽

pp. 145387

Author(s):

Yan Feng ◽

Yongzhen Peng ◽

Bo Wang ◽

Bo Liu ◽

Xiyao Li

Keyword(s):

Nitrogen Removal ◽

Plug Flow ◽

Domestic Sewage ◽

Partial Nitrification ◽

Advanced Nitrogen Removal

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The nitrogen removal potential of predenitrification systems in sensitive coastal areas

Water Science & Technology ◽

10.2166/wst.1995.0218 ◽

1995 ◽

Vol 32 (7) ◽

pp. 135-142

Author(s):

E. Görgün ◽

N. Artan ◽

D. Orhon ◽

R. Tasli

Keyword(s):

Water Quality ◽

Wastewater Treatment ◽

Nitrogen Removal ◽

Retention Time ◽

Treatment Process ◽

Hydraulic Retention Time ◽

Domestic Sewage ◽

Coastal Areas ◽

Careful Evaluation ◽

Denitrification Kinetics

Effective nitrogen removal is now required to protect water quality in sensitive coastal areas. This involves a much more difficult treatment process than for conventional domestic sewage as wastewater quantity and quality exhibits severe fluctuations in touristic zones. Activated sludge is currently the most widely used wastewater treatment and may be upgraded as a predenitrification system for nitrogen removal. Interpretation of nitrification and denitrification kinetics reveal a number of useful correlations between significant parameters such as sludge age, C/N ratio, hydraulic retention time, total influent COD. Nitrogen removal potential of predenitrification may be optimized by careful evaluation of wastewater character and the kinetic correlations.

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Effect of draft tube diameter on nitrogen removal from domestic sewage in a draft tube type reactor

Water Science & Technology ◽

10.2166/wst.1998.0076 ◽

1998 ◽

Vol 38 (1) ◽

pp. 319-326

Author(s):

Taku Fujiwara ◽

Iso Somiya ◽

Hiroshi Tsuno ◽

Yoshio Okuno

Keyword(s):

Flow Rate ◽

Nitrogen Removal ◽

Draft Tube ◽

Domestic Sewage ◽

Tube Diameter ◽

Continuous Treatment ◽

Anoxic Zone ◽

Type Reactor ◽

Tube Type ◽

Volumetric Loading

The effect of the ratio of draft tube diameter to reactor diameter (Di/Do) on the efficiency of nitrogen removal from domestic sewage is discussed based on liquid-circulating flow rate and continuous treatment data. More than 2.5 minutes of circulation time in the annulus part, which is required to create an anoxic zone, could be maintained under operating conditions in which air flow rate per reactor volume was 2 m3/(m3 · hr) and Di/Do was 0.19. When Di/Do was set at 0.19, the average total organic carbon (TOC), total nitrogen (TN) and dissolved nitrogen (DN) removal efficiencies were 83.2%, 72.1% and 71.6%, respectively, which were higher than those when Di/Do was at 0.26 or 0.36. From these results, it is concluded that 0.19 is the best Di/Do for nitrogen removal in a draft-tube type reactor with an effective depth of 4.0m under the treatment condition in which the BOD volumetric loading rate is in the range 0.22 to 0.46 kgBOD/(m3 · day). More than 80% nitrification and denitrification efficiencies can be achieved simultaneously when both conditions, the aerobic zone ratio being more than 0.2, and the anoxic zone ratio being more than 0.3, are satisfied.

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Light as a Novel Inhibitor of Nitrite-Oxidizing Bacteria (NOB) for the Mainstream Partial Nitrification of Wastewater Treatment

Processes ◽

10.3390/pr9020346 ◽

2021 ◽

Vol 9 (2) ◽

pp. 346

Author(s):

Keugtae Kim ◽

Yong-Gyun Park

Keyword(s):

Wastewater Treatment ◽

Blue Light ◽

Nitrogen Removal ◽

Municipal Wastewater ◽

Partial Nitrification ◽

Biological Nutrient Removal ◽

Nitrite Accumulation ◽

Light Illumination ◽

Ammonia Oxidizing Bacteria ◽

Nitrite Oxidizing Bacteria

Conventional biological nutrient removal processes in municipal wastewater treatment plants are energy-consuming, with oxygen supply accounting for 45–75% of the energy expenditure. Many recent studies examined the implications of the anammox process in sidestream wastewater treatment to reduce energy consumption, however, the process did not successfully remove nitrogen in mainstream wastewater treatment with relatively low ammonia concentrations. In this study, blue light was applied as an inhibitor of nitrite-oxidizing bacteria (NOB) in a photo sequencing batch reactor (PSBR) containing raw wastewater. This simulated a biological nitrogen removal system for the investigation of its application potential in nitrite accumulation and nitrogen removal. It was found that blue light illumination effectively inhibited NOB rather than ammonia-oxidizing bacteria due to their different sensitivity to light, resulting in partial nitrification. It was also observed that the NOB inhibition rates were affected by other operational parameters like mixed liquor suspended solids (MLSS) concentration and sludge retention time (SRT). According to the obtained results, it was concluded that the process efficiency of partial nitrification and anammox (PN/A) could be significantly enhanced by blue light illumination with appropriate MLSS concentration and SRT conditions.

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