Complete nitrogen removal from municipal wastewater via partial nitrification by appropriately alternating anoxic/aerobic conditions in a continuous plug-flow step feed process

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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Applicability of two-stage anoxic/oxic shortcut nitrogen removal via partial nitrification and partial denitrification for municipal wastewater by adding sludge fermentation products continuously

Chemosphere ◽

10.1016/j.chemosphere.2021.132053 ◽

2021 ◽

pp. 132053

Author(s):

Yao Chen ◽

Ying Zhang ◽

Liang Zhang ◽

Shujun Zhang ◽

Yongzhen Peng

Keyword(s):

Nitrogen Removal ◽

Municipal Wastewater ◽

Partial Nitrification ◽

Two Stage ◽

Fermentation Products ◽

Shortcut Nitrogen Removal

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Enhanced nitrogen removal from low COD/TIN mainstream wastewater in a continuous plug-flow reactor via partial nitrification, simultaneous anammox and endogenous denitrification (PN-SAED) process

Bioresource Technology ◽

10.1016/j.biortech.2021.126539 ◽

2021 ◽

pp. 126539

Author(s):

Yan Feng ◽

Bo Wang ◽

Yongzhen Peng ◽

Xiyao Li ◽

Qiong Zhang

Keyword(s):

Nitrogen Removal ◽

Flow Reactor ◽

Plug Flow ◽

Plug Flow Reactor ◽

Partial Nitrification

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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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