Performance and kinetic modeling of an aerated submerged fixed-film bioreactor for BOD and nitrogen removal from municipal wastewater

This research was carried out using lab-scaled Integrated Fixed Film Activated Sludge (IFAS) process with fabious media and anoxic process in order to reduce the concentration of ammonia nitrogen and nitrate nitrogen in municipal wastewater from Yangon City, Myanmar. The required wastewater sample was collected from the wastewater treatment plant of Yangon City Development Committee (YCDC). Ten experiments were conducted with five operational conditions and they lasted about four months from February to May 2018. The rate of air supply for the aeration tank through these experiments was about 8 m3 /day. This paper describes the evaluation on nitrogen removal efficiency of the lab-scaled treatment system depending on the results from the experiments. Due to the different operational conditions through these experiments, the F/M ratio of IFAS process varied between 0.1 and 0.9 d -1 and SRT of IFAS process ranged between 6.0 days and 8.3 days. Moreover, the F/M ratio fluctuated between 0.2 d -1 and 0.7 d -1 as well as the Specific Rate of Denitrification (SRDN) altered between 0.23 g NO3-N/g MLSS and 0.33 g NO3-N/g MLSS in the anoxic process. According to the outcomes of the experiments, the maximum removal efficiency for ammonia nitrogen and nitrate nitrogen were about 98.2% and 97.7%, respectively. However, the optimum treatment efficiency for both NH3-N and NO3-N concentration was obtained at the ninth experiment with about 0.1 d-1 of the F/M ratio and about 6.4 days of SRT in aerobic reactor while the F/M ratio, SRDN and anoxic residence time of anoxic process were about 0.26 d-1 , 0.27 g NO3-N/ g MLSS and 48 hours, respectively. About 500 mg/l of ammonia nitrogen can be reduced to about 30 mg/l and about 2600 mg/l of nitrate nitrogen can be reduced to about 61 mg/l, respectively in this ninth experiment. The optimum treatment efficiency for ammonia nitrogen and nitrate nitrogen were about 94.0 % and 98.0 %, respectively.

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Effect of Carrier Filling Ratios on Dissolved Organic Nitrogen Removal in Integrated Fixed-Film Activated Sludge Systems Treating Municipal Wastewater

ACS ES&T Engineering ◽

10.1021/acsestengg.0c00236 ◽

2021 ◽

Author(s):

Haidong Hu ◽

Boyang Zhu ◽

Liqin Han ◽

Hongqiang Ren

Keyword(s):

Activated Sludge ◽

Nitrogen Removal ◽

Dissolved Organic Nitrogen ◽

Organic Nitrogen ◽

Municipal Wastewater ◽

Fixed Film ◽

Activated Sludge Systems

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ENHANCED NITROGEN REMOVAL FROM REJECT WATER OF MUNICIPAL WASTEWATER TREATMENT PLANTS USING A NOVEL EXCESS ACTIVATED SLUDGE (EAS) BASED NITRIFICATION AND DENITRIFICATION PROCESS

Environmental Engineering and Management Journal ◽

10.30638/eemj.2013.168 ◽

2013 ◽

Vol 12 (7) ◽

pp. 1367-1373

Author(s):

Yongzhe Yang ◽

Xiaoxia Yang ◽

Wei Li ◽

Xinchao Guo

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Nitrogen Removal ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Municipal Wastewater Treatment ◽

Reject Water ◽

Nitrification And Denitrification ◽

Municipal Wastewater Treatment Plants ◽

Denitrification Process

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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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Cultivation of rice for animal feed with circulated irrigation of treated municipal wastewater for enhanced nitrogen removal: comparison of cultivation systems feeding irrigation water upward and downward

Water Science & Technology ◽

10.2166/wst.2015.251 ◽

2015 ◽

Vol 72 (4) ◽

pp. 579-584 ◽

Cited By ~ 7

Author(s):

A. Muramatsu ◽

H. Ito ◽

A. Sasaki ◽

A. Kajihara ◽

T. Watanabe

Keyword(s):

Nitrogen Removal ◽

Irrigation Water ◽

Rice Plant ◽

Municipal Wastewater ◽

Animal Feed ◽

Paddy Fields ◽

Treated Wastewater ◽

Human Consumption ◽

Cultivation System ◽

Treated Municipal Wastewater

To achieve enhanced nitrogen removal, we modified a cultivation system with circulated irrigation of treated municipal wastewater by using rice for animal feed instead of human consumption. The performance of this modified system was evaluated through a bench-scale experiment by comparing the direction of circulated irrigation (i.e. passing through paddy soil upward and downward). The modified system achieved more than three times higher nitrogen removal (3.2 g) than the system in which rice for human consumption was cultivated. The removal efficiency was higher than 99.5%, regardless of the direction of circulated irrigation. Nitrogen in the treated municipal wastewater was adsorbed by the rice plant in this cultivation system as effectively as chemical fertilizer used in normal paddy fields. Circulated irrigation increased the nitrogen released to the atmosphere, probably due to enhanced denitrification. Neither the circulation of irrigation water nor its direction affected the growth of the rice plant and the yield and quality of harvested rice. The yield of rice harvested in this system did not reach the target value in normal paddy fields. To increase this yield, a larger amount of treated wastewater should be applied to the system, considering the significant amount of nitrogen released to the atmosphere.

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