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Updated: Jun 19, 2026
08:05
Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
[Biological nitrogen removal with excess nitrogen uptake by microorganisms]
Jiu-hua Deng1, Dong-bo Wang, Xiao-ming Li
1College of Environmental Science and Engineering, Hunan University, Changsha 410082, China. dengjh@hnu.cn
Huan Jing Ke Xue= Huanjing Kexue
|October 6, 2009
Summary
Sequencing batch reactors achieved high nitrogen removal rates. Optimal pH conditions were explored, revealing that nitrogen removal occurred via sludge discharge rather than traditional nitrification/denitrification.
Area of Science:
- Environmental Engineering
- Water Treatment Technologies
- Wastewater Management
Context:
- Investigated nitrogen removal efficiency in sequencing batch reactors (SBRs) using simulated municipal wastewater.
- Evaluated the impact of different pH levels (7.0 and 8.0) on SBR performance.
- Analyzed the removal of total inorganic nitrogen (TIN) under specific operational conditions.
Purpose:
- To determine the optimal pH for nitrogen removal in SBRs.
- To understand the mechanism of nitrogen removal in the studied SBR system.
- To compare nitrogen removal rates at different pH values.
Summary:
- SBRs demonstrated effective nitrogen removal, with higher rates observed at pH 7.0 (above 85%) compared to pH 8.0 (around 70%).
- Observed effluent ammonium and nitrate/nitrite levels were significantly lower at pH 8.0 (0-1 mg/L and 8-10 mg/L) than at pH 7.0 (0-5 mg/L and 1-2 mg/L).
- Nitrogen removal was primarily attributed to the discharge of nitrogen-rich sludge, not conventional nitrification/denitrification.
Impact:
- Highlights an alternative mechanism for nitrogen removal in SBRs, focusing on sludge management.
- Provides insights into optimizing SBR operation for enhanced nitrogen removal in wastewater treatment.
- Suggests potential for sludge valorization as a nitrogen sink in wastewater treatment processes.
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