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Comparison and Optimization of Intermittent Aeration/Interval Aeration for Enhancing Nitrogen Removal in Continuous
Ruochen Hu1, Zeming An1, Yuanqi Gu1
1National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
Bioresource Technology
|March 24, 2026
Summary
Interval aeration in anaerobic/oxic/anoxic (AOA) systems optimizes carbon source utilization for superior nitrogen removal. This method enhances efficiency by minimizing dissolved oxygen and preserving internal carbon stores.
Area of Science:
- Environmental Science
- Wastewater Treatment Engineering
- Microbial Ecology
Background:
- Advanced nitrogen removal relies on anaerobic/oxic/anoxic (AOA) processes.
- Effective carbon source utilization is crucial for AOA efficiency but challenged by aerobic zone losses.
Purpose of the Study:
- To compare the effectiveness of continuous, intermittent, and interval aeration in the aerobic zone of AOA systems.
- To optimize carbon source utilization and enhance total inorganic nitrogen (TIN) removal from domestic wastewater.
Main Methods:
- A comparative study using real domestic wastewater under three distinct aerobic zone aeration modes: continuous, intermittent, and interval.
- Evaluation of the anaerobic/oxic/anoxic functional volume ratio and aeration/rest cycles.
- Measurement of total inorganic nitrogen (TIN) removal efficiency and assessment of carbon source utilization and dissolved oxygen levels.
Main Results:
- Continuous aeration led to significant loss of both internal and external carbon sources.
- Intermittent aeration improved external carbon utilization, achieving 77.6% TIN removal with a 1:4:3 volume ratio and 20 min:20 min aeration/rest.
- Interval aeration minimized dissolved oxygen carryover, preserved internal carbon, and achieved the highest TIN removal efficiency of 77.9%.
Conclusions:
- Interval aeration offers significant operational and metabolic advantages over continuous and intermittent aeration for AOA systems.
- Optimizing aeration strategies, particularly interval aeration, is key to enhancing nitrogen removal and resource utilization in wastewater treatment.
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