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Updated: Jul 16, 2026
08:13
A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Development of sequencing batch reactor with step feed and recycle
1Department of Civil and Environmental Engineering, Chonnam National University, Gwangju 500-757, Korea.
Summary
This study developed an optimized Sequencing Batch Reactor (SBR) process to improve nitrogen and phosphorus removal in combined sewers with low biochemical oxygen demand (BOD). The enhanced SBR achieved high removal rates, addressing a key challenge in wastewater treatment.
Area of Science:
- Environmental Science
- Water Treatment Engineering
- Wastewater Management
Background:
- Sequencing Batch Reactor (SBR) processes demonstrate high nitrogen and phosphorus removal in areas with separated sewers.
- However, SBR efficiency decreases significantly in combined sewer systems due to lower organic (biochemical oxygen demand - BOD) concentrations, which are crucial for denitrification.
- Korean sewer systems are predominantly combined, exhibiting BOD levels insufficient for effective denitrification.
Purpose of the Study:
- To develop an optimized SBR process capable of enhancing organic matter utilization.
- To improve the removal efficiency of nitrogen (N) and phosphorus (P) in low-BOD wastewater.
- To address the limitations of conventional SBRs in combined sewer systems.
Main Methods:
- Implementation of a step-feed strategy within the SBR process.
- Integration of a recycle stream to optimize carbon source availability.
- Application of the modified SBR to treat wastewater with low influent BOD.
Main Results:
- Achieved a biochemical oxygen demand (BOD) removal rate of 95.4%.
- Demonstrated a total nitrogen (T-N) removal efficiency of 81.4%.
- Reported a total phosphorus (T-P) removal rate of 86.1% despite low influent BOD.
Conclusions:
- The developed step-feed and recycle SBR process effectively overcomes the challenge of low organic concentration in combined sewers.
- This optimized SBR approach significantly enhances nitrogen and phosphorus removal efficiencies.
- The findings offer a viable solution for improving wastewater treatment in regions with combined sewer systems and low BOD levels.
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