[Comparison study on phosphorus removal between single-stage oxic process and anaerobic/aerobic process]
Fan Yang1, Dong-Bo Wang, Xiao-Ming Li
1College of Environmental Science and Engineering, Hunan University, Changsha 410082, China. yfqihang@163.com
Huan Jing Ke Xue= Huanjing Kexue
|February 3, 2012
Summary
The anaerobic/aerobic Sequencing Batch Reactor (SBR1) process removed 91.72% of phosphorus, outperforming the single-stage oxic SBR2 (71.70%). This highlights SBR1
Area of Science:
- Environmental Science
- Microbiology
- Wastewater Treatment
Background:
- Municipal wastewater contains extensive acetate, a key carbon source.
- Phosphorus removal is critical for preventing eutrophication.
- Sequencing Batch Reactors (SBRs) are widely used in wastewater treatment.
Purpose of the Study:
- To compare phosphorus removal efficiency between an anaerobic/aerobic SBR (SBR1) and a single-stage oxic SBR (SBR2).
- To investigate the role of polyhydroxyalkanoates (PHA) and glycogen in phosphorus removal under different SBR configurations.
- To analyze phosphorus release dynamics during idle periods in both SBR systems.
Main Methods:
- Two SBRs (SBR1: anaerobic/aerobic; SBR2: single-stage oxic) were operated for three months.
- Acetate was used as the sole carbon source in both systems.
- Phosphorus removal efficiency, total phosphorus (TP) removed per unit Mixed Liquor Suspended Solids (MLSS), PHA, and glycogen content were measured.
Main Results:
- SBR1 achieved 91.72% phosphorus removal efficiency and 3.23 mg/g MLSS TP removal, significantly higher than SBR2 (71.70% and 2.91 mg/g MLSS, respectively).
- SBR1 showed increased PHA with decreased glycogen, while SBR2 exhibited PHA synthesis coupled with glycogen accumulation, suggesting glycogen is not essential for PHA synthesis in oxic processes.
- SBR2 released significantly more phosphorus (13.28 mg/L) than SBR1 (2.6 mg/L) during idle periods.
Conclusions:
- The anaerobic/aerobic SBR process demonstrates superior phosphorus removal efficiency compared to the single-stage oxic SBR process.
- Microbial energy storage and consumption patterns differ between the two SBR configurations, influencing phosphorus removal performance.
- Understanding these metabolic differences is crucial for optimizing SBR design for enhanced phosphorus removal.
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