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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Enhanced biological nutrient removal in sequencing batch reactors operated as static/oxic/anoxic (SOA) process
Dechao Xu1, Hongbo Chen, Xiaoming Li
1College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.
Bioresource Technology
|June 26, 2013
Summary
The novel static/oxic/anoxic (SOA) process effectively removes nutrients. Adjusting the anoxic phase prevents secondary phosphorus release, optimizing biological nutrient removal (BNR) in wastewater treatment.
Area of Science:
- Environmental Science
- Environmental Engineering
- Microbiology
Background:
- Conventional anaerobic stages in biological nutrient removal (BNR) processes can be replaced.
- Wastewater treatment requires efficient removal of ammonia and phosphorus.
- Simultaneous nitrification and denitrification are desirable for nutrient removal.
Purpose of the Study:
- To evaluate an innovative static/oxic/anoxic (SOA) activated sludge process for enhanced biological nutrient removal (BNR).
- To investigate the efficacy of the static phase as a substitute for the conventional anaerobic stage.
- To assess nutrient removal performance at different influent ammonia concentrations (20 and 40 mg/L).
Main Methods:
- Implementation of a static/oxic/anoxic (SOA) activated sludge process in two reactors (R1 and R2).
- Operation with varying influent ammonia concentrations (20 mg/L in R1, 40 mg/L in R2).
- Monitoring of nutrient concentrations, polyphosphate accumulating organisms (PAOs) activity, and denitrification rates.
Main Results:
- The static phase effectively replaced the conventional anaerobic stage, supporting biological nutrient removal (BNR).
- Secondary phosphorus release occurred in R1 due to NOx(-) depletion, while R2 achieved denitrifying phosphorus removal with sufficient NOx(-).
- Simultaneous nitrification-denitrification was observed in both reactors, with glycogen supporting post-denitrification.
Conclusions:
- The static/oxic/anoxic (SOA) process demonstrates potential for enhanced biological nutrient removal (BNR).
- Optimizing anoxic stirring duration is crucial to prevent secondary phosphorus release, particularly at lower ammonia concentrations.
- The SOA process offers a viable alternative for efficient nutrient management in wastewater treatment.
Keywords:
Biological nutrient removal (BNR)GlycogenPost-anoxicSimultaneous nitrification–denitrificationStatic phaseMore Related Videos
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