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Published on: September 26, 2016
Real-time control strategy for simultaneous nitrogen and phosphorus removal using aerobic granular sludge
N Kishida1, S Tsuneda, Y Sakakibara
1Department of Civil and Environmental Engineering, Waseda University, 3-4-1 Ohkubo, Tokyo 169-8555, Japan. nkishida@kurenai.waseda.jp
Summary
A new real-time control strategy using electric conductivity and pH derivatives enables stable, simultaneous removal of nitrogen and phosphorus with aerobic granular sludge. This system automatically adjusts treatment cycles for optimal wastewater management.
Area of Science:
- Environmental Engineering
- Wastewater Treatment Technologies
- Microbial Ecology
Background:
- Simultaneous nitrogen and phosphorus removal is crucial for wastewater treatment.
- Aerobic granular sludge (AGS) offers potential for efficient nutrient removal.
- Controlling AGS processes for stable nutrient removal remains challenging.
Purpose of the Study:
- To develop and evaluate a real-time control strategy for stable, simultaneous nitrogen and phosphorus removal using AGS.
- To optimize treatment cycle lengths based on monitored parameters.
- To assess the system's performance under fluctuating influent conditions.
Main Methods:
- Implementation of a real-time control system in a sequencing batch reactor (SBR).
- Monitoring of time derivatives of electric conductivity (EC) and pH to determine key process stages.
- Automatic adjustment of anaerobic, oxic, and anoxic phase durations.
Main Results:
- Stable and simultaneous removal of nitrogen and phosphorus was achieved, with effluent concentrations below 0.3 mg/L for NH4-N, NOx-N, and PO4-P.
- The control system effectively managed biomass fluctuations during the startup period.
- Consistent performance was maintained even with significant variations in influent wastewater characteristics.
Conclusions:
- The developed real-time control strategy is highly effective for achieving stable simultaneous nitrogen and phosphorus removal with AGS.
- Dynamic adjustment of treatment phases is superior to fixed phase lengths for consistent nutrient removal.
- This approach offers a robust solution for advanced wastewater treatment.
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