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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Aeration control for simultaneous nitrification-denitrification in a biological aerated filter using internal model
C Lemoine1, M Payraudeau, J Meinhold
1Anjou Recherche, chemin de la digue, BP 76, 78603 Maisons-Laffitte, France. cyrille.lemoine@grouve.com
Summary
A novel feedback/feedforward control strategy enhances simultaneous nitrification and denitrification in biological aerated filters. This optimized aeration control improves nitrogen removal by 5% and reduces air usage by 15-20%.
Area of Science:
- Environmental Engineering
- Water Treatment Technologies
- Biotechnology
Background:
- Biological aerated filters (BAFs) can achieve simultaneous nitrification and denitrification (S/DN).
- S/DN systems are highly sensitive to aeration control strategies, with poor control leading to reduced efficiency.
- Existing control methods often fail to maintain optimal performance in dynamic conditions.
Purpose of the Study:
- To develop and evaluate a new, robust aeration control strategy for simultaneous nitrification/denitrification in BAFs.
- To improve the nitrogen removal efficiency and reduce operational costs associated with BAF systems.
Main Methods:
- A novel feedback/feedforward (FF/FB) control strategy was developed, utilizing ammonia measurements and inlet/outlet data.
- The strategy dynamically estimates required airflow velocity based on calculated nitrogen load, with a feedback loop for setpoint correction.
- The FF/FB control was implemented and tested over 18 months on a pilot-scale BAF plant with two coupled cells.
Main Results:
- The developed FF/FB control strategy demonstrated superior performance compared to classical controllers.
- Nitrogen removal performance increased by 5% under the new control strategy.
- Airflow requirements were reduced by 15-20%, indicating significant operational cost savings and a rapid return on investment.
Conclusions:
- The proposed FF/FB control strategy effectively optimizes aeration for simultaneous nitrification and denitrification in BAFs.
- This advanced control approach significantly enhances treatment efficiency and reduces energy consumption.
- The findings suggest a practical and cost-effective solution for improving nitrogen removal in industrial wastewater treatment.
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