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Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors
Published on: December 6, 2018
Shortcut nitrification-denitrification by real-time control strategies
Dawen Gao1, Yongzhen Peng, Baikun Li
1State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang, China. gaodw@hit.edu.cn
Bioresource Technology
|December 24, 2008
Summary
Real-time control stabilizes shortcut nitrification-denitrification by preventing excess aeration. This strategy maintains high nitrosation ratios, crucial for efficient wastewater treatment.
Area of Science:
- Environmental Science
- Water Treatment Engineering
Background:
- Shortcut nitrification-denitrification is vital for nitrogen removal in wastewater.
- Instability issues, particularly from excess aeration, hinder process efficiency.
Purpose of the Study:
- To address the instability of shortcut nitrification-denitrification.
- To implement and evaluate real-time control strategies for process stabilization.
Main Methods:
- Investigated the impact of excess aeration on nitrification modes.
- Utilized real-time monitoring of Oxidation-Reduction Potential (ORP) and pH curves.
- Developed a control strategy to stop aeration upon completion of nitrosation.
Main Results:
- Excess aeration shifted nitrification from shortcut to full nitrification, reducing the nitrosation ratio from 96% to 29%.
- Real-time control accurately detected nitrification modes via ORP and pH.
- Stopping aeration post-nitrosation maintained a nitrosation ratio above 96%.
Conclusions:
- Real-time control effectively prevents excess aeration.
- The proposed strategy ensures stable and efficient shortcut nitrification-denitrification.
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