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Kinetic model for biological nitrogen removal using shortcut nitrification-denitrification process in sequencing
Dawen Gao1, Yongzhen Peng, Wei-Min Wu
1State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, P.R. China. gaodw@hit.edu.cn
Environmental Science & Technology
|June 15, 2010
Summary
A kinetic model for shortcut nitrification-denitrification was developed and validated using a sequencing batch reactor (SBR) treating soybean curd wastewater. The model accurately predicts nitrogen removal efficiency under varying conditions, aiding wastewater treatment optimization.
Area of Science:
- Environmental Engineering
- Water Treatment Technologies
- Biochemical Engineering
Background:
- Shortcut nitrification-denitrification is an efficient nitrogen removal process.
- Sequencing batch reactors (SBRs) are versatile for wastewater treatment.
- Wastewater from soybean curd processing presents unique treatment challenges.
Purpose of the Study:
- To develop and validate a kinetic model for the shortcut nitrification-denitrification process in an SBR.
- To estimate kinetic parameters for nitrification and denitrification steps.
- To assess the model's predictive capability for nitrogen removal.
Main Methods:
- Development of a kinetic model for shortcut nitrification-denitrification.
- Laboratory-scale SBR experiments using soybean curd processing wastewater.
- Estimation of kinetic parameters (maximum specific rates, half-maximum rate concentrations) at different dissolved oxygen (DO) levels.
- Validation of model predictions against experimental data.
Main Results:
- The kinetic model accurately predicted nitrification rates (R = 0.9902) under varying ammonium concentrations and DO levels (0.5 and 3.5 mg L(-1)).
- Nitrite removal during denitrification approached zero-order kinetics when COD concentration exceeded 100 mg L(-1).
- Denitrification rate showed limited sensitivity to nitrite and organic matter concentrations within tested ranges.
Conclusions:
- The developed kinetic model effectively simulates shortcut nitrification-denitrification in SBRs.
- The model can predict nitrogen removal performance based on influent characteristics (NH(4)(+)-N, COD) and operational parameters (DO).
- This kinetic model provides a valuable tool for optimizing SBR operation for enhanced nitrogen removal from industrial wastewater.
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