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Long-term dynamic and pseudo-state modeling of complete partial nitrification process at high nitrogen loading rates
Moomen Soliman1, Ahmed Eldyasti1
1Department of Civil Engineering, Lassonde School of Engineering, York University, Toronto, Ontario M3J 1P3, Canada.
Bioresource Technology
|March 13, 2017
Summary
This study calibrated a process model for partial nitrification in wastewater treatment. The model accurately predicts effluent quality, improving the feasibility of the nitrite shunt process for high-nitrogen wastewater.
Area of Science:
- Environmental Engineering
- Wastewater Treatment Technologies
- Biochemical Engineering
Background:
- Partial nitrification is crucial for the nitrite shunt and Anammox processes in wastewater treatment.
- Maintaining stable nitrite accumulation at high nitrogen loading rates (NLR) remains a significant challenge, impacting process feasibility for high-nitrogen wastewater.
- Existing methods for modeling such processes often require complex respirometric analysis.
Purpose of the Study:
- To calibrate and validate a BioWin® process model for a lab-scale sequencing batch reactor (SBR) performing partial nitrification.
- To describe the long-term dynamic behavior of the SBR under varying operational conditions.
- To introduce an identifiability analysis to simplify SBR model calibration, removing the need for respirometric analysis.
Main Methods:
- Utilized operational data from a lab-scale SBR operating at nitrogen loading rates (NLRs) from 0.3-1.2 kg/(m³d).
- Employed a process model developed in BioWin® for calibration and validation.
- Integrated an identifiability analysis into the calibration protocol.
Main Results:
- The calibrated model accurately predicted daily effluent concentrations of ammonia, nitrate, and nitrite.
- The model also accurately predicted effluent alkalinity and pH across different operational conditions.
- The identifiability analysis successfully eliminated the requirement for respirometric analysis during calibration.
Conclusions:
- The validated BioWin® model provides an accurate representation of partial nitrification in an SBR.
- The model enhances the understanding and prediction of process performance, supporting the feasibility of the nitrite shunt process.
- The integrated identifiability analysis offers a more efficient approach to SBR model calibration for wastewater treatment applications.
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