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Towards more predictive clarification models via experimental determination of flocculent settling coefficient value
Khoa Nam Ngo1, Tim Van Winckel2, Arash Massoudieh3
1District of Columbia Water and Sewer Authority, Blue Plains Advanced Wastewater Treatment Plant, Washington DC, USA; Department of Civil and Environmental Engineering, The Catholic University of America, USA.
Water Research
|December 28, 2020
Summary
This study introduces a practical method to calculate the flocculent settling coefficient (rp) using sludge characteristics. This improves wastewater clarifier models for better effluent quality prediction.
Area of Science:
- Environmental Engineering
- Water Treatment Technologies
- Wastewater Treatment
Background:
- Improved settleability is crucial for new wastewater treatment innovations.
- Current clarifier models often lack experimental validation for parameters like the flocculent settling coefficient (rp).
- Existing models use rp as a calibration parameter rather than a sludge characteristic.
Purpose of the Study:
- To develop a practical, experimental method for calculating the flocculent settling coefficient (rp) from sludge characteristics.
- To enhance the predictive capabilities of one-dimensional (1D) wastewater clarifier models.
- To establish a link between sludge properties and clarifier performance.
Main Methods:
- Developed an empirical function to calculate rp based on sludge characteristics.
- Utilized the threshold of flocculation (TOF) as a key experimental parameter, correlating it with particle collision efficiency.
- Validated the empirical function using four years of data from five different activated sludge systems.
Main Results:
- The proposed empirical function accurately calculates rp from sludge characteristics.
- The threshold of flocculation (TOF) showed a direct correlation with effluent quality across various systems.
- The method allows for improved prediction of effluent quality using 1D clarifier models.
Conclusions:
- The developed empirical function enhances the predictive power of wastewater clarifier models.
- Linking sludge characteristics to rp through TOF provides a more robust modeling approach.
- This research advances the development of more accurate and predictive clarification models for wastewater treatment.
Keywords:
Discrete settlingFlocculationSecondary clarifierStokesian settlingTakács modelVesilind parametersMore Related Videos
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