A phenomenological retention tank model using settling velocity distributions.
T Maruejouls1, P A Vanrolleghem, G Pelletier
1Département de génie civil et de génie des eaux, Université Laval, 1065 av. de la Médecine, Québec, Qc, G1V 0A6, Canada.
Water Research
|December 27, 2011
Summary
This study models how particle settling velocity changes in retention tanks for combined sewage. The enhanced model accounts for settling and resuspension, improving pollutant behavior characterization in wastewater treatment.
Area of Science:
- Environmental Engineering
- Wastewater Treatment
- Fluid Dynamics
Background:
- Sedimentation in retention tanks is influenced by particle settling velocity.
- Pollutant behavior, particularly settling velocity distribution, is not well understood in these systems.
Purpose of the Study:
- To model the change in particle settling velocity distribution in combined sewage within off-line retention tanks.
- To enhance existing models by incorporating settling velocity and resuspension dynamics.
Main Methods:
- Implemented a previously published phenomenological model (Lessard and Beck, 1991) in wastewater management software.
- Validated the model with full-scale field data.
- Integrated particle settling velocity distribution and resuspension due to pumping.
Main Results:
- The study successfully adapted and tested a model for retention tank sedimentation.
- The improved model better characterizes particle behavior by including settling and resuspension.
- Model performance was demonstrated through comparison with field data from a rain event.
Conclusions:
- The developed phenomenological model provides a better understanding of particle settling velocity distribution changes in retention tanks.
- The model's enhancements offer improved characterization of pollutant behavior during wastewater treatment.
- This work contributes to more accurate wastewater management modeling.
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