Numerical Modeling of Type I Circular Sedimentation Tank
Publication: Journal of Environmental Engineering
Volume 137, Issue 3
Abstract
A numerical model for Type I circular sedimentation tanks (center feed) has been developed to provide useful information for circular tank operation. The unsteady flow process in circular sedimentation tanks is divided by numerous time intervals in which flow and sediment transport are considered to be steady. The other feature for this model is that particle size distribution of raw water is nonuniform. A numerical experiment based on the proposed model is carried out, and the results were compared with results from other models. The comparison shows that this model can provide more information, such as variations of water elevation, overall removal efficiency, bottom sludge thickness, and particle size distribution at outlet. In addition, this model had the advantage of optimizing the tank dimensions based on the sludge raking frequency and preferred removal efficiency. After simplification of the model, this model is practical in determining the overall removal efficiency and dimension of the tank based on different inflow situations for tank design.
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Acknowledgments
This research was supported in part by the Natural Science and Engineering Research Council of Canada.NSERC
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Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 137 • Issue 3 • March 2011
Pages: 196 - 204
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Feb 4, 2009
Accepted: Aug 1, 2010
Published online: Aug 5, 2010
Published in print: Mar 1, 2011
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