One-Dimensional Clarifier Model with Sludge Blanket Heights
Publication: Journal of Environmental Engineering
Volume 122, Issue 12
Abstract
A one-dimensional clarifier model employing a concentration and feed velocity dependent dispersion coefficient was coupled with an algorithm for predicting sludge blanket height. The model was successfully calibrated using blanket heights; effluent suspended solids and return activated sludge concentrations; and the Vesilind parameters V0 and b . These data were collected from one of the secondary clarifiers at a full-scale activated sludge plant. Model validity was confirmed by comparing predictions of the calibrated model against separate sets of data collected from the same clarifier. The model outperformed other well-known models in predicting clarifier overloading. Better performance of the present model can be attributed to its ability to portray, through a dependence of dispersion coefficient on feed velocity, the detrimental effect of increasing hydraulic loading (for any given applied solids flux) on clarifier performance.
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Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 122 • Issue 12 • December 1996
Pages: 1094 - 1100
Copyright
Copyright © 1996 American Society of Civil Engineers.
History
Published online: Dec 1, 1996
Published in print: Dec 1996
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