Enhanced Filter Performance by Fluidized-Bed Pretreatment with : Observations and Model Simulation
Publication: Journal of Environmental Engineering
Volume 138, Issue 4
Abstract
Fluidized-bed pretreatment of a rapid sand filter with alum [] has been shown to significantly improve performance during the initial portion of filter operation. Two alternative mechanisms are hypothesized by which alum pretreatment acts to improve particle removal: (1) coats the sand filter medium, and alters its porosity. (2) Precipitated embedded within the media pores acts as an additional filter medium that increases the particle capture efficiency. Conceptual models for these two mechanisms are developed and compared with experimental data for particle removal and head loss. Model predictions indicate that particle removal by filtration through flocs is the mechanism that significantly enhances the filter performance.
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Acknowledgments
The research described in this paper was supported by the U.S. National Science Foundation under Grant CBET-0604566 and by the Sanjuan Foundation.
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Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 138 • Issue 4 • April 2012
Pages: 419 - 425
Copyright
© 2012. American Society of Civil Engineers.
History
Received: Jan 25, 2011
Accepted: Sep 16, 2011
Published online: Sep 19, 2011
Published in print: Apr 1, 2012
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