Apparatus for Observation and Analysis of Floc Blanket Formation and Performance
Publication: Journal of Environmental Engineering
Volume 140, Issue 1
Abstract
Floc blankets are fluidized beds of aggregated suspended particles utilized in some upflow sedimentation tanks for drinking water treatment. Floc blankets can significantly enhance particle removal and may reduce operation and maintenance costs. An experimental apparatus was built with the goal of developing an understanding of floc blanket physics and to establish a mechanistic basis for optimizing floc blanket performance. Visual insights into floc blanket mechanics are obtained by analyzing transmitted light intensity through a 1.3-cm-thick section of a floc blanket. Floc blankets were formed under simulated raw water conditions of 100 nephelometric turbidity units (NTU), an alum coagulant dose of ( as Al), and at sedimentation tank upflow velocities ranging from 0.4 to . This study presents nondestructive methods for measuring floc blanket concentration and position of the floc-water interface, steady-state performance data from the experimental apparatus, and the effect of upflow velocity on solids concentration in a floc blanket.
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Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 140 • Issue 1 • January 2014
Pages: 11 - 20
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Aug 31, 2012
Accepted: Aug 12, 2013
Published online: Aug 14, 2013
Published in print: Jan 1, 2014
Discussion open until: Jan 14, 2014
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