Conventional and AWT Mixed-Liquor Settling Characteristics
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Volume 127, Issue 3
Abstract
Settling characteristics of mixed liquor from seven advanced wastewater treatment (AWT) and two conventional wastewater treatment facilities in the Tampa Bay Metropolitan Area were evaluated. An algorithm was developed that relates zone settling velocity (Vs) of the mixed liquor to initial mixed-liquor suspended solids (MLSS) concentration and unstirred sludge volume index (uSVI) of the mixed liquor. Two-tailed, paired comparison, Student's t-tests indicated there was no significant difference between the sludge volume index (SVI) as measured in a 1 L unstirred graduated cylinder and that measured in a stirred, 28 L Plexiglas column. A secondary clarifier operating diagram is presented that can be used by engineers and operators in the design and operation of secondary clarifiers. Bye and Dold's model could be used to predict the SVIs of the mixed liquors evaluated in this study.
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Received: Dec 16, 1999
Published online: Mar 1, 2001
Published in print: Mar 2001
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