Sludge Floc Behavior in an Elongated Rectangular Settling Tank
Publication: Journal of Environmental Engineering
Volume 135, Issue 11
Abstract
The different sludge floc distributions along the rectangular secondary settling tank were confirmed experimentally. Along the settling tank, three different regions can be formed: the fast settling zone near the inlet, the compaction zone in the middle, and the slowly settling zone near the outlet. Further investigation of morphological change of sludge flocs also showed corresponding floc characteristics: the bigger size of particles in the front, the relatively smaller particles with high density in the middle, and the small loose flocs in the rear. These were determined by the hydraulics and floc construction. The preceding results can be used as a guide to design systems to collect loose sludge solids.
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Acknowledgments
The preparation of the paper was supported by a grant from the Eco-Star Aquatic Ecosystem Restoration Research Program.UNSPECIFIED
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Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 135 • Issue 11 • November 2009
Pages: 1206 - 1212
Copyright
© 2009 ASCE.
History
Received: Sep 12, 2008
Accepted: Mar 18, 2009
Published online: Mar 25, 2009
Published in print: Nov 2009
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