Computational Study of Particle-Eddy Interaction in Sedimentation Tanks
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Volume 130, Issue 1
Abstract
Sedimentation tanks are used in the process industry to separate the solid particles from the slurry to get the clarified liquid. A detailed study of the hydrodynamics of sedimentation tanks is presented here using an Eulerian-Lagrangian approach to study the motion of solids in the tank. The model, in its present form, is applicable only to nonflocculent discrete (Type I) settling. It is shown that a typical particle-eddy interaction can be characterized by a lower cut-off size below which the particles would be entrained by the eddy; and an upper cut-off size above which the particle would continuously settle through the sedimentation tank in spite of the recirculation. The effect of inlet configuration on the flow field as well as on the settling characteristics has been investigated. The simulations show that both the upper and the lower cut-off sizes for a sedimentation tank are considerably reduced by providing a tulip type of inlet with a conical deflector as compared to a straight inlet.
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Information
Published In
Journal of Environmental Engineering
Volume 130 • Issue 1 • January 2004
Pages: 37 - 49
Copyright
Copyright © 2004 American Society of Civil Engineers.
History
Received: Aug 28, 2001
Accepted: Jun 4, 2002
Published online: Dec 15, 2003
Published in print: Jan 2004
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