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Settling behaviour of heavy and buoyant particles from a suspension in an inclined channel

Published online by Cambridge University Press:  21 April 2006

David Hin-Sum Law
Affiliation:
Alberta Research Council, Energy Resources Division. Oil Sands Research Department, Edmonton, Alberta, Canada
Robert S. Mactaggart
Affiliation:
Department of Chemical Engineering, University of Alberta, Edmonton, Alberta, T6G 2G6, Canada
K. Nandakumar
Affiliation:
Department of Chemical Engineering, University of Alberta, Edmonton, Alberta, T6G 2G6, Canada
Jacob H. Masliyah
Affiliation:
Department of Chemical Engineering, University of Alberta, Edmonton, Alberta, T6G 2G6, Canada

Abstract

Settling characteristics of bidisperse suspensions containing light and heavy particles in inclined channels have been studied both experimentally and theoretically. The suspension is relatively dilute with a total volume fraction of no more than 0.16. In this dilute range the flow-visualization experiments indicate the formation of distinct zones with clear interfaces between them. There is no evidence of lateral segregation of particles. The convection currents formed near an inclined boundary are transferred to different zones depending on the relative concentration of the two species. Based on the flow-visualization experiments, the well known Ponder-Nakamura-Kuroda (PNK) model has been adopted to predict the settling characteristics of bidisperse suspensions.

Type
Research Article
Copyright
© 1988 Cambridge University Press

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