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Volume 63, Issue 2

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Effects of vessel baffling on the drawdown of floating solids

Joanna Karcz
  • Department of Chemical Engineering, Szczecin University of Technology, al. Piastow 42, PL-71 065, Szczecin, Poland
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/ Beata Mackiewicz
  • Department of Chemical Engineering, Szczecin University of Technology, al. Piastow 42, PL-71 065, Szczecin, Poland
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Published Online: 2009-02-11 | DOI: https://doi.org/10.2478/s11696-009-0011-0

Abstract

The effects of baffling of an agitated vessel on the production of floating particles suspension are presented in this paper. Critical agitator speed, needed for particles dispersion in a liquid agitated in a vessel of the inner diameter of 0.295 m, was determined. The just drawdown agitator speeds were defined analogously to the Zwietering criterion. Specific agitation energy was calculated from the power consumption experimental data obtained by means of the strain gauge method. The experiments were carried out for twelve configurations of the baffles differing in number, length and their arrangement in the vessels. The following high-speed impellers were used: up- and downpumping six blade pitched blade turbines, Rushton turbine, and propeller. The impeller was located in the vessel in the height equal to two-thirds or one-third of the vessel diameter from the bottom of the vessel. The results were described in the form of a dimensionless equation.

Keywords: agitation; floating particles; baffling

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About the article

Published Online: 2009-02-11

Published in Print: 2009-04-01


Citation Information: Chemical Papers, Volume 63, Issue 2, Pages 164–171, ISSN (Online) 1336-9075, DOI: https://doi.org/10.2478/s11696-009-0011-0.

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