Dispersion Parameters and Effect of Impeller Speed, Holdup and Volume Fraction of Dispersed Phase on Separation Efficiency, Mass Transfer Coefficient of Dispersed Phase and Distribution Coefficient on Mixer-Settler Set

Document Type: Research Article


Faculty of Chemical Engineering, University of Tehran, Tehran, I.R. IRAN


An experimental study has been conducted on the hydrodynamics of a stage mixer-settler to obtain an appropriate design. In this paper several tests was performed to investigate full factorial design of experiments. Since each test was repeated seven times, the repeatability of the test was confirmed (P=1 bar and T=25 °C). Sauter diameter was determined by photographing both the mixer and settler in each test. The Sauter diameter was compared with the Calderbank model; finally, a model was suggested. Holdup quantity was measured by a vacuum pump at the end of each test. Another aim of this paper is the evaluation of separation mechanism under different impeller speeds and volume fractions. The effect of impeller speed in constant ratio of phases flow rate, and hold up are evaluated, and the effect of phase flow rate ratios in constant impeller speed on extraction efficiency, mass transfer coefficient and distribution coefficient were determined.


Main Subjects

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