Numerical Simulation of Gas-Liquid Two-Phase Flow in Zinc Electrowinning

doi:10.12068/j.issn.1005-3026.2015.08.016

Abstract

Abstract: The gas-liquid two-phase flows in zinc electrolytic cells with single plate and multiple plates were respectively numerically simulated with the commercial software of FLUENT. Based on the mechanism of the generation and movement of oxygen bubbles， the rising velocity of a single bubble was calculated. The results indicate that the rising velocity is 0.017m/s. With the effect of bubbles from the anode， the electrolyte near the anode flows upward and oppositely flows downward near the cathodes， forming a large recirculation zone in the cell. The average velocity of bubble cluster is 0.021m/s， which is consistent with the experimental data from the literature. In practical operation， with the joint action of the differential pressure and the bubble drag force， the recirculation of electrolyte flow can be enhanced remarkably. The average velocity of interelectrode fluid is 1.5 times higher than that under the bubble-free condition. This phenomenon indicates that the bubble movement can promote the refreshing of zinc electrolyte and restrain the dilution of zinc ions.

Key words: zinc electrowinning, gas-liquid flow, bubble, flow field, numerical simulation

CLC Number:

TF813

ZHOU Ping， LI Hao-lan， WEI Wen-wu ， SU Yin-biao. Numerical Simulation of Gas-Liquid Two-Phase Flow in Zinc Electrowinning[J]. Journal of Northeastern University Natural Science, 2015, 36(8): 1136-1140.

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