Estimation of bubble size in flotation columns

Abstract A non-iterative procedure for the estimation of bubble size in flotation columns is presented. In a bubble swarm, the bubble terminal rise velocity is estimated using an appropriate drift flux relation which depends on the frother type. For Dowfroth 250C, MIBC and Triton X-100, these drift flux relation were found to be those of Marrucci [1], Turner [2], and, Richardson and Zaki [3] respectively. By using dimensionless groups in the correlation procedure, dimensionally consistent correlations are presented. The analysis shows that in the presence of frothers, the drag coefficient of the air bubbles increases. This is attributed to surfactant adsorption at the gas-liquid interface.

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