Variation of drop size and hold-up in a dense-packed dispersion

Abstract

Allowing for the effect of binary coalescence, the increase in drop diameter and hold-up in a dense-packed dispersion can be expressed as exponential functions of vertical height. Data from five different liquid-liquid systems in which either the aqueous or organic phase is dispersed were used to verify these relationships. Furthermore, empirical expressions are also developed which predict the initial hold-up and final drop diameter in terms of the initial drop diameter, physical properties and operating conditions. From these expressions the interfacial coalescence time and variation in binary coalescence time can be readily obtained. The correlations are successfully used to predict the initial drop diameter and variation in hold-up for published data on an industrial system.