Drop-Size Distribution and Dispersed Phase Hold-up in a Large Rotating Disc Contactor

Abstract

Abstract The effect of drop size and size distribution and the dispersed-phase hold-up on the performance of an extraction column are the most important hydrodynamic characteristics, because under steady operating conditions, drop size and hold-up are proportional to the interfacial area. Correspondingly, the efficiency of mass transfer is a function of drop size as well as hold-up. A number of experimental investigations using the rotating disc contactor (RDC) have reported the measurement of dispersed-phase hold-up, drop size, and size distribution. However, most of the published data are for very small RDCs of <7.5-cm diameter. All the correlations introduced to describe the column hydrodynamics give unreliable results when applied to large-scale RDC operation and with different systems to those studied. Therefore, RDC hydrodynamics in the absence of mass transfer have been studied on a 450-mm-diam column, 4.3-m high, and the results obtained have been compared with those reported previously from small...