MODEL FOR LIQUID-LIQUID EXTRACTION COLUMN PERFORMANCE - THE INFLUENCE OF DROP SIZE DISTRIBUTION ON EXTRACTION EFFICIENCY.

A precise model for predicting liquid-liquid extraction column efficiency based upon assumed hydrodynamic, axial mixing and mass transfer behavior has been formulated and solved numerically. The complex nature of the dispersed phase can be better described by drop-size-dependent residence time distribution. Both the variation of axial velocities due to drops of different sizes, i. e. forward mixing, and the axial dispersion for the drops of the same size have been considered in this model. The computed results reveal that the effects of both varying velocities and dispersion of drops on extraction efficiency are appreciable and cannot be neglected, and the efficiency may be overestimated if only a forward mixing model is adopted. Refs.