Hydrodynamics of a non-aqueous system in a packed liquid extraction column

Abstract

Dispersed phase holdup, flood point and droplet size data have been obtained for the effectively non-aqueous system Sulfolane-heptane in a 75 mm diameter column packed with random Raschig rings. The holdup results showed distinctly different behaviour from that of aqueous systems, giving a characterstic velocity plot that was concave upwards, indicating an increasing droplet velocity at higher holdup values. The flood-points were correspondingly higher than would be predicted for an aqueous system. These results were explained in terms of a droplet 'chain flow', which would lead to a reduced drag force. A modified correlation for holdup is proposed which incorporates the Morton number and gi..