2-PHASE COCURRENT DOWNFLOW IN PACKED BEDS

Cocurrent trickle flow was investigated in a 6-inch diameter column packed with 3/16-inch glass beads using N2 and MeOH. Liquid- and gas-phase residence-time distribution measurements were made, and for comparison with previous work were characterized by an effective axial dispersion coefficient and mean residence time. Radial variations in both liquid and gas velocity were small, and liquid holdup was in fair agreement with a literature correlation for countercurrent flow. Axial dispersion in both phases was considerably greater than in single-phase flow. Increased gas-phase dispersion was attributed to bridging of liquid on the packing. Liquid-phase behavior was satisfactorily described by a model which assumed exchange between free flowing and stagnant liquid. © 1969, American Chemical Society. All rights reserved.