GAS PHASE FLOW PATTERNS IN A BUBBLING COLUMN

Abstract

The gas phase flow patterns in a bubbling column were investigated, using tracer methods to establish the residence time distribution. An analogue computer obtained the moments of this distribution directly. The air flow rate and column height were varied. The results showed that as the air flow rate increased, although the voidage increased, the mean residence time decreased. Thus an increasing proportion of the gas phase behaved as a stagnant volume. The results are correlated in terms of a mixed region model. Other work showed that an Increase of liquid viscosity, or the inhibition of coalescence, affected only the stagnant volume. The rate of coalescence was investigated and an estimate of its magnitude was obtained.