Liquid circulation, gas holdup and pressure drop in bubble column with draught tube

Abstract

The effects of gas velocity and geometrical dimensions of apparatus on the flow rate QLof circulating liquid, gas holdups and pressure drops in bubble columns with draught tube were examined. It was found that QLincreases with increasing gas velocity, column diameter, draught tube length, and height of the lower end of draught tube, and decreases with increasing liquid viscosity. It was also found that the maximum value of QLis observed for constant values of gas velocity and column diameter, when the diameter ratio of draught tube and column is about 0.6. Empirical equations for gas holdups in draught tube and annulus and the pressure drops due to flow reversals, necessary for estimating QL, are proposed. © 1984, The Society of Chemical Engineers, Japan. All rights reserved.