GAS HOLDUP PROFILES WITHIN ANNULAR SECTIO N IN A DOUBLE TUBE BUBBLE-COLUMN

Effects of the gas velocity and the ratios of outer/inner column diame ter on the values of local gas holdup in a double tube bubble column w ere experimentally studied. The local gas holdup in the annular sectio n was measured by means of a conductivity probe technique. The maximum value in the radial profile of gas holdup and the mean gas holdup inc reased with increasing superficial gas velocity, while they were hardl y affected by the ratios of outer/inner column diameter within the ran ge of the present experiment. Based on the velocity profile of fluid i n laminar flow, modeling the gas holdup profile in the annular section was carried out. The results calculated by the experimental equation agreed well with the measured data for the radial profiles of the gas holdup.