Intensification of mass transfer in a pulsed bubble column

The application of liquid pulsations to a classic bubble column substantially changes the hydrodynamics of bubble flow and the process of mass transfer. The paper presents a wide range of experimental results concerning the intensification of mass transfer in a pulsed bubble column of square cross section with side D = 0.135 m and slenderness ratio H-p/D ranging from 3 to 14.5. Experimental measurements were carried out at a frequency ranging from 1 to 70 Hz and the amplitude of a disk vibration exciter from 0.25 to 2 mm. The effect of liquid pulsation and volumetric gas flow rate on gas hold-up epsilon(G), mass transfer coefficient k(L)a and free liquid surface deflection Y-i was investigated. It was shown that the application of pulsations to a bubble column caused a significant increase of gas hold-up and mass transfer coefficients. Based on the experimental results correlation equations for gas hold-up and mass transfer coefficient in a bubble column (with and without pulsations) were proposed and confirmed experimentally with an accuracy of +/- 15% and +/- 25%, respectively. A simple method in the form of a diagram has been proposed to determine optimal operating conditions of a pulsed bubble column. (C) 2016 Elsevier B.V. All rights reserved.