Gas holdup and interfacial mass transfer in gas-liquid tower contactors with ejector-type gas distributors

Abstract

The effect of decisive construction parameters of ejectors on gas holdup and on the rate of interfacial mass transport (characterized by kLa values) was studied in a gas-liquid tower reactor (I.D. 0.3 m) with an ejector (Venturi-tube type) gas distributor. The selected ejector characteristics included diffuser length and angle of diffuser walls inclination as well as nozzle type and geometry. Experimental data confirmed validity of our previously published conclusions on the relation between the rate of energy dissipation in the place of dispersion formation (i.e. in the ejector) and gas holdup and kLa values. The efficiency of dissipated energy utilization was however significantly influenced by the diffuser geometry. According to our experimental evidence the increase of ejector energy effectiveness with increasing diffuser length can be ascribed solely to its favourable effect on the gas suction rate while the mechanism of phases mixing (dispersion formation) in ejector was apparently independent of diffuser geometry within the whole range of experimental conditions.