Flow Pattern and Gas Hold-Up in Bubble Column with Liquid Jet Ejector

Abstract

An experimental study was performed on the flow pattern and gas hold-up in a bubble column with liquid jet ejector as the gas distributor.
At the spouting state under the condition of high liquid flow rate, two different flow regions existed in the column : the spouting section and the calm section. The spouting section was the lower region in the column and heavy liquid circulation existed there. The calm section was the upper region and constituted the uniform bubble flow regime. The border between the two sections was defined as the critical height which gave the variation point of the static pressure gradient, and was nearly three times the column diameter.
As liquid flow rate increased, gas hold-up in each section greatly increased and was influenced by the liquid characteristics concerning bubble coalescence. Empirical correlations of gas hold-up in each section were obtained by using Weber number based on the liquid velocity through the throat.