Formation of 'Bubble Bunch' in a Low Interfacial Tension Gas-Liquid System: A Phenomenological Study

摘要

While studying the operation of a bubble column, it was observed that under some circumstances tiny bubbles attach to bubbles with bigger size without coalescing to them. In other words, bubbles with large diameters (d>5mm) swept tiny bubbles (d<1mm) in their way to the top of the column and form grapes of bubble.We named this phenomenon "bubble bunch" and discussed the effect of it on total gas hold-up and interfacial area. It was found that although it has almost no affect on gas hold-up, it can increase the interfacial area up to 10% more than what is anticipated by correlations in the literature. The process of film thinning was modelled for this phenomenon and critical film thickness was calculated as a function of interfacial tension.