Axial and Radial Gas Holdup in Bubble Column Reactor

Abstract

Bubble column reactors are considered the reactor of choice for numerous applications including oxidation, hydrogenation, waste water treatment, and Fischer-Tropsch (FT) synthesis. They are widely used in a variety of industrial applications for carrying out gas-liquid and gas-liquid-solid reactions. In this paper, the computational fluid dynamics (CFD) model is used for predicting the gas holdup and its distribution along radial and axial direction are presented. Gas holdup increases linearly with increase in gas velocity. Gas bubbles tends to concentrate more towards the center of the column and follows a wavy path.

Effects of Swirl Bubble Injection on Mass Transfer and Hydrodynamics for Bubbly Flow Reactors: A Concept Paper

“…Mixing time also can be decreased with increasing the gas velocity [12]. The gas bubbles tend to concentrate more in the central core of the column, which causes an increase in liquid circulation [13]. Bubble column with perforated plate distributors causes a swarm of bubbles to rise through the liquid and this gives an agitation effect to the liquid phase.…”

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