Bubble column reactors different spargers

Han, L., and Al-Dahhan, M.H. (2007), Gas-liquid mass transfer in a high pressure bubble column reactor with different sparger designs, Chemical Engineering Science, 62(1 -2) 131-139. 

In contrast to three phase fluid beds where the relation between the three phase hold-ups can be rather complex, in slurry reactors with the much smaller particles and slip velocities the relation between and is often simple as it is fixed by the feed ratio of solids and liquid phases, or liquid and solids volumes are constant (in batch systems). The bubble hold- up is much more difficult to predict, first of all because of the different regimes that might prevail both in stirred vessels and slurry sparger columns. These regimes are shared with two phase gas liquid systems (see fig. 4). In a three phase sparger the regimes are (see Shah [b]) ... 

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