Correlations airlift reactor

Airlift reactors, 15 703-709, 726-727 gas-liquid volumetric mass transfer coefficient correlations for,... 

Gas-liquid volumetric mass transfer coefficient correlations, for airlift reactors, 15 704-705t Gas lubrication, 15 252 Gas mantles cerium in, 5 689 thorium in, 24 757 Gas masks, 5 832-835 Gas meter provers, liquid displacement, 11 652... 

No general correlations for Aj a are available for EL airlift reactors. However, it has been suggested [28] that, before a production-scale airhft reactor is built, experiments are performed with an airlift that has been scaled down from a production-scale airhft designed with presently available information. The final production-scale airlift should then be designed with the use of the experimental data acquired from the scaled-down airhft reactor. 

However, for a given gas velocity, any change in gas or liquid properties, downcomer and riser geometry, phase separation conditions, liquid volume, reactor height, or gas distribution causes changes in liquid velocity and gas holdup. Therefore, no generalized model or correlation for the volumetric gas-liquid mass transfer coefficient in airlift reactors exists. 

In the case of airlift reactors, the flow pattern may be similar to that in bubble columns or closer to that two-phase flow in pipes (when the internal circulation is good), in which case the use of suitable correlations developed for pipes may be justified [55]. Blakebrough et al. studied the heat transfer characteristics of systems with microorganisms in an external loop airlift reactor and reported an increase in the rate of heat transfer [56], In an analytical study, Kawase and Kumagai [57] invoked the similarity between gas sparged pneumatic bioreactors and turbulent natural convection to develop a semi-theoretical framework for the prediction of Nusselt number in bubble columns and airlift reactors the predictions were in fair agreement with the limited experimental results [7,58] for polymer solutions and particulate slurries. 

Trilleros, J., Diaz, R., and Redondo, R (2005), Three-phase airlift internal loop reactor Correlations for predicting the main fluid dynamic parameters, Journal of Chemical Technology <6 Biotechnology, 80(5) 515-522. 

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