Theoretical prediction of gas hold-up in bubble columns with Newtonian and non-Newtonian fluids

A theoretical model for gas hold-up in bubble columns with Newtonian and non-Newtonial fluids has been developed on the basis of the concept of a characteristic turbulent kinematic viscosity in bubble columns. Gas hold-ups in a 40-L bubble column and a 1000-L pilot plant fermenter with Newtonian fluids (water, glycerine, dextrose, and fermentation media) and non-Newtonian fluids((carboxymethyl) cellulose, carboxypolymethylene, and polyacrylamide) were measured. Predictions were compared with the present data and other experimental data and correlations available in the literature, over a wide range of conditions. A satisfactory agreement was found.