A correlation for gas holdup in turbulent coalescing bubble columns

Abstract

A review of existing literature for the purpose of comparing correlations which allow the explicit predictiosn of gas holdup in two‐ or three‐phase bubble columns shows wide disagreement concerning the effect of various variables. Further, various correlations, apparently of equal validity, show equally wide disagreement in the predicted absolute values of gas holdup among three test systems; water‐air, hydrocarbon solvent—air, and trichloroethytene air. Some possible reasons for these disagreements are discussed.Extensive gas holdup data obtained in a 0.30 m diameter column for the three test systems were correlated statistically for the transition and the turbulent region. The resulting correlation gives agreement with experiment to within ±20%, with most data showing ± 10% agreement. The proposed correlation was also tested against thirteen data sets (from eight researchers) which corresponded to its region of validity and gave good agreement. Three additional relevant data sets were not satisfactorily predicted.