Theoretical Prediction of Mass Transfer Coefficients in a Slurry Bubble Column Operated in the Homogeneous Regime
نویسنده
چکیده
The classical penetration theory was corrected and then applied for the semi-theoretical prediction of mass transfer coefficients kLa in a slurry bubble column operated in the homogeneous regime. The gas-liquid contact time was expressed as a ratio of bubble surface to the rate of surface formation. These terms were defined for the case of oblate ellipsoidal bubbles formed under homogeneous flow conditions. Six different liquid/solid systems (water/activated carbon, water/aluminium oxide, tetralin/aluminium oxide, 0.8 M sodium sulfate solution/kieselguhr (diatomaceous earth), ligroin (petroleum ether)/polyethylene and ligroin/polyvinylchloride) were considered. By means of the same correction factor (a single function of Eötvös number) as derived previously for gas-liquid bubble columns, 85 experimental kLa values were fitted with a mean error of 19 %.
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