Velocity and mass transfer coefficients

Wesselingh, J. A. Bollen, A. M. Single Particles, Bubbles and Drops Their Velocities and Mass Transfer Coefficients, Trans J ChemE, Vol 77, Part A, March (1999) 89-96... 

TABLE 2.3. Calculated Values of Electrolyte Velocity and Mass Transfer Coefficient... 

Early bubble models were too much idealized and therefore in conflict with observed facts, especially for large scale reactors. Also the predictive power of these models is limited. In recent models empirical relations are introduced for the three main factors determining the exchange between bubbles and dense phase bubble size, rising velocity and mass transfer coefficients. As the empirical relations have a limited range of validity, these models can often not replace general two phase models applied in combination with experimentally observed pareuneters. 

Azher, N.E., et al., 2005. Influence of alcohol addition on gas hold-up, liquid circulation velocity and mass transfer coefficient in a split-rectangular airlift bioreactor. Biochemical Engineering Journal 23 (2), 161—167. 

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