Purely Empirical Correlations Using Operating Parameters and Physical Properties

2 PURELY EMPIRICAL CORRELATIONS USING OPERATING PARAMETERS AND PHYSICAL PROPERTIES 

This approach was predominant in the early stages of studies on mass transfer in multiphase reactors. As an example, for the case of stirred reactors, several correlations of the following type were proposed  

Similarly, for bubble columns (two-phase sparged reactors), Sharma and Mashelkar (1968) proposed Equation 6.2 for the volumetric liquid-side mass transfer coefficient, based on measurements by the chemical method  

A singular lack of understanding of the hydrodynamics in the different multiphase contacting devices was the main reason for resorting to such decidedly empirical and system-dependent correlations. 

In majority of experimental investigations, overall volumetric mass transfer coefficients comprising the true mass transfer coefficient and the interfacial area are reported. To obtain the true mass transfer coefficient from such data, knowledge of the interfacial area is required. There is a wide variation in bubble/drop sizes in a 

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