The essence of effective characterization of crystallization kinetics and their successful application in crystallizer design and analysis resides in the recognition that all the kinetic events are rate processes. Although several kinetic events are identifiable in a crystallizer operation, crystallization kinetics in the literature are conventionally characterized in terms of two dominant rate processes occurring in a process of crystallization from solution, namely, crystal nucleation and growth. The terms rate and rate concept need careful definitions. At the outset it is necessary to emphasize the distinction between process rate and rate of change while establishing the kinetic correlations as has been suggested in the analysis of multiphase reactor systems (see, e.g., Bisio and Kabel, 1985). The process rate, as used in crystal nucleation or growth rate, is just a concept and is always important in process analysis. One does not measure process rate directly, but only arrives at its values by some combination of measurement and theory. The rate of change follows the dictionary definition as familiar from the calculus, has derivative character, and is subject to measurement.
KeywordsInterfacial Tension Mass Transfer Coefficient Nucleation Rate Effectiveness Factor Bulk Diffusion
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