Numerical analysis on optimal zone lengths for each pass in multipass zone‐refining processes

Abstract

Abstract The effect of zone length on the separation efficiency in multipass zone‐refining processes has been investigated theoretically. The optimal zone length for maximum separation efficiency in each zone pass has been determined. As a well known fact (Davies, 1959), the best performance in the first pass is achieved by normal‐freezing operation. In multipass operations, the optimal zone lengths in each pass and their corresponding maximum fraction of solute removal were obtained with distribution coefficients k and number of passes n as parameters. The results showed the optimal zone lengths for all passes increase with distribution coefficient, but decrease with pass number.