This article describes the development of a model for the processes of crystal layer growth and sweating in static melt crystallization (SMC). Model foundations and fractal porous media theory were introduced from models of falling film melt crystallization (FFMC). Consistent simulation results were obtained for this model without using a fitting parameter. A systematic comparison of SMC and FFMC was conducted to reveal the advantages and disadvantages of separation in these two melt crystallization modes. The resulting models were used to optimize key operational profiles in FFMC and SMC. The average effective distribution coefficients (K-eff) over bar of calcium and sodium ion impurities were determined to be 0.03 and 0.025, respectively, for a combined FFMC and SMC operation. The separation potential of melt crystallization is being explored using various models and simulations for application in the industrial preparation of ultrapure chemicals. (C) 2014 Elsevier Ltd. All rights reserved.