MODELING OF GROWTH-RATE DISPERSION IN BATCH COOLING CRYSTALLIZATION

The influence of growth rate dispersion on the product-size distribution of batch cooling crystallization is investigated by computer simulations. The model accounts for primary and magma density-dependent secondary nucleation, and growth rate dispersion of the constant crystal growth type. The model is solved by a combination of the method of characteristics and moment analysis, by which the entire product-size distribution is recovered. The study includes three different growth rate activity distributions, and the influence of the corresponding coefficient of variation is analyzed for unseeded and seeded processes. The results show that the effect of growth rate dispersion on the crystal-size distribution may be significant even at moderate dispersion. At high dispersion, even the actual shape of the growth rate activity distribution may become important.