Modeling and control of a semi-batch cooling seeded crystallizer

We present a mathematical model of semi-batch cooling seeded crystallization of alpha-lactose monohydrate. The crystallization dynamics are described by population, mass and energy balance equations including the phenomena of nucleation (crystal birth) and growth. After developing the model we present two optimal control studies, where control of temperature and feed rate are used to increase the number of particles in a given narrow target size range. We compare our results obtained by optimal control with those obtained by heuristic strategies as often recommended in the literature.