Programmed cooling of batch crystallizers

Abstract A method is presented for the calculation of optimum cooling curves based on a simple mathematical description of the individual kinetic processes involved in a crystallization operation. Cooling curves for two different substances, computed on an IBM 360, have been utilized in an experimental study on two laboratory-scale crystallizers with aqueous solutions of potassium sulphate and ammonium sulphate. The temperature controller, which uses a perforated paper tape programme, is described in detail. The results show that the programmed cooling brings about a significant increase in the size and an improvement in the quality of crystals from a batch crystallizer.