Brittle fracture in crystallization processes Part B. Growth of fragments and scale-up of suspension crystallizers

In chemical engineering processes in which solids are produced or handled, the strength of the substance plays a key role. The following presents a co mprehensive model for one of these processes, crystallization from suspensi ons. When crystallization kinetics are determined by the formation of fragm ents and their subsequent growth, the developed model equations can predict the whole crystallization process in a quantitative manner. The size depen dent growth behaviour of fragments is explained by the attrition process it self. The predicted influence of material properties on the fracture behavi our of a greater number of crystalline substances as well as the suggested growth function for attrition fragments compare well with experimental resu lts. The model equations can be used to estimate when and how brittle fract ure will occur in chemical engineering processes and, more specifically, to scale-up suspension crystallizers. (C) 1999 Elsevier Science Ltd. All righ ts reserved.