Prediction and measurement of crystal size distributions for size-dependent growth

Predictions of size distributions, mean sizes and coefficients of variation in mixed-suspension mixed-product removal crystallizers are presented for the case when crystal growth rate is given by the expression G = G⁰ (1 + γL)^b as suggested by Abegg, Stevens and Larson (ASL). Crystal size distributions were measured at three scales of operation (1, 5 and 30 1.) for a system which exhibits size-dependent growth (potash alum/water). Experimental median sizes were in good agreement with the predictions and coefficients of variation significantly greater than 50% were obtained. The observed variation of crystal growth rate with size however was only moderately well represented by the ASL equation.