Linear cooling of sodium sulfate batch crystallization

To obtain a unimodal crystal size distribution, linear cooling of a batch c rystallizer was experimentally examined. Sodium sulfate, which has a relati vely large heat of crystallization, was crystallized. The condition for batch crystallizer operation within the metastable region was derived : the product of temperature derivative of solute saturation c oncentration and cooling rate must be less than a certain value. Experiments were carried out with cooling rate satisfying the operation con dition. A nearly unimodal product of sodium sulfate was obtained.