Experimental study of growth kinetics in a new freezing-based pretreatment for desalination using Reverse Osmosis

This work conducts an experimental study of the operational parameters influencing the freeze-based pretreatment process, to improve the efficiency of reverse osmosis (RO) desalination. The effects of the temperature gradient (7 and 9 °C), subcooling degree (1.25 and 1.75 °C), and initial salt concentration (35 and 50 g/kg) on the ice growth rate were investigated using a dynamic-layer crystalliser. The findings show that an increased initial salt concentration and a higher subcooling degree lowered the growth rate, whereas a higher temperature gradient enhanced it. These results align with the existing knowledge of crystal formation and demonstrate the potential efficacy of freezing as a pretreatment in hybrid desalination systems.