A succinct review of the treatment of Reverse Osmosis brines using Freeze Crystallization

In recent years, various Freeze Crystallization (FC) processes have been investigated and shown to have potential as an environmentally friendly and sustainable water treatment technology towards achieving a near zero waste by producing potable water and salts (in some instances pure salt(s)) from hyper-saline brines.This paper reviews the history and current status of FC technologies for the treatment of Reverse Osmosis (RO) brines. A number of water treatment examples and applications of FC are discussed. The review found that, although the outcomes from the FC research are promising, the adoption of this technology in mainstream desalination brine treatment has been insignificant despite the fact that FC could have niche applications in the treatment of brines generated from membrane processes such as RO. The review also found that a hybrid technology approach, such as an integrated RO-FC process, can provide the optimum treatment solution from both an equipment capital and operating cost perspective. Lastly, the paper highlights future focus areas for research and development in the field of FC that aims at making this technology part of the mainstream suite of brine treatment technologies.