Performance Optimization Of Low Resistance Ion Exchange Membranes In An Electrodialysis-Evaporator Hybrid System For Reject Brine Treatment In Kuwait Desalination Plants

Author : Bader S AlAnzi

Abstract : This study aims to mitigate the environmental impacts of brine discharge generated from desalination plants. A pilot-scale electrodialysis–evaporator hybrid system was implemented as a cost-effective approach for treating reject brine. The electrodialysis unit employed a low-resistance membrane (LRM) to enhance salt production and low-salinity water recovery. The system consisted of an electrodialyzer with 25 cell pairs, incorporating monovalent selective anion exchange membranes (AEMs) and monovalent selective cation exchange membranes (CEMs), along with a neutral cell positioned at the cathode to limit fouling caused by the accumulation of divalent ions such as Ca²+ and K+. The system was evaluated under varying operating conditions, including current densities ranging from 300 to 500 A/m² and flow rates of 400 and 450 L/h. The results demonstrated that the low-resistance membrane achieved higher water recovery, reduced energy consumption, and more efficient monovalent ion removal compared to the high-resistance membrane. However, the permselectivity of the LRM for monovalent cations decreased with increasing current density, whereas the performance of the high-resistance membrane was less sensitive to current density variations. Furthermore, the inclusion of a neutral cell effectively minimized divalent ion accumulation on the inner cathode membrane

Keywords : Brine discharge, electrodialysis, density, resistance, recovery.

Conference Name : International Conference on Environment, Marine Resources, and Blue Economies in Oceania (ICEMRBE-26)

Conference Place : Kuwait City, Kuwait

Conference Date : 10th Mar 2026