1 Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, QC, Canada, H3G 1M8; Laboratory Desalination and Natural Water Valorization, Center of Water Research and Technology, BP273, Soliman, 8020, Tunisia. Electronic address: kha.touati@gmail.com.

Effective brine management remains a major challenge for the desalination industry, particularly as plants encounter increasingly high-salinity waste streams. This study presents a comparative performance assessment of advanced reverse osmosis-based technologies, low-salt-rejection reverse osmosis (LSRRO), high-pressure reverse osmosis (HPRO), osmotically assisted reverse osmosis (OARO), and cascading osmotically mediated reverse osmosis (COMRO), alongside mechanical vapor compression (MVC) for treating saline brines across a wide concentration range. Key performance indicators including water recovery, specific energy consumption, and levelized cost of water (LCOW) were analyzed to identify operational limits and economic feasibility. Results show that membrane-based processes (LSRRO, HPRO, OARO, and COMRO) perform most efficiently at moderate salinities (C < 1.2 M), achieving recoveries =60 % with relatively low energy consumption. Beyond this threshold, HPRO and LSRRO experience sharp performance declines, whereas OARO and COMRO maintain stable recovery and energy profiles up to ~2 M. At higher concentrations (2-4 M), only OARO and COMRO remain technically viable, though with reduced recoveries (~25 %) and increased energy demand. For hypersaline brines (>4 M), all membrane processes become limited by excessive osmotic pressure and declining recovery, leaving MVC as the only viable option, despite its substantially higher energy consumption (15-25 kWh/m³) and LCOW. These comparative insights highlight clear salinity-dependent applicability windows: LSRRO and HPRO for moderate salinity, OARO and COMRO for high salinity, and MVC for extreme hypersalinity. The results provide practical guidance for technology selection based on feed salinity and operational priorities and underscore the need to develop hybrid and renewable-energy-integrated systems to improve the sustainability of high-salinity brine management.