Power Generation Performance of a Pilot-Scale Reverse Electrodialysis Using Monovalent Selective Ion-Exchange Membranes

Reverse electrodialysis (RED) is a promising process for harvesting energy from the salinity gradient between two solutions without environmental impacts. Seawater (SW) and river water (RW) are considered main RED feed because of their good availability. In Okinawa Island (Japan), SW desalination via reverse osmosis (RO) can be integrated with due to production large amount RO brine (concentrated SW, containing ~1 mol/dm3 NaCl), which usually discharged directly into sea. this study, pilot-scale stack, 299 cell pairs 179.4 m2 effective membrane area, was installed in plant. For first time, asymmetric monovalent selective membranes layer just at side were used as ion exchange (IEMs) inside stack. Natural model brines, well high-concentrate solutions. RW, fact surface study close plant, utilized low-concentrate solution. The power generation performance investigated by current-voltage (I–V) test showed maximum gross density 0.96 1.46 W/m2 respectively, when natural brine/RW used. These 50–60% improvement 0.62 0.97 generated respectively. approximate 50% more assigned suppression concentration polarization stack absence multivalent ions.