Unveiling the enhancing potential of water pretreatment on energy efficiency in reverse electrodialysis systems- A comprehensive review

Reverse electrodialysis (RED) is a potential technology that exploits salinity gradients for power generation to face the increasing environmental issues and the need for sustainable energy solutions. To efficiently implement RED on a larger scale, pretreatment units are critical in limiting fouling effects, providing a path to increased energy density and overall efficiency. This paper aims to review the significance of water pretreatment in RED systems by increasing the power density. An analysis of the existing literature was performed in the SCOPUS database by Boolean Operators. Throughout this research, we observed pretreatment is one of the most critical phases for RED systems. Besides, many scientists are investigating ways to remove natural organic matter and scaling from water since previous studies have identified their adverse effects on power generation. Conventional pretreatment has proven to be enough to assist RED systems, but up to 45.6 % power density increase has been reported through non-conventional water pretreatment. Still, cost-effectiveness analyses, specific parameters, and acceptable thresholds to evaluate the RED applications' economic viability are lacking in the literature. Water pretreatment has immense potential for increasing RED performance, and ongoing studies are focused on developing them and scaling up to commercial scales.