Fouling and process design in reverse electrodialysis: a study with natural waters

Summary

To include renewable energy in the energy matrix can be a challenge for many societies. Blue energy is a promising energy source that uses the controlled mixing of the salinity gradient between fresh and sea water to produce electrical energy. Reverse Electrodialysis (RED) is a process that allows to harvest this energy. It uses a series of alternating membranes, which unfortunately can suffer from fouling, decreasing the overall power output that can be harvested. Fouling in RED can be present in diverse ways, and mitigation options are needed to alleviate its effect. In this project, the use of pre-treatment for the feed waters and cleaning strategies that can recover the lost performance were studied and possibilities were presented to overcome the issues with fouling. This allows RED technology to be used for longer time and produce more energy, becoming more relevant in the energy matrix context.