부산대학교 도서관

Flow electrodes-based capacitive deionization (FCDI) is a highly energy-efficient desalination processcompared to conventional processes, including reverse osmosis and multi-stageflash distillation. Furthermore, it provides a continuous desalinationflow with high salt-removal capacity, whereas CDIusingfixed electrodes requires additional electrode rinsing. In FCDI, salt ions are adsorbed ontoflowcarbon electrodes and stored in the electrode slurry container, which is similar to an electrochemicalflowcapacitor. Therefore, stored ions can generate energy during discharging in FCDI operation. In this study,such energy generation was systematically investigated in terms of the various discharging rates, feedconcentrations, and volume offlow-electrode slurry. We found that the results were correlated with thechanges in the salt concentration of the effluentflow. The discharging current of 50 mA showed thehighest capacity for energy generation out of all the experimental conditions; it recovered around 25% ofthe energy consumed during FCDI desalination. We believe that such energy recovery can greatly reducethe energy consumption needed for FCDI desalination. Such recycling of generated energy would makeFCDI more attractive than other conventional desalination techniques.