Stack Design and Operation for Scaling Up the Capacity of Flow-Electrode Capacitive Deionization Technology

Abstract

Flow-electrodes have recently been studied for use in capacitive deionization applications because of their continuous and high desalting efficiency. The production capacity of desalinated water in the FCDI system is limited compared to infinite ion capacity of the flow electrodes due to restrictions in the flow-rate of the influent/effluent. Therefore, we designed and fabricated an FCDI stack with 5 unit cells in order to increase the production capacity of desalinated water.Through inlet pressure measurements of the flow-electrodes in the FCDI stack, we confirmed that the flow-electrodes were uniformly segmented from the manifold formed in the FCDI stack into the flow channels of each unit cell. We also confirmed that there was no pressure increase at the flow-electrode in the flow channel caused by the increase in the number of unit cells in the FCDI stack. Also, the FCDI stack showed similar desalting efficiency when compared to that of the FCDI unit cell. On the basis of the results, we verified that the FCDI stack can be successfully used to scale up the desalinated water production capacity of the FCDI system.

Efficient Capacitive Deionization Using Thin Film Sodium Manganese Oxide

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Current to Clean Water – Electrochemical Solutions for Groundwater, Water, and Wastewater Treatment

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