THE ALTERNATIVE TO ION-EXCHANGE RESINS
As an alternative to ion-exchange resins, electrochemical de-ionisation (EDI) can be used for residual water desalination. In the EDI, the classical ion exchange resin technology is coupled with modern membrane technology. A decisive advantage of EDI over the pure ion-exchange resins is that the option for continuous operation, because ion-exchange resins must be regenerated at regular intervals. During regeneration, water cannot be desalinated. However, an EDI system is regenerated during operation. This means that redundant design is not necessary for continuous operation of such systems.
Since the salt load with EDI is very low, a smaller partial current is required for waste-water and electrode cleaning. Consequently, the yield is hilgher when using EDI.
For efficient EDI operation, the carbon acid content in water must be as low as possible, therefore, we always recommend installing an carbon dioxide degassing unit before the EDI system.