The electro-deionisation is a process for continuous demineralisation of permeate from a reverse osmosis unit. An EDI module consists of several chambers that are separated by ion-selective membranes. The chambers are filled with ion exchange resin and placed between two DC voltage electrodes.

Particular advantages of this method are uninterrupted operation without need for chemicals. These units have a very small footprint. The EDI concentrate – concentrated RO permeate – does not require neutralisation; it can be recirculated within the unit or used for other purposes.

Features:

• Electro-deionisation with upstream RO unit » Diluate (product water) with typical conductivity < 0.2 μS/cm
• Continuous operation
• PR permeate recirculation included
• Piping in PVC and stainless steel » PLC instead of RO 1000 available as an option
• Wide range of options, such as membrane degassing, available to further lower dilute conductivity

Advantages: 

• Excellent product water quality due to downstream EDI (typical conductivity < 0.2 µS/cm)
• No chemicals required (unlike ion exchange plants, which require chemicals for regeneration)
• Ideal for applications with very strict requirements on permeate conductivity (e.g. clean steam and sterile steam generators, microelectronics, etc.)