De Nora Water Technologies, Inc. offers the UAT™ EDI electrodeionisation system for the continuous and chemical free process of removing ionized and ionisable species from feed water. The UAT EDI system optimizes performance, maintains continuous product quality and can produce up to 15+ MÙ-cm high-purity water with high silica and boron rejection. The UAT EDI system is ideally suited for polishing reverse osmosis (RO) permeate, replacing conventional mixed bed ion exchange systems by eliminating the need to store and handle hazardous chemicals used for resin regeneration and associated waste neutralization requirements.

UAT EDI systems use a spiral wound membrane and ion exchange resins, sealed in a high strength FRP pressure vessel. An electrical current is used to force a continuous migration of contaminant ions out of the feed water and into the reject stream while continuously regenerating the resin bed with H+ (hydrogen) and OH- (hydroxyl) ions that are derived from water splitting. The flow process of the dilute and concentrate streams make the module completely unique. This flow design makes the UAT EDI modules more resistant to hardness scaling, allowing for higher hardness concentrations of the feed water (up to 2 mg/l as CaCO3) and reducing capital expenditures by routinely eliminating the need for softeners and/ or second pass RO.