There are two primary options to achieve deionization. Service Deionization (SDI) utilizes regenerable mixed-bed (cation/anion) resins with chemically bonded positive and negative charges. In the ion exchange process, the cation resins release hydrogen ions and the anion release hydroxyl ions. These ions bond creating a pure water molecule. Hydro's service DI resins are recycled and regenerated in a manner complying with use in pharmaceutical application. Our superior regeneration process and methods typically yield higher resistivity with lower TOC (Total Organic Carbon) re-introduction. Electrodeionization (EDI) is a continuously regenerating, low maintenance process utilizing cells containing ion exchange resins and membranes. DC electrical current is applied to the cell, causing a portion of water molecules to split into hydrogen (H+) and hydroxyl (OH-) ions. These ions attach to the cation and anion resin respectively, creating continuous regeneration while simultaneously deionizing the water. Contaminant ions are forced into a reject stream. EDI can be a cost effective alternative to service mixed-bed ion exchange.