Electrodeionization of water (EDI) is a modern and fully automated technology that allows to obtain demineralized water with very high quality parameters, so much required in the energy sector as well as in many other industries. Water that is demineralized in an EDI process is mainly used in hospitals, the pharmaceutical and cosmetics industries as feed water for high-pressure steam boilers. It is also used in electronics industry and energy sector.
Electrodeionization is a combination of two water treatment methods: electrodialisis (ED) and demineralization on ion exchange bed (DI). This combination eliminated the drawbacks of both processes, namely high electricity consumption in the electrodialisys process, the need to use chemical reagents and the formation of aggressive sewage in the case of ion exchange demineralization.
The EDI devices, we offer, use a special ion exchange resin, selective membranes and electric field to continuously remove ions from permeate, i.e. water pre-treated in the reverse osmosis process. EDI is a device that reduces the conductivity of water after the reverse osmosis to minimum levels, depending on the quality of the input water.
The EDI technology provides an autonomous and continuous regeneration process without the use of chemicals. The efficiency of the EDI process (the ratio of output stream to the input stream) is usually 90-95%. The concentrate from EDI can be turned back to the beginning of the treatment process or before reverse osmosis, or discharged into the sewage system. It can also be used for other purposes. Its quality is usually close to the quality of water before osmosis.
The EDI module is made of many chambers divided by cation- and anion- permeable membranes in a spiral system (cylindrical housing). The inlet water enters the module and is divided into the permeate and concentrate chambers. Under the influence of the electric field, the ions from water flowing through the permeate chamber, go through the cation- and anion-permeable membranes into the concentrate chambers.
The regeneration of ion-exchange resin is induced by water that in the permeate chamber loses other ions and under the influence of electric field is electrolyzed i.e. decomposition into H + hydrogen ions and OH- hydroxyl groups.
All EDI devices that we provide are equipped with a controller with an operator's control panel, power supply devices and a control and measurement apparatus for measuring such quantities as pressure, conductivity (external device) and flow.
Due to the fact that the electrodeionization is a fairly complex process and individual selection of technology should be performed each time, all technical and price data is available on request.