Electrodeionization (EDI) is a process that uses ion exchange resins to absorb

 ions from a dilute water stream and then transports the absorbed ions through

 ion-exchange membranes into a concentrate water stream under the influence

 of an applied electro field. In the process,ion exchange resins do not need to 

regeneration via acid or alkali. This new technology could replace traditional

 Electrode ionization (DI) equipment, product ultrapure water whose resistance up to 18 MΩ·cm.

Advantages of EDI technology

A mixed bed ion exchange unit has to be regenerated by using acid and alkali, 

but an EDI system does not need such a process. This is the fundamental advantage

 of EDI technology over the conventional ion exchange technology. However, this

 advantage can be expressed into other aspects as listed below.

1. EDI process does not consume regeneration chemicals.

2. EDI process does not create waste water and much more environmental.

3. EDI systems do not require shutdown for regeneration.

4. EDI systems are smaller than mix bed ion exchange units.

5. EDI process provides water of consistent quality.

6. Operating expenses are lower than ion exchange units.

Applications of EDI technology

EDI typically may be used in any applications that require ultrapure water at a resistivity 

above 1 MΩ·cm. The typical industries that use ultrapure water include:

1. Microelectronic and semiconductor production.

2. Pharmaceutical and biomedical industries.

3. Chemical production.

4. High pressure boiler such as the ones in power plants