Electrolytic Ion Exchange System EDI

The electrodialysis EDI system can remove ions from water solutions. It is usually used in conjunction with reverse osmosis RO and other purification equipment. Therefore, our high-quality modules can continuously produce ultra-pure water with a resistivity of up to 18.2 MΩ/cm. Thus, EDI can operate continuously or intermittently. Therefore, electrodialysis is an environmentally friendly solution for ion removal.

What is the electrodialysis system?

Firstly, electrodialysis EDI is an electro-driven water treatment technology. Therefore, it uses electricity, ion exchange membranes, and resins to remove ionized substances from water.

What substances does the electrodialysis EDI system remove from water?

The electrodialysis EDI system removes ions and other charged substances from water, such as salts and organic acids.

How does the electro-dialysis EDI system work?

The EDI system module consists of a group of containers. Therefore, we fill the containers with ion exchange resins and separate them with ion exchange membranes. This way, water enters the module, where a perpendicular electric field applied here forces ions to pass through the resin and the membrane. These impurity ions do not permanently combine with the medium. Instead, the system collects them in the concentrated liquid flow, which is then discharged or recycled. You can directly use the deionized product water or further treat it to increase the purity of the water.

The EDI module actually acts as an ion exchange bed and continuously regenerates through electrical energy. This process occurs when ions pass through the resin layer and move between the selective membranes for cations or anions. Therefore, the electro-dialysis EDI system exchanges H+ and OH- ions. So, the ions that combine with the ion exchange resin eventually migrate to a separate chamber. Under the influence of the externally applied electric field, this also generates the necessary H+ and OH- ions for maintaining the resin in a regenerated state. The ions in the individual chamber are discharged to the waste liquid by the system.

At the same time, the limitations of the ion-exchange ion penetration EDI system are different from those of traditional ion exchange or reverse osmosis systems. Additionally, the ion purity of the produced water is basically limited by the total number of ions absorbed by the resin. Therefore, the upper limit of the ion arrival rate limits the performance of EDI. Excessive ion loading often causes the module to overload. So, we usually use EDI after reverse osmosis, and if the water quality is very hard, degassing to remove carbon dioxide is also performed. Moreover, if you have more questions about the Huaxin  water treatment system, please contact us.