EDI (Electrodeionization) technology is a combination of electrodialysis technology and ion exchange technology. The selective permeation of anion and cation by anion and cation exchange membranes and the exchange of ions by ion exchange resins are realized under the action of DC electric field The directional migration of ions completes the deep desalination of water. At the same time, the hydrogen ions and hydroxide ions generated by the ionization of water regenerate the ion exchange resin, so ultra-pure water can be continuously produced without acid-base chemical regeneration.
How EDI works
1. The RO produced water is evenly distributed into the fresh water chamber after entering the EDI module.
2. The trace ions not removed by the RO membrane are adsorbed on the membrane surface by the ion exchange resin in the fresh water chamber.
3. Direct current is applied to the electrodes at both ends of the ED I module to drive the anions and cations in the fresh water chamber to the corresponding electrodes to migrate to the concentrated water chamber, thereby preparing high-purity water.
4. Under the action of the electric field, water molecules are ionized into H + and OH- in a large amount, thereby continuously regenerating the ion exchange resin.