Analysis of EDI working principle
This equipment is produced and exported by Wenzhou Haidoneng Environmental Protection Equipment Technology Co., Ltd. It is a 6 ton automatic two-stage reverse osmosis with softening belt and EDI super pure deionized water equipment.
1. EDI membrane stack is composed of a certain number of elements sandwiced between two electrodes.Each unit is composed.Within each cell are two different types of chambers: fresh water chambers to be desalted and concentrated water chambers to collect the removed impurity ions.The fresh water chamber is filled with a mixture of positive and anion exchange resins between two membranes: a cation exchange membrane that allows only cationic penetration and an anion exchange membrane that allows only anion penetration.Resin bed by using dc on opposite sides of the chamber for continuous regeneration, voltage causes the water molecules in the water into H + and OH -, these ions in the water by the corresponding electrode, through the anion and cation exchange resin on the corresponding membrane in the direction of migration, when the ion exchange membrane into the thick chamber, H + and OH - combine to form water.This H+ and OH- generation and migration is the mechanism of the resin to achieve continuous regeneration.
2. When impurity ions such as Na+ and Cl- in the water are adsorbed to the corresponding ion exchange resin, these impurity ions will undergo the same ion exchange reaction as in the ordinary mixing bed, and the corresponding replacement of H+ and OH-.Once impurity ions in the ion exchange resin are added to the H+ and OH- migration towards the exchange membrane direction.These ions will continuously pass through the resin until they pass through the exchange membrane and enter the concentrated water chamber. Due to the blocking effect of the exchange membrane of the adjacent compartment, these impurity ions cannot further migrate to the direction of the corresponding electrode, so the impurity ions can be concentrated in the concentrated water chamber, and then the concentrated water containing the impurity ions can be discharged out of the membrane stack.