Mixed Bed Resin Electroregeneration

Electroregeneration of Mixed Bed Resin

During the EDI process, the H+ and OH- ions generated by water dissociation continuously regenerate the resin filling the desalination chamber. This self-regeneration is a key factor in the continuous and high-quality water output of EDI water purification equipment. Therefore, if an electroregenerator with a structure similar to an EDI water purification device is manufactured, but whose desalination chamber is not filled with mixed bed resin, then by feeding the exhausted mixed bed resin into it and passing electricity and pure water through it, and running the electroregenerator for a period of time, the exhausted mixed bed resin will inevitably be completely regenerated.

In the regeneration chamber of this electroregenerator, the H+ and OH- ions generated by water dissociation continuously electroregenerate the exhausted mixed bed resin. The salt ions displaced from the resin are continuously migrated to the concentrate chamber and discharged under the influence of the electric field. The exhausted mixed bed anion and cation resins change from basic type to H+ and OH- type resins, completing the regeneration process. Because the exhausted resin does not flow, this method is called static external electroregeneration. Correspondingly, as long as the exhausted mixed-bed resin is continuously fed into the external electro-regenerator, regenerated mixed-bed resin will slowly flow out, thus achieving dynamic external electro-regeneration of the mixed-bed resin. Its working principle is illustrated in Figure 1.

External electro-regeneration of mixed-bed resin utilizes water as a regenerator under the action of a DC electric field, replacing acids and alkalis to regenerate the exhausted mixed-bed resin. Regeneration eliminates the need for complex steps such as separation, regeneration, mixing, and cleaning. Only the exhausted mixed-bed resin is hydraulically transported to the external electro-regenerator for regeneration. It does not require acid or alkali chemicals, is environmentally friendly, consumes only a small amount of electricity, is convenient to use, and is inexpensive, fundamentally changing the traditional ion exchange process.