The plants are designed as weak- and strong acid cation exchangers, weak- and strong basic anion as well as mixed bed exchangers.
The used technologies are co-flow, counter-flow or floating bed exchangers.
The resins used in closed filter vessels carry out the decarbonisation- or desalination process by exchanging ions bound to the resin against ions of the salts dissolved in the water.
Ion Exchangers are insoluble granular substances which have in their molecular structure acidic or basic radicals that can exchange. The positive or negative ions fixed on these radicals are replaced by ions of the same sign in solution in the liquid in contact with them. The ion exchange is complete without deterioration or solubilization nor changing the total number of ions in the liquid before the exchange.The ion exchange substances are used almost exclusively under the name of resins. There are two categories of it: the resins of the gel type and those of the macroporous or loosely cross-linked type. Their basic structure is identical: the macromolecular structure is obtained in both cases by copolymerization. The difference between them lies in their porosity.