Sometimes the demineralised water of an ion exchanger or RO is not of a sufficient quality and an extra treatment is needed. This is called 'polishing'.
Thanks to the mixed-bed-ion exchangers it is possible to obtain a very low conductivity. The mixed-bed technology is an alternative for EDI-technology.
In a mixed-bed ion exchanger the cation- and anion-resins are in the same bottle. This causes a more difficult regeneration because the resins need to be separated prior to regeneration (they have a different mass density). Afterwards it is important that the acid flows over the cation-resins and the base over the anion-resins.
PCA can help you with this technology, both in design and construction of the installation.