Most Condensate Polishing systems are based on ion exchange (IX) technology. Ion exchange is a reversible interchange of ions between a resin (ion exchange material) and a liquid in which there is no permanent change in the structure of the resin. An ion is an atom or group of atoms with an electric charge. Positive-charged ions are called Cations and are usually metals. Negative-charged ions are called Anions and are usually non-metals.
The impurity ions (positive and/or negative-charged) are taken up by the resin, which must be periodically regenerated to restore it to the original ionic form and depending on the application, there are two types of regeneration method, namely internal and external.
Condensate polishing plants are used for the purification of condensate in a steam cycle in coal fired and natural gas cogeneration plants that are using steam to drive the turbines that run the electric generators. When steam is passed through a series of turbines, expending most of its energy and condensed by heat exchanger system the condensate is treated by condensate polishing system then returned to the boiler where it is converted back into steam.
Condensate polishing system is a unique application of ion exchange resin that removes all soluble impurities created and protects the high-pressure boiler. The condensate polishing system needs to be regenerated from time to time to ensure the ion exchange resins are able to continue to capture soluble impurities and depending on the application, there are two types of regeneration method, namely internal and external. Internal regeneration is referred to when regenerate the resins takes place within the vessel and external regeneration, which is more complicated, is referred to when regeneration takes place outside of vessel used for purification where the resin is transferred to a regeneration vessel, regenerated and then returned to the operating vessel.
