The premature degradation of ion exchangers resins used in the water treatment for steam generators and the evaluation of its consequences

The high water purity demanded by the power industry requires removal of practically all the contaminants present in water supplies available to generating plants. For the demineralization system to operate reliably and economically, the ion exchange must be in good condition. The water treatment plants efficiency for the power industry is achieved through a careful selection of the ion exchangers, used in the demineralization process. The types of anion exchangers used for the anionic degrees in the demineralization lines were differentiated through their microstructure specific characteristics (gel, semi-porous, macroporous), their functional groups (primary, secondary, tertiary and quaternary amine) as well as through their matrix (acrylic, styrene - DVB). To select them, one must have a fair knowledge of their performances in what the raw water treatment is concerned, obtained over a period of time covering the seasonal variations of the water source characteristics, as well as of the physic- chemical characteristics of the respective ion exchangers and after well-established operation periods of time. The paper presents the research conducted to identify the risk factors from the Danube river water, that lead to "premature degradation" of the ion exchange resins of type c(from ROHM & HAAS Company) during their exploatation to Nuclear Power Plant CNE-PROD Cernavoda from Romania.