Development of new crud removal ion exchange resin DIAION HPAN10 used in nuclear power plants

The metal corrosion products generated in the water systems of nuclear power plants (crud) should be efficiently removed from the water in order to maintain the safety and reliability of the plants' constituent materials and reduce radiation exposure to workers. Recently, we developed a new highly porous type of anion exchange resin product, 'DIAION HPAN10', which has high crud removal capability. The model crud removal capability of HPAN10 is ten times greater than that of conventional gel types. However, in general, highly porous resins, with highly-developed porous structures, have the low physical strength, and the level of turbid substances and eluate generated by the resin surface is very high. We improved and enhanced the physical strength of HPAN10 and as a result the level of turbid substances and eluate decreased to a practical level. In regards to the application of HPAN10 in nuclear power plants, we believe it is suitable for use with conventional gel type mixed bed resins which are used abundantly in primary water systems. For example, we recommend that HPAN10 is overlaid on the layer of mixed bed rein in a demineralizer, and, consequently, we think it shows high crud removal capability because of its synergetic effect. (author)