Management of Low and Intermediate Level Radioactive Wastes by Incorporation into Water Extended Polyesters

Abstract

Two water extended polyester (WEP) resins were prepared and used as incorporation media for simulated spent ion exchange resin used at the Inshas Reactor (Egypt). The suitability of the final waste forms to fulfil the re quirements needed for the final disposal has been tested under different ex perimental conditions. Factors affecting the mechanical stability of the end products such as damp ion exchange resin/polymer ratio, styrene content, type and concentration of initiator were investigated. Radiation stability of polymer waste forms incorporating inactive resin was studied. The samples showed a significant increase in compressive strength values with an increase in irradia tion dose, until a maximum is reached at a dose rate of 2.5 x 108 rads. At higher irradiation doses the values decreased, but they were still higher than those of unirradiated ones. The resistance of WEP resins as well as their final waste forms to most chemical environments was excellent. Oxygen index values illustrated the flame retardancy of WEP waste forms. Leaching experi ments on incorporated blocks of active resin labelled with Cs-137 and Co-60 showed that improved leach resistance was obtained by using deionized water as the leaching solution rather than underground water. The leach factors for Cs-137 were always higher than those for Co-60 using either leachants.