Affiliations 

  • 1 Malaysian Nuclear Agency
MyJurnal

Abstract

Feasibility studies on the vitrification of spent ion exchange resins combined with glass cullet powder have been conducted using a High Temperature Test Furnace. Bottle glass cullet powder was used as matrix material to convert the ash of the spent resins into a glass. Vitrificat ion of spent ion exchange resins presents a reasonable disposal alternative, because of its inherent organic destruction capabilities, the volume reduction levels obtainable, and the durable product that it yields. In this study, the spent ion exchange resin from the PUSPATI TRIGA reactor of Nuclear Malaysia was combusted in a lab scale combustor and the resulting ash was vitrified together with glass cullet powder in a high temperature furnace to produce a stable spent resin ash embedded in glass. The factors affecting this immobilized waste, such as thermal stability, radiological stability and leachability have all been investigated. However, the outcome of these tests, which include the radionuclide activity concentration in the slag, the optimum conditioning temperature - in relation with volume reduction during vitrification - and the volume mixing ratio of matrix material were reported. It was found that the radionuclides present in spent resins were 54 Mn, 60 Co and 152Eu. The elementary chemical composition (carbon, hydrogen, nitrogen and sulphur) of spent resins was 27.6% C, 5.68% H, 2.04% N and 4.20% S, respectively. The maximum calorific value of spent resins was 1735 kJ/kg. The average activity concentrations of 54 Mn and 60Co in ash at 200oC were 9,411 ± 243 Bq/Kg and 12,637± 201 Bq/Kg. flue gases containing CO2, CO, SO2 and NO started to be emitted above 200oC. The optimum conditioning temperature was also the highest tested, i.e. 900oC in 45 minutes, and the best mixing ratio ash to matrix material was also the highest, ie 1:9. Finally, the leaching analysis of slag at 900oC in 45 minutes showed that the leaching activity of 60Co was below 0.5 Bq/mL.