Trial Destruction Test of Spent Cationic Resins in a Molten Salt Oxidation Reactor System

The spent ion-exchange resins have to be disposed of and as such, spent ion-exchange resins are a significant fraction of the combustible organic waste from the nuclear industries. One effective treatment option is incinerating the spent resins to yield ash and gas. However, there are difficulties associated with this approach. One of the criticisms of a high-temperature incinerator is that radioactive and hazardous metals are not retained in the incinerator. In addition, incineration of the cationic exchange resins, which have the sulphurcontaining functional groups of sulfonic acid (-SO3-H+), has revealed significant problems associated with sulfur dioxide (SO2), a primary air pollutant, which must be kept under control. There is therefore the developing need for an alternative destruction process. Molten salt oxidation, or MSO for short, is a promising alternative technology. Molten carbonate filled in a MSO reactor is capable of trapping sulfur during organic destruction. In addition, the relatively low-operation temperature of the MSO reactor reduces the volatility of the radionuclides, compared to the other available high temperature technologies for organics destruction, such as inductively coupled plasma, incineration, plasma arc and microwave heating. Trial destruction tests of spent cationic exchange resins doped with radioactive metal surrogates were performed in this study. Two typical operating parameters, temperature and oxidizing air rate, which significantly affect the organics destruction, were tested to establish the optimum ranges for those parameters