A study on Leaching Characteristics of Bituminized Solid Form of Radioactive Waste Resin by addition of Poly Ethylene

The bituminized solid form of the radioactive resin waste has the merit that the leaching resistance is superior to that of the other solid forms. It is difficult to apply the precise leaching test to the bituminized solid form due to the lack of its stability. In this study, a modified bituminization technology has been developed, which needs no grinding of resin waste. The Poly Ethylene(PE) was used as the additive. The shape stability increased remarkably with the addition of PE, which acted as a binder in the solid form. The shape of the solid form was maintained entirely during the long-term exposure test when spent PE is added more than 10 wt%. The optimal condition for bituminized radioactive wasted resin was derived from the results of experiment. The bituminized solid form of best quality was made by 40 wt% of resin and 10 wt% of PE. In this case, the density of resin in the solid form was about 1.15 g/. According to the 90-day leaching test of Cs and Co, the leaching characteristic of bituminized solid form was determined as the diffusion. The effective coefficients of diffusion (De) for Cs and Co were 1.621 and 1.186 /day respectively. Leachability Indices were 11.7 and 13.8 each, which were higher than 6 of Nuclear Regulatory Commission(NRC) recommendation.