ガラス粉末の水熱ホットプレスによる模擬HLWの固定化

抄録

Glass powder was solidified with simulated high-level radioactive waste (20_??_ HLW) by hydrothermal hot-pressing technique. The compressive strength and leach rate of the solid (20_??_ HLW) were measured.
The mixture of glass powder and simulated waste was easily solidified in the presence of water. The solid produced at 280°C for 1 h had the high compressive strength about 200 MPa. The solid showed the highest compressive strength in the case of the porosity was 10_??_ in the solid. The result showed that the pore in the solid defended the extension of stress. The solid produced at 320°C for 2 h showed the lowest leach rate, and XRD of the solid showed the disappearance of α-quartz. Strontium was not detected in the leachant (<0.04 ppm). The solid containing Al(OH)₃ was showed a low leachability of Cs. The result showed the formation of pollusite in hydrothermal reaction.
A canister was proposed for the hydrothermal hot-pressing method. The mixture of glass powder and high-level radioactive waste will be solidified the canister which will be stored.