Study on Microwave Curing of Radioactive Waste

Processing of nuclear waste has become an important issue nowadays. A microwave waste disposal method for solid waste mainly containing Ni, Fe element and their oxide produced in the primary loop is investigated in this article. The powder waste, which is treated as absorber of microwave and energy source for curing, was doped in the curing agent that using SiO₂ as a main component. In the experiment, using a household microwave oven (Microwave-frequency: 2.45GHz, Output power: 700W), thermal effects and non-thermal effects make samples heated to a high temperature quickly and then curing. In order to evaluate the effect parameters including different doping ingredient, heating period, pressure were changed. A pressure is applied to make a better curing effect. After curing, the measurement of the density of the cured body was made. The microstructure of the samples was observed with an optical microscope, and the cured body composition was analyzed by XRD and SEM. The results show that samples are sintered quickly with less than 15 minutes and the cured body has a good performance. It’s therefor that microwave technology can be an effective way to dispose microwave absorbing substances such as Fe, Ni-containing powder waste.