As temporary storage facilities for spent nuclear fuel (SNF) are becoming saturated, there is a growing interest in finding solutions for treating SNF, which is recognized as an urgent task. Although direct disposal is a common method for handling SNF, it results in the entire fuel assembly being classified as high-level waste, which increases the burden of disposal. Therefore, it is necessary to develop SNF treatment technologies that can minimize the disposal burden while improving long-term storage safety, and this requires continuous efforts from a national policy perspective. In this context, this study focused on reducing the volume of high-level waste from light water reactor fuel by separating uranium, which represents the majority of SNF. We confirmed the chlorination characteristics of uranium (U), rare earth (RE), and strontium (Sr) oxides with ammonium chloride (NH4Cl) in previous study. Therefore, we prepared U-RE-SrOx simulated fuel by pelletizing each elements which was sintered at high temperature. The sintered fuel was again powdered by heating under air environment. The powdered fuel was reacted with NH4Cl to selectively chlorinate the RE and Sr elements for the separation. We will share and discuss the detailed results of our study.

This study is to perform experiment of concrete according to addition of blast furnace slag powder and sulfur activator dosages. Blast furnace slag powder used at 30, 50, 80% replacement by weight of cement, and liquid sulfur additives was chosen as the alkaline activator. As a result, it should be noted that the sulfur alkali-activators can not only solve the disadvantage of blast furnace slag concrete but also offer the chloride resistance of alkali-activated blast furnace slag concrete to blast furnace slag concrete.

The present study concerns the properties of cement-free concrete using binding capacity of cement paste. The cement-free was casted with alkali-activators(KOH, NaOH, and CaOH2) by weight of binder. The properties of cement-free concrete was studied compare to that of OPC. It was found that an increase in the chloride concentration resulted in a decrease the binding capacity of OPC.