Thermal and Electrical Conductivity of Molten Alumophosphate and Borosilicate Glass Containing Imitators of High-Active Wastes from SNF Processing

Thermal conductivity and electrical conductivity of borosilicate and alumophosphate glass containing imitators of highly active waste (HAW) from the processing of spent nuclear fuel VVER-440 are studied by the methods of coaxial cylinders and impedance spectroscopy from room temperature to 1200°С. For all glass samples, their thermal conductivity increases with temperature growth; however, the thermal conductivity of phosphate glass increases above the glass transition point more significantly to 2.0 W/m K at 1200°С. The thermal conductivity of borosilicate glass containing HAW imitators ranges within 1.40–1.65 W/m K in the temperature range 600–1200°С. The electrical conductivity of alumophosphate and borosilicate glass changes mainly with the concentration of sodium oxide and changes significantly with temperature. The influence of the concentration of the components of HAW imitators on the electrical conductivity of the melts is small in the studied range.