VITRIFICATION OF INEEL SODIUM BEARING WASTE SURROGATE IN THE SIA RADON COLD CRUCIBLE INDUCTION MELTER

Results of the INEEL sodium-based waste surrogate vitrification test are described. The test was performed at the Radon bench-scale plant equipped with the cold crucible 216 mm in inside diameter. The feasibility of the process has been demonstrated. Some disadvantages were identified such as relatively low glass productivity (~1 kg/h) and high heat expenses (up to ~50 kW×h/kg of glass) but they were believed to be attributed to the introduction of boron flux in the form of boric acid which has high volatility. This reduces the boron content in the glass and increased the glass melting temperature. The cold crucible demonstrated high resistance to molten glass corrosion even at elevated process temperatures (1350-1370 oC) caused by the boron deficiency. The glasses produced were found to be quite homogeneous with minor inclusions of unreacted raw minerals.