ABSTRACT
The performance of the refractory lining in glass melters used for nuclear waste vitrification is critical to the melter reliability for long-term continuous operation. Monofrax® K-3, a high Cr2O3 fused cast refractory material, has been widely used to build the liners of nuclear waste glass melters in the United States. Corrosion behaviour of Monofrax® K-3 refractory has been evaluated based on crucible-scale testing, inspection of the refractory components following scaled melter testing, and inspections of the Defense Waste Processing Facility (DWPF) melter refractory after service. The literature generally consists of empirical models based on short-term testing to describe refractory corrosion dependence on glass composition. Corrosion data from tests with longer testing times, at various temperatures, in the presence of molten salts, and with different redox reactions in the plenum atmosphere exist, may be insufficient to provide accurate refractory service life estimates. Additionally, the corrosion data collected under actual and scaled melter operating conditions are limited. Recommendations to achieve more direct correlation between the laboratory refractory corrosion data predictions and the observed melter service life are discussed to allow for more accurate predictions of the useful life of melter refractory linings.
Acknowledgements
The authors would like to thank Pavel Hrma of AttainX, Support Services Contractor to the Office of River Protection, U.S. Department of Energy and Chris Chapman of Pacific Northwest National Laboratory for criticism and discussion. The authors would also like to thank Renee Russell and Emily Nienhuis of Pacific Northwest National Laboratory and Richard Wyrwas of Savannah River National Laboratory for their help in technical review of this article.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Notes
1 This material was called Carborundum Monofrax® K-3 in some reports in the 1970s–1990s. The Carborundum Company in Falconer, NY used Monofrax as a registered trademark for the product; after years the company has changed its name to Monofrax LLC. The company has been acquired by Saint-Gobain in 2022.