Review of FY 2001 Development Work for Vitrification of Sodium Bearing Waste

Abstract

Treatment of sodium-bearing waste (SBW) at the Idaho Nuclear Technology and Engineering Center (INTEC) within the Idaho National Engineering and Environmental Laboratory is mandated by the Settlement Agreement between the Department of Energy and the State of Idaho. This report discusses significant findings from vitrification technology development during 2001 and their impacts on the design basis for SBW vitrification. iv SUMMARYWaste currently stored in tanks at the Idaho Nuclear Technology and Engineering Center (INTEC), located at the Idaho National Engineering and Environmental Laboratory (INEEL), must be processed into waste forms suitable for permanent disposal as part of a Settlement Agreement between the DOE Idaho Operations Office (DOE-ID), the State of Idaho, and the Department of the Navy. In late FY 2000, a roadmap was prepared outlining the technology development required in order to treat this waste, called "sodium-bearing waste" (SBW), using three different technologies. At the direction of DOE-ID, development of vitrification, one of these three technologies, was vigorously pursued in FY-2001. Results from these development activities are contained in twenty-two documents and summarized in tabular form in this report.During FY 2001, a baseline flowsheet for SBW vitrification was defined and a mass balance generated. To manage the assumptions used to generate the process mass balance, the process functional requirements, and all other data that will ultimately be part of the design basis for the SBW vitrification process, a database was created. Much of the knowledge gained in FY 2001 was incorporated into the database and the mass balance, and was published in September, 2001 (Ref. 28). However, results from experiments that were performed late in the year or work that extended into early FY 2002, were not incorporated into the database. Thus a thorough review of the development results from FY 2001 was performed in order to capture in a single source both the progress made in filling data gaps and the impact of these results on the database and hence the basis for the SBW vitrification flowsheet.Significant results were obtained in the areas of feed characterization, feed pretreatment, glass formulation, melter operation, offgas characterization, offgas treatment and secondary waste disposal. Feed characterization data which suggested that the waste may likely contain a higher sulfate content than previously believed together with development of a flowsheet that recycled much of the sulfur in the offgas resulted in development of a glass formulation that tolerates higher sulfur concentration inf the feed, capturing a higher percentage of the feed sulfate in the glass. A maximum waste loading in the glass that forms no salt-layer was found, and the effects of different reductant additives, reductant concentrations, and other process parameters on the formation and growth of a salt layer on the melt were determined. Simulant formulations were developed for both waste from tank WM-180 and...