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Immobilizing low-activity waste (LAW) stored at Hanford site will result in approximately 200 000 m3 of waste glass. It must be demonstrated that this glass can adequately retain radionuclides and prevent contamination of the surrounding environment. A study is being performed to determine the effect of glass composition on its capability to withstand the conditions in the Hanford site burial scenario. To predict the long-term corrosion behavior of waste glass, it is necessary to study the composition and properties of alteration products. The vapor hydration test (VHT) and product consistency test (PCT) were selected as the methods to accelerate the corrosion process and to form alteration products. VHT and PCT was performed on 75 glasses, of which 45 were designed to systematically vary the composition. VHTs were conducted at temperatures ranging from 90?C to 300?C. Alteration rates for most glasses are being determined at 200?C. Selected glasses were tested at different temperatures to determine the effect of temperature on the assemblage of alteration products and the apparent alteration rates. PCTs were performed at a glass surface area to solution volume ratio (S/V) of 2000 m-1 for 7 d and at a S/V of 20 000 m-1 for 10, 100, 1000,more » 5000, and 10000 h all at 90?C.« less |
