Vaporization of semi-volatile components from Savannah River Plant waste glass
- 1 August 1978
- report
- Published by Office of Scientific and Technical Information (OSTI)
Abstract
Sodium and boric oxides account for approximately 90% of the semi-volatile off-gases that are generated during vitrification of Savannah River Plant waste. The two oxides volatilize as the thermally stable compound sodium metaborate, Na/sub 2/O . B/sub 2/O/sub 3/. The quantity of semi-volatiles increases with increases in (1) the temperature of the melt, (2) the time of vitrification, (3) the surface area of the melt, and (4) the sodium content of the glass-forming mixture. The amounts of semi-volatiles evolved in three hours varied from 1.5 to 9.0 mg per cm/sup 2/ of melt surface. Values between 3.5 to 4.0 mg/cm/sup 2/ were typical for normal melting conditions and compositions. Cesium oxide volatility averaged 0.11 mg/cm/sup 2/ from samples that contained 0.06 wt % Cs/sub 2/O. Volatilities ranged from 0.09 to 0.2 mg/cm/sup 2/. Volatility of Cs/sub 2/O was not significantly suppressed when TiO/sub 2/ was added to the glass melt. Cesium volatility was unaffected when Cs was added to the melt as Cs-loaded zeolite rather than a Cs/sub 2/CO/sub 3/ solution. Over a range of 0.03 to 0.09 wt % Cs/sub 2/O in the melt, volatility of Cs/sub 2/O increased when the Cs content of the melt increased. Lithium volatilitymore » was low and was unaffected by changes in melting conditions or melt composition. Lithium, like sodium, volatilized from borosilicate melts as the metaborate, Li/sub 2/O . B/sub 2/O/sub 3/. (12 tables, 4 figs.) « lessKeywords
This publication has 0 references indexed in Scilit: