skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Results from long-term dissolution tests using oxidized spent fuel

Conference ·
OSTI ID:6421482

Two semi-static dissolution tests using oxidized PWR spent fuel specimens are being conducted under ambient hot cell conditions in Nevada Test Site J-13 well water and unsealed fused silica vessels. The test specimens were oxidized at 250{degree}C in air to bulk oxygen-to-metal (O/M) values of 2.21 and 2.33. Following an initial 191-day test cycle, the specimens were restarted in fresh J-13 water for a second long-term test cycle. Results through the first 40 months of Cycle 2 are compared with results from similar tests at 25{degree}C and 85{degree}C using unoxidized spent fuel specimens. Increased concentrations of U, Am, Cm and NP were measured in 0.4-{mu}m filtered samples from the oxidized fuel tests compared to the unoxidized fuel tested at 25{degree}C; Pu concentrations were not affected by the fuel oxidation state. Most of the Am and Cm, and a portion of the Pu, measured in 0.4-{mu}m filtered samples was removed by 2-nm filtration. Fission product release results were normalized to specimen inventories and reported as fractional release. No attempt was made to normalize the data to surface area. Initial {sup 99}Tc release was greatly increased, and prolonged increases in the fractional release rates of {sup 99}Tc and {sup 129}I occurred as a result of fuel oxidation. Fractional release rates for {sup 137}Cs and {sup 90}Sr from oxidized fuel eventually decreased to levels similar to those observed with unoxidized fuel after equivalent testing times, suggesting that matrix dissolution rates normalized to fuel mass were not increased as a result of oxidation. 6 refs., 3 figs., 2 tabs.

Research Organization:
Pacific Northwest Lab., Richland, WA (USA)
Sponsoring Organization:
DOE/RW
DOE Contract Number:
AC06-76RL01830
OSTI ID:
6421482
Report Number(s):
PNL-SA-18263; CONF-9011116-5; ON: DE91005177
Resource Relation:
Conference: 14. nuclear waste management conference, Boston, MA (USA), 26-29 Nov 1990
Country of Publication:
United States
Language:
English