Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-28T15:06:17.418Z Has data issue: false hasContentIssue false

Quantitative Assessment of the Instant Release Fraction (IRF) for Fission Gases and Volatile Elements as a Function of Burnup and Time under Geological Disposal Conditions

Published online by Cambridge University Press:  01 February 2011

Cécile Ferry
Affiliation:
CEA Saclay, Nuclear Energy Division, Department of Physics and Chemistry, Bp. 11, F-91191 Gif-sur-Yvette Cedex, France
Patrick Lovera
Affiliation:
CEA Saclay, Nuclear Energy Division, Department of Physics and Chemistry, Bp. 11, F-91191 Gif-sur-Yvette Cedex, France
Christophe Poinssot
Affiliation:
CEA Saclay, Nuclear Energy Division, Department of Physics and Chemistry, Bp. 11, F-91191 Gif-sur-Yvette Cedex, France
Lawrence Johnson
Affiliation:
NAGRA, Wettingen, Switzerland
Get access

Abstract

The Instant Release Fraction at container failure time, IRF(t), is here considered as being the sum of (i) the initial labile fraction, corresponding to the sum of gap and grain boundary inventories of certain radionuclides on exit from the reactor, with a further possible contribution from segregation in the rim region and (ii) the time-dependent fraction of radionuclides accumulating at grain boundaries due to a self-irradiation enhanced diffusion through the grains. The initial labile fraction of radionuclides such as 14C, 36Cl, 79Se, 129I, and 135Cs has been estimated based on leaching experiments, post-irradiation fission gas release measurements and studies of solid-state chemistry of spent fuel, along with estimates of fission product segregation in the rim zone. The contribution of the a self-irradiation enhanced diffusion has also been estimated based on a diffusion coefficient decreasing with time proportionally with the volume α-activity of the spent fuel. Its contribution to the IRF is limited for UO2 fuels. The proposed bounding values of the IRF for fuel with a burnup of 55 GWd/tIHM for 14C, 36Cl, 79Se, 129I, and 135Cs are 11 % at t=0 and close to 15 % at a container failure time of 10,000 y.

Type
Research Article
Copyright
Copyright © Materials Research Society 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Johnson, L.H., Garisto, N.C. and Stroes-Gascoyne, S., Used fuel dissolution studies in Canada, Proc. Waste Management 1985, (eds. Post, R.G., Wacks, M.E.), p. 479).Google Scholar
2. Piron, J.P., Pelletier, M., Petit, T., ICEM'2001 conference, Brugges (Belgium), in pressGoogle Scholar
3. Johnson, L.H., McGinnes, D.F., “Partitioning of radionuclides in Swiss power reactor fuels,” Nagra Technical Report 02–07, (2002).Google Scholar
4. Tait, J.C., Cornett, R.J.J., Chant, L.A., Jirovec, J., McConnell, J. & Wilkin, D.L.. Determination of Cl impurities and 36Cl instant release from used CANDU fuels. Scientific Basis for Nuclear Waste Management XX, (Triay, I. and Gray, W.J., Editors), MRS, Pittsburgh, Pennsylvania (1997).Google Scholar
5. Gray, W. J., Scientific Basis fior Nuclear Waste Management XXII, Materials Research Society, 556, 487494 (1999).Google Scholar
6. Mogensen, M., Pearce, J.H. and Walker, C.T., J. Nucl. Materials, 264, 99112 (1999)Google Scholar
7. Stroes-Gascoyne, S., Tait, J.C., Porth, R.J., McConnell, J.L., & Lincoln, W.J., Waste Management, 4, 385392 (1994).Google Scholar
8. Koo, Y-H., Lee, B.H.., Cheon, J.S., and Sohn, D.S., J. Nucl. Materials, 295, 213230 (2001)Google Scholar
9. Forsyth, R. The SKB spent fuel corrosion programme, SKB Technical Report 97–25. (1997).Google Scholar
10. Matzke, H.J., Rad. Effects, 75, 317325 (1983).Google Scholar
11. Lovera, P., Ferry, C., Poinssot, C., Johnson, L.H., Synthesis report on the relevant diffusion coefficients of fission products and helium in spent nuclear fuel, Spent Fuel Stability under repository conditions European project FIKW-CT-2001–00192 SFS, CEA report (in press)Google Scholar
12. Booth, A.H., AECL Report CRDC-721 (1957).Google Scholar
13. Poinssot, C., Lovera, P., Ferry, C., Gras, J.-M., Scientific Basis for Nuclear Waste Management XXVI, Materials Research Society, (2002) in press.Google Scholar
14. Poinssot, C., Toulhoat, P., Grouiller, J.P., Pavageau, J., Piron, J.P., Pelletier, M., Dehaudt, P., Cappelaere, C., Limon, R., Desgranges, L., Jegou, C., Corbel, C., Maillard, S., Fauré, M.H., Cicariello, J.C., Masson, M. (2001), Synthesis on the spent nuclear fuel long-term evolution, CEA report CEA R 5958, Nov. 01.Google Scholar