Lee Hsun Lecture Series

Topic: A MODEL FOR THE CORROSION OF SPENT NUCLEAR FUEL, AND THE RELEASE OF RADIONUCLIDES, INSIDE A FAILED WASTE CONTAINER.

Speaker: David Shoesmith
            Surface Science Western and the Department of Chemistry
            Western University, London, Ontario, N6A 5B7，Canada

Abstract:

The internationally accepted approach for the disposal of spent nuclear fuel is to seal it in a corrosion-resistant metal container and bury it in a stable deep geologic repository. While the prospects for containment are good, it is judicious to investigate the consequences of container failure, when the fuel waste form could be exposed to groundwater. Under these conditions, radiolytic corrosion of the fuel (uranium dioxide (UO₂) containing a range of fission and activation products) could lead to the release of radionuclides to the groundwater, the critical first step in their transport into the environment.
Two corrosion fronts will exist within the failed container; one on the fuel surface driven by radiolytic oxidants, and a second on the carbon steel vessel sustained by water reduction. The coupling of these two corrosion fronts via diffusive transport in the groundwater would then lead to an evolution in redox conditions with time which will control the fuel corrosion rate. Based on an extensive series of electrochemical, corrosion and chemical dissolution studies, a finite-element based model has been developed to determine this evolution in redox conditions and its influence on fuel corrosion/radionuclide release. The key properties of the spent fuel which influence its reactivity will be described and their effect on the fuel corrosion process calculated. An attempt will be made to validate the model based on a wide range of international studies on spent fuels and simulated fuels.

David.W. Shoesmith

Department of Chemistry, Western University
London, Ontario, N6A 5B7
CANADA
Tel. 519-661-2111 (86366)
FAX 519-661-3022
dwshoesm@uwo.ca

David Shoesmith is a Professor in the Department of Chemistry (since 1998) and the Director of Surface Science Western (since 2011). He received his Ph.D. in Electrochemistry from the University of Newcastle-upon-Tyne in 1970 and was a Research Scientist with Atomic Energy of Canada (Whiteshell Laboratories) from 1973 to 1998. He presently holds the Natural Sciences and Engineering Research Council and Nuclear Waste Management Organization (NSERC/NWMO) Industrial Research Chair in Nuclear Fuel Disposal Chemistry (since November, 2000).

He is an elected fellow of the Royal Society of Canada (2016), the National Association of Corrosion Engineers (NACE International) (1996), the Canadian Society for Chemistry (1985) and the Electrochemical Society (2011). He has won awards from the Electrochemical Society (Lash Miller award (1979), Canadian Electrochemistry award(2010), H.H. Uhlig award (2015)), NACE International (Whitney award (2011)), The Chinese Academy of Science (Lee Hsun Lecture award (2015)), the Canadian Institute of Mining and Metallurgy (Cohen award (2001), Atomic Energy of Canada (Discovery award (1994)), and Western University (Distinguished Professorship (2005), Excellence in Graduate Student Mentoring (2010)).

He has published over 300 peer-reviewed papers and conference proceedings, 150 company and commercial reports, given ~ 100 invited lectures and award addresses, and coauthored ~350 conference presentations and posters.

His research is on the electrochemistry and corrosion of materials with a special emphasis on the corrosion of uranium dioxide and nuclear waste container materials under permanent waste disposal conditions. In these areas he has collaborative projects with universities and research organizations in Sweden, South Korea, Spain and Argentina. 

His research is also funded by automobile, chemical processing and oil and gas transmission companies.