Corrosion Behavior of High Burnup Spent Fuel in Highly Alkaline Solutions

A. Loida, R. Gens, V. Metz, Karel Lemmens, Christelle Cachoir, Thierry Mennecart, B. Kienzler, Karine Ferrand

Research outputpeer-review

Abstract

Contact of highly alkaline solution with spent fuel is considered in the Belgian concept for disposal in the Boom Clay formation. According to the “supercontainer design” the fuel will be encapsulated in carbon steel canisters, surrounded by a concrete overpack. After saturation of the engineered barriers by porewater, interactions with the concrete will result in solutions rich in NaOH, KOH and Ca(OH)2. Using this type of solution at pH 12.5, spent nuclear fuel corrosion experiments were conducted over 378 days. Under anoxic conditions, parallel experiments were performed (a) in the absence of Fe phases and (b) in the presence of solid Fe phases representing container (corrosion) products. Both types of experiments resulted in relatively low matrix dissolution rates, around 10-7 per day, according to the fractional release of Sr. Solution concentrations of actinides are close to or below the detection limit. The observed precipitation of a Ca rich phase onto the surfaces of the corroded fuel samples may be related to the inhibited release of actinides, Sr and other matrix bound radioelements.
Original languageEnglish
Title of host publicationScientific Basis for Nuclear Waste Management XXXIII. Symposium Proceedings. Volume 1193
Place of PublicationWarrendale, PA, United States
Pages597-604
StatePublished - Dec 2009
Event33rd International Symposium "Scientific Basis for Nuclear Waste Management". MRS - V.G. Khlopin Radium Institute, St. Petersburg
Duration: 24 May 200929 May 2009

Publication series

NameMaterials Research Society proceedings
NumberVolume 1193

Conference

Conference33rd International Symposium "Scientific Basis for Nuclear Waste Management". MRS
Country/TerritoryRussian Federation
CitySt. Petersburg
Period2009-05-242009-05-29

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