First Phase of the Spent Fuel Autoclave Leaching Experiments (SF-ALE) at SCK-CEN

Abstract

Deep geological disposal of high level nuclearwaste, such as spent nuclear fuel is being considered byseveral countries, including Belgium and Germany.Ultimately, such a scenario considers contact betweenunderground water and the fuel due to aging andcorrosion of the materials. The SF-ALE research programcontributes to a better understanding of the release ofradionuclides from the fuel as a function of thesurrounding environment. An improved autoclave setupwas developed, allowing to simultaneously investigate therelease of water-soluble and gaseous components fromthe fuel. Six experiments (three on irradiated UO2 andthree on irradiated MOX fuel samples) have recently beenstarted and will run over 1.5 years, followed by anextension of another 1.5 years. A description of the hotcell equipment, analytical techniques used and themicrostructural characterization of the irradiated fuelsamples will be presented