An experimental device to study the revaporisation behaviour of fission product deposits under severe accident conditions

This paper describes the main features of this device, including a series of upgrades on-going or planned to extend the applicable range of FPs and atmosphere conditions. Test results of FPs deposited on the surface of stainless steel rings from the upper vertical line of the Phébus FP tests are presented. Experiments under steam atmosphere showed that revaporisation of 137Cs starts at 540 °C progressing rapidly until near the total depletion of the deposit, resulting in a total revaporisation of ∼92%.