Analysis of Fission Gas Release Kinetics by On-Line Mass Spectrometry

The release of fission gases (Xe and Kr) and helium out of nuclear fuel materials in normal operation of a nuclear power reactor can constitute a serious limitation of the fuel lifetime. Moreover, radioactive isotopes of Xe and Kr contribute significantly to the global radiological source term released in the primary coolant circuit in case of accidental situations accompanied by loss of fuel rod integrity. As a consequence, fission gas release investigation is of prime importance for the nuclear fuel cycle economy, and is the driving force for numerous R&D programs. In this domain, for understanding current fuel behavior issues, preparing the development of new fuels (e.g., for Gen IV power systems) and for improving modeling prediction capability, there is a marked need for innovations in the instrumentation field, mainly for: Quantification of very low fission gas concentrations, released from fuel sample and routed in sweeping lines,