Key components of the JET Active Gas Handling System — experimental programme and test results

The JET Active Gas Handling System is designed to process mixtures of hydrogen isotopes, helium and impurities during the operation of the JET tokamak with deuterium/tritium plasmas. Elements of crucial importance for plant operation have been built as prototypes and tested. The results show that•- the separation of hydrogen mixtures from impurities in the elements of the cryogenic forevacuum system works to the low ppm levels;•- uranium beds with internal cooling are capable of high take-up rates of hydrogen (100% of capacity in ∼15 minutes);•- uranium and iron beds are capable of tritium recovery from tritiated water, ion beds are regenerable;•- all metal valves, actuators and pressure regulators designed to work in all-metal vacuum double containments meet the design requirements. Furthermore, new methods for the recirculation of hydrogen streams in a cryodistillation system and the detection of isotopic transitions in a preparative gas chromatogtraphy system are described. The present state of the JET AGHS is reported.