The NET Predesign Phase and the ITER Conceptual Design Activity resulted in documented conceptual designs. Assessment of these reports led to the quantification of a reasonable range of values for the tritium inventories of the following systems or plant areas: fuelling, plasma vacuum pumping, fuel purification, blanket tritium recovery, fuel cycle auxiliaries (including isotopic separation system), first wall and divertor, dust produced inside the plasma chamber, blanket, and coolant water of first wall, divertor and blanket. For realistic dose calculations source terms are derived from inventory estimates. Release limitation by process design features and confinement strategy following specific accident scenarios have been considered. The potential to reduce source terms by design improvements and alternative confinement strategies are evaluated.

This paper presents a summary of the results of a detailed design study performed for the Fuel Processing Loop of the Next European Torus (NET). The design is based on the concept of adsorption of impurities on molecular sieve at liquid nitrogen temperature, followed by catalytic oxidation of the regenerated impurities to water, and subsequent reduction of the water by electrolysis. The design study has shown that the process can be engineered using, mostly, available components, and can be designed to be safe. Special design features to make the process passively safe are described. The results of a preliminary safety analysis are summarized. Tritium inventories in the various sections of the process loops are shown. A cost estimate for the overall process system is also presented.

This paper presents integrated hydrogen Isotope Separation System (ISS) designs for ITER based on requirements for plasma exhaust processing, neutral beam injection deuterium cleanup, pellet injector propellant detritiation, waste water detritiation, and breeding blanket detritiation. Specific ISS designs are developed for a machine with an aqueous lithium salt blanket (ALSB) and a machine with a solid ceramic breeding blanket (SBB). The differences in the ISS designs arising from the different blanket concepts are highlighted. It is found that the ISS designs for the two blanket concepts considered are very similar with the only major difference being the requirement for an additional large water distillation column for ALSB water detritiation.

To make a valid contribution to European Fusion objectives, the NET (Next European Torus) must have reactor-like size and operating conditions. This paper proposes for NET; a full size integrated tritium system concept in sufficient detail to permit identification of critical development issues and to serve as a basis for relevant safety and reliability analysis. The proposed options were selected based on the following criteria: (a) minimum risk due to accidents, (b) minimum environmental impact in normal operation, (c) ability to handle a wide range of operating parameters, (d) simplicity and maintainability, (e) required technology development, (f) efficience and cost, (g) relevance to commercial energy production.

An overview is given of the tritium technology activities carried out in the European national laboratories associated with the European Fusion Programme and in the European Joint Research Center. The relationship of these activities to the Next European Torus (NET) design priorities is discussed, and the current status of the research is summarised. Future developments, required for NET, which will be addressed in the definition of the next 5-year programme are also presented.