The JET Active Gas Handling System (AGHS) was designed, built and commissio
ned to handle radioactive tritium gas mixtures safely, to supply tritium (T
-2) and deuterium (D-2) to the JET torus, to process the exhaust gases with
the main purpose to enrich and re-use T-2 and D-2, to detritiate tritiated
impurities and to keep discharges below the approved daily release limits.
In addition, the AGHS had to supply the necessary ventilation air streams
during maintenance or repair inside or outside of the AGHS building. During
the first Deuterium-Tritium Experiment (DTE1) at JET in 1997 the AGHS fulf
illed all these tasks in an excellent manner. No unauthorised or unplanned
tritium releases occurred and no operational delays were caused by the AGHS
. In fact, this was the first true demonstration that quantities of tritium
in the tens of grams range can be recycled safely and efficiently in a lar
ge fusion device. At the start of DTE1 20 g of tritium were available on th
e JET site. About 100 g of tritium were supplied from the AGHs to the users
which necessitated the recycling of tritium at least five times. Approxima
tely 220 tritium plasma shots were performed during DTE1. Large amounts of
tritium were temporarily trapped in the torus. This overview presents the p
erformance of the whole AGHS during DTE1 as well as general aspects such as
the preparation for DTE1; the quantities of gases supplied from the AGHS t
o the users and pumped back to the AGHs; tritium accountancy; interlock sys
tems; failure of equipment; and gives detailed information of the gas proce
ssing in each subsystem of the AGHS. As a result of the performance of the
AGHs during DTE1 we can state confidently that the AGHS is ready for furthe
r Deuterium-Tritium Experiments. (C) 1999 JET Joint Undertaking. Published
by Elsevier Science S.A. All rights reserved.