Characterization of JT-60U exhaust gas during experimental operation

摘要

Characterization of Tokamak exhaust gas, gas species and their concentrations, is important for the design of the tritium fuel processing system. The exhaust gas from JT-60U during the experimental campaign has been investigated with micro gas chromatography (MGC). Gas species, such as hydrogen isotopes, CH_4, C_2H_2 + C_2H_4, C_2H_6 and CO_2, in the exhaust gas from a plasma discharge could be identified successfully. In this campaign, the total ratio of hydrogen isotopes and impurity species in exhaust gas was estimated to be 39 to 1. From the comparison between both amount of gas species and some plasma parameters, there was a tendency observed indicating that the amount of hydrogen isotopes and carbon compounds increased with maximum electron density. This relation suggests that the amount of hydrogen isotopes and carbon compounds in the exhaust gas is increases with the extension of plasma performance.