Safety analysis of the Compact Ignition Tokamak (CIT) release of activated solid material.

摘要

Recent safety studies for the Compact Ignition Tokamak (CIT) have addressed the potential risk associated with the release of activated solid materials from sources such as the vacuum vessel and the TF coils, including insulation, as a result of off-normal events associated with the machine. A number of initiating events have been identified that could lead to mobilization of the activated material and the maximum quantities that could be mobilized have been estimated. These events include: a gas break into the torus releasing tokamak dust, plasma disruptions vaporizing first wall material, graphite combustion volatilizing activated structural material, and magnet arcs volatilizing magnet or torus material. Several operating scenarios, both bounding and realistic, have been investigated to determine a spectrum of isotope concentrations which might be present in the materials. Source terms for the various release scenarios are established using this information. The various release modes are identified along with factors which could reduce the amounts of activated material actually released. From this information, the doses resulting from a spectrum of releases are presented and discussed. A number of factors, identified in the paper, lead to the conclusion that accidental release of activated solids does not present a significant public risk from the operation of CIT. 11 refs., 2 tabs.