Uncertainties in modeling of consequences of tritium release from fusion reactors. Plasma Fusion Center No. PFC/TR-79-5

Safety aspects of fusion

“…Fission fuel reprocessing is not commercially practised currently in the USA. European experience for the period [1974][1975][1976] indicates that tritium release to the atmosphere from a reprocessing plant can vary between (3.7 and 167) X 10 12 Bq-(GW(e)a)" than those from Heavy Water Reactors (HWRs), mostly operating in Canada. The expected fusion plant releases are also higher than the projected releases from High Temperature Gas Reactors (HTGRs) and Liquid Metal Fast Breeder Reactors (LMFBRs).…”

“…Under accident conditions, the total tritium inventory may not be released. It has been suggested that tritium in the fuel circulation system and the coolant areas is more vulnerable to accidental release than the tritium in the blanket and storage areas [ 10,12]. However, the probability of releases will naturally depend on the details of each design.…”

“…Piet et al [21 ] pointed out that the steady-state nature of the BHP, the segregated pathways of inhalation and ingestion, and the omission of the sky-shine effects all contribute to rendering the BHP an inaccurate measure of the relative radiotoxicity of the activation products. For accidental releases, a dynamic code like FUSECRAC [22] may be a better tool to assess the Major, elemental constituents of the alloys considered for structural materials are as follows: SS 316:64.4% Fe, 16.5% Cr, 13.9% Ni, 2.8% Mo, 1.5% Mn. PCA: 64.9% Fe, 14.0% Cr, 16.0% Ni, 2.0% Mo, 2.0% Mn.…”

“…Eliminating the multiplier, Piet et al [12] found the time to reach melting in the first wall for STARFIRElike conditions to be about five hours. They used a two-dimensional approach to study the effect of coolant and structural materials on the time-to-damage (defined as 300°C temperature rise) and time-to-melt for the first wall (without the multiplier).…”

“…They a Results of analysis in Ref. [12], where damage was defined as a 300°C temperature rise at the maximum temperature position. b Times greater than 24 h were estimated from the temperature rise rate at the end of the first day.…”