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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Fusion Science and Technology
Latest News
ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
Nobuyuki Nakashio, Junya Yamaguchi, Ryusuke Kobayashi, Masabumi Nishikawa
Fusion Science and Technology | Volume 39 | Number 2 | March 2001 | Pages 189-197
Technical Paper | doi.org/10.13182/FST39-189
Articles are hosted by Taylor and Francis Online.
The system effect of tritium arises from the interaction of tritium in the gas phase with water on the surface of piping materials. It has been reported that the system effect can be quantified by applying the serial reactor model to the piping system and that adsorption and isotope exchange reactions play the main roles in the trapping of tritium. The isotope exchange reaction that occurs when the chemical form of tritium in the gas phase is in the molecular form, i.e., HT or T2, has been named isotope exchange reaction 1, and that which occurs when tritium in the gas phase is in water form, i.e., HTO or T2O, has been named isotope exchange reaction 2.The rate of isotope exchange reaction 2 is experimentally quantified, and the rate is observed to be about one-third of the rate of adsorption. The trapping and release behavior of tritium from the piping surface due to isotope exchange reaction 2 is also discussed. It is certified that swamping of water vapor to process gas is effective to release tritium from the surface contaminated with tritium.