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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Report: New York state adding 1 GW of nuclear to fleet
New York Gov. Kathy Hochul has instructed the state’s public electric utility to add at least 1 gigawatt of new nuclear by building a large-scale nuclear plant or a collection of smaller modular reactors, according to the Wall Street Journal.
Mélany Gouëllo, Jouni Hokkinen, Teemu Kärkelä (VTT Technical Research Centre of Finland)
Proceedings | 2018 International Congress on Advances in Nuclear Power Plants (ICAPP 2018) | Charlotte, NC, April 8-11, 2018 | Pages 293-301
(LWR), radioactive iodine may be released into the environment, impacting significantly to the source term. Determination of the amount released, and of the physical state of iodine (gaseous form or solid aerosol form), is thus a major issue, regarding the improvement of the accident management and mitigation measures The experimental EXSI-PC facility has been specifically designed and built to investigate the behaviour of iodine containing fission product deposits on primary circuit surfaces during a severe nuclear accident. Studies were conducted with two mixtures of caesium iodide and molybdenum oxide (Mo/Cs=1.6 and Mo/Cs=5) in order to assess the possible chemical reactions and the effect on the transport of chemical species through the primary circuit. In addition, two carrier gas compositions (Ar/H2O versus Ar/Air) were studied to highlight the effect of oxygen partial pressure.
In this work, the influence of molybdenum presence on the caesium iodide behaviour under two atmospheres: Ar/H2O and Ar/Air (86.7/13.3 vol.%) was studied. The release of gaseous iodine was higher when the oxygen partial pressure was higher (i.e. for Ar/Air atmosphere). In addition, the results showed that an initial Mo/Cs molar ratio of 1.6 produced about 1.5 times higher amount of gaseous iodine than a ratio of 5. The formation of caesium molybdates was identified in the crucible after the experiments, confirming that the reaction between caesium and molybdenum is the reason for the observed formation of gaseous iodine. The experimental results are mostly in accordance with the equilibrium calculations performed with FactSage.
