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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Fusion Science and Technology
Latest News
Take steps on SNF and HLW disposal
Matt Bowen
With a new administration and Congress, it is time once again to ponder what will happen—if anything—on U.S. spent nuclear fuel and high-level waste management policy over the next few years. One element of the forthcoming discussion seems clear: The executive and legislative branches are eager to talk about recycling commercial SNF. Whatever the merits of doing so, it does not obviate the need for one or more facilities for disposal of remaining long-lived radionuclides. For that reason, making progress on U.S. disposal capabilities remains urgent, lest the associated radionuclide inventories simply be left for future generations to deal with.
In March, Rick Perry, who was secretary of energy during President Trump’s first administration, observed that during his tenure at the Department of Energy it became clear to him that any plan to move SNF “required some practical consent of the receiving state and local community.”1
Jason Wilson, James Becnel, David Demange, Bernice Rogers
Fusion Science and Technology | Volume 75 | Number 8 | November 2019 | Pages 802-809
Technical Paper | doi.org/10.1080/15361055.2019.1629249
Articles are hosted by Taylor and Francis Online.
The tokamak exhaust processing (TEP) system performs chemical separations on ITER fuel cycle process streams. TEP recovers hydrogen isotopes (Q2) from impurities such as argon, nitrogen, tritiated water (Q2O), tritiated ammonia (NQ3), and tritiated hydrocarbons such as methane (CQ4). TEP sends the hydrogen isotopes for subsequent processing to the isotope separation system or the storage and delivery system. At the same time, an impurity gas stream of extremely low tritium content (less than 8.88 TBq of tritium per day) is produced and sent to the detritiation system (DS). To accomplish the separation, the major hydrogen processing subsystems within TEP are hydrogen-like processing (HLP) and air-like processing/water-like processing (ALP/WLP). (Hydrogen-like gases are Q2, He, and Ne; air-like gases are Ar, O2, N2, O2, and CQ4; and water-like gases are Q2O and NQ3). The main processing equipment used for the HLP is a series of palladium-silver permeators (PMs) with ALP/WLP using a series of Palladium Membrane Reactors (PMRs). Aspen Dynamics is the primary tool for verifying system performance of the TEP design. Aspen Dynamics is a commercial, equation-based simulation package for chemical processing. The software enables the user to develop a process model from predefined unit-operation models or construct its own unique unit-operations model. Verification of the TEP simulation model to experimental data was achieved during the TEP conceptual design. The designs for the TEP HLP and ALP/WLP subsystems are examined for the updated gas inputs in terms of compositions and flow rates. The TEP simulation is used to predict tritium output of the TEP processing subsystems This paper describes how the Aspen model of the equipment was improved and used to size the equipment (PMs and PMRs) to process the various gas streams and maintain the discharge to DS to below the limit.
