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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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Fusion Science and Technology
August 2024
Latest News
Nuclear new build procurement considerations
It may seem counterintuitive, but the best time to enhance the ability to support operations and maintenance for a new plant is before construction starts. This is one of many lessons learned by the currently operating nuclear fleet. As construction and startup of many nuclear facilities was completed, it quickly became evident that the ability to efficiently support operations and maintenance was limited. Most of the information necessary to establish and manage procurement of spare and replacement items, maintenance, and configuration of the facilities was unavailable and had to be gathered on a case-by-case, “on-demand” basis. Absence of necessary information and the associated challenges resulted in the need for staff augmentation and multiyear-long projects to develop equipment bills of material and maintenance programs and to perform technical evaluations for the huge quantities of spare and replacement items being requested.
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.