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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
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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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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.
B.-G. Brodda, D. Heinen
Nuclear Technology | Volume 34 | Number 3 | August 1977 | Pages 420-427
Technical Paper | Chemical Processing | doi.org/10.13182/NT77-A31807
Articles are hosted by Taylor and Francis Online.
The radiolytic load of the 30 vol% tributylphosphate-n-paraffin extractant to be used in the Jülich Pilot Plant for Thorium Element Reprocessing facility for reprocessing thorium high-temperature reactor (THTR) fuel elements with high burn-up values (85 000 MWd/MT of heavy-metal atoms) was calculated. At a radioactivity level of ∼2000 Ci/ℓ, the effective beta-particle power density of the feed solution ranges up to 15 W · ℓ−1. Most of the energy absorbed by the extractant is due to beta radiation (99%). About 1% originates from gamma radiation; contributions from alpha-particle emitters are negligible. The calculations consider the geometric parameters of the applied mixer-settler and the operational parameters of the flowsheet. The highest exposure expected will be ∼0.2 Wh · ℓ−1 · pass−1 when reprocessing fuel with 85 000 MWd/MT burnup after a cooling time of 100 days. For an easier comparison of the calculated value with other reported values, a coefficient is introduced describing the specific exposure of the extractant in terms of energy absorption per hour of passing through the contactor at a power density of 1 W· ℓ−1 in the feed solution. This coefficient is independent of such individual flowsheet conditions as heavy-metal concentration or power density in the feed solution. Comparison of calculated data with other reported data for THOREX and PUREX reprocessing runs exhibits only about a four-fold specific load of the extractant in case of reprocessing high-burned-up THTR fuel with respect to low-enriched low-burned-up light water reactor fuel. This underproportional increase is due to the specific fission-product spectrum of the investigated THTR fuel arising in the course of its reactor residence time.