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Conference Spotlight
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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Modernizing I&C for operations and maintenance, one phase at a time
The two reactors at Dominion Energy’s Surry plant are among the oldest in the U.S. nuclear fleet. Yet when the plant celebrated its 50th anniversary in 2023, staff could raise a toast to the future. Surry was one of the first plants to file a subsequent license renewal (SLR) application, and in May 2021, it became official: the plant was licensed to operate for a full 80 years, extending its reactors’ lifespans into 2052 and 2053.
A. M. M. Ali, Hanaa H. Abou-Gabal, Nader M. A. Mohamed, Ayah E. Elshahat
Nuclear Science and Engineering | Volume 195 | Number 5 | May 2021 | Pages 509-519
Technical Paper | doi.org/10.1080/00295639.2020.1839248
Articles are hosted by Taylor and Francis Online.
The neutron spectrum is an essential factor in making possible the increase of 233U isotope breeding from thorium fuel in an accelerator-driven subcritical (ADS) system; therefore, studying the effects of various moderators and coolants on 233U breeding is an important step in ADS performance. This study aims to evaluate the effect of using different moderators and coolants on the ADS system characteristics. Sodium, which was the most common coolant used in ADS reactors, was replaced by light water (LW) and graphite + CO2, separately. In this study, we used uranium nitride as the seed fuel associated with ThO2 as the blanket fuel for all cases. The Monte Carlo transport code MCNPX 2.7.0 was used to calculate neutronic parameters such as effective multiplication factor (Keff), power peaking factor (Pmax/Pav) in the radial direction of the ADS reactor core, actinide isotope evolution during fuel burnup, and power fraction from each fuel type for all cases. The results show that the utilization of graphite as the moderator with CO2 as the coolant allows more 233U production in thorium fuel compared with sodium and LW. On the other hand, LW showed great ability for plutonium and minor actinide transmutation and for energy generation.
