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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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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High-temperature plumbing and advanced reactors
The use of nuclear fission power and its role in impacting climate change is hotly debated. Fission advocates argue that short-term solutions would involve the rapid deployment of Gen III+ nuclear reactors, like Vogtle-3 and -4, while long-term climate change impact would rely on the creation and implementation of Gen IV reactors, “inherently safe” reactors that use passive laws of physics and chemistry rather than active controls such as valves and pumps to operate safely. While Gen IV reactors vary in many ways, one thing unites nearly all of them: the use of exotic, high-temperature coolants. These fluids, like molten salts and liquid metals, can enable reactor engineers to design much safer nuclear reactors—ultimately because the boiling point of each fluid is extremely high. Fluids that remain liquid over large temperature ranges can provide good heat transfer through many demanding conditions, all with minimal pressurization. Although the most apparent use for these fluids is advanced fission power, they have the potential to be applied to other power generation sources such as fusion, thermal storage, solar, or high-temperature process heat.1–3
J. Wang, H. Yeom, P. Humrickhouse, K. Sridharan, M. Corradini
Nuclear Technology | Volume 206 | Number 3 | March 2020 | Pages 467-477
Technical Paper | doi.org/10.1080/00295450.2019.1649566
Articles are hosted by Taylor and Francis Online.
Since the accident at Fukushima, one major goal of reactor safety research has been the development of accident tolerant technologies that can mitigate or delay fuel degradation during a beyond-design-basis accident. One major effort has been focused on the development of coatings for light water reactor fuel cladding. Chromium-coated zirconium-alloy clad is one of the leading options. In this work, the MELCOR systems code (version 1.8.6 User-Defined Generalized Coating) is used to evaluate the performance of Cr-coated Zr-alloy clad as compared to Zr-alloy clad and APMT FeCrAl-coated Zr-alloy clad for a pressurized water reactor (i.e., Surry) for a station blackout (SBO) accident scenario. Our focus is primarily on the accident progression behavior depending on oxidation kinetics and the assumed failure criterion for the coated cladding material. Our simulation and comparison indicate that the presence of the coating material can significantly reduce the initial rate of hydrogen generation and delay the time when hydrogen generation becomes significant. This decrease in the rate of oxidation and delay in timing can provide additional coping time for compensatory operator actions. We also note that the effect of extended auxiliary feedwater system operation (long-term SBO) can increase this additional coping time in combination with Cr-coated Zr-alloy, but it is limited by other primary system failures (e.g., hot-leg creep rupture) that will occur driven by core decay heat and independent of coated cladding effects. Finally, we observe that while the initial suppression of hydrogen generation for Cr-coated Zr-alloy clad compared to Zr-alloy is notable, the overall amount of hydrogen produced is similar since hydrogen can also be produced through competing oxidation of stainless steel components during the accident progression. Our future work is focused on the uncertainty analysis of the oxidation rate data, coating failure criteria, and severe accident modeling limitations in order to better quantify accident tolerant fuel clad benefits.
