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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
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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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Fusion Science and Technology
Latest News
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
Anselmo Cisneros, Nicholas Zweibaum, Christian Di Sanzo, Jeremie Cohen, Ehud Greenspan, Per Peterson, Bernhard Ludwigt
Fusion Science and Technology | Volume 61 | Number 1 | January 2012 | Pages 431-435
Other Concepts and Assessments | Proceedings of the Fifteenth International Conference on Emerging Nuclear Energy Systems | doi.org/10.13182/FST12-A13458
Articles are hosted by Taylor and Francis Online.
The proliferation resistance of the nuclear fuel cycle would be increased if one could eliminate the need for both uranium enrichment and spent fuel reprocessing. Heavy-water and graphite moderated critical reactors can extract energy from natural uranium but offer a very low uranium utilization (low discharge burnup). The objective of the present study is to explore the feasibility of achieving high fuel utilization without resorting to enrichment and reprocessing using spallation neutron source driven subcritical reactors. Three different high burnup once through subcritical nuclear systems are investigated: a fluoride salt cooled high temperature reactor (FHR) with pebble fuel, a helium cooled core with sphere pack fuel based on General Atomics' EM2 reactor concept, and a sodium cooled fast reactor that is loaded with fuel discharged from a high burnup Breed-and-Burn (B&B) fast reactor that is fed with depleted uranium, after removing the gaseous fission products and inserting the voided fuel rods into a new clad (without removing the old one).The pebble fuel design and fuel cycle for the FHR concept was optimized for maximum electric power multiplication using natural thorium fuelled subcritical core. The maximum attainable power multiplication was not high enough to merit future studies.The optimal discharge burnup of the fuel in the EM2 type subcritical core was found to be approximately 30% FIMA and the corresponding power multiplication was found higher than in the FHR but still not high enough for practical applications.Significantly better performance was obtained from the sodium-cooled source-driven core that is fed with metallic U-TRU-Zr fuel discharged at 20% FIMA from a critical B&B fast reactor that underwent recladding. The maximum attainable power multiplication was found to be close to 10 while fissioning an additional 20% of the loaded heavy metal.
