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Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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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
Anthony W. LaPorta
Nuclear Technology | Volume 205 | Number 10 | October 2019 | Pages 1290-1301
Technical Paper | doi.org/10.1080/00295450.2019.1565471
Articles are hosted by Taylor and Francis Online.
The Transient Reactor Test (TREAT) facility was constructed in 1958 and became operational in 1959. The TREAT reactor is an air-cooled test reactor that can be operated in multiple modes: up to 20 GW for short-duration “burst” pulses (approximately 100 to 200 ms) producing an intense neutron pulse; lower power (megawatt range)–shaped transients intended to simulate fuel heating prior to accident conditions being imposed; or in a low power mode of up to 120 kW for experiment preconditioning or neutron radiography. TREAT operated from 1959 through 1994 when it was put into a standby condition. With the accident at Fukashima-Daiichi that resulted in extensive fuel failure, the U.S. Department of Energy selected TREAT for restart and irradiation of new accident-tolerant fuel designs for U.S. commercial nuclear plants. This paper discusses the basic process that was used to perform the initial criticality following the TREAT extended shutdown operation from 1994 to 2017.
