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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
S. A. Hasnain, D. Okrent
Nuclear Science and Engineering | Volume 9 | Number 3 | March 1961 | Pages 314-322
Technical Paper | doi.org/10.13182/NSE61-A25882
Articles are hosted by Taylor and Francis Online.
The performance of some blanket designs is studied using economically optimized cycling based on a simple economics model. For an 800-liter core fast reactor having a 45-cm radial blanket and an average core power of 1-Mw per liter, it appears that the outermost blanket elements make enough plutonium to pay for the cost of their fabrication and processing, unless the core power density falls well below the expected value. A cyclic motion of elements in the inward radial direction has little effect on the economics if optimum cycling is followed. Moving the blanket elements may have engineering advantages however, such as a uniform buildup and burnup, and less variation in power locally with time. A paste blanket with radial inward motion and axial mixing has a similar behavior. Inclusion of moderating material in a fast reactor blanket is not promising for a high-power density reactor using optimum cycling, but it may prove valuable if blanket fluxes get very low or the residence times of the blanket elements are limited.
