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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
M.TÄSchner, B. Wiener, C. Bunnenberg
Fusion Science and Technology | Volume 14 | Number 2 | September 1988 | Pages 1264-1269
Tritium Release Experiment | doi.org/10.13182/FST88-A25314
Articles are hosted by Taylor and Francis Online.
During two experimental field releases of tritiated hydrogen, performed in France and Canada, a series of measurements was carried out to trace the pathways of tritium in the environment. Information on plume dispersion, HT deposition and conversion into HTO in contact with soil was obtained from analyses of air and soil samples at different positions within the dispersion sector. It was found that HT dispersion can be properly described by the Gaussian plume model, when in the case of the extremely short release the small dispersion parameters of stable weather conditions are used, although the situation was unstable according to Pasquill's classification. HT deposition velocities evaluated from undisturbed and preconditioned field soils confirmed the laboratory findings that the combined process of deposition and biochemical conversion is correlated to the superposition of two countercurrent functions of the free pore volume: HT diffusion in soil on one hand and microbial action on the other hand.
