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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
D. C. Hunt, Robert E. Rothe
Nuclear Science and Engineering | Volume 53 | Number 1 | January 1974 | Pages 79-92
Technical Paper | doi.org/10.13182/NSE74-A23331
Articles are hosted by Taylor and Francis Online.
In evaluating fissile-material recovery operations involving metal salvage immersed in a reagent, a criticality safety engineer must be able to identify systems of minimum critical mass. Further, he must know the effect on the reproduction factor caused by changes in process variables such as container size or the fissile concentration of the reagent. This paper reports no new experimental results but studies the criticality aspects of fissile-metal immersion by analyzing the most applicable of the existing measurements. The results are expressed in terms of the critical mass of the metal region (excluding the mass of fissile material in solution) as a function of the fissile concentration and dimensions of the liquid cylinder., The analysis indicates that the critical mass of practical combinations of uranium metal and uranium solution always exceeds that of an 18.7-g/cm3, 93.2% 235U-enriched uranium sphere centered in a 300-g/liter metal-water mixture. The corresponding conservative approximation for plutonium systems holds for a 19.7-g/cm3, 95% 239Pu sphere in a 200-g/liter metal-water mixture. The upper limit of applicability of these results is 500 g/liter for both plutonium and uranium systems. The calculational techniques described in this paper underestimate critical masses of uranium by ∼5%; the calculated masses of plutonium are sufficiently overestimated to be conservative in practical applications.