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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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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August 2024
Latest News
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.
Orrington E. Dwyer, Herbert E. Howe, Edward R. Avrutik
Nuclear Science and Engineering | Volume 12 | Number 1 | January 1962 | Pages 15-22
Technical Paper | doi.org/10.13182/NSE62-A25364
Articles are hosted by Taylor and Francis Online.
The liquid-metal-fuel reactor concept, which has received much attention in recent years, in its commonest version is a thermal breeder and employs as a fuel a dilute solution of U in molten Bi. About 28% of the nonvolatile fission products are less reactive chemically than U. This group, customarily referred to as the FPN group, is further divided into three subgroups according to the proposed methods of removal. The FPN-I's would be removed by oxidizing them to chlorides with fused salts, the FPN-II's by precipitating them directly from the liquid fuel, and the FPN-III's by reaction with Zn to form low-density intermetallic compounds which are insoluble in Bi. The FPN-II's, representing about 90% of the FPN's, would be removed continuously, while the others, because of their low yields or relatively low thermal cross sections, would be allowed to build up in the fuel for several years without causing any particular concern. Eventually, however, they would have to be removed. The FPN-I's would be removed by the same continuous process proposed for removing those nonvolatile fission products which are more reactive than U, while the FPN-III's would be removed in a batch process similar to that currently used in the refining of Bi. The following paper includes information on the rates of build-up of the several important FPN elements in the fuel, steady-state concentrations of the FPN-II elements, reactor poisoning level of the FPN's, and experimental results in support of the proposed methods of removal.