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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Zhiwen Xu, Michael J. Driscoll, Mujid S. Kazimi
Nuclear Science and Engineering | Volume 141 | Number 3 | July 2002 | Pages 175-189
Technical Paper | doi.org/10.13182/NSE02-A2277
Articles are hosted by Taylor and Francis Online.
To provide guidance for future light water reactor core design and fuel management strategies, the effects of the moderator-to-fuel ratio on burnup, core endurance, and waste disposal characteristics have been investigated. The analysis is based on a unit cell model of the standard four-loop Westinghouse pressurized water reactor (PWR) with varied water density, rod diameter, and lattice pitch. Two state-of-the-art computer codes, CASMO-4 and MOCUP (MCNP+ORIGEN), have been used. Considering the entire range of moderation (from fast spectra to overthermalized spectra), the results show that higher reactivity-limited burnup is achievable by either a wetter lattice or a much drier lattice than normal. In particular, epithermal lattices are distinctly inferior performers. Current PWR lattices are about the optimum in terms of highest fuel endurance. However, wetter lattices produce less plutonium with a degraded plutonium isotopic mix with respect to weapons usability. Neptunium-237 content is only mildly affected by the hydrogen-to-heavy-metal ratio. High burnup is significantly beneficial to reducing plutonium production per unit energy and to making its isotopic mix less attractive as a weapon material. In particular, the 238Pu to 239Pu ratio increases approximately as the 2.5 power of burnup for a fixed initial enrichment. Based on this neutronics study, wetter lattices are recommended for future high-burnup applications.