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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Latest News
Constellation seeks subsequent license renewal for Dresden
Constellation Energy has filed with the Nuclear Regulatory Commission for a subsequent license renewal for its Dresden nuclear power plant in Illinois. The extension would allow Dresden to run through 2051.
The filing begins a comprehensive, multiyear review by the NRC. Unit 2 is currently licensed to operate through 2029 and Unit 3 through 2031. The facility’s license was first renewed by the NRC in 2004.
Robert Farkas, Eleodor Nichita
Nuclear Technology | Volume 188 | Number 1 | October 2014 | Pages 34-44
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-128
Articles are hosted by Taylor and Francis Online.
When the coolant is voided in the lattice of a Canada deuterium uranium (CANDU) reactor, the net reactivity change is positive, due primarily to the fact that the coolant and moderator are separated and the coolant volume is much smaller than the moderator volume. The modest loss in moderation occurring when coolant is lost is not sufficient to offset the positive reactivity contributions of increased fast fission rate and reduced epithermal absorption. A way to achieve a negative net reactivity effect on coolant voiding is to increase the importance of moderation in the coolant by decreasing the moderator-to-coolant volume ratio. This work proposes reducing the moderator-to-coolant volume ratio in existing CANDU reactors by packing the moderator with displacers in the shape of hollow spheres in a close-packed pattern. Several materials and shell thickness values are investigated for different fuel enrichments. Calculations are performed using the lattice code DRAGON. Results show that it is possible to reduce the coolant void reactivity in a CANDU lattice with spherical moderator displacers arranged in a hexagonal closed-packed array, albeit at a cost in discharge burnup.