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Division Spotlight
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.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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Latest News
Oklo completes end-to-end demonstration of advanced fuel recycling
Oklo Inc. has announced that it has completed the first end-to-end demonstration of its advanced fuel recycling process as part of an ongoing $5 million project in collaboration with Argonne and Idaho National Laboratories. Oklo’s goal: scaling up its fuel recycling capabilities to deploy a commercial-scale recycling facility that would increase advanced reactor fuel supplies and enhance fuel cost effectiveness for its planned sodium fast reactors.
Pavel Hejzlar, Neil E. Todreas, Michael J. Driscoll
Nuclear Technology | Volume 113 | Number 2 | February 1996 | Pages 134-144
Technical Paper | Fission Reactor | doi.org/10.13182/NT96-A35183
Articles are hosted by Taylor and Francis Online.
A reactor concept has been developed that can survive loss-of-coolant accidents (LOCAs) without scram and without replenishing primary coolant inventory while maintaining safe temperature limits on the fuel and pressure tube. The proposed concept is a pressure tube reactor of similar design to Canada deuterium uranium reactors but differing in three key aspects. First, a solid silicon carbide-coated graphite fuel matrix is used in place of fuel pin bundles to enable the dissipation of decay heat from the fuel in the absence of primary coolant. Second, the heavy water coolant in the pressure tubes is replaced by light water, which also serves as the moderator. Finally, the calandria tank, surrounded by a graphite reflector, contains a low-pressure gas instead of heavy water moderator, and this normally voided calandria is connected to a light water heat sink. The cover gas displaces the light water from the calandria during normal operation while during a LOCA or loss of heat sink accident, it allows passive calandria flooding. Calandria flooding also provides redundant and diverse reactor shutdown. The fuel elements can operate under post-critical-heat-flux conditions even at full power without exceeding fuel design limits. The heterogeneous arrangement of the fuel and moderator ensures a negative void coefficient under all circumstances. Although light water is used as both coolant and moderator, the reactor exhibits a high degree of neutron thermalization and a large prompt neutron lifetime, similar to D2O-moderated cores. Moreover, the extremely large neutron migration length results in a strongly coupled core with a flat thermal flux profile and inherent stability against xenon spatial oscillations.