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Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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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.
Bernard Bonin, Dominique Grenéche, Frank Carré, Frédéric Damian, Jean-Yves Doriath
Nuclear Technology | Volume 145 | Number 3 | March 2004 | Pages 266-274
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT04-A3476
Articles are hosted by Taylor and Francis Online.
High-temperature gas-cooled reactors (HTRs) are able to accommodate a wide variety of mixtures of fissile and fertile materials without any significant modification of the core design. This flexibility is due to an uncoupling between the parameters of cooling geometry and the parameters that characterize neutronic optimization (moderation ratio or heavy nuclide concentration and distribution).Among other advantageous features, an HTR core has a better neutron economy than a light water reactor (LWR) because there is much less parasitic capture in the moderator (capture cross section of graphite is 100 times less than the one of water), in internal structures, and in fission products (because of a harder spectrum).Moreover, thanks to the high strength of the coated particles, HTR fuels are able to reach very high burnups, far beyond the possibilities offered by other fuels (except the special case of molten salt reactors).These features make HTRs potentially interesting for closing the nuclear fuel cycle and stabilizing the plutonium inventory.A large number of fuel cycle studies are already available today on three main categories of fuel cycles involving HTRs: (a) high-enriched uranium cycle, based on thorium utilization as a fertile material and high-enriched uranium as a fissile material; (b) low-enriched uranium cycle (LEU), where only LEU is used (from 5 to 15%); (c) plutonium cycle based on the utilization of plutonium only as a fissile material, with (or without) fertile materials.Plutonium consumption at high burnups in HTRs has already been tested with encouraging results under the DRAGON project and at Peach Bottom. To maximize plutonium consumption, recent core studies have also been performed on plutonium HTR cores, with special emphasis on weapon-grade plutonium consumption. We complete the picture by a core study for an HTR burning reactor-grade plutonium. Limits in burnup due to core neutronics are investigated for this type of core.With these limits in mind, we study in some detail the Pu cycle in the special case of a reactor fleet made of a mixture of LWRs and HTRs. It is reasonable to assume that if HTRs are to be deployed on an industrial scale, they will coexist during a long period of time with already existing LWRs. The present paper investigates the symbiotic behavior of LWRs producing plutonium and of HTRs burning it.
