Breeding of 242mAm in a Fast Reactor

• Published in: Nuclear technology 2006-02, Vol.153 (2), p.224-233
• Main Authors: Ronen, Y., Aboudy, M., Regev, D.
• Format: Article
• Language: English
• Subjects: Applied sciences; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fission nuclear power plants; Fuels; Installations for energy generation and conversion: thermal and electrical energy; Nuclear fuels; Preparation and processing of nuclear fuels
• ISSN: 0029-5450; 1943-7471
• DOI: 10.13182/NT06-A3702

There is growing interest in the use of 242m Am as a nuclear fuel. Since the thermal absorption cross section of 242m Am is very high (σ a = 8950 b), the best way to obtain 242m Am is by the capture of fast or epithermal neutrons in 241 Am. As a result, we have considered replacing the radial blanket of a fast reactor, which is usually depleted uranium, with 241 AmO 2 . We chose a 714-MW(thermal) MONJU reactor, and we replaced some of the radial blanket and the outer core assemblies with 10 676 kg of 241 AmO 2 fuel. We calculated the reactor core by using the MCNP Monte Carlo code. The total amount of 242m Am becomes stabilized after 16 yr, but the enrichment does not. In our calculation, ~7.2% enrichment is obtained after 18 yr. Obtaining higher enrichments might indicate that 242m Am nuclear fuel can be used without further enrichment in many cases. The results presented in this paper are considered an upper limit scenario. In particular the target 241 Am loading is not likely to be available soon, but 242m Am production from lesser amounts is easily scaled down proportional to the actual mass irradiated.