MA Doping Analysis on Breeding Capability and Protected Plutonium Production of Large FBR

Abstract

Spent fuel from LWR can be seen as long‐live waste if it is not recycled or as a “new fuel” resource if it is recycled into the reactors. Uranium and plutonium have been used for “new fuel” resources from LWR spent fuel as MOX fuel type which is loaded into thermal reactor or fast reactor types. Other actinides from the spent fuel such as neptunium, americium and curium as minor actinide (MA) are considered to be loaded into the reactors for specific purposes, recently. Those purposes such as for increasing protected plutonium production and breeding capability for protected plutonium as well as in the same time those amount of MA can be reduced to a small quantity as a burner or transmutation purpose. Some investigations and scientific approaches are performed in order to increase a material “barrier” in plutonium isotope composition by increasing the even mass number of plutonium isotope such as Pu‐238, Pu‐240 and Pu‐242 as plutonium protected composition. Higher material barrier which related to intrinsic properties of plutonium isotopes with even mass number (Pu‐238, Pu‐240 and Pu‐242), are recognized because of their intense decay heat (DH) and high spontaneous fission neutron (SFN) rates. Those even number mass of plutonium isotope contribute to some criteria of plutonium characterization which will be adopted for present study such as IAEA, Pellaud and Kessler criteria (IAEA, 1972; Pellaud, 2002; and Kessler, 2007). The present paper intends to evaluate the breeding capability as a fuel sustainability index of the reactors and to analyze the composition of protected plutonium production of large power reactor based on the FaCT FBR as reference (Ohki, et al., 2008). Three dimensional FBR core configuration has been adopted which is based on the core optimization calculation of SRAC‐CITATION code as reactor core analysis and JENDL‐3.3 is adopted for nuclear data library. Some MA doping materials are loaded into the blanket regions which can be considered as breeding region for protected plutonium production. Breeding capability of the reactor can be increased effectively by increasing MA doping rate while criticality condition of the reactor is reduced by doping MA. Adopting MA cycle is also effective to increase the isotopic Pu‐238 production in plutonium vector composition for denaturing purpose of plutonium.