COMPLETE DOCUMENT (1862 kb) - OECD Nuclear Energy Agency

Table II.9 Irradiation of americium targets in FR
CASE 1 2 3
Content (%) 100 40 20
Matrix - Al 2
O 3
Al 2
O 3
Numbers/positions 72 in blanket 72 in blanket 72 in blanket
Mass of americium (kg) 15 673 3 523 1 470
Residence time (EFPD) → 200 dpa NRT 1 500 4 500 5 100
Am depletion consumption rate (%) 20 63 81
Fission rate (%) 6.6 22 38
Am specific consumption (kg/TWhe) 58 14 6.6
Mean target power (MW) 15 2.2 1.2
Mean burn-up (GWd/HMt) 93 80 62
Initial isotopic vector of Am: 241 Am = 63.6%, 242 Am = 0.2%, 243 Am = 36.2%
This concerns an FBR 1400 MWe with two enrichment zones (17.52 and 23.87%). Regardless of the
irradiation time considered, the table does not take account of any intermediate cooling time corresponding
to shutdowns for core refuelling.
2.3.3.2 Minor actinides transmutation in metal-fuelled fast reactor
Studies have been made on minor actinides homogeneously distributed in U-Pu-10% Zr metal
fuel. In any of the technologies currently proposed for pyrochemical reprocessing, the recovered minor
actinides are to some extent accompanied by rare earth fission products. According to the current
pyrochemical reprocessing target value, a DF of 20 is assumed for the process. With this
decontamination factor, the weights of rare earth fission products and minor actinides will be nearly
equal.
In a metal fuel FBR, the minor actinides are homogeneously loaded in core.
There are two modes of fuel recycling [83-85], the self-recycle mode and that with additional
actinides, with respective mass flow pattern as follows:
• in the self-recycle mode, the minor actinides recovered from the spent core fuel in each
FBR are recycled without addition. Consumed plutonium is replaced from LWRs;
• in the minor actinide-enriched mode, the plutonium and minor actinides recovered from the
spent core fuel of each FBR are recycled. Consumed plutonium and minor actinides are
both made up from LWRs. In the particular example, pyrochemical reprocessing was
assumed.
161