TRS435_web

Ingestion radiotoxicity (Sv/t spent fuel)
10 8
10 7
10 6
10 5
10 4
10 9 1500 a (Partial Pu 99.5% Am + Cm 90%)
270 a
Total
Actinides
Fission products
Ref. 7.83 t U in equilibrium
With P&T
130 000 a
10 3
500 a (Full Pu 99.5% Am + Cm 99%)
10 2
1000 a (Full Pu 99.5% Am + Cm 95%)
10 1 10 2 10 3 10 4 10 5 10 6
Time (a)
FIG. 1. Ingestion radiotoxicity of 1 t of spent nuclear fuel.
99% for americium and curium). The cross-over point is 500 years. If the
curium is left in the waste, this time is extended to 1000 years.
(c) Full multiple recycling of plutonium as well as americium and curium,
with less overall efficiency of P&T processes (99.5% for plutonium and
95% for americium and curium). The cross-over point is 1000 years.
(d) Partial multiple recycling: multiple recycling of the plutonium (99.5%
P&T efficiency) and one single recycling of the americium and curium. In
this case the americium and curium are transmuted in targets in a fast
reactor (FR), with a 90% P&T overall efficiency foreseen. Thus the crossover
point is around 1500 years. In this strategy we can also consider
leaving the curium in the waste; in this event 3000 years is required.
Based on these results, it can be concluded that P&T can help to reduce
the time during which nuclear waste should be isolated from the biosphere
from 130 000 years to between 500 and 1500 years. The fission products radiotoxicity
curve gives the theoretical limit to the total radiotoxicity reduction in
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