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question could be accomplished via international facilities chartered for just such a pur-
pose.
Such centers (and the institutional arrangements attendant to them) could also serve
as forerunners of the full-scale fuel cycle service/energy center concept considered for the
recycl e-based options.
I
7.5.2. Recycle Options
The inherent limitations of the resource base would require the use of recycled
material to supplement the LEU cycle if the growth of a nuclear-based electrical generation
capacity were to be sustained. Table 7.5-1 compares three recycle options utilizing de-
natured fuel (Cases E-G) with two reference recycle options utilizing the classical Pu/U
cycle (Cases C and D). The two reference cycles differ in that Case D employs FBRs while
Case C does not. The denatured cases differ in that Cases E and F are all-thermal systems
and Case G employs FBRs in addition to thermal reactors. Case E uses only LWRs as dis-
persed reactors while Case F uses both LWRs and advanced converters (HWRs, HTGRs, or SSCRs).
It has been assumed that, given a strong government mandate and financial support,
all the fuel cycles and reactor types that have been considered in this report could be
developed by the time they would be needed - by the year 2000 or later. However, the
Pu/U cycle is much closer to being commercialized than the Th-based cycles, and, as noted
in Chapter 5, the research, development, and demonstration costs for implementing the
denatured 233U fuel cycle in LWRs would be between $0.5 and $2 billion higher than the
costs for implementing the reference Pu/U cycle in LWRs. If the HWR or HTGR were the
reactor of choice, an additional $2 billion would be required for reactor research,
development, and demonstration.
A system in which reactors consuming Pu and producing 233U (transmuters) are
combined with reactors operating on denatured 233U fuel appears to have somewhat better
proliferation-resistant characteristics than a system based solely on the Pu/U cycle.
The "fresh" 233U fuel is denatured with 238U, and thus some of the proliferation-resistant
features of the front end of the LEU cycle would be extended to the recycle mode.
is, both chemical and isotopic separation of the fresh fuel would be necessary to obtain
weapons-usable material. Additionally, the fresh denatured fuel is contaminated with
radioactivity due to the decay daughters of a 232U impurity that is unavoidably produced
along with the
procedure would be severe. By contrast, weapons material could be obtained from Pu/U or
23%/Th fuel through chemical separation alone, although the 23% obtained would also be
radioactive due to the 232U daughters.
less so.)
That
33U, and the associated complications introduced into the isotope separation
(The Pu/U fuel would also be radioactive but much
The spent denatured fuel represents a somewhat lower proliferation risk than the
spent fuel from other options would. The recovery of a given quantity of Pu bred in the
238U denaturant would require the processing of more material than would be necessary in