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production of "denaturable"
operating on conventional and denatured fuel cycles are discussed in Chapter 4 and
summarized in Table 7.1-1, where the Light-Water Reactor (LWR) is represented by the
7-8
3%. The plutonium production rates for various reactors
pressurized-water reactor (PWR); the SSCR (Spectral-Shift-Control led Reactor) is a
modified PWR; the heavy-water reactor (HWR) is assumed to be a slightly enriched CANDU;
the High-Temperature Gas-Cooled Reactor (HTGR) is taken to be the Fort St. Vrain plant;
and the High-Temperature Reactor (HTR) of the Pebble-Bed Reactor (PBR) type is represented
by the West German design. Plutonium discharge data for Fast Breeder Reactors (FBRs)
represented by the Liquid-Metal Fast Breeder Reactor (LMFBR) are included for comparison.
It is quite clear from Table 7.1-1 that the denatured fuel cycle for the HWR gives
the greatest reduction in plutonium production between the regular and denatured cycles.
The HTGR has about the same absolute plutonium production for the denatured fuel cycle as
the HWR and in both cases the plutonium amounts are rather small. The HTR-PBR is best in
absolute minimum plutonium production, yielding only 14 kg/GWe-yr and even less in a highly
optimized design.
Table 7.1-1. Fissile Plutonium Discharge for Various
Reactor and Fuel Cycle Combinations
(Capacity Factor = 0.75)
Fissile Pu Discharge (kg/GWe-yr)
LEU Cycle Pu/U Cycle Denatured Cycle
LWR 7 74 858' 63
SSCR 196 - 72
HWR (CANDU)
HTGR
183b
72 -
32
36
HTR-PBR 63 14
.................................
LMFBR - 991 347
;Plutonium burner.
Slightly enriched CANDU.
For the LWR, SSCR and HWR the percentage of the discharge plutonium that Is fissile
plutonium is approximately the same for the denatured cycle as for the LEU cycle. For
the HTGR and PBR, the fissile plutonium percentage is only %39% for the denatured cycle
(compared to 56% for the LEU cycle). Further, the discharge plutonium from the HTGR and PBR,
and also from the HWR, is more diluted with other heavy material by a factor of three to
four than that from the LWR or SSCR. Thus, more material must be processed in the HTGR,
HTR, and HWR to obtain a given amount of plutonium, which provides an additional prolifera-
tion restraint associated with spent fuel discharged from these reactors. However, the
on-line refueling feature of the CANDU, and also of the PBR, may be a disadvantage from a
proliferation viewpoint since low-burnup fuel could be removed and weapons-grade plutonium
extracted from it. On the other hand, premature discharge of low-burnup fuel from the
reactors would incur economic penalties.
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