ORNL-5388 - the Molten Salt Energy Technologies Web Site

7-24
introduced within the centers to provide an additional means for 233U production, as well
as additional power production. Concurrently, 233U (and unburned 235U) recovered from
MEU(235)/Th or from partial thorium loadings could be utilized in denatured 233U fueled
LWRs introduced at dispersed sites. Later, 233U recovered from the Pu/Th fueled LWRs
could also be utilized to fuel dispersed reactors. At this point the first phase of a
nuclear power system that includes reactors operating both in energy centers and at dis-
persed locations outside the centers would be in effect.
LWR-LEU DENATURED LWR
WRW REPROCESSING DENATURED
Q F [ Q E THOREX L LWWhITh REPROCESSING
0
I I
,e--\
\ L INITIALPHASE
DENATURED LWR
' LWR-LEU 1
ADVANCED
'\
I
/
CONVERTER
'--4' 1-1
WREX REPROCESSING
THOREX REPROCESSING 1 DENE:FIED
FIR hRh
I
b. INTERMEDIATE PHASE 'n
DENATURED FIR
WRW REPROCESSING
FBR hITh
fi FINALMWE
Fig. 7.3-1. Three Phases for an
Evolving Energy Center.
During this phase, which is
represented in Fig. 7.3-la, the research
and development that will be requirea to
deploy Pu-fueled FBR transmuters with
thorium blankets in the energy centers
could be pursued. .
With these advance preparations
having been made, by the time conventional
LEU fueling in LWRs begins to phase out
(due to increasing depletion of an eco-
nomical resource base), the power system
would evolve into a fast/thermal combination
employing FBR transmuters and 233U-fueled
converters, which by then might include
denatured LWRs and advanced converters (SSCRs ,
HTGRs, or HWRs), depending on the reactor(s)
selected for development (see Fig. 7.3-lb).
Such a system could provide adequate capacity
expansion for modest energy demand growth;
however, if the energy demand is such that
the fast/thermal system is inadequate, an
all-fast system including denatured FBRs could be substituted as shown in Fig. 7.3-lc.
The necessity of the third phase of the energy center development is uncertain at this
time, reflecting as it does assumptions concerning the supply of economically recoverable
U308 and energy demand.
It is noted that this proposed scheme for implementing the denatured fuel cycle and
instituting the energy center concept relies heavily on two strong technical bases:
currently employed LWR technology, and the research and development already expended on
LMFBRs, which includes the Purex and, to a lesser extent, the Thorex reprocessing
technologies. While a1 ternative fuel cycle technologies or other types of reactors will
be involved if they can be demonstrated to have resource or economic advantages, the LWR-
LMFBR scenario has been selected as representative of the type of activity that would be
required.
L
c
L
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