ORNL-TM-7207 - the Molten Salt Energy Technologies Web Site

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large uncertainty is present in this estimate, of course, because of the
limited experience in decommissioning. However, the cost sf decommission-
ing does not appear to be a large fraction of the cost of the construc-
tion, and the present worth of expenditures to be made in the future is
small. 'Fhe present worth of the estimated cost of decommissioning a DMSR
40 years after start-up, discounted to the start-up date at a 4.5% dis-
count factor, would be about $15 million.
5.3*4 Fuel cvcle costs
A% this stage of development and optimization of a ~n~e-through DMSR,
several assumptions are necessary if a fuel cycle cost is to be estimated.
One assumption 1s that the initial fuel charge will consist of 74
mole 2 7LiF, 16.5 mole % BeF2, 8.23 mole 2 ThF4, and 1.27 mole X UF, plus
UP3. If, as seems reasonable, an afkswanee is made for an additional 2%
of molten fuel in the drain tank, the initial fuel solvent will require
149 metric tons of ThF,, E13 metric tons of LiF, and 45.6 metric tons of
BO2"
quired; this is equivalent to 804 metric tons of U308 and would require
8.05 x 105 swu for its enrichment.
actor storage tank would consist of 33.1 metric tons (7.30 x ~ b 05 )
material
In addition, 23.5 metric tons of UP, enriched to 20% in 23% is re-
Tke purified fuel delivered to the re-
Total cost of the initial fuel is based on U308 at $35/lb, separative
work at $SO/SWU, BeF2 at $15/lb, thorium at $15/kb Tho2$ and SLiF available
at $3Jg of contained ki,
* AII additional $2/lb of tetrafluoride has
been allotted for conversion of Tho2 to n F4 and for CQrWerSiQn of UPg to
UF$. The fuel, wade by mixing the powdered ingredients, must be purified
in the molten state before use (as described in previous sections), Given
the component fluorides at the prices above, the assunaption is that this
purification can be performed for $$/lb of finished product.
With these assumptions, the total cost of the initial DMSR fuel
charge is near $225 million (see Table 35). If we assme that the annual
* his is the official price for small quantities of ~9,99+ a ~ i
for
use in PWRS. It is almost certainly too high (probably five-fold) if
lithium were actually used in such quantities.