favorable for a safe operation under steady-state conditions. A comparative analysis
of control rod ejection scenarios has also been performed, and it was found that the
maximum values obtained for fuel and clad temperature and maximum fuel
enthalpy are in line with the acceptance criteria for the current generation PWRs.
After 10 years of research sponsored through the EURATOM programs, the
following conclusions can be drawn regarding the behavior of Th-MOX fuel in
LWR conditions:
• Th-MOX has great potential and its fabrication as an oxide fuel is feasible
• Even at a laboratory-scale production route, Th-MOX shows a good in-pile
performance
• Know-how on Th-MOX has increased, but
• Fuel performance obviously needs to be further improved before code calculations can predict specific Th-MOX behavior
As a general conclusion, the results of these experiments have shown that
Th-MOX behaves in a comparable way (even better in some aspects) to MOX,
and that licensing Th-MOX in a LWR should not be problematic, although more
experimental data on fuels representative of the future commercial fuels would be
needed. Experimental data also demonstrate that Th fuels will be more resistant to
corrosion than U fuels in the case of spent fuel geological disposal.
18.4 The Molten Salt Reactor
The MSR, which incorporates the reprocessing on line and needs no specific Th
fabrication, adds the benefits of Th without its main challenges. In particular,
breeding may be achieved over a wide range of neutron energies, which is not the
case for the U-Pu cycle.
Under the European Framework Programs, conceptual developments on fast
neutron spectrum molten salt reactors (MSFRs) using fluoride salts open promising
possibilities to exploit the
232 Th233 U cycle. In addition, they can also contribute to
significantly diminishing the radiotoxic inventory from present reactor spent fuels,
in particular by lowering the masses of transuranic elements. Finally, if required
because of expansion of nuclear electricity generation breeding beyond the
iso-generation could be achieved. With the Th-U cycle, doubling times values are
only slightly higher than those predicted for solid-fuel fast reactors working in the
U/Pu cycle (in the range 40–60 years). The characteristics of different launching
modes of the MSFR with a thorium fuel cycle have been studied, in terms of the
safety, proliferation, breeding, and deployment capacities of these reactor
configurations [10].
Between Framework Programmes 5 and 7, several projects (“MOST”,
“ALISIA”, “EVOL”) were conducted, and promising developments and results
were obtained in particular in the following areas:
202
D. Haas et al.
of control rod ejection scenarios has also been performed, and it was found that the
maximum values obtained for fuel and clad temperature and maximum fuel
enthalpy are in line with the acceptance criteria for the current generation PWRs.
After 10 years of research sponsored through the EURATOM programs, the
following conclusions can be drawn regarding the behavior of Th-MOX fuel in
LWR conditions:
• Th-MOX has great potential and its fabrication as an oxide fuel is feasible
• Even at a laboratory-scale production route, Th-MOX shows a good in-pile
performance
• Know-how on Th-MOX has increased, but
• Fuel performance obviously needs to be further improved before code calculations can predict specific Th-MOX behavior
As a general conclusion, the results of these experiments have shown that
Th-MOX behaves in a comparable way (even better in some aspects) to MOX,
and that licensing Th-MOX in a LWR should not be problematic, although more
experimental data on fuels representative of the future commercial fuels would be
needed. Experimental data also demonstrate that Th fuels will be more resistant to
corrosion than U fuels in the case of spent fuel geological disposal.
18.4 The Molten Salt Reactor
The MSR, which incorporates the reprocessing on line and needs no specific Th
fabrication, adds the benefits of Th without its main challenges. In particular,
breeding may be achieved over a wide range of neutron energies, which is not the
case for the U-Pu cycle.
Under the European Framework Programs, conceptual developments on fast
neutron spectrum molten salt reactors (MSFRs) using fluoride salts open promising
possibilities to exploit the
232 Th233 U cycle. In addition, they can also contribute to
significantly diminishing the radiotoxic inventory from present reactor spent fuels,
in particular by lowering the masses of transuranic elements. Finally, if required
because of expansion of nuclear electricity generation breeding beyond the
iso-generation could be achieved. With the Th-U cycle, doubling times values are
only slightly higher than those predicted for solid-fuel fast reactors working in the
U/Pu cycle (in the range 40–60 years). The characteristics of different launching
modes of the MSFR with a thorium fuel cycle have been studied, in terms of the
safety, proliferation, breeding, and deployment capacities of these reactor
configurations [10].
Between Framework Programmes 5 and 7, several projects (“MOST”,
“ALISIA”, “EVOL”) were conducted, and promising developments and results
were obtained in particular in the following areas:
202
D. Haas et al.