- No Greenhouse Gas Emissions
- Near Complete Fuel Usage – less than 2% unused fuel is a significant source of valuable substances- Current reactors use only 5% of the fuel. So LFTRs leave 2% behind and can effectively manage the left over fuel. Far shorter half life (a few hundred years) The current reactors leave 95% behind and leave it for storage and the half life amounts to thousands of years. The storage is handled well but the full elimination of “waste” is more desirable for political reasons.
- energy density is much greater than Uranium largely because of complete fuel usage being possible in a liquid state.
- the more toxic fission products such as plutonium never get produced
- 2 or more plants in one – reprocessing and energy production and secondary applications are all feasible
- underground designs have been suggested
- underwater designs are a favorite of Kirk Sorensen
- water desalinization
- hydrogen production
energy=industry=jobs=education=birth control=population control
Quoted from Charles Barton’s Nuclear Green Blog post on Single Fluid MSR Design Disadvantages
“David LeBlanc notes some of the disadvantages of the Single-fluid breeder:
1. Fission product processing greatly complicated by the presence of Thorium
2. Higher neutron leakage
3. Weakly positive temperature coefficient, can be fixed but at large cost
4. Pa removal needed unless both thorium and 233U loading increased substantially
Point 3 above is important to discuss. A positive temperature feedback coefficient is generally a bad thing for any reactor design. It is not as serious as may be thought however since the positive term results from effects of the graphite which will lag behind any temperature increase in the salt by tens of seconds at least. Original ORNL work thought it to be slightly negative, recent French studies have shown that to be mistaken. This was mainly due to older calculations treating the graphite and salt mix as homogeneous. In order to solve this problem without destroying the ability to breed, French proposals have gone the route of having an extra Thorium blanket around the core (radial only, not axial). This make it a partial 1 and 1/2 Fluid reactor.
The problem which has been the focus of much attention by French researchers, is that ORNL’s single fluid MSBR had a safety flaw in the ORNL one fluid design that if not corrected, could cause loss of control in the ORNL designed one fluid MSBR. This flaw is probably not fatal, but the French seem anxious to not simply replicate ORNL research, so they have made a big deal of it, and at any rate some, but by no means all, reactor design specialists are concerned enough to write off the one fluid graphite moderated MSRs.
ORNL reactor scientists were not all in agreement on the superiority of the single fluid MSBR design. Many continued t0 believe that the two fluid approach offered advantages.
More Cons for the Dual Fluid Design also post at Nuclear Green
* Interlacing of fuel and blanket salt within core is the “Plumbing Problem”
* Blanket salt has positive temperature/void coefficients
* Need for extra heat transfer loop for the blanket salt (5-10% of heat load)”
in the meantime Charles Barton has started a series on Molten Salt Reactors which in general are about Thorium Molten Salt Reactors. He covers the PROS and CONS of each.