Cheers.

http://bravenewclimate.com/2010/04/22/ifr-fad-4/#comment-58025

“”Others counter that actinide removal would offer few if any significant advantages for disposal in a geologic repository because some of the fission product nuclides of greatest concern in scenarios such as groundwater leaching actually have longer half-lives than the radioactive actinides. The concern about a waste cannot end after hundreds of years even if all the actinides are removed when the remaining waste contains radioactive fission products such as technetium-99, iodine-129, and cesium-135 with the halflives between 213,000 and 15.7 million years” [6]”
http://en.wikipedia.org/wiki/Integral_fast_reactor

The quote seems to come from Page 30 on this Google books record.
http://books.google.com/books?id=Lr0sPxjBD2MC

Bill, thanks for those slides from Loewen. Close inspection of slide 3 leaves me much clearer on the pyroprocessing processes, too.

So, you could make some clandestine Pu, but how much? It takes about a gram of fissile material to produce a megawatt-day of energy. So the entire breeding blanket of a 400 MW (thermal) PRISM module would be producing about 150 kg per year of Pu, assuming it was operated for replacement. To get a weapon’s worth in a year (around 3 kg) you would have to have an extra 2 percent of blanket clandestinely inserted, and that would be at the average blanket radius. Out towards the periphery of the system, you’d need much more volume because the blanket is designed to use as much of the neutron population as possible. Pickings are much slimmer out there.

The PRISM presentation is at

http://local.ans.org/virginia/meetings/2007/2007RIC.GE.NRC.PRISM.pdf

But if you want to come here and start personally insulting one of my respected, regular commenters, with name-calling, then you have no place here. Take it as a friendly warning.

this additional role of IFRs is obviously highly desirable from multiple standpoints (elimination of the long-lived ‘waste’ problem and proliferation reduction)

Maybe one can reduce the theoretical potential for power reactors to be involved in proliferation, but their actual history of involvement is zero, and so not subject to reduction.

This potential remain like that of car engines to be made into multibarrel cannons: it could happen, and guns do proliferate, but never that way.

(How fire can be domesticated)

The emphasis on sodium-cooled reactors here is: (i) because they well tested thanks to the Argonne programme and are on the cusp of deployment (the S-PRISM demonstrator reactor that can be used to ‘prove up’ the economic prospects of IFR is designed by GE/Hitachi and ready to build!) and (ii) IFRs will be very effective at gobbling current stockpiles of nuclear waste, purified plutonium and extract a heap of useful energy from the piles of depleted uranium sitting around not doing much apart from armouring a few M1A2 Abrams tanks — this additional role of IFRs is obviously highly desirable from multiple standpoints (elimination of the long-lived ‘waste’ problem and proliferation reduction).

Thorium is abundant, especially in places like India (their beaches are loaded with it) and there is no theoretical reason why MSR won’t be working alongside SCR (or other types such as lead cooled, gas cooled or even supercritical water reactors). It is also the most abundant heavy element in coal slag (ironic that the slag from a coal-fired power stations contains more energy in the thorium that’s thrown away than was liberated from burning the black carbon).

Charles Barton runs a super website called “Energy from Thorium“. I highly recommend taking the time to explore its details on the MSR and its future prospects.