Talk:Reactor-grade plutonium

Hey! There's no actual definition of reactor-grad plutonium here. Specifically which two or more isotopes does it contain? Qwertie (talk) 23:53, 19 June 2016 (UTC)

Details

It would be very interesting to know:

• the date of this particular test

• the series and/or name of this test

and probably knowing either will give us the other, see

http://www.ga.gov.au/oracle/nukexp_query.html

It would also tell us whether or not this test is already listed at List of nuclear tests#1945–1963, and enable us to link the list to this page. Andrewa 00:02, 4 June 2007 (UTC)

From my research it appears highly likely to be test shot Tendrac of Operation Storax as I've detailed in the article of late, as that was an US-UK joint test, it was one of two joint tests conducted in 1962, and it's cited yield was "low", which is identical to the description of the yield by the Carter Administration in 1979. I'm not ruling out the possibilty that it might have been some other unlisted US test in 1962, but Tendrac would be my best bet. I find it curious why no one else has ever uncovered Tendrac of Operation Storax as the most likely culprit, as it really wasn't that hard to look up all US tests.

I've thought about looking up 1962 seismic data collected by numerous sources to see if I can get a ballpark value of the yield, but I've put that on the long finger as it would probably take an hour or two to find and analyze and my spider sense tells me it was probably no more than 9 kilotons, with the most likely being ~2 kiloton, but that's just a guess going on the data from the N.Korean tests of late.

On a related note, surely there is a burn up rate(+100 GWd/tU maybe) that would result in the reactors plutonium content being too low in Pu-239 & Pu-241 to create even a fizzle nuclear explosion, right? Something akin to the respective, Uranium 20% enriched U-235 value, with anything below that 20% being considered LEU and therefore that isotopic mixture being regarded as not directly "weapons-usable". Although that 20% appears pretty conservative, as I'd bet the practical value is around 40% enriched uranium, and below which it wouldn't create an explosion either. Uranium hydride bomb data would probably be highly relevant to that question.

Why a similar value for plutonium isn't available I know is due to "national security", but surely it occurs when the Pu-238, Pu-240 and Pu-242 values get up into the 15+% range and the combined Pu-239 & Pu-241 percentage drops below 40%. I have read that plutonium with 80% Pu-238 is not regarded as weapons-usable, but that, like the definition for LEU, seems pretty conservative, I'd be surprised if the practical "non weapons-usable" percentage wasn't a good bit below that.

86.41.146.36 (talk) 19:55, 11 December 2013 (UTC)

There's a handy table of Pu-isotopes content of spent fuel at various burnups, including Magnox, on page 19 of the UK Pu Options doc.[1] Would probably interest you. (This doc has a full cite in the MOX fuel article as [12].) Rwendland (talk) 02:09, 12 December 2013 (UTC)

Thanks, I'll take a look at that!

Some info on the UK Totem/Totum tests (part of Operation Totem 1953) would probably make the article less US centered.

http://left-atomics.blogspot.ie/2008/08/two-four-six-eight-we-dont-want-to.html

http://theenergycollective.com/charlesbarton/28509/nuclear-proliferation-devices-and-weapons

Isotopic characteristics of Totem devices (1963 UK tests): http://www.aps.org/units/fps/newsletters/1996/october/aoct96.html#a2

It would appear that N.Korea's more recent (2009-2013) nuclear tests coincide fairly well with the yield of Totem I & II conducted way back in 1953. This is probably no coincidence seen as both were seemingly produced by magnox reactors.

Improvements

Mention to the fact that all the concern coming from Ted Taylor etc back in the 1970s was during an era when the best burn-up value acheivable for a PWR was ~ 20 MWh/ton. It is now over twice that. As can be seen in the IAEA's nuclear power status 2005 picture found here. In non-pdf form, although you can always look the full pdf up if you are skeptical.

Secondly, books & journal papers with the following term: "HNED's" hypothetical nuclear explosive device. Should be included. Like this paper by Kessler in 2008 HNED potential

Thirdly, Cohen has a good article on the apprehension surrounding the terrorist use of this material that should have its points mentioned. http://www.phyast.pitt.edu/~blc/book/chapter13.html#1

Fourthly, mention to the isotopic ratio of reactor grade plutonium(of typical burn-up values) after 100,1000 & 10,000 years is required as there is the issue that if geological repositories are implemented for the spent fuel of typical PWRs/BWRs etc*, then in the future these repositories would turn into weapons-grade plutonium mines due to the relatively fast decay of Pu-238 to leave Pu-239 etc, and that's to say nothing about the even more concerning suggestion of putting MAGNOX & AGR spent fuel* directly underground.

Fifthly, that breeder reactors like the Phénix reactor etc have demonstrated, on 1 hand, the ability to burn-up, MOX with 3 recycles, thus rendering the term "reactor grade" stretched to much lower Pu-239 values. While on the other hand, papers in science and global security(S&GS) have analyzed the Russian BN-800 reactor as producing pretty-much weapons grade plutonium in their core blanket fuel/various geometries. | here's the paper. Moreover the Indian PFBR would rather have RgPu over WgPu as to start with Pu-240 breeds Pu-241, a superior fuel to Pu-239 & S&GS have also analyzed its ability to also breed WgPu.| here(PDF). While I find Ramana & S&GS rarther, selectively antagonist towards breeder reactors, they seem to my untrained eye, produce reliable calculated data.

lastly, the varying weapons "attractiveness-level" of breeder reactor spent fuel, pg 4-5 of this JAEA pdf — Preceding unsigned comment added by 92.251.153.186 (talk) 10:05, 10 July 2015 (UTC)