Re:A tale of two particles: Not all radioactivity is risky o...
by credit_guy on Tuesday December 06, 2022 @10:49PM
(#33890431)
> Fabricating quality MOX that be fed back into reactors
MOX can be fed back only once. After that too much Pu-240 accumulates, and that's a non-fissile element that absorbs a lot of neutrons, so it's a neutron poison (see [1]). Pu-240 can't be separated from Pu-239, except using the same methods to separate U-235 from U-238 (but more difficult, since the relative atomic mass difference is much smaller). If you get into the business of isotope separation, you might as well enrich Uranium.
Re:A tale of two particles: Not all radioactivity is risky o...
by PaulHoule on Wednesday December 07, 2022 @08:16AM
(#33893976)
With a fast reactor you can keep the cycle going. Russia is recycling MOX with the BN-800 fast reactor. The U.S. did it too with the FFTF but the FFTF dumped the heat to the air without trying to produce power. Oddly, this makes the FFTF look more like a future fast reactor because the heat exchanger for the FFTF looks more like the heat exchanger for a low capital cost closed cycle gas turbine.
Re:A tale of two particles: Not all radioactivity is risky o...
by Schroedingersat on Wednesday December 07, 2022 @05:44PM
(#33901444)
> Russia is recycling MOX with the BN-800 fast reactor
Source? I was aware it was using MOX, but did not see any discussion over whether it was weapons derived, PWR SNF, from the breeding blanket, or twice used MOX
That said, there might be some other way to make MOX, or some other fuel formulation based on molten salts, metal fuel, nitrides, carbides, etc.
As for economics a big problem is that the LWR works at low temperatures and requires a huge steam turbine and huge heat exchangers. This is apart from the problem that large LWR construction projects frequently go over schedule and budget by a large margin. There is some hope that a smaller reactor like China's ACP-100 can find some simplification at small scale that makes up for the diseconomies of small scale and avoids the project management problems but it will take some kind of water-free reactor that operates at higher temperatures for nuclear to be competitive with natural gas.