Timeline for Help! An 8 year old asked me how to build a nuclear power plant
Current License: CC BY-SA 3.0
11 events
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| Apr 13, 2017 at 12:39 | history | edited | CommunityBot |
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| Mar 19, 2016 at 23:56 | history | edited | RedGrittyBrick | CC BY-SA 3.0 |
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| Mar 19, 2016 at 8:34 | vote | accept | crestmods | ||
| Mar 18, 2016 at 20:23 | comment | added | Dan Is Fiddling By Firelight | @RedGrittyBrick gas centrifuges are the best method for enriching it; but the Manhattan project also put two other methods other methods into production during WW2: Electromagnetic separation via cyclotrons, and gaseous thermal diffusion although IIRC the amount of time the cascades for the latter needed to reach equilibrium was long enough that it was only used to produce moderately enriched uranium as an input material for the other processes. | |
| Mar 18, 2016 at 18:26 | comment | added | hobbs | @RedGrittyBrick yes, for practical purposes. Natural uranium is less than 1% U-235. Fission reactors use uranium that's been enriched something like 5% U-235, while material for bombs is usually enriched to 80%, 90%, or more. So there's a huge difference in the degree of enrichment, but the process is the same, and the reason for it is the same. | |
| Mar 18, 2016 at 17:04 | comment | added | rob♦ | A natural reactor would use natural water ($\rm H_2O$); according to your link a reactor using natural uranium must use heavy water, $\rm D_2O$, or graphite to slow down the neutrons. (However you can't use pencil-lead graphite, which is usually contaminated with boron.) | |
| Mar 18, 2016 at 15:15 | history | edited | RedGrittyBrick | CC BY-SA 3.0 |
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| Mar 18, 2016 at 15:12 | comment | added | RedGrittyBrick | @rob: I started to update my answer but realised I don't understand this stuff well enough. Are gas centrifuges needed if you are not making a bomb? I read that natural Uranium is adequate for power stations (but I don't know how the ore is processed) - maybe you could update my answer (I can make it community wiki if you like), or write another (I can delete this one if your answer would be a superset) | |
| Mar 18, 2016 at 15:09 | history | edited | RedGrittyBrick | CC BY-SA 3.0 |
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| Mar 18, 2016 at 12:17 | comment | added | rob♦ | Note that the Oklo natural reactor was last active ~2 Gyr ago. Uranium-235, which can go critical when immersed in water, has a shorter lifetime than U-238, so all natural uranium is now "less enriched" in U-235 than in the past and a natural reactor is no longer possible on Earth. This falls under the umbrella of "you need to separate out the right kind of rock." The way it's done in practice --- centrifuge separation of UF$_6$ gas by uranium mass --- is far enough from "grinding up the rock" to warrant a place in the explanation. | |
| Mar 18, 2016 at 11:05 | history | answered | RedGrittyBrick | CC BY-SA 3.0 |