3 ms·
I believe the 20% threshold was chosen because that represents the largest plant and processing cost step in enrichment. In other words once it is at 20% you c
by jhayward 11y ago
I believe the 20% threshold was chosen because that represents the largest plant and processing cost step in enrichment.
In other words once it is at 20% you can use a much smaller enrichment plant to take it to weapons level due to the nature of the cascade. My back of the envelope calcu-guess is that 20% enriched represents about 95% of the work on the way to weapons grade. [edit: guess based on only isotope ratios, not any specifics of yield of the various enrichment processes]
- gh02t 11y agoThe calculations for it are a little weird and involve a rather strange unit called the SWU (separative work unit) and which is actually independent of the separation process, but it works out to be more like ~75% of the effort to go from natural -> 20% enriched as it is to go from 20% -> 95%. You still need the raw mass though. To get enough weapons-grade uranium for a bomb (~15kg) from 20% enriched feed stock and discharging 2% enriched depleted uranium waste you need about 65kg of 20% enriched. So 10kg (assuming it's 20%) is definitely concerning, but it's not enough to make a bomb.
- jhayward 11y agoThis is a late reply but for posterity readers I was able to learn a lot from this article [1]. I'm still not certain how to interpret the 3rd graph in terms of relative work or cost for the 20% vs 90% enrichment levels. [1] http://www.world-nuclear.org/info/nuclear-fuel-cycle/conversion-enrichment-and-fabrication/uranium-enrichment/ http://www.world-nuclear.org/info/nuclear-fuel-cycle/convers...