Here's a quick explanation:
Uranium ore is just rocks with some uranium in it.
The uranium extracted from ore is called "natural uranium".
Natural uranium is only 0.7% U-235, it has to be enriched to about 3-5%, roughly a 5 to 1 ratio.
So a ton of natural uranium only gets you about 1/5 ton of enriched uranium for fuel rods.
The uranium in fuel rods gets transmuted into all kinds of nasty stuff in a reactor, Garwin estimates below that it takes about seven used uranium fuel rods to make one usable MOX fuel rod, which is in the 12-17% range you mention. A used MOX fuel rod cannot be recycled because it gets transmuted into even worse crap.
So of the original natural uranium from mining, only about 1/7 of 1/5 can be reused; 1/7 of 1/5 is 1/35, which is roughly 3%.
"Recycling" is just a PR term the industry uses to confuse people; the amount "recycled" is so low, it's not an intellectually honest term, especially since the "recycled" MOX fuel can't be "recycled" again, the way you can recycle things like aluminum over and over again.
http://www.ips-dc.org/articles/nuclear_recycling_fails_the_testNuclear Recycling Fails the Test
July 2, 2008 · By Robert Alvarez. Edited by Miriam Pemberton
The debate over nuclear power is heating up, along with the planet. Can nuclear fuel recycling be part of the mix? Not a chance.
<snip>
In 2007 the International Atomic Energy Agency concluded that “reprocessed uranium currently plays a very minor role in satisfying world uranium requirements for power reactors.” In 2004, about 2 percent of uranium reactor fuel in France came from recycling, and it appears that it now has dwindled to zero. There are several reasons for this.
Uranium, which makes up about 95 percent of spent fuel, cannot be reused in the great majority of reactors without increasing the levels of a key source of energy, uranium 235, from 1 to 4 percent, through a complex and expensive enrichment process.
Reprocessed uranium also contains undesirable elements that make it highly radioactive and reduces the efficiency of the fuel. For instance, the build up of uranium 232 and uranium 234 in spent fuel creates a radiation hazard requiring extraordinary measures to protect workers. Levels of uranium-236 in used fuel impede atom splitting; and to compensate for this “poison, recycled uranium has to undergo costly “over-enrichment.” Contaminants in reprocessed uranium also foul up enrichment and processing facilities, as well as new fuel. Once it is recycled in a reactor, larger amounts of undesirable elements build up – increasing the expense of reuse, storage and disposal. Given these problems, it’s no surprise that DOE plans include disposal of future reprocessed uranium in landfills, instead of recycling.
<snip>
As a senior energy adviser in the Clinton administration, I recall attending a briefing in 1996 by the National Academy of Sciences on the feasibility of recycling nuclear fuel. <snip>
But then came the Academy's unequivocal conclusion: the idea was supremely impractical. <snip> Ten years later the idea remains as costly and technologically unfeasible as it was in the 1990s. In 2007 the Academy once again tossed cold water on the Bush administration’s effort to jump start nuclear recycling by concluding that “there is no economic justification for going forward with this program at anything approaching a commercial scale.”
<snip>
http://thebulletin.org/web-edition/op-eds/reprocessing-isnt-the-answerReprocessing isn't the answer
By Richard L. Garwin | 6 August 2009
<snip>
Some commercial interests argue that such spent nuclear fuel should be reprocessed (or "recycled," which is the industry's current term) into fresh fuel. They claim that this will greatly reduce the need for mined uranium and for underground repositories, and is, in any case, desirable--just as is all recycling of material such as paper, glass, aluminum, and steel. In reality, however, recycling spent nuclear fuel from U.S. reactors wouldn't solve any problems and would add additional cost and hazard.
In my congressional testimony, speeches, and published articles, I have provided technical details and abundant references to explain my opposition to reprocessing of LWR fuel back into fresh fuel as is practiced in France and a few other countries. France has decades of experience in technically successful reprocessing of its LWR spent fuel. It currently obtains one usable mixed-oxide (MOX) fuel element, a mixture of plutonium and uranium oxides, from every seven LWR spent fuel elements. But aside from the almost 1-percent plutonium in the spent fuel and the 94-percent uranium 238, the other 5 percent of mass (called "fission products") is removed and melted together with glass into a vitrified product that is encased in welded stainless steel canisters. These are stored at the French reprocessing plant at La Hague, awaiting the availability some decades hence of a mined geologic repository. In fact, for all the U.S. delays and roadblocks, it's far ahead of France in planning for a permanent repository.
In truth, reprocessing doesn't eliminate or even significantly reduce the need for a repository, as demonstrated by the authoritative presentations of Idaho National Laboratory Associate Director Phillip J. Finck, who has worked in the French program and is now in charge of a major portion of the U.S. government nuclear energy research program. According to Finck, Yucca Mountain could accommodate only about 10 percent more spent MOX fuel and vitrified fission products as produced at La Hague than it could normal spent fuel. This is because after four years in a reactor MOX fuel is much hotter than normal spent fuel, and so fewer spent MOX fuel elements can be accommodated in the same space as ordinary and cooler spent fuel (also called UOX, for its uranium-oxide content).
<snip>
This has gotten a lot of attention in France because of a recent tv documentary:
http://www.fissilematerials.org/blog/2010/02/a_french_documentary_on_n.htmlA French documentary on nuclear waste
By Mycle Schneider on February 22, 2010 11:10 AM |
<snip>
Parliamentary enquiry, government statements, Greenpeace actions are a few of the stunning consequences of a 100-minutes TV documentary Déchets - Le Cauchemar du Nucléaire (Waste - The Nuclear Nightmare) broadcast by the Franco-German station ARTE for the first time on 13 October 2009 and re-broadcast by various television stations since. The documentary presents the results of an investigation into nuclear waste management in the US, Russia, Germany and France.
<snip other parts of the documentary>
However, remarkably enough, the largest impact had a simple mass calculation that the journalists presented. Constantly facing the AREVA PR that states that 96% of the nuclear materials are "recycled" through the reprocessing scheme, the reporters inquired where the recovered uranium, roughly 95% of the mass of spent fuel, does end up. In fact, AREVA has been sending most of the reprocessed uranium (23,000 tons were still stored in France at the end of 2008), to Russia officially for re-enrichment. In fact, even if all of that uranium had indeed been re-enriched, which is not the case, over 90% of the mass remains in Russia as enrichment tails. This material is waste, because there is absolutely no economic incentive to re-enrich it, in particular considering the hundreds of thousands of tons of "clean", first generation enrichment tails that are stored in Russia and in the other major enrichment countries, including in France (close to 260,000 tons at two sites).
The message that AREVA's "recycling" ratio had to be corrected from 95% to less than 10% of the original mass send a shockwave through the French political landscape. The minister of Environment asked for clarifications and the parliamentary Office for Scientific and Technological Option Assessment (OPECST) organized public hearings. During the hearings EDF has admitted that, apart from a period of about five years, 100% of the reprocessed uranium had been sent to Russia. Between 2000 and approximately 2005 (the EDF representative was not certain) reprocessed uranium was sent to URENCO's Dutch plant that can re-enrich reprocessed uranium (contrary to URENCO's UK and German plants). EDF signed a contract with AREVA to use part of the Georges-Besse-2 plant, currently under construction, to enrich reprocessed uranium for a period of about 10 years starting in 2013. The French Nuclear Safety Authority ASN announced that by the end 2010 it will have finished studies into the potential requalification of reprocessed uranium as waste.
The full version of the film "Déchets - Le Cauchemar du Nucléaire", by Eric Guéret and Laure Noualhat (in French and German with English subtitles) is available online. ARTE-Editions has also published a 210-page book by Laure Noualhat with the same title (in French). It can be ordered here.
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