Talk:Nuclear fuel cycle
|WikiProject Energy||(Rated C-class, Mid-importance)|
|WikiProject Occupational Safety and Health||(Rated C-class, Low-importance)|
- 1 Terminology
- 2 Merging Nuclear reprocessing with Nuclear fuel cycle
- 3 NPOV!
- 4 Global Nuclear Energy Partnership
- 5 Isotropic signature of Pu
- 6 Unclear passage
- 7 I rewrote the introduction
- 8 Great image if you can translate French
- 9 Cleanup
- 10 Transport references
- 11 Thorium abundance
- 12 Diagrams
- 13 Neptunium
- 14 We will not be beaten!
- 15 I am adding a new introductory section for the layman
- 16 It's not a cycle
- 17 Support the images by quantities
- 18 No mention of Russia or France
- 19 Additional topics
(section titled added by J.Ring 03:11, 25 September 2006 (UTC))
I think that the term "Nuclear fuel cycle" should include the period spent by the fuel into the reactor. At least, during my working life concluded by a period of 15 years as national manager of Nuclear fuel procurement, operating optimization, reprocessing, storage, waste management, etc., the meaning usually given to the "cycle" included that period. I'm asking if there is a general agreement on this issue, before proposing changes to the article. Paolo de Magistris,Rome, Italy. --184.108.40.206 13:25, 25 Nov 2004 (UTC)
- There does seem to be a huge gap in information right in the middle of the article, doesn't there? Simesa 18:08, 1 October 2005 (UTC)
- I took the liberty of fixing this oversight. DV8 2XL 05:53, 6 October 2005 (UTC)
Merging Nuclear reprocessing with Nuclear fuel cycle
- Refer to Talk:Nuclear reprocessing for discussion on this issue.
- This has now been done DV8 2XL 04:39, 6 October 2005 (UTC)
I think the "nuclear fuel chain" is not neutral pictured!--Enr-v 10:46, 25 January 2006 (UTC)
- What's your problem with it?--Fastfission 18:03, 25 January 2006 (UTC)
- I have altered the article to make it more NPOV, I have also added details of the three main fuel cycles which are possible.Cadmium 18:11, 30 January 2006 (UTC)
- If material is taken out of the ground, used and returned to the ground it's still a cycle, no? --DV8 2XL 20:57, 30 January 2006 (UTC)
- no, it doesn't become the original material anymore once it is in the ground. A cycle that is open is a chain. --SvenAERTS (talk) 22:25, 8 December 2012 (UTC)
- no, it is a chaîn, because uranium taken out of the ground is different from used nuclear fuel and radioactive waste. Moreover radioactive waste are mostly not returned to the ground. couldn't you draw a better scheme? --Enr-v 13:01, 31 January 2006 (UTC)
- If someone agrees upon a good "cycle", I'd be happy to make it/them beautiful looking. --Fastfission 18:28, 7 February 2006 (UTC)
In February, 2006, a new U.S. initiative, the Global Nuclear Energy Partnership was announced - it would be an international effort to reprocess fuel in a manner making proliferation infeasible, while making nuclear power available to developing countries. Would someone like to blend GNEP into this article? Simesa 20:59, 9 February 2006 (UTC)
- Done. Hey Simesa, who was your wiki secretary last year? --DV8 2XL 21:07, 9 February 2006 (UTC)
- To be honest, I didn't want to be accused of spreading this all over the place, and I wanted a second opinion as to whether this new program should be mentioned. Thanks for putting it in. Simesa 01:02, 10 February 2006 (UTC)
- Done. Hey Simesa, who was your wiki secretary last year? --DV8 2XL 21:07, 9 February 2006 (UTC)
Isotropic signature of Pu
That looks very very strange. Isotopic, maybe... but even tehre, it owuld be better to be definite about what the usefulness of Pu that has been through several cycles will be. At worst I suppose one would end up separating it like U235 from 239, but I can't see a mechanism for Pu239 to absorb neutrons, and then become unfissile - it is more likely to be either split, or turn into Amrericium etc and decay promptly. I'm taking it out for the moment. By all means enlighten me. Midgley 22:20, 11 March 2006 (UTC)
"It is likely that the fuel will have to be able to tolerate more thermal cycles than conventional fuel, this is because if the accelerator is likely stop working on a regular basis. Each time the accelerator stops then the fuel will cool down, it is normal in many conventional power reactors to run the plant at full power for weeks or months at a time, rather than switching it on and off each day."
I can't make sense of that. I'm sure it should not say what it does, but I'm not sure what it should say. Midgley 22:34, 11 March 2006 (UTC)
Another: "but the ratio of fission to simple activation (ng reactions) changes in favour of fission as the neutron energy increases." I don't understand (ng reactions). COntext or explanation needs adding. Midgley 13:50, 20 March 2006 (UTC)
I rewrote the introduction
I hope nobody minds. I think it is clearer now, and I wanted to link it to this page to the"nuclear fuel" page. Ajnosek 03:15, 23 June 2006 (UTC)
Great image if you can translate French
This image at Commons would be a great addition to the article if was translated (it is an SVG so changing the text would be easy). Though I'm pretty sure I can figure out what everything means, I don't actually know French, so I'm probably not the best person to do it... --Fastfission 15:47, 18 August 2006 (UTC)
Also, one of my long-term goals is to transform all of the flowcharts here to SVG, with little graphics, and make them all vertically oriented so they fit on the page... --Fastfission 15:49, 18 August 2006 (UTC)
The section on minor actinides was almost inconsistent and generally messy. I have tried to clarify it a bit. Also, this article currently doesn't implement the new referencing system properly. I added the ref tags but the references still aren't labelled in the reference section, and to be honest I don't know exactly how it is done. J.Ring 03:16, 25 September 2006 (UTC)
The section on transport appears to have been taken almost verbatim from the Uranium Information Centre's issues paper #51 . Yet it has not been referenced. I don't know what wikipedia's stance is on the matter as I'm just a local peruser. Just thought I'd point it out.
- Thanks, James, this has been fixed. Wes Hermann 19:29, 6 December 2006 (UTC)
I changed a passage stating that thorium is more abundant than uranium. These references on the uranium and thorium resource base show that uranium is about 10x more abundant. However, some countries do have more thorium than uranium, like India. Wes Hermann 19:27, 6 December 2006 (UTC)
Thorium is absolutely more abundant than Uranium, 9.6 vs 2.7, as referenced above. I think you might be confusing abundance with resources. They are not the same thing at all.
Why no discussion of one of the most abundant minor actinides, neptunium? NPguy 02:46, 9 June 2007 (UTC)
We will not be beaten!
Check out the citizendium version of this page. They added an In-core fuel management which is not bad, not bad at all. So I just need the wiki source of it, which I can't get quite yet, but I'll figure it out soon enough. Then it's time for some hard core ctrl+v.
I am adding a new introductory section for the layman
I am going to move the Fuel cycles section to the bottom of the page. It is too details for the layman and not useful shown before all other sections. I am adding a new introductory section modeled after the one I've just added to the Chinese version of this article. Fred Hsu (talk) 21:58, 27 March 2011 (UTC)
- But you don't know the subject. Much of the information is irrelevant, incomplete, and incorrect. NPguy (talk) 00:40, 28 March 2011 (UTC)
- I already responded on my user talk page. Please feel free to correct my mistakes. Thank you for such fast response. I expect nothing less from my fellow Wikipedians. As mentioned on my talk page, I am done editing that section. Fred Hsu (talk) 00:48, 28 March 2011 (UTC)
- I see that you are starting to rewrite it. Thank you. You gave me time to finish. And I will wait until tomorrow to see how you rework it. Paring down is fine, but please don't just chop off stuff like links to other articles and how dual use and nuclear proliferation fits within the fuel cycle. These are important topics and it took me several days to piece together the big picture. You may not deem them 'necessary', but put yourself in the shoe of a layperson. Assume a reader with grad-school-level education who is not well-versed in nuclear technologies. What does a big picture of the 'nuclear fuel cycle' look like? Thanks. Fred Hsu (talk) 02:08, 28 March 2011 (UTC)
- First, NPguy, I thank you for editing my changes. You obviously know what you are writing. I waited for a day, but it appears that you made only an initial change. I will first edit your changes to eliminate obvious typos. Then I will compare it to what I originally planned and propose further changes here. Fred Hsu (talk) 02:14, 29 March 2011 (UTC)
I am back with new proposals to finish the newly created Basic Concepts section. First, I think the newly rewritten version is excellent. But I am not completely satisfied with some relevant information you chopped off:
- MOX and benefits derived from its usage. Elsewhere in the article it is mentioned that recycling of spent fuel can reduce or delay associated problems. Merely mentioning MOX without talking about why is is an 'alternative', I feel, is insufficient for the general public. There has been a recent, ridiculous national outcry in Taiwan and China accusing Japan of producing nuclear weapons derived from reprocessing of fuel (triggered by the Fukushima incident of course). Blogs and newspapers focus on nuclear proliferation issues while not one single person points out any potential benefit of using MOX fuel. As a Taiwanese myself, I feel ashamed that no one is speaking on behalf of the truth, and it does not help that both English and Chinese Wikipedia lack a concise section of the complete fuel cycle. This is in fact what pushed me to research this topic and to write that Basic Concepts section in the first place.
- MOX and nuclear proliferation. Elsewhere in this article it is also mentioned how concerns about nuclear proliferation is the reason why the US does not reprocess spent fuel. It makes sense to have a sentence of two regarding this in the summary section as well.
- The scarcity of uranium, and especially U-235 as the only naturally fissile isotope. Since we are talking about the fuel 'cycle', it seems to me that it is worth mentioning in this summary section, together with or separately from the discussion about recycling of spent fuel. We may as well mention the competing thorium while we are at it. You seem to believe 85 years is plentiful. Perhaps you are right; who knows how fast technology advances (exponentially)... we may not need nuclear power in another 20 years. I will concede this point if you can show me this is the mainstream attitude.
- Let me respond to each of these points in succession:
- 1. The basic concepts section is not the place to address the claimed benefits of MOX fuel. Recycling MOX in thermal reactors has minimal waste management benefits. Recycling in fast reactors has greater potential benefits, but its technical and economic practicality is far from proven. Because the issue is more complicated, it fits better in a more detailed discussion.
- 2. I'm not sure what needs to be said beyond the fact that plutonium can be used to make weapons, which I think is already there. What do you suggest?
- 3. I dispute the claim that uranium resources will run out in 85 years. Recent estimates suggest much larger reserves, and that the once-through fuel cycle is sustainable for many decades even with a dramatic expansion of nuclear power. NPguy (talk) 02:29, 31 March 2011 (UTC)
What I think:
- 1. Potential benefits of recycling fuels for waste management. I don't mean MOX in particular. It is not clear to me why recycling fuel should be an alternative to uranium, if you claim that waste management benefits minimal or is not a realistic goal. Or, is it that nuclear weapons can be converted to MOX instead? In any case, the Basic Concepts *is* the place to succinctly spell out some of these and link to appropriate pages for people who want to pursue these leads further.
- 2. Nuclear proliferation. In your mind you probably can describe a dozen ways reactor-grade fuel can be converted to weapon-grade plutonium. But since you removed all traces of my original wordings on this, a new reader will have zero ideas about this. Again, I feel that the Concepts section *is* the place to succinctly spell this out, pointing people to pages on nuclear proliferation or dual use technology.
- 3. Supply of uranium. As I already said, I won't insist on this. But elsewhere on Wikipedia (e.g. Uranium#Supply) it is said that we have some 85 years. Perhaps that is wrong. Perhaps you can cite other sources. If scarcity of uranium is NOT an issue, then what makes things such as MOX an 'alternative'? Is it cheaper? Safer? I am confident you know the answers. But how is a first-time reader to even approach these questions? The fuel cycle article, in my opinion, is the best place to piece together a coherent picture of all relevant leads.
Humbly yours. 04:06, 31 March 2011 (UTC)
- The way recycling is currently done, in light water reactors, has few if any waste management benefits. The reason is that you can't recycle the plutonium indefinitely. In practice, I don't believe anyone has recycled plutonium more than once. And the resulting spent MOX is so much hotter than spent LEU that it is just as hard to dispose of, even though there is less of it.
- You don't need to convert reactor grade plutonium to weapons grade in order to use it in a weapon. It is directly usable, as is. Weapons grade material is preferred, but not required.
- The article says "at least" 85 years, and other estimates find "an order of magnitude larger resources" at an affordable cost.MIT Update MOX is an alternative to LEU fuel for a light water reactor - i.e. it is another way to fuel such a reactor. It is NOT safer and it is NOT cheaper.
I briefly skimmed through that PDF. Wow. There is a lot of information in that document. I stand corrected on all three issues listed above. Maybe one day when I am motivated again I will come back and enhance it. There is definitely enough information from that document alone to enrich this new section on topics I want to add back, not to mention the 2003 document this one *updates*. Take this one for instance:
Reprocessing and recycle:
A decision to adopt a closed fuel cycle, with reprocessing SNF and recycling the ﬁssile plutonium and uranium into reactors for power and transmutation of long-lived actinides, depends on three factors (1) economics, (2) impact on waste management, and (3) nonproliferation considerations.
It's not a cycle
It should be called a nuclear fuel chain. Calling it a cycle implies that you can get back to where you started, but you can't. Once you fission uranium, you can't get the original uranium back and you can't get rid of the waste fission products. — Preceding unsigned comment added by Jpritikin (talk • contribs) 06:40, 25 June 2012 (UTC)
- Perhaps you are right that it should be called a chain, but the fact is that it isn't; I have never seen anyone use that terminology. Wikipedia is about compiling verifiable information, not expressing individual opinions. If you want to make this claim, find a reliable source that supports it. NPguy (talk) 01:46, 26 June 2012 (UTC)
- "Nuclear fuel cycle" is a term of art. No one says, or writes "nuclear fuel chain" -- at least not that I have seen. It's not about the meaning of the word "cycle." Wikipedia articles are not a place to express opinions. They are for verifiable substantive content. NPguy (talk) 02:57, 28 June 2012 (UTC)
- Alright, I found somebody who makes this argument and added a citation. Now it's not original research. And I think it is important. Jpritikin (talk) 11:20, 4 July 2012 (UTC)
I undid it because it looks like you posted the same comment on a blog and tried to cite that as an independent source. Wikipedia requires reliable sources, and this blog clearly does not qualify. In general, blogs do not qualify, but there are exceptions.
My basic point is that no one cares if the "nuclear fuel cycle" is accurately described as a "cycle." It has become a term of art. Even when there is no attempt to recycle spent fuel, it's called a "once through fuel cycle."
- Is Dr. Helen Caldicott good enough for you? It is not a circular nuclear fuel cycle it is a longitudinal nuclear fuel chain Jpritikin (talk) 07:00, 11 July 2012 (UTC)
- No. A tweet is not a reliable source. NPguy (talk) 02:27, 12 July 2012 (UTC)
- "When taking information from opinion pieces, the identity of the author may help determine reliability. The opinions of specialists and recognized experts are more likely to be reliable and to reflect a significant viewpoint." -- Helen Caldicott is a renown expert on nuclear power. I don't mind explicitly attributing the idea to her. Jpritikin (talk) 02:50, 12 July 2012 (UTC) Also I doubt whether it is possible to find a more reliable source for this point because nobody will likely be published in a peer reviewed journal for such an obvious and unremarkable observation. Jpritikin (talk) 08:28, 12 July 2012 (UTC)
- Of course the word/terminology is important. Cycle is used by pro-nuclear power parties to try to make it sound more like a sustainable ressource. The nuclear chain term is used more by opponents - and is correct vocabulary wise - to demonstrate the material cannot be replaced by our Mother Earth's natural processes. If fossil fuel is not seen as a sustainable fuel, then nuclear power can't at all. Good point. I assume in literature from the environmental movements it's possible to find more references to the terminology Nuclear Chain. Let's look for them. Good point ! --SvenAERTS (talk) 22:21, 8 December 2012 (UTC)
- No. A tweet is not a reliable source. NPguy (talk) 02:27, 12 July 2012 (UTC)
The impression I'm getting is that the terminology is a matter of controversy, which, under certain conditions, would itself be worthy of mention in the article. As in, the industry uses "fuel cycle" without a second thought because it's always been called that and the term is perfectly functional; while opponents wish to call it a "fuel chain" because laymen will construe "cycle" as implying renewability. If this is indeed the situation, it seems obvious to me that the term "fuel cycle" ought to be used throughout the body of the article, with a short section on controversy added to explain that Helen Caldicott, a notable opponent of civilian nuclear power, prefers the term "fuel chain". Perhaps this is naive, but I expect that she'd even be willing to publish something short but citation-worthy if a third party simply e-mailed her and explained it was needed in order to include discussion of the controversy in a Wikipedia article. I would do all of these things and the edit myself, but I'm too new to the Wikipedia to delve into controversy. Thanks Ahnrenene (talk) 05:34, 22 December 2012 (UTC)
- Treating it as a controversy might make sense, but soliciting a posting from Caldicott doesn't seem kosher. I think we'd want a secondary source describing the nature of the argument over terminology. But I'm not sure how much of a controversy there is, since this discussion is the first mention I've seen of the issue. NPguy (talk) 16:18, 22 December 2012 (UTC)
- Actually, I don't know why I didn't think of this last night, but it occurred to me that Mycle Schneider or Yves Marignac (both notable nuclear gadflies) would probably have some stern words about the appropriateness of the word "cycle" as applied to direct disposal. Sure enough, a 2008 research report on France published by the International Panel on Fissile Materials deliberately calls direct disposal a "fuel chain" on pages 2 and 15. Incidentally, the report was authored by both Schneider and Marignac. I think this is probably enough to warrant the inclusion of a controversy section as previously described. In spite of this (or perhaps because of this), I would still advocate removal of the term "fuel chain" from the article's introduction. It does not strike me as very encyclopedic to state as truth something that one group simply wishes were reality. Ahnrenene (talk) 22:00, 22 December 2012 (UTC)
Support the images by quantities
In the section http://en.wikipedia.org/wiki/Nuclear_fuel_cycle#Front_end , there's a very nice series of images from the ore, over the cake all the way up to the last part of the chain: the nuclear fission material - eventually the enrichment part could be added with pics, but can we please get the numbers on it?
To get 1 ton of fission material, how many tons of cake and ore does this relate to?
If not here, where should readers be able to find it?
- Are you asking what the atomic abundance of 235U is in natural uranium? If so, the answer is ~.72% 235U and ~99.28% 238U (I think 236U is negligible). You can find a discussion of this in Shultis & Faw 2002. So, ore is harder to talk about because there are so many of them, but yellowcake is basically all U3O8 where the uranium matches the natural isotopic abundances. PWR fuel is UOX, or UO2, with 3% - 5% enrichment. For the sake of calculation, let's assume you want to know how many grams of fuel f at x% enrichment corresponds to y grams of yellowcake. The mass of UOX per mole is (267 g/mol)(x/100) + (270 g/mol)((100-x)/x). Because there are 100 total moles of U in UOX per x moles of 235U at x% enrichment, the mass of fuel f per mole of 235U is 267 g/mol + ((100-x)/x)270 g/mol. So, we need only determine the number of moles of 235U in y grams of yellowcake. The mass per mole of yellowcake is about 842 g/mol (that is, mostly 238U, so 238*3 + 16*8). There are 3 moles of U per mole of yellowcake, and .72 moles of 235U per 100 total moles of natural uranium. So the number of moles of 235U in y grams of yellowcake is (y grams)(1/842 mol/g)(3/1 mol U/mol yellowcake)(.72/100 mol 235U/mol U). Putting it altogether, f = -7.696e-5*(x - 9000)*y/x. Thus, you need over 7.22 tons of yellowcake to get 1 ton of 5% enriched fuel, or over 4.33 tons of yellowcake to get 1 ton of 3% enriched fuel. Of course, effluents from enrichment still have some 235U, so the yellowcake requirement is higher in reality. Could this calculation simply be included on the page? Ahnrenene (talk) 22:00, 22 December 2012 (UTC)
- Great explanation. Of course, this is an encyclopedia. In fact you can integrate it in the article only if you find the calculation somewhere in a document published by a notable person. Maybe it can be as simple as you publishing it on a blog, explaining that you are a notable figure and then referencing to yourself. --SvenAERTS (talk) 16:02, 19 January 2013 (UTC)
- Secondly, I was also referring to the amount of ore that needs to be excavated. I understand there can be differences from site and origine. But can't we bite the bullet and get at least some indicative quantities? It will also be useful for contributors with knowledge about the other materials in the ore and the issues related to keeping that part safe as well. --SvenAERTS (talk) 16:02, 19 January 2013 (UTC)
- I think the idea is to give rough quantitative information on how much material is present at each stage in fueling a nuclear reactor, e.g. X tons of ore needed to produce Y tons of yellowcake and Z tons of LEU fuel in order to fuel a 1000 MWt reactor for one year. You would need to consider the enrichment tails assay, which typically ranges between 0.2% and 0.4% U-235. Each would be a range, particularly the first one as it depends on widely varying concentrations of uranium in ore. Other factors include the enrichment level of the fuel and the burnup achieved in the reactor. NPguy (talk) 19:26, 23 December 2012 (UTC)
No mention of Russia or France
I don't understand why there's no mention of Russia or France in this article. France is considered an exemplar of the closed fuel cycle model, right? And Russia has the only operating commercial fast neutron reactor in the world (BN-600), right? Anyway, there are few enough nuclear nations that I think the article could stand to mention every single one without loss of scope or dilution of notability. If folks don't object, I'll make the additions. Ahnrenene (talk) 05:46, 22 December 2012 (UTC)
- I assume your intention is to intersperse such references throughout the article, rather than add sections on national fuel cycle approaches. This makes sense. France is already (indirectly) mentioned under "Europe." I would suggest a section on international reprocessing services, pointing out that Russia, France and the UK offer such services, on different bases. France and the UK require the return of high-level waste to the country of origin. France will also fabricate the plutonium into MOX and return to the country of origin, a business the UK tried but failed at. Russia will take back and reprocess spent fuel that it supplies and keep the plutonium and waste. NPguy (talk) 16:35, 22 December 2012 (UTC)
Two topics that might deserve greater attention are the breeder fuel cycle and international approaches to the fuel cycle.
Many countries originally saw -- and a few still see -- breeding as the ultimate goal. In principle, it can make more complete use of uranium (or thorium) fuel, and significantly reduce waste. Thermal recycling (in light water reactors) of plutonium as MOX fuel was generally seen as a small step in that direction, since it does relatively little to achieve those benefits. The most that would be needed here is a brief summary linking to the main article Breeder reactor.
Since the early days of the atomic age (the Acheson-Lilienthal report and Baruch Plan) people have proposed international approaches to the fuel cycle as a way of limiting the risk of spreading sensitive nuclear fuel cycle technologies (enrichment and reprocessing) that could be used to produce fissile material for weapons. I don't think there is an article that covers this topic. NPguy (talk) 16:55, 22 December 2012 (UTC)