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Centrifuge May Be Superseded by Laser Enrichment 346

Posted by Zonk
from the poom-poom-bang-kapow-lasers dept.
An anonymous reader writes "Australian scientists have discovered, after a decade of tests, a new way to enrich uranium for use in power plants." From the article: "There are at present only two methods for sifting uranium atoms, or isotopes, to create the right mix. One, called diffusion, involves forcing uranium through filters. Being lighter, U-235 passes through more easily and is thus separated from its heavier counterpart. The second method, widely adopted in the 1970s, uses centrifuges to spin the heavier and lighter atoms apart. Both, said Dr Goldsworthy, are 'very crude. You have to repeat the process over and over,' consuming enormous amounts of electricity. The spinning method requires 'thousands and thousands of centrifuges'."
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Centrifuge May Be Superseded by Laser Enrichment

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  • by charlie (1328) <charlie&antipope,org> on Monday May 29, 2006 @06:43AM (#15423909) Homepage Journal
    It's been around for over 20 years [thebulletin.org]. What's new is that the Aussies appear to be commercialising it [uic.com.au].
  • by Anonymous Coward on Monday May 29, 2006 @06:45AM (#15423916)
    Wrong. It has been around, but has not been competitive with centrifuges. Aussies
    are perfecting the technology. General Electric are commercialising it.
  • by Enderandrew (866215) <enderandrew@ g m a i l . com> on Monday May 29, 2006 @06:47AM (#15423923) Homepage Journal
    Bingo. One can make a strong arguement for nuclear power. It is efficient and clean. Yet we don't seem to want to let anyone have it because it might be a cover for nuclear weapons. What to do?

    I think the solution is to put butt-loads of funding into bringing fuel cell technology to the forefront.
  • by DemoLiter3 (704469) on Monday May 29, 2006 @07:04AM (#15423954) Homepage
    No problem : here you have an emissions comparison for all widespread methods and various pollutants

    http://www.nei.org/index.asp?catnum=2&catid=260 [nei.org]
  • by Trestop (571707) on Monday May 29, 2006 @08:03AM (#15424068) Homepage Journal
    According to Mordechai Vanunu, the Israeli nuclear whistle blower - as quoted by the Sunday Times - Israel had laser enrichment technology, in actual production use, at the early 1980s.
    http://en.wikipedia.org/wiki/Mordechai_Vanunu [wikipedia.org]

    So - nothing new here, move along, move along.
  • Women And Warheads (Score:5, Informative)

    by cybrpnk2 (579066) on Monday May 29, 2006 @08:03AM (#15424069) Homepage
    I'm one of the "500 scientists" who worked on the ""failed" US efforts in the early 1980s, and I'd take this whole report with a grain of salt. First of all, just how far the US got with our effort is classified and having the media calling it a "failure" doesn't mean that we never accomplished in our labs 20 years ago what these Austrians did in theirs last month. The US lab effort was HUGE and not just aimed at uranium enrichment. There was a seperate program for seperating plutonium isotopes via laser enrichment to fine-tune and further miniturize nuclear weapons to an amazingly small package. These were the Reagan Star Wars years, after all.

    However, it's a LONG way from lab benchtop enrichment experiments to a functioning enrichment plant. And once you get to that functioning enrichment plant, there's the question of whether or not it was economically justifiable to build in the first place. This is where the American effort "failed" - even on paper, it never made sense to pursue this technology because it was just too expensive. Sure, you need thousands of high-precision centrifuges to run an enrichment cascade. This was still cheaper than building a laser enrichment plant.

    The designs for a uranium laser enrichment plant ON AN INDUSTRIAL SCALE are not for the fainthearted. YOu've got to have the uranium in a gaseous state. That means heating it so hot that not only do you have a pool of molten uranium, but it's BOILING. The laser is going through the HOT uranium "steam". The only material that can stand up to these temperatures is pure graphite. The design becomes like a series of rain gutters on a house that carries "more enriched" and "less enriched" streams of molten uranium back for reboiling. Somehow you've got to figure out a way of putting optical ports into this hellhole to fire the laser beams in. The laser beams themselves are a weird wavelength (green) and takes some really expensive gear to generate at all, much less with intense enough power to penetrate deeply into a fog of molten uranium. Doing all of this cheaply? Good luck.

    And in the background overshadowing enrichment plant economics was and is the fact that nuclear power plants are still just too expensive a way to generate electricity (primarily due to regulatory costs) compared to coal and natural gas turbine plants. The expected boom in nuclear power plant construction forcast in the 1970s and early 1980s never materialized, mainly due to Thre Mile Island and Chernobyl, and so the need for new-fangled enrichment technology as a support industry never materialized with it either.

    Right now the cheapest way to come up with fuel for a nuclear power plant is not laser enrichment or even centrifuge enrichment. It's diluting old Russian warheads [usec.com], all 30,000 of them, down from 93% enriched uranium back to 3% uranium. This, along with all those Russian brides [russianbrides.com] American men now have access to, are the REAL spoils of winning the Cold War.

  • Re:Centrifuges (Score:4, Informative)

    by Adult film producer (866485) <van@i2pmail.org> on Monday May 29, 2006 @08:04AM (#15424070)
    "Oh, and it's not just the Jews that are to wear 'ribbons', it's chritians as well. Patch sewn onto clothing. Sounds familiar, doesn't it?"

    Ya, it does sound familiar... [yahoo.com]
  • Mass spectrometry (Score:4, Informative)

    by nickovs (115935) on Monday May 29, 2006 @08:10AM (#15424086)
    There are at present only two methods for sifting uranium atoms, or isotopes, to create the right mix.

    There is a third method that has been used on an industrial scale, which is to essentially build a huge mass spectrometer. Mass spectrometers are usually used to separate atoms into their isotopes for analysis but Ernest O. Lawrence [atomicarchive.com] proposed this for the Manhattan Project [atomicarchive.com] and the Y-12 separator at Oak Ridge, TN, built in 1941 [atomicarchive.com], yielded some useful results before being superseded by gaseous diffusion at the K-25 facility and later the S-50 thermal diffusion plant. Indeed the first 200 grams of fissile material delivered to Los Alamos came from the electromagnetic separator, more than a year before the diffusion separator started operation (the uranium bomb dropped on Hiroshima used about 64Kg)
  • by cybrpnk2 (579066) on Monday May 29, 2006 @08:21AM (#15424117) Homepage
    Oops. My bad.
  • Two methods? (Score:3, Informative)

    by sphealey (2855) on Monday May 29, 2006 @08:28AM (#15424135)
    > There are at present only two methods for sifting
    > uranium atoms, or isotopes, to create the right mix.

    AVLIS has been around since the 1970s, and there is also the South African cyclonic process. There are also hints in the public literature that there are other methods that were examined by the Manhatten Project and not pursued for various reasons.

    sPh
  • by Jedi Alec (258881) on Monday May 29, 2006 @08:47AM (#15424177)
    So does anybody have a figure for how much energy is used, how much CO2 is produced and how much other waste is produced in order to generate a kW/h of nuclear power?

    Just to nitpick, it's a kWh, not kW/h. That would make it a Joule/second/hour.
  • by Vexar (664860) on Monday May 29, 2006 @08:56AM (#15424208) Homepage Journal
    Okay, TFA is talking about Uranium 235, which is a weapons-grade isotope of Uranium, because it is fissile. Furthermore, this is necessary only because Australia uses Light Water Reactors. Fast Neutron Reactors and several other of the dozens of reactor designs do not need enrichment and work just fine off the naturally occurring U238.

    If you read up on the Gen-4 reactor designs, you'll find that greenhouse gasses, non-proliferation, safety, and more efficient designs (a LWR reactor is rather wasteful on the scale of designs) have been taken into consideration. Rest assured that the new reactors being built in Florida, and all across the USA are being built with the best, safest technologies available.

    Oh, and the thousands of centrifuges? That's just bad journalism. I don't know how lasers are cheaper at all (someone needs to actually write a decent article here), but for what it is worth, Nuclear Energy in the United States is cheaper than coal, but just barely.

    Check out www.nukeworker.com and ask your questions there. Those guys know their Uranium from their belly buttons!

  • Re:MOX Anyone? (Score:4, Informative)

    by turgid (580780) on Monday May 29, 2006 @08:57AM (#15424210) Journal

    As far as I'm aware, fissile plutonium doesn't always come out of the process - it needs to be a specific type of reactor, with enriched fuel, to "breed" plutonium...

    That's not true. In conventional nuclear reactors, the plutonium naturally produced is fissile, or at least a substantial proportion of it is. This gives rise to the "moderator coefficient of reactivity" in thermal reactors where an increase in moderator temperature brings about a proportional increase in the number of neutrons with the correct energy spectrum to cause fission in the plutonium. This is a form of neutron resonance.

    This is why Magnox and AGR reactors are "positive feedback" systems.

    When a Magnox reactor is new, there is no plutonium, so there is no plutonium fission, so for the first few months of operation, the reactor is negative feedback.

    In AGRs, the moderator temperature is kept constant by running the cold coolant gas through the moderator prior to cooling the fuel, so AGRs are negative feedback (and hence stable) as long as the moderator temperature is kept constant, which is achieved by active safety systems.

    PWRs, on the other hand, are light-water moderated. They are effectively under-moderated and are epi-thermal reactors. They are negative-feedback since any increase in the moderator temperature (water) causes it to expand, reducing its density and hence the amount of moderation. As long as you can keep pressurised water flowing around a PWR it is stable.

    In a previous life I worked in Reactor Physics at a nuclear power station.

  • by Asphixiat (451920) on Monday May 29, 2006 @09:01AM (#15424225)
    ...what these Austrians...

    There were Austrians in Australia working on enrichment? This is a very big deal politically here atm (in Australia that is you 'merican speed reader :)

    Australia is a nuclear free country (except for the Lucas heights reactor in Sydney, we make isotopes for medical research only). We flirted with it in the 50's, but we have, until recently been a country who feels we can sell uranium (we have a lot btw - like a whole lot) overseas, pretty much raw, and use almost none of it for our own purposes.

    Our Prime Minister has decided to ignite a nuclear debate. It will distract us from the real debate we should be having (about the new IR laws), and will to be fair, is probably better in the short term then carbon sequestration.

    A report was also delivered to the cabinet today, explaining that we (the tax payer) would pay a lot of money on insurance if we build the world's 5th Westinghouse AP1000 reactor in 10 years, or wait 10 years, and build the worlds 10th Westinghouse AP1000, and save a lot of cash. Howards other idea is to enrich the unranium, give it to countries on condition that they use it peacefully, and return it to us for storage and for us to store it safely, at their expense of course.

    As I said - lots of news down here, however, even the experts think right now it is probably too expensive, and the problem of which state will have the reactor, do the enrichment, or store the waste will make every body in our wide brown land bicker and argue for quite a while. This press release is probably part of the spin to deflect debate on our new IR (industrial relations) laws.
  • Re:Centrifuges (Score:1, Informative)

    by Anonymous Coward on Monday May 29, 2006 @09:16AM (#15424265)
    Yes, fertilizer factories that ground fertilizer into such fine particles that the fertilizer was utterly useless for actually growing crops, because it was fine it blew away. When the problem was complained about, the recommendation was made to put the fertilizer into the irrigation systems -- whereupon it clogged the systems and broke them.

    So, Iraq had fertilizer factores that produced utterly worthless, unusable fertilizer. Why would Iraq do that? Well, maybe they were just incompetent idiots who bought fine milling machines without understanding they'd be worse than useless for fertilizer.

    On the other hand, the fine milling gear was in fact exactly the stuff one would use to weaponize anthrax. If you hid the gear in bunkers, it would be awfully hard to explain it to weapons inspectors. But if you put the gear in a fertilizer factory and showed it grinding fertilizer, your anthrax-weaponizing facilities would be in plain sight of everyone. The ignorant, obtuse, and wilfully blind would say you didn't have any, even though it was in plain sight. And when the countries that held your country's debt and who wanted oil field contracts finally managed to get sanctions lifted from you, you'd have the gear already in-hand to resume production.

    Similarly, you could order aluminum tUbes for rockets to ever-finer specifications. Of course you'd go ahead and use them for rockets; that way you'd have an easy explanation for why you were ordering them. Sure, some people might notice that you were demanding far higher-quality than the rockets needed, and that they (unlike ordinary ones) would be suitable for use in a nuclear-productiuon facility. But you had a perfectly innocent explanation for the use of the tubes, and you'd have the tubes already in hand when the time was ripe to restart uranium enrichment. And the ignorant, obtuse, and wilfully blind could say you were just buying rocket tubes.

    And so on. It's amazing how much of a WMD program can be concealed by simply slapping an alternate label on the components and relying on the ignorant, obtuse, and wilfully blind to accept the nonsensical explanation for your posession of the components.
  • Fun with lasers (Score:5, Informative)

    by Deadstick (535032) on Monday May 29, 2006 @10:18AM (#15424468)
    That trick of selective absorption of laser light has some pretty neat applications...you can actually cool a gas by shining a laser into it.

    If a photon of precisely the right frequency (and therefore energy) hits an atom, two things happen:

    (1) It gets absorbed, and transfers its momentum to the atom -- i.e., gives it a little push.

    (2) One electron in the atom absorbs the photon's energy, exciting it to a higher energy level.

    Then, after a random time interval, two more things happen:

    (3) The electron drops back down to its old energy level.

    (4) The atom emits a photon, carrying the energy given up by the electron, and the photon's momentum delivers another push to the atom.

    But while the first push was in the direction of the laser beam, the second one is in a random direction -- so the affected atoms, statistically speaking, wind up with a net gain of momentum in the direction of the laser beam.

    So far, the laser is basically just stirring the gas. Now you tune the frequency of the laser a little bit lower. The "average" atom sees the photons at the wrong frequency, and the photons just truck on by. But atoms that happen to be moving toward the laser see the photons Doppler-shifted up to just the right frequency and they receive a push away from it -- so their average speed is reduced. Ba-bing, ba-boom, the gas is colder.

    Laser cooling, along with a couple of other techniques, made it possible to get the super-low temperature needed to isolate the Bose-Einstein Condensate which got the 2001 Nobel.

    rj

  • by ledvinap (412654) on Monday May 29, 2006 @10:18AM (#15424471)
    Uranium hexafluoride can be (and is) used in enrichment process:
    http://en.wikipedia.org/wiki/Uranium_hexafluoride [wikipedia.org]

    This substance is gaseous at 64C, no extreme temperature is needed. Laser enrichment works with this compound.

  • by cybrpnk2 (579066) on Monday May 29, 2006 @10:36AM (#15424519) Homepage
    Use of UF6 is the MLIS process, championed by Los Alamos. Use of atomic vapor is the AVLIS process, championed by Livermore. You would not believe the endless arguments that ensued during the 1980s over which was better. AVLIS won.
  • by Phanatic1a (413374) on Monday May 29, 2006 @10:51AM (#15424561)
    Boiling uranium?

    Huh? All the uranium centrifuge operations I'm familiar with use uranium hexafluoride gas. You dissolve the actual uranium in nitric acid, generating uranyl nitrate in solution. You extract the nitrate from the solvent, treat it with ammonia, reduce it to uranium dioxide with hydrogen, treat it again with hydrofluoric acid (UF4 now) and and oxidize it with fluorine gas to produce UF6, which is a gas at much, much lower temperatures and pressures than pure uranium.

    Why on earth would you boil the stuff? You've have to keep it hot in the centrifuges.
  • by Daniel Dvorkin (106857) * on Monday May 29, 2006 @11:32AM (#15424706) Homepage Journal
    Australians are white Christians. Iranians are brown Muslims. Therefore, Australian enriched uranium can only be used peacefully for nuclear power generation, while Iranian enriched uranium can only be used in nuclear weapons for terrorists. Hope this clears things up.
  • Re:Centrifuges (Score:3, Informative)

    by Ex-MislTech (557759) on Monday May 29, 2006 @02:12PM (#15425304)
    It's equally amazing the mental gymnastics some will go through to avoid facing the fact

    Deception and Agendas are aplenty, and we will not know whether or not you are right
    for some time, but...consider Iran's step to withdraw from the non-proliferation treaty.

    http://news.bbc.co.uk/1/hi/world/middle_east/49819 40.stm [bbc.co.uk]

    If you want to send a message that you are totally above board you would NOT subvert
    inspections by nearly 100% EU inspection teams, Iraq did this as well.

    Playing shell games, delaying inspectors from the EU, and declaring numerous massive
    presidential palaces off limits. Having huge stockpiles of "pesticides" that fit
    dual use in ammo dumps and bunkers with aerial camouflage .

    http://www.frontpagemag.com/Articles/ReadArticle.a sp?ID=13168 [frontpagemag.com]

    Former Iraqi officers speaking of the chemical weapons, and their coverup over
    intercepted phone calls in Iraq prior to the 2nd gulf war .

    http://www.slate.com/id/2078196/ [slate.com]

    17 UN resolutions that were ignored time an time again .

    The shell game, deceptions, and intimidation used against the inspectors and
    lack of "Full Inspections".

    http://www.telegraph.co.uk/news/main.jhtml?xml=/ne ws/2002/09/08/wirq208.xml [telegraph.co.uk]

    http://www.pm.gov.uk/output/Page277.asp [pm.gov.uk]

    If Iraq and Saddam were innocent , why then the elaborate deceptions,
    intimidation, hauling top soil away...

    To me ...

    It's equally amazing the mental gymnastics some will go through to avoid facing the fact

    Ex-MislTech

  • non-problem? (Score:2, Informative)

    by bagsc (254194) on Monday May 29, 2006 @02:22PM (#15425336) Journal
    You state that there is an excess of uranium. Is that why uranium prices have increased over 500% [azcentral.com] in the last six years? Commodity prices in general have been soaring, and many other countries use uranium. Electrification of India (nuclea power) and China (also nuclear power) is creating a surge in power consumption.

    The Soviet materials have been mostly reprocessed. Consumption has reached 80 thousand tonnes per year, and production is still less than 50 thousand tonnes. Additionally, GE has already signed to build a facility in the US. Obviously someone thinks it's worth the investment.
  • IFR & CANDU (Score:3, Informative)

    by cdn-programmer (468978) <.terr. .at. .terralogic.net.> on Monday May 29, 2006 @04:16PM (#15425693)
    There would be no reason whatsoever to enrich uranium (Other than to make bombs to kill people) if we were to use the CANDU and IFR technology.

    Fuel reprocessing however is necessary.

    There is just no way we can supply our energy needs in the long haul other than with nuclear... that is unless we accept a massive change in our life styles!

    Oil is peaking now. The actual month may well be in 2007 or even beyond that - but we are effectively already at peak because we cannot signficantly grow our supplies. We can increase our coal consumption and we can liquify it as well. We can also make bio-fuels. But they will not fill the gap created as conventional oil depleats. The short of biomass->ethanol for instance is that a tonne of any biomass (not the refined cooking oils!) is equivalent to about 2 barrels of oil. This is easy to illustrate by looking at the chemisty (CH2O)n -> C(n)H(2n+2).

    We are starting to face a major energy crisis and this is only the beginning - barely the tip of the iceberg.

    The issue is the current generation of reactors generate a pile of plutonium. While it isn't weapons grade Pu (too much Pu240 relative to the Pu239) it is still dangerous. The best course of action is to burn it up for power.

    The CANDU is a near breader design and is quite efficient in its use of neutrons. It is a decent reactor to use until IFR can be put into production. Note that a CANDU can easily burn the spent uranium fuel which is incorrectly called "waste". An IFR can even burn depleated uranium.

    Of course we need to allow fuel reprocessing for this to happen. The only reason we don't do it now is political. (for the short term... IFR combines the reprocessing on site and hense is far more secure).

    As for the cost of nuclear energy?

    The short answer is that enough governmental beauracracy can make _ANY_ industry unprofitable.
  • Re:Mass spectrometry (Score:4, Informative)

    by DerekLyons (302214) <fairwater@NOSPAM.gmail.com> on Monday May 29, 2006 @04:56PM (#15425798) Homepage
    There are at present only two methods for sifting uranium atoms, or isotopes, to create the right mix.

    [TFA refers to the two most common methods; gaseous diffusion and centrifuges.]

    There is a third method that has been used on an industrial scale, which is to essentially build a huge mass spectrometer.

    There's also a fourth method - thermal diffusion. In this method you have two concentric pipes, you run coolant through the inner pipe, and heat the outside of the outer pipe, and pipe uranium hexaflouride gas between them. This method was used by the Manhattan Engineering District[1] and was studied by the Japanese (during WWII) as part of their (miniscule) weapons program. The only good thing about thermal diffusion is that it's only slightly less murderously inefficient than electromagnetic seperation. (the 'giant mass spectrometers' of the OP, properly called 'Calutrons'.)

    Thermal diffusion was only pursued because the Navy had a boiler test and development facility that could provide the massive volume of steam needed as a heat source. It's small capacity limited it's role to providing enriched 'hex' to the Calutrons. (Using a more enriched feedstock moved them from hideously murderously inefficient to merely murderously inefficient.) Like the calutrons, the thermal diffusion plant was dismantled as soon as enough capacity from the gaseous diffusion (K-25) plant was available.

    Richard Rhode's The making of the Atomic Bomb discusses the various enrichment methods available in WWII in great detail.

  • Re:Centrifuges (Score:3, Informative)

    by Dire Bonobo (812883) on Monday May 29, 2006 @05:47PM (#15425949)
    > Former Iraqi officers speaking of the chemical weapons, and
    > their coverup over intercepted phone calls in Iraq prior to
    > the 2nd gulf war.

    You might want to read the followup piece [slate.com] by the same author. Not to spoil the surprise, but the heading is "How Colin Powell Got So Much Wrong About Iraq".


    Your evidence---all of it---is either old and discredited (like the above) or old and irrelevant (like the claim that presidential palaces were off-limits to inspectors, which was not true [cnn.com] about the pre-war inspections). What you're doing isn't mental gymnastics; it's mental sticking your fingers in your ears and shouting "Lalala I can't hear you!1!"

  • by Vexar (664860) on Monday May 29, 2006 @10:20PM (#15426592) Homepage Journal
    Okay, I admit that is funny, but do you know how much government-mandated medical testing goes on with these guys? They can't get near a reactor if they have had too much radiation exposure. Oh, and for even more information, the typical exposure received by people within 10 miles of the Three-Mile Island event was equivalent to the radiation exposure received during a round-trip transatlantic flight from the US to Europe. What does that tell you? The average flight attendant or pilot receives many times more radiation exposure than a nuclear power worker.

    If you think I'm making it up, do the research. The amount of Hollywood misinformation that the average person has is obscene. Here's one: you can't blow up a nuclear power plant and get an atomic explosion. What? Yeah, it's basically just glowing green rocks, water, pipes, dynamos, and a lot of concrete. You can blow up a natural gas or oil power plant, however.

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