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Centrifuge May Be Superseded by Laser Enrichment 346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Centrifuge May Be Superseded by Laser Enrichment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 itsdapead (734413) on Monday May 29, 2006 @06:40AM (#15423906)
    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?

    Objective answers - rather than pro-nukular or anti-nuclear spin - preferred (some hope!)

    • 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]
      • Objective answers - rather than pro-nukular or anti-nuclear spin - preferred (some hope!)
        That site linked to is titled "Nuclear Energy institute" and has such topics as "Nuclear, the clean air energy". Not that I don't agree with them that nuclear power is a very good idea, but seriously, they do have a bit of a political slant don't they?
    • MOX Anyone? (Score:4, Insightful)

      by turgid (580780) on Monday May 29, 2006 @07:08AM (#15423966) Journal

      The first generation of nuclear reactors in the UK (Magnox) used natural (i.e. unenriched) uranium metal as fuel.

      This meant that the fuel was very cheap to make but the fuel cans had to have a low neutron capture cross-section, hence the Magnox. This limited the temperatures at which the reactors could operate.

      Moving to enriched uranium allowed the use of stainless steel cladding which keeps its integrity to much higher temperatures and is mechanically stronger.

      There have been many developments in nuclear fuel technology since the 1950s, as one might expect. MOX was a good idea, but derailed by BNFL corporate incompetence and "environmentalist" hysteria.

      The idea with MOX is that, instead of enriching uranium to increase the proportion of fissile U-235, you mix in fissile plutonium recovered from used nuclear fuel which is then "burnt up" in the new fuel to provide power. Plutonium isotopes are natural byproducts of the nuclear reactions in fission reactors.

      Perhaps it would be more economical and environmentally-friendly to use more MOX than enriching fresh uranium?

    • 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.
    • 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 o

  • by charlie (1328) <charlie@anti[ ]e.org ['pop' in gap]> 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].
    • So you're claiming they have been testing the technology for decades, very interesting. I'm sure they should update the article summary to reflect this.
    • Why Australia first, you say? Well, they've got all those sharks they're goin to need.
    • MOD PARENT UP!!! Excellent links.

      Quote from the first linked article: "In MLIS, an infrared laser is directed at uranium hexafluoride gas. The laser excites uranium 235 hexafluoride gas, while not disturbing the uranium 238 hexafluoride gas."

      In 1972 or 1973, I built an apparatus to test whether a flowing gas carbon monoxide laser could excite uranium 235 hexafluoride. My little project was shut down without explanation.

      The Silex web site [silex.com.au] gives almost no information. The "about Silex" [silex.com.au] web page missp
  • A question? (Score:5, Funny)

    by Anonymous Coward on Monday May 29, 2006 @06:45AM (#15423914)
    Do you know where I can find detailed information about that new method?

    Kisses,
    Ahmadinejad

    • Strangely, the article fails to mention that enriched uranium "can be used for nuclear weapons". It is almost as if the editors understood that reactor-grade uranium cannot be used for nuclear weapons, and therefore did not include this misleading phrase in the article.

      Which begs the question as to why they do it in every single story on that other nation's enrichment experiments.
  • Short on details? (Score:4, Insightful)

    by saforrest (184929) on Monday May 29, 2006 @06:53AM (#15423932) Homepage Journal
    If this is really so novel and useful, surely an analysis of it exists that is not written by the guy trying to sell it!

    The article goes on to explain that six other countries have tried laser-enrichment schemes and failed, but this effort has succeeded, and the only possible hint at why is that this new approach is that it is more "elegant and sophisticated".

    Even a link to the press release [world-nuclear.org] would have provided a bit more information (though more legalistic than technical).

  • Oh goody (Score:3, Interesting)

    by TopSpin (753) * on Monday May 29, 2006 @06:54AM (#15423935) Journal
    The post mentions diffusion and centripetal enrichment. There is actually a third method that has been used by several nations. The "calutron" separates isotopes using a magnetic field. It is the least efficient and most expensive method, so it is uncommon. However, it was used by the Manhattan Project and Saddam had an array running in Iraq at one time.

    Making Uranium enrichment easy is not necessary a good thing. Uranium ore isn't hard to get. Enriching it is the tough part. The same processes used to make fuel lead directly to gun-type "atom" bombs. It's just a matter of degree and some machining.

    Get this process down to something small enough to quietly function in a barn and you could build a weapon inside the borders of your target. A gold mine or somesuch would be all you need for cover.

    • Get this process down to something small enough to quietly function in a barn and you could build a weapon inside the borders of your target. A gold mine or somesuch would be all you need for cover.

      Your idea is crazy, but is it crazy enough to be...oh shit.

    • They reduced the power requirements in half.

      That's still a lot of power. Not something you'll do by plugging into a wall socket found in a barn.

      Oh, and then there's the matter of the radiation. The Boy Scout who enriched his own nuclear fuel stopped when the geiger counter on his dashboard freaked out when getting within a couple of blocks of his house.

      The enrichment process will still require a lot of heavy machinery, power, lasers, and shielding. Not something you can just "Throw up in a barn" somewhere.
  • Centrifuges (Score:3, Insightful)

    by BenBenBen (249969) on Monday May 29, 2006 @06:55AM (#15423937)
    The spinning method requires 'thousands and thousands of centrifuges'.
    Unless you're Iran, in which case only 50 centrifuges is enough to put you "a few months away" from a nuclear weapon, according to Olmert. Or, y'know, 10 years at best, according to the latest National Intelligence Estimate. Of course, powers within Iran that are more relevant than Ahmedinejad have declared that atomic weaponry is unislamic and issued a fatwa against gaining them, and Ahmedinejad isn't the head of the military anyway. But look! Over there! They're making Jews wear yellow ribbons! Quick, bomb them!

    Sigh.

    • Unless you're Iran, in which case only 50 centrifuges is enough to put you "a few months away" from a nuclear weapon, according to Olmert. Or, y'know, 10 years at best, according to the latest National Intelligence Estimate.

      I would be significantly more likely to trust the Israeli intelligence services than the American, particularly after the Iraq fiasco. I think it's generally accepted that Israel has one of if not the best intelligence services in the world.

      (Before anybody says it, I'm aware that th

      • Re:Centrifuges (Score:3, Interesting)

        by BenBenBen (249969)

        The manner in which Mossad tricked the US into attacking Libya was described in detail by former Mossad case worker Victor Ostrovsky in "The Other Side of Deception," the second of two revealing books he wrote after he left Israel's foreign intelligence service. The story began in February 1986, when Israel sent a team of navy commandos in miniature submarines into Tripoli to land and install a "Trojan," a six-foot-long communications device, in the top floor of a five-story apartment building. The device,

        • and Social Security, and Public education, and well, just about everything.
        • It's "drown it in a bathtub." :)

          Which is why it became a pretty good anti-Republican response, superimposed on images of Katrina-damaged areas.
        • Republicans (Score:4, Funny)

          by Mark_MF-WN (678030) on Monday May 29, 2006 @09:12AM (#15424259)
          It's not just republicans, it's all bad-government conservatives. What happened to the days when conservatives had the balls to just say "centralism sucks, so we're cancelling these programs and lowering taxs"? Nowadays, they fuck up otherwise successfull programs, DON'T lower taxes, create deficits spending money on things that don't work, and lie constantly. Modern conservatives can't even come up with good lies. At least guys like Nixon made it hard to be sure exactly what was going on. You knew he was full of shit, but what kind of shit? Bush just relies on the fact that most Americans are as almost gutless as he is, and are too cowardly to doubt anything. Or my own "leader", Stephen Harper, who tells lies that are contradicted (often within hours) by undeniable evidence. At least Paul Martin's lies left you confused and uncertain about reality... Harper's just embarass us all.
    • This is /., so I'm not surprised, but you've missed the context. The "thousands and thousands of centrifuges" are to enrich uranium for power generation, not for nuclear weapons. A single bomb requires on the order of 10kg of enriched uranium. A large power station requires on the order of 25,000kg p.a. (source [wikipedia.org]).
      • A single bomb required uranium enriched to around 85% u238, which takes a system of a thousand or more cascading centrifuges many, many weeks.

        Power plants require uranium to be enriched to around the 4% mark, which takes fewer centrifuges and less time - as someone more qualified than I said when Iran announced its enrichment achievements, "Iran Now Capable of Making Glow in the Dark Watch Hands"

        • Excuse me? Nuclear weapons use either U-235 or Pu-239, not U-238. If you try to use U-238, your bomb is not going to do a damn thing except create a loud bang with no other results when you set off the explosives.
    • Re:Centrifuges (Score:3, Insightful)

      by Firethorn (177587)
      Or you've been working on it for years. Sure, the USA might have thousands of centrifuges, but we also built thousands of nukes over the years. If it takes a 'thousand centrifuge years' to process enough for one nuke, then it'd take Iran 20 years to make one.

      Of course, the questions of efficiency, size of intended nuke, processing rate, how much people believe that Iran has 'only' 50 centrifuges(we've been wrong before!) have some importance as well.

      Oh, and it's not just the Jews that are to wear 'ribbons
      • Re:Centrifuges (Score:5, Insightful)

        by BenBenBen (249969) on Monday May 29, 2006 @07:23AM (#15423999)
        The clothing thing is a hoax, a lie, disinformation to be endlessly repeated, half-remembered and alluded to even long after it's been proven bogus.
      • Re:Centrifuges (Score:3, Interesting)

        by BenBenBen (249969)

        how much people believe that Iran has 'only' 50 centrifuges(we've been wrong before!)

        Umm, you mean about Iraq? You do realise that we were "wrong" on purpose, and totally the other way - mobile biological labs turned out to be weather balloon inflating equipment, fertilizer factories were labelled as anthrax factories and the weapons located "around baghdad and tikrit, north, east, west and south somewhat" (to quote Von Rumsfeld).. didn't exist.

        Plus, it would have been a lot easier to keep track of what equ

        • Re:Centrifuges (Score:3, Interesting)

          by Firethorn (177587)
          Umm, you mean about Iraq?
          I mean intelligence in general. Pretty much all intel groups make mistakes, and quite frequently. Maybe not as bad or willfully as Iraq, but it still occurs. It's like playing poker.

          Plus, it would have been a lot easier to keep track of what equipment Iran was buying if Dick Cheney hadn't knowingly outed a covert CIA agent tasked with Iranian counterproliferation as political retribution against her husband.

          True or false, I believe that it's more of a matter that even if it's dif
      • 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]
    • From Debka:

      "Russian experts completed the initial plans in 2003 and construction began in early 2004. In late 2005, Bulgarian transport planes delivered tens of thousands of centrifuges from Belarus and Ukraine; they were transported directly to Neyshabour. In January 2006, 23 Ukrainian engineers arrived to start installing the equipment, joined in February by 46 Belarusian nuclear experts who are working in shifts to prepare the 155,000 P-1 and P-2 centrifuges for operation.
      This compares with 60,000 in Nat
      • 40,000 are available for inspection by whom? The IAEA? They must have forgotten to mention them.

        Your quote makes zero sense - do you have any idea how much stabilised power you'd need to run 155,000 centrifuges for weeks? The IAEA (and the US) watches all ex-Soviet nuke equipment so closely you probably couldn't clean them without there being a note made in 15 different databases, but they managed to fly 155,000 centrifuges to Iran without anyone noticing?

        Your point appears to be that anyone can pull anythi

        • The IAEA to my knowledge are the only ones who do nuclear inspections and as far as I can tell they included the inspections of that facility in their public reports.

          I didn't quote anything about Iran moving anything without anyone noticing. Did you feel the need to just make that up?

          Anyway as I mentioned in my previous post I do not completely believe this data and do not encourage anyone else to (I have been unable to verify the quantities listed).

          So I gather you have no other point... outside of just be
          • My point was exactly that the IAEA haven't reported on 40,000 centrifuges - your quote said "open to inspection", I was wondering by whom.

            "In late 2005, Bulgarian transport planes delivered tens of thousands of centrifuges from Belarus and Ukraine; they were transported directly to Neyshabour." - sounds like moving stuff to me

            My point was that you are quick to quote what is obviously complete bullshit, and then say it makes you uneasy - even though, yes, you said it was unproven.

    • They're making Jews wear yellow ribbons!Quick, bomb them!



      I am not certain if this form of discrimination warrants an air strike, but certainly, it would make this the country that practices it a sort of Pariah in the minds of the civilized world.
  • 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.

    • Yeah, it's interesting that he's not even making particularly optimistic claims for the process. Goldsworthy says it "may halve enrichment costs", not cut the cost by a factor of ten or anything. Sounds to me like in all probability it will not actually be any cheaper than current methods once the reality-checking has been done and all costs associated with carrying out the process are factored in, especially after reading your description of what's likely involved.
    • 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.

      Yeah. Right there is where the difficulties with this method became most apparent to me. Any method that requires you to have a vaporised metal floating around is probably best left in the laboratory. Just look at all those Mad Hatters!
    • by Asphixiat (451920)
      ...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 fo
    • I like to call this the "Ninja Effect". Whenever anything is discussed online, a bunch of the participants will begin claiming to have various exotic credentials. The claim to being a ninja is a particularly notable example, as are other martial arts. Any type of scientist you can think of, there are a thirty guys in the conversation who are leading experts in the field. There are usually a few millionaire playboys who live in small towns and sleep with every woman in their area code. Oh, and nearly ev
    • 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.

      But the authors/editors of every single story on the Iranian enrichment program has felt it necessary and not misleading at all to employ the phrase, "enriched uranium, which can be used for nuclear weapons..." Don't you realize how important it is to keep this myt
      • You aren't some kind of terrorist sympathizer, are you?

        It's worse than that. He's (gasp) not funded by ad revenue.

        We have to silence him immediatly, or he may pose a threat to our essential entertainment industry.
      • 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.
    • 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 Phanatic1a (413374)
      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 b
    • This sort of informed response is why Slashdot's rating system needs to be revised to support scores of up to +10 informative on a logrithmic scale.

  • All they need to watch for is large aquariums for the sharks.
  • 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)
    • Re:Mass spectrometry (Score:4, Informative)

      by DerekLyons (302214) <(moc.liamg) (ta) (retawriaf)> 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.

  • by JumpingBull (551722) on Monday May 29, 2006 @08:24AM (#15424128)
    And you have the potential for electrolysis.
    Process heat comes from the Sun, still the best fusion reactor going.
    Electrolytic by-products are:
    • oxygen
    • silicon
    • a glassy slag concentrating mineral impurities to higher grade ore

    Now if the reaction can be combined with some hydrogen injection to make water and ease the total (electrical) energy required you get a nice sustainable technology. Water, also.

    Solar cells are made from the silicon, formed into parabolic mirrors that focus the IR band to the smelting pot. Interference coating the cells is easy with the free nothing called a vacuum

    Electricity from the power cells drives the electrolysis and runs the station power.

    With all that silicon, I'm betting that some composition can make silicon into something more ductile.
    Cheap building material would be nice...

  • 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
  • The sharks with frickin' lasers were dangerous enough. Now they're gonna be enriching uranium!

  • Two Words (Score:3, Interesting)

    by ShooterNeo (555040) on Monday May 29, 2006 @08:51AM (#15424190)
    Two Words : OH SHIT.

    I don't mean to be too alarmist, but this is VERY bad news. See, it's easy to get access to uranium ore. Many countries have the mineral, and buying yellowcake is not supposed to be all that hard. Heck, some of it supposedly went through Africa. If you have just a few kilograms of highly enriched uranium, again it is easy to make a bomb. Spherical explosives aren't needed, a simple crashing together of a critical mass is enough. 10-20 kilotons is still enough to cut the heart out of a major world city, and kill hundreds of thousands of people.

    But getting from A->B WAS ludicriously expensive. I read that it takes a year for a sample to travel from one side of the centrifuge plant to another, and these plants have to be enormous, costing billions. The laser method as described appears to be much cheaper and generates probably close to 100% pure U-235. Yes, it is a secret technology, but the plans can be stolen or bought, and lasers and all the other stuff needed to make it work are not restricted exports.

    It might still cost a billion dollars to make a nuke, but that's it - not 10 billion. Most private individuals without access to nation state resources can't do it, but even the poorest dictatorship in the world can probably scrape together or steal from the U.N. a billion.
  • ...Methods of enrichment? Well, shit...I guess the Calutron [lbl.gov] [wikipedia.org] has to go back into the closet. Since it was used long before there were any reactors [angeltowns.net], and uses low tech methods, Iraq would never [nuclearweaponarchive.org] use one.
  • by Ancient_Hacker (751168) on Monday May 29, 2006 @09:16AM (#15424267)
    It's just swell to work in a lab, but you should occasionally read a newspaper or surf the internet.

    Right now, nobody needs or wants any more U235, except for North Korea, Iran, and various splinter groups.

    The US Govt has PILES of the stuff, as does the USSR. Plus many tons of Plutonium. All very expensive stuff, but worth less than zero.

    There's more tons of U235 and Plutonium in all the unprocessed fuel elements that have outlived their usefulness in nuclear reactors. The stuff is so worthless it's being stored or buried, not put through a relatively cheap chemical reprocessing cycle to recover the U235 and Plutonium.

    If we needed more U235, there are several multi-billion dollar separation plants in mothballs that one could restart with relatively little effort.

    So this laser-enrichment, IF it can ever be gotten working on a large scale, is (a) a threat if rogue states and the Mafia get into it and (b) Will produce soemthing nobody needs, and (c) probably riskier and more expensive than just starting up the old plants.

  • 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

    • The point here is however that the reducted mass of the u235+electrons system is not exactly the same than the one of the u238+electrons system. Therefore the absorption frequencies are slightly different, enabling the separation. That point about reducted mass is usually made in freshman physics courses but forgotten afterward, everyone happily taking the mass of the lighter object as the reducted mass and considering the heavier object at rest (even in the earth-moon system) when it actually revolves aro
  • Natural Uranium (Score:3, Interesting)

    by FrankDrebin (238464) on Monday May 29, 2006 @11:08AM (#15424614) Homepage

    TFA states "..[p]ower stations are fuelled by a specific blend of two types of uranium. About 5 per cent must be uranium 235...".

    This is of course untrue, for example the CANDU [wikipedia.org] reactor uses heavy water and natural uranium. Not processing uranium is cheaper than processing, laser or not.

  • IFR & CANDU (Score:3, Informative)

    by cdn-programmer (468978) <terr@terral[ ]c.net ['ogi' in gap]> 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.

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