Centrifuge May Be Superseded by Laser Enrichment 346
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'."
Laser enrichment isn't new (Score:4, Informative)
Re:Laser enrichment isn't new (Score:1, Informative)
are perfecting the technology. General Electric are commercialising it.
Re:hot potato. literally. (Score:3, Informative)
I think the solution is to put butt-loads of funding into bringing fuel cell technology to the forefront.
Re:True cost of nuclear...? (Score:5, Informative)
http://www.nei.org/index.asp?catnum=2&catid=260 [nei.org]
This is hardly a new technology (Score:5, Informative)
http://en.wikipedia.org/wiki/Mordechai_Vanunu [wikipedia.org]
So - nothing new here, move along, move along.
Women And Warheads (Score:5, Informative)
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)
Ya, it does sound familiar... [yahoo.com]
Mass spectrometry (Score:4, Informative)
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:Women And Warheads (Score:3, Informative)
Two methods? (Score:3, Informative)
> 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
Re:True cost of nuclear...? (Score:2, Informative)
Just to nitpick, it's a kWh, not kW/h. That would make it a Joule/second/hour.
This is Not "nuclear power," this is AUS Nuclear (Score:3, Informative)
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)
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.
Re:Women And Warheads (Score:3, Informative)
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)
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)
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
Re:Women And Warheads - extreme temperature (Score:2, Informative)
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.
Re:Women And Warheads - extreme temperature (Score:4, Informative)
Re:Women And Warheads (Score:3, Informative)
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.
Re:Women And Warheads (Score:3, Informative)
Re:Centrifuges (Score:3, Informative)
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/4981
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.
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=/n
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)
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)
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)
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)
> 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!"
Re:This is Not "nuclear power," this is AUS Nuclea (Score:2, Informative)
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.