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Thorium: The Wonder Fuel That Wasn't 204
Lasrick (2629253) writes "Bob Alvarez has a terrific article on the history and realities of thorium as an energy fuel: For 50 years the US has tried to develop thorium as an energy source for nuclear reactors, and that effort has mostly failed. Besides the extraordinary costs involved, In the process of pursuing thorium-based reactors a fair amount of uranium 233 has been created, and 96 kilograms of the stuff (enough to fuel 12 nuclear weapons) is now missing from the US national inventory. On top of that, the federal government is attempting to force Nevada into accepting a bunch of the uranium 233, as is, for disposal in a landfill (the Nevada Nuclear Security Site). 'Because such disposal would violate the agency's formal safeguards and radioactive waste disposal requirements, the Energy Department changed those rules, which it can do without public notification or comment. Never before has the agency or its predecessors taken steps to deliberately dump a large amount of highly concentrated fissile material in a landfill, an action that violates international standards and norms.'"
Is this about Thorium or Uranium 233? (Score:5, Interesting)
Interesting caption to use as the summary.
Re:Is this about Thorium or Uranium 233? (Score:5, Informative)
Thorium 232 + a neutron -> Uranium 233.
Note that the "United States produced, over the course of the Cold War, approximately 2 metric tons of uranium-233, in varying levels of chemical and isotopic purity" (from Wikipedia [wikipedia.org]. As best as I can tell from the BAS article, the missing U-233 is from "the Oak Ridge National Laboratory, the Rocky Flats nuclear weapons facility, and the Idaho National Laboratory" - i.e., it was weapons production related U-233, not stuff from a thorium breeder program, and probably a problem of bad book-keeping, not an actual loss of material.
Note that U233 is going to be highly radioactive, due to unavoidable U232 impurities, and will be such a strong emitter of gamma rays that this "makes manual handling in a glove box with only light shielding (as commonly done with plutonium) too hazardous." That, plus a failure to ever produce a non-fizzle U233 bomb, means that this really isn't a good fission bomb source material.
All in all, I actually expect better from the Bulletin of the Atomic Scientists.
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Re:Is this about Thorium or Uranium 233? (Score:5, Insightful)
Just about anyone can call themselves a scientist, or an advisor. I find it incredible the number of people still duped by those claims.
Indeed. Anyone that calls the NNSS a "landfill" and talks about "dumping" U233 there, is clearly trying to push an agenda, and is willing to mislead and distort facts in order to do so. That is not science.
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From the context, it sounds like he is referring to some officals attempting to dump U233 into a landfill even though it is a bad idea.
In the 1940s, nuclear waste was dumped into pits in Hanford, WA and we have spent tens of BILLIONS of dollars dealing with the cleanup, and future cleanup costs are projected to exceed $100 BILLION dollars. That is more than the annual cost of the Iraq ware at its peak. If you are seriously suggesting that some government bureaucrat was given permission to do that all over again, please provide a citation, and, no, the "Bulletin of the Atomic Scientists" is not a credible source. If the BAS said the the
Re:Is this about Thorium or Uranium 233? (Score:5, Insightful)
Thorium 232 + a neutron -> Uranium 233.
No entirely accurate.
Th232 + n -> Th233 -> U233 + e
You forgot to bombard the Th 233 with a positron going backward in time.
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Re:Is this about Thorium or Uranium 233? (Score:5, Funny)
They haven't yet, but they will eventually
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Pics or it won't happen.
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Damn it! I always forget the time traveling antiparticle! Is there nothing cooler in existence? Its like forgetting to get ice cream at the worlds greatest ice cream store.
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"For a terrorist, however, uranium 233 is a tempting theft target; it does not require advanced shaping and implosion technology to be fashioned into a workable nuclear device. The Energy Department recognizes this characteristic and requires any amount of more than two kilograms of uranium 233 to be maintained under its most stringent safeguards, to prevent “onsite assembly of an improvised nuclear device.” As for the claim that radiation levels from uranium 232 make uranium 233 proli
Re:Is this about Thorium or Uranium 233? (Score:5, Interesting)
Which is an interesting statement, given that the US government has never been able to successfully produce a working U233 bomb. In fact they've invested a lot of effort into Pu239 and U235, which would be pointless if all they had to do was bread common-as-muck (literally) Thorium into a useful nuclear weapons material for a fraction of the cost.
The reality is that U233 is almost entirely useless on it's own: off the top of my head you might be able to use it to make workable tampers for Plutonium implosion bombs; the evidence suggests that's actually the only place U233 has ever been used in a working weapon. That still wont get you far without the Pu and U235 (for the primary).
Re:Is this about Thorium or Uranium 233? (Score:5, Insightful)
No one is going to be manufacturing a traditional implosion style nuclear weapon out of Uranium-233 any time soon. However, a dirty bomb would contaminate a very large area with gamma emitting Uranium-232, causing quite a headache.
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causing quite a headache.
And tummy ache too. In fact, I bet the tummy ache comes first.
Re:Is this about Thorium or Uranium 233? (Score:5, Interesting)
Thorium 232 + a neutron -> Uranium 233.
Not exactly ;^)
Th232 + neutron -> Th233 (which isn't as stable stable)
Then two stages of beta- decay
Th233 -> Pa233 + electron + anti-neutrino
Pa233 -> U233 + electron + anti-neutrino
The problem is with U232 production is because all of these intermediate products are also fissile in the reactor (e.g., can interact w/ stray fast neutrons and undergo extra neutron decay before undergoing beta- decay resulting in U232 instead of U233).
However, the issue isn't that U232 is so unstable it decays with products that emit large amounts of gamma radiation (which in the decay chain, Tl208 is a big gamma emitter so it's really dangerous), it's mostly that you can't use chemistry to separate U232 from U233 (since only the mass is different, not the valence electrons). You either have to use advanced techniques (e.g, laser isotope separation), or modify your reactor parameters so that U232 production is reduced.
The ironic thing is that purported proliferation resistance of U233 is because reactors can be deliberately tweaked to increase the concentration of U232 to denature the U233. However, as I understand it, there is no particular technical reason to do this other than proliferation resistance (except to make it more dangerous to potential nuclear power plant workers as if that was a goal). If a rogue country wanted to operate a Th reactor to create large amounts of U233 w/o a limited amount U232 contamination, apparently it's not that hard to do (basically replacing the fuel more frequent schedule than normal, since most of the U232 yield comes at the end of the fuel cycle where there are more high energy neutrons bouncing around)...
That, plus a failure to ever produce a non-fizzle U233 bomb, means that this really isn't a good fission bomb source material.
If your goal is to simply produce a bomb, (not necessarily a large one with optimal yield), apparently India detonated an experimental U233 bomb as part of their Pokhran-II tests back in 1998... I don't think that bomb was a fizzle...
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Yeah, and check out the caliber of their Science and Security Board [thebulletin.org]. They've got the author of "The Physics of Star Trek"!
Seriously, James Hansen is on their board also, which is a bit of a surprise. He's staunchly pro-nuclear power
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Both.
Thorium-232 is not fissile, it cannot be used to drive a nuclear fuel cycle. However, Thorium-232 is fertile, it can be bred into an isotope that can drive a nuclear fuel cycle, which in this case is Uranium-233
questionable presentation (Score:5, Interesting)
Statement of ridiculousness include;
For a terrorist, however, uranium 233 is a tempting theft target; it does not require advanced shaping and implosion technology to be fashioned into a workable nuclear device. The Energy Department recognizes this characteristic and requires any amount of more than two kilograms of uranium 233 to be maintained under its most stringent safeguards, to prevent “onsite assembly of an improvised nuclear device.” As for the claim that radiation levels from uranium 232 make uranium 233 proliferation resistant, Oak Ridge researchers note that “if a diverter was motivated by foreign nationalistic purposes, personnel exposure would be of no concerns since exposure would not result in immediate death.”
But this material is actually extremely difficult to make a warhead out of or use in any weaponized manner other than a dirty bomb. But with little effort, its easy to find that U-233 has the "unavoidable co-presence of uranium-232[6] which can make uranium-233 very dangerous to work on and quite easy to detect." That was conveniently ignored.
So, while it could be used in a dirty bomb, there are much easier, more tempting targets for that. Particularly when its material stored in a highly protected area. "No concerns"? Give me a break.
As for the Nevada waste thing. What he describes as a simple "landfill" is actually a waste area within the Nevada National Security Site.
Its easy to see right through the BS this author has laid out. Its a shame he doesn't seem to care about his own credibility. Just another asshat that does nothing but talk. Its a shame, because there are legitimate issues here to discuss, and it helps when the facts are laid out in a responsible manner.
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Its easy to see right through the BS this author has laid out. Its a shame he doesn't seem to care about his own credibility. Just another asshat that does nothing but talk. Its a shame, because there are legitimate issues here to discuss, and it helps when the facts are laid out in a responsible manner.
Yeah, getting information on nuclear anything from an anti-science, anti-nuclear political lobby group with a grossly misleading name is not a good idea.
When I saw the organization promoting this I didn't bother to read it--life is too short to waste time debunking nonsense by political lobbyists who have zero credibility outside their little bubble of fanatical and fact-averse supporters. So thanks for taking the trouble to slog through the sewage and point out some of the howlers.
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"Other than a dirty bomb?" Yeah, that's comforting. A big fizzle that spreads nuclear contamination across half of New York wouldn't kill as many people immediately as a fat-boy style fission explosion would, but it would create an economic disaster of truly epic proportions. Net effect on the country would probably be worse. Hiroshima has recovered from its nuclear attack, because the fallout was over with quickly. That wouldn't be the case with a U-233 fizzle.
Just because someone finds fault in
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The material is harder to acquire than other suitable material, hence its existence is less of a threat.
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Yeah, real hard to acquire.....
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In that case, you REALLY don't want to think about all those basements with radon gas or all those smoke detectors out there.
Meanwhile, I would suggest de-enriching that U233 and fueling a reactor with it. That way we get rid of it and we get energy.
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Google "Radioactive Boy Scout". There is no need to steal guarded U-233 to make a dirty bomb.
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Or, if you blindly trust the author's claims and statements, just say it.
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Well, to spread across "half of New York", said bomb would have to be of very large explosive yield, and hence by definition, NOT a fizzle. Or have you perfected radiological contamination via glowing fairies riding unicorns through the Manhattan street grid? Do tell.
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The trick is convincing the fairies that the Uranium is actually fairy dust. It's smooth sailing after that.
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Re:questionable commenting (Score:5, Insightful)
Well, I am a physicist, and I think that the article was badly written and intended to produce more heat than light. If the author has heard such complaints and believes they have been addressed, he sure didn't do a good job doing so.
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As a non-physicist I have to agree that the article was badly written and was setting off alarm bells the whole time I read it.
If you have a good point you can generally make it fairly clear and precise.
If you don't you end up stumbling all over the place in an attempt to justify it and avoid the weak points.
About the author (Score:4, Interesting)
Apparently Robert Alvarez does not think that people do background checks. This article was dated June 13, 2011:
http://atomicinsights.com/why-does-anyone-trust-robert-alvarezs-opinions-about-nuclear-energy/
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That explains the smell.
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I don't believe you. With such impressive written language skill, "your" clearly an English professor.
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LMOL, yeah your a physicist.....it's my lunch hour so I'm a gynecologist....moron...
WTF? What's so hard to believe about mbone being a physicist? There are plenty of highly-skilled and very intelligent people on this forum.
Your post does lead me to wonder if you wouldn't find a different discussion group more suited to your tastes, say, /b/ perhaps? As a bonus, you won't need to furrow your brow using that pesky written word thing there.
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Have you ever run a technical program? If you do so (and I have, a number of times), you frequently have to evaluate technical statements by subject matter experts in areas that are not directly your field. Remember that in physics claims from authority are meaningless, all that counts is the evidence and how it is presented, and you certainly should challenge claims and statements that do not appear to be supported by the evidence. I have said nothing here I wouldn't say to Mr. Alvarez in person, should I
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I'd say Alvarez' use of self-citing in that FUDicle is the truly arrogant thing.
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Parent seems unable to distinguish between his own non-expert opinion and the opinion (true or not) of an expert with long history in the study of this subject matter.
If parent can think of a criticism, it's a safe bet the author has heard it before and believes it has been addressed. Unless parent has evidence that the author is unaware of these concerns, or intentionally misleading the reader of the article, he is just being arrogant.
The fact that it looks like a glaring hole to you (non-expert) doesn't mean it really is.
While I'm no nuclear engineer, I have heard that Alvarez has a rather poor reputation in nuclear circles.
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Parent seems unable to distinguish between logical reasoning and an "argument from authority" fallacy.
The GP has pointed out valid concerns with the article.
"But Bob said so!" is not a valid counter-argument.
Mystery lead (Score:5, Funny)
uranium 233 has been created, and 96 kilograms of the stuff (enough to fuel 12 nuclear weapons) is now missing from the US national inventory
In addition, they have about 96 kilograms of lead that they don't remember ordering. And the situation gets worse every day!
Re: Mystery lead (Score:5, Funny)
The situation is only half as bad as you might think.
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There's no lead?
Re: Mystery lead (Score:4, Funny)
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uranium 233 has been created, and 96 kilograms of the stuff (enough to fuel 12 nuclear weapons) is now missing from the US national inventory
In addition, they have about 96 kilograms of lead that they don't remember ordering. And the situation gets worse every day!
If they started with 192kg of U-233, there'd be a lot more than 96kg of U-233 and a lot less than 96 kg of Pb around at this point [periodictable.com].
Re:Mystery lead (Score:5, Funny)
If you think this joke went over badly with actual Nuclear Physicists, you should have seen the blank stares I got when I tried it out on a crowd of English majors.
Calling Kirk Sorenson (Score:4, Interesting)
This trash piece gets things wrong on so many levels it isn't funny. For the real deal, follow Kirk Sorensen's blog.
Watch this video by McDowell, he lays it out. All that so called "waste" is fuel for a SNACR reactor design that would eliminate the waste entirely.
http://www.youtube.com/watch?v=P9M__yYbsZ4
The LFTR is a different type of reactor (Score:2)
The article seems to refer to conventional fission reactors that use thorium mixed in with uranium. I think Bill Gates has invested in a company that pushes that. McDowell's excellent video is about the Liquid Fluoride Thorium Reactor, a much safer design that takes a bit of Uranium 233 as its seed and breeds it out of thorium, never creating a high concentration and burning almost all of it before refueling. A conventional reactor leaves over 99% of the energy in the spent fuel; a LFTR leaves very littl
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5. Profit.
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Dispose of U233? (Score:2)
Why throw it away? Can't it be diluted down to reactor fuel grade material? I thought a significant amount of our current supply came from retired weapons. Maybe that only applies to plutonium.
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Different isotopes. This is basically highly radioactive waste, unless you want to burn it in a thorium reactor (which we are not pursuing at present).
Re:Dispose of U233? (Score:4, Interesting)
I believe that the Nevada Flats facility is basically just "storage" in this context. However, if you read this [doe.gov], you will see that most of the material is in other forms, such as "Molten Salt Reactor (MSRE) traps, Oxide powders and Zero Power Reactor Plates," and that potentially critical material will be "downblended," "driving the U-233 concentration below criticality and security concerns. It is to be dissolved and then downblended with depleted uranium so it can be disposed safely."
In other words, it's not like that they will put bomb components into a landfill, but everything will be converted to some form where it would be fairly complicated to make a bomb out of it.
Sihg... Not valid. (Score:5, Informative)
Thorium when used as a reactor fuel does not involve separating the U 233 from the spent fuel. A small amount of 233 can be used to start the reaction but you burn the 233 in the reactor fuel that breeds it. It is also full of FUD.
"The last serious attempt to use thorium in a commercial reactor was at the Fort St. Vrain plant in Colorado, which closed in 1989 after 10 years and hundreds of equipment failures, leaks, and fuel failures."
The problems had nothing to do with the use of thorium fuel. It had everything to do with a badly designed cooling system that used He instead of water.
I just not have time to shred it but it is just terrible FUD! Look up the Fort St. Vrain reactor yourself to see the reports on the problems with the He system. They used bad water seals that leaked into the cooling circuit that caused the problems.
In other words this article has nothing really to do with the Thorium reactors that are being proposed today. Not surprising since samzenpus is know to be anti-nuclear.
Re:Sihg... Not valid. (Score:4, Insightful)
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Thorium reactors being a total non-starter is about the only thing this article has gotten right. Everyone hand-waves the most critical and problematic issues with thorium fuel.
Thorium fuel reactors WILL require fuel reprocessing. This is a toxic, messy, and dangerous process. All thorium proponents paint this issue as a trivial issue to be worked out but 50 years later all we have are a handful of research reactors facing the same problem.
The above reason is why molten salt reactors don't work. There is no
Re:Sihg... Not valid. (Score:5, Insightful)
Much of the reason that it hasn't been developed after 50 years as you say is because the people writing the cheques for nuclear research want dropable/launchable nukes that they can blow up the planet. So when someone suggest a possible safer option that does not produce the wanted isotopes for making a big boom, it gets very little funding.
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Indeed, I much prefer my radioisotopes bound up in solid cladding. A molten salt reactor seems to combine the difficulties of a reactor and a reprocessing plant in the same package - except worse, because normal reprocessing plants work on fuel that's had a couple of years to cool off.
They also solve a problem that right now doesn't exist - there's no shortage of uranium.
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Re:Sihg... Not valid. (Score:5, Interesting)
Okay, maybe, MAYBE, if you were talking about a solid fuel reactor.
If you want to say "Thorium is dumb in a solid fuel reactor", I'd say "Yeah! You're right! It is!"
But take a look at a Liquid Thorium reactor
Basically you put the fuel in and pretty much let it burn through it's fuel supply.
You also have NONE of the problems involved in a solid-fuel reactor. Most of the failsafes become passive, rather than engineered.
Not only that, several of the byproducts are actually medically or scientifically useful (U238, which gets used in deep space device batteries), etc. The rest of the byproducts are things that are, yes, DREADFULLY radioactive...for a few days/weeks. Then they break down into stuff that's about as harmful as eating a banana.
What's more, Thorium is orders of magnitude more plentiful than most of the other stuff we're currently burning in reactors. Just the tailings that come up from current mining concerns can produce more power than the US uses in a year.
ON TOP OF THAT, actual use of Thorium would allow rare-earth mining to pick back up in many places around the world.
We need to do this because, otherwise, in 20 years' time, we're going to be buying Chinese-built Thorium reactors.
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In theory, only the theoretical properties of a technology matter. In practice, though, the implementation matters. The fact that an implementation that failed was done poorly isn't really comforting unless there is some reason to believe that in the future it would be done better (not just differently).
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Knowing that an implementation was done poorly, we can then ask: what was poorly done? Then, the Nuclear Regulatory Commission can refuse fuel to implementations making similar mistakes.
Highly-regulated industries face one major advantage: you cannot fuck up in any way related to a prior fuck-up. If your coolant system fucked up because of an improper valve design, your entire coolant system will now require strict testing and engineering standards--meaning other, substantially dissimilar designs tha
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Fukushima is a hell of a big deal. And the NRC has historically shown that it is not willing to actually regulate the industry in any serious way. Can you cite an example of them shutting down a plant an operator wanted to continue operating, as you suggest they would? That's precisely the problem! If I believed that nuclear regulation could be depended upon to have real teeth, I'd be less concerned. History on this subject is not hopeful. Fukushima was predicted, and would not have happened if
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I just not have time to shred it but it is just terrible FUD! Look up the Fort St. Vrain reactor yourself to see the reports on the problems with the He system. They used bad water seals that leaked into the cooling circuit that caused the problems.
It's rather harder to make a leak proof system with helium, an inert gas compared with water, a highly polar
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Sadly, valid (Score:5, Insightful)
The problems had nothing to do with the use of thorium fuel. It had everything to do with a badly designed cooling system that used He instead of water.
The Ft. St. Vrain story is rather sad. The plant had a large number of minor problems that made it too expensive to run. It was converted to natural gas.
Every reactor design which had something complicated happening within the radioactive parts of the system has been a commercial failure. Standard boiling-water reactors and pressurized-water reactors are very simple both mechanically and chemically inside the reactor vessel. All the complexity is outside, where it can be fixed if necessary.
Sodium-cooled reactors have sodium fires. Pebble-bed reactors have jams. (There's a prototype in Germany that's so jammed it can't be decommissioned.) Helium-cooled reactors have leaks. Reactors which require an adjacent chemical processing plant have all the problems of a chemical plant for radioactive materials. Anything which goes wrong in the radioactive part of the system is a huge deal to fix. The history of exotic reactor designs is not good. Many of the exotic ideas have been funded and built, but the results are not impressive.
Meanwhile, boring old BWR and PWR reactors have a long life and good uptime.
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Interestingly, according to the Wikipedia article, the plant really did well - as a test bed and proof of concept. It had major engineering issues, as test installations often have. A second plant with lessons-learned might have been successful.
It was decommissioned on time and at cost (other references).
Apparently there is one other reactor with the same technology slated to go online in 2021. So it appears that Thorium cycle plants are viable, just not particularly easy or inexpensive.
Never before??? (Score:5, Insightful)
" Never before has the agency or its predecessors taken steps to deliberately dump a large amount of highly concentrated fissile material in a landfill, an action that violates international standards and norms."
Clearly this person knows nothing about what happened during the cold war at Rocky Flats, Hanford, and the Savannah River sites.
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And at the supposed "clear up" after accidentally dropping nukes at Palomares in Spain. Where it has since been discovered that they just dug some shallow trenches and buried a pile of plutonium. Guess they hoped no one would ever notice...
Landfill? (Score:5, Informative)
On top of that, the federal government is attempting to force Nevada into accepting a bunch of the uranium 233, as is, for disposal in a landfill (the Nevada Nuclear Security Site).
http://www2.nstec.com/Pages/in... [nstec.com]
This isn't some hole in the ground full of coffee grounds and soiled nappies.
Send it to the sun (Score:2)
Really, comic books having been doing this for years...
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Really, comic books having been doing this for years...
well they had superman in the comic, we here in reality have space shuttles like Columbia, and Challenger, and rockets like Apollo 1. If we were in a comicbook universe why not just have superman spin a turbine and give us unlimited energy.
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Because without Superman, Lois Lane's stupidity kills her, duh.
Even Lex Luthor can't fix stupid.
"50 years" (Score:5, Informative)
For 50 years the US has tried to develop thorium as an energy source for nuclear reactors, and that effort has mostly failed.
Actually, it really hasn't.
It experimented for 10-15 years with thorium, early in the history of the nuclear age, until it was established that you can't really make a lot of bombs from the by-products of thorium reactors. And then it moved funding toward uranium-based systems.
There hasn't been much meaningful research into it since about 1969, when ORNL shut down its MSRE.
It'd probably be worth setting up a few not-too-large reactors just so we can burn up some of the nuclear "waste" (read: 'unused fuel) from the current uranium-based reactors.
Real Reasons Thorium is Being Held Up (Score:5, Informative)
1) The liquid medium that is actually containing the fission events is incredibly caustic. This means that the reactor vessel, in addition to dealing with a very high neutron flux, has to handle severe corrosion issues at the surface. The fact that it is done at STP does not provide any help. 2) The salt 'plug' that is often cited as a major safety asset for the LFTR has some major engineering obstacles that have been be able to be addressed yet. 3) The liquid medium has to undergo re-processing on a fairly frequent basis. This is non-trivial as the medium is highly caustic and radioactive. The products pulled out are also highly problematic. This is probably one of the biggest hurtles for LFTR. It is a costly and messy chemical process.
There are other smaller problems, but these are the 'big three' I can recall.
For next-gen reactor tech my money is either on traveling wave type reactors (which never need to be refueled for its entire lifespan..30-100 years). Look up the Toshiba 4s for the furthest along reactor.
There are also sub-critical 'energy amplifier' reactors that use a particle accelerator to drive a proton beam into a spallation target (lead) which causes a neutron flux suitable for fission events to occur, though not enough to cause a self-sustaining reaction. Only 10% of the energy is required to be redirected back to the accelerator (fission rules like that). This one has the advantage of being able to use pretty much any fuel, and waste we have as well as reducing the daughter products to benign isotopes. Belgium is currently in the process of building one.
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RE: 2) The salt 'plug' that is often cited as a major safety asset for the LFTR has some major engineering obstacles that have been be able to be addressed yet
Can you list a few of these "some major engineering obstacles" ?
The only salt plug I've read about are "Freeze plugs" that melt upon "a bad thing" happening.
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I also think sub-critical accelerator-driven systems (ADS) are a good way forward, since we have so much darned nuclear waste. Right now, the power level required for economical ADS is still a bit out of reach.
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Thank you for posting this. I'm rather tired by the constant stream of posts here that claim if we just switched to Thorium/Helium-3/Unobtainium, we would have all our energy problems solved by the end of next week. It's good to see an intelligent discussion of the real engineering problems involved for a change.
Consider the source. (Score:2)
As I was reading that article, my thought was "Who wrote this crap?" Tendentious scare-mongering and blatant misrepresentation of ... practically everything he mentions.
Then I looked at the URL at the top of my web browser. thebulletin.org. Ah. Figures. If I'd looked at where that link went before I clicked on it, I'd probably not have bothered.
Ah well, looking on the bright side, at least it wasn't a goatse link.
Obvious troll is obvious (Score:2)
What a load of textual diarrhea. A bunch of whining about how dangerous U-233 is, and little else. Hey Alvarez, why don't you go swimming in a coal plant slurry pond, since that's what your disinformative pack of lies has the end result of promoting? At the very least, if you were interested in at least some plausible level of credibility, you wouldn't go using YOUR OWN agenda-laden [toilet] paper as a citation.
Bottom line: Fuck off.
Not exactly yellow, but.. (Score:2)
Can we dispense with adjectives such as "terrific" that are clearly subjective judgments in describing an article, especially one as biased and contested as this is?
bomb making potential (Score:2)
Numerous Factual Errors (Score:5, Insightful)
That article comes of as an attack piece from someone who feels threatened (maybe someone with serious investment in traditional reactor tech?). He makes ridiculous claims about the US spending decades trying to get thorium reactors working (we did not), and about many companies trying to create thorium reactors in past decades (they did not), and makes scary claims about a small amount of thorium 233 and its potential to make bombs (far more refined plutonium and uranium exists and is more easily weaponized). The truth is, the US made only one test thorium reactor decades ago, and it proved the potential for a sustained thorium cycle. The current research challenge is only around extracting waste products from the molten salt fuel mixture, and that is well within our technical capabilities. The only thing stopping the development of working LFTR reactors is the will and funding to do it.
I would pick apart the article in more detail, but I suspect other people have already beat me to it.
Thorium - a classic acadmic reactor (Score:2)
Dumping U233 is a good way to kill LFTR (Score:2)
U233 is the limiting resource for starting a thorium economy [youtube.com].
Dumping it is a good way to kill LFTR as an energy source.
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With a purposeful grimace
and a terrible sound,
he pulls the spitting high tension wires down,
GODZILLA!
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Orbital mechanics. It's why they call'em rocket scientists.
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The problem with hitting the Sun is that you are starting out with the speed of the Earth around the Sun, approximately 30 km/s. Only if you manage to decelerate an object to a speed of 0 it will hit the Sun. Anything else will start to orbit the Sun, and if started out from the Earth orbit, it will have an orbit that crossed the Earth orbit, not to mention that it will also cross the orbits of Mercury and Venus, and might get
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It's not actually difficult, it's expensive. The thing is, because we're not dealing with an inertial system but with a rotating system, we need to cancel the orbital velocity in order to actually hit the Sun. One figure I've seen puts the velocity we need to achieve at 32 km/s. Escape velocity for Earth amounts to 11 km/s, by the way.
That's quite a lot and makes the whole thing a bit impractical (Rockets don't scale well and, according to the calculations I've seen, a Saturn V would only have a payload of
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Well you certainly need to lift the material out of the gravity well of the Earth, and that, by itself, is not practical. Expensive and dangerous.
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Well, that was pretty much a given form the start ;)
Re:We should use the moon as a hazardous waste dum (Score:5, Funny)
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Doesn't work. You'd still need to cancel Earth's orbital velocity - which means that you'll have to achieve a velocity of about 32 km/s (in contrast to merely 11 km/s to escape the gravity field of Earth). Which means that a "gentle nudge" won't do.
Re:We should use the moon as a hazardous waste dum (Score:5, Insightful)
Yes. And that solar-collision orbit requires a speed of 31 km/s. You're forgetting that you're on an elliptical orbit around the sun - every nudge towards the sun merely reduces the smaller axis of the elliptical trajectory around the sun.
The "nudge" would work if both objects (target and object to push) were at relative rest. But they aren't at rest. You start out with the Earth's orbital velocity around the Sun.
That, by the way, is also the reason why missions to Mercury are rare - it's quite expensive. By the way: Shooting stuff completely out of the solar system would only require about 41% of the energy you need to get to the Sun. Sounds weird, but that's orbital mechanics for you.
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to big of a deltaV to counter the earths angular momentum and drop into the sun you would probably just end up with a very erratic orbit
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In other news, U233 decays into Sn120 through antiproton emission. Hatmakers' stocks are up 140%.
Oh, wait, no, actually, further research reveals that the last part was caused by your post.