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Thorium: The Wonder Fuel That Wasn't
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.'"
Interesting caption to use as the summary.
"Here Lies Philip J. Fry, named for his uncle, to carry on his spirit"
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.
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!
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
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.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
" 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.
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...
This isn't some hole in the ground full of coffee grounds and soiled nappies.
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).
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.
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.
After doing a lot of research into the current state of Thorium technology I was able to find the following non-FUD conclusions as to why Thorium and LFTRs in particular aren't working out so well.
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.
Didn't the hazardous nuclear waste storage site on the Moon explode and throw the Moon out of the solar system in 1999?
I believe that the Nevada Flats facility is basically just "storage" in this context. However, if you read this, 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.
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.
That explains the smell.
No brain, no pain.
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/
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.
The Bolachek Journals
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.
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.
The Economist had an article about thorium reactors recently too. It was a bit rosier than this one. Anyway, all this press I've seen recent about thorium reactors reminds me of an article Admiral Rickover wrote in 1953 about the difference between academic and practical reactors. It's a good read, and there are definitely parallels here.