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Amec Working on Long-Term Nuclear Waste Solution
Ckwop writes "The Daily Telegraph is reporting that Amec, the company that cleaned up Ground Zero, have developed a new process for storing nuclear waste that lasts two hundred thousand years - far longer than any radioactivity will last. The process works by mixing eighty percent soil with twenty percent waste and then heating the mixture to three thousand degrees centigrade. When the mixture cools it forms into a glass harder than concrete. While this is not the first waste process of this type it is the first to be cost effective and produces a glass much harder than previous methods. " We'll see if we still need a ten mile field of spikes I guess. A pilot facility is being built in Washington State.
After R'ing TFA, it looks like this is nothing new, just a slightly better method of vitrification. I don't know, the tone of the FA was a little, um, enthusiastic for an incremental improvement to an established method...
A house divided against itself cannot stand.
This sort of thing is done already, and often glass is packed inside a metal layer/container. Take transport: if you got fluid components, dust, or pressurised gasses, and there's an accident, the stuff spills all over the place, and into air, ground water. If it's glass, it may go in pieces, but the pieces stay were they are, with the radioactive material trapped inside.
The Vitreous State Lab at The Catholic University of America has been doing this for 30 years. Read a recent article here.
There will be some residual radioactivity in any nuclear waste forever - I presume that they meant far longer than the half-life...
I assume they probably mean until the radio activity falls to around background level.
Doing a quick back of the envelope calculation I computer that if the half-life is 10,000 years than after two hundred thousand years the radioactivity is about one hundred thousandth of a percent what it is today.
Simon.
I can't seem to figure out which planet you're from, but if your homepage URL is any clue, the British cars kill just under 3,000 people every year. In case you're a yank, that figure goes up to a bit over 40,000. I'd like to see this super-duper-hyper jumbo jet of yours.
Money for nothing, pix for free
Rubidium 87 has a half-life of 47 billion (10^9) years (our soloar system is not yet 5 billion years old). Uranium 238 has a half-life of 4.5 Billion (10^9) years, Plutonium 239 has a half-life of 25.000 years. Half-life means that after some billion years, you still have half of your nuclear waste happily emitting radioactivity, while the other half has decayed to other, possibly also radioactive elements. After 7 times the half-life (7*47*10^9 years = 329*10^9 years), you still have round about 1 % of the original radioactive waste (2^-7 = 1/128 ~ 1%) and a lot of other radioactive products.
There is no final solution of nuclear waste, and there probably will never be one. It is practically impossible to guarantee a safe place for at least 7 half-lifes of Rubidium 87 or Uranium 238. Even if you can dig a deep hole and fill it with nulear waste, there still is a possibility much larger than zero that someone digs it out again in some thousand years and does not know what that shiny stuff is. There have already been accidents in third world countries, where poor and uneducated people digged out radioactive materials from medical devices on waste dumps. And a mountain used to store nuclear waste may erode before the waste becomes harmless.
Lessons learned: PR people don't know anything about mathematics and radioactivity.
Tux2000
Denken hilft.
Although "harder than concrete" sounds "strong" it does not address the chief danger in long-term storage. Chemical erosion and leaching are a bigger issue than brute strength. Anyone who has ever thought about geology and objects like geodes will realize that quartz is both much harder than concrete, but also (over the long term) water soluble. The real trick is to encapsulate the waste in something that won't dissolve or allow the migration of waste isotopes in the heat, potential liquids, and long timescales of waste storage. (I'm sure hardness is somewhat of an issue when trapped alpha particles and decay products create expansion stresses in the glass)
I do think that vitrification is the way to go, but statements like these do the public no good when they mislead them on what characteristics actually make for a good containment system.
Two wrongs don't make a right, but three lefts do.
Of the top of my head... There was some discussion and research done a while back to establish what sort of symbolic warning to future generations we could use on the surface above extremely hazardous waste such as long half-life radiactive material. The idea of using a lot of large monolith type needles came up, these were supposed to be truly massive and the idea was to convey 'dont dig here', or something. It seems pretty sensible to at least try and warn future generations about an area such as a geologic waste depository but what if the warning signs get misconstrued? If we ever wipe our selves out, which is more than likely in my opinion, then would the next round of intelligent life understand what we ment? Might not such a legacy raise the same kind of curiosity that we have and lead to some archealogical dig only to get themselves zapped...
my other sig is written in brainfuck
Yes, but of course what is needed is not a package that will last until any radioactivity has disappeared, but a package that will last until the remaining radioactivity is negligible compared to the normal background radioactivity.
You only need to run it for long enough to get to the point where the waste mixed with the carrier is slightly less radioactive than the ore you originally mined. Then shove it back down the mine (or dig a new equivalent) and the whole cycle reduces the radiological hazards in the world.
_O_
.|< The named which can be named is not the true named
One of the waste products produced by nuclear reactors is Iodine-129. The half-life of I129 is 15.7 million years.
You'll have a greater risk of radiation exposure from going outside on a sunny day than from all the iodine-129 in the world. The point about keeping an eye on iodine-129 is because it's found together with the more dangerous isotopes, iodine-131 and iodine-133, which have half-lifes of 8.02 days and 21 hours respectively, making them very active and dangerous substances:
From http://www.jaeri.go.jp/english/press/2001/011017/ (Japan Atomic Energy Research Institute):
Among the radionuclides emitted during a nuclear accident, the Iodine (131I, 133I) isotopes exhibit strong radioactivity that affects the human body but they are difficult to quantify because they have short half-lives and turn quickly into stable, non-radioactive substances. On the other hand, the iodine-129 that is hardly hazardous at all due to its long half-life period is emitted at a certain ratio with respect to iodine-131 and iodine-133. The measurement of iodine-129 makes it possible to estimate the emission of radioactive substances such as iodine-131
Iodine-129 by itself is hazardous for roughly 0 seconds, 0 minutes and 0 years. So which physics course did you take again?
No offense intended to the people of the article, but some of that waste (if we are talking used fuel elements) still contains Uranium and Plutonium which has a half life of 10^8 years. [...] My humble opinion is that this technology is used after the really long lived nasty stuff is separated and destroyed
The long lived isotopes of uranium and plutonium are not a big concern. They are not very radioactive at all precisely because they have such a long half life.
You'd rather I didn't correct it?
I'd rather you not correct it with a half-truth like say, oh, picking an extremely long-lived compound whose contribution to the total radioactivity of the waste is minute at best.
Plutonium also has a very long half life.
24000 years, IIRC. As you admit yourself, after 10x the half-life (=240000 years, in the same ballpark as the 200 000 years claimed) most of the radiactivity from plutonium has disappeared.
I assume you wouldn't eat it for breakfast.
Of course not. I wouldn't want to eat any other heavy metal for breakfast either, they all tend to be quite toxic to biological life.
It would take more energy to launch the rocket into the sun than you'd get from the nuclear fuel in the first place. People think that the sun is an easy target because it's "down" in the gravity well, but you have to remember that you're starting with earth's orbital velocity, which you need to cancel out to 'fall' to the sun. That's about 18.5 miles/second.
Its an idea I've heard mentioned before (can't remember where) and on the face of it, seems like a good one. However, I'm not so certain it would be a cheap method of disposal. If I remember my college geology, most of the subduction zones are under water, which would raise the cost of drilling the disposal hole. Also there tend to be earthquakes along plate boundaries (including subductions zones) which might collapse the disposal hole, making re-drilling necessary.
Also there there tend to be volcanoes associated with subduction zones -- would this mean there's a risk of particularly radioactive magma?
People think that the sun is an easy target because it's "down" in the gravity well, but you have to remember that you're starting with earth's orbital velocity, which you need to cancel out to 'fall' to the sun. That's about 18.5 miles/second.
Easily achievable. 18.5 miles/sec is roughly 30 km/s. So, you need to cancel that energy? Well, that's 450 megajoules per kilogram you'll need to put in. I believe you get _substantially_ more power than that out of fission reactions.
That's about the same amount of output as 17 modern LWRs. THe PBMR is well suited to areas without an existing electrical infrastructure. Using PBMRs to power the U.S. isn't practical and that's not what they're designed to do.
Now if you built 100 additional LWRs and double the nuclear power production in the U.S. (up to 40% from today's 20%) you'd have a massive impact on greenhouse gas emissions (We'd be able to join the Kyoto protocol) and reduce our reliance on foreign sources of natural gas. Very little oil is used for electricity generation in the U.S.
Heating the soil up that high to melt it into glass will also vaporize the lead and send it into the air.
It's been around here since 1969, and still used today in La Hague nuclear repocessing plant. You will find many details (in english) on the web site of the CEA (Commissariat à l'Énergie Atomique), a governmental agency. They say that glass packages are guaranteed for millions of years.
There's plenty of Uranium in spent fuel rods. Trouble is, the Uranium is not longer "enriched" and cannot be used in a conventional nuclear reactor. You can build reactors to run off the waste, and you can re-proccess waste to get the fuel out, but both approaches lead to their own problems.
Also, the grandparent seems not to realize that the "main isotope" of Urainium is U-238, which is mostly harmless (you'll notice I didn't say "totally harmless"). You can't built a fission bomb out of it, it's worthless as fuel and it hardly glows at all (the radioactivity is feeble). U-235, the stuff in "enriched" Urainium is the weapons grade stuff (and the fuel in fuels rods). Highly radioactive/short lived (relative to U-238).
Waste still has U-235 and sometimes Plutonium as well, but the real trouble is the fission by-products you get from using it. The by-products in question are short lived, radioactive and often have other nasty characteristics. Luckily, they can be contained until harmless (decades to centuries typically, nothing like 200,000 years).
Erotic is when you use a feather. Exotic is when you use the whole chicken.
I remember reading a fascinating article on how to warn an unknown future civilisation about high-level nuclear waste. One suggestion included a huge field of spikes.
Quite a tricky problem - the researchers reckoned one of the key tasks was to make it look important but obviously valueless in order to prevent tomb robbers (after all, the Egyptian curses in the pyramids din't work too well).
Unfortunately, I can't seem to find it online, though some of the same material is covered in:
"An Architecture of Peril"
http://www.arch.ksu.edu/seamon/Brill.htm
The faster a substance decays, the more energy it emits. Conversely, substances which only decay very slowly emit very little radiation. Thus U-238, with it half-life of 4.5 billion years is far less radioactive than, say, Carbon-14 with its half-life of approximately 5,730 years. There are, of course, different types of decay, and heavier atoms tend to decay producing alpha particles and gamma rays rather than the beta particles that are common in lighter elements. Even so, elements with half-lives measured in millions of years do not typically emit enough radiation to be a threat to humans or to nature. The intensively radioactive products tend to get rid of themselves, so it is the medium intensity materials, such as the infamous Sr-90, with half-lives measured in months to millenia, that are particularly dangerous. It is also worth noting that alpha, beta and gamma rays can not make materials radioactive - it is neutrons that do that - and that alpha particles, which are the least penetrative of the three primary radiative products of nuclear decay, are also the most strongly ionising, while gamma rays, the most penetrating, are the least ionising, given the fact that they consist of mere EM radiation rather than charged particles like alpha and beta rays.
Humans are exposed to ionising radiation every day, and have been during the entirety of history. For this reason we have a variety of genetic repair mechanisms. The mere presence of ionising radiation is not a matter of concern; under normal circumstances the most significant sources of such radiation are natural. It is only when the level of radioactivity overwhelms the body's natural defenses that radioactivity becomes a threat to human health.
An error in the story:
Plutonium has a half time of 44.000 years.
If you put 1 kg plutonium in a glass block, after 44.000 years 500 grams are still there. After 88.000 its down to 250 grams, after 200000 years still 30 grams are left. So if you put 10 kg into such a block, after 200000 years still 300 grams are left.
The press release of the research team is missleading as well. In germany the deposition of waste, radioactive or not, in different kinds of glass is a long researched topic.
At my town where I live is the research center, and I know people involved in such researches.
Most glasses are somewhat vulnerable to acids. So the question, still to answer is: where to deposite the glass blocks? In germany it was for a long time an idea to place them in salt mines (we have a lot under surface piles of old stone salt).
Salt mines are considered "dry", very dry. However: a lot of salt compositions contain so called "crystal water". That means a crystal, a kind of big mollecule, contains captured water.
The ionisating rays of decaying material can break up such molecules and the water is set free. As such water can dissolve salt it can become to an aggressive acid which even harms very robust glass kinds.
Now you would think about a protecting surface over the glass blocks, that wont help much. Most places where you would store the glass blocks, will eventually be covered by the montain. The pressure if the mountain moves likely cracks a block once a while, and that block then is vulnerable to aggressive acids.
That said, glass blocks surely are a "quite save" way to handel our current problems. But they are no holly grail like the industrie likes to tell us.
Interesting is: in germany the research results are not public disclosed. In politics its still talked as if salt mines would be a perfect storage, but a granit mountain would be likely much better. I guess if you ask (or search for PDFs) you might get the information easyly, its an EU sponsored research project. However in media its not covered: htp://www.fzk.de (or probably the institute site: www.ine.fzk.de -- I did not check if they have their own site)
angel'o'sphere
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
Dumping this glass on the sea floor still means we'd wind up with irradiated fish and coral.
Or we drop them into tectonic subduction zones. The glass would (eventually) get pulled into the earth.
"I don't know, therefore Aliens" Wafflebox1
I believe his name is Wile E. Coyote but I could be mistaken. Not that it really matters anyway...
Not everything is analogous to cars. Car analogies rarely work.
The process is called instuvitrification and has been in use for several years. I saw a demonstration site at Oak Ridge National Laboratory when I worked for a subcontractor and took a small sample as an interesting artifact. It used to sit on one of the curio shelves in my apartment. The glass was green and had spherical bits of metal about the size of marbles imbedded in it. It was pretty cool.
Except glass is actually a liquid, and flows quite readily on a scale of centuries, let alone millenia, and you wouldn't want groundwater carrying any surface contamination off those glass blocks.
Christ, is that urban legend still around? No, glass is not a liquid.
ZFS: because love is never having to say fsck
Hey, if Mama nature can do it, we should be able to pull it off.
//Information does not want to be free; it wants to breed.
Sustainability and energy independence essay
Using lead to shield against beta particles is actually worse than using a sheet of plastic. The beta particles usually cause the lead to kick out a whole slew of other varied emissions, as opposed to just being absorbed.
But this idea is not entirely new, in fact it would have first been mentioned in the 1960s if not before. Still, it is a good idea, whose time maybe has come at last.
FWIW... from one who believes we probably DO need more nuclear-fueled power-generating plants... at least until we find something better.
In TFA, "Amec says that its latest process will enable nuclear waste to be stored safely for 200,000 years - longer than the radioactivity will last."
The courtroom dictum, "false in one thing; false in all," may not be entirely applicable here, but you may wish to take a grain of salt with Amec's claim that its vitirification process can outlast the decay processes.
The half-life for a radioisotope is the time for half the radioactive nuclei in a sample to decay. In other words, after two half-lives, there will be one quarter the original sample left (and emitting alpha, beta and/or gamma radiation) and after three half-lives one eight the original sample will remain.
Half-lives range from tiny fractions of a second to many, many times the age of the universe.
Plutonium239, for example, has a half-life of 24,300 years; Uranium238 has a half life of 4.5 billion years.
The U238 decay chain inclues other radioactive materials (U234, thorium, radium, radon, bismuth, among others). The end product of the decay chain is lead206 which is stable; ie, not radioactive. The preceding elements in the chain each have their own half-lives, ranging from 247,000 years to 1e-5 seconds.
[this sig has been trunca
The process itself is not the issue here in the US and this will not solve ANY of our current problems. Having worked on bothe the Low Level and High level waste respoitories here in the states, I know the issue is getting the waste to the facilities, not the storage itself. The criteria for stability for the sites chosen today were 100 million years, not 200,000. So the storage length is not an issue. No body want to allow the waste to be transported over their roads, through their neighborhoods to get to the facilities. Dispite the Low level facility being operational for nearly a decade now, they have yet to recieve any waste due to this issue. I guess peoplewould rather have this stuff in their backyards rather than safely buried.
While I personally don't have any problem with nuclear power plants, I would point out that Japan also has nuclear related accidents every few years. There was one earlier this year, and then 2000ish there was the one where they put too much uranium compound in a bucket of nitric acid.
Also I'd need a lot of trust in the operating system too.
The idea that plutonium is "one of the most poisonous substances on earth" is complete nonsense. In fact, plutonium barely qualifies as a toxin at all. Yes, it can cause cancer, which may eventually kill you. But lots of substances will kill you far more quickly at far smaller dosages. Some that are quite likely present in your neighborhood include digitoxin (foxgloves), convallaria (lily-of-the-valley), and aflatoxin (food molds). And substances such as Indian cobra venom, ricin, botulism, or anthrax are so much more toxic than plutonium that there is really no comparison.
Actually this is exactly what has happened at the Savanah River site. Wildlife is doing well there and no on wants to go there :) :)
Seem nuclear waste is less dangerous than people
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.