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Nuclear Waste Disposal

Magnetic Rail Gun shoots Nulclear waste at the sun
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I bet this one is baked and out of the oven, but I haven't been able to get anyone to tell me why this wouldn't work. For those who don't know, Magnetic Rail Guns are guns that work, well, with magnetic rails the propulsion mechanism. This allows higher Initial Velocity than rockets and is cheaper, but g's of that sort kill people and crush electronics. But if we had tightly sealled cannister of Nulclear waste, we could have this thing whooshing stuff to the sun on a schedule. It isn't going to damage the sun. Heck, we could throw the whole earth at the sun and not phase it. There can be safeties built in incase the cartridge didn't make it out of our atmosphere.

You may argue that there is no saftey good enough, but I counter: is it safe leaving it in the ground ?

Get that stuff off of my planet, and set the reactors free !

ceresian, Jun 28 2000

(?) Lots of comments ! Great! I http://www.sover.net/~geoffk/railgun.html
Whatever you may say, the idea is certainly in the oven...see this url. [ceresian, Jun 28 2000, last modified Oct 21 2004]

Ocean Thermal Energy Conversion http://www.nrel.gov
A fairly complete intro to OTEC, but there is a lot more out there. [ceresian, Jun 28 2000, last modified Oct 04 2004]

International Peaple Shooter The_20Denver_20Inte..._20Peaple_20Shooter
Suborbital-velocity electromagnetic catapult, as mentioned in an annotation [Vernon, Sep 26 2006]

[link]






       I don't know about this. I have this vague holistic concept/belief that every thing on the planet belongs here somehow. ("Conservation of matter/energy and all that" would apply here, too.) What do we do if we need it back for some reason?
etrigan, Jun 28 2000
  

       What if we need rotten banana peels back for some reason? Easy: eat more bananas.   

       "what if i need this piece of trash for some unforseen reason in the future" .......   

       watch it - it's easy to fall into being a pack-rat. :)   

       There has to be a line somewhere between useful and trash. I'm of the persuasion that nuclear waste is trash.
ember, Jun 28 2000
  

       again, conservation of matter. the earth has only so many molecules as it is. if we start tossing everything we don't want into space, aren't we going to find the planet shrinking? how will this affect the tides and the moon? our own orbit? (can incoming meteors/falling stars add enough mass? i think not.) this same concept applies to energy. nuclear waste contains so much potential energy. can we afford to lose it?
etrigan, Jun 28 2000
  

       by the time we figure out how to use the "so much potential energy" in the nucleaar waste, we will have found a way to use the potential energy in the sun, which is infinitely greater.
Omicron, Jun 28 2000
  

       A misunderstanding about nuclear waste is that it has to be separated from the biosphere for many thousands of years. This would be true ONLY if you want ALL the radiation to begone. However, the biosphere is already immersed in what is known as "background radiation", and for most nuclear waste to decay to the same level as the natural background only takes 600 years or so. Therefore the waste only needs to be confined for that long. Next, instead of trying to dispose of it, we should be USING it.. Piling a lot of it together in one special spot is a good idea, because it will generate heat. This heat could be extracted as an energy source, for hundreds of years.
Vernon, Jul 01 2000
  

       So how much energy will be required to launch the "spent" fuel? Perhaps there's the rub.   

       Even if we manage to find a safe way of disposing (or using) the depleted fuels, IMO, there's still the problem that humans require extreme amounts of intense concentration and constant oversight to prevent screw-ups. For example, Commonwealth-Edison, power generator to Illinois and other points in the midwest, has been shutting down reactors because they are unable to safely run nuclear plants.   

       The average joe who works at a reactor or for the contractor who built it just can't seem to hold it together enough day-in and day-out.
johan, Jul 01 2000
  

       I can agree that the heat generated by a huge pile of low-level radwaste is not particularly concentrated. Nevertheless, we have the technology to extract it with reasonable efficiency; the technology has the acronym OTEC, and comes from another field of engineering altogether. Ocean Temperature Energy Conversion relies on the difference in temperature at the top and the bottom of the ocean, to generate energy. I should also mention that the approprate "working fluid" to extract heat from radwaste is helium gas. It is the most inert substance, and that includes resistance to becoming radioactive.
Vernon, Jul 02 2000
  

       You ask why it wouldn't work?   

       First of all, you speak of "magnetic rail guns" as if they're mature, well-developed technology. Have you ever seen one? That's because they don't exist, except as tiny prototypes. We haven't got any that shoot stuff into orbit, let alone at the Sun. So as long as you're talking about dreamworld sci-fi technology, why not start with fusion reactors so we don't have waste in the first place? (Yes, you can find Web sites about railguns and coilguns and all sorts of fantastic ways to get stuff into orbit. That doesn't mean it exists now, and you'll note that nobody's talking about dumping stuff into the Sun.)   

       Secondly, while "leaving it on the ground" isn't very safe, hurtling it through a complex electronic device at miles per second makes Chernobyl look inviting. If even the tiniest thing goes wrong, one of these canisters will rip the machinery to shreds or slam into the ground... probably spreading plutonium all over. You can design a canister to survive almost any imaginable trucking accident at a conventional waste facility; you cannot design one that will survive impact at orbital speeds.   

       Thirdly, the energy required to do this is tremendous. Not only do you have to overcome the Earth's gravity well, you also have to counteract the Earth's own orbital velocity. You also have to add enough speed boost so that air resistance leaving the ground doesn't slow it down too much. And with today's technology, that will require superconducting magnets -- and probably the liquid-helium kind, not the liquid-nitrogen kind. That's a *lot* of energy, perhaps more than was generated to produce the waste in the first place!   

       Finally, even if you had the technology, had somehow put in enough safety precautions, made the energy balance work out and everything else, this would be the most expensive waste disposal strategy ever devised, sufficiently expensive that nuclear power just wouldn't be worth it compared to anything else.   

       "Baked and out of the oven"? I don't think it ever went into the oven.
egnor, Jul 02 2000, last modified Jul 03 2000
  

       I'd have to say that nuclear waste is certainly trash. I haven't done the math, but I suspect that the mass of nuclear energy is not signficant when compared to the earth. Now, if there is a way to reuse it, that's what I'd do too. But there is not, fission isn't winning hearts and minds, and 600 years is much too long for me to monitor anything. Do you expect our information systems to be around then ? What if our databases experiences a burp, and data is lost ? Then we build a housing complex on that stuff and skin starts to fall off people.   

       No thanks. Check out the website, which I found in 10 minutes of searching. Nasa is looking at coil guns (the new version) but I suspect the best of this stuff is trapped by the military. If you think about it, this system I described makes a great Star Wars Weapon as well.
ceresian, Jul 03 2000
  

       I wonder if there is a good reason for almost everything on that railgun site to be _emphasized._   

       egnor: "Thirdly, the energy required to do this is tremendous."   

       etrigan: "nuclear waste contains so much potential energy. can we afford to lose it?"   

       If you use the energy generated by nuclear waste to (somehow) get rid of that waste, is that irony?   

       Larry Niven had a number of proposals:   

       1) Fire cannisters of waste into a lunar crater. I think the seismographs up there are still working...   

       2) Bury it in an ocean trench so that it is pulled back under the crust to heat the mantle.   

       3) Stick it all in one place and surround it with multilingual signs and symbols that say "If you cross this fence, you will die."   

       4) Make it into currency and watch the economic hilarity ensue.
centauri, Jul 03 2000, last modified Jul 04 2000
  

       I find it difficult to believe that anyone would build a housing development on the site of a functioning power plant. We need energy too much to dismantle functioning power plants - - except of course those which are MORE dangerous than existing fission reactors. HAVE you noticed that functioning nuclear fission reactors have tended to be maintained throughout their life-cycle? Since the life cycle of a radwaste power plant would be all those hundreds of years (with major expansions possible as the idea of using nuclear waste may encourage the construction of NEW fission reactors), it seems to me that as long as it functions, a radwaste power plant would be maintained -- and thus off-limits to housing developers.
Vernon, Jul 04 2000, last modified Jul 06 2000
  

       From a Stanislaw Lem story, "Uranium Earpieces": you make currency out of plutonium or U-235, then when your villain (the king in the story, but a certain software tycoon comes to mind) gets rich enough, his hoard undergoes a catastrophic chain reaction.
bookworm, Jul 04 2000
  

       Larry Niven had a short story about the same thing. 'A Modest Proposal: The Roentgen Standard'. Make money out of nuclear waste, as at some point in the future it might be needed. It would keep it in circulation, as collecting too much in any one place would be a Bad Thing; every piece of clothing would have one lead-lined pocket; pickpockets could be spotted by their lack of hair and faintly glowing hands...
StarChaser, Jul 04 2000
  

       centauri - the surrounding of a big pile of nuclear waste with multilingual warning signs is harder than you might think - the warning signs might need to be obvious for 100,000 years and we have a lot of trouble as it is understanding even the most basic works of civilisations which died out only 1000 or 2000 years ago. I think the best 'sign' that the US government has come up with so far is covering the waste dump with about a square mile of nasty-looking spikes.   

       etrigan - don't worry about the conservation of mass - tons and tons of photons get dropped on the earth by the sun every day.   

       Background radiation trivia: Before the first atmospheric A-bomb tests the level of global background radiation was a lot lower. When building equipment for use in synchrotrons and the like, you don't want the equipment itself to be radioactive so they try and make this equipment out of pre-1940's scrap metal. If you can do this without melting the metal, it doesn't become radioactive (apparantly).
hippo, Jul 05 2000
  

       Its possible that it would require too much energy to launch this into space to make this economically feasible. It is also likely that better sources of energy exist than nuclear energy.   

       I am still waiting for the world to run out of oil so we can move to the next energy source. When I was in school, I was told that within 20-30 years I wouldn't be able to buy oil at the market, and there would be dead technology laying all over the world, unusualbe due to the depletion of oil reserves. Unless something changes in the next 15 years, i don't see it.   

       So my mind set is nuclear or die, but after hearing about OTEC I am excited. Solar energy, windmills,etc, are IMO limited, but the ocen temperature differentials looks like a great untapped resource to me.   

       I'll include a link at the top that states the only reason we aren't doing this is economics.   

       Thanks for answering that question !
ceresian, Jul 05 2000
  

       More "background radiation" trivia: Consider the history of Planet Earth, and the fact that all radioactive substances decay. For example, the half-life of Uranium-238 is perhaps 4.5 billion years, about the same age as the Earth. So that means in its early years, there was twice as much U-238 on/in this planet. Thorium-232 has a longer half-life, about 10 billion years, and so way back then there was maybe 1/3 more Th-232 than there is today. And Potassium-40 is mostly gone today; its mere billion-year half-life has led to today's atmosphere consisting of 1% Argon-40. So a billion years ago there was twice as much K-40 as now, two billion years ago there was 4 times as much, and 4 billion years ago there was 16 times as much. I'm pretty sure I need not mention other radioactive isotopes in the same manner (take the 700-million year half-life of U-235 and do your own figuring). The point, is, LIFE EVOLVED IN THE MIDST OF ALL THAT ANCIENT BACKGROUND RADIATION. If it could not have handled it, we wouldn't be here today. (Mad idea: purpose of "introns" in genes is that by making all genes 90% junk, then 90% of the time when radiation strikes, it strikes junk.) Much of today's radiation background is due to cosmic rays, and a noticeable amount is indeed due to the atmospheric nuclear tests of the 1950s. I will continue to maintain that 600-odd years of isolation for radwaste (isolation from the biosphere) will prove to be quite sufficient.
Vernon, Jul 06 2000, last modified Jul 07 2000
  

       If we already have tiny prototype railguns, then perhaps we just need enough of these? We could fire millions of tiny canisters.
kimble, Jul 10 2000
  

       Tiny cannisters would be too small. At the high speed needed to make the cannisters leave the planet, they would burn up in the atmosphere, just like most small meteors do. Only large cannisters can have enough heat-shielding to protect their contents.
Vernon, Jul 10 2000
  

       Unless they don't need to leave the atmosphere - perhaps we could generate a tiny sun. It would orbit the earth at a height of fifty metres (far enough to clear the tops of small buildings).   

       How much gas would I need to form a modest sun?
kimble, Jul 10 2000
  

       Way more burritos than you could reasonably eat, I'm fairly sure.
StarChaser, Jul 11 2000
  

       I'm tempted to accept your challenge, StarChaser... but my mother-in-law is coming round tomorrow, and I promised her it would never happen again.
kimble, Jul 11 2000
  

       Vernon - yeah, 600 years is fine. But to remind you of a point made on this page already, can our society maintain the necessary vigilance to ensure safe containment for 600 years? I don't think so. And as the business of nuclear power production is just that, a business, Mammon will ensure that someday soon a fat man in a pinstripe suit will decide that he doesn't want to spend quite so much time on money maintaining what's essentially a rubbish-heap. Personally, I think that nuclear power is a magnificent solution to the energy crisis, but it scraes the living piss out of me that it's run as a profit-making concern. Profit's short-term. 600 years ain't.   

       And Kimble, start eating those chilli beans, I'll bring the matches.
harquin, Jul 12 2000
  

       I was under the impression that people who like profits also like long-term profits. The proper way to construct a radwaste power plant is in modules. Put one year's waste in one module. After 600-odd years, empty the first module, update its construction, and fill it with that year's radwaste... While we might find it a bit tough today to build low-maintenence modules that can last 600-odd years, what do you suppose we might be able to do that many years from now? Between now and then, we can expect the art to improve, and regular inspections/maintenence/improvements should be required. OK, I know how the money-greedy will try to avoid or buy off inspectors, but the solution to "Who will watch the watchers?" is to have lots of groups of watchers, who watch each other in addition to the things they usually inspect. That will keep the watchers on their toes, who then keep the radwaste power plant operators conducting a safe business. I reiterate that as long as civilization wants power, power plants will be too valuable to go to waste. The worst scenario (other than full scale war) is for terrorists to try to blow up the modules, scattering radwaste everywhere. But that is what we pay security people to prevent (and perhaps why the modules might best be located a modest distance underground. Hey, did you realize that after 50 feet or so, the OTEC heat-collecting technology would be gathering both radwaste and geothermal heat?)
Vernon, Jul 12 2000
  

       600 years from now we won't need to bury this stuff. We'll be eating it.
kimble, Jul 15 2000
  

       This appears to be a dead discussion, but I heard about a method of fusing nuclear waste into a glass block by a sudden jolt of electricity. It had been developed at Brown or some other Eastern University, but I hav'nt heard about it since. Since I live in the state where every one wants to bury their nuclear waste without asking me, I'd appreciate it if anyone who has information on this technique include a link to it here, or email me a rescource (click on my name for my email address).
Scott_D, Aug 02 2000
  

       to quote The 80s band Carnivore, "Nuclear so clean and pure yet its called unsafe not to use it seems a disgrace... like primitive to afraid of fire to exploit its many uses"
Rob C, Dec 13 2002
  

       There IS a way to re-use spent fuel from conventional nuclear reactors. A special type of fission reactor, called a breeder reactor, can use spent fuel from conventional reactors (and breeders can also use U-238, a common type of Uranium that regular reactors cannot use). In this process, it actually produces more fissionable fuel than it consumes. If we were to use the nuclear waste that we have stockpiled right now in breeder reactors, that waste alone would be enough to power the U.S. for 100 years! I would like to note that these reactors are NOT science fiction; they actually have been used in the U.S., Germany, France, Japan, and other countries. The reason they are not too widespread is because (for reasons to complex to give here) they use liquid sodium as a coolant instead of water. This makes it much more dangerous because, should a leak in the plubming occur and the sodium be exposed to air, it would explode and, if near enoguh to the reactor core, possibly set of a nuclear bomblike explosion.
Ahmil, Feb 28 2003
  

       No wonder people are cautioned to monitor their sodium intake.
bristolz, Apr 15 2003
  

       The great thing about this is we are providing fuel for the Sun so it would burn a bit longer before that last final day of wonderful sunlight and then the world get's dark and everybody dies.   

       Also, we brought rocks home from the moon. We could go back and bring lots more moon rocks back and negate the "conservation of energy" problem.
Zorcon, May 17 2003
  

       //we are providing fuel for the Sun//   

       No, we're not (or wouldn't be). The Sun's fuel is hydrogen and helium, and in smaller proportions, lithium and beryllium.
Detly, Jul 11 2004
  

       Could we store nuclear waste for up to, even if not more than, 200 years, in which time we could develop any one of a number of more permanent disposal methods, from safer breeder reactors (actually being looked at by the nuclear power community) all the way to any one of a number of ways to launch the waste into space? If so, maybe we can go ahead almost right now and make more use of nuclear power for those 200 years.
Ponce, Jul 17 2006
  

       Just to address one small part of this discussion: if we did decide that the best ultimate disposal method is shooting the waste into the sun, we wouldn't need a railgun to blast it all the way there. By far the most difficult part of getting anywhere from earth is the first 100 miles into LEO. If you can find a safe way to do this, possibly involving cannisters with multiple-backup parachutes that allow the thing to be recovered safely if there's an accident and it doesn't get into orbit by whatever method you're using, then the next step is easy. Just attach a solar-powered ion drive to the thing, and start firing the engine in a direction that spirals it away from earth and then spiraling into the sun. This will take years, but that's OK--it's already safe, and we just send it all the way to make sure it's never coming back. Ion engines are slow but incredibly efficient so this minimizes our fuel expenses.   

       I wouldn't recommend doing the first step on a rocket or railgun though, a space elevator or rotating tether would be safer and far cheaper, if we can make either of those work.
scottinmn, Sep 25 2006
  

       [21 Quest], that's the wrong problem, that you have pointed out. In terms of actual energy, when efficiently applied, it is reasonably inexpensive to put a kilogram of mass into space. But rockets are woefully inefficient, and so they use lots and lots more energy than a railgun would use. However, a railgun would sit at the bottom of the Earth's atmosphere, and that's the main problem. Think "meteor" and "sonic boom" as a kilogram of mass plows through the lower atmosphere at thousands of kilometers per hour, on its way to Space, after having left the railgun. The projectile would have to have been accelerated to an even more extreme speed, to make up for the energy it would lose, plowing through air on its way to Space. At least rockets don't get up to such speeds before they have climbed above most of the atmosphere.   

       The alternative is the mountain-climbing electromagnetic catapult. See link.
Vernon, Sep 26 2006
  

       If you want to get to the sun with this, you'll have to accelerate the canister to the earth's orbital speed around the sun, or 18.5 miles/s. That's 4 times the speed just to orbit the earth, and 16 times the energy. Of course, the speed has to be higher than that to compensate for atmospheric drag and the earth's gravity. So let's say 25 miles/s (Mach 118) as it leaves the gun.

Unfortunately, if you miss the sun, the canister will go into a highly eccentric orbit, just touching earth's orbit. So every once in a while, one of these things will come back.
ldischler, Sep 26 2006
  
      
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