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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 !
(?) 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]
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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? |
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What if we need rotten banana peels back for some reason? Easy: eat more bananas. |
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"what if i need this piece of trash for some unforseen reason in the future" ....... |
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watch it - it's easy to fall into being a pack-rat. :) |
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There has to be a line somewhere between useful and trash. I'm of the persuasion that nuclear waste is trash. |
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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? |
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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. |
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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. |
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So how much energy will be required to launch the "spent" fuel? Perhaps there's the rub. |
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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. |
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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. |
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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. |
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You ask why it wouldn't work? |
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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.) |
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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. |
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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! |
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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. |
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"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 |
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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. |
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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. |
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I wonder if there is a good reason for almost everything on that railgun site to be _emphasized._ |
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egnor: "Thirdly, the energy required to do this is tremendous." |
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etrigan: "nuclear waste contains so much potential energy. can we afford to lose it?" |
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If you use the energy generated by nuclear waste to (somehow) get rid of that waste, is that irony? |
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Larry Niven had a number of proposals: |
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1) Fire cannisters of waste into a lunar crater. I think the seismographs up there are still working... |
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2) Bury it in an ocean trench so that it is pulled back under the crust to heat the mantle. |
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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." |
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4) Make it into currency and watch the economic hilarity ensue.| — | centauri,
Jul 03 2000, last modified Jul 04 2000 |
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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 |
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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. |
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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... |
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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. |
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etrigan - don't worry about the conservation of mass - tons and tons of photons get dropped on the earth by the sun every day. |
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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). |
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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. |
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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. |
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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. |
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I'll include a link at the top that states the only reason we aren't doing this is economics. |
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Thanks for answering that question ! |
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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 |
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If we already have tiny prototype railguns, then perhaps we just need enough of these? We could fire millions of tiny canisters. |
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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. |
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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). |
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How much gas would I need to form a modest sun? |
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Way more burritos than you could reasonably eat, I'm fairly sure. |
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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. |
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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. |
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And Kimble, start eating those chilli beans, I'll bring the matches. |
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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?) |
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600 years from now we won't need to bury this stuff. We'll be eating it. |
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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). |
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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" |
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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. |
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No wonder people are cautioned to monitor their sodium intake. |
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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. |
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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. |
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//we are providing fuel for the Sun// |
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No, we're not (or wouldn't be). The Sun's fuel is hydrogen and helium, and in smaller proportions, lithium and beryllium. |
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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. |
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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. |
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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. |
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[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. |
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The alternative is the mountain-climbing electromagnetic catapult. See link. |
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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. |
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