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Zapping Nuclear Waste in Minutes Is Nobel Winner’s Holy Grail Quest
- saagarjha 7y ago> The idea is to transmute this nuclear waste into new forms of atoms which don’t have the problem of radioactivity. What you have to do is to change the makeup of the nucleus. Ok, but what exactly is it transmuting the atom to?
- mimixco 7y agoRadioactive materials are dangerous because their subatomic makeup is unstable, meaning they emit dangerous particles as the atom degrades from the inside. So it would seem that, in order to fix that, you'd have to re-populate the innards of the atom with enough protons to make it stable again. It's worth noting that transmutation is definitely possible. The alchemists of old would be thrilled to know that we can, in fact, make gold from base metals (in a nuclear reactor). The problem with that is that the cost of doing so is worth more than the gold could be sold for.
- Armisael16 7y agoThat didn't answer the question asked at all.
- saagarjha 7y agoI know how radioactivity and transmutation works; my problem is that I don't actually know how this problem is being "solved".
- mimixco 7y agoNeither does the guy who proposed it, lol!
- Someone 7y agoI also wonder about that. If it transmutes into the natural decay products, energy must come out, and, depending on the size of that laser/proton gun, we could (although I think that’s highly unlikely) even be talking about a way to make small nuclear bombs. Also, will the end result still be energy positive? Even if the transmutation doesn’t add energy to the nucleus, that can be problematic, as that laser will need to be powered. And of course, there’s the question of ‘aim’: can we really target individual atoms well enough to ‘hit’ them exactly once? (this might be fairly easy if the process requires specific energies that the radioactive atoms, once ‘hit’ no longer are sensitive to)
- jayalpha 7y agoWell, other atoms? Depending where you start from and how do it. Here is an example: http://www.ipodphysics.com/resources/trans90.jpg http://www.ipodphysics.com/resources/trans90.jpg
- saagarjha 7y agoThat's my question: I don't know which way they're moving.
- petre 7y agoIt depends on the decay mode. Through beta decay they usually go up (eg. Cs135 › Ba135) one spot in the periodic table (straight line in the diagram). Through alpha decay they go down as shown in the diagram. What the diagram represents is natural decay of Uranium which isn't "waste". The long lived fission products in the GP link are more or less of an issue.
- rocqua 7y agoI think the best option would be to accelerate the decay. That should be relatively easy (i.e. has a net energy output) and massively reduces the radioactivity.
- saagarjha 7y agoAccelerating the decay would increase the radioactivity, at least until you've reached something with a long half-life.
- rcxdude 7y agoYes, but short-term high-radioactivity material is easy to do with, as is the super-long term low radioactivity material. The problem is the stuff in the middle which has a long enough half life that it's hard to store safely for that long but enough radioactivity to be dangerous. So if you can turn that stuff into either of the previous two catagories it's a win.
- credit_guy 7y agoLet's take an example. Here's the list of the 7 long-lived fission products [1]. The nastiest appears to be Caesium-135 [2]. If you zap this with a proton it becomes Barium-136, which is a stable element (the half-life is so long that it cannot be estimated; probably it is in the trillions of years). [1] https://en.wikipedia.org/wiki/Long-lived_fission_product#The_7_long-lived_fission_products https://en.wikipedia.org/wiki/Long-lived_fission_product#The... [2] https://en.wikipedia.org/wiki/Isotopes_of_caesium#Caesium-135 https://en.wikipedia.org/wiki/Isotopes_of_caesium#Caesium-13...
- mschuster91 7y ago> Mourou and Tajima want to create a high-speed laser-driven accelerator to produce a beam of protons that can penetrate atoms. Is it only me who is reminded of Iron Man 2 and the new element created by that hacked together accelerator in Tony Stark's basement? As for the topic of the article: I would really find it interesting how much "bandwidth" (=kg/day) such a setup has and what the energy requirements are. If the process consumes more than half the energy that the fission process generated, is it still profitable then? Also, what are the byproducts? I can't really believe that this leaves stable lead and other things only behind.
- chmaynard 7y agoThis is another of many "silver bullet" proposals to reverse the environmental damage caused by Western civilization. Most of they won't work and will have unintended consequences. As always, prevention is the best cure.
- mises 7y agoOnly by Western civilization? China is the largest polluter; India is third. The West may not be blameless, but it is not solely the fault thereof. What is your better idea, now that the time for prevention has passed?
- mschuster91 7y agoYeah but most nuclear waste came from the US, UK, France and Russia. As for a better idea, molten salt/thorium reactors, they can eat at least the highly dangerous/ultra long half life stuff.
- acidburnNSA 7y agoFast neutron reactors can. Most thorium MSRs are slow neutron reactors and struggle to transmute significant used nuclear fuel.
- arcticbull 7y agoMy understanding is that Thorium reactors are far less likely to produce transuranic elements with long half-lives, and less waste in general (two order of magnitude). [1] However, it does in fact require some fissile material such as recycled plutonium, so the two reactor kinds can work in conjunction to yield a net drop in long-half-life nuclear wastes. [2] [1] https://en.wikipedia.org/wiki/Thorium-based_nuclear_power https://en.wikipedia.org/wiki/Thorium-based_nuclear_power [2] http://www.world-nuclear.org/information-library/current-and-future-generation/thorium.aspx http://www.world-nuclear.org/information-library/current-and...
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- mimixco 7y agoNuclear energy has its advocates—it spews little by way of emissions and is produced relatively cheaply. Nuclear is anything but cheap. It's a net negative energy source, meaning the the electricity costs more to produce than it can be sold for. This is why the industry requires massive subsidies to stay alive. (If I recall correctly, the last round of subsidy in the US was over $50 billion.) Nuclear power also requires massive amounts of carbon, as the uranium fuel must be mined and extensively processed before it is useful. The mining and milling process is horribly polluting and has ruined the land and water in many places on Earth. Now, having said that, I certainly hope this guy can come up with a way to transmute radioactive elements with lasers. That would be terrific. But I'm doubtful.
- graeme 7y agoGot a source? I'd read the EROI of nuclear is quite high.
- mimixco 7y agoThe simplest source is the closure of many existing nuclear plants and the cancellation of all but one which we're planned for the US. It's not well known that the industry requires billions in government subsidies to even exist today. If taxpayers are footing the bill, that tells you that selling electricity isn't paying its own way. Fewer people still know that nuclear plants are uninsurable, for somewhat obvious reasons. Government insurance for nuclear accidents is another huge subsidy that shows the industry isn't viable on its own. For more info, see Helen Caldicott's excellent book, Nuclear Power is Not the Answer.
- arcticbull 7y agoIt's as likely they were cancelled due to negative public sentiment towards nuclear energy. We're going to need some sources.
- mimixco 7y agoGoogle is your friend! Only one nuke plant in the US was shut down over protests (San Onofre) and that took 20 years. The press releases from plant owners who closed or cancelled their plans all cite negative economics as the reason.
- xanth 7y agoI wonder how much this processes would consume and further reduce the effective yield.
- turbohz 7y agoEnergy from other sources, such as renewals could be used. The disposal could be scheduled when those are generated in excess.
- xanth 7y agoGood point, even with non renewable resources excess power is often entirety wasted when the expected grid consumption is lower than the production.
- nickik 7y agoOr we could just use that valuable fuel and put it into nuclear reactors to make energy and other useful stuff. But that seem to be a totally crazy idea.
- mimixco 7y agoReprocessing is its own nightmare and, I think, only France tries to do it. All of these processes (the "uranium cycle") are terribly polluting in their waste outputs and dangerous places for the people who have to work there and live near them.
- garmaine 7y agoWhat nightmare? Reprocessing is a net cleanup compared with letting the waste sit. I have some nuclear engineering background and honestly I don’t know what you’re referring to.
- mimixco 7y agoReprocessing isn't clean. It creates its own waste which is worse than the spent fuel you started out with. Reprocessing plants (like every part of the uranium cycle) are dangerous places to work and live near.
- garmaine 7y agoIt creates a lot less waste, which is the point. Lots of fuel (waste) in, little bit of waste out.
- benzofuran 7y agoIt's like the US doesn't already have a number of remote areas like Hanford, Oak Ridge, Idaho Falls, the Savannah River Site, Rocky Flats, etc. that are already set up (and somewhat contaminated already) for handling this sort of material and process. In reality it's a political nightmare, not a pollution one.
- nl 7y agoYour periodic reminder that - despite the propaganda campaign run by nuclear advocates to make it seem like being anti-nuclear is to be anti-science - nuclear power remains massively expensive and even less safe than people think. Here's the most comprehensive peer-reviewed survey around: We summarize the results of a recent statistical analysis of 216 nuclear energy accidents and incidents (events). The dataset is twice as large as the previous best available. We employ cost in US dollars as a severity measure to facilitate the comparison of different types and sizes of events, a method more complete and consistent that the industry-standard approach. Despite significant reforms following past disasters, we estimate that, with 388 reactors in operation, there is a 50% chance that a Fukushima event (or more costly) occurs every 60–150 years. We also find that the average cost of events per year is around the cost of the construction of a new plant. This dire outlook necessitates post-Fukushima reforms that will truly minimize extreme nuclear power risks. Nuclear power accidents are decreasing in frequency, but increasing in severity. https://www.sciencedirect.com/science/article/pii/S2214629615301067?via%3Dihub https://www.sciencedirect.com/science/article/pii/S221462961...
- Consultant32452 7y agoHow many Fukushimas will we (society) accept every 150 years in order to stop climate change? That's really the only question that matters.
- c1sc0 7y agoBoth Fukushima & Chernobyl would have been essentially non-issues if built further away from population centers. I know this is Sim City logic: but my answer to that would be: quite a lot!
- croh 7y agois there a way to zap plastic waste in minutes ?
- gambiting 7y agoYes - you can burn it for energy, which is already done in many countries. With good enough filters it's the best solution to plastic waste that we have.
- m0llusk 7y agoThere are multiple ways. Grinding it up and then using a plasma furnace to break down the molecules is a proven way to reduce a waste stream to component elements.
- hairytrog 7y agoSpent nuclear fuel, sometimes called waste, is actually a resource that next generation reactors will be able to tap - both for energy and uncommon element feedstock. Just like shale used to be "garbage" until the tech to make it useful was developed, spent fuel will be seen as waste until we can make it useful. Letting this very manageable amount of waste sit in repositories until we get our shit together is utterly reasonable. In the US, it would take just one facility to deal with all 99 reactor waste streams. I don't think we need to spend money and energy to transmute it by theses questionable laser schemes. Accelerator driven transmutation of waste was shown the dustbin a few decades ago, hopefully this will have the same fate. Please don't ruin our valuable trash.
- carlosdp 7y agoDon't even centralize it all in one facility, just store it on-site.
- caymanjim 7y agoThat's how most of the power plant waste in the US is "handled" right now, because it's so far been politically impossible to agree on long-term storage and transportation. It's an inferior solution, though. There are security issues, and many points of failure for environmental damage. It's particularly problematic when plants are decommissioned and the waste is still stuck there requiring indefinite security and storage facilities for an otherwise-defunct plant. We'd be better off with all of it in one secure and safe facility, pending a better solution in the future.
- mort96 7y agoHow would one transport the waste across the country? I imagine there are some security issues with that too.
- joering2 7y agoVery easily these days [1] Its been done since days of nuclear plants. And no - there are no security issues, since as the name indicates, its a “waste”; you can’t make a bomb out of it and spreading it would not be as efficient as some type of gas that you would have easier access to. I imagine actually officials would love just to give away that nuclear waste to ISIS, preferrably deliver it to them for further handling by their peers, without gloves of course ;) http://nuclearconnect.org/know-nuclear/technology/nuclear-waste http://nuclearconnect.org/know-nuclear/technology/nuclear-wa...
- a1e2c3 7y ago“A radionuclide is an atom that has excess nuclear energy, making it unstable.” This seemed like a vague definition, didn’t sit well with my memory of high school chemistry and physics. Turns out it’s the first sentence on Wikipedia: https://en.m.wikipedia.org/wiki/Radionuclide https://en.m.wikipedia.org/wiki/Radionuclide Someone at Bloomberg got a little lazy.
- mrpara 7y agoIt's accurate and not really vague at all, it's just not highschool level physics. I'll try to explain it in layman terms. Imagine that you have a bunch of free particles that are not connected to each other in any way, and are far enough from each other that any interaction between them (such as electromagnetic fields) is negligible. Ignoring their own masses, the energy of the system is zero. Now imagine these same particles, bound together into a single atom. Obviously, for the atom to be stable, you don't want it to be able to fall apart on a whim. You want a system where you have to input a lot of energy for the atom to fall apart. But as we just said, the state where the constituent particles are separate is the default, zero-energy state. Therefore, a stable state where you have to add energy to reach the default free state must actually have negative energy! To be specific, the binding energy is negative while the energy related to the mass of the particles, i.e. e=mc2, is positive. The atom is actually lighter than the sum of its parts! An atom that doesn't have negative binding energy, i.e. has "excess energy", has nothing binding the constituent particles together, since they have more than enough energy to go run free on their own. Therefore it is unstable. Elements with a small enough binding energy, small enough that random fluctuations can overcome it and make the atoms fall apart, are what we call radioactive elements.
- hokus 7y agohere you go https://www.youtube.com/watch?v=1R5G5hTC7pc https://www.youtube.com/watch?v=1R5G5hTC7pc next quest
- credit_guy 7y agoThey had me at Cedric Villani "For Cedric Villani, a French lawmaker and the winner of the Fields Medal—the Nobel Prize equivalent for mathematics—that’s no reason to give up. “What Mourou is really after is the accelerator that the laser creates,” he said. “It’s far-off, but why not?” "
- 08-15 7y agoA ridiculous idea. The article doesn't go into technical details, but it appears this boils down to a compact proton accelerator. Those protons could be smashed into heavy metal atoms, which will release high energy neutrons. Those neutrons could in turn be used to irradiate nuclear waste, transmuting it. The first problem with that idea is that stable atoms would be transmuted, too. So unless the waste is separated chemically (aka reprocessed), irradiating it with neutrons tends to make matters worse. In some cases, notable cesium, isotopic separation seems necessary. But if you assume reprocessing, you might as well stuff the components to be irradiated into a reactor, where the actinides act as fuel and some waste products will transmute away. The second problem is the ridiculously low efficiency of such an accelerator system. Carlo Rubbia has been talking about the concept (ADS, Accelerator Driven System, also called Energy Amplifier) for something like 20 years, and even he only envisions supplying comparatively few neutrons to a subcritical reactor. But a barely subcritical reactor isn't all that different from a critical reactor, except you can turn it off by turning off the accelerator instead of by moving a control rod. In short, this is another guy with a solution (the accelerator) looking for a suitable problem. (For the record, continuous recycling of actinides is a good idea that turns "the waste problem" from an unsolvable million-year problem into a manageable 500 year problem. Transmutation of iodine and technetium may be a good idea, too, because these are the only long term radionuclides that would leach into water.) Edit: names are difficult
- amai 7y agoDoesn't that need more energy than you generated out of the material in the first place?
- admax88q 7y agoI wonder what our attitude towards landfills would be if they were described the same way that nuclear waste storage facilities are. > no country can claim to have a comprehensive solution for dealing with its toxic waste. > more than 60 years after getting into nuclear energy, [France] still has no definitive way to cope with it. Sentences like these imply that there's dangerous waste just sitting sitting around while officials scratch their heads about what to do. We do have comprehensive solutions. We build giant concrete wells and just put the waste there, problem solved. This solution seems to be accepted as reasonable for garbage via landfills, but for nuclear waste its somehow treated as a workaround until we find some other magical way to get rid of it.
- sfink 7y agotl;dr - scientist proposes solution to the nuclear waste problem: alchemy. With lasers.