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Fusion-Fission System Burns Hot Radioactive Waste 432

An anonymous reader writes "A hybrid fission-fusion process has been developed that can be used in some traditional fission reactors to process radioactive waste and reduce the amount of waste produced by 99%. This process uses magnetic bottle techniques developed from fusion research. This seems like the first viable solution to the radioactive waste problem of traditional nuclear reactors. This could be a big breakthrough in the search for environmentally friendly energy sources. Lots of work remains to take the concept to an engineering prototype and then to a production reactor."
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Fusion-Fission System Burns Hot Radioactive Waste

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  • by 0100010001010011 ( 652467 ) on Friday January 30, 2009 @11:30AM (#26666649)

    If at any point in this process (say you stop it at 50%) the 'waste' is now weapons grade this will never be allowed in the US.

    If it's still 'radioactive' you can still get energy from it. You can refine it, clean it up and shove it back through again.

    Generations ago we were masters of waste not want not. If you burned candles for light, you collected your drippings, remelted them into new candles. Imagine if the 13 Colonies outlawed this because you could also remelt them into canon wicks... absolute stupidity.

    • by SatanicPuppy ( 611928 ) * <> on Friday January 30, 2009 @11:36AM (#26666727) Journal

      I RTFA, but I'm still a bit snowjobbed because it's pretty light on detail.

      It seems like their touting the solution primarily as a way to reduce transuranic waste (sludge). There were no numbers based on how much more or less energy this process would produce.

      It's my understanding that re-enrichment is more about separating undepleted U-235 from depleted U-238, so I have no idea what reducing transuranic sludge would have to do with this. It might increase the (relative) percentage of U-235 enough to keep the fission reaction going, or it might just make the reaction slightly cleaner.

      • by goombah99 ( 560566 ) on Friday January 30, 2009 @12:10PM (#26667173)

        I'm also guess here. A decade ago, Los Alamos pioneered Accelerator Transmutation of Waste. There the idea was you bombard high level waste with a particle beam to, ironically, make it even higher level waste. The clever thing was this. The higher the radioactivity the shorter the half life.

        The plan was to convert things with halflifes of 50,000 years to half lifes of hours. An insanely clever idea. But it never got much funding.

        I'm guessing that this Fission/fussion system is probably playing the same game. Fusion makes for heavier nuclii, which if they are not stable, tend to be even short lived as a general trend.

        • by jhfry ( 829244 )

          My god man... a sensable explanation that doesn't require a PHD in physics. This site isn't what it used to be!

          MOD parent up.... and find more like him.

        • by FTWinston ( 1332785 ) on Friday January 30, 2009 @01:04PM (#26668035) Homepage
          The fusion will be of lighter nuclei; deuterium or helium probably. They won't be fusing the 'sludge' or anything heavy that; that would take more energy than it would produce (thats why stars stop fusing at iron).

          The fusion of the lighter nuclei will produce a lot of neutrons, their idea being to bombard the 'sludge' with neutrons to cause its nuclei to destabilise and fiss apart. Its kinda win-win really: the fusion reaction won't be terribly efficient, and on its own would probably produce only about as much energy as it takes to sustain it, but the fissing of the heavy nuclei will release a bunch more.
        • Re: (Score:3, Interesting)

          by Firethorn ( 177587 )

          As a byproduct, of course, the decay produces a huge amount of heat, easily enough to feed a steam turbine to power the beam and other stuff.

          I wish the article had mentioned something about it's energy generation capabilities. By the sounds of it, it probably doesn't process 'raw' waste out of cores, instead treating the waste resulting from reprocessing them to sort out the still usable fuel elements.

          I'm still for using breeder reactors.

      • Re: (Score:3, Informative)

        I RTFA, but I'm still a bit snowjobbed because it's pretty light on detail.

        There are more details at the following links: [] []

    • Thinking about it further, weapons grade waste is almost all transuranic (e.g. plutonium), so if the purpose of this is to reduce that, then there should be less weapons grade waste, not more.

      If it's actually using that plutonium to sustain it's reaction, and produce more energy, it would seem like a good solution.

    • by Shakrai ( 717556 ) on Friday January 30, 2009 @11:57AM (#26667019) Journal

      If at any point in this process (say you stop it at 50%) the 'waste' is now weapons grade this will never be allowed in the US.

      That's the dumbest fucking policy we've ever come up with and yet another reason that Jimmy Carter ranks up there with worst Presidents we've ever had. How does preventing our own country from reprocessing spent nuclear fuel do a damn thing to prevent nuclear proliferation? Other countries can (and indeed do) pursue reprocessing. We've handicapped ourselves for zero gain as far as I can see. Thanks a lot Mr. Carter.

      <sarcasm>But at least we've stopped GE and Westinghouse from going rouge and building their own nuclear arsenals</sarcasm>

    • Re: (Score:3, Informative)

      by Ihlosi ( 895663 )

      If at any point in this process (say you stop it at 50%) the 'waste' is now weapons grade this will never be allowed in the US.

      Producing weapons-grade enrichment (as in "can be used to build nuke") is _frikkin'_ expensive. You don't do that unless you _want_ to build a nuke, since it's a waste of money for any other purpose.

      If it's still 'radioactive' you can still get energy from it. You can refine it, clean it up and shove it back through again.

      Radioactivity is not a criterion for a nuclear fuel used in

    • by inviolet ( 797804 ) <> on Friday January 30, 2009 @12:24PM (#26667385) Journal

      Generations ago we were masters of waste not want not. If you burned candles for light, you collected your drippings, remelted them into new candles.

      That was the consequence of materials costing more than manhours. Now thanks to industrialization and automation, manhours are vastly more expensive than material, simply because one manhour produces 1000x more material than it did before. (In the grand scheme of things, the cost of either is a function of its exchange rate with the other.)

      Our allegedly wasteful modern society is wasteful of the visible component (material) because it is so careful to conserve the invisible component (manhours). Unfortunately most people are concrete-bound and so do not understand what's going on.

      Imagine if the 13 Colonies outlawed this because you could also remelt them into canon wicks... absolute stupidity.


      • Re: (Score:3, Insightful)

        by localman ( 111171 )

        I sense there's some hand waving going on here because some materials are finite while manhours are not. Yes, I'm playing fast and loose with the term "finite", but I think the point stands. All the manhours in the world won't be worth much when we run out of some critical resource. At which point manhours suddenly become finite too, if you understand my meaning.

        Unfortunately most people don't see a distinction between "more than I can imagine" and "infinite". Thus we have no need to worry about our atm

    • > If at any point in this process (say you stop it at 50%) the 'waste' is now weapons grade this will never be allowed in the US. You mean: it'll be allowed in the US, built by the lowest-bidding contractor, with security run by the most well-connected bureaucrat, and we'll bomb or sanction any other country that tries to build one as a terrririst thret.
    • sometimes being modded up to only +5 just isn't enough.

  • One small hitch... (Score:5, Interesting)

    by Muad'Dave ( 255648 ) on Friday January 30, 2009 @11:31AM (#26666669) Homepage

    First, they have to get sustainable fusion working, then they can installed the Super-X Divertor to bleed off neutrons to burn fission waste.

    Why not use safe, proven technology [] available TODAY to burn 99% of current fuel AND WASTE?

    • Re: (Score:3, Insightful)

      by robot_love ( 1089921 )
      I've read that article several times before, and it always makes me depressed. How come I can't shake the feeling we'll doom ourselves slowly with petroleum usage rather than attempt a reactor like the article outlines?
      • by silas_moeckel ( 234313 ) <silas&dsminc-corp,com> on Friday January 30, 2009 @12:20PM (#26667323) Homepage

        Because the eco lobby does not like it and will scare monger anything to do with it. Grandma thinks that a reactor failing will look like Hiroshima.

        Unfortunately people can not get it through there heads that fission/fusion is the only sustainable method of energy generation that can deal the increasing demand. Demand will not decrease, this would mean your children will have a lower standard of living than you.

        • by ryanov ( 193048 )

          Have you not read anything about failed reactors? I have, and let me tell you -- it scares the shit out of me.

          • Re: (Score:3, Informative)

            Why? We have had what two failed reactors of note and together they put out far less radioactive anything than coal power plants. You seem to be scared and scared irrational fear has no place in decision making. Would I want to walk into one? No I also would not want to walk into the bottom of a coal power plants smoke stack. Nothing is perfect fission has it's risks but it's the least risky solution that does not involve reductions in living standards. In the modern world that might not seem to bad b

        • by KevinIsOwn ( 618900 ) <herrkevin@gm[ ].com ['ail' in gap]> on Friday January 30, 2009 @02:18PM (#26669073) Homepage
          Don't blame this on the "eco lobby". The ever-powerful eco-lobby that can't even get us to limit carbon emissions barely has the power to stop nuclear power plants. Many environmentalists, like myself, support nuclear power when it's properly regulated and well thought out. The problem is too many people can't get Chernobyl and 3 mile island out of their heads, despite the fact that the pollution from coal and oil is ultimately more destructive than nuclear power.

          The solution is to educate people about the pros and cons, and reasonable people will start siding with nuclear. (Of course, whether or not people are reasonable is another question entirely...)
          • by MaxwellEdison ( 1368785 ) on Friday January 30, 2009 @03:32PM (#26670201)
            I lived in the same township as Three Mile Island for about 10 years. Also, my National Guard unit was tasked with providing an additional security presence in the months following 9/11. Anyone who wants to say anything about the horrible environmental impact of nuclear energy need only visit the southern 2 miles of the island (don't actually try to'll get arrested and possibly shot a bunch). It is as off-limits and protected as the rest of the facility, and is covered in wildlife, including more deer than I have seen anywhere else in my life. It's a nice area, plenty of good farm land, and not a single three eyed fish to be found. Be gone with your fear fueled rhetoric against nuclear power. I'll take one in my back yard before a fossil fuel plant any day.
        • Re: (Score:3, Interesting)

          by bitrex ( 859228 )

          The anti-nuclear lobby has nowhere near the kind of clout that you seem to attribute to it. I can think of only 1 reactor project off the top of my head in the United States that was canceled due to environmentalist pressure (the Shoreham plant on Long Island).

          It's often claimed that Three Mile Island was the catalyst that caused the eco lobby to sink nuclear power projects in the United States. What's not often mentioned is that power companies and their investors took a hard look at nuclear power after

          • Re: (Score:3, Insightful)

            by tsotha ( 720379 )
            The majority of nuclear plants that have been canceled over the past 20 years have been canceled not because of environmentalist pressure, but simply because the ROI wasn't there. Yes, and the ROI wasn't there because of all the extra cost and delays put in place... by the anti-nuclear lobby. Why is it the Europeans seem to be able to do this but in the US the ROI isn't there?
    • by Knightman ( 142928 ) on Friday January 30, 2009 @11:53AM (#26666941)

      You know there is no problem sustaining a fusion reaction with todays tech, the problem is sustaining a fusion reaction that has a net surplus of energy.

      There are even tabletop fusionreactors that are used as a source of neutrons.

      The point of this tech is to scale the fusionreactor up so you get alot of neutrons to bombard the sludge, the fusion doesn't need to generate any energy.

      • Re: (Score:3, Interesting)

        by Muad'Dave ( 255648 )

        A couple of questions.

        1) Are current fusion reactors able to provide the necessary neutron flux to assist a fission reactor in burning this waste?

        2) Is the energy generated by the boosted fission enough to power the fusion reactor if you don't have the luxury of a self-sustaining fusion reactor?

        If either answer is no, I'd rather see IFR technology put into place starting now than wait for this to become feasible.

        • by Retric ( 704075 ) on Friday January 30, 2009 @01:05PM (#26668039)

          1) Yes.
          2) Yes.

          We can build stable, multi-Megawatt Fusion reactors that are close to break even. The basic idea is used by H-bomb's. They use the high neutron flux from fusion to increase fission yield. One of the basic fission problems is it becomes hard to have a stable reaction as you scale things up. You can use lot's of crappy fuel in a huge mound, but you have little control over what that pile is going to do. And as you burn fuel you change the nature of the fuel in such a way that it becomes even harder to maintain stability. If you can have a fixed source of neutron that feeds the pile you can setup a multiplier where 1 neutron in produces X reactions, but it's not self sustaining so it can't get out of control.

          PS: Breeder reactors are far less stable than non breeder reactors. Think of a traditional oil lamp filled with gasoline. With with great care it can work, but it's just not as stable as heavy oil.

    • by Andy Dodd ( 701 )

      As to sustainable fusion - Sustainable fusion for the purposes of directly generating energy, where the energy output of the process is more than the energy in, is difficult and years away from being achieved.

      Sustainable fusion for the purposes of generating neutrons (albeit at a net energy loss) is already here - look up the Farnsworth Fusor. Can't create energy but is routinely used as a neutron source.

      I've always wondered if you couldn't solve the breakeven problem with a hybrid approach like this - a c

  • by SpuriousLogic ( 1183411 ) on Friday January 30, 2009 @11:32AM (#26666687)
    Scientific American just had an article on fast neutron reactors that get around the waste issue and don't create any weapons grade material: []
    • by Muad'Dave ( 255648 ) on Friday January 30, 2009 @11:58AM (#26667025) Homepage

      Amen. That article was a reprint from Dec. 2005, IIRC.

      Here a link [] to a QA session regarding AFR/IFR technology. It irks me to no end that ignorant, short-sighted politicians quashed this technology 15 YEARS AGO, and the greenies have taken that long to get over the "my god, it's nucular!" fearmongering and actually start to embrace it as an environmentally-safe alternative to our current mess.

    • by Kupfernigk ( 1190345 ) on Friday January 30, 2009 @12:17PM (#26667277)
      Fast breeder reactors turn out not to be as easy to make safe and reliable as their proponents think. Google for more recent literature. It's a pity, I personally like the idea, but both fast reactors and fuel reprocessing have turned out to be very difficult.
    • Yes, the technology was shot down in 1994 by our brilliant government. Lets hope this line of research is brought back so that we can both increase energy output and reduce harmful wastes.
  • Keep wishing... (Score:2, Insightful)

    by sac13 ( 870194 )

    There's never going to be an energy source that will be environmentally friendly enough for the people that think nuclear is too dirty now. Should coal and nuclear be replaced with solar, wind and/or wave generation, these same people will begin complaining about the negative effects of removing energy from the environment with those methods, wildlife being killed in wind/wave farms or whatever other impact can be identified.

    The fact will always remain that life, regardless of humanity or other life, impac

  • Neat technology (Score:5, Insightful)

    by ShooterNeo ( 555040 ) on Friday January 30, 2009 @11:41AM (#26666787)

    This is neat technology, and may some day be practical. But, i don't think that day is coming for 50-100 years.

    Here's why : solar is getting cheap very rapidly. Today, you can pick up panels at $2.85 a watt off the shelf. Below $1 a watt, and it will be cheaper to put panels up than it will be to burn coal.

    A fusion-fission hybrid system will cost a LOT. According to the wall street journal, nuclear fission plants are already deal-breaker expensive. It would be cheaper per watt to build more wind farms than new fission reactors. []

    Another way to look at it :

                    To operate a fusion-fission hybrid system, as well as dozens of large gigawatt fission reactors takes a lot of well trained and educated people working round the clock to make all of the technology work. There are very real dangers, and very expensive regulations that have to be followed.

                  To build more solar panels? You print some more off the reel and slap them on to glass. You park the panels in the desert and leave them alone for 25 years. Maybe a simple robot wipes them off occasionally.

                  There's no liability, or need for exhaustive quality control. If a panel fails prematurely, you pay a warranty claim.

                Inherently, solar is going to always be cheaper for the foreseeable future.

    • Re:Neat technology (Score:5, Interesting)

      by Broken scope ( 973885 ) on Friday January 30, 2009 @11:46AM (#26666847) Homepage
      How much does the battery system cost?
      • The battery tech isn't available today. You'd need a giant bank of flywheels or some other tech that isn't being mass produced as of right now.
      • Also, if we develop the battery tech for powering electric cars, we would solve the night problem as a side benefit.
    • To build more solar panels? You print some more off the reel and slap them on to glass. You park the panels in the desert and leave them alone for 25 years. Maybe a simple robot wipes them off occasionally.

      There's no liability, or need for exhaustive quality control. If a panel fails prematurely, you pay a warranty claim.

      Inherently, solar is going to always be cheaper for the foreseeable future.

      You miss one important thing that most people do and that's the powergrid today can't utilize solarpower efficiently. The grid is built for steady generation and steady consumption. To be able to use solar power effeciently you have to build energystorages where the surplus are stored during daytime and then discharged during night. This costs money.

      It's basicly the same with any source of energy that has an output that's intermittent.

      The good thing about solar/wind/wave etc. is that we can use it to lessen

      • The good thing about solar/wind/wave etc. is that we can use it to lessen the need for more nuclear/coal energy, but even easier is to use less energy.

        Define 'easier' please?

        Because right now, the market's actions indicate that it is ea$ier to build more powerplants than it is to use less energy.

      • What you are saying is pretty much what the parent said: no need for new nuclear power because everything else costs less.

        When 70% of the coal plants are shut down because solar and wind have put them out of business, will we be looking for something even more expensive than coal? No, we'll just pick up the tab for the loan guarantees for a few new nukes as tax payers and never finish construction, just like in the eighties.
    • It is an interesting technology, but lets be realistic here.

      Building an existing 'off the shelf' LWR design requires roughly 10 years. Turning this technology into a standardized design which can be used by industry will require some amount of time, probably 10-20 years by the time all the safety engineering is complete and a prototype reactor is built, run for several years, and the bugs are worked out of it.

      So, we're talking about OPTIMISTICALLY 2028 and possibly 2038-2048 before the first one of these re

    • Below $1 a watt, and it will be cheaper to put panels up than it will be to burn coal.

      Yeah, but that's $1/watt year round and including downtime for clouds.

      Besides, you still need some other form of power for when the wind ain't blowin' and sun ain't shinin'. So you either need to add the cost of moving power around or you need some hydro/nuke/tidal/fossil plants.

    • Don't get me wrong, I'm all for increasing solar, wind, ocean-based, and other 'passive' power systems. But, all the people talking about wind and solar seem to always leave off some important problems - That solar panel which is producing 1kw (or whatever) at noon on a clear sunny day might only be producing 150W on a cloudy day, and nothing at night. That wind turbine which is producing 1kw on a nice windy day might be producing nothing on a stagnant day.

      Now, I believe the counterargument to that is the i

  • by Khaloroma ( 1381853 ) on Friday January 30, 2009 @11:46AM (#26666841)
    For those of you who probably are not familiar with the nuclear industry, let me make a very simple description of how "Nuclear Waste" is classified.<BR><BR>

    Waste falls into three categories:<BR>
    Low Level Waste (LLW)<BR>
    High Level Waste (HLW)<BR>
    Transuranic Waste (TRU)<BR><BR>

    LLW is anything that has been exposed to a reasonably low level of radiation. This is typically things like gloves, towels, suits, etc. and their activity level is usually low enough to store in a temporary facility until the activity level in them dies off enough to be disposed of safely.<BR><BR>

    HLW is primarily spent nuclear fuel that, in places like France, is usually reprocessed, but here it is typically either sent to be disposed of or onto research facilities, disposal, or weapons.<BR><BR>

    TRU waste is what the article has been discussing, which is a big problem. TRU waste comes about as nuclear fuel is fissioned out into various fission products. Obviously these fission products are radioactive and all depend on the type of fuel, but for old LWR/BWRs, there is a significant amount of TRU waste coming out. If what they claim is actually true, then it will be a very big step in the right direction.
    • by osschar ( 442236 ) on Friday January 30, 2009 @12:00PM (#26667053)

      Man, you must be cold.

  • Life Cycle Analysis (Score:5, Interesting)

    by mbone ( 558574 ) on Friday January 30, 2009 @11:47AM (#26666865)

    This idea was (in some sense) around in the 1960's, believe it or not.

    The high neutron flux produced means that the CFNS would itself become radioactive, and the steel of its construction weakened by neutron irradiation. I would like to see a life-cycle analysis to make sure that the total waste consumed was more than that produced by the CFNS itself.

    This general issue is why I would like to see a lot more emphasis places on He3 fusion, and also on linear fusion devices. (He3 fusion, either He3 - Dt or He3-He3, produces much less neutron flux. To me, the end goal would be to have nuclear fusion power that did not produce radioactive waste, which ITER definitely will do. Linear fusion is for spacecraft propulsion, of course - it is thought to be much easier technically than making a tokomak work.)

    • Linear fusion device? As in a z-pinch device? Such things have been tried before. How are you going to deal with the end losses? You still to need to confine a plasma in a magnetic field. If it is linear, it needs magnetic mirrors at the end. The charged particles need to stop there and return back to the center. How are you going to deal with these energy losses? Why not combine solar cells with a hall thruster for you spacecraft propulsion?
    • Re: (Score:3, Insightful)

      by jonored ( 862908 )
      On the other hand, this machine would then be converting what they are asserting is hard to deal with transuranic waste to mere irradiated metals - this might be a situation where it really would be better to need to dispose of irradiated reactor parts rather than a smaller mass of worse waste. They are wanting to use this to take just the hard to burn fraction of the waste, and burn that to get rid of it - most of the waste is burning in normal breeder reactors like the ones other countries use and the US
      • by mbone ( 558574 )

        Plausible, but, as I said, I would like to see a life-cycle analysis to see if the numbers really work out.

  • I remember when the post-Starbuck crew of BattleStar Galactica made it to Earth and solved this problem, too bad the computer went on the fritz

  • Breeder reactors? (Score:4, Insightful)

    by LSD-OBS ( 183415 ) on Friday January 30, 2009 @12:07PM (#26667133)

    Forgive my vast amounts of ignorance on the matter, but I thought breeder reactors [] were a viable way of burning nuclear waste down to nothing. Or is this the same thing? I'm

    Either way, it's good to know there are options to hush up them "ZOMGZ NEWKEELER HOLLERCAUST!" crowd that's so vehemently opposed to the cheapest and quickest to implement short- to mid-term solution we have to burning fossil fuels.

    • Re: (Score:3, Informative)

      by jonored ( 862908 )

      From what I can tell, this is asserting that breeder reactors can't effectively burn some of the elements that get produced, and this can. If you read carefully, they do mention that they want to do most of the reprocessing in less exotic reactors, and then just take the stuff that those can't effectively burn and "hit them with a sledgehammer", i.e. expose them to a much stronger neutron source, to burn /those/.

  • I see a couple of problems to start. First, it sounds like they want to reprocess spent fuel first. This does not fly in the US.

    Second they want to have one of these for every dozen or so conventional reactors. This means transporting waste and an inevitable accident. They might be able to build one of these transmuters and take it around to each decommissioned power plant site to help with clean up, but what of the transmuter itself? How soon does it become radioactive waste?

    I think I'd like to
  • by greg_barton ( 5551 ) <> on Friday January 30, 2009 @12:20PM (#26667327) Homepage Journal

    The liquid fluoride thorium reactor [] can burn existing nuclear waste just fine, and it's been available since the 50's.

  • by Anonymous Coward

    We've had it for decades. It has such a high burnup that spent fuel can be returned directly to the ground, because it is less radioactive than natural uranium ore. The submitter is uninformed, or a luddite moron shilling for the enviro-freaks.

  • While this invention may mitigate some of the nuclear waster there is still the issue of contaminating the environment while extracting fuel. I don't think this fact should stop anyone from building this reactor or any nuclear reactor. After all, global warming is, uh, global and any incidental contamination due to mining is merely local. It's just another problem that needs to be solved.

Things equal to nothing else are equal to each other.