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Hitachi Developing Reactor That Burns Nuclear Waste 200

Posted by samzenpus
from the no-waste-zone dept.
Zothecula writes The problem with nuclear waste is that it needs to be stored for many thousands of years before it's safe, which is a tricky commitment for even the most stable civilization. To make this situation a bit more manageable, Hitachi, in partnership with MIT, the University of Michigan, and the University of California, Berkeley, is working on new reactor designs that use transuranic nuclear waste for fuel; leaving behind only short-lived radioactive elements.
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Hitachi Developing Reactor That Burns Nuclear Waste

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  • Good (Score:4, Insightful)

    by geekoid (135745) <dadinportland @ y a hoo.com> on Wednesday September 03, 2014 @06:44PM (#47821289) Homepage Journal

    Can we get more companies doing these please?

    • Re:Good (Score:4, Insightful)

      by perpenso (1613749) on Wednesday September 03, 2014 @07:27PM (#47821623)

      Can we get more companies doing these please?

      Lets not forget the gov't research labs -- it would be nice if the U.S. gov't didn't shut down such research to appease an ill-informed political interest group.

      • Re:Good (Score:5, Insightful)

        by newcastlejon (1483695) on Wednesday September 03, 2014 @10:11PM (#47822357)

        Lets not forget the gov't research labs -- it would be nice if the U.S. gov't didn't shut down such research to appease an ill-informed political interest group.

        Otherwise known as "the electorate".

        • by perpenso (1613749)

          Lets not forget the gov't research labs -- it would be nice if the U.S. gov't didn't shut down such research to appease an ill-informed political interest group.

          Otherwise known as "the electorate".

          No. Otherwise known as one particular political party's minority that has disproportionate power during primary season. Something very far from the electorate at large. Not to suggest the electorate is well informed on matters of science and engineering, but those few with deeply held political beliefs take scientific denial and misinformation to a new level.

          Both political parties have their respective science deniers who will "primary" candidates who don't tow their line. Deniers have their respective a

        • Electorate, schmectorate, decisions like this are based on who provides the most campaign donations.
      • The proposed reactor design sounds a bit like the EBR-II at INEL, formerly the National reactor test site, with the design also referred to as the Integral Fast Reactor. This program got shut down in the 1990's, though stories have been told about people who were sent out to Idaho to shut it down came back as converts to the cause.
      • by tomhath (637240)
        Jimmy Carter ordered a stop to all reprocessing. His decision was shortsighted and ill-informed, but at least what we call "waste" is still useful a fuel as soon as the ban is lifted.
    • by LWATCDR (28044)

      No Nuclear is bad and dangerous.
      Actually this is not new. Many reactor designs that do this have been tested over the last few decades. Also fuel reprocessing does much the same thing. You are left with a few highly radioactive elements with short half lives. Some of those elements could be used for research and some could even be used as power sources in RTGs.

  • by Anonymous Coward on Wednesday September 03, 2014 @06:45PM (#47821301)

    Hitachi!

  • This is just so they can build more powerful wands.

  • Don't LFTRs solve the same problem?
    • by brambus (3457531) on Wednesday September 03, 2014 @07:19PM (#47821545)
      I don't think they do so in the breeder cycle - their neutron loss margins are fairly thin, hence why most designs propose extracting at the Pu-238 step (unusable for weapons, but great for space batteries). The burner cycle might be better in this regard. Fast reactors are able to do it, they have plenty of neutrons to spare.
      • If the Actinides already exist in abundant quantities, then they don't need fast neutrons?
        • by brambus (3457531) on Wednesday September 03, 2014 @07:42PM (#47821725)
          They don't, but the ratio of absorption to fission in the thermal spectrum for them is pretty bad, so that can mess up your neutron budget. Depends on the exact composition, though - each reactor produces a slightly different mix and that makes the TRU content in spent fuel fairly heterogeneous, which complicates reactor design and makes fabrication of reliable fuel fairly expensive (hence why MOX fuel only contains the Pu content, not all the other TRUs and even so it's much more expensive than fresh Uranium fuel).
    • I was confused about the use of water and burning Actinides because I believe it requires fast neutrons to occur at a high rate and water is a moderator. Also, if water getting out of the way lets the reaction rate increase, the void coefficient would be positive? I'm not sure which mechanism they intend to operate to burn the Actinides, but it sounds like they're trying to push derivative technology as being a safer, more reliable road in terms of tooling and design. This explains nothing of how the rea
      • by MrKaos (858439)

        I was confused about the use of water and burning Actinides because I believe it requires fast neutrons to occur at a high rate and water is a moderator. Also, if water getting out of the way lets the reaction rate increase, the void coefficient would be positive?

        It's a good point. I thought using water for a fast neutron reactor was something we had already moved past and were now considering using liquid metal, like lead, as a coolant with the reactor moderated by the design characteristics. Especially

  • Duh (Score:4, Informative)

    by Cyberax (705495) on Wednesday September 03, 2014 @06:59PM (#47821411)
    If you have a strong enough neutron flux then you can burn the waste (i.e irradiate it until it transmutes to something with a short-enough half-life). Unfortunately, only fast neutron reactors have neutron balance good enough to allow a significant fraction to be diverted for uses other than supporting the chain reaction.
  • Broken link? (Score:4, Informative)

    by BringsApples (3418089) on Wednesday September 03, 2014 @07:11PM (#47821481)
    Try here: new reactor design [gizmag.com].
  • Rendered for me as with no href. Second one works.
  • by quax (19371) on Wednesday September 03, 2014 @07:17PM (#47821533)

    By I much prefer inherently safe reactor designs. [wavewatching.net]

    • by brambus (3457531) on Wednesday September 03, 2014 @07:55PM (#47821815)
      I never quite understood the allure of ADS. To my eyes it just looks like an exceedingly difficult way of achieving criticality. Given a good design, a reactor will self-regulate by its own negative temperature coefficient, so an external driver isn't strictly necessary and shutdown can be performed by passive systems that are equally dependable as cutting power to the accelerator, e.g. by suspended or spring-loaded SCRAM rods. There is the interesting proposition of not having to reprocess the fuel when running a thorium breeder cycle in order to extract the bred fissile and load it into the core, since one can boost the neutron budget externally, but that needs to be weighed against the pretty steep cost of a high-powered accelerator (in terms of current, not just particle energies) and accelerator reliability issues.
      • by quax (19371)

        Don't think accelerator reliability issues are much of a concern any more, the systems are pretty mature at this point. I see the many advantage in being able to produce tailored neutron energy spectrum to process as much waste as possible.

        The latter is the main focus in my mind. Excess energy is just an added bonus. We need a process like this as burying the nuclear crap has become a politically untenable.

        • by brambus (3457531)
          I agree that burning the crap off is a good thing, but why tack on an expensive piece of extra equipment when pretty much the same effect can be achieved by being smarter about core design? I'm just not seeing the big advantage here.
          • by quax (19371)

            One advantage that is purely political is that sub-critical reactors will be more political acceptable.

          • I agree that burning the crap off is a good thing, but why tack on an expensive piece of extra equipment when pretty much the same effect can be achieved by being smarter about core design? I'm just not seeing the big advantage here.

            By all means, let's move forward on the smarter core designs. However, we still have lots of waste from the older cores to deal with.

      • Another huge problem is that they have no idea what to actually use to contain the coolant loop.

        Lead and Lead/Bismuth coolants are VERY corrosive and require active purification in order to keep oxygen levels down to incredibly low levels. Otherwise it'll corrode steel in a matter of weeks.

        There are several proposed alloys or coatings but as far as I can tell none of them have made it past initial research phases and all have their own downsides. Like, one may have good thermal characteristics but h
    • by Cyberax (705495)
      Except that they aren't safe. Even though they are subcritical, they'll still contain plenty of fuel. So there'll be more than enough decay products remaining to cause a meltdown in case of the coolant loss accident.
  • by Gliscameria (2759171) on Wednesday September 03, 2014 @07:22PM (#47821571)
    Nuclear waste is only a problem if you have a massive misunderstand as to the scale of the waste. We're not talking about literal mountains of waste, we're talking about under 100,000 tons - for all of it from the USA since forever. You can do one big project and store all of it, nearly indefinitely. The story of Yucca Mountain is what happens when you have to involve people that want a project to fail instead of just getting the damn thing done.
    • by Anonymous Coward on Wednesday September 03, 2014 @08:22PM (#47821925)

      >Nuclear waste is only a problem if you have a massive misunderstand as to the scale of the waste.

      Incorrect, sir. Nuclear waste is only a problem if you have a massive misunderstanding as to the thing you apply the label of nuclear waste. For it is not nuclear waste, it's unspent nuclear fuel.

      It would be foolish to build a massive pointless structure for nothing. Nobody's moving their nuclear "waste." It's not even waste to begin with. It's fuel.

      Have you ever heard of a Molten Salt Reactor? The most famous one I know about is the LFTR proposed by Kirk Sorensen. These types of reactors also burn existing nuclear waste, but they do so at atmospheric pressure, and are inherently safe. See: http://www.investing.com/analysis/thorium:-an-alternative-source-of-energy-224358

      We could build MSRs on site, so the fuel never has to be transported anywhere. Then we decommission the old dangerous water-based plants and run the safe waste-consuming molten salt reactors.

      OCCUPY CARSON CITY presented this idea to the Nevada Committee on High-Level Radioactive Waste 7/2012. https://www.leg.state.nv.us/Interim/76th2011/Committee/StatCom/HLRW/Other/ResponsestotheSOR.pdf

      This article confuses me because the Hitachi design is terrible. It uses pressurized water, which introduces all sorts of problems. The Molten Salt design is obviously better. I guess we'll just have to wait until 2020 to see how China does it.

    • by PPH (736903) on Wednesday September 03, 2014 @08:51PM (#47822055)

      Nuclear waste is only a problem if you have an agenda to make it one. Scream about the evils of reprocessing and the long life stuff piles up, eventually making nuclear power uneconomical. Perhaps that's what some people had in mind from the beginning.

  • They'll just modify the nuclear waste so that it becomes perpendicular.

  • by macpacheco (1764378) on Wednesday September 03, 2014 @07:50PM (#47821781)

    Humm, let's see.
    U-238 absorbs a neutron becoming Np-239 then decays to Pu-239
    Pu-239 has only a 2/3 probability of fission upon neutron absorption
    Water also has the tendency to absorb neutrons
    It's no wonder that no TRU burning reactor has been proposed that uses water or helium for cooling, it's always sodium, lead or molten salt as coolant.

    Also weird, is Hitachi already has a TRU burning design, the S-PRISM (GE/Hitachi project). Fast sodium reactors are actually known to be workable for that job.

    • by brambus (3457531)
      It's possible they plan to only burn stuff beyond Pu in there, as that can already be consumed in MOX (which however produces more of the higher TRUs for the reasons you noted). It's really hard to tell what they're trying to do here without more detailed data on the actual fuel composition.

      Also weird, is Hitachi already has a TRU burning design, the S-PRISM

      It's possible they're having trouble getting a dedicated TRU burner design approved and built (there might be little economic incentive and much public opposition to new nuclear plants, no matter the safety of the techno

      • Any water cooled reactor is inherently less safe than a metal or salt cooled reactor.
        Water/Gas cooled reactor = high pressure
        Anything else = low pressure
        Fully passive safety has been demonstrated with sodium and molten salt reactors.
        While AP1000 can be shutdown and kept cool without active safety systems, it does require lots of complex active systems while in operation.
        Still, non sense.
        PS: Any design that claims to burn TRU must be able to fission at least all transuranics. Any really great design will pur

        • by brambus (3457531)
          I'm not a fan of light water reactors either, but you need to understand that the public isn't aware of the details and intricacies of reactor design. To them terms which make an engineer cry happy like a little girl, don't mean anything. I mean FFS most of them still think nuclear reactors can explode like atom bombs. They saw Chernobyl and Fukushima, they saw "boom", it's a nuclear reactor, therefore "nuclear boom".
          I also think and hope education can change that, but that's a long road ahead and TRU-burn
  • This is nice to see and it is far more practical, in today's technology, than fusion. It's a way to keep existing technology working and reduce dependence on fossil fuels. I'm all for it!
  • Seems like a stream of protons (which is really just hydrogen ions) could be fired at nuclear waste to get it to split without making the next thing down the chain so neutron heavy as to make it radioactive itself. I would like to know how boiling radioactive waste is supposed to drop the half life. If it does I have some physics to brush up on.

    • by russotto (537200) on Wednesday September 03, 2014 @09:41PM (#47822229) Journal

      I'm pretty sure the energy required to add a proton to the nucleus of a large atom is prohibitive.

      • by Albinoman (584294)

        I guess I should ask what you mean by "pretty sure". Adding to large atoms are a lot easier than small ones. It's been a long time since I've read about it, but it's called "proton induced fission". Admittedly, most of the reading when you Google it is a bit heavy. I do know that if you crack U238 with a proton that all 3 daughter isotopes have a half life of 35 days or less (one is like an hour and a half) and their daughter isotopes are all stable.

        Anyway, if you Google "proton induced fission" and "nuclea

  • by iamacat (583406) on Wednesday September 03, 2014 @08:55PM (#47822085)

    Clean power that can bridge capacity/fluctuation problems of solar and wind is just what we have been waiting for. I hope all the world governments tax rebate and finance the heck out of this to bring it to market in time to make an impact on worst effects of climate change.

  • by brambus (3457531) on Wednesday September 03, 2014 @09:12PM (#47822137)
    Had to google the abstracts of the report and its conclusions are highly interesting. They claim to be able to breed at a ratio slightly above 1.0 in a BWR and even slowly consume TRUs by 10% per reprocessing step with unlimited reprocessing capability. Results of the report [epri.com]:

    The analyses collectively indicate that the two reactors appear to be able to achieve their design objectives: The RBWR-AC provides an equilibrium-cycle breeding ratio of slightly above 1.0, thus providing for a self-sustaining fuel cycle in which depleted uranium is used for the makeup fuel. The RBWR-TB2 is capable of unlimited continuous recycling of TRU while consuming on the order of 10% of the loaded TRU per recycle (after accounting for the newly generated TRU). Most results confirmed the values estimated by Hitachi. Some differences among the predicted reactivity coefficients need to be evaluated further.

    This has the potential to be a game-changer if true, as we could simply use existing reactor designs such as the ABWR (of which there are several operating already) to both burn waste and breed fuel indefinitely from U238 feedstock.

  • by neonleonb (723406) on Wednesday September 03, 2014 @09:32PM (#47822207) Homepage

    It's Hitachi! Can't they just wave their Magic Wand and make the nuclear waste go away? Think of the buzz that would create!

  • how apropos (Score:4, Funny)

    by Tumbleweed (3706) on Wednesday September 03, 2014 @10:28PM (#47822447)

    Hitachi means 'sunrise'. :)

  • ... transuranic elements are the only long-term problem in nuclear waste should please stay the hell away from designing nuclear reactors.

    http://en.wikipedia.org/wiki/L... [wikipedia.org]

    And that doesn't include "medium-lived" fission products like Cs-137 and its buddy Sr-90, both of which have half-lives of about 30 years.

  • by Chas (5144) on Wednesday September 03, 2014 @11:08PM (#47822627) Homepage Journal

    Is that this is another solid fuel, boiling water reactor. Which means they have all this Rube-Goldberg-esque over-elaborate over-engineering to control the plant in a shutdown state. And if they miss even one little thing, boom. Steam explosion.

    While burning up existing reactor wastes is a Good Thing, there are better, simpler, safer reactor designs for things like that.

  • by kriston (7886) on Wednesday September 03, 2014 @11:28PM (#47822709) Homepage Journal

    It's mostly a United States problem that waste isn't reprocessed. This is now and has been done on an industrial scale in Europe and the U.K. for several decades. For some reason the United States, under the guise of non-proliferation, will not permit reprocessing of spent commercial nuclear reactor fuel.

    The story in this article isn't news. Everyone knows how to reprocess spent fuel since before the 1960s. What would be actual "news" is the time at which the United States allows the well-proven, industrial-scale reprocessing to be applied to its own reactors.

    Even Canada does it. The United States' nuclear energy policy is laughably stupid. It's a shame, really.

    • by careysub (976506)

      It's mostly a United States problem that waste isn't reprocessed. This is now and has been done on an industrial scale in Europe and the U.K. for several decades. For some reason the United States, under the guise of non-proliferation, will not permit reprocessing of spent commercial nuclear reactor fuel.

      Nonsense. Any company that wants to open a fuel reprocessing plant can do so, they just need to apply for a license and be willing to pay the bills.

      Perhaps you mean that the U.S. government has decided not to run a fuel reprocessing plant at tax payer expense that produces fuel that no one will take unless paid upfront, and few can use anyway? There are no commercial fuel reprocessing plants anywhere in the world because they cannot make money, only spend it.

      Having sufficient reactors under construction tha

      • by squizzar (1031726)

        Well seeing as the US government took a huge amount of money from the nuclear generators over the years to fund a waste storage repository (which they are being sued over because of their utter failure to hold up their end of the deal) perhaps they could use that to pay for reprocessing? The electricity producers (and in turn, therefore, consumers) have already paid for it, taxpayers don't need to be involved.

  • by mrbill1234 (715607) on Thursday September 04, 2014 @04:47AM (#47823519)
  • Maybe I'm really wrong but wasn't a similar idea around during the Carter administration and halted due to potential dangers?
  • Isn't burning waste what fast breeder reactors do ? They already did this but it didn't make it somehow. Superphénix for example had a few technical issues but still managed to be commercially exploited for a time. If was shut down for political reasons.
    The current stand is to use reprocessing and MOX fuel.

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