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Is this for real?

  1. Nov 11, 2008 #1
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  3. Nov 11, 2008 #2

    Andrew Mason

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    It is for real. Whether it will perform as hyped remains to be seen. It does not appear to be licensed yet. Toshiba has a similar nuclear "battery" the 4S reactor. Hyperion, apparently, likes to refer to it as a battery rather than a reactor and it suggests that it is a chemical device. It is, however, a nuclear reactor that produces heat from nuclear reactions. It does not produce heat by chemical reactions.

    I am unclear as to how it is cooled.

    Last edited: Nov 11, 2008
  4. Nov 15, 2008 #3
    On a vague drawing, I saw a couple of barracks at the surface, one of which could be a cooler. You can just blow fresh air to cool steam. The consequence is that you waste power in the blower and have a too warm cold source, that's why full-sized reactors either use a big river or evaporate water in a natural convection tower.

    There are a few more questions I don't see a satisfying answer for...

    How do you protect the produced plutonium against theft? A government is willing to pay 10,000 people for years to build bombs. Attacking a few plants like this one is far too easy. Their plutonium contents is similar to any other reactor size. Shall users pay for 100s permanent troops to guard them? And for 10,000 police when removing spent fuel?

    Don't tell me about military grade. North Korea didn't need military grade, and their 500t explosion is undesirable. Worse, nuclear engineers would know how to make efficient bombs with waste grade plutonium.

    And imagine converting this plant into a dirty bomb. Dig a tunnel, put a chemical explosive, ignite, done. Those seeking surgical precision may first transport the plant where they want.

    That is, security can't be downsized around a reactor. Downsizing its power doesn't make sense.

    Where do you find enough uranium for everybody? Uranium deposits (known and estimated) have far less total energy contents than coal, gas and even oil. Uranium reactors are not a global solution, they may be one for a handful countries.
    Last edited: Nov 15, 2008
  5. Nov 15, 2008 #4

    Andrew Mason

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    There is plenty of U for thousands of years if we had the technology to use 100% of it instead of the 1% that current reactors use. See the recent https://www.physicsforums.com/showthread.php?t=216571"

    Last edited by a moderator: Apr 23, 2017
  6. Nov 15, 2008 #5
    These are supposed to be big and underground. How do you steal something like that without the whole neighborhood noticing? Not to mention the second you try to take it out, the power goes out and it's easy to trace where it isn't being supplied.

    Yeah. It seems like fertilizer is good for bombs, too. I guess we should outlaw it? How much effort would it take to get this stuff and make a bomb out of it vs. just making a "conventional" bomb?

    Right, you're going to transport something that huge without anybody noticing. Even having it explode won't be easy. Reinforced concrete doesn't just crumble. If you can get into something like that you might as well just take your equipment and do something else.

    [/quote]That is, security can't be downsized around a reactor. Downsizing its power doesn't make sense.[/quote]

    We guard military bases but we don't guard local Wal-Marts, even though they carry guns. There's a reason for that. It's not worth the risk.

    If these last for 40 years or whatever they claim, then that's already huge. You can think of something else in the mean time and other people can use other sources of energy.
  7. Nov 16, 2008 #6


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    This specific reactor, I don't know, but the Toshiba 4S was a breeder reactor, or better, had a breeding ratio of about 1. It could work, according to specs, about 30 years on one fuel load (and then just had to be "thrown away".

    As Andrew Mason said, breeders use way more than the 1% of the energy content current thermal reactors use of the uranium (with the 99% still left in the "waste" and in the depleted uranium).
  8. Nov 16, 2008 #7
    Enough uranium: Breeders are abandoned now. Every single now, though there were several attempts worldwide. And there are excellent reasons!

    Yes, proliferation IS a huge risk with a breeder - or rather, is certain. Its plutonium load is directly usable for a bomb. And if you don't want to explode the full plutonium load of the bomb, then it's easy to build one.

    It definitely makes a proliferation difference whether a state must produce the nuclear fuel for a bomb or can pick it from a reactor. That's the whole point of non-proliferation treaty and fuel control. North Korea, India, Pakistan, Argentina, Brazil, Libya, Iraq got the fuel from power plants for their bomb attempts.

    The only breeder that wouldn't proliferate is Carlo Rubbia's thorium scheme, but it's an incomplete proof-of-concept up to now, as building the powerful accelerator needs unclear technology, so it's far even from a prototype.
  9. Nov 16, 2008 #8
    Plutonium theft: again, states are willing to pay 10,000 people for years to get nuclear bombs. Stealing a few tonnes is easy, underground as well - or when the used reactor is being removed - and doesn't even need to go unnoticed.

    You grossly underestimate the criminal energy of a state.

    Let me take an example: about 10 years ago, all statues at Notre-Dame in Paris were beheaded. About 100 pieces. As you may suppose, there are permanently dozens of police in uniform right around Notre-Dame, and certainly more without a uniform. But people who beheaded the statues could even go unnoticed.

    Other criminal methods would be possible to transform a power plant in a dirty bomb, as the stakes are high. The commando doesn't need to come back home, as we all know now. And they can perfectly take the whole surrounding population as hostages.
  10. Nov 16, 2008 #9


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    The Russian BN-600 fast breeder reactor is still operating and has support from US and EU nations.

    It is not easy to extract spent fuel from a reactor and just take off with it. And even so, the spent fuel must be taken to a reprocessing facility in order to extract the Pu.

    One does not need an accelerator for a thorium breeder.

    Last edited: Nov 16, 2008
  11. Nov 16, 2008 #10
    Extracting plutonium IS easy because plutonium has distinct chemical properties. This is true from spent uranium fuel, and even easier for plutonium fuel as in a breeder. It doesn't need isotopic separation but just chemical operations. This is exactly what North Korea did, because it is easier.

    This is exactly what non-proliferation practices try to avoid.

    We were talking about exporting reactors so for the land that buys it, extracting fuel from a reactor and transporting it isn't an issue. In other words: Pu-loaded breeders can't be exported, as I said.

    Thorium breeder: I wrote about Carlo Rubbia's scheme which does need an accelerator - this is what makes it distinct. If you pretend to know nuclear technology, you can't ignore this. Rather a matter of bad faith.

    There are breeders (in Russia, yes) that use thorium as a fertile element and highly enriched uranium, or preferably plutonium, as a fissile one. However, they don't produce significantly more new fissile material than they consume Pu or 235U, so they can't take advantage of the important thorium deposits. It's rather a clever way of destroying excessive 235U or 239Pu from recycled weapons. And as they need 239Pu or highly enriched 235U, which are both easily separated from Th, they pose a high proliferation risk again.

    This is why Rubbia's scheme is the only breeder that can be exported without helping build bombs.

    You will need better arguments than "nonsense". Recently enough, a complete cargo ship with dozens of battle tanks has been stolen near Somalia.
  12. Nov 16, 2008 #11


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    As USUAL - you are 100% WRONG!! A breeder is not necessarily a proliferation risk.

    One can design a breeder reactor such that the plutonium is IMPOSSIBLE to make into a
    nuclear weapon.

    Argonne National Laboratory has designed such a breeder - the Integral Fast Reactor or IFR.
    Here is an interview conducted by Pulitzer Prize winning historian Richard Rhodes for PBS's
    Frontline with nuclear physicist and former Associate Director of Argonne National Laboratory,
    Dr. Charles Till:


    Q: So it would be very difficult to handle for weapons, would it?

    A: It's impossible to handle for weapons, as it stands.

    It's highly radioactive. It's highly heat producing. It has all of the characteristics that make it
    extremely, well, make it impossible for someone to make a weapon.

    It was my laboratory; Lawrence Livermore National Laboratory that did the analysis that
    concluded that it was IMPOSSIBLE to use IFR-bred Plutonium to make a nuclear weapon.
    That study is cited by US Senators Simon and Kempthorne in their letter to the New York Times:

    http://query.nytimes.com/gst/fullpag...54C0A962958260 [Broken]

    You are mistaken in suggesting that the reactor produces bomb-grade plutonium: it never separates
    plutonium; the fuel goes into the reactor in a metal alloy form that contains highly radioactive actinides. A
    recent Lawrence Livermore National Laboratory study indicates that fuel from this reactor is more
    proliferation-resistant than spent commercial fuel, which also contains plutonium....

    Senator Paul Simon
    Senator Dirk Kempthorne

    You just flat out don't know what you are talking about when you state that the plutonium is
    "directly usuable" in a nuclear weapon. What do you know about nuclear weapons design anyway?

    Dr. Gregory Greenman
    Last edited by a moderator: May 3, 2017
  13. Nov 16, 2008 #12


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    Once again you show you don't know what you are talking about. The Russian are NOT using breeders
    to destroy excessive U-235. They downblend the U-235 and SELL it to the USA.

    The program is called "Megatons to Megawatts" and is is run under the auspices of USEC; the
    United States Enrichment Corporation:


    In fact, about 50% of the uranium used to fuel the fleet of US power reactors currently comes from
    dismantled Russian nuclear weapons. That's why the above contains the statement:

    On average, one in 10 American homes, businesses, schools and hospitals receive electricity
    generated by fuel fabricated using LEU from the Megatons to Megawatts program—and this ratio
    is much higher in certain areas of the country.

    About 20% of the electricity in the USA is produced by the USA's fleet of nuclear power plants. If
    half the uranium is from Russian warheads; that means about 10% of the electricity used in the USA
    is from Russian uranium. Hence the "one in 10 American homes..." statement above.

    Dr. Gregory Greenman
    Last edited by a moderator: Apr 23, 2017
  14. Nov 16, 2008 #13


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    You are jsut a fountain of MISINFORMATION. Although it is true that chemical separation is
    comparitively less difficult than isotopic separation - it is by no means "EASY". In fact, the
    chemical processes that are used to separate Plutonium will flip the valence state about 19 times.

    Only Plutonium can run that gamut of valence changes.

    It's not EASY - just easier than isotopic separation.

    Additionally, the North Koreans did those operations in a manner that didn't have adequate
    safeguards, and in a manner that was dismissive of the health and safety of their workers.

    Dr. Gregory Greenman
  15. Nov 16, 2008 #14


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    You seem to be pretending to know nuclear technology quite well.

    Dr. Gregory Greenman
  16. Nov 16, 2008 #15
    What does that mean? I don't know much about chemical seperation.
  17. Nov 16, 2008 #16


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    Just curious though... couldn't this thing be used to make a dirty bomb?
  18. Nov 17, 2008 #17


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    Plutonium is one of the actinides - it has both an incomplete "d" orbital and incomplete "f" orbital.

    Therefore, like any of the transition metals - those with incomplete "d" orbitals; the element can
    take on several different valence states. You know that metals in the first column of the periodic table,
    for example Sodium; have an electron valence of +1. Those elements in the second to the last
    column, like Fluorine and Chlorine have a valence of -1. However, these transition metals don't
    have just one valence state - they can have several different valence states.

    A chemical separation process is really discriminating on the basis of valence - it is selecting an atom
    to go one way or the other in the separation based on the valence.

    The first step in the reprocessing of Plutonium, selects based on one of the valences that Plutonium can
    have. However, there may be other components in the mix that also have that same valence - so they
    will "follow" the Plutonium. So the next step selects on the basis of a different valence that Plutonium
    has. This process is repeated for other valence states of Plutonium.

    It's a little like trying to separate you out of a crowd of people based on asking questions. We say that
    anyone that has your birthdate can stay; but all the rest have to go. That doesn't guarantee we've singled
    you out of the crowd. So we say anyone that lives in the town you live in can stay; the rest have to go.

    If we keep doing that - selecting on criteria that apply to you - and if we do it enough times - we will finally
    get down to where the only person left is you. You are the only one with the given birthday, the given
    hometown, the given pet, the ...... You are the only one that can run the gamut of all those questions
    and still not be "voted off the island".

    Likewise, the processes that separate out Plutonium essentially makes 19 sequential tests of the valence
    of the atoms it is selecting - and Plutonium is the only element that has precisely the right set of
    possible valences to survive the gamut.

    Dr. Gregory Greenman
  19. Nov 17, 2008 #18


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    Yes you could steal one and drive it into the middle of a city, wrap explosives around it and blow it up.
    Wether it would do any more damage than flying a 737 into a skyscraper or blowing up an LPG tanker ship is debatable.
  20. Nov 17, 2008 #19


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    The "dirty bomb" threat is over-hyped. From Technology Review published by the
    Massacusetts Institute of Technology:


    "The Dirty Bomb Distraction

    The biggest danger from radiological weapons is the misplaced panic that they would cause."

    Dr. Gregory Greenman
  21. Nov 17, 2008 #20


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    In fact, Rubbia's reactor was a solution in quest for a problem. Rubbia, brilliant as he is, was an elementary particle physicist (as I am btw, but we don't play in the same team :redface:) and brilliant at that (Nobel prize and everything). However, he "solved" a problem that didn't need a solution: he must have thought that the principal problem of a nuclear reactor was to shut it down when it failed. He must not have heard of passive safety I guess. So his proposal does solve that: when the accelerator is stopped, the chain reaction stops. True. But the problem was already solved: western reactors also stop passively if it goes wrong. What is the true problem is to keep removing heat from decay of fission products just after the nuclear chain reaction stops, and to confine all that mess inside a containment building. The main problem is not to stop the reaction, the main problem is to cool, and to contain.
    Well, those aspects are not influenced positively by the presence of an accelerator (and the hole that is needed in the reactor building to bring in the beam and everything).

    As to the thorium conversion, I would rather say that in as much as one considers the U-Pu a proliferation risk, then the Th-U is much more of a risk. After all, one produces U-233, which can be separated chemically, but contrary to the U-Pu conversion, this material is much less active. Ok, there is some production of U-234 which is a hard gamma emitter, but there's not the panoply of minor actinides.
    Moreover, U-233, like U-235, can be used in a primitive gun-type bomb. I think that is the biggest problem.

    I don't say it is easy, and I don't say there aren't problems. But if one considers the U-Pu as a proliferation risk, then for sure, the Th-U conversion is problematic.
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