Homepage Forums Dense Plasma Focus (DPF) Science and Applications Could pB11 focus fusion device be modified to use thorium?

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  • #536
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    Tasmodevil44
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    Here’s a crazy idea. Don’t know if it would work. instead of focus fusion, could it be modified to focus fission if boron was substituted for thorium? It would produce considerably more radioactive material, but still not as much as coventional reactors. In a dense, hot plasma is it possible for the hydrogen proton (or even alpha particles of helium) to be absorbed by a thorium nucleus? And would it cause it to undergo transmutation into something else like U-233 or U-235 and then fission?

    It may even be possible to hybridize the dense focus reactor in such a way that you have both boron fuel and thorium fuel used simmultaneously. But it’s probably just another one of those longshot ideas not very likely to work-out.

    But then again, the two reactions might even aid each other and enhance reactions. The heavy atom fission reactions might dump more energy into the plasma to aid the boron reactions. Conversely, the boron reactions might supply more energy to aid transmutation of thorium into something that’s more fissinable.

    If the energetic fission products of a heavy atom like U-233 also exit the reaction site as a unidirectional beam…… just like alpha particles…… then the conversion of thorium to electric power might also be far more efficient than a conventional fission reactor. The heavy fission products could also be tapped by direct induction the same way. This would equate into far less radioactive material produced for the same amount of electricity generated. But I admit this is just an idea that may not work.

    #3162
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    belbear42
    Participant

    Thorium fission is done with neutrons, not protons.
    All you need is exposing thorium to a thermal neutron source (by simply placing it into a fission reactor)

    No energetic device like a DPF is needed for that.

    And I don’t think it’s even possible to use a DPF to fuse protons with thorium, which has a whopping 90 positive charges to overcome, boron has only 5.
    One needs a full-blown particle accelerator for that, while using neutrons is so much easier.

    Thorium itself is not even fissionable, but it can be used to start a fuel cycle, leading to uranium 233 which is fissionable.
    The “breeding” of Thorium 232 into uranium 233 however is as dangerous as breeding uranium 238 into plutonium 239. (also for making nuclear weapons)
    And it’s a very expensive process to extract the uranium 233 because of the high radioactivity of some byproducts such as uranium 232

    Norway considered using Thorium in 2007, because they have abundant thorium ores and no uranium, but they backed out before large investments were done.

    But p-B11 focus fusion is of course a FAR better alternative to any fission scheme, so once we have focus fusion, nobody will ever want to mess with heavy nuclei for power production again. (although some evil-minded may still want to mess with them to make nuclear weapons)

    #3163
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    Tasmodevil44
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    has a whopping 90 positive charges to overcome, boron has only 5.

    And also:

    No energetic device like the DPF is needed for that.

    That’s all the more reason why I thought that an energetic device like the DPF might make thorium undergo transmutation into something else that would fission instead of having to use neutrons. I also mentioned that other things like deutrium or an alpha particle of helium absorbed might also work. I’m very open-minded about possibilities most people would not be open-minded enough to consider. However, you’re definitely correct about one thing for sure……and that is this:

    the high radioactivity of some byproducts such as U-232

    You’re most definitely correct on this one. U-232 is a particularly nasty isotope to deal with. So that while I’m still open-minded enough to think that it might work…… even if it did, you would still have to manage the nasty consequences.

    #3167
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    belbear42
    Participant

    Tasmodevil44 wrote:

    has a whopping 90 positive charges to overcome, boron has only 5.

    And also:

    No energetic device like the DPF is needed for that.

    That’s all the more reason why I thought that an energetic device like the DPF might make thorium undergo transmutation into something else that would fission instead of having to use neutrons. I also mentioned that other things like deutrium or an alpha particle of helium absorbed might also work. I’m very open-minded about possibilities most people would not be open-minded enough to consider.

    Well, I think it’s all about energy balance. In this case definitely a negative energy balance: Shooting a proton into a Thorium will cost a LOT more energy than fission of the resulting uranium will ever deliver, especially since you cannot turn neutrons directly into electricity. It needs a thermodynamic circle.

    Thorium transmutation using neutrons costs no energy at all, even better: you are using a reactor that already produces energy. A DPF powerful enough to transmute thorium would be an energy guzzling device. After all, any fission stuff is done in solid state, not in plasma state. Turning highly radioactive elements into plasma state is EXTREMELY hazardous, while keeping them in solid state is much more controllable.

    And last but not least you will make your entire DPF machine so radioactive that it can only be maintained using hot-cell robotics and any parts you take out will be high-level radioactive waste.

    Believe me: DPF’s and fission are compatible. It’s a fusion device and fusion is done with light elements. And DPF’s are all about an attempt to “make watts, not rads”

    #3172
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    Tasmodevil44
    Member

    ……all about energy balance

    especially since you cannot turn neutrons directly into electricity. It needs a thermodynamic circle

    I also mentioned in my post that the heavy fission products (which are positively charged nuclei) may come streaming out in a unidirectional beam just like the alpha particles……and undergo direct inductive conversion to electricity the same way……making it far more efficient than conventional fission reactors (and less waste for the same amount of energy). Most of the energy of heavy atom fission comes from the positively charged heavy fission byproducts……not from the neutrons. Upon fission, they repel away from each other with incredible force. And because they are massive, they equate into considerable energy if they too can be converted by direct induction. Did you read this part? You must not have completely read it all.

    By far the biggest problem (like you and I both already stated before) is not really so much whether it would work or not for transmuting and “burning” thorium…… or the resulting energy balance…… so much as the radioactive problem even if it could:

    any parts you take out will be high-level radioactive waste.

    all about an attempt to “make watts, not rads”

    You and I both are still in agreement on this one. Even if it could theoretically “burn” thorium, had an excellent energy balance, and helped to contribute more energy to facilitate a mixture of pB11 fusion as well (as I described), you would still have the really wicked rad waste problem to contend with.

    The energy of the fission would come primarily from the heavy fission byproducts, not the neutrons. Instead of generating watts of power, the neutrons would be absorbed into the surrounding reactor walls…… and transmute everything else into a radioactive mennace……including the reactor itself. While producing substantially less radioactivity than a conventional fission reactor, it would still produce it nonetheless.

    Not to mention the fact that the U-232 produced is a really wicked and nasty alpha emitter. If you were to accidentally inhale even the smallest microscopic particle of U-232 into your lungs……and it became permanently lodged there……you could develop lung cancer.

    While I still think that such a thing may at least be theoretically possible…… (plasma may be energetic enough to overcome 90 protons. Especially if an energetic alpha occasionally collided with it.) ……is it very desirable or even something that you would really want to do?

    Well, so much for a dense plasma focus that can be modified to safely transmute and “burn” hazardous thorium. Guess we’ll stick with trying to obtain a safer fusion ignition with p + B11 for now, folks.

    #3173
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    Tasmodevil44
    Member

    In addition to the radioactive problem, you are correct about the energy balance, too. As energetic as the DPF is, you would still be fighting an uphill battle against the binding energy curve. And thorium is way beyond iron on the curve, where fusion starts to absorb energy rather than release it. You would need even more energy than the DPF can provide.

    Violent supernovae, anyone? We could cook-up some gold and silver while we’re at it.

    About the only other way a DPF might “burn” thorium (a very unlikely longshot) is if some of the energetic protons caused a secondary release of neutrons by way of the spallation effect or something similar to it. In fact, shooting a beam of energetic protons at a lead target to generate a secondary shower of neutrons is one of the ways physicists have proposed for a thorium reactor. But such an effect or something similar might not even work in a plasma.

    #3174
    Breakable
    Breakable
    Keymaster

    Basically there are 2 types of known atomic energy sources:
    Fission of heavy elements
    and fusion of light elements.

    Thorium energy could be harversted in fission, because its a heavy element.

    #3182
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    Transmute
    Member

    D+D or D+T fusion could be used to “burn” nuclear waste, but in general cheap fusion would end the nuclear industry, including theoretical thorium nuclear industry, the only nuclear industry that could be left would be fusion power nuclear waste destroyers.

    #3185
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    Tasmodevil44
    Member

    Spallation of proton beams into neutrons isn’t the only way to convert protons into neutrons. In some rare cases, positively charged protons will covert into neutrons by absorbing a negatively charged electron. In fact, that’s basically what a neutron is: an electron and a proton combined together into one particle. But this method is also very unlikely to occur.

    I had hoped that fission of a few heavy atoms might dump a little extra energy into the plasma to help things along a little better.

    Well, so much for the failed idea of trying to dump more energy into the DPF to try and get it over the fusion “hump” more easily. It would be too hard to get the thorium to transmute into uranium and fission. And it would ruin the whole elegant idea of clean “non-rad” power even if you could. But I’m still curious about the basic concept, though. Is there anything else you might be able to add to the plasma mixture that might add a little more energetic “uummph ! ! ! ” to it?

    If there is, I don’t know what such an additional “kick” or fusion stimmulus would be. Any suggestions?

    #3186
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    Tasmodevil44
    Member

    Or could something like what is used in an H-Bomb be added to the plasma mix? Such as lithium or beryllium? More than likely, it would not add any additional “kick” to the process, either.

    #3187
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    Transmute
    Member

    If the fusion “hump” is the problem just use deuterium or deuterium and tritium as the fuels, these require nearly 1/10 as much heat as p+B11 fusion, the only problem (which can be their advantage for nuclear waste destroying) is that d+d and d+t fusion produces high energy neutrons.

    #3189
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    belbear
    Member

    Tasmodevil44 wrote:
    I also mentioned in my post that the heavy fission products (which are positively charged nuclei) may come streaming out in a unidirectional beam just like the alpha particles……and undergo direct inductive conversion to electricity the same way……making it far more efficient than conventional fission reactors (and less waste for the same amount of energy). Most of the energy of heavy atom fission comes from the positively charged heavy fission byproducts……not from the neutrons. Upon fission, they repel away from each other with incredible force. And because they are massive, they equate into considerable energy if they too can be converted by direct induction. Did you read this part? You must not have completely read it all.

    I may have missed something but I am sure about one thing: If you shoot protons into Thorium, no fission at all occurs. Even if you do it the conventional way by shooting neutrons into Thorium, no fission occurs because thorium is not a fissionable nucleus. It will become an instable nucleus which eventually transmutes itself into fissionable uranium but this decay takes time, hours at least, far beyond the picoseconds you have inside a DPF plasmoid.

    What shoots out of the beam of your hypothetical thorium-burning DPF will be protactinium nuclei (element 91), and the fusion reaction does not yield energy, it costs energy and will cool your plasma instead of heating it.

    And after all, there is no need to “burn” thorium. Unlike plutonium, it is not a dangerous product we need to get rid of and the best thing you can do is to leave it where it belongs: In the earth as a natural ore.

    As been said before: A neutronic DPF can be used as a source of energetic neutrons to transmute the huge piles of nuclear waste we are sitting on into much shorter living elements, and that without generating new nuclear waste, as conventional high-flux reactors do.

    So focus fusion cannot only generate clean and cheap energy, it can also help us to get rid of the heritage from the “age of nuclear madness”

    #3192
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    Brian H
    Member

    Believe me: DPF’s and fission are compatible. It’s a fusion device and fusion is done with light elements. And DPF’s are all about an attempt to “make watts, not rads”

    I think you meant “incompatible”. DPFs are vastly more efficient than any possible fission rig.

    #3194
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    Tasmodevil44
    Member

    Transmute, you brought up a good point:

    If the fusion “hump” is the problem, just use d+d or d+t …… require 1/10 as much heat ……

    You are absolutely correct. Heavy hydrogen should “ignite” at lower temperature than the the p+B11 reaction. If hybridized fission/fusion is not workable, then why not this?

    #3195
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    Tasmodevil44
    Member

    Here’s still one more possibility. Don’t know if it would work, either (a chemical analogy of what I’m trying to do is somewhat like pour gasoline onto rain-soaked wood that’s all wet. Or put lighter fluid on stubborn charcoal briquettes). How about adding some He3 to the plasma mix?

    But I can already see one problem arising from He3 already. It is very scarce here on planet Earth. That’s why some scientists have proposed the idea of mining the Moon’s lunar soil for it. Over countless millenia, the solar wind from the Sun has deposited quite a lot of it there.

    However, He3 may be more probable at getting p+B11 fusion over the “hump” than trying to add any fissionable stuff to it……whether it be thorium, uranium, or anything else that’s fissionable. I even entertained the wacky notion of adding some Americium (like in smoke detectors) to the mix. But Americium is also scarce and may not so-called “burn” to add any more energy either.

    When thinking “outside-the- box” with an open mind, I try not to leave a single stone unturned ……no matter how crazy others may think it to be. While most ideas don’t work, you just never know when you might hit upon something that does. Even if 99 out of a hundred don’t work, then the one out of a hundred that does is still well worth it.

    I still think the suggestion by transmute to add some heavy hydrogen may be the best bet for adding a little extra “kick” to get p+B11 fusion going. But you would definitely produce some radioactivity when the high energy neutrons slam into the walls and are absorbed. Preferrably, the d+d that uses strictly deutrium might produce less high energy neutrons than the d+t reaction that uses tritium. The tritium has got to sling it’s extra neutron somewhere……like the reactor’s walls.

    But then again, like transmute said, these neutrons could also be harnessed to remediate existing stockpiles of the most wicked and nasty legacy of the Cold War and Arms Race.

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