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No thorium power?

  1. Mar 22, 2015 #1

    I am curious, what is keeping us from having thorium fission reactors? What are the hurdles that we need to overcome?
  2. jcsd
  3. Mar 22, 2015 #2

    Doug Huffman

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    Economic. Uranium infrastructure is extant. Technological, molten solid coolant is problematic.
  4. Mar 22, 2015 #3
    What else are we going to do with uranium anyways.
  5. Mar 22, 2015 #4


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    There's also the political angle. Just as nuclear power was starting to get popular again, Fukushima Daiichi happened, which is a real shame. If I recall, the thorium cycle produces less waste, is more abundant on the planet, and cannot be weaponized (or not very easily), so it has little to no proliferation concerns.
  6. Mar 22, 2015 #5


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    One big obstacle is that thorium itself doesn't fission. Thorium-232 captures a neutron and then decays into U-233, which is capable of fission. However, this decay process involves the emission of gamma radiation, which makes handling irradiated Th-232 material very dangerous.


    The irradiation of thorium also produces U-232, which is not fissile, but which also produces gamma rays as it decays.

    All in all, thorium is not the cheap nuclear fuel which has been portrayed by some.
  7. Mar 22, 2015 #6
    Alright then, 2 more follow up questions:

    1) Does it really have to be molten solid coolant? Whats wrong with using thorium with water coolant? And why is liquefied solid coolant such a big problem, I know of at least 1 place where it is in use, the solar tower in spain...

    2) How long is the decay of the thorium waste compared to uranium?
  8. Mar 22, 2015 #7

    Doug Huffman

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    Fission byproducts, waste, are a spectrum. A long lived thorium waste product is 232 Pa with a half-life of 32,760 years. But a long half-life makes for a lower specific activity.

    Molten coolant is often the solvent for the dissolved fuel.

    Coolant other than water will become activated, radioactive, a leak then is a leak of solidifying radioactive material. See the Monju disaster.
    Last edited: Mar 22, 2015
  9. Mar 23, 2015 #8
    Ahh, yes, makes sense, to stiffen up is a lot better than to spill around. But what are the problems with implementation? I know that there's a solar tower in spain that uses molten salt to generate power when there is no sunlight, like at night.
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