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Capturing radioactive particles in air

  1. Jan 31, 2013 #1

    I know that there are several way to capture radioactive particles in water, but does anyone know how to capture the particles in air? I thought above using moisture to trap the particle, but what if temperature is very low hence hard to introduce moisture? Is there any other ways to trap the radioactive particles in air?
  2. jcsd
  3. Jan 31, 2013 #2
    HEPA filters.
    Bubble air through some water.
  4. Jan 31, 2013 #3
    I actually meant air as in the atmosphere, open air.
  5. Jan 31, 2013 #4
  6. Feb 1, 2013 #5


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    What about those two examples says that it isn't using open air?
  7. Feb 1, 2013 #6
  8. Feb 1, 2013 #7
    did you mean "HEPA filters and Bubble air through some water" ?

    I am trying to work out how to prevent the radioactive particle from traveling through the air so I'm really looking for some method that can attract the radioactive particles and capture them in air, like how Zeolite would capture the radioactive particles in water.
  9. Feb 1, 2013 #8


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    Ah I see. You want to disperse something over a wide area that will trap the radioactive particles.
  10. Feb 1, 2013 #9
    The progeny of alpha emitters are ionized. If you have a statically charged surface, they will stick to it.
  11. Feb 2, 2013 #10
    yes, exactly. it would normally be possible to capture it using moisture in the air? but I wonder what if the temperature is really low can moisture can't be form? there must be other way to capture the radioactive particles...

    so it would be exactly opposite for the beta emitters?
  12. Feb 2, 2013 #11


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    Winnie I have no doubt that moisture in the air will capture at least some radioactive particles. Rainfall and other precipitation does have the effect of clearing the air. HOWEVER, remember that some radioactive particles are actually gasses and will not be cleared out like others will be.
  13. Feb 2, 2013 #12
    Thanks Drakkith, thats a very good point. I don't think I have a clear picture of how radioactive gasses behave, do you have any suggestion where I can find out more?
  14. Feb 2, 2013 #13


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    I can't say I do. I am not an expert in nuclear engineering. However, I would recommend that you first find out what radioactive particles you are wanting to trap. Are you doing this as an amateur project, or do you have working knowledge of radioactivity?
  15. Feb 2, 2013 #14
    no, I'm actually an architecture student, I'm just researching for my building design, I'm trying to capture Caesium-137 and Strontium-90.
  16. Feb 2, 2013 #15


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    those isotopes would be deposited on dust particulates, to one simply needs filters in the air intake system.

    Sr and Cs isotopes are either direct fission products are come from decay of precursors, which are fission products.

    Se > Br > Kr > Rb > Sr, and Sr decays to > Y

    Te > I > Xe > Cs, and Cs decays to Ba > La

    One would probably want a coarse filter followed by a bank of HEPA filters, with minimal pressure drop to minimize energy required for airflow.

    Halides, Br and I are absorbed on activated charcoal filters, which is best done at the source.
  17. Feb 2, 2013 #16
    Thanks Astronuc.

    Sorry for my lack of knowledge here, so you mean to try to absorb Br and I before they decay into Sr and Cs? What if it is already at the stage of Cs and Sr? Would I be able to some how capture them as they release into the air? is there other option besides filtering the air?
  18. Feb 2, 2013 #17


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    I was providing the decay chains. The place to capture Br and I is at the nuclear plant, which is what plant systems are designed to do. Radionuclides of Br and I decay to corresponding Kr and Xe isotopes, and being noble gases, they cannot chemically react, so they are readily transported in the atmosphere. Radionuclides of Kr and Xe decay to Rb and Cs, and these will deposit on surfaces and on dust, where they decay to Sr and Ba respectively. Rb and Cs are like Na and K, so they are readily soluble in water, and will usually be found in the ground or water. For a building, air filtration through a coarse filter followed by a fine filter works best.
  19. Feb 3, 2013 #18
    If you want help, why don't you first describe what you are trying to do?

    Are you designing an office building on the premises of NPP?
    Or a nuclear shelter?
    Or an ordinary office skyscraper which for some reason needs to be made safer against fallout?
  20. Feb 3, 2013 #19
    it is going to sound strange what I am trying to do, but bear in mind its a imaginative student project.

    My site is in chernobyl and I am designing a lab surrounding the red forest, trying to capture the state of ruin of the forest. Hence I would aim to capture whatever radioactivity that is trying to escape out of the boundary of the lab and feed it back into the forest.

    That would achieve two things : 1. keep the state of ruin and strange plant growth in the red forest, 2. stop future radioactive pollution out of the boundary of the project.

    One key point is that the lab that surround the forest would not provide a cover so my key concern is how to stop the radioactivity escape / spread beyond the boundary of the lab.

    I might as well list all of my concerns here actually:
    1. how to stop the radioactivity escape / spread beyond the boundary of the lab
    2. how does radioactivity travel through soil, hence knowing how to design the foundation of the lab to stop the escape of radioactive particles
    3. I'm sure the radioactive level would vary at different height of the atmosphere but not yet know how... i.e. if there is any data of radioactive level of chernobyl in section rather than in plan
    4. is there a way to maintain the radioactivity in the site in a long term view (once the original sources had finished its decay)
  21. Feb 3, 2013 #20
    In order "to capture the state of ruin of the forest", you can simply walk into it, collect samples and do whatever tests you want on them.

    > stop future radioactive pollution out of the boundary of the project.

    There is no definite borders of contaminated areas in Chernobyl. Concentration of radionuclides in soil simply gradually decreases as you leave most contaminated areas.

    And anyway, it was found that soil contamination is not very mobile. It moves at best a few tens of meters per year.

    Perhaps the most efficient transfer of radionuclides happens with forest fires. They can be prevented by standard forestry techniques.
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