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Sponaneous Combustion

  1. May 13, 2005 #1

    JamesU

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    What is spontaneous combudtion? does it kill? And, what does it look like?
     
  2. jcsd
  3. May 14, 2005 #2

    Chronos

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    My grandfather was an avid gardner. I remember him making a huge pile of compost from sheep manure, straw and lawn clippings. I was conscripted into gardening duty one summer day, assigned to spread compost around the melon mounds. After removing a few pitch forks from the mound, smoke emanated from the cavity. I then observed a dry leaf burst into flames when it fell into the smoking cavity. In the farm belt, barn fires have been blamed on spontaneous combustion of green hay bales. In theory, fermentation is the cause of the heat build up. It is a controversial theory because the same heat would kill the responsible microbes. But I have seen it, hence believe it possible.
     
  4. May 14, 2005 #3
    Linseed oil, alkyd enamel resins, and some drying oils can ignite spontaneously due to auto-oxidation {just being exposed to air}.
    When I was in highschool art class a linseed oil soaked rag was tossed in the waste basket, a few hours later it went up in flames.
     
  5. May 14, 2005 #4
    when i saw the original post, i thought of spontaneous human combustion..

    keep in mind that a human being (and most animals for that matter), being composed of sugars and fatty acids, are combustable. Ever observed a grease fire while grilling? The net oxidation of glucose down to CO2 is a highly exothermic process, releasing a great deal of energy in the form of heat. It is only because we have very specialized enzymatic pathways in our cells that this reaction proceeds in little steps at a time, so that the energy can be harvested and the process regulated. Likewise for the beta-oxidation of fatty acids.

    It has since been noticed that cases of human combustion all had several variables in common: people who were non-mobile (usually older or disabled individuals) and a source of fire.
     
  6. May 14, 2005 #5
    quetzalcoatl9, shhhh...
     
  7. May 14, 2005 #6
    Very cool story.

    Fermentation would mean that alcohol would have been produced wouldn't it? I wouldn't think this would take place in the whole mass of hay at once. While some microbes die soon, others would still be generating heat at the periphery.
     
  8. May 14, 2005 #7

    matthyaouw

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  9. May 16, 2005 #8
    I have experienced the compost mound phenomena too when I was a kid! My dad actually cooked an egg in there, but there were no sheep droppings, so don't give me that disgusted look! :P
     
  10. May 16, 2005 #9
    I hope this returns what I intended it to.

    The Bob (2004 ©)
     
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