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Author Topic: Does Spontaneous Combustion Exist ?  (Read 14489 times)

Offline neilep

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Does Spontaneous Combustion Exist ?
« on: 27/03/2008 21:06:56 »
Dear Chilli Eaters and Pyro Experts,

see Ronald here ?



...hmmmm...well ewe can't really can ewe ?....Ronalds gorn and spontaneously combusted !!...serves him right for eating too many Maccydees !!


Nice shoes though !!


Is Spontaneous Combustion a real thing or is it just a lorey fable  ?

if it does exist ....how does it do what it does ?

Can I cook marshmallows around a spontaneously combusting person ?



Hugs et les shmisheys


neil
xxxxxx

mwah mwah !





 

lyner

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Does Spontaneous Combustion Exist ?
« Reply #1 on: 27/03/2008 21:27:24 »
Pork flavour?
 

Offline DoctorBeaver

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Does Spontaneous Combustion Exist ?
« Reply #2 on: 27/03/2008 21:29:46 »
It's a controversial subject akin to UFOs. If you believe it, you believe it. If you don't, you don't. There is no hard and fast evidence either way, although some cases that were thought to be spontaneous combustion turned out not to be.

I remember seeing a program on TV a few years back about a girl who apparently spontaneously combusted on the school stairs. Although no-one actually saw it start, many eye witnesses who were in front of her on the stairs said she was fine 1 minute, then they heard her scream, looked back at her, and she was on fire. Others were behind her and the fire started on her front so they didn't see it start either. Although several theories were put forward, there was no conclusive evidence.

I keep an open mind on the subject, although I do tend toward the sceptical.
 

Offline DoctorBeaver

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Does Spontaneous Combustion Exist ?
« Reply #3 on: 27/03/2008 21:32:03 »
Here's an interesting article about it http://science.howstuffworks.com/shc.htm
 

Offline Karen W.

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Does Spontaneous Combustion Exist ?
« Reply #4 on: 27/03/2008 21:40:37 »
Hee hee... I have felt that way lately a lot!! When they give you iodine cat scanned and inject the iodine it fills your blood with this very quickly rising heat wave that spreads all the way through your body!... the first one I had was not hot but very warm.. the second one I had was very hot the last one I had was so hot i had to holler cause I literally felt like I was on fire!!!

Now that has been a couple months ago over the period of 2 months..Then the last few weeks I have been having that happen during my weird episodes..... then I feel so hot... it hurts... after the breathing problems settle the heat goes away.. Doctor said it is not hot flashes but  I do not know..

I have read things about this... but have not learned much! I have often wondered if a human can build up so much Gas that theu can actually be sparked by an electrical trigger light turning on a lamp switch, after releasing large amounts of methane through flatulence!??? Do you think that is possible...

The stories I have heard was that the reported cases they felt the fire started within the body... I wonder though!

Did those shoes too! LOL.. I just Love clowns!
« Last Edit: 27/03/2008 21:42:15 by Karen W. »
 

Offline Bass

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Does Spontaneous Combustion Exist ?
« Reply #5 on: 27/03/2008 21:46:32 »
McDonalds recently started serving Rocky Mountain Oysters here in Montana---



They call them (GROAN) McNuts.   :o
 

Offline DoctorBeaver

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Does Spontaneous Combustion Exist ?
« Reply #6 on: 27/03/2008 22:21:59 »
McDonalds recently started serving Rocky Mountain Oysters here in Montana---



They call them (GROAN) McNuts.   :o

 

Offline JnA

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Does Spontaneous Combustion Exist ?
« Reply #7 on: 28/03/2008 06:23:16 »
I'm sceptical   
 

Offline JimBob

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Does Spontaneous Combustion Exist ?
« Reply #8 on: 30/04/2008 09:51:59 »
I think it's a load of bull nuts
 

lyner

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Does Spontaneous Combustion Exist ?
« Reply #9 on: 30/04/2008 11:44:42 »
Aside from the problem of actually getting the fire started, which must involve some outside stimulus - match, spark etc., you need to look at the energy needed.
There is a lot of water in the body (~70%) and that would have to be 'boiled off' before the fire would be self-sustainable (just like a bonfire with green wood. There needs to be enough fuel on board to do this. Ignore the fact that there is a mixture of tissues and structures, each kg of body will contain 0.7kg of water. The energy needed to evaporate this would be about 1.6MJ. If you used fat as a fuel for this, with an energy content of about 4MJ per kg, you would need about 0.25kg and there's 0.3kg available.
This is 'marginal' but worth following up. It implies that there is the right sort of amount of fuel available if everything is arranged right. You will have other heat losses and not all the non-water in the body is fat. You could rely on some of the water content just draining away and not needing to be evaporated - god this is getting more and more gruesome.
To get the fat to burn, you would need some sort of 'wick' - like a candle. Thick clothing could achieve this and also avoid too much heat loss. The pictures of 'spontaneously' combusted bodies always show the legs unburned - this could be because the heat loss is too great to keep the fire going (it supposes that the arms were alongside the body).
I seem to remember an experiment / demo on TV in which they tried to get a pig's carcass to burn. I can't remember how well it worked.
Crematoria don't do it the best way, clearly; they have very high gas bills and they could cut down if only they used effective wicks.

But, the 'spontaneity' issue - that is very unlikely - very few things burst into flames just like that.
 :)
 

Offline GBSB

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Does Spontaneous Combustion Exist ?
« Reply #10 on: 30/04/2008 16:34:17 »
I can’t believe it that still no one came with explanation that spontaneous combustion is happening because of vitamin deficiency …

….or because some people have genetic predisposition to end up suddenly burn to ashes…..

…. or that because of vitamin deficiency/because of some gene the stem cells turn in to the flame cells ….. 
:o.. ;D
 

Offline Bored chemist

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« Reply #11 on: 30/04/2008 18:35:23 »
spontaneous combustion is well documented. Spontaneous human combustion is another matter.
 

another_someone

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Does Spontaneous Combustion Exist ?
« Reply #12 on: 30/04/2008 19:36:25 »
There is a lot of water in the body (~70%) and that would have to be 'boiled off' before the fire would be self-sustainable (just like a bonfire with green wood. There needs to be enough fuel on board to do this. Ignore the fact that there is a mixture of tissues and structures, each kg of body will contain 0.7kg of water. The energy needed to evaporate this would be about 1.6MJ. If you used fat as a fuel for this, with an energy content of about 4MJ per kg, you would need about 0.25kg and there's 0.3kg available.
This is 'marginal' but worth following up. It implies that there is the right sort of amount of fuel available if everything is arranged right. You will have other heat losses and not all the non-water in the body is fat.

But I'd have thought that much of the non-mineral, non-water component of the body is combustible (proteins and sugars should be able to burn just as well as fat).

The problem as I see it is not the lack of fuel, but the lack of oxygen (a rapid burn of the body would not allow oxygen from the air to reach the deeper levels of tissue fast enough to oxidise them before the layers above exhause themselves and quench the flame).

But, the 'spontaneity' issue - that is very unlikely - very few things burst into flames just like that.

A number of scenarios could come to mind.

Maybe the simplest would be a buildup of heat in the guts due to anaerobic bacterial activity, this possibly also generating a fair degree of methane that might have a lower flashpoint temperature (although this only works if you then later somehow introduce oxygen into the previously anaerobic mix).

The other alternative would a a buildup of heat by some sort of runaway metabolic process (e.g. rapid acceleration of the ATP cycle due to some biological anomaly).  But still the problem of how is rapid burning created from that heat.  Slow burning would mean a limit to the amount of heat that can be built up as the non-biological oxidation would undermine the biological heat producing process; but rapid burning would mean some sort of cross-over has to be reached that delays non-biological oxidation until sufficient heat has built up from the biological process.

Could it be that some biological process (possibly due to a bacterial infection) creates the buildup of some highly flammable substance in the tissue (possibly gaseous, but more likely simply volatile), and once some saturation level is reached, something triggers the initial flash causes the tissue to start to exude the flammable volatile throughout the body, causing rapid combustion as the volatile reaches the surface of the tissue?

The other possibility is that the bacteria, rather than generating a volatile combustible, actually generates an oxidiser that saturates the body (rather like soaking paper in saltpetre - possibly something like hydrogen peroxide), and a flash at some point then causes triggers the oxidiser mixed tissue to combust.

The problem is, how many easily combustible volatiles, or oxidisers, exist that could build up in the body to a level that it could cause rapid combustion without first causing serious illness, and probably death, simply by interfering with the natural biological processes?
 

lyner

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Does Spontaneous Combustion Exist ?
« Reply #13 on: 30/04/2008 23:46:47 »
Quote
But I'd have thought that much of the non-mineral, non-water component of the body is combustible (proteins and sugars should be able to burn just as well as fat).
True, but fat has more energy content. In any case, it was just a ball park calculation to show that it is not impossible - once you get the bonfire going. It would be much easier to get a tree to burn but it wouldn't be very newsworthy.
 

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Does Spontaneous Combustion Exist ?
« Reply #13 on: 30/04/2008 23:46:47 »

 

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