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Compost heap spontaneous combustion.
bédé
Posts: 3,095
I read at the peak of the drought and wild fires, that compost heaps had been blamed for staring the fire. Is that likely? Does anyone have any first-hand experience?
location: Surrey Hills, England, ex-woodland acidic sand.
"Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
"Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
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I think @Dovefromabove knows about such things
From working in a petrochemicals plant, I know that carelessly discarded oily handwipes have been blamed for starting fires. But that is not a good reason to extrapolate to vegetable matter.
(I tried to add this latest comment to my original question. But the system said "no".)
"Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
I've never known a compost heap to overheat although I have seen them, and large farm muckheaps, steaming on a cold day. I suppose it might happen ... 🤷♂️
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
I steam on a cold day, but I try to keep at 37ºC.
As you know from lighting fires, heat begets heat, it's a chain reaction. At about 60ºC protein structure is destroyed which would kill all organic organisms. To my thinking, that would stop the production of further heat. Even if it rose to boiling point, the temperature would still be below ignition temperature.
There must be an answer, but I don't know it. Do you have any suggestions of a reliable scientific study of silage/haystack fires? I'll wait for more comments, and then give google a good roasting.
"Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
When hay is being made, special attention should be paid to the 'leaf joints' of the grass which take longer to dry out than the rest of the grass ... sometimes the farmer is in a hurry (rain is forecast etc) and the hay is baled and stacked too soon. If the weather is kind hay bales can be left out for a few days which helps reduce the risk of overheating, but sometimes the farmer feels forced to bring them in ... then the best he and his workers can do is to try to identfy the bales which seem risky and build the stack with them on the outside ... but it's a risk ... one bale overheating and a whole barn can go up in flames ...
https://www.ag.ndsu.edu/news/newsreleases/2011/july-25-2011/don2019t-risk-hay-fires/view
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
Any pile of organic matter will heat - our horse poo piles were always steaming in winter, and they were just in a corner of the field in the open.
"Compost needs to reach significantly high internal temperatures before the compost begins to burn or for the compost to ignite other material.
The internal temperature of the compost would need to reach temperatures of between 300°F to 400°F (150°C to 200°C) to be hot enough to result in combustion.
The temperature in a hot compost pile typically reaches between 115°F and 160°F or 46°C and 71°C. Under normal conditions, this temperature range is insufficient to result in a fire in the compost pile."
I haven't attributed this.
I have also read that resinous materials are more of a risk. I have a fair amount of cedar needles and conifer trimmings in my compost heap. Although my heap is far from being a problem.
I have also found that the correct word is: auto-ignition. Self-combustion is a different thing.
"Have nothing in your garden that you don't know to be useful, or believe to be beautiful."
It interests me as I can't see how the damp and sludgy mess of a compost heap can possibly catch fire and agree with the explanation you've found, my own heaps get up to the high 60s and no book or article i've read has seen anywhere near 90 or 100c in a compost pile, even one which has been purposely built for heat.