Farmers/chemists-is this doable?

[rbh]

A few years ago while sitting around my buddys kitchen table, he told me how he had almost lost his life earlier that winter when he went to remove some snow from the top of his hay bales and the tarp gave way and he almost dropped into the center of a hay oven as the bales had started to combust do to the heat that was produced due to the moisture content and the way they were put up.
So one of the things we pondered was could you duplicate this with large round bales slid vertically into an inground galvinized pipe/tube/culvert and insert a heat exchanger of some type to move liquid from the heat of the hay to radiators through out the home/shop?

 

[Cofe]

Re: Farmers/chemists-is this doable?

Probably could be done, but the heat/air supply would have to be regulated precisely somehow. Then some method of ash removal would be needed. The bales your buddy just about fell into were on the verge of spontaneously combusting. Eventually they would flame......
Too much trapped gas from smoldering material could explode.

 

[MTboatguy]

Re: Farmers/chemists-is this doable?

I am neither, but I can say, over the years, I have seen some pretty amazing things happen with hay bales...

 

[rbh]

Re: Farmers/chemists-is this doable?

I guess the bales were put up about 30'x30'x30' +- and about 1/3-1/2 of the bottom-center was burnt or burning.
I guess between the top 2-3 layers that did not collapse into the fire and the tarp with the snow on it kept the air to combustion ratio down.

 

[Tim Frank]

Re: Farmers/chemists-is this doable?

The thermal content of hay (especially wet) would not make it a particularly effective source of heat.
The thermodynamics don't work.

 

[puddle jumper]

Re: Farmers/chemists-is this doable?

I have seen some nice barns go up in smoke from that. The hay was non stacked properly to allow for air movement throughout the hay stack.

I think what you are trying to do would be risky. The controlled burn would be the hard part.

 

[rbh]

Re: Farmers/chemists-is this doable?

Cap the top and have an adjustable vent to the center of the mass.

I have seen large piles of wood chips catch on fire and smoulder for months due to that type of internal combustion.

 

[Tim Frank]

Re: Farmers/chemists-is this doable?

http://wa-hay.org/publications/Spontaneous Combustion in Hay Stacks.pdf

Good article on spontaneous combustion of hay bales.

If you are a farmer, hay could be a viable heat source even though the weight/volume/heat content are not favourable.
These guys seem to have done it.

http://www.joplinglobe.com/local/x2...furnace-that-burns-hay-to-heat-poultry-houses

 

[CN Spots]

Re: Farmers/chemists-is this doable?

"If you are a farmer, hay could be a viable heat source even though the weight/volume/heat content are not favourable."

I wonder if they couldn't shred the hay, combine it with a binder and compress it into a giant fuel pellet to better manage the burn rate? It's done w/wood.

 

[rbh]

Re: Farmers/chemists-is this doable?

http://wa-hay.org/publications/Spontaneous Combustion in Hay Stacks.pdf

Good article on spontaneous combustion of hay bales.

If you are a farmer, hay could be a viable heat source even though the weight/volume/heat content are not favourable.
These guys seem to have done it.

http://www.joplinglobe.com/local/x2...furnace-that-burns-hay-to-heat-poultry-houses

Good stuff Tim-
Our thought was at the time to stack 3-4 big round bales (3rd cut in the fall) on end in the culvert, insert a combo air inlet/heat transfer pipe down the center to the bottom, get the pile smouldering to about 275 degrees +- and let it go for as long as it would burn.
Although not as dense as wood or pellets, the shear volume of hay smouldering should last quite awhile.

 

[wifisher]

Re: Farmers/chemists-is this doable?

It would not be cost effective. 3-4 bales would not have enough heat to make any real difference in heating a good sized building. Most of the heat would be lost to the outside through the culvert.

The reason that bales spontaneously ignite is all of the insulation around them. If the hay is baled too green, it will start to decompose. The decomposition creates a small amount of heat, which is trapped in the center of the pile. There is not a lot of energy being created. It just can't escape.