When I was working, I was involved in wood chip burning and I remember one
company was working on a small fluidized bed but I do not know if they ever
finished the project. The problems that you mentioned seem to be common to
the stoves. I am looking for a furnace, a corn burner or stoker in a
boiler. The underfed system seems like the best design to me. The corn
comes in from the bottom pushing everything up and the clinkers are pushed
out of the pot. I know in the wood chip burners, the underfed was one of
the best design and less trouble. There is no dealers around here so I am
limited to looking on the web. Some pots seem to have the air holes around
the top of the pot and other seem to have them part ways down the pot. It
is something that I will have to experiment with so the prototype will
probably be fairly light steel, as long as it would last a few weeks. Once
I would have a good design, I would probably get a pot casted in cast iron.
It is hard to see the details from small pictures on the web.

Thanks guys for the input and I would appreciate any other information.

Eric
"Karl Townsend" remove .NOT to reply wrote
in message news

Has anybody build their own corn burning furnace or has some of the
details,
like size of fire pot, air holes size and placement. I am interested in
an under fed system. Any other details that I have not listed would be
appreciated.

A number of folks in my area have copied the design of corn stoves for
sale. I seen a really nice one at the MN state fair last summer. Three
problems have cropped up with the stoves I'm aware of:

1. Heat cracks and bends the agitator fingers. This could be solved by
using only 304 SS for this component.

2. Ash buildup is a serious problem. Daily cleaning is required with some
lots of corn. Combustion efficiency goes to heck when the air holes are
plugged. Oyster shells have helped, but not enough.

3. Most units only produce 50,000 BTU on a good day, too small a heat
source. You'll still need a backup.

I was talking this over with a friend last fall. Someone should look into
building a unit that works like a coal boiler: Grind the corn up, feed
into a firebox with a strong air flow from below. This is called a
fluidized bed. The ash goes out the stack. Making a working design small
enough would be the biggest challenge here, most commercial coal unit are
for 1,000,000s of BTUs

Karl