burning green chips in OWB

[Collin Miller]

I received an inquiry the other day which I had no answer for...Is burning wood chips from land clearing activities in a Central Boiler OWB doable? If the answer is yes, how can this be done efficiently and is there a small OWB on the market that will accomodate chips for heating buildings under 20,000 square feet?

 

[Nofossil]

I received an inquiry the other day which I had no answer for...Is burning wood chips from land clearing activities in a Central Boiler OWB doable? If the answer is yes, how can this be done efficiently and is there a small OWB on the market that will accomodate chips for heating buildings under 20,000 square feet?

There's a company here in Vermont that makes an industrial chip burner that will burn green chips. I believe it dries them first, though. I don't know any way to burn green wood efficiently on a residential scale.

 

[heaterman]

I received an inquiry the other day which I had no answer for...Is burning wood chips from land clearing activities in a Central Boiler OWB doable? If the answer is yes, how can this be done efficiently and is there a small OWB on the market that will accomodate chips for heating buildings under 20,000 square feet?

Probably not do-able with a typical OWB. Industrial sized boilers that burn high moisture biomass (>30% moisture) almost universally use fluidized bed burn technology which is the polar opposite of a typical OWB.

 

[waynecub]

Collin
The company in Vt. that builds a wood chip gasifire is Chiptec. The chip systems that Chiptec builds start a 1 million BTUs and up.
The school that i work at has one of there systems. It's a 3 million BTU hooked up to a 90 hp. Boiler.
The trees are chipped and brought to the school to be used that day. The gasifire is all brick and refractory lined. Inside the gasifire the temp. is so hot that the chips dry very quickly. See chips will dry fast because of there size, not like chunk wood.

There are 3 kinds of wood chips
1 Mill chips ( the chips are a sawmills wast ) no fines
2 Bowl chips ( this is all of the tree except for the crown ) usually chiped up on the landing
3 Hole tree chips ( This is all of the tree crown and everything ) usually chiped up on the landing

Our school burns bowl chips.

I looked into burning wood chips on a small scale not easy. But it can be done.

Marcus

 

[pybyr]

Collin
The company in Vt. that builds a wood chip gasifire is Chiptec. The chip systems that Chiptec builds start a 1 million BTUs and up.
The school that i work at has one of there systems. It's a 3 million BTU hooked up to a 90 hp. Boiler.
The trees are chipped and brought to the school to be used that day. The gasifire is all brick and refractory lined. Inside the gasifire the temp. is so hot that the chips dry very quickly. See chips will dry fast because of there size, not like chunk wood.

There are 3 kinds of wood chips
1 Mill chips ( the chips are a sawmills wast ) no fines
2 Bowl chips ( this is all of the tree except for the crown ) usually chiped up on the landing
3 Hole tree chips ( This is all of the tree crown and everything ) usually chiped up on the landing

Our school burns bowl chips.

I looked into burning wood chips on a small scale not easy. But it can be done.

Marcus

there was some fellow in far southern VT who had a web site that I was looking at in Spring '08 who claimed to have made a home-brew, home-scale downdraft chip burner (using a design that had a vertical column of chips, burning from the bottom) who claimed it worked great with green chips. I'd even sent him a note at one point, but did not hear back. Perhaps someone can find him again with Google. The concept seemed sensible, and I have heard of other similar designs that have been tried- but they don't strike me as anything that one could leave unattended, or have in any sort of occupied building or a building anywhere within fire-catching range of an occupied building.

 

[pybyr]

I received an inquiry the other day which I had no answer for...Is burning wood chips from land clearing activities in a Central Boiler OWB doable? If the answer is yes, how can this be done efficiently and is there a small OWB on the market that will accomodate chips for heating buildings under 20,000 square feet?

this is pure "thinking out loud"- not anything that I am recommending, but what about one of these, or something similar burning chips, and using the wood gas to feed a "gas nozzle" pointed in through a hole in the firebox door of the OWB?

http://www.allpowerlabs.org/gasification/gek/

?

 

[JustWood]

Chips wood work between layers of wood. My dad (has CB 5036) puts in several layers of slabwood then 2 snow shovels of sawdust then more wood and so on till full. The trick is to have air flow between layers of sawdust otherwise the dust will choke itself out.

 

[DenaliChuck]

Someone here sent me a file with an update of a guy that has converted his Tarm Solo to burn wet woodchips. If I recall correctly, he is a retired mechanical engineer and his setup is impressive. Apparently he heated his house in 2006...don't have any more up to date info than that.

PM me and I'll happily share the file.

Maybe someday I'll have time to attempt this. It would be a great way to use a waste product to heat the house and be one step closer to carbon neutral! Maybe someday.

DC