burning sawdust for heating

[myxpykalix]

I started this so as not to overtake the "dust extractor" thread. I am kind of interested in this subject but to be able to heat the water in my hot tub. So please continue your talk here...

Mark I have seen homemade "rocket stoves" which slowly burn fuel very hot and it sounds like your pellets might make good fuel?

[adrianm]

What I've got for my hot tub is a Chofu water heater. It can't run on just sawdust but I quite often use it with sawdust once I've got it going with normal wood.

http://www.islandhottub.com/woodhtr.html

I know some of the woodshop stoves that are designed to work with sawdust are coming out with back boilers to run a radiator. I expect one of those could be adapted for a hot tub.

http://www.thehotspot.co.uk/Products/Relax_workshop_Heaters/RELAX_Woodburning_Workshop_Boiler_Stoves.asp

[mark_stief]

Jack There pellet fueled boilers out there but I don't know that they are low enuf in BTU's to do what you want to do the pellet I make are 1/4" in dia. and 1/2 " to 3/4" long just like you buy from the big boys for pellet stoves I have 4 pellet stoves to feed in the winter and sure beats giving the sawdust away in the summer time plus I have my grove of evergreens covered with about a foot of sawdust on the ground and they just love it good place to find worms for fishing too

[danhamm]

Both the house and shop are wood heated,the house has a exterior wood fired boiler and the shop makes use of all the sawdust we create and some waste oil mixed with wood dust.. works very well

[jhedlund58]

Smokey...bet u get a little blackness out of the oil?

[steve_g]

In the mid 60's I worked summers for a large window manufacturer (Anderson). They filled boxcars full of sawdust all summer and Heated the HUGE plant in the winter with it. They also had a humongous air compressor that ran off steam generated by the boilers. I remember watching the sawdust being injected under pressure into the firebox, a noisy and impressive operation! I don't know if they still do it that way, but was curious if any one else used that method on a smaller scale today.

Steve

[danhamm]

Actually no, its a Hunter 3 pass with secondary air, oil mixed with sawdust burns clean in it...But my nearest neighbours is my daughter and she is 2 + miles away..so not to worry...

[Brady Watson]

They sell sawdust heaters in the USA...and Mother Earth News has plans on how to build one somewhere...

-B

[Xray]

I made one some years back as a camp stove. Worked very good.
You can make one of out any metal can, or you can use double 55 gallon drums if you want some serious heat.
I like the idea of it for garage heating, in my case though, I'd have no where safe to put such a beast. I think the real challenge, when used for space heating, would be coming up with a way to efficiently circulate the hot air.
Here are some plans for a simple drum heater/cooker
http://nrs.fs.fed.us/pubs/rn/rn_ne208.pdf

[As a side note, I save my sawdust, but not for heating. I use it to have fun with at campfires in the summer. You throw handfuls of it into a campfire, and it just whooshes right up, and puts on a great light show. Kids love it, so do drunk adults.]

[adrianm]

I've just got a 12" electric fan positioned a safe distance behind mine. That pushes the heat through the workshop nicely.

My workshop is pretty small by American standards though (10m x 4m).

[kevin]

When I open my new shop 4 years ago .I planned on putting a wood stove in the middle of the shop .I even brought wood from my old shop that I saving for.So I needed comerical insurance they told NO you can.t have a wood stove in a cabinet shop I tried to find another insurance company its hard to get quotes I.am in a small market .
I use solar with the can it works well .I spent a lot of time and money on insulation .Average temputer 30 f or -2 c cost 1400 a year in oil 4000 sq ft shop

[kevin]

I mean who wouln.t want to use saw dust /I use it now as land fill compost heap

[jhedlund58]

most my sawdust goes to local farmer. he puts it outside his barn where the horses track in muddy soil. firms up the dirt fine for him.... he doesn't take anything with walnut in it... makes him mad.... and the horses too!!!

as u can c... i have more saw dust than i know wat 2 do with... thank you for posting about these heaters... i c 1 in my future

[GioAttisano]

it's a laborious pain in the ass, but I burn most of my winter dust and shavings in my conventional woodstove. You need a bed of coals, and then the dust is burned in large paper grocery shopping bags.It burns very hot and fast, and with a bed of coals in place I can burn bag after bag, preserving the coals beneath. I have a sort of dust chute made from a large cardboard box mounted on a wall in my cordwood shed that holds about 100 gallons with a tapered bottom and blast gate at the bottom. I can fill bags using this set up fairly quickly. I used to even save the bags all summer, but now I use summer chips to mulch our blueberries.