does anyone know the heat output of sawdust ?

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big-all

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i have loads of sawdust that i can burn in my wood burner but it needs to be bagged to stop explosion
its around 98% softwood including ply and mdf with the rest being oak iroko and beech
a bag costs around 1p and possibly 50-100grams off sawdust so the possible 15p a kg off sawdust must give more than a kw off useable heat or not a worthwhile option as opposed to a fan heater at say 95% efficiency at 15p a kw
thanks for reading and your answers :D
 
IIRC it is possible to make briquettes with a tiny amount of cement and water added to the sawdust, well compressed, and left to dry after curing.

Have never done it myself but my old dad told me about it; also briquettes from coal dust and smalls made the same way.

Otherwise the fire will tend to damp down and burn badly.
 
thanks jd
i probably produce 1-1.5cubic metres a year so a low cost option is essential
if i need a compater at say £12 it will take several years to pay its way
 
Is that the heat output with or without the slumbering gerbils?
 
I believe you shovel the mix into a grid of boards into brick-sized pieces, and tamp it down. Quite a low-tech method. 1950's back-yard technology.
 
I'd be interested to hear just how big the explosion risk is...I produce a similar amount of sawdust to you Big-all and I wrap mine up in newspaper like Christmas crackers. It's cheap and I've never had a problem (yet!).
 
I would have thought the risk of 'explosion' would only be an issue with a volumous amount of sawdust that is well compacted with a limited amount of air. If volumous and well compacted I can imagine the sawdust would slowly start to ignite internally, and 'explode' as the need for more oxygen grew. It's a bit like opening a door into a room that is well ablaze -oxygen will feed the fire.
 
its the large surface area means the sawdust burns instantly releasing all the energy at once

light a candle then throw a spoonful off sugar or flour or sawdust onto the flame from about 2ft and watch the reaction compared to spoon on at an inch above

dont buy newspapers and no freebies delivered round here
and resort to several pages off tv choice to light the stove
 
ImayKnow said:
I would have thought the risk of 'explosion' would only be an issue with a volumous amount of sawdust that is well compacted with a limited amount of air. If volumous and well compacted I can imagine the sawdust would slowly start to ignite internally, and 'explode' as the need for more oxygen grew. It's a bit like opening a door into a room that is well ablaze -oxygen will feed the fire.
Click to expand...

Even Joe is smarter than that !

Never had much success burning sawdust in a fire, tends to smother everything else and goes out.
 
you got an old potato chipper hiding in your cupboard,just wondered if you could modify it to make sawdust chips?
 
gregers said:
you got an old potato chipper hiding in your cupboard,just wondered if you could modify it to make sawdust chips?
Click to expand...
yes i have
i wonder if i could use it to compress the dust with a small amount off binding agent [maybe soaked in a flour or sugar solution] :D
 
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