compressed sawdust charcoal

[Toddy]

Didn't know quite what to title this thread

I recently bought blocks of charcoal for use in my tipi for heating and cooking. Though the blocks, each about 15cms diameter and about 5cms deep, are really cheap just now, 2 for £1 in Poundland, I know that once the seasons move I won't be able to get any more until next year.

Has anyone made their own?

I can get masses of fine sawdust from the boatyard, but how do I turn it into charcoal blocks?

When the coalman still came weekly he sold briquettes made from compressed coal dust that folks used to burn at the back of the fire to keep a slow heat going all night and make it easy to re-light the fire in the morning. What did they use to stick the coal dust together?

I can buy saltpetre so that ought to aid getting the charcoal block to burn but I still can't see how to make the block from sawdust in the first place.
Help or suggestions gratefully received.

cheers,
Toddy

 

[weekend_warrior]

you shouldn't need any binding agents - just dry saw dust, although some manufacturers use corn starch. Try using piece of steel pipe and a close fitting solid ramrod as a compressor. You'll need quite abit of pressure (>80lbs?), but you should get sawdust pellets that will burn well. Maybe hammering the rod might do it? Very labour intensive for each pellet though... and they'll need drying time out afterwards

 

[Toadflax]

This site might give a clue as to how they stick together: http://www.stovesonline.co.uk/what-are-wood-pellets.html.

"Wood pellets are usually made of compressed sawdust that is a waste product from other industries (e.g sawmills). The pellets are held together by the natural lignin in the wood - no glue is needed. Lignin makes up about a quarter to a third of dry wood."


Geoff

 

[tommy the cat]

My neighbour has just wired a machine he was telling me about at a local mill which turns sawdust shavings into blocks/ pellets. They then sell them at local farm stores not tried them yet although I think he said the machine was thousands!
d

 

[jon r]

why not just use normal charcoal

 

[Biddlesby]

Interesting info:

While some briquettes are made from a combination of charcoal (heat source), brown coal (heat source), mineral carbon (heat source), borax (press release agent), sodium nitrate (ignition aid), limestone (uniform visual ashing), starch (binder), raw sawdust (ignition aid) and possibly additives like paraffin or lighter fluid to aid in lighting them, other "natural" briquettes are made solely from charcoal and a binder. The charcoal briquette was first invented by Henry Ford from wood and sawdust scraps from his automotive plant.

Dunno if I'd want to cook over all that!

 

[fredcraft]

why not just use normal charcoal

I assume it's to re-use a ressource available in large quantity and to save some money. I think it's a good idea !

 

[EdS]

rather than charcoal you can use saw dust with a little papier mache as a binder. Then one of the those "log presses" to form them - but they take for ever to dry.

 

[Toddy]

Now that has potential .......so if I use sawdust, mix it with a starch like the stuff I use for papier mache.....I sometimes make the stuff from nettle waste......maybe add some saltpetre to encourage it to burn and then compress the stuff I ought to be able to dry it out and have neat, tidy, blocks to burn?
Only problem I can think of is the smoke. Charcoal doesn't give off much smoke since it's already pre-burnt so to speak.

cheers,
Toddy

 

[weekend_warrior]

Now that has potential .......so if I use sawdust, mix it with a starch like the stuff I use for papier mache.....I sometimes make the stuff from nettle waste......maybe add some saltpetre to encourage it to burn and then compress the stuff I ought to be able to dry it out and have neat, tidy, blocks to burn?
Only problem I can think of is the smoke. Charcoal doesn't give off much smoke since it's already pre-burnt so to speak.

cheers,
Toddy

I'd leave out the saltpetre - maybe a dab of liquid parrafin though as extra binding?

 

[Toddy]

I'm not keen on burning paraffin, a refined petro chemical, but saltpetre can be made if necessary

http://www.salt.org.il/saltpet.html

http://atlas.kennesaw.edu/~rbentley/notes_on_making_saltpetre_from_the_earth_of_the_caves.html

I'm kind of aiming for diy using waste materials if possible.

cheers,
Toddy

 

[Eric_Methven]

Making charcoal out of sawdust is nigh impossible. As you know, charcoal is made from burning wood and by excluding air once the wood is hot enough to sustain full charring without combustion. You also know how fragile charcoal is once made. It is basically the structure of the original timber keeping it together. You lose that structure once you make sawdust.

Making briquettes from sawdust works, with or without a binder. Once you throw a load of briquettes into a charcoal kiln and light it up, it will burn, and when you close the burn down, it will char. But when it's cold, and you open it up, you have powder.

There are hundreds of charcoal burners all over the UK with sacks and sacks of charcoal dust that they can't get rid of. Since the gunpowder industry no longer exists, it's no good there. The industry using charcoal for filtration uses specially prepared charcoal, and these guys are stuck with the residue from their burns. They are known as 'fines'.

There are machines you can buy to compress the fines with the addition of a binder, and that's what you get when you buy charcoal briquettes, but the machines are not cheap, and as most burners work out in the woods with a kiln that gets moved around as an area is worked, a briquette machine is not a viable option for them.

So, it is possible to use charcoal dust and small particles to make briquettes, and it is possible to make wood briquettes from sawdust, so it should be possible to make the sawdust into charcoal dust, then bind and compress the dust into charcoal briquettes.

Seems like an awful lot of work to me, especially as the end product will be approximately one third of what you start with.

Eric.

 

[Toddy]

Hmmpph

Thanks Eric, it seemed a good idea too. Ah well......

Here, there's a thought. In rural Egypt open pottery kilns are fired with charcoal but towards the end of the burn a wheen of sorghum chaff is thrown in and this burns off any extra oxygen and gives a further heat boost to the firing. I can't remember why this is considered a 'very' good thing, but it seemed terribly important to the archaeology ceramics lecturer at Uni Could those 'fines' you mentioned be combined into something practical that could be used for pottery firing?

atb,
mary

 

[Tadpole]

Didn't know quite what to title this thread

I recently bought blocks of charcoal for use in my tipi for heater and cooking. Though the blocks, each about 15cms diameter and about 5cms deep, are really cheap just now, 2 for £1 in Poundland, I know that once the seasons move I won't be able to get any more until next year.

Has anyone made their own?

I can get masses of fine sawdust from the boatyard, but how do I turn it into charcoal blocks?

When the coalman still came weekly he sold briquettes made form compressed coal dust that folks used to burn at the back of the fire to keep a slow heat going all night and make it easy to re-light the fire in the morning. What did they use to stick the coal dust together?

I can buy saltpetre so that ought to aid getting the charcoal block to burn but I still can't see how to make the block form sawdust in the first place.
Help or suggestions gratefully received.

cheers,
Toddy

can you burn "fireplace logs" in your fire?
they are made of wax (any kind) sawdust, charcoal, pressed into log shapes and left to harden. I'm told that well dried coffee grounds added to the mix helps the burn and increases the heat

 

[oops56]

Well its a small world i did it here is the results. I used sawdust from my table saw.On the left sawdust & little fine bees wax. the one in the middle sawdust newspaper done in a blender. last on just sawdust. My press top left just a c clamp a piece of plastic pipe with a fender washer to fit with holes to let water out as you press.Put as much as you can put out in sun to dry takes one day to dry Oh you mix with water just like past.



this is about 1 min put just a little alochol to get them fire up

 

[Eric_Methven]

Hmmpph

Thanks Eric, it seemed a good idea too. Ah well......

Here, there's a thought. In rural Egypt open pottery kilns are fired with charcoal but towards the end of the burn a wheen of sorghum bran is thrown in and this burns off any extra oxygen and gives a further heat boost to the firing. I can't remember why this is considered a 'very' good thing, but it seemed terribly important to the archaeology ceramics lecturer at Uni Could those 'fines' you mentioned be combined into something practical that could be used for pottery firing?

atb,
mary

Yes, but getting them to rural Egypt would be too expensive to make it viable

Eric

 

[Toddy]

I supposed I asked for that one, hmmm,
How about rural UK ? D'you think the stuff could be used in firing pottery? We've got masses of sawdust; the extractor system in the workshop sometimes fill three of those tonne builders merchant type sacks a week.

cheers,
Mary

 

[Eric_Methven]

The sawdust could certainly be used in firing pottery, on an amateur or primitive scale. In fact that's what was used in times past. I've done it in a big metal dustbin before and it gives great results as you get loads of heat and no oxygen to speak of, so the finished colour of the pots is uniform. It won't work with charcoal fines though. They are best for making black powder and there's no way that's viable without a heap of licences a mile high. The pottery with sawdust is certainly an option though.

There's a good book here.

Eric

 

[Toddy]

So, theoretically......if I packed a tin tight with the sawdust, something like a dried milk tin with a press on lid maybe or one of those big sweetie tins from christmas; could I set that on fire to heat the tipi and give me a something I could cook on too?
How do I start it burning without an oxygen source?

cheers,
Mary

 

[Eric_Methven]

I wouldn't. The smoke will drive you out. Possibly if you mixed the sawdust with beeswax so the sawdust acted as a wick and the beeswax controlled the rate of burn it might work, but there's better ways to use sawdust (firing pots as mentioned above). You'd need to experiment first.

Eric