Pelleting charcoal

So I was thinking the other day the problem with charcoal is its low density. Wuld it be posible to compress it and make some sort of pellets out of it? Has anyone tried this?

My hard wood charcoal has a density of about 0.3g/cm3. I milled it to a corse dust grade and aded about 10% water and 1% flour to it. Pressed it in a cilinder with a hydraulic grape press and dryed the pellet. It had a density of about 0.55g/cm3 so i was able to almost duble the density. If it wuld be posible to make this on a large scale i think that wuld be a great advantige for a small comact charcoal gasifier.

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That sounds like an interesting experiment. I would like to hear how they burn. It sounds a bit like store bought charcoal junk, powder and binder compressed. Next question is how much energy and time will go into making these? is there a net energy gain when that is considered?

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What I’m curious about is what do you want to use it in? Charcoal gasifiers are usually up draft and the extra ingredients would probably gum up the machine. Just friendly question is all
David Baillie

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The comercial briquetes are indeed crap. They also have a lot of unchared sawdust in them to make them heaviet so that is a no go.
My pellets burned just the same as pure charcoal but the only drawback is that they spark a lot and are a bit to britle. I shuld maybe ad more binder (starch) to them.
I have a crossdraft gasifier so i thing a few % of starch shuldnt be a problem althugugh i agree with you that a updraft sistem may not work.
I was thinking of a sort of extrudor mashine where an auger pushes the mix trugh a plate with ~10mm holes in it. All the peaces wuld be the same size and there is no waste of charcoal like when you size your fuel for a gasifier.

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Personally I put it in the composter so there is no waste but I get your point. If I had to use the dust I would starch it, compress it into a larger block with airholes and burn it in a stove for coozing or heating. There are a lot of NGOS working on things like that. I wish you luck though
David Baillie

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i have tried them… commercial made brand, gummed up all the filters right away…
do-able dough if you make them yourself… the better the quality, less problems…
about 2 % starch needed and water.
Then dry them, possible in a high temp oven, experimenting :wink:

Edit: forgot to mention…
Low density equals higher reactivity… advantage for good gasification…
so, if you compress, you loose that advantage.
high grade seeving and sorting worked best so far for me,

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You are right about the reactivity… Soft wood charcoal allways tends to work beter in my sistems thain hardwood char due to the biger surface area.
Just curious. Has anyone tryed coal or coke in a charcoal gasifier?

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Maybe I will give this charcoalpellets a try. For the moment I am still searching wich way to go. And that is not making pellets from woodwaste. Here are some pictures. I gave it a serious try a few years ago and managed to keep the house warm with home pressed pellets. It gave a kick just like woodgas (I hope). But if you want to make pellets in a realistic way, the press has to be 22 kW as a absolute minimum. Otherwise you are just smashing time and money. This installation is 7,5 kW and delivers 75 kg/h. That means you save 15 dollar an hour if nothing breaks and power is for free.
Anyway, we had fun but now it is time to make room for the Lister genset.
Bunkerbottom is square 6 foot and 12 feet high.

From here it goes to a hammermill 7.5 kW (it actual uses 3 kW or so) to get the right size for the pelletmill. Can’t find te mill at the moment but sawdust was dosed by the left round bunker. Dust flows over a magnet to capture metal. You dont want to be around if some falls in the mill!!!

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From hammermill it is blow to a cyclone on top of the square dosingbunker and from there via a screw fed to the mill.

Speed is adjustable.
Water is fed by a hosepump with adjustable steppermotor. Sawdust is normally to dry when it leaves the factory.

After the mill there is a shaker screen/transporter and warm pellets go up a conveyor.

After conveyor there is a last screen before pellets fall in a container.

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So , I made my hands dirty making pellets and I think I am allowed to say it is a dead end road unless you go BIG. Not for home use unless you want to smash time and or money. But what the heck, it is allowed that a hobby cost money.

For the moment every thing is pushed aside to make room for a genset.

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Joep,
I believe you have captured the promise and reality of making your own pellets, no matter what the pellets are made of. Anyone who believes making your own pellets is easy and cheap should carefully study and consider your recent posts here. :thinking: Thank you for sharing your experience with us :blush: PS: I like the 4 wheel vehicle in the first photo!

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Ha ha, yeah me too. We have two off them but they dont last very long. My daughteris very fanatic with them and bounced me off the road. LOL. Iwill post another link to YT. That when we go completely grazy. I forget that competitors are my children and bounce them away in a corner.

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75 kgs of pellets pr hour ready to run? Thats 165 lbs converted.

The average Joe chipping fuel would be lucky to produce 80 lbs of chips pr hour using a home and garden chipper and it would still need to be dried. With 50% or greater waste.

I have done all the calculations with this. Pellets are by FAR more efficient to produce. You must factor all into this equation all your waste all your energy inputs, drying energy everything. Not just taking it at face value.

Those that have large chippers or a PTO chippers would surely be able to produce much more. But that comes at a much higher expense.

165 lbs of pellets retail cost today is $22.68 here in the US.

My pellet fuel reactors are 20% for efficient than our chunk fuel reactors of the past. They produce 1 kW pr 2.2 lbs verses 3 lbs or greater of the old reactors. It cost you nothing to bulk feed pellets, verses you need a very powerful auger to bulk feed chip fuels. You need a minimum of a 2 hp motor, this over 2 kW energy input that is taking away from the system and they are constantly turning. This is part of equation, it energy lost in process.

Pelleting is a heat process that is built in, So indeed it looks slower than chipper blowing out chips. However pellets are shedding moisture while in process plus they are two times more energy dense.

All your waste from chips must be factored. Your energy input to produce that waste plus the waste itself and your time. This is huge thing Im not seeing people factor.

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Look how much smaller the first machine is compared to the older chip fuel versions. That smaller machine will run nearly 3 hours on single load of pellet fuel. Verses the old machines were just over an hour.

I would gladly feed that pellet mill verses trying to keep that old chip fuel machine full and running. Not just making fuel for it but even with my best efforts, the pellet machine runs nearly as stable as a gasoline generator. The chip machines were not even close them.

Yeah watch the chip machine to the end, it almost crashed. The pellet machines dont do this.

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Nice work Matt, but I rather compare it to Jo s rebak chunker. I love that thing.

No doubt that pellets are a beautiful fuel.

And prove that I am wrong, please, I don t have to be right. If I am wrong, I am wrong. As simple as that. No problem.

Heating is now done by a small woodgas boiler with pellets for backup. Electronics is almost clean. Funtioning already. Basics is with relais. Monitoring with arduino raspberry and domiticz. Cheap and I dont trust it. So, relais are just working and monitoring is via wifi. All new for me. I only can shout and smash hammers. So that was a steep learning curve. Today made some room for the lister. Veggie oil with small chunks or charcoal it has to eat. Didn t make up my mind. But it is coming.

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Actually I am agreeing with you. The issue is you think your labor is worth more than your pellet yield and have not factored in other methods with same ready to run fuel yields in this time allotment.

Go get yourself a lawn and garden chipper or find someone that has one and try it for yourself. Keep in mind you must chip all your fuel, fully sort it and screen it and yield ready to run fuel in one hour. Can you really produce 165 lbs of ready to run chip fuel?? You would be lucky to just chip that much!! I not only bet you cant I guarantee it!! I have and this is my basis on calculation, its not worth my labor when I can just buy pellet fuel. If you are only yielding 80 lbs, that is only $11 USD worth in pellet fuel. Its a ton more work then just shoving sticks through a chipper. You will have much more time involved processing and sorting it than just chipping it. And again all that waste is energy lost this is huge loss no one seems to be factoring. The energy and time to produce this waste, plus its energy potential that can not be used. If you use for drying process, then you have another piece of equipment; you might as well build a charcoal kiln if going to that extent.

Chunking is a different story and is not really my argument. One thing to consider is what I build and the criteria commercial machines must meet for them to be marketable. So seeing my stand point and where Im coming from is important to understand my argument here.

Chunking works and is a very efficient and effective way to produce fuel. However, I can not use chunks as there is no way that I have found to bulk feed it. This is a very big criteria most clients require. A one or two hour run time is not enough for them. Generally they want 8 to 16 hours of run time.

I have now revised the current machines to run on all fuels. All you have to do to run on chunks or chips is remove the pellet fuel carburetor. But then you go back to a primitive performing machine and will be limited to the straight lower capacity hopper as I will never ever produce an auger bulk feed system again. Its a day and night difference. I think most will convert the machines back once they figure out there is no smoke in the hopper, the machine runs cleaner, runs more stable, more efficient with nearly zero filter maintenance and much longer run times.

Back on topic, Torified pellets from a pellet gasifier are perfect ready to run fuel for charcoal gasification. So your energy input for pelleting can very easily be done with charcoal gasification.

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Today I got auger feed going to test flow switch . Flow switch failed had to pry wood chips out of gasifier .

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Can you read my mind? Just saw something somewhere. Dead simple and effective. I will post if I find it. Quite failsafe, simple switch and lever.

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Here it is.

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