Make Your Own Charcoal Briquettes

According to how Daniel O'Connor describes it, charcoal making is slow but easy work. There are two ways to make charcoal direct and indirect.

The direct method involves setting a pile of wood on fire and controlling the air intake in order to char the wood and not burn it into ash, e.g. by covering the pile with dirt and sod.

While the indirect or retort method involves cooking the wood with a outside energy source to drive off the volatile gases and char the wood. The indirect method usually yields more charcoal for a given amount of wood. Even though an outside energy source (a fire) is needed in the beginning, the process can be made self sustaining after a short time.

The expelled volatiles can be distilled to produce products like turpentine and wood alcohol, which was done prior to the petrochemicals industry. Or the volatile gases can be diverted to make the process self sustaining.

It is simple in concept and execution. The wood is heated until it starts giving off gas. Route this gas back under the container and ignite it. Once this is happening, the wood gives off enough energy to 'cook' or char itself. When all the gas is driven off the the fire dies out and charcoal remains.

A pipe from the top, in the above contraption, is routed under the barrel. The pipe below the drum has 1/2" holes drilled every 6" along either side of it. Under the above two barrels, loaded with cut wood and sealed, a large fire underneath takes 45 minutes before the emission of volatiles begins.

As the gas yield starts, flames begin expelling from of the holes drilled in the bottom pipes. In about 5 or 10 minutes the flames become like pressurized gas and if the drums are enclosed (e.g. within concrete blocks) they will shoot out the holes, hit the side walls and travel up and around the barrels. The fire dies on its own after about 2 hours, and the charcoal is let cool down overnight.

Find complete instructions from Mr. O'Conner until I can get my plans drawn up for download.

While searching for a set of plans for one of my visitors I ran across a new posting in some of the forums by a fellow who built a charcoal furnace from a chocolate tin. You know a small tin about the size that the Christmas Danish Cookies come in?

Punch five holes about 1/2 inch in diameter in the lid. Chop your small sapling into sizes that will stand in the tin; floor to lid. Arth from BushcraftUK used Ash because of its low water content, it cooks out quicker. Stack them standing up but don't compress them too much. Set the tin on the campfire until the large flame that comes out of the five small holes burns out, then smother the lid by pulling it from the campfire and flipping it upside down on the grass or sand. Let stand for about an hour or so, until tin is cool to the touch.

Now open the tin and use your easy lighting charcoal. This charcoal will not need any lighting fluid and it will be enough for a cook out for over 10 people as well as lasting much longer.

So don't throw away your old tins! I can see this method being used as a survival method in cold environments!

Thanks to Arth from the BushcraftUK Forum for the cool idea and the awesome pics!

You should know me by now.

I'm not just going to point to someone's work and say that's it.

Now with me, I'm not just thinking the cooking charcoal here. I'm an artist too. Some refinements to the way you would combine the ingredients could extrude some really nice charcoal pencils. Or just char up a good batch of grape vine. Again, you could manufacture these with just limited knowledge of making pencil barrels.

Also, there is the heating perspective. Both the charcoal, and the charring process for the leaves, paper, etc., could be used to heat a home during the winter months. Which incidentally is just after we have collected all of those leaves from our lawn, unless you're like me and allow the leaves to insulate the ground from the winter mix.

Besides, I'm also not just talking about leaves here. Just about any bio mass will work. Thailand and several other countries use sugar cane refuse for charcoal production. Island nations use coconut shell. Like I said, wood chips, paper, cardboard, corn cobs/stalks, lawn trimmings, hedge trimmings, tree trimmings, old pallets, and even saw dust can be used in this process.

I like the simplicity of the Indian kiln, but I think that is still wasteful. A properly aerated kiln about the size of a gallon paint can is being used in the youtube video below, to generate 10,000 BTU of heat or the gas can be collected as a methane/HHO/carbon monoxide gas combination which can be used to even power propane prepped vehicles. You can use the charred ash for your charcoal. You can use the heat in the kiln to heat your house/garage/shop. And after you have used the charcoal you can use the ash in your compost to stabilize your fertilizer's pH content. How's that for being Green?

Oh, and - If you were to use the Indian kiln you would have the typical smoke. If you used the kiln from the youtube video, the smoke is negligible therefore cutting down emissions that much more.

Image Courtesy showroom411.com

An organization in India ARTI has written this article:

"Urban solid waste consisting of leaf litter, trimmings of trees and hedges, and paper waste can be charred in this kiln. The kiln consists of a steel barrel provided with a chimney. The barrel is filled with leaf litter. The leaves are ignited from the top and then the chimney is placed over the barrel. The leaves are allowed to burn for about 20 minutes, after which the chimney is lifted off and water is sprinkled on the burning leaves to extinguish the fire. Both the chimney and the barrel have been provided with handles for convenience of operation.

After extinguishing the fire, the barrel is upturned on the ground and more water is sprinkled on the char to extinguish it completely. The emptied barrel is filled again with fresh leaves to start the process all over again.

Each batch takes a load of about 6 kg leaves and it yields about 2 kg of char per batch. In a day, one operator can complete 16 batches to obtain about 30 kg of char.

The char is mixed with starch paste (made from waste cereal flour) and extruded into briquettes. If one person in the family operates the kiln and another operates the hand operator extruder-type briquetting machine, the family can make daily about 35 kg briquettes.

The briquettes are dried in sun. The 30 kg char with the added weight of about 3 kg cereal flour, ultimately yields about 35 kg briquettes. The briquettes can be sold as domestic fuel. Selling a good portion of the product can be a decent income.

Do's and Dont's:

- The leaves should not be packed tightly into the barrel, but filled only loosely.

- The barrel has holes at the bottom to let air into it. Therefore, the barrel should be placed on three bricks to avoid blockage of the air holes.

- Keep a water filled hose can handy to sprinkle water on the char and also to sprinkle water on any other objects that may inadvertently catch fire.

- Char should be fed into the extruder with the help of a large ladle. Do not feed the extruder with hands because fingers may get crushed if they come in contact with the worm screw in the extruder.

You've charred the carbon based refuse. And unless you used the very top process with solid chunks of wood and or old shipping pallets, have a powdered char product. You have added the flour/waste flour/cereal flour (somebody tell me if the aromatic saw dust [hickory, mesquite, cherry, apple] works, I haven't had a chance to try it yet). Now you don't want to kill all of your savings by buying some huge 3-phase monster that you might get an arm chewed off in...

How about a home-built extruder? "You can do that?" Sure! An MIT student in 2002 used it as her thesis project.

The first attempts could be used on an on going basis if you weren't using them much. They were based on a meat grinder type system, built of wood and PVC plastic, and were crank powered by hand.

Her final assembly looked more like a cement mixer. A funnel emptied to the screw and extruding tube. The extruding screw was hand powered by turning a large wheel, built much like a bicycle sprocket assembly. A simple machine that produced a long term, and low cost method to making your own charcoal briquettes. (You can still download the movies and presentation PDF at, MIT.edu) Her thesis was based on bringing new fuel ideas to third world countries.

Then, drop your briquettes in the sun, or even better use a solar oven to dehumidify them.

Depending on your mix, you should have some clean burning, long lasting, briquettes, that you could soak in a hardwood pulp (saw dust slurry of hickory, mesquite, or other aromatic hardwood) and re-dry for that smoked flavor. Or soak them in mild potpourri solutions (my favorite: cinnamon and eucalyptus) for a very cheap take on air-fresheners, which also can help clean the air, but that's another lens all-together.

Or you can do what the commercial guys do and soak them in lighter fluid, but you would be surprised to find out that the product you have created burns and lights very easily. Besides, we all hate that taste of lighter fluid in our food when we rush our cook-out don't we?