Backyard Biochar This site has descriptions of my experiments with Flame Cap Kilns. I also report on work by others.
US Biochar Initiative I am on the advisory board of the USBI. We are sponsoring the 5th North American Biochar Symposium in Corvallis, Oregon - August 22-25, 2016
Illinois Valley Forest Collaborative I've been involved with the group in my hometown for several years. We are working with the US Forest Service on hazardous fuels and small diameter timber sales. Biochar is a part of what we do.
Umpqua Biochar Education Team (UBET) I am working with UBET on a Conservation Innovation Grant from the USDA-NRCS. We are helping small farmers learn how to make biochar and use it to manage manure and make premium compost.
The Dome School Biochar Project Wiki Here you will find photos, reports and lesson plans I developed for a semester-long biochar curriculum for elementary school students
Kamal Rashid, CEO at Zanjabil Gardens in Pembroke Township, Illinois, has made a giant cone kiln. Last month he completed his first full test burn in the kiln, which has a 59" top diameter, a 24" bottom diameter, and is 24" high. The kiln made 133 gallons of biochar (17.7 cu ft) in about 4 hours, using cordwood. Kamal reports that it took 30 gallons of water to quench the kiln.
Kamal is also an officer of the Pembroke Farming Family Association, and he helps with technical assistance to other farmers. Kamal is very happy with the cone kiln, which was fabricated by a local community college welding class. You can bet he will be helping other small farmers in his area get started with making and using biochar. Here are some of his pictures:
My pal Michael Wittman is a real Biochar spark plug! In January he initiated the cone kiln at the Simi Community Garden. And that was just the beginning for Michael. Here is his first video:
Josiah Hunt has been doing commericial biochar longer than just about anyone. He is perhaps the finest example we have of small scale, low tech biochar entrepreneurship. Being in Hawaii helps - he has abundant feedstock, abundant need (poor tropical soils subject to leaching rainfall) and an educated public of permacultural farmers who get it. But despite the advantages of location, it was Josiah's genius that drove him to invent an economically sound biochar production method that allowed him to actually start a business. Not only that, his method is pretty clean, unlike traditional charcoal pits that smolder wood for many days and emit methane and carbon monoxide. In the open pit method, these gases are burned off so there is very little smoke.
Josiah uses a pit. No metal cone required. His method of gradually adding new wood over glowing coals is exactly the same method as the cone kiln. One difference is, he quenches with dirt instead of with water. Here is the link to his description of the method, with pictures:
The volume of the cone kiln is about 35 gallons (or about 4.5 cu ft). The yield of biochar pretty much equals the volume. I usually have to toss out a few brands (incompletely charred pieces) but not many. One secret to maximizing the yield is to finish off the burn with small stuff like twigs or a couple of buckets of wood chips that burn quick and hold in the heat to finish charring the bigger pieces. Of course the volume of char is reduced by half at least (have not measure it yet) when I run it through the compost shredder to turn it from chunks to powder. Anyway, here is what 35 gallons of chunks looks like:
Here are quick specs on the cone kiln if you want to try making your own: It was made from a 4x8 sheet of 14 16 gauge steel with 3/8" rod welded around top and bottom rims for stability. Top diameter is 43". Bottom diameter is 16" and height is 16". It is open on the bottom so you just roll it away when you are done. That's it. My welder had a heck of a time bending the steel to make the seam weld. Needs a couple of strong guys or preferentially a differential slip roller to roll the form into shape. You could also make it from lighter weight steel.
Here is a paper that looks at biochar characteristics produced by this type of kiln. And here is a marketplace where you can buy one of the Japanese kilns. They are stainless steel, I believe and they come in different sizes. The 100 cm kiln is very close to the size of my version.
I love my Japanese Cone Kiln. I had a welder make it for me 2 years ago, but I did not understand how to use it. I finally figured it out about a month ago and it is so easy! It is basically just a cone-shaped fire ring - a truncated cone. All you do is start a small fire in the bottom, and once that is all burned to glowing coals, you add small stick wood or branches on in layers. Each time the wood gets black and starts to ash, you add another layer. The layers underneath continue to cook out tar and gas, but they don't burn because air is excluded. When the cone is full you quench it with water. If you like, you can throw a grill on it and cook your dinner before you put it out.
It takes about 2 hours of very easy work. You can do other chores (like splitting wood) while you watch the fire. And the yield is very impressive. I start with two 6 cu ft wheelbarrows full of 2" kindling wood. I end up with about 5 cu ft of nice, crumbly biochar (water quenching really helps make your biochar hydrophilic).
Compare this with my JRO (Jolly Roger Oven) TLUD and my retort kiln, both using 55 gallon drums:
My JRO TLUD takes about 45 minutes when loaded with big wood chips. The yield is about 2 cu ft. Finding, screening and drying wood chips is a pain. And the tall stack of afterburner and chimney is hard to handle for me (at 5' 2" I need a step ladder).
My retort kiln takes about 2 hours to complete. The yield is about 1.5 cu ft and I usually use about one full wheelbarrow load of wood to fire it, sometimes more. The feedstock prep is similar to the cone kiln, although I can use any size wood to fire it.
See why I love my Cone Kiln? Here is a video clip and some pictures:
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