Biochar in the Hawaiian Luau Pit

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's pit is a TFOD. No metal cone required. His method of gradually adding new wood over glowing coals is exactly the same method as the cone kiln and qualifies this method as a TFOD. One difference is, he quenches with dirt instead of with water. Here is the link to his description of the method, with pictures:

http://hawaiibiochar.com/biochar-burn-demonstration/

He has since moved on to better, even cleaner biochar production methods, but for those just getting started, you might want to consider the pit. I have no doubt that the method was inspired by the traditional Hawaiian cooking method - the Luau Pit.

Josiah - thank you for sharing!

Moxham Kiln from Charmaster Dolph Cooke is a Flame Cap Kiln

Charmaster Dolph Cooke, from the lush forests of Northern New South Wales, Australia, is a leader in the open source biochar tech movement. I love his latest kiln, inspired by his amazing mentor, Geoff Moxham. Geoff died tragically in a woods accident a few years ago, so let that be a reminder to us all to keep safety first in mind, especially when dealing with big, hot kilns like this one.

You can still glean some of Geoff's wisdom at his website, Bodger's Hovel.

Dolph calls this big tube a Moxham Kiln, so that is how it shall be known. The Moxham kiln inspired me to come up with the nomenclature, TFOD (Top Fed Open Draft) to cover all devices that use this open burning method: cone kilns, pyramid kilns, open pit kilns and the Moxham kiln. This new class of kilns is ultra simple and amazingly clean and smoke free if operated correctly.

Here is a nice video that Dolph made on the Moxham Kiln, where he gives some tips on how to operate it:

Giant Cone Kiln in Illinois

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: DSC_0120DSC_0111 DSC_0115 DSC_0123 DSC_0126

Idea for Making Wood Vinegar in a Cone Kiln

I found this on a website somewhere - but forgot to copy the url. It is from Poland, I think. This set up is for capturing condensates from pyrolized wood. The condensates range from wood vinegar (pyroligneous acid) to bio-oil - an acid kind of crude oil. There is a lot of information I will post soon about using wood vinegar in farming. Here is what looks like a pretty simple method of making it:

This would be easy to do in a bottomless cone kiln. Just dig a hole under the kiln and set your two containers in the bottom of the kiln. Make sure the retort extends up into the cone kiln so it gets plenty of heat. I will be trying this soon and I'll let you know how it works.

Backyard Biochar Featured in Acres Magazine

Author Daniel Blaustein-Rejto did a pretty nice job on an article on farm scale biochar for Acres magazine. It's in the October 2014 issue: "Playing With Fire - Creating, Using Biochar for Improved Soil." Many of the pictures in the article are from technologies featured on this website. So thanks everyone, for contributing your pictures and stories. More and more people are learning about these small scale, clean biochar technologies, and using them to improve their soils.