Do not try this at home ! If this process is not followed correctly, bad things can happen.
I’m planning to make five batches of Bio-Char this winter, and I’m a bit behind schedule, so this weekend I decided to get my first burn out of the way. The process is very easy, but a bit time consuming. In total, I spent about 3 hours watching the fire, and adjusting the fuel to keep the barrel a consistent hot. What else is there to do on a Sunday when the temp hovers below 20 F ?
I had a good pile of scrap left from helping Santa this year, and used the wood to get the fire started. When the Cooker is good and hot, and all of the Water Vapor exits through the holes in the lid, then flammable gases will start pushing their way out.
The jets of flame are pretty cool to watch, and seem to dance as if they are alive. The color of the flame changes a bit from beginning to end. In the beginning the flame appears somewhat colorful, but as the batch nears completion, it looses it’s color, and becomes a dull yellow/orange.
When the burn was complete, and the barrel had cooled, I opened up the top to have a look. Above is the end result of my three hours of work, one batch of Bio-Char. The devils advocate may be asking why I would burn so much wood and release so much carbon to sequester this small amount of Greenhouse Gases ? The simple answer is that the carbon would be released no matter what… If the wood was left to rot, it would release the carbon any way. The only way to take this carbon out of the cycle is to bury it as Bio-Char. The real payoff will come for the next thousand years; you see this carbon will keep the soil fertile and alive for centuries to come. How do I know this ? Bi0-Char or “Terra Preta” was produced over 1500 years ago in South America, with the soil still bearing a dark color, and very good crop yields.
So if your reading this post several hundred years from now, and you’ve got that field I used to call a garden, your welcome….