Introduction: Make Your Own BioChar and Terra Preta

A simple way to make BioChar in a 55 gallon drum. Hoping to promote simple, scalable, environmentally sound methods for making biochar for improving the soil on small farms and in backyard gardens. And improving the air as well.

When you bury the carbon you are sequestering it out of the atmosphere for hundreds of years. A pound of carbon buried this way takes quite a bit of CO2 gas out of what's overhead.

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Step 1: Overview

Cartoon of the process. I would like to sketch some more designs and have people test them.

Step 2: Prep & Materials

55 Gallon Drum, with Lid
Drum sealing ring
Dry Biomass - usually wood & wood chips, or dung

Hoe, rake, shovel
Dust mask, ear protection, eye protection
Heavy gloves, boots
Hose & nozzle
Metal cutting circ saw or hammer & chisel

Step 3: Make the Charcoal

Seal up the lid and roll the drum onto the fire. You want the vent holes pointing down into the fire so that methane gases get flared off before they escape into the atmosphere, causing atmos damage.
The drum has to sit on the fire for several hours. First steam comes out for 2 to 4 hours, as the water boils off. Then, volatile gases (VOC's) such as methane and hydrogen start blazing out of the slots like blowtorches, for 1 to 2 hours. When the gases have all flared off, there will be little or no smoke. The carbon will start to burn, sucking oxygen into the barrel. That's when you want to stop the process by rolling the drum off the fire and covering the slots with sand to starve the oxygen. Water helps too, since you're happy with wet charcoal.

Step 4: Remove From Fire and Cool

Watch out for hot ground, hot sand!

Step 5: Making Biochar Into Terra Preta

Crush the charcoal with your grape smashers (boots). Add fungal wood chips, household compost, (especially milk, fish, and bones) leafy compost, chicken gickem, urine, grey water, worm tea, fish tank water, you name it! Try to get the charcoal juiced up with calcium, nitrogen, bacteria and fungus before you put it into your garden. Enjoy it for hundreds of years! The ancients added pottery shards, which may absorb toxins, but I like to use my hands in the soil, so I don't add that. Do add crushed clamshells and eggshells.

You just sequestered some carbon!

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Find out everything - International Biochar Initiative,
Hat Tip to Gunther Folke & his retort method:
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