One of our group members has supplied the following report…
“After consulting with a few international experts and a few knowledgeable local people, we took their cautions seriously and decided to start with a small “open burn” rather than a trench burn which we originally intended. Recently we tried this for the first time on a small scale. The idea was to build a pyramid of wood (the base of ours was about 1 meter square) and light it from the top (rather than the bottom as in a more normal bonfire type burn.) This is called a pyrolysis pyramid, and it is the way charcoal has been made by Jack Daniels for a very long time (they filter their whiskey though charcoal.) As well as lighting from the top there is a need to hose the pile with water in places that it are burning too hot and forming ash rather than charcoal. The trial was successful in that we did end up with a nice pile of good quality charcoal. However to do this on a larger scale is daunting because of the amount of water that would be required to control the burn. Our next plan is to do an open trench burn (rather than covering the trench which is when the risk of explosions apparently increases.) Small cautious steps, and lots of learning along the way. (Photos below).
We’d like to come up with something simple that works on a large scale, and encourage foresters and horticulturists in our area to deal with their waste wood in this way and then enrich depleted soils with the biochar produced. …. a long term goal but one very worth pursuing, especially in light of the latest IPCC report. As you know, there is an urgency not just to cut global emissions, but to actually take carbon out of the atmosphere and lock it away safely for a very long time. Biochar is coming to be seen worldwide as one of the”solutions” to mitigate climate change.
I did watch the video Biochar – The Next Stage In Climate Action on your website and found it inspiring.
Comments on our project very welcome, cheers,
Katerina Seligman, on behalf of “The Renewables, Motueka” “