I've been watching Albert Bates' talks on youtube where he describes the Farm ecovillage and gives lots of details on the process of making biochar. What about making a rocket mass heater that produces biochar? I'm brainstorming and looking for input; if you make a rmh batch which means a side loading-- bigger firebox-- and had a big enough door/opening and a big enough firebox to accommodate a retort packed with wood I think you could send the initial gas from the retort through the rmh system and capture the heat and then be left with biochar.
I'm going to brainstorm some more on this concept but if anyone has more ideas that would be great. I think the mechanics and physics would work, maybe someone has done something like this already and we could learn from them.
Michael