Michael Cox wrote:One bonfire in the garden, quenched with water at the right moment, gets me about 100 litres of char and takes about 2 hours total.
The scale of production is just so unfavourable in an ordinary wood stove that it doesn't seem worthwhile in comparison. Plus I don't need to find tins to do it in!
Robert Alcock wrote:Is there a kind of biochar-making insert for a woodstove that you can actually buy? Or do you use some other material for the container?
Robert Alcock wrote:
Michael, I have also tried the bonfire method. I have found that the result is a mixture of all stages of charring (from uncharred wood to partially charred to ash) and is too coarse, so it would not be any good to add to the composting process, which is the next stage of using the biochar. I think you would need a very big bonfire to make 100 litres of usable char. Also you are producing a lot of smoke and CO2 and wasting the resulting heat. So it doesn't work for me, I'm afraid.
William Bronson wrote: For making it inside a woodstove how about an ammo can with the rubber gasket replaced with a suitable gasket?