[Terrapreta] Economics of biochar

[AJH]

On Tue, 8 Jan 2008 17:05:04 -0700, Greg and April wrote:

>Ok I admit it, I'm in over my head.

I'm sorry if that's my fault, the basic ideas a quite simple.

Charcoal is made by pyrolysis of wood, pyrolyse simple means to split
by heating. As you heat wood it splits into a char residue and an
offgas. The offgas composition varies with time and temperature and
inversely the remaining char varies in composition also, until
ultimately, at around 900C, the remaining char is quite pure carbon
but has reduced to about 15% of the weight of the original dry wood.

So theoretically we can tailor our charcoal yield by varying the
temperature but this doesn't happen in simple kilns.

I'll try to answer simple questions but I'm no teacher.

AJH