[Stoves] Principles - draft from 2011

[Tom Miles]

Jock,

Thanks for the resurrecting the principles draft. These are helpful
observations about the products of pyrolysis and gasification but I think
you have provided a narrow definition of desirable biochar qualities.  

Your tests suggest discarding char that is hydrophobic (floaters), not
charred (brown bits), ashy (not neutral pH), smelly (creosote), or oily
(soap test). These are useful tests for characterizing the qualities of the
char but there is no reason to discard it because of these qualities. Just
use the chars appropriately. The floaters may serve to bulk a soil that may
be compacted. The incompletely charred material can also be used as an
amendment. It will eventually break down. Ashy char has more value as ash
than as char. I haven't seen a char yet with neutral pH. You may mean to say
that ashy char is likely to have a high pH and should be used appropriately.
>From what I have seen char that is oily or smells of creosote can be used to
growth abundant and healthy plants. 

Tom          

-----Original Message-----
From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of
Jock Gill
Sent: Saturday, April 06, 2013 8:27 AM
To: Discussion of biomass cooking stoves
Subject: [Stoves] Principles - draft from 2011

Perhaps these will be of interest to those working on "standards".  There is
far more to stoves than simple "performance" characteristics.  In the best
of all possible worlds, stoves are able to contribute much more than clean
stack gasses.  It would be desirable to look at the full spectrum of
potential benefits when evaluating stoves. In the developed economies at
least, the saying is that "benefits sell".  The implication is that features
are not as powerful a motivations for adoption.