[Terrapreta] Fwd: torrefied wood or charcoal?

[Tom Miles]

Gerritt,

Your questions are easily answered by doing a proximate, ultimate (including
total chlorine) and elemental ash analysis of the briquettes. The proximate
analysis would give you the fixed carbon (char), volatile carbon and ash.
The ultimate analysis will give you the elemental components plus sulfur and
chlorine. So far, with the heating value you haven't spent much money. The
ash elemental analysis is more expensive since the ash must be calcined to
burn out the carbon, then analyzed for its constituent elements. That's
where you might pickup elements associated with non-wood additives (i.e.,
from coal or oil).    

I would expect to see a slightly higher volatile content in the new
briquette than the old. But not by much. I doubt that they have
fundamentally changed their process because the reported and tested
differences are so small. I think it's just a marketing play.    

That's a more sensible approach than endless speculation. Is the answer
worth $400 as sample to you?

The answer to the question about the ash is to get out the barbecue and make
the ash and try it. I would nto expect to see any difference between ashes.
Can you assume that they have changed their production in all their plants?
How much variation is there likely to be between Oregon, Missouri and
Mississippi?

In my recent exchanges with Kingsford they have indicated that there
currently is no excess char from their plants. If I was in their position
with such as good market I would look for ways to increase production with
no change in capital equipment. One solution would be to make a higher
volatile char. That way you make more mass, because you are converting less
to gas, and ash becomes a smaller part of the product. It contains higher
volatile so it will light a little faster. It might not last quite as long
as char because you started with less char in the product.   

Ash from charcoal briquettes is pretty a expensive soil amendment. ($1/lb
char, 20% ash = $5/lb ash) I hope it works for you.      

Tom


-----Original Message-----
From: terrapreta-bounces at bioenergylists.org
[mailto:terrapreta-bounces at bioenergylists.org] On Behalf Of Gerald Van
Koeverden
Sent: Sunday, March 02, 2008 5:35 AM
To: Kevin Chisholm
Cc: Terra Preta
Subject: Re: [Terrapreta] Fwd: torrefied wood or charcoal?

They already had accelerants in the original.  Why would they add  
even more? Why wouldn't they want to reproduce a typical slow-burning  
fire, like that of pure charcoal?

It is probably the combustion products of those added accelerants  
which have given charcoal briquette ash such a bad name for use as a  
soil amendment, because typically ash is a good fertilizer.  Every  
second recipe for making compost specifically recommends the  
avoidance of using charcoal briquette ash.

Which leaves us with a new question:  how would the ashes from  
Kingsford's new charcoal behave as a soil amendment?

gerald