[Stoves] [biochar-production] Re: Stoves Digest, Vol 14, Issue 17

[Frank Shields]

Good point!  Perhaps I need to rethink this. In woody materials the
carbonates will be formed as the cations are set free. But in char (as you
point out) they likely formed during the process using oxygen and carbon
from the wood. And perhaps the ash content (550 deg C with oxygen) is a true
ash reading. Thanks.

This is a great group.

Frank 



 
Frank Shields
Control Laboratories, Inc.
42 Hangar Way
Watsonville, CA  95076
(831) 724-5422 tel
(831) 724-3188 fax
frank at compostlab.com
www.compostlab.com
 
 
-----Original Message-----
From: stoves-bounces at lists.bioenergylists.org
[mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of
ajheggie at gmail.com
Sent: Thursday, October 27, 2011 1:06 AM
To: Discussion of biomass cooking stoves
Subject: Re: [Stoves] [biochar-production] Re: Stoves Digest, Vol 14,Issue
17

On Wednesday 26 October 2011 21:54:47 Frank Shields wrote:
> Because we 'make' more ash when we
> change the cations into carbonates (increasing weight) during the
> process. More cations from vegetative matter the more the problem. And
> this quantity of ash is not what we are spreading on the field. Also
> the carbon trapped in the ash (as CO3) is not included in the fixed
> carbon fraction - it should be because it comes from the organic carbon
> in the raw sample.

Just picking up on one small point in your post: I infer that you are 
saying as the sample is heated to  higher temperatures in the "ashing" 
process, to drive off remaining volatiles, carbonates form. In fact I 
suspect these are also a feature of chars from gasifiers.

I don't think this carbon can count as recalcitrant as it will be gassed 
off as CO2 in acid conditions.

AJH



_______________________________________________
Stoves mailing list

to Send a Message to the list, use the email address
stoves at lists.bioenergylists.org

to UNSUBSCRIBE or Change your List Settings use the web page
http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists
.org

for more Biomass Cooking Stoves,  News and Information see our web site:
http://www.bioenergylists.org/