Dear Crispin Dung washing in cold climates will be a very different matter than will be dung washing in the tropics, where there is warmth all year for sun drying moist dung, whether washed or unwashed. Also, the use of chimneys will certainly lessen health hazards.
The villain that makes the dioxins is chlorine present in the fuel. A very simple test for the presence of halogens (e.g., chlorine and fluorine) is to insert a piece of copper wire in the flame, to get it red hot. If halogens are present, the flame will turn green. This could be a helpful initial test, to determine if it is worth the high cost of testing for dioxins. Dioxins cannot exist, if chlorine is not present. Best wishes, Kevin ----- Original Message ----- From: Crispin Pemberton-Pigott To: 'Discussion of biomass cooking stoves' Sent: Tuesday, December 07, 2010 8:53 AM Subject: Re: [Stoves] Drawing down the dung pile Dear Kevin I am not repeating your many comments. They were all useful. Thanks. The places where dung will be used as fuel is where they are in use already. In other words it is not worth at this early stage planning on cleaning the fuel too much unless it assist combustion. We can work in stages: continued gathering of scattered data, working on anything that burns better, then tuning the fuel and the stove to produce a combination that is acceptable. What should happen is that the present system is evaluated for emissions as a baseline and the stove checked to make sure they 'cause no harm' beyond what is there now. Something we expect is that the flame temperature will be higher as the gases are burned more efficiently in lower excess air. If the chemistry suggests that dioxins will be higher (or high enough to be a concern for the local environment) then it needs to be quantified and limited. Regards Crispin ------------------------------------------------------------------------------ _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address Stoves mailing list 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/ [email protected] http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org ------------------------------------------------------------------------------ No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1170 / Virus Database: 426/3302 - Release Date: 12/07/10
_______________________________________________ Stoves mailing list to Send a Message to the list, use the email address Stoves mailing list 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/ [email protected] http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
