On Thursday 23 December 2010 00:08:26 Crispin Pemberton-Pigott wrote: > Dear Andrew > > "Generally particulates are formed in the secondary combustion area. > From a long term health point of view particulates remain the bigger > problem over straight thermal conversion efficiency." > > This is certainly an area of active interest. What I seen so far shows > very little in the way of particles when the combustion is limited to a > region of low excess air and high temperature. It is a very > reproducible effect. We can go from nearly zero ug to say 2 mg/m^3 just > by changing the amount of secondary air.
It would be interesting to see how this secondary air was contributing to the effect. What if the secondary air were preheated to >800C? > > This supports your view about the secondary combustion zone. Tami Bond > also talks about particle growth in this zone, Of course I attribute this view to discussions on [stoves] with Tami. I have no accurate means of measuring particulates. From these discussions, recent research on the morphing of aliphatic ( chainlike) molecules to phenol type ( carbon rings) compounds as pyrolysis temperature increase and talking with my brother about the relative incombustibility of graphite ( close but weakly linked sheets of carbon rings) I'm tending to the conclusion that the conditions that favour ring type reforming of carbon atoms must be avoided. AJH _______________________________________________ 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
