[ethos] RE: [Stoves] CO/CO2 Ratio in the Charcoal Stoves Tested at Aprovecho

[Dean Still]

Dear Tom,

I agree with several points that you make. I think that insulating around
and and raising temperatures above 725C in a cylinder above the fire has
been shown in our very preliminary experiments to potentially reduce CO when
burning charcoal. 

We have used Mexican charcoal in other experiments which seems to me to have
a lot more wood left in it so PM is a lot higher. I'll try the Mexican
charcoal as soon as possible.

I also agree that starting the stove with less charcoal might well help to
decrease the initial high levels of CO. 

I would like to put a damper in the stove to decrease draft in the start up
phase. Try to get above 725C as quickly as possible...

Nordica and Damon are hard at work to finish developing the Portable
Emissions Monitoring System that we hope will be widely available in January
for about $3,000. It seems to work as well as our more expensive hood here
at the Aprovecho lab. They developed the PEMS so that more folks could
monitor emissions and develop cleaner burning stoves.

We are planning our next book now that Comparing Cook Stoves and The World
Food Program book are finally at the printers. I agree again that a "State
of the Art" book covering lots of biomass topics seems like a fulfilling
next project.

Best,

Dean