[Stoves] Fw: : Re: Insulation and stove life
Rebecca A. Vermeer
ravermeer at telus.net
Fri Jun 14 22:17:27 CDT 2013
Hello JJ,
I see you are new at Stoves list. I am relatively new also—just joined the Stoves List after the January 2013 ETHOS CONFERENCE in Kirkland, Oregon. I have a stove project in the Philippines – see www.eco-kalan.com . Come to the STOVE CAMP 2013 at Aprovecho on July 22-25, 2013 in Cottage Grove, Oregon to learn about TLUD stoves (these use rice hulls) and rocket stove ovens –this will cost you $300 for the course. Hotel nearby has very reasonable weekly rate.
I am forwarding the recent discussions on the danger in using rice hulls for combustion due to cristobalite, just in case you have not seen these yet. More to follow. Welcome to the community.
Rebecca Arrieta (my Filipino maiden name) Vermeer
From: Rebecca A. Vermeer
Sent: Thursday, June 13, 2013 11:44 PM
To: Paul Olivier ; stoves at lists.bioenergylists.org
Cc: Rebecca A. Vermeer ; larry winiarski ; Jon Anderson
Subject: Fw: [Stoves] : Re: Insulation and stove life
Hello Paul,
Larry just told me that the silica content of rice hull ash is over 90%. At the ETHOS 2013 Conference, I saw a TURBO stove developed in the Philippines which used rice hull for fuel. Given your comment below regarding cristobalite “which is a nasty carcinogen” and severely hazardous to human health (see link below), would you recommend the use of rice hull as a household fuel for cookstoves?
Rebecca Vermeer
CRISTOBALITE LINK:
http://nj.gov/health/eoh/rtkweb/documents/fs/1657.pdf
From: Paul Olivier
Sent: Wednesday, June 12, 2013 12:01 AM
To: Discussion of biomass cooking stoves
Subject: Re: [Stoves] : Re: Insulation and stove life
Paal,
One thing I look for on my burner is that all burner holes support a flame throughout the process. If channeling occurs during the process or if char is being burned as the process comes to a close, then one can see burner holes that do not support a flame. This means that CO2 is being discharged from the burner holes, and of course CO2 does not burn. When CO2 is formed, this represents a big inefficiency, since combustion takes place far below the pot. When this happens the sides of the reactor can easily turn red hot and melt. I do not know how it is possible to spot the presence of CO2 if the top of the reactor stays open and does not have a lid with burner holes.
If one turns up the fan a bit too high resulting in channeling, it can happen that only a few holes (among a total of 80 in my case) do not support a flame. If I turn the fan down a bit and shake the reactor, this problem is immediately corrected. Also the effect of the presence of CO2 can be spotted by the cook in another way. The distribution of heat to the pan is not even.
Also many of the positive characteristics of biochar are lost when biochar is combusted and is reduced to ash. The combustion of biomass and biochar takes place when channeling occurs, and the combustion of biochar takes place if the fan is not turned off at the end of the process. Rice hull ash and rice hill biochar are not at all the same thing when it comes to growing plants. Also rice hull ash can easily contain cristobalite, which is a nasty carcinogen. Under ordinary conditions, no farmer should be handling this stuff.
Thanks.
Paul
On Wed, Jun 12, 2013 at 1:06 PM, Paal Wendelbo <paaw at online.no> wrote:
Ron
By end of flame the color of the char is red to yellow, that indicate a temperature of 700 to 800 ˚C and when there is no smoke, complete combustion has taken place. Is that not good for biochar?
Regards Paal W
_______________________________________________
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://stoves.bioenergylists.org/
--
Paul A. Olivier PhD
26/5 Phu Dong Thien Vuong
Dalat
Vietnam
Louisiana telephone: 1-337-447-4124 (rings Vietnam)
Mobile: 090-694-1573 (in Vietnam)
Skype address: Xpolivier
http://www.esrla.com/
--------------------------------------------------------------------------------
_______________________________________________
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://stoves.bioenergylists.org/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/attachments/20130614/2971c68e/attachment.html>
More information about the Stoves
mailing list