[Terrapreta] Fw: "Flare off" the producer gas from charcoal kilns! ... or you are tilting at windmills ... it's the methane, dummy
Sean K. Barry
sean.barry at juno.com
Sun Jun 3 15:18:29 CDT 2007
----- Original Message -----
From: Duane Pendergast<mailto:still.thinking at computare.org>
To: 'Sean K. Barry'<mailto:sean.barry at juno.com>
Sent: Sunday, June 03, 2007 12:36 PM
Subject: RE: "Flare off" the producer gas from charcoal kilns! ... or you are tilting at windmills ... it's the methane, dummy
Sean,
I think you sent your response only to me. Kurt has you nervous about bandwidth and carrying quotes.
I suppose forest fires are quite drastic polluters too. I was thinking of particulates - smoke - as the other criteria in your list - and there is the methane potential too as well as others which might degrade to methane and CO in the atmosphere.
Sometimes I wish the EPA would go after campfires. We do a lot of traveling in a Class B motorhome and campsites can get quite polluted.
If this concept gets going on the scale needed to be a significant sink I'm sure regulations will follow very closely. I seem to recall even burning the stubble off fields has been banned in some jurisdictions. Bingo!
http://www.agri.state.id.us/Categories/Environment/CropResidueDisposal/indexsmoke.php<http://www.agri.state.id.us/Categories/Environment/CropResidueDisposal/indexsmoke.php>
I don't think such regulations would be insurmountable, but it's hard to imagine we will be allowed to, or would want to, ignore charcoal production as a pollution source.
Duane
-----Original Message-----
From: Sean K. Barry [mailto:sean.barry at juno.com]
Sent: June 3, 2007 9:36 AM
To: still.thinking at computare.org
Subject: "Flare off" the producer gas from charcoal kilns! ... or you are tilting at windmills ... it's the methane, dummy
Hi Duane and All,
As I see it, the only one of those six "criteria pollutants" mentioned in the article you referenced, that is going to be released from pyrolysis of biomass (not municipal solid waste) is carbon monoxide. It is not a green house gas and it can be "flared off" No, SOx, NOx, lead, or ozone (O3) comes off of pyrolyzed wood chips at any temperature. Some Poly-aromatic hydrocarbons (PAH) can though; these are suspended vaporous liquids, the wood vinegar or wood tars that keeps being mentioned; things like pyroligneous acid, acetic acid, methanol, and etc.
They are pollutants, but not smog forming and not GHG. They are not soot (carbon particles blown off biomass during partial or full combustion). The vapors condense and they can make a gooey mess with some nasty stuff in the stacks of the kiln and/or intake ports of engines and such (if you are trying to utilize the energetic gas content by running an engine). There are known carcinogens in these PAH liquids. But, the EPA has not shut down campfires yet and these release more of this than probably the worst charcoal kilns that produce any charcoal at all. I contend the issue with methane gas release (CH4) from pyrolysis of biomass is a more significant problem. It is a GHG and a very potent one.
Hey, Michael! You were wondering about the half-life of green house gases the other day? The http://en.wikipedia.org/wiki/Greenhouse_gas<http://en.wikipedia.org/wiki/Greenhouse_gas> page talks a lot about that, if you were still interested.
Gasifier designs and operating methods can be made to reduce tars and gas output to minimum levels.
I'm a firm adherent now to the contention that producer gas should be "flared" at least, if it's not used for conversion to another energy form (sensible heat or generated electric power).
Regards,
SKB
-------------- next part --------------
An HTML attachment was scrubbed...
URL: /pipermail/terrapreta_bioenergylists.org/attachments/20070603/d702ecce/attachment-0001.html
More information about the Terrapreta
mailing list