[Gasification] Lesson Learned

[gfwhell at aol.com]

A high temperature electric vacuum furnace can have an element formed from a solid rod of carbon.
The Rods we used were 9" in diameter, machined in such a way as to form a cylindrical element, the side walls slotted to form a zig zag path for the current. A crucible would stand in side the element which would have several thousand amps passing through it, The temperature obtainable being 1900 c or more.
My interest is: The role, a carbon grate would play in a gasifier?  I am not suggesting electricity be used to assist combustion . or the grate be used in the pyrolysis zone. It would be used in the CHAR zone in the absence of oxygen. much the same as the charcoal surrounding it,  and perhaps augment performance.
It would seem that at high temperatures, the oxygen content must be accurately controlled to safeguard the grate. A carbon grate in this area could be electrically connected to give a resistance reading to indicate temperature. It could also double as a means of igniting the biomass on start up.
A tubular grate, providing combustion air, and the gas extraction duct combined coaxially. with hot gas pre heating the air for combustion. 
 
GF
 
 
 
 
-----Original Message-----
From: bobstuart at sasktel.net
To: gasification at listserv.repp.org
Sent: Thu, 3 May 2007 12:48 AM
Subject: Re: [Gasification] Lesson Learned



On 2-May-07, at 7:39 PM, Jeff Davis wrote:

> Mark wrote:
>> Do you meat a carbon fiber composite? They are constructed with  
>> carbon
>> fibers in an epoxy substrate. The epoxy would be destroyed way early.
>
> Hi Mark,
>
> That's what I would think!

Race cars use carbon  fiber brake disks is a carbon matrix.  They  
work fine at and beyond red heat, but if the anti-oxidant coating  
gets nicked, the pit crew calls them "designer coal."  :-)


Best,
Bob Stuart




_______________________________________________
Gasification mailing list
Gasification at listserv.repp.org
http://listserv.repp.org/mailman/listinfo/gasification_listserv.repp.org
http://gasifiers.bioenergylists.org
________________________________________________________________________
AOL now offers free email to everyone.  Find out more about what's free from AOL at AOL.com.