This is what francois and I were discussing:
I was wondering if the charcoal cylinder had a taper so that it was asmaller at the bottom. It seems like some of the Brandt drawings show this. This might increase the upward velocity athe bottom and maybe lift burning charcoal up the cylinder. as the cylinder got wider the velocity would decrease so only the very fine charcoal would be carried with the gas!! Maybe if would not be necessary to fill the cylinder so often! If the air jacket cylinder were also tapered this may also help stop fuel bridging. because the fuel is falling into an ever increasing area.
The hoppers for the sawdust burning furnaces often had a sheet metal cone in the center to minimize bridging.
I am going to Central America for about 3 weeks to check on Rocket stoves
God Willing, I could try this on my old gasifier when I get back as it looked some what like a brandt but I did not have charcoal in the inner cylinder!!! It might have worked better had I done that as my reduction zone was too short.
----- Original Message -----
From: Francois PAL
Sent: Saturday, July 14, 2012 8:48 AM
Subject: re: [Drive On Wood!] brandt gasifier
The charcoal in the cylinder of the mid function was to make the gas purification,it may be consumed by the bottom, you have to be careful that there is no shortage,otherwise the gases are not purify, by this process that allows you to use of the softwood lumber and wood not dry,therefore it must be avoided to operate without the charcoal, well check, when filling the wood, the wood charcoal also.
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