Hey Everyone,
Or, getting to know “your” gasifier. I used my vac to remove the fuel layer by layer. Yes, it was tedious. I moved down about 1 1/2" or so at a time. I wanted to identify the pyrolysis zone and how far it was above the C/L of the nozzles. I did this by observing the condition of the fuel. When it changed from really dried looking to looking “roasted” with some charcoal spots, I had found it. I then continued removing fuel in layers down to the grate. The charcoal really takes off 2" to 3" above the C/L of the nozzles and continues to the grate. It is all very uniform in size and structure.
My hearth is gasketed and bolted to the flange on the bottom of the firetube. The top of my hourglass hearth (only 1/16" thick) has spots that reached the melting point as you can see. Good to see those temps in the oxidation zone. My next one will be at least 1/8" thick. It will also be located further under the nozzles to escape the blast area. The area between the hearth and the firetube wall is filled with sand. I’ll use a thicker material if I can find some way or someone to roll that thickness for me. I only found one clunker. It has a metallic sheen on the broken face. Next to the last pic.
The pictures may seem not to change much, so use the burn rings inside the firetube to gauge the amount removed. I start with an inside view of the layer, then I show the removed fuel in the bucket. Note the subtle color changes in the fuel. Note where the fuel starts to become partially charcoalized. You’re near the the border of the pyrolysis/oxidation zones. Everything look uniformly changed across the diameter? Good, you’ve got good nozzle penetration then. The oxidation zone is approx 2 1/2" above and below the C/L of the nozzles. The pyrolysis zone is from 2 1/2" above and 5" above the C/L of the nozzles. Above that is the drying zone. The reduction zone is evident, from restriction to grate. The last pic CW from upper left shows the totals of the various zones.
I am really satisfied with the performance from my “numbers”.
I thought you guys would like to see this part of my study.
Pepe
