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I wonder if putting water in the drum to quench the char that falls through might be a good idea to prevent finished char from going to ash.

Kelpie Wilson

That might be a good idea. On the other hand, it might not be needed at all if the seals are good. As long as the flame is active, that will keep air away from the char. Also, I don't know what would happen to the steam that is generated by dropping hot char into water. Hopefully Larry will send us another report.

John Wilson

Seams to me the lower Drum would be oxygen starved if not filled with co2 from the burn and should extinguish its self. Only one way to find out and that is to test the air inside for co2 or carbon monoxide.

John Wilson

Just took a second look at his rig and noticed that the lid is not sealed with a closing band. I'm sure you could not get a good seal with it to keep out oxygen as the lid will warp with the burn. When welding the cone to the lid be sure to have the sealing band in place and locked down or else the welding will warp and distort the lid. 30 years of being a boilermaker and welder makes this good advice to take.

Richard Roth

Here is an idea to try. Cut the hole for the char to fall through in the bottom of the barrel. Weld the cone and grating to the bottom of the barrel . Leave the lid off, just set the barrel with top down sealed in mud/earth. No way for air to get in. Lift the barrel off the pile of char when done. May want to weld a handle or two to the barrel.

Kelpie Wilson

Thanks John and Richard for your thoughts on sealing the drum. Both are good ideas. I might add that the rubber seals that come with the drum lid can be replaced with stove gasket so they don't burn up in the heat. I used stove gasket held in place with furnace cement quite successfully in a 55 gallon retort that I made. The lid never warped because it was clamped on pretty tight. The seal was good too.

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