Here's the story of how I made this charcoal retort and the results.
I cut the bottom off the gas cylinder, attached a hinge and clamp. Then I welded on the burner pipe which I had made up from some sections of exhaust pipe that were lying around in the garage.
This is the burner pipe which was welded to the rest of the pipework.
This is the end that was welded into the cylinder.
And this is how it looked when it was finished. Next was to install it into an oil drum to contain the heat.
So, here it is in situ. Next thing is to go down to the woods and try it out.
We lit the fire in the drum and after about 40 minutes the wood gas starts coming through and burning.
Here, you can see the flames coming out of the holes in the burner pipe. It really roars and the cylinder actually gets red hot, generating even more gas.
Gets to be quite an inferno in there!
The results the first time I did it were a bit disappointing because I didn't let it get hot enough to get the gas really coming through. These photos are from the next attempt where it really got going and the result was 100% conversion of the wood to charcoal with no un-burnt wood at all.