From the YouTube notes:
A 30 gallon retort heated by a 55 gallon TLUD is the basic idea. I've been a biochar enthusiast for 5 years now and riding the learning curve on how to make and use biochar at home. This device can run very cleanly. The cleanest I have seen for a simple batch device.
Playing with large, red hot, drums is a safety concern. So be thoughtful and careful if you try it. I am looking forward to making improvements to the design and looking forward to seeing anyone elses. This is an open architecture. If you come up with improvements, please share them.