The Kon-Tiki biochar kiln is the fastest, cleanest way to make medium-sized batches of biochar from local biomass with minimal processing, and condition it for application.
The Kon-Tiki deep-cone flame-curtain process was developed by Dr Paul Taylor (author of 'The Biochar Revolution' book) and Hans-Peter Schmidt at the Ithaka Institute in Switzerland in 2014. In 2020 its use has been recorded in 80+ countries. The kiln was named Kon-Tiki after the Peruvian sun God, and inspired by the voyage of discovery of the Kon-Tiki raft Thor Heyerdahl sailed across the pacific.
According to Dr Paul Taylor, it takes 1 hour per inch or 20-25 minutes per cm to pyrolyse to the centre of a piece of wood. For eg., for a 10cm diameter it would take nearly 2 hours, so you have to stop adding the big wood at least 2 hours before finishing. An ideal top size might be 6-8cm diameter for the 1.2m Kon-Tiki biochar kiln. An electric log splitter to split up the big stuff makes for a better run, but there is flexibility and you can find what is efficient and clean for the wood and moisture content you have. Bigger, wetter or variable just takes more time, care and smoke.