US Patent 7108767 Pyrolysis machine

Useful byproducts are recovered through the pyrolytic processing of biomass material such as vegetation, paper, or worn tires. The process is conducted in a sealed enclosure under vacuum or other controlled atmosphere. The biomass material is ablated and burned by crunching between counter-rotating rollers whose inner walls have been exposed to a highly heated fluid. The biomass material is preheated by injecting into the feeding duct super-heated: dry steam. A condenser within the enclosure reduces resulting vapors into oils that can be drained from the enclosure pan. Solid combustion residue is abstracted from the enclosure by an Archimedes screw.