Patent ID: 8444828

Claim:
A method for making char comprising the steps of: a. conveying carbon-bearing materials containing volatile material through a longitudinal pyrolyzer furnace housing, the longitudinal pyrolyzer furnace housing having at least two counter rotatable drive screws laterally positioned and overlapping within the longitudinal furnace housing, and each drive screw having a hollow drive shaft and a diverter longitudinally positioned within the drive shaft, the diverter forming with an inner surface of each drive shaft an inner passageway capable of directing heated fluid adjacent the carbon-bearing materials moving through the pyrolyzer furnace to fluidize the volatile material therein; b. burning fluidized volatile material and, if desired, other hydrocarbon fuels, in a combustion chamber adjacent the longitudinal pyrolyzer furnace housing, and exhausting combustion fluids through the inner passageway within the hollow drive shaft of the drive screws within the pyrolyzer furnace housing; and c. counter rotating the drive screws to cause carbon-bearing material containing volatile materials to move through the longitudinal pyrolyzer furnace housing and be heated to a temperature to fluidize volatile materials therein.