A char making apparatus comprising: a a longitudinal pyrolyzer furnace housing for heating carbon bearing material containing volatile materials to a temperature to fluidize volatile materials therein; b. at least two counter rotatable drive screws laterally positioned and overlapping within the longitudinal furnace housing, and adapted to convey carbon-bearing materials containing volatile material through the pyrolyzer furnace housing, each drive screw having a hollow drive shaft, characterized in that each drive screw has a diverter which is longitudinally positioned within each drive shaft and centered within the drive shaft by a plurality of ribs extending radially from an outer surface thereof, such that the outer surface of the diverter forms with an inner surface of the driveshaft an inner passageway to direct heated fluid adjacent the carbon-bearing materials moving through the pyrolyzer furnace to fluidize the volatile material therein and that the char making apparatus further comprises; c. a combustion chamber for burning the fluidized volatile material and, if desired, other hydrocarbon fuels, and having an exhaust in fluid communication with the inner passageway within the hollow drive shaft of the rotatable drive screws within the pyrolyzer furnace housing; d. a conduit between the pyrolyzer furnace housing and combustion chamber transferring the fluidized volatile material from the pyrolyzer furnace to the combustion chamber to be burned, e. double outer walls within the furnace housing at least partially around the drive screws and forming an outer passageway between the outer walls capable of conveying a flow of heated fluid adjacent the carbon-bearing materials moving through the pyrolyzer furnace housing to fluidize the volatile materials therein, and f. devices positioned in the outer passageway between the double outer walls adapted to cause the flow of heated fluid through said passageway to have a Reynolds number greater than 4000. a a longitudinal pyrolyzer furnace housing for heating carbon bearing material containing volatile materials to a temperature to fluidize volatile materials therein; b. at least two counter rotatable drive screws laterally positioned and overlapping within the longitudinal furnace housing, and adapted to convey carbon-bearing materials containing volatile material through the pyrolyzer furnace housing, each drive screw having a hollow drive shaft, characterized in that each drive screw has a diverter which is longitudinally positioned within each drive shaft and centered within the drive shaft by a plurality of ribs extending radially from an outer surface thereof, such that the outer surface of the diverter forms with an inner surface of the driveshaft an inner passageway to direct heated fluid adjacent the carbon-bearing materials moving through the pyrolyzer furnace to fluidize the volatile material therein and that the char making apparatus further comprises; c. a combustion chamber for burning the fluidized volatile material and, if desired, other hydrocarbon fuels, and having an exhaust in fluid communication with the inner passageway within the hollow drive shaft of the rotatable drive screws within the pyrolyzer furnace housing; d. a conduit between the pyrolyzer furnace housing and combustion chamber transferring the fluidized volatile material from the pyrolyzer furnace to the combustion chamber to be burned, e. double outer walls within the furnace housing at least partially around the drive screws and forming an outer passageway between the outer walls capable of conveying a flow of heated fluid adjacent the carbon-bearing materials moving through the pyrolyzer furnace housing to fluidize the volatile materials therein, and f. devices positioned in the outer passageway between the double outer walls adapted to cause the flow of heated fluid through said passageway to have a Reynolds number greater than 4000.