Heat treatment apparatus

A heat treatment apparatus comprising:

• a first screw conveyor;
• a second screw conveyor in parallel with the first screw conveyor;
• a first nozzle pipe which is disposed on a lateral side of the first screw conveyor and which ejects a high-temperature gas composed of superheated steam or a high-temperature combustion gas;
• and
• a second nozzle pipe which is disposed on a lateral side of the second screw conveyor and which ejects a high-temperature gas composed of superheated steam or a high-temperature combustion gas,
• wherein, in the case where a discharge side is viewed from an input side for a raw material to be treated, the first nozzle pipe is disposed on a left lateral side of the first screw conveyor in the case where the first screw conveyor rotates right, and the first nozzle pipe is disposed on a right lateral side of the first screw conveyor in the case where the first screw conveyor rotates left, and
• in the case where a discharge side is viewed from an input side for a raw material to be treated, the second nozzle pipe is disposed on the left lateral side of the second screw conveyor in the case where the second screw conveyor rotates right, and the second nozzle pipe is disposed on the right lateral side of the second screw conveyor in the case where the second screw conveyor rotates left.