Coal pyrolysis device

A coal pyrolysis device comprising:

• a rotary kiln type coal pyrolysis device main body that rotatably supports an inner cylinder inside an outer cylinder, the rotary kiln type coal pyrolysis device main body being configured to supply coal into the inner cylinder from a first end side of the inner cylinder as well as supplying heating gas into the outer cylinder and rotate the inner cylinder to heat and pyrolyze the coal while moving the coal from the first end side of the inner cylinder to a second end side and agitating the coal, and to output the pyrolyzed coal and pyrolyzed gas from the second end side of the inner cylinder;
• exhaust means provided connected to the outer cylinder, the exhaust means being for exhausting the heating gas within the outer cylinder;
• gas extraction means for extracting a portion of the heating gas exhausted by the exhaust gas means;
• and
• low-oxygen concentration gas supply means for supplying the heating gas extracted by the gas extraction means into the inner cylinder so that a concentration of oxygen contained in the heating gas is reduced.