Dingli petroleum coke dryer adopts advanced explosion-proof and flame-proof system design, adjustable feeding speed, simple operation, large production capacity and continuous operation. Due to the special structure of the rotating cylinder of the petroleum coke dryer, the materials in the cylinder and the outer cylinder will become more dispersed, and the contact with the air is more adequate, the heat exchange area is larger, and at the same time, because the heat is transferred outward layer by layer from the inner cylinder to the outer cylinder, so it also makes full use of the residual heat, reduces the heat loss, and improves the thermal efficiency by 30%-40%, and the heat transfer coefficient of the volume is twice as much as that of the single-cylinder dryer.