Coking Pressure and Coke Shrinkage in Coke Oven

Abstract

Relationship between coking pressure, lateral shrinkage and vertical shrinkage during carbonization in coke oven was investigated by the use of movable-wall type test coke oven. The lateral shrinkage started to rise after the coking pressure disappeared. The final lateral shrinkage was 25 mm and slightly increased with increasing volatile matter content. The vertical shrinkage increased in proportion to the lateral shrinkage after the disappearance of coking pressure. The final vertical shrinkage decreased with increasing coking pressure and decreasing vertically applied force. The time when the vertical shrinkage starts to rise is considered to depend on the balance between the friction force between coke and oven wall caused by coking pressure and the vertical force applied on coke. The coke layer is pressed against the oven wall by high coking pressure and the coke cake is prevented from lowering which would result in wider fissures between coke lumps and thus harder pushing.