Petroleum coke is a combustible solid product obtained by coking petroleum residue and petroleum pitch. The color is black and porous, the main element is carbon, and the ash content is very low, generally below 0.5%. Petroleum coke belongs to the category of easily graphitized carbon. Petroleum coke has a wide range of uses in the chemical and metallurgical industries. It is the main raw material for the production of artificial graphite products and carbon products for electrolytic aluminum.
Petroleum coke can be divided into green coke and calcined coke according to the heat treatment temperature. The former is the petroleum coke obtained by delayed coking, which contains a large amount of volatile matter and has low mechanical strength. Calcined coke is obtained by calcining green coke. Most oil refineries in China only produce coke, and most of the calcination operations are carried out in carbon plants.
Petroleum coke is classified according to the level of sulfur content. It can be divided into three types: high-sulfur coke (sulfur content above 1.5%), medium-sulfur coke (sulfur content 0.5%-1.5%), and low-sulfur coke (sulfur content below 0.5%). Low-sulfur coke is generally used in the production of graphite electrodes and other artificial graphite products.