During the calcination process, a series of deep changes occur in the structure and elemental composition of various carbonaceous raw materials, thereby improving their physical and chemical properties. The calcination quality of petroleum coke has a significant impact on the quality of finished carbon materials and the technical indicators of each process, so ensuring the calcination quality of raw materials is an important prerequisite for ensuring the quality of the final product.

Purpose of calcination:

1) Eliminate volatile matter and moisture from raw materials. After calcination, the volatile content is less than 0.5%, and the moisture content is less than 0.3%.

The volatile content and moisture content of the calcined coke represent the degree of calcination, and if they fail to meet the requirements, secondary shrinkage will occur and cracks will form during calcination.

2) Improve the density and mechanical strength of raw materials. True density 2.00g/cm ³ above.

The true density of calcined coke affects the true density of the final product, with poor mechanical strength and low bulk density. The main impact on molding is molding difficulty, and the height of the green block cannot meet the requirements within the required time, affecting the operation of the aluminum electrolytic cell, mainly manifested as slag falling.

3) Improve the electrical conductivity of raw materials.

The coke specific resistance after calcination affects the resistivity of the final product.

4) Improve the chemical stability of raw materials. Improved oxidation resistance.