Needle coke and graphite electrode

The production process of carbon materials is a tightly controlled system engineering. The production of graphite electrodes, special carbon materials, aluminum carbon, new high-end carbon materials, etc. cannot be separated from the combination of raw materials, equipment, technology, management and related proprietary technology.

Raw materials are the key factors that determine the basic characteristics of carbon materials. The performance of raw materials determines the use performance of carbon materials. For the production of UHP and HP graphite electrodes, high-quality needle coke is the first choice, as well as high-quality binder asphalt and impregnant asphalt. But only high-quality raw materials, lack of equipment, technology, management elements and related proprietary technology, also can not produce high-quality UHP, HP graphite electrode.

Although the industrial production of needle coke in China is later than that of foreign enterprises, it has developed rapidly in recent years and has begun to take shape. In terms of the total production volume, it can basically meet the needs of domestic carbon enterprises for the production of UHP and HP graphite electrodes.

Foreign carbon enterprises often choose high-quality petroleum needle coke as the main raw material for producing large-scale UHP and HP graphite electrodes. Japanese carbon enterprises also use some coal-based needle coke as raw materials, but only for Φ Production of graphite electrodes with specifications below 600 mm. At present, China’s needle coke is mainly coal-based needle coke. Carbon enterprises often rely on imported petroleum needle coke for the production of high-quality and large-size UHP graphite electrodes. In particular, the production of high-quality joints uses imported Japanese Shuidao oil-based needle coke and British HSP oil-based needle coke as raw materials.

In terms of needle coke performance comparison, in addition to the conventional performance comparison, carbon enterprises should also pay attention to the characterization of needle coke, such as the classification of coefficient of thermal expansion (CTE), particle strength, anisotropy, expansion data in non suppressed state and suppressed state, and the temperature zone between expansion and contraction. Because these thermal properties of needle coke are very important to the control of graphitization process in the production of graphite electrode, of course, the influence of the thermal properties of asphalt coke formed after the baking of binder and impregnant asphalt cannot be excluded.

Only by mastering the characteristics of raw materials, selecting reasonable equipment matching, combining good process technology, and making the enterprise more scientific and reasonable in management, can we say that we have the foundation of producing high-quality ultra-high power and high-power graphite electrodes.

Post time: Jul-25-2022