Characteristics of graphitization process for high-purity graphite electrodes

In the fields of technology and industry, high-purity graphite electrodes play an indispensable role. They are widely used as high-temperature conductive materials in high-temperature environments such as steelmaking, submerged arc furnaces, and resistance furnaces. However, many people may not be aware that the graphitization process is one of the core links in the production of high-purity graphite electrodes. This article will educate you on the characteristics of the graphitization process for high-purity graphite electrodes.

1、 High temperature graphitization

Graphitization is a crucial step in the production of high-purity graphite electrodes. This process needs to be carried out at extremely high temperatures, usually reaching above 2700 ℃. This high-temperature environment helps to transform non graphite carbon into graphite carbon with a three-dimensional ordered structure of graphite. Through high-temperature treatment, the purity of graphite products is improved, and their thermal, electrical conductivity, thermal shock resistance, and chemical stability are also improved.

2、 Purity of raw materials

The raw materials for producing high-purity graphite electrodes require strict control of their purity. The lower the impurity content in the raw materials, the higher the purity of the final product. Therefore, strict screening and control are required for the selection, storage, and use of raw materials. Usually, the impurity content of high-purity graphite electrodes is required to be less than 0.05%, or even lower.

3、 Ventilation purification technology

Ventilation purification is an important step in the process of graphitization. When the furnace temperature reaches a specific temperature, nitrogen gas will be introduced, followed by purification treatment with gases such as chlorine and fluorine according to process requirements. These gases can react with impurities in the raw materials, expelling them from graphite products and further improving the purity of the products.

4、 The application of low ash materials

To ensure the purity of graphite products, low ash materials need to be used as insulation and resistance materials in the graphitization process. The selection and use of these materials are of great significance for improving the purity and performance of graphite products. Usually, low ash materials such as petroleum coke are used as insulation materials, resistance materials, and furnace bottom materials.

5、 Furnace loading and power transmission control

The charging and power transmission control of the graphitization furnace are also important factors affecting the graphitization effect. When installing the furnace, it is necessary to make a reasonable combination based on the volatile content of the raw materials to avoid excessive concentration and escape of high volatile components during the power transmission process. At the same time, the design of the power transmission curve also needs to fully consider the emission of volatile matter, ensuring that volatile matter can be slowly discharged and fully burned. In addition, reasonable selection of auxiliary materials and ensuring the particle size composition of auxiliary materials are also key factors to ensure the smooth progress of the graphitization process.

In short, the graphitization process of high-purity graphite electrodes is a complex and delicate process. Through the synergistic effect of high-temperature graphitization, purity control of raw materials, ventilation purification technology, application of low ash materials, and furnace loading and power transmission control, a high-purity graphite electrode with excellent performance is ultimately produced. These electrodes exhibit excellent conductivity and stability in high-temperature environments, providing strong support for the development of related industries.