Special graphite is one of the irreplaceable and important resources in strategic emerging industries.
1. New carbon materials: special graphite
The main raw materials of special graphite are raw petroleum coke, raw pitch coke, medium-temperature asphalt and high-temperature asphalt. The production of special graphite is the deep processing and reuse of waste residues from the petrochemical and coal chemical industries.
The production of special graphite is characterized by complex processes and high technical requirements. Qualified special graphite generally needs to go through multiple processes such as calcination, grinding and kneading, pressing, roasting, impregnation, and graphitization. If there are higher requirements for product performance indicators, it will need to go through multiple processes such as impregnation and roasting, and the processes are interlocking.
Special graphite materials have the characteristics of high strength, high density, high purity, high chemical stability, high thermal and electrical conductivity, high temperature resistance, radiation resistance, strong lubricity and easy processing.
Special graphite materials can be divided into two types: medium-coarse structure graphite and fine-grain structure graphite in terms of material structure, which correspond to medium-coarse structure graphite and fine-structure graphite respectively. The forming method of medium-coarse structure graphite is mainly vibration molding, and the forming methods of fine-structured particle graphite are mainly molding molding and isostatic pressing.
2. Photovoltaic semiconductors lead new development momentum
Special graphite is an indispensable important material and industrial material for modern industry. Its terminal applications cover photovoltaics, semiconductors, new energy batteries, metallurgy, chemical industry, machinery, electronics and other intelligent manufacturing fields that are key developments in many countries.
• Photovoltaic industry
In the field of photovoltaics, special graphite is mainly used in graphite thermal field related components for single crystal silicon growth furnaces. Photovoltaic grade single crystal silicon growth furnaces are the core production equipment for photovoltaic grade single crystal silicon wafers. The rapid development of the photovoltaic solar energy industry directly drives the continued growth of the demand for special graphite industry.
• New energy battery industry
Special graphite is mainly used as a crucible for carbonization and sintering of negative electrode materials in the lithium battery industry. The negative electrode material is mainly used as the main body of lithium storage in lithium batteries. It realizes the insertion and deintercalation of lithium ions during the charging and discharging process. With the rapid development of the lithium battery industry, the demand for special graphite has increased significantly.
• Foundry industry
In the foundry industry, special graphite is an irreplaceable material for making crystallizers. It is used in the process of large-scale continuous casting to produce pure copper, bronze, and brass. It is a key component in the crystallizer.
• Rare earth industry
Special graphite is mainly used in graphite crucibles used in the sintering of permanent magnet materials in the rare earth industry.
• Nuclear industry
In high-temperature gas-cooled reactors, graphite is a neutron moderator and an excellent reflector. Its many excellent properties establish it as one of the key materials in the nuclear industry. In addition, special graphite can be used to make thermal structural parts, and isotropic graphite materials are used to make nuclear graphite products such as graphite balls, core materials, and electrodes.