With the development of steel-making industry, electric furnace smelting has changed from ordinary power electric furnace steel-making to high power, and then developed into ultra-high
Power (UHP) electric furnace steelmaking. It is reported that the ultra-high power electric furnace can save more than 22% electricity and smelting time per ton of steel
It can be shortened by 50% and the yield can be increased by 1.5 times N1. At present, this method has become the main method of electric furnace steelmaking in the world. from
The electric furnace used for ultra-high power steelmaking has large capacity and harsh smelting conditions, so ultra-high power (UHP) graphite electricity must be used
Electrode, UHP graphite electrode should have: the resistance should be as low as possible, about 5 "- 6 PQM or less, and electricity is allowed in use
The current density is more than 30A / cm2, and it should have the function of "stabilizing arc" and withstand thermal pressure and thermal shock in arc impact; high quality
The UHP graphite electrode will not crack or break under the thermal stress change caused by high current density; In addition, requirements:
The thermal expansion coefficient of graphite electrode is as low as possible and the mechanical strength is high
Soon, HP (high power) and UHP graphite electrodes were almost all used in large capacity electric furnaces. In recent years, electric furnace steelmaking has gradually
Develop toward large capacity and large specifications. And the proportion is increasing, but the domestic HP and UHP graphite electrodes are far from
To meet the needs, we can only rely on imports to solve the problem.
From the perspective of industrial development, UHP graphite electrodes are the inevitable trend of the development of the steel industry, while needle coke is used to produce HP
Needle coke is the main raw material of UHP graphite electrode. From the appearance, its structure has obvious flow lines. Particles after crushing
It is elongated like a needle, and the fiber structure can be observed under the microscope. It has obvious anisotropy, is easy to graphitize, and has a
Low coefficient of thermal expansion, resistivity, large bulk density and true density, and low content of metal impurities.
At present, needle coke used in China mainly depends on imports from tongben and the United States, which monopolizes China in terms of price and quality
If this problem is not solved, it will be difficult to establish China's own UHP graphite electrode industry N0 |
In order to adapt to the development of China's steel-making industry and realize the localization of UHP graphite electrode, domestic needle coke must be used. paper
The topic is based on the actual problems faced by China's carbon industry and our factory, through changing the binder and using additives
In this period, the research on producing UHP graphite electrode with domestic needle coke was carried out.