Use of graphite electrodes in steel making

Graphite electrode is the main market for electric arc furnace steelmaking, The steel industry uses graphite electrodes for about 80% of total consumption.

Use of graphite electrodes

Graphite electrode is mainly used to release electric energy in the form of arc to heat and melt the furnace burden. The graphite electrode is made of petroleum coke, and the needle coke is made of graphitization, because only graphite can withstand the high temperature in the arc furnace.
In EAF, the tip of the electrode can reach 3,000º Fahrenheit, which is half the temperature of the surface of sun. The graphite will sublime at 3550℃, so the Electric arc furnace electrodes is easier to bear At the same time, it can achieve smaller electrode loss.
Use of graphite electrodes in steel making

Electric arc furnace electrodes are mainly used in the Ac steelmaking arc furnace and Dc steelmaking arc furnace.

Properties of graphite used as electrodes

1) The high temperature resistance of graphite electrode can reach 3900°C, boiling point is 4250°C, and the working temperature of electric arc furnace is above 3000°C, so after high temperature arc burning, its loss is very small, graphite will increase with the temperature in the electric arc furnace The mechanical strength is strengthened. When the temperature reaches 2000°C, the strength of the graphite electrode is doubled.
2) The conductivity of the graphite electrode is 100 times higher than that of ordinary non-metallic minerals, because the average particle size of the graphite electrode is small, the discharge condition is stable, the better the surface quality, the greater the current. The graphite electrode has low loss, and the loss ratio with the copper electrode is 1:2. Strong thermal conductivity, graphite will become an insulator at extremely high temperatures.
3) The graphite electrode has stable chemical properties, and can resist acid, alkali and organic solvent corrosion at room temperature.
4) Easy to machine, the processing speed is 2~3 times faster than the copper electrode, and no additional manual processing is required.
5) Compared with copper electrode, light weight and low cost. The graphite electrode is directly sublimated and consumed during the steelmaking process, and no impurities will fall into the electric arc furnace.

Application of graphite electrodes

1) Main use of graphite electrodes are to make steel in arc furnace
The graphite electrode used in electric furnace steelmaking accounts for 70% ~ 80% of the total amount of graphite electrode. It USES the high-temperature heat source generated by the arc between the end of the electrode and the furnace burden to melt.
2) Used in ore thermal electric furnace
The ore thermal furnace is mainly used to produce industrial silicon and yellow phosphorus. The end of the electrode is buried in the furnace burden, an arc is formed in the furnace burden, and the heat energy from the furnace burden resistance is used to heat the furnace burden. Graphite electrode is needed for ore - thermic furnace with high current density. About 100kg of graphite electrode is consumed for every 1t of silicon produced, and about 40kg of graphite electrode is consumed for every 1t of yellow phosphorus produced.
3) For resistance furnace
The resistance furnace is a graphitization furnace for producing graphite products, a melting furnace for melting glass and an electric furnace for producing silicon carbide. The materials in the furnace are both heating resistances and heating objects. The graphite electrode is usually embedded in the furnace head wall at the end of the resistance furnace, where the graphite electrode is used for discontinuous consumption.
4) Used for processing special-shaped graphite products
The blank of graphite electrode is also used for processing various crucibles, moulds, dishes and heating bodies and other special-shaped graphite products. For example, in the quartz glass industry, graphite electrode blank 10t is required for every 1t of fused tube produced. For each 1t of quartz brick, 100kg of graphite electrode blank is consumed.