What is the Power Source of Electric Arc Furnace?

The power source of the electric arc furnace is mainly electricity. Its core is to melt the metal through the high-temperature arc (up to 3000℃) generated between the electrode and the charge. The specific characteristics and classification of EAF, electric power, etc. will be discussed with you in this article.

Characteristics of Steelmaking Electric Arc Furnaces

1. Efficient smelting: The arc temperature is as high as 3000℃, which can quickly melt scrap steel, ferroalloys and other raw materials, and the smelting cycle is short (usually 40 ~ 60 minutes).

2. Flexible raw materials: mainly scrap steel, but also can be matched with direct reduced iron (DRI), pig iron, etc., with strong adaptability.

3. Energy saving & environmental protection: Compared with the blast furnace converter process, energy consumption is reduced by more than 50%, CO₂ emissions are reduced, and if it is matched with green electricity (such as wind power, photovoltaic), it is even lower carbon.

4. Precise temperature control: By adjusting the electrode current and voltage, the temperature in the furnace is accurately controlled, which is suitable for smelting special steel.

5. High degree of automation: Modern melting furnace use intelligent control systems to automatically adjust the electrode position, oxygen supply, etc.

Power Source of Electric Arc Furnace

1. Power input

The steelmaking electric arc furnaces directly relies on the external power system for power supply, usually requiring high voltage (such as 10kV or more) three-phase AC power, which is stepped down to hundreds of volts (such as 200400V) by a transformer and supplied to the graphite electrode.

The arc is triggered between the electrode and the metal material (such as scrap steel), and the electrical energy is converted into heat energy with an efficiency of more than 70%.

2. Auxiliary energy system

Burner: Some EAF are equipped with gas/oil burners for initial preheating of scrap steel (reducing arc energy consumption), but the main melting still relies on the arc.

Oxygen injection: Blowing oxygen to assist melting and oxidize impurities, shortening the smelting time, and indirectly reducing power consumption.

3. Energy ratio

In typical steelmaking electric arc furnaces , electrical energy accounts for about 6575% of the total energy consumption, and the rest is chemical energy (such as heat release from oxygen combustion) and recovered waste heat from exhaust gas.

4. Energy-saving technology

Scrap preheating: Using the exhaust gas from the melting furnace to preheat scrap (such as the Consteel process) can reduce power consumption by 2030kWh/t.

Frequency conversion control: Optimize electrode lifting and lowering adjustment to reduce reactive power loss.

It can be seen that the power energy of the electric arc furnace is mainly electricity, supplemented by a small amount of fossil fuels. Its high efficiency makes it the core equipment for short-process steelmaking (with scrap steel as the main raw material), which can reduce carbon emissions by more than 50% compared with the long process of blast furnace converter.

In recent years, EAF melting furnace have developed more towards green and intelligent development, such as with hydrogen burners, carbon capture technology, etc., to further reduce carbon emissions.

If you have any questions or needs about steelmaking electric furnaces and metallurgical equipment, please feel free to contact us for consultation and provide you with solutions.