Features of electric arc furnace

Electric arc furnaces use electric energy as their main energy source. Electric energy draws arcs through the discharge of graphite electrodes and the charge to generate a high temperature of 2000 ~ 6000 ℃ or more. The scrap steel raw materials are melted by arc radiation, temperature convection and heat conduction. During most of the time when the charge is melted, the high-temperature heat source is surrounded by the charge, and the heat loss caused by the high-temperature exhaust gas is relatively small, so the thermal efficiency is higher than that of other steelmaking equipment such as converters. In addition, the electric heating is easy to accurately control the furnace temperature, and the heating operation can be performed under any conditions such as oxidizing atmosphere or reducing atmosphere, normal pressure or vacuum according to process requirements.

The electric arc furnace steelmaking process is short, the equipment is simple, the operation is convenient, the pollution is relatively easy to control, the construction investment is small, the area is small, and it does not need to rely on the complex ironmaking system like the converter steelmaking.

Electric arc furnace steelmaking is highly adaptable to the charge. It uses scrap steel as the main raw material, but it can also use molten iron (blast furnace or hot metal furnace), sponge iron (DRI) or hot briquetting (HBI), pig iron and other solid And liquid iron-containing raw materials.

Because the atmosphere in the electric arc furnace steelmaking furnace is controllable, the slag adjustment or replacement operation is relatively easy, and the melting, decarburization, dephosphorization, degassing, and inclusion removal, temperature control, and composition can be completed in the same operating system Complex process operations at various stages such as adjustment (alloying). Electric arc furnace steelmaking can be produced intermittently, and production varieties can be flexibly exchanged within a certain range. In addition, modern electric arc furnaces can also use a large number of auxiliary energy sources, such as injecting heavy (light) oil, pulverized coal, and natural gas. Therefore, the electric arc furnace steelmaking process has strong adaptability, flexible operation and wide application.

Electric arc furnace can not only smelt high-quality steel with low phosphorus, sulfur, and oxygen content, but also can alloy with a variety of elements (including lead, boron, vanadium, titanium and rare earth elements that are easily oxidized) to produce various high-quality steels. Steel and alloy steel, such as ball bearing steel, stainless acid-resistant steel, tool steel, electrical steel, heat-resistant steel, magnetic materials, and special alloys.

Although electric arc furnace steelmaking has many advantages, due to the current cost of scrap steel and electricity prices in my country, electric arc furnace steelmaking cannot compete with converter steelmaking in general steel and long-term products. Electric arc furnace steelmaking only occupies a leading position in the production of special steels with small batches, multiple varieties and high alloy ratios.

At present, some short-process electric furnace manufacturers in the world generally use high-output electric arc furnaces. In addition, the traditional three-phase operation process with a reduction period has been gradually replaced by combined process technologies such as out-of-furnace refining, and the electric arc furnace and its public auxiliary facilities and equipment are more complete and reasonable. The proportion of electric furnace steel output in the world is increasing year by year.

my country is a developing country, the infrastructure construction has just started, the large-scale scrap steel recovery period has not yet arrived, and my country's power development is not balanced, and the current electricity price is still at a relatively high stage. Therefore, the development speed of electric arc furnace steelmaking in my country is limited, and there is no rapid development of converter steelmaking. Although the total amount of electric furnace steel is also increasing, the proportion of electric furnace steel output in total steel output has decreased year by year, which is contrary to the development trend of the world electric arc furnace.

With the development of my country's power facilities and the accumulation of scrap steel resources, as well as the country's strengthening of environmental protection and mineral resources management, the development trend of my country's electric arc furnace steelmaking will increase. By then, my country's electric arc furnace steelmaking technology will be more comprehensively developed.