Electric Arc Furnace VS Ladle Furnace

Electric arc furnace is often compared with ladle furnace. What is the difference between an electric arc furnace vs ladle furnace?

Electric Arc Furnace VS Ladle Furnace

An electric arc furnace is an electric furnace that uses the high temperature generated by the electrode arc to smelt ore and metal. When gas discharge forms an arc, the energy is very concentrated, and the temperature of the arc area is above 3000 ℃. For smelting metal, the electric arc furnace is more flexible than other steel-making furnaces. It can effectively remove sulfur, phosphorus and other impurities. The furnace temperature is easy to control, and the equipment covers a small area. It is suitable for smelting high-quality alloy steel.

With the improvement of electric arc furnace equipment and smelting technology, and the development of the electric power industry, the cost of electric arc furnace steelmaking continues to drop, electric arc furnace steelmaking is not only used to produce alloy steel, but also a large number of ordinary carbon steel. Its output proportion in the total output of steel in major industrial countries continues to rise.

The development of modern electric arc furnace smelting technology advances with the times. From the 1960s to the 1970s, the development of ultra-high power supply and related technologies was mainly focused on. The high-power arc furnace (HP) and ultra-high power arc furnace (UHP) were compared with the general ordinary power arc furnace (RP). They are mainly distinguished according to the capacity of transformer per ton of furnace capacity, which has a higher trend in recent years. This means that the heat energy input to the arc furnace in unit time is greatly increased and the melting time is significantly shortened, thus improving the production capacity, reducing the electrode consumption, reducing the heat loss, and reducing the electric energy consumption. As a result, the production capacity is further increased and the cost is also greatly reduced.

The high-pressure long arc operation, water-cooled furnace wall, water-cooled furnace cover, foam slag technology, and the use of external heat source for melting have been widely adopted, and the ladle refining and enhanced oxygen consumption have also been adopted. In the 1980s, the development of LF and EBT technologies made the modern electric arc furnace steelmaking process of electric arc furnace smelting and external refining basically mature. It is worth noting that since then, the focus of people’s attention has no longer been the use of DC or AC power supply, but the utilization of secondary combustion and flue gas sensible heat, that is, the preheating of scrap steel. Different types of modern electric arc furnaces have been produced in different ways of preheating scrap steel, including ordinary electric arc furnaces preheating scrap steel with a basket, flue shaft furnaces with supporting claws, double shell electric arc furnaces and Consteel electric arc furnaces. At present, the equipment and production technology of electric arc furnaces are still developing.

Electric Arc Furnace VS Ladle Furnace

A ladle furnace is an independent type of furnace. In addition to providing semi-finished liquid steel for the primary smelting furnace, other refining tasks and refining process arrangements can be completed independently. A ladle furnace is an external refining technology using arc heating under vacuum conditions. It is to put the molten steel initially melted in the general steel-making furnace into a special ladle for refining. This technology was developed by Japan Datong Steel Co., Ltd. in 1971 on the basis of studying asea-skf, refining furnace, VAD furnace, VOD method and other refining technologies and equipment, using the mature experience of other refining methods and avoiding its difficulties. A ladle furnace is important metallurgical equipment used to refine the molten steel melted in the primary smelting furnace (electric arc furnace, open hearth furnace and converter), and can adjust the temperature of molten steel, buffer the process and meet the requirements of continuous casting and continuous rolling. A ladle furnace is one of the main types of equipment for refining outside the furnace.

Main Functions of Ladle Furnace:

1. Make the molten steel temperature rise and keep warm. The molten steel is heated by an electric arc to obtain new heat energy, which can not only add alloy and adjust composition during ladle refining, but also add slag to facilitate deep desulfurization and deoxidation of molten steel. Moreover, the opening temperature of molten steel required by continuous casting can be guaranteed, which is beneficial to the improvement of the quality of dry cast slab.

2. Argon stirring function. Argon is blown into the molten steel through the permeable brick installed at the bottom of the ladle, and the molten steel has a certain stirring function.

3. Vacuum degassing function. After the ladle is hoisted into the vacuum tank, the steam jet pump is used for vacuum degassing, and argon is blown into the bottom of the ladle to stir the molten steel. The hydrogen content and nitrogen content in the molten steel can be removed, and the oxygen content and sulfur content can be further reduced. Finally, molten steel with high purity and excellent performance can be obtained.

For the whole enterprise, the application of a ladle furnace can at least increase the following benefits: speed up the production rhythm and improve the overall metallurgical production efficiency. Application: ladle furnace is widely used in industry, steel, metallurgy, and other industries.