Steelmaking And Casting
The main objectives pursued in the ladle furnace in terms of refining the molten steel include the following:
- Alloy making;
- Homogenizing the molten material (in terms of temperature and chemical composition) using inert gases, e.g., argon or nitrogen; this process is called secondary metallurgy. Secondary metallurgy is based on quality and economic aspects;
- Desulfurization;
- Deoxygenation;
- Correcting or eliminating nonmetallic inclusions.
The ladle furnace is of the open type, the heating is created under atmospheric pressure, and the mixing of the molten material is done by the inert gas. Similar to the electric arc furnace, the arms holding the electrodes have been built based on low electrical resistance to create an electric arc with the molten material with minimized energy loss. The electrical energy consumption in the LF unit of the first phase of the steelmaking plant with a 30 MVA transformer and a maximum power of 22 MW is about 45 KWH/ton.
The LF unit plays an intermediary role between the melting and the continuous casting units in order to ensure sequential casting.
The raw materials used in this unit include:
- lime
- coke
- other slag makers such as bauxite and calcium aluminate
- ferroalloys (ferrosilicon, ferromanganese, ferrosilicon manganese, and so on)
- electrodes
- argon gas and CaSi and Al wires
which are consumed based on the manufacturing grade.