REFRACTORIES FOR STEEL BASIC OXYGEN FURNACE
WE SUPPLY VARIOUS REFRACTORIES FOR STEEL BASIC OXYGEN FURNACE
Basic Oxygen Furnace (BOF) steelmaking operations are also sometimes referred to as Basic Oxygen Steelmaking (BOS). This is the most powerful and efficient steelmaking technology in the world. About 71% of crude steel is produced by this process. The BOF process was developed in the early 1950s at two steel plants in Linz and Donawitz, Austria, so the BOF process is also known as LD (the first letter of the two cities) steelmaking.
There are several variations on the BOF process. There are mainly top blowing, bottom blowing, and the combination of the two, which is the so-called joint blowing.
The steelmaking process is a spontaneous, or self-sufficient, energy source that uses gaseous oxygen (O2) to convert liquid iron (hot metal) into steel to oxidize unwanted impurities in the hot metal (HM). The oxygen used must be of high purity, usually a minimum of 99.5%, otherwise the steel may absorb harmful nitrogen (N2).
The main raw materials for steel plants are generally HM (about 80% or more) from the blast furnace and the remaining scrap. These are packed into BOF containers. Oxygen is blown into the BOF at supersonic speeds. It oxidizes the carbon (C) and silicon (Si) in the HM, releasing a lot of heat that melts the scrap. The oxidation of iron (Fe), manganese (Mn) and phosphorus (P) produces less energy. The flux used in this process is mainly calcined lime (more than 92% CaO). This lime is calcined from limestone low in silicon dioxide (SiO2). The combustion of carbon monoxide (CO) after leaving the converter also transfers heat back to the molten pool. The product of the steel plant is liquid steel with a specific chemical analysis at a temperature of about 1650 degrees Celsius.
The term "basic" refers to the furnace's refractory lining, made of alkaline materials (dolomite and magnesite). The refractory lining must have specific properties to withstand the corrosive effects of high temperature, highly oxidizing and basic slags, as well as wear during charging and blowing. Basic slag is required to remove P and sulfur(S) from the liquid charge.
In the steel industry, The refractory materials used in BOFs must withstand extreme temperatures, chemical erosion, and mechanical stress. Selecting the right refractory material is essential for ensuring the efficiency and longevity of the furnace. Here are some key considerations and recommendations for choosing the appropriate refractory materials for BOFs.
Recommended Refractory Materials
1. Magnesia Carbon Bricks:
These bricks are highly resistant to slag erosion and spalling, making them ideal for BOF linings. They offer excellent thermal shock resistance and maintain their structural integrity under rapid temperature changes.
2. High Alumina Bricks:
High alumina bricks provide superior strength and wear resistance, making them suitable for areas of the BOF that experience high mechanical stress. Their high melting point ensures they can withstand the extreme temperatures encountered in steelmaking.
3. Magnesia Chrome Bricks:
Magnesia chrome bricks offer excellent resistance to chemical attack and thermal shock. They are particularly useful in areas of the BOF where slag and chemical erosion are most severe.
Best Practices for Refractory Maintenance
1. Regular Inspection:
Conduct regular inspections of the refractory lining to identify any signs of wear, erosion, or damage. Early detection of issues can prevent minor problems from escalating into major repairs.
2. Proper Installation:
Ensure that refractory materials are installed correctly to maximize their performance. Proper fitting and alignment of bricks can reduce gaps and improve the overall integrity of the lining.
3. Temperature Control:
Implement advanced temperature control systems to manage the heating and cooling cycles of the furnace. Gradual temperature changes can reduce thermal stress and extend the service life of refractory materials.
4. Quality Control:
Source refractory materials from reputable suppliers who adhere to strict quality standards. High-purity raw materials and advanced manufacturing processes ensure superior performance and durability.
The related refractory materials products：
Magnesia brick
Magnesia ramming material
Magnesia cement
Gunning material