Magnesium Carbon Ball

Magnesium carbon ball (also known as slag modifier) is a composite material composed of lightly burned magnesia and anthracite. Its chemical composition is MgO and C. Its main function is to adjust the converter slag.

The agent can reduce the superheat degree of the slag, increase the viscosity and fire resistance of the slag, and increase the MgO content of the slag from 3.0% to 4.5% to 8.0 to 12.0%, so as to meet the requirements of slag splashing furnace protection. Through the slag splashing of the converter, the erosion of the lining by the slag can be reduced, and the protection of the lining can be protected, thereby greatly increasing the converter age. At present, after the slag splashing furnace protection technology is adopted in China, the age of the converter has doubled.

The light magnesium oxide raw material used in the development of magnesium carbon spheres is calcined at 900 ～ 1000 ℃ using first-grade magnesite to form light-burned magnesium oxide with suitable activity and MgO ≥ 85%, so as to ensure that the MgO content of the product after mixing is 60%. The carbon material is mainly anthracite or coke, and its fixed carbon content should be high, which should generally be ≥75%. 

The burning degree of lightly burned magnesium oxide determines its activity. The lightly burned magnesium oxide with suitable activity has a fast hydration reaction in the mixing and drying process, a large amount of hydrated magnesium hydroxide is produced, and strong bonding ability. It can improve the spheronization rate and wet and dry strength of magnesium-carbon spheres, which is economical and can ensure the rapid use of slag. Therefore, light burned magnesium oxide with a reduction between 5% and 10% is selected. Lightly burned magnesia, anthracite or coke and admixtures are blended and finely ground in different proportions (fineness of 120 mesh, pass rate ≥ 95%), and the well-mixed mixture is vigorously stirred, and an appropriate amount is added while mixing The binder, the mixed material is formed on a high-pressure ball press, and the formed magnesium carbon ball is dried in a tunnel kiln at 150-250 ° C so that the moisture content is ≤1%.

Magnesium-carbon balls MgO C SiO2 65.5 9.8 4.2 18.6 2.5 The developed magnesium-carbon balls are ideal regulators for converters, which can improve the fire resistance and alkalinity of slag, and play a role in desulfurization and purification of molten steel. The magnesium oxide and carbon content of the magnesium carbon balls can be adjusted according to the size of the converter, the type of smelting steel, the operation method and the composition of the slag. The product has been applied to slag-spattering furnace converters in many domestic steel plants, and has achieved significant economic benefits.