Physical and chemical characteristics of high-magnesian siderites

In this article, special attention was paid to the possibility of using the siderite iron ore of the Bakal deposit of the Chelyabinsk region as a complex coolant-flux material for partial replacement of scrap metal and slag-forming material. The use of this material favorably affects the yield of the liquid intermediate and the increase in the stability of the lining of the steelmaking units. A quantitative assessment of the effect of siderite on the technological parameters of steel smelting in a converter under the conditions of the oxygen converter shop of the Magnitogorsk Iron and Steel Works was carried out. The calculation was based on the modernized mathematical model created in the Microsoft Excel environment, which was based on the system of balance equations, solved jointly by the iteration method. The cooling effects of various materials that were used for melting were calculated: 1 % of the magnesian flux-coolant from the mass of the metal charge (4 tons) reduces the metal temperature by 37 °C, while limestone by 28 °C, crude dolomite by 31 °C, ferruginous dolomite and scrap by 14 °C. According to the cooling effect, 1 ton of magnesian flux-cooler replaces 2.6 tons of metal scrap, or 1.3 tons of limestone. Thermophysical properties of a complex magnesia flux-cooler (siderite ore) were studied using the STA (Iupiter 449 F3) synchronous thermoanalytical instrument (Iupiter 449 F3) from its application in steel smelting. The sequence and temperatures of the beginning of decarbonization of the main mineral-forming components of the magnesian flux-cooler are specified (MnCO3 - 370 °C, FeCO3 - 410 °C, MgCO3 - 670 °C, CaCO3 - 970 °C).