Carbon and oxygen concentration product
That is, under a certain temperature and pressure, the product of the mass percent concentration of carbon and oxygen in molten steel is a constant, independent of the concentrations of reactants and products. The formula for calculating the carbon and oxygen concentration product of molten steel at 1600 °C is: [%C]×[%O]=0.0016%-0.0028%. In order to reduce the oxygen content of molten steel, each steel mill pursues the best carbon and oxygen concentration product. Shougang Jingcheng 200t The carbon and oxygen concentration of the steel produced by the converter is 0.0020%, which realizes the lower oxygen content of the initial molten steel.
Slag alkalinity
The ratio of the sum of the concentrations of basic oxides to the sum of the concentrations of acidic oxides in the slag is called slag basicity. Divided into binary alkalinity and quaternary alkalinity, representing the formula: binary alkalinity CaO%/SiO2%, quaternary alkalinity (CaO%+MgO%)/(SiO2%+Al2O3%). The basicity of the slag in the primary smelting furnace (converter or electric furnace) is generally 2.5-3.5, and the basicity of the slag in the refining furnace (LF ladle refining furnace) is determined according to the characteristics of the steel. For example, bearing steel); some steel grades need to control low-alumina acid gray slag (such as steel cord); some steel types need to control ash slag to ensure a certain oxygen content in the molten steel (such as chip-free steel).
The number of molten pool temperature rise
The amount of temperature rise of the molten pool per unit time is related to the conditions of molten iron, the collocation of scrap steel, the process parameters of the oxygen lance and the process control. The number of liters of temperature, °C; Q—the heat released by the oxidation of 1㎏ element, kJ; m—the amount of the heated object (metal, slag, lining), ㎏; c—the specific heat capacity of the heated object (metal, slag, lining), kJ/ （㎏·℃）c metal=1.05 kJ/（㎏·℃）, c slag=1.235 kJ/（㎏·℃）, c furnace lining=1.235 kJ/（㎏·℃）
Steel consumption (Kg/t)
It is an important indicator to measure the production cost of converters. The consumption is related to steel grades, molten iron conditions, slag consumption (lime), iron-containing raw materials and process operations, and molten steel oxidation. At present, various steel mills are studying the best operation mode of converters. , in a unified way, increase the recovery of iron-containing raw materials, and the consumption of iron and steel materials has broken through the principle calculation. Taking HRB400E and HRB500E as examples, the converter iron and steel materials reach below 1040kg/t, or even lower, which lays a good foundation for steel mills to save costs. Formula: (hot metal + scrap steel + pig iron block) / qualified output of converter * 1000.
