Converter single-slag melting method of high-silicon molten iron

Abstract

The invention relates to a converter single-slag melting method of high-silicon molten iron. The method comprises the following steps of (1) heat balance calculation before oxygen blowing: before theoxygen blowing, according to the molten iron waste steel conditions, target temperature and carbon content control requirements, determining the consumption of lime and caustic calcined dolomite; then, calculating the ore addition total quantity according to the furnace turn test temperature; (2) material addition control: adding the materials into the furnace in three batches; (3) oxygen gun position control performed in four steps. The method provided by the invention achieves the goals of realizing the single slag operation of the high-silicon molten iron, shortening the melting time, achieving the melting balance without spraying and sputtering, reducing the melting time, the metal yield and improving the coal gas recovery and terminal residual manganese.

Description

technical field

[0001] The invention relates to the technical field of converter steelmaking, in particular to a control method when the converter uses high-silicon molten iron (Si>0.6%) and adopts single slag smelting. Background technique

[0002] The main metal materials for converter smelting are molten iron and steel scrap. The Si content in molten iron is an important heating element in the converter smelting process. The increase of the Si content can increase the heat source of the converter and increase the scrap ratio. At the same time, after the silicon content increases, the amount of molten iron slag increases, which is beneficial to dephosphorization and desulfurization. However, excessive silicon content in molten iron (generally refers to the silicon content of molten iron > 0.6%) brings great unfavorable factors to the operation of the converter, mainly as follows:

[0003] 1) Oxidation of silicon produces a large amount of acidic SiO 2 , in order t...

Examples

Embodiment Construction

[0035] A converter single-slag smelting method for high-silicon molten iron according to the present invention, the high-silicon molten iron refers to molten iron with a silicon content > 0.6%, comprising the following steps:

[0036] 1) Heat balance calculation before oxygen blowing;

[0037] Before oxygen blowing, determine the amount of activated lime and light-burned dolomite according to the conditions of molten iron scrap, target temperature and carbon content control requirements, and then calculate the total amount of ore added according to the excess temperature of the furnace;

[0038] 2) Material addition control;

[0039] For the first batch of materials, the molten iron is poured into the converter to start blowing and ignited, then add 2 / 3 of the total amount of active lime, and add all the light-burned dolomite;

[0040] When the total amount of ore is less than 7 tons, the first batch of materials is added at one time when the blowing starts; Oxygen is added ...

technical field

[0001] The invention relates to the technical field of converter steelmaking, in particular to a control method when the converter uses high-silicon molten iron (Si>0.6%) and adopts single slag smelting. Background technique

[0002] The main metal materials for converter smelting are molten iron and steel scrap. The Si content in molten iron is an important heating element in the converter smelting process. The increase of the Si content can increase the heat source of the converter and increase the scrap ratio. At the same time, after the silicon content increases, the amount of molten iron slag increases, which is beneficial to dephosphorization and desulfurization. However, excessive silicon content in molten iron (generally refers to the silicon content of molten iron > 0.6%) brings great unfavorable factors to the operation of the converter, mainly as follows:

[0003] 1) Oxidation of silicon produces a large amount of acidic SiO 2 , in order t...

Examples

Embodiment Construction

[0035] A converter single-slag smelting method for high-silicon molten iron according to the present invention, the high-silicon molten iron refers to molten iron with a silicon content > 0.6%, comprising the following steps:

[0036] 1) Heat balance calculation before oxygen blowing;

[0037] Before oxygen blowing, determine the amount of activated lime and light-burned dolomite according to the conditions of molten iron scrap, target temperature and carbon content control requirements, and then calculate the total amount of ore added according to the excess temperature of the furnace;

[0038] 2) Material addition control;

[0039] For the first batch of materials, the molten iron is poured into the converter to start blowing and ignited, then add 2 / 3 of the total amount of active lime, and add all the light-burned dolomite;

[0040] When the total amount of ore is less than 7 tons, the first batch of materials is added at one time when the blowing starts; Oxygen is added ...