a steelmaking method

Abstract

The invention discloses a steel-making method comprising the steps: within 60 seconds from the beginning of converting, controlling the oxygen lance position of top-blowing oxygen to be 1.8-2.3 meters, and controlling the oxygen supply flow to be 18000-23000Nm<3> / h; from the sixtieth second to the ninetieth second of converting, controlling the oxygen lance position of top-blowing oxygen to be 1.5-1.8 meters, and controlling the oxygen supply flow to be 29000-32000Nm>3> / h; after converting for 90 seconds, controlling the oxygen lance position of top-blowing oxygen to be 1.5-2.6 meters, and controlling the oxygen supply flow to be 40000-45000Nm>3> / h; within 11 minutes from the beginning of converting, controlling the flow of bottom-blowing inert gas to be 30-50Nm<3> / h; from the eleventh second of converting to the end of tapping, controlling the flow of the bottom-blowing inert gas to be 50-80Nm<3> / h. According to the method disclosed by the invention, the top-blowing oxygen flow, the oxygen lance position and the bottom-blowing inert gas flow of each period in a converter smelting process are reasonably controlled so as to ensure that leakage and explosion of a dry-process dust removal system can be prevented in a semi-steel making process adopting top-bottom combined blowing, thus reducing the damages to dry-process dust removal system equipment.

Description

technical field [0001] The invention relates to a semi-steel smelting method, in particular to a method for preventing dust removal and explosion relief during the semi-steel smelting process of preventing top and bottom double blowing. Background technique [0002] Oxygen converter top-bottom combined blowing method was developed in the late 1970s. It has the advantages of both top-blown and bottom-blown methods, and the equipment is simple, so it is easier to transform the original top-blown converter into a top-bottom blowing method. Compound blowing converter. Therefore, the converter top-bottom composite blowing method has been widely used in countries all over the world. In addition, with the continuous development of science and technology, in semi-steel smelting, the top-bottom composite blowing method is gradually used for smelting. [0003] Generally, the dust removal system in the semi-steel smelting process is mainly divided into dry dust removal system and wet...

AI Technical Summary

Problems solved by technology

[0004] However, there is a problem of explosion venting in the steelmaking process of semi-steel converter steelmaking using dry dust removal, which mainly occurs in the early stage of blowing. The reason is that the carbon-oxygen reaction gradually increases the CO obtained from the reaction. At this time, There is also a large amount of unburned oxygen. When CO and oxygen enter the electrostatic precipitator together, and the CO concentration reaches 9% and the oxygen concentration reaches 6%, the electrostatic precipitator is prone to deflagration, resulting in dry dust removal system Venting

[0005] In addition, in the semi-steel smelting process, even if the oxygen flow rate is reduced in the early stage of blowing, the leakage problem of the dry dust removal system cannot be well avoided

This may be due to the poor ignition caused by the addition of scrap steel and auxiliary materials during blowing, which enriches oxygen, and after ignition, the carbon and oxygen react violently to produce more CO, which makes the dust entering the dry dust removal system The concentration of CO and unburned oxygen in the electrostatic precipitator is high, and it is easy to reach the limit of explosion venting, which leads to the occurrence of explosion venting, and then causes damage to the equipment of the dry dust removal system, and the leakage process reduces the blowing process. The recovery of gas indirectly increases the production cost of converter steelmaking