Circular seam gas control method for bottom spray gun of bottom oxygen blowing and bottom powder spraying converter

Abstract

The invention discloses a gas control method for a circular seam of a bottom spray gun of a bottom oxygen blowing and bottom powder spraying converter. Flow control or pressure control is adopted in the method. Flow control is adopted when the pressure of the circular seam ranges from 0.7 MPa to 1.7 MPa, and pressure control is adopted when the pressure of the circular seam is smaller than 0.7 MPa or larger than 1.7 MPa; the total circular seam flow of the natural gas of the bottom spray gun is 12-42 Nm < 3 > / min, and the set circular seam flow of a single branch pipe is 2-7 Nm < 3 > / min; according to the flow control process, (1.1) the pressure of the circular seam is increased along with the increase of the mushroom head, and when the pressure of the circular seam of any branch pipe reaches 1.1 KMa to 1.3 KMa, the flow of the circular seam of the branch pipe is reduced by 0.4 Nm < 3 > / min to 0.8 Nm < 3 > / min; (1.2) when the pressure of the circular seam of any branch pipe is larger than 1.3 KMa, the flow of the circular seam of the branch pipe is reduced by 0.8 Nm < 3 > / min to 1.2 Nm < 3 > / min; and (1.3) the pressure of the circular seam of the branch pipe in the step (1.1) or (1.2) is not reduced to 1.3 or below, and the flow of the circular seam of the branch pipe is maintained at the flow of the circular seam. According to the method, the service life of the bottom spray gun is prolonged, production accidents are avoided, and smooth production is guaranteed.

Description

technical field [0001] The invention belongs to the field of iron and steel smelting, in particular to a method for controlling the gas at the bottom lance of a bottom lance of a bottom-blowing oxygen-spraying bottom-spraying converter. Background technique [0002] Thanks to the stirring effect brought by the bottom blowing and the lime powder blown into the bottom spray gun can quickly form slag, the advantages of the bottom spraying oxygen top and bottom double blowing converter process are: high molten steel cleanliness, high metal yield, smelting cycle Short, smelting is not easy to splash and carbon and oxygen accumulation is small. However, during the production process, the bottom gun at the bottom of the furnace is in contact with high-temperature liquid molten steel, and oxygen is injected into the furnace through the central pipe to form an ignition zone above the bottom gun; the high temperature and oxygen environment at the top of the bottom gun nozzle can easil...

AI Technical Summary

Problems solved by technology

Generally, the increase of natural gas flow is conducive to the growth of the mushroom head, and the mushroom head is too large, which will lead to poor air permeability; the decrease of the natural gas flow rate will reduce the mushroom head, and the bottom gun is easy to burn.

If the bottom blowing gas is not properly controlled, it is easy to cause rapid damage to the bottom gun, shorten the life of the furnace bottom, and further damage the continuity and stability of production.