Method for rapidly adjusting smelting strength of blast furnace

Abstract

The invention provides a method for quickly adjusting the smelting strength of a blast furnace, which is characterized in that a tuyere neck bush is made of a refractory material, and the tuyere neck bush is a hollow tube with two open ends in the length direction; when the smelting strength of the blast furnace needs to be reduced, the tuyere neck bush is inserted into a tuyere small sleeve embedded in the blast furnace after damping down, so that hot air finally flows out of the tuyere neck bush and enters a hearth of the blast furnace, and the inner diameter of an air supply channel is reduced; when the smelting strength of the blast furnace needs to be recovered, a steel chisel is used for crushing the tuyere neck bush embedded in the tuyere small sleeve, then crushed materials obtained after crushing are pushed into a hearth of the blast furnace, and the inner diameter of the tuyere small sleeve is recovered to supply air into the hearth; when the smelting strength of the blast furnace is adjusted, the tuyere small sleeve does not need to be replaced, primary blast furnace damping-down is reduced, the damping-down time is shortened, the amount of heat compensation and net coke during re-blowing is reduced, the yield loss is reduced, the purchase cost of the tuyere small sleeve is reduced, and the damping-down time of the blast furnace is shortened.

Description

technical field [0001] The invention relates to the technical field of blast furnace ironmaking, in particular to a method for rapidly adjusting the smelting intensity of a blast furnace. Background technique [0002] After the cold air sent by the blower is heated to 800-1350°C by the hot blast stove, it enters the hearth continuously and stably through the tuyeres, and the hot air burns the coke in front of the tuyeres to produce hot reducing gas above 2000°C; the rising high-temperature gas flow heats The iron ore and the flux make them liquid, and make the iron ore complete a series of physical and chemical reactions, while the gas flow gradually cools down; there is intense heat transfer, mass transfer and transmission volume between the descending material column and the ascending gas flow. process. The blast furnace tuyere is on the iron-making blast furnace. The high-temperature hot air blown from the blast furnace tuyere and the coke at the bottom of the furnace ar...

AI Technical Summary

Problems solved by technology

[0003] Under the condition of a certain oxygen enrichment rate, there is an optimal range for the smelting intensity and utilization coefficient of the blast furnace. If the smelting intensity and utilization coefficient are too high or too low, the blast furnace cannot run smoothly.

Currently limited by production capacity and carbon emissions, the blast furnace needs to frequently adjust the smelting intensity and utilization factor. At present, after the oxygen enrichment rate is adjusted in place, the method of replacing small-area tuyere sets is often used to reduce the smelting intensity, but when the smelting intensity is restored, the tuyere needs to be replaced again. small set

According to 1350m 3 According to the calculation of the level of blast furnace, the blast furnace has a total of 24 tuyeres, 12 of which need to be adjusted in winter to limit production, and once the smelting intensity is reduced and restored, the wind needs to be shut down twice for 4 hours each time. The output of molten iron is 1,500 tons, and the direct economic loss is 1.5 million yuan