Method of increasing air quantity when blast furnace blows in without damping down

Abstract

The invention relates to a method of increasing air quantity when blast furnace blows in without damping down, characterized by that: using all tuyeres to supply air, adding fireproof sleeves on all tuyeres when the blast furnace blows in, taking off the sleeves gradually to increase the area of the tuyeres with the air quantity increases until all sleeves are taken off to keep the air speed and the kinetic energy at a required level, wherein, the sleeves are taken off without damping down. With small air quantity in the initial stage of blow-in, the air supplying with all tuyeres is realized, thus in the initial stage of blow-in the distributions of initial gas stream and temperature are reasonable, and the working condition of the hearth is uniform, active and stable. When the increasing of the air quantity is required, the increasing of the air quantity is realized by gradually poking the ceramic sleeves to increase the area of the tuyeres to keep the air speed and the kinetic energy at a resonable level, and the process of poking the ceramic sleeves is carried out without damping down, with being good for blast furnace blowing-in and reaching design capacity rapidly.

Description

technical field [0001] The invention relates to a method for continuous blasting and non-stop production when a blast furnace is turned on to increase the air volume, and belongs to the technical field of blast furnace smelting. Background technique [0002] Blast furnace smelting requires that under certain furnace capacity and certain raw material conditions, the wind speed and blast kinetic energy of the blast furnace must reach a certain value, otherwise it may cause the blast furnace condition to be unsatisfactory, and the production technical and economic indicators are poor. Therefore, the air supply system is a key factor affecting the initial gas flow distribution of the blast furnace, especially a reasonable air supply system at the initial stage of the blast furnace will promote the recovery of the furnace condition. The gas flow in front of the tuyere takes the roundabout as the radiation center, expands along both sides of the short radial direction and along t...

AI Technical Summary

Problems solved by technology

In order to completely block the tuyere, the refractory mud is usually very thick and hardened together with the tuyere. It is very difficult to open it. In this case, the wind must be turned off. This operation is not only laborious and time-consuming, but also affects the recovery of the furnace and affects production. Therefore, the blast furnace is most taboo to stop the wind

In addition, the way of partially blocking the tuyere will lead to unreasonable initial gas flow and temperature distribution of the blast furnace at the beginning of the blast furnace, and the problem of uneven working state of the hearth

[0004] With the improvement of raw materials and fuel conditions, the implementation of oxygen-enriched coal injection and technological progress, the utilization rate of blast furnace air has increased, the air consumption of pig iron smelting units has decreased, and the total air volume has decreased. In order to maintain a certain wind speed and blast kinetic energy, it must be reduced. The diameter of the small-diameter tuyere sleeves, and the small-diameter tuyere sleeves purchased before cannot be used. If all these large-diameter tuyere sleeves are scrapped, the loss will be great