Blast furnace top ignition method

Abstract

The invention relates to a blast furnace top ignition method. The method comprises the operation steps that (a) theoretical slag iron complete discharging time is calculated at the later stage of thelast slag iron discharging before damping down of a blast furnace; (b) a cloth bag glasses valve is closed after the damping down of the blast furnace, a backflow valve is opened after the damping down of the blast furnace, part of gas flow in the furnace is led out along a backflow pipe, and a furnace top ignition manhole is opened after backflow of the part of gas flow; (c) a coal gas kindling material is ignited and then put in an ignition port of an ignition gun, the ignition gun is turned on, and then the coal gas is ignited; and (d) furnace top steam and nitrogen are closed, the ignitiongun is turned on and extended into the furnace, the top of flame of the ignition gun is in contact with the material surface, the coal gas in the furnace automatically combusts when meeting the kindling material of the ignition gun, and the furnace top ignition operation is completed. By normalizing the furnace top ignition operation steps, the safety performance of the furnace top ignition operation of blast furnace operators can be improved, the time consumed by the furnace top ignition operation is shortened, and the danger caused by furnace top ignition in the abnormal damping down stateof the blast furnace is avoided.

Description

technical field [0001] The invention belongs to the technical field of blast furnace ironmaking, and relates to a blast furnace top ignition method. Background technique [0002] The blast furnace shutdown is a very important link in the blast furnace production. Generally, the shutdown time is more than 4 hours. According to the process requirements, the manhole at the top of the furnace is opened for ignition operation. The purpose is to burn the gas generated in the furnace in the shutdown state, so as to ensure the The maintenance work in the furnace top area is safe. [0003] At present, the top fire of the blast furnace shutdown furnace is basically to open the ignition manhole, ignite the ignition gun, start the ignition gun, allow the ignition gun to stretch into the top of the material surface in the furnace, and use the flame of the ignition gun as a kindling to ignite the gas in the furnace. [0004] There are many drawbacks and weak points in the existing method...

AI Technical Summary

Problems solved by technology

If the depth of the material line in the furnace is greater than 2.5 meters after the wind shutdown, it is difficult for the flame of the ignition gun to directly contact the gas in the furnace, and it is difficult to ignite and time-consuming; if the temperature of the furnace top is too low after the wind shutdown, the gas concentration in the furnace is low, The fire of the musket is difficult to ignite the gas in the furnace; if the furnace top equipment failure or the feeding system fails to feed the material and the wind is shut down, the material line after the wind break is more than 4 meters, and the danger of furnace top fire at this time is relatively high. It is easy to cause a large amount of gas combustion on the top of the furnace to reduce the volume and inhale air, causing explosion accidents

[0005] Under the existing technical conditions, there is no set of safe, effective and mature technical solutions for furnace top ignition. When blast furnace operators perform furnace top ignition, there are great safety risks and they often fail to ignite and affect the shutdown time of the blast furnace.