Method for blowing out blast furnace

Abstract

The invention relates to a method for blowing out a blast furnace. The method comprises the following steps of: continuously adding iron ore and a solid carbonaceous substance into a blast furnace before blown out so that the height from a stock level to the horizontal plane of an iron notch is 86-93 percent of total eight of the blast furnace; when the adding volume of mixed materials is 65-75 percent of the total volume in the blast furnace, stopping adding the mixed materials; then leading the height from the stock level to the horizontal plane of the iron notch to be 45-65 percent of the total eight of the blast furnace by an empty stock level, spraying water into the blast furnace and predamping down; then continuously spraying water into the blast furnace and blowing air the blast furnace so that the stock level is reduced; when at least one of the following three conditions is met, opening the iron notch for tapping and then opening a residual iron notch for discharging slag iron; (1) calculating that the stock level depth reaches the horizontal plane of an air opening by the air blowing amount; (2) generating a second peak value of CO2 content in a change curve of the CO2 content; and (3) turning the combustion flame of the air opening to be yellow green. By adopting the method for blowing out a blast furnace, the probability for reducing the stock level in the blast furnace below the horizontal plane of the air opening after blowing out is as high as more than 90 percent.

Description

technical field [0001] The invention relates to a method for shutting down a blast furnace. Background technique [0002] Existing blast furnaces can be, for example, such as figure 1 In the structure shown, the blast furnace includes hearth 1, tuyeres 2, iron ports 3, residual iron ports 4 and relief valve 5, residual iron ports 4 are below tuyere 2, iron ports 3 are located between tuyere 2 and residual iron ports 4 In between, the release valve 5 is arranged on the upper end of the blast furnace, and the number of the release valves can generally be 2-6. In the process of blast furnace ironmaking, the hearth 1 holds the charge, blows air into the blast furnace through the tuyere 2 or shuts off the charge in the blast furnace, and the refined molten iron flows out through the iron hole 3, and the release valve 5 is used for discharge The gas generated in the blast furnace is used to adjust the pressure in the blast furnace, and the residual iron port 4 is used to dischar...

AI Technical Summary

Problems solved by technology

[0006] Although the method of drawing water from the top of the empty material line to stop the furnace can reduce manpower and material resources, however, after the blast furnace is shut down by using the existing method of drawing water from the top of the empty material line to stop the furnace, the material line stays about 0.5 meters above and below the level of the tuyere , usually about 0.5 meters above the tuyere level, still need to pay a lot of manpower and material resources to carry out the griddle

[0007] In order to ensure that the material line in the blast furnace is lowered below the tuyere as much as possible after the blast furnace is shut down, those skilled in the art have tried to install a temporary probe that will not be damaged at high temperatures (such as above 2300 ° C) in the blast furnace. However, the Temporary probes are expensive to manufacture and do not last long

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