Blowing-out descending stockline control method for blast furnace

Abstract

The invention provides a blowing-out descending stockline control method for a blast furnace, which comprises the following steps: according to the time order, dividing the blowing-out process of a blast furnace into an ore reduction process, a coke excess process and an aerated oxygen excess process; measuring or calculating the real-time position of a stockline; and for the different positions of the stockline in different processes, adopting different blast volumes and different amounts of roof sprayed water in the blast furnace, and scheduling corresponding operations at appropriate tapping times to realize the blowing-out descending stockline operation of the blast furnace. The blowing-out descending stockline control method for a blast furnace can realize safe and fast blowing-out operation.

Description

technical field

[0001] The invention relates to the technical field of blast furnace production, and more specifically, relates to a control method for blast furnace shutdown and empty material line. Background technique

[0002] After a blast furnace has been in operation for a period of time, it needs to be shut down for overhaul or medium repair. During the blast furnace shutdown process, the operation and control of the empty material line is a relatively dangerous operation. If the operation is not done properly, it will lead to safety accidents. How to reasonably control the amount of air blast and the amount of water drawn from the top of the furnace at an appropriate time is the key to safely and quickly realizing the operation of the empty material line of the blast furnace shutdown. In the prior art, if the blowing process stops late, O 2 , part of the tuyeres are burnt out, resulting in excess oxygen, and some of them are not burnt out, and the tuyeres are still...

Examples

Embodiment 1

[0025] The new 3# blast furnace of a certain steel plant is shut down by using the blast furnace shut down empty material line control method according to the exemplary embodiment of the present invention. The capacity of the new 3# blast furnace is 2000m 3 .

[0026] According to the method of the present invention, the first demarcation point is located at the bosh position, and the volume of the bosh above the first demarcation point accounts for 55% to 65% of the total volume of the bosh. Here, the bosh volume above the first demarcation point is taken as Accounting for 55% of the total volume of the bosh, the calculation shows that the first dividing point is at the position where the depth of the material line is -22.4m. According to the method of the present invention, the second boundary point between the coke excess process and the air oxygen excess process is located at a position 0.5-0.8m above the tuyere, here, the second boundary point is located at a position 0....

Embodiment 2

[0030] The situation of this embodiment is basically the same as that of Example 1. This embodiment is based on the amount of oxygen blown into the blast furnace, the relationship between the amount of oxygen blown into the blast furnace and the consumption of coke in the charge, the volume relationship between the coke in the charge and the charge, and the initial value of the empty charge line. The real-time depth of the material line is calculated based on parameters such as the position of the material line and the type of the blast furnace.

[0031] Make statistics on the size of the blast furnace, the feeding situation of the empty material in the previous period before the shutdown of the furnace, and the physical and chemical properties of the raw materials (composition, stack specific gravity, etc.). In this embodiment, in the process of reducing ore, the K value representing the relationship between the amount of oxygen blasted into the blast furnace and the consumpti...

Embodiment 3

[0036] The situation of this embodiment is basically the same as that of Embodiment 1. In this embodiment, the following auxiliary methods are used to determine the position of the material line: in the early stage of the empty material line, the depth of the material line fed back by lengthening the probe is used; Changes in gas composition, coke blowing from the top of the furnace, and slag hanging from the tuyere to determine the approximate location.

[0037] Here, the real-time material line depth value measured with the extended probe in Example 3 is compared with the real-time material line depth value calculated in Example 2, and the results are shown in Table 2.

[0038] Table 2 embodiment 2 and embodiment 3 real-time material line depth value contrast

[0039]

[0040] It can be seen from Table 2 that the difference between the real-time material line depths measured in Examples 2 and 3 fluctuates between ±0.5m, which meets the required error range. It can be see...

technical field

[0001] The invention relates to the technical field of blast furnace production, and more specifically, relates to a control method for blast furnace shutdown and empty material line. Background technique

[0002] After a blast furnace has been in operation for a period of time, it needs to be shut down for overhaul or medium repair. During the blast furnace shutdown process, the operation and control of the empty material line is a relatively dangerous operation. If the operation is not done properly, it will lead to safety accidents. How to reasonably control the amount of air blast and the amount of water drawn from the top of the furnace at an appropriate time is the key to safely and quickly realizing the operation of the empty material line of the blast furnace shutdown. In the prior art, if the blowing process stops late, O 2 , part of the tuyeres are burnt out, resulting in excess oxygen, and some of them are not burnt out, and the tuyeres are still...

Examples

Embodiment 1

[0025] The new 3# blast furnace of a certain steel plant is shut down by using the blast furnace shut down empty material line control method according to the exemplary embodiment of the present invention. The capacity of the new 3# blast furnace is 2000m 3 .

[0026] According to the method of the present invention, the first demarcation point is located at the bosh position, and the volume of the bosh above the first demarcation point accounts for 55% to 65% of the total volume of the bosh. Here, the bosh volume above the first demarcation point is taken as Accounting for 55% of the total volume of the bosh, the calculation shows that the first dividing point is at the position where the depth of the material line is -22.4m. According to the method of the present invention, the second boundary point between the coke excess process and the air oxygen excess process is located at a position 0.5-0.8m above the tuyere, here, the second boundary point is located at a position 0....

Embodiment 2

[0030] The situation of this embodiment is basically the same as that of Example 1. This embodiment is based on the amount of oxygen blown into the blast furnace, the relationship between the amount of oxygen blown into the blast furnace and the consumption of coke in the charge, the volume relationship between the coke in the charge and the charge, and the initial value of the empty charge line. The real-time depth of the material line is calculated based on parameters such as the position of the material line and the type of the blast furnace.

[0031] Make statistics on the size of the blast furnace, the feeding situation of the empty material in the previous period before the shutdown of the furnace, and the physical and chemical properties of the raw materials (composition, stack specific gravity, etc.). In this embodiment, in the process of reducing ore, the K value representing the relationship between the amount of oxygen blasted into the blast furnace and the consumpti...

Embodiment 3

[0036] The situation of this embodiment is basically the same as that of Embodiment 1. In this embodiment, the following auxiliary methods are used to determine the position of the material line: in the early stage of the empty material line, the depth of the material line fed back by lengthening the probe is used; Changes in gas composition, coke blowing from the top of the furnace, and slag hanging from the tuyere to determine the approximate location.

[0037] Here, the real-time material line depth value measured with the extended probe in Example 3 is compared with the real-time material line depth value calculated in Example 2, and the results are shown in Table 2.

[0038] Table 2 embodiment 2 and embodiment 3 real-time material line depth value contrast

[0039]

[0040] It can be seen from Table 2 that the difference between the real-time material line depths measured in Examples 2 and 3 fluctuates between ±0.5m, which meets the required error range. It can be see...

Images