A method for adjusting the position and oxygen pressure of a converter single slag-retaining oxygen lance and a smelting method

Abstract

The present invention provides a method for adjusting the oxygen lance position and oxygen pressure of a converter with single slag retention, comprising: when the converter adopts a single slag retention process, the height of the oxygen lance position is calculated according to formula (I); the oxygen pressure is calculated according to formula (II); H 留渣枪位 =H 不留渣枪位 ‑Wwt%×(TFe)wt%×(1300~1400)(Ⅰ); P 留渣 =P0+Wwt%×(0.050~0.060)(Ⅱ). The present application also provides a smelting method. The adjustment method provided in the present application can accurately adjust the oxygen lance position and oxygen pressure according to the slag retention amount and the end point of the slag retention, thereby reducing the influence of the slag retention on the process blowing effect, avoiding a series of problems such as process splashing and high final slag foaming caused by improper selection of the oxygen supply system due to the instability of the slag retention amount, etc., thereby improving the process control stability and the end point hit rate, and effectively reducing the influence of the single slag retention process on the converter blowing effect.

Description

Technical Field

[0001] The present invention relates to the technical field of converter steelmaking in the iron and steel metallurgical industry, and in particular to a method for adjusting the position and oxygen pressure of a converter single slag retained slag oxygen lance and a smelting method. Background Art

[0002] In converter steelmaking, the oxygen lance position is the distance from the end of the oxygen lance nozzle to the metal surface in the molten pool. Throughout the steelmaking process, the oxygen lance position is directly related to slagging, decarburization, temperature rise, and the occurrence of splashing. Therefore, to ensure a smooth steelmaking process, the oxygen lance position must be controlled.

[0003] In recent years, with increasingly fierce competition in the steel industry, major steel mills have gradually implemented the slag retention process in converters to reduce production costs. This process reduces slag material consumption and enables low-slag smelting. However, in actual operation, the oxygen lance position should be appropriately adjusted during converter smelting to mitigate the impact of the slag retention process on converter blowing. However, when using the single-slag retention process, the lance position is difficult to adjust stably due to the varying slag retention amount and final slag composition. Using too high a position can result in poor slagging in the early stages, severe dry-out in the middle and late stages, and poor slag height control in the later stages.

[0004] Therefore, in order to reduce the impact of slag retention on blowing, it is of great significance to provide a method for controlling the position of the oxygen lance in a single slag retention process. Summary of the Invention

[0005] The technical problem solved by the present invention is to provide a method for adjusting the lance position and oxygen pressure of a converter single slag retention oxygen lance, which can reduce the influence of the single slag retention process on the converter blowing effect.

[0006] In view of this, the present application provides a method for adjusting the lance position and oxygen pressure of a single slag retention oxygen lance in a converter, comprising:

[0007] When the converter adopts the single slag retention process, the height of the oxygen lance is calculated according to formula (I);

[0008] The oxygen pressure is calculated according to formula (II);

[0009] H 留渣枪位 =H 不留渣枪位 -Wwt%×(TFe)wt%×(1300~1400) (Ⅰ);

[0010] P 留渣 =P0+Wwt%×(0.050~0.060) (II);

[0011] Wherein, Wwt% is the mass percentage of the slag; H 留渣枪位 and H 不留渣枪位 The unit is mm;

[0012] P0 is the oxygen pressure without slag; P 留渣 and P0 are in MPa.

[0013] Preferably, W is 50-100.

[0014] Preferably, the TFe is 10-25.

[0015] Preferably, the W is 60-70.

[0016] Preferably, the TFe is 15-20.

[0017] Preferably, the gun position H is not left at the early stage. 不留渣枪位 The gun position without slag is 1500-1600mm, and the gun position without slag is H 不留渣枪位 It is 1100~1200mm.

[0018] Preferably, the slag-free early stage P0 is 0.85-0.87 MPa, the slag-free process P0 is 0.88-0.89 MPa, and the slag-free end point P0 is 0.90-0.91 MPa.

[0019] Preferably, the formula (I) is: H 留渣枪位 =H 不留渣枪位 -Wwt%×(TFe)wt%×(1330~1370).

[0020] Preferably, the formula (II) is: P 留渣 =P0+Wwt%×(0.055~0.057).

[0021] The present application also provides a smelting method, including a converter, wherein the oxygen lance position and oxygen pressure are adjusted in the converter process, and the method for adjusting the oxygen lance position and oxygen pressure is the same as the adjustment method described above.

[0022] The present application provides a method for adjusting the lance position and oxygen pressure of a single-slag slag retention oxygen lance in a converter, comprising: when the converter adopts a single-slag slag retention process, the height of the oxygen lance position is calculated according to formula (I); the oxygen pressure is calculated according to formula (II); the adjustment method provided in the present application can accurately adjust the lance position and oxygen pressure according to the slag retention amount and the end point of the slag retention, thereby reducing the influence of the slag retention on the process blowing effect, avoiding a series of problems such as process splashing and high final slag foaming caused by improper selection of the oxygen supply system due to instability of the slag retention amount, etc., improving the process control stability and the end point hit rate, and effectively reducing the influence of the single-slag slag retention process on the converter blowing effect. DETAILED DESCRIPTION

[0023] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0024] In view of the influence of the oxygen lance position and oxygen pressure on the converter blowing, the present application provides a method for adjusting the oxygen lance position and oxygen pressure of the converter single slag slag retention. By adjusting the oxygen lance position and oxygen pressure, the method reduces the influence of slag retention on the process blowing effect, avoids a series of problems such as process splashing and severe final slag foaming caused by improper selection of oxygen supply system due to instability of slag retention amount, etc., improves process control stability and endpoint hit rate, and effectively reduces the influence of the single slag slag retention process on the converter blowing effect. Specifically, the embodiment of the present invention discloses a method for adjusting the oxygen lance position and oxygen pressure of the converter single slag slag retention, comprising:

[0025] When the converter adopts the single slag retention process, the height of the oxygen lance is calculated according to formula (I);

[0026] The oxygen pressure is calculated according to formula (II);

[0027] H 留渣枪位 =H 不留渣枪位 -Wwt%×(TFe)wt%×(1300~1400) (Ⅰ);

[0028] P 留渣 =P0+Wwt%×(0.050~0.060) (II);

[0029] Wherein, Wwt% is the mass percentage of the slag; H 留渣枪位 and H 不留渣枪位 The unit is mm;

[0030] P0 is the oxygen pressure without slag; P 留渣 and P0 are in MPa.

[0031] Single-slag retention in a converter primarily involves retaining the slag from the previous furnace after splashing, as part of the slag material for the current furnace. This promotes rapid slagging and reduces the consumption of lime and other slag materials. The method for adjusting the oxygen lance position and oxygen pressure provided in this application is primarily applicable to the single-slag retention process.

[0032] In the calculation formula for the height and oxygen pressure of the oxygen lance position, W is the percentage of slag retention, and its value range is 50-100%. Specifically, W is 60-70%. For example, W in this application is 50%, 60%, 65%, and 100%.

[0033] In the oxygen lance height calculation formula, the TFe value range is 10-25%, specifically, the TFe value range is 15-20%; for example, the TFe values ​​in this application are 12%, 13%, 15%, 19%, and 21%.

[0034] In this application, in the calculation formula of the oxygen lance position height, the lance position H in the early stage without slag 不留渣枪位 1800~2000mm, preferably, the slag-free early gun position H 不留渣枪位 1800mm; No slag process gun position H 不留渣枪位 The slag-free process gun position is 1550mm; the slag-free end gun position H 不留渣枪位 The slag-free end gun position H is 1100-1200 mm. 不留渣枪位 It is 1150mm.

[0035] In the present application, in the calculation formula of the oxygen lance position, the 1300-1400 can be specifically selected from 1330-1370; in the specific embodiment of the present application, the calculation formula of the oxygen lance position is specifically: H 留渣枪位 =H 不留渣枪位 -Wwt%×(TFe)wt%×1330; Based on the above-mentioned determination of the height of the slag-free lance position and the mass percentage of the slag retention amount, the oxygen lance position is calculated according to formula (I), thereby achieving accurate adjustment of the oxygen lance position.

[0036] In the oxygen pressure calculation formula, P0 is the slag-free oxygen pressure. In the early stage of slag-free, P0 is 0.85-0.87 MPa, specifically, P0 is 0.86 MPa, 0.86 MPa, or 0.87 MPa. During the slag-free process, P0 is 0.88-0.89 MPa, specifically, P0 is 0.88 MPa or 0.89 MPa. At the slag-free end point, P0 is 0.90-0.91 MPa, specifically, P0 is 0.90 MPa or 0.91 MPa.

[0037] In the present application, in the calculation formula of oxygen pressure, the 0.050-0.060 can be specifically selected from 0.053-0.057; in the specific embodiment of the present application, the calculation formula of oxygen pressure is specifically: P 留渣 =P0+Wwt%×0.057; W is the percentage of slag retention, and its value range is 50-100%. Specifically, W is 60-70%. For example, W in this application is 50%, 60%, 65%, and 100%. Based on the determination of W, P can be obtained according to the calculation formula of oxygen pressure. 留渣 , thereby achieving accurate regulation of oxygen pressure.

[0038] The above-mentioned method for adjusting the height and oxygen pressure of the oxygen lance position in this application is mainly aimed at low-alloy steel, such as Q355B.

[0039] Furthermore, the present application also provides a smelting method, which includes a converter, that is, in the present application, the smelting method is carried out according to the methods and steps well known to those skilled in the art. In the converter step, it is necessary to adjust the oxygen lance position and oxygen pressure, and the method for adjusting the oxygen lance position and oxygen pressure is according to the described adjustment method.

[0040] The method for adjusting the lance position and oxygen pressure of the oxygen lance in the single slag retention process provided by the present invention can accurately adjust the lance position and oxygen pressure according to the slag retention amount and the terminal condition of the retained slag, thereby reducing the influence of the slag retention on the process blowing effect, avoiding a series of problems such as process splashing and high final slag foaming caused by improper selection of the oxygen supply system due to instability of the slag retention amount, etc., improving the process control stability and the terminal hit rate, and effectively reducing the influence of the single slag retention process on the converter blowing effect.

[0041] In order to further understand the present invention, the method for adjusting the position and oxygen pressure of the converter single slag retention oxygen lance provided by the present invention is described in detail below in conjunction with the embodiments. The scope of protection of the present invention is not limited by the following embodiments.

[0042] The method for adjusting the oxygen lance position and oxygen pressure in the single slag retention process according to the present invention was implemented in 7 cases in a 120t converter. In the following examples, the steel grade smelted in the converter is Q355B.

[0043] When the converter adopts the single slag retention process, the slag retention gun position is calculated using the following relationship:

[0044] H 留渣枪位 =H 不留渣枪位 -Wwt%×(TFe)wt%×1330;

[0045] Where: Wwt% is the percentage of slag; H 留渣枪位 and H 不留渣枪位 The unit is mm;

[0046] Oxygen pressure is calculated using the following relationship:

[0047] P 留渣 =P0+Wwt%×0.057;

[0048] Where: P0 is the oxygen pressure without slag; P 留渣 and P0 are in MPa.

[0049] The percentage of slag retention (Wwt%) and the slag retention (TFe) wt% of the embodiment are shown in Table 1;

[0050] Table 1 The percentage of slag retention (Wwt%) and the slag retention (TFe) wt% in the examples

[0051] project Residue percentage (Wwt%) (TFe)wt% Example 1 100％ 15％ Example 2 50％ 19％ Example 3 65％ 21％ Example 4 60％ 15％ Example 5 50％ 12％ Example 6 65％ 13％ Example 7 60％ 15％

[0052] The gun positions used in the embodiment and the gun positions used without slag are calculated based on the above relationship on the basis of Table 1, and the comparison is shown in Table 2;

[0053] Table 2 Comparison of the gun positions used in the embodiment and the gun positions used without slag

[0054]

[0055]

[0056] The oxygen pressure used in the embodiment and the oxygen pressure used without slag were calculated based on the above relationship on the basis of Table 1, and the comparison is shown in Table 3;

[0057] Table 3 Comparison of oxygen pressure used in the embodiment and oxygen pressure used without slag

[0058]

[0059]

[0060] During the smelting process of the embodiment, there was no process splashing, the degree of terminal slag foaming (the angle of the furnace from the slag to the furnace mouth during tapping is described, the angle is >82°) was low, the process control was stable, the terminal control was normal, and the converter blowing effect was good. The specific results are shown in Table 4.

[0061] Table 4 Statistics of process and endpoint control in the examples

[0062] project Is there any splashing during the process? Whether to pull carbon at one time The angle of the furnace shaking from the slag to the furnace mouth during steel tapping / ° Example 1 none yes 85 Example 2 none yes 84.5 Example 3 none yes 85 Example 4 none yes 83.8 Example 5 none yes 84.6 Example 6 none yes 84.7 Example 7 none yes 84

[0063] The above embodiments are only intended to help understand the method and core concept of the present invention. It should be noted that, without departing from the principles of the present invention, a number of improvements and modifications may be made to the present invention by those skilled in the art, and such improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0064] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for adjusting the position and oxygen pressure of a converter single slag retention oxygen lance, comprising: When the converter adopts the single slag retention process, the height of the oxygen lance is calculated according to formula (I); The oxygen pressure is calculated according to formula (II); H 留渣枪位 =H 不留渣枪位 -Wwt%×(TFe)wt%×(1300~1400) (Ⅰ); P 留渣 =P0+Wwt%× (0.050~0.060) (Ⅱ); Wherein, Wwt% is the mass percentage of the slag; H 留渣枪位 and H 不留渣枪位 The unit is mm; P0 is the oxygen pressure without slag; P 留渣 and P0 are in MPa.

2. The adjustment method according to claim 1, characterized in that: The W is 50-100.

3. The adjustment method according to claim 1, characterized in that: The TFe is 10-25.

4. The adjustment method according to claim 1 or 2, characterized in that: The W is 60-70.

5. The adjustment method according to claim 1 or 3, characterized in that: The TFe is 15-20.

6. The adjustment method according to claim 1, characterized in that: No residue left in the early stage gun position H 不留渣枪位 The gun position without slag is 1500-1600mm, and the gun position without slag is H 不留渣枪位 It is 1100~1200mm.

7. The adjustment method according to claim 1, characterized in that: The P0 in the early stage of no slag is 0.85~0.87MPa, the P0 in the process of no slag is 0.88~0.89MPa, and the P0 at the end point of no slag is 0.90~0.91MPa.

8. The adjustment method according to claim 1, characterized in that: The formula (I) is: 留渣枪位 =H 不留渣枪位 -Wwt%×(TFe)wt%×(1330~1370).

9. The adjustment method according to claim 1, characterized in that: The formula (II) is: 留渣 =P0+Wwt%×(0.055~0.057).

10. A smelting method comprising a converter, characterized in that: The oxygen lance position and oxygen pressure are adjusted in the converter process, and the method for adjusting the oxygen lance position and oxygen pressure is the adjustment method according to any one of claims 1 to 9.

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