Method for rapidly predicting thickness of furnace lining in converter smelting process

Abstract

The invention discloses a method for rapidly predicting the thickness of a furnace lining in the smelting process of a converter, and belongs to the technical field of ferrous metallurgy. The method is obtained through formula calculation according to the smelting furnace number and the molten steel end point oxygen content. When the end point oxygen content of the converter is larger than or equal to the end point oxygen content of the converter under the standard condition, the calculation formula is Hx = Hs-n * ln (O1-Os) O1-OS-1 (O1-OS) + k, when the converter end point oxygen content is lt; when the oxygen content at the end point of the converter is standard, the calculation formula is Hx = Hs-n * ln (Os-O1) O1-OS-1 (O1-OS) + k; hx in the formula is the thickness of the converter lining in the converter smelting process, mm; hs is the original thickness of the converter lining, mm; n is the number of smelting furnaces; o1 is converter end point oxygen content, ppm; os is the final oxygen content, ppm, of the converter under the standard condition; k is a correction coefficient. According to the invention, the thickness of the furnace lining at different parts in the converter smelting process can be measured on line.

Description

Technical Field

[0001] The invention belongs to the technical field of iron and steel metallurgy, and in particular relates to a method for quickly predicting the thickness of a lining in a converter smelting process. Background Art

[0002] The converter (BOF) lining is a crucial component of the converter steelmaking process, and its performance directly impacts steelmaking efficiency, production costs, equipment lifespan, and molten steel quality. BOF lining thickness is a key control parameter in the steelmaking process, and its optimal range requires precise management through thickness measurement technology, slag splash protection, and dynamic maintenance models. Optimizing lining thickness not only ensures safe production and process stability, but also reduces refractory costs and extends furnace life, making it key to improving the overall efficiency of steelmaking.

[0003] In modern steelmaking, timely and accurate measurement of lining thickness is crucial for ensuring converter steelmaking performance. However, converter lining measurement is a complex process, and the online measurement environment is harsh, requiring operators to withstand intense heat, posing a health risk. Rapidly assessing lining thickness changes while reducing the workload has long been a goal for industry practitioners.

[0004] Patent application number 202411046702.3 provides an online monitoring system and method for lining loss, establishing an online monitoring system through data analysis and sensor measurement. Patent application number CN202311821110.X provides a lining thickness measurement device and measurement and maintenance method, which improves measurement efficiency by optimizing traditional thickness measurement equipment. Both of the above existing technologies improve the equipment to achieve online measurement or monitoring of lining thickness, but neither solves the problem of long converter lining measurement time and harsh environment from the source. On the other hand, the innovation of equipment has increased steelmaking costs, affecting the overall efficiency of the steel plant. Therefore, on the whole, the above two methods are not the best options.

[0005] During the converter smelting process, the addition of raw materials, erosion of molten steel, and slag penetration all cause changes in the lining thickness. This change in lining thickness is directly related to the safe and stable production of steel and has a direct impact on molten steel quality. In actual operation, steelmakers typically visually observe changes in the lining between heats. When significant wear is detected, the converter is shut down and online measurements are performed using a laser thickness gauge to accurately determine the thickness variations in different parts of the converter. However, measuring the converter lining thickness requires multiple measurements at different locations throughout the converter to fully capture the lining thickness variations. This is not only time-consuming but also requires workers to endure high temperatures, posing a threat to their physical and mental health. Therefore, how to accurately predict converter lining thickness using smelting data, reduce lining measurement time, and reduce manual labor, remains a challenging technical challenge in steelmaking technology. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a method for quickly predicting the thickness of the lining during the converter smelting process, which can timely and effectively understand the changes in the thickness of the lining at different parts during the converter smelting process, and provide technical support for the maintenance of the converter lining and smooth production.

[0007] In order to solve the above technical problems, the technical solutions of the present invention are as follows: A method for quickly predicting the thickness of the lining during converter smelting is calculated using the following formula based on the number of smelting furnaces and the oxygen content of the molten steel at the end point; When the oxygen content at the converter end point is ≥ the oxygen content at the converter end point under standard conditions, the calculation formula for the lining thickness is: H x =H s -n*ln(O1-O s )|O1-O S | -1 (O1-O S )+k; When the oxygen content at the converter end point is less than the oxygen content at the converter end point under standard conditions, the calculation formula for the lining thickness is: H x =H s -n*ln(O s -O1)|O1-O S | -1 (O1-O S )+k; In the formula, Hx is the thickness of the lining during converter smelting, in mm; H s is the original thickness of the converter lining, in mm; n is the number of smelting furnaces; O1 is the oxygen content at the converter end point, in ppm; O sis the oxygen content of the converter at the end point under standard conditions, in ppm; k is the correction factor, which is 40mm when calculating the lining thickness of the furnace bottom and hearth, and 30mm when calculating the lining thickness of the furnace cap and furnace body.

[0008] Furthermore, the converter endpoint oxygen content under standard conditions described in the present invention refers to the oxygen content determined based on heat, oxygen and material balance calculations when the converter equipment and process parameters are all in ideal conditions, and the calculation method is a well-known technology in the art.

[0009] The beneficial effects of the technical solution of the present invention are: Compared with the conventional method of directly using laser radar to measure the thickness of the converter lining, which has the problems of long measurement time, great difficulty and low efficiency, the present invention takes a unique approach. By performing regression analysis on many factors affecting the lining and establishing optimal prediction parameters, it provides data that is closer to reality, laying the foundation for online monitoring of lining thickness in steelmaking and smooth steelmaking production.

[0010] This invention enables online measurement of converter lining thickness during the converter smelting process and can be applied on a large scale in steelmaking processes, offering simple operation and stable results. Compared to traditional steelmaking processes, this invention effectively reflects the changing patterns of converter linings, laying the foundation for lining maintenance, improving steelmaking control, and bringing significant social and economic benefits. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0012] In order to better illustrate the present invention, further examples are given below.

[0013] In each embodiment, the calculation formula of the lining thickness during the converter smelting process is as follows: When the oxygen content at the converter end point is ≥ the oxygen content at the converter end point under standard conditions, the calculation formula is: H x =H s -n*ln(O1-O s )|O1-O S | -1 (O1-O S )+k; When the oxygen content at the converter end point is less than the oxygen content at the converter end point under standard conditions, the calculation formula is: H x =H s -n*ln(O s -O1)|O1-O S |-1 (O1-O S )+k; In the formula, Hx is the thickness of the lining during converter smelting, in mm; H s is the original thickness of the converter lining, in mm; n is the number of smelting furnaces; O1 is the oxygen content at the converter end point, in ppm; O s is the oxygen content of the converter at the end point under standard conditions, in ppm; k is the correction factor, which is 40mm when calculating the lining thickness of the furnace bottom and hearth, and 30mm when calculating the lining thickness of the furnace cap and furnace body.

[0014] Example 1

[0015] This embodiment is a 120-ton converter, and the original thickness of the furnace lining is: the furnace cap cone section: 720 mm; the furnace body section: 830 mm; the hearth section: 1130 mm; and the furnace bottom thickness: 1000 mm.

[0016] The converter steelmaking production process was tracked, and the lining thickness at different locations was predicted under different working conditions. The lining thickness at different locations of the converter was measured using a thickness gauge to obtain the actual thickness. The results are shown in Table 1.

[0017] Table 1 Prediction results and actual measurement results of converter lining in Example 1

[0018] Example 2 This embodiment is a 100-ton converter, and the original thickness of the furnace lining is: furnace cap cone section: 750 mm; furnace body section: 850 mm; hearth section: 1200 mm; furnace bottom thickness: 1000 mm.

[0019] The converter steelmaking production process was tracked, and the lining thickness at different locations was predicted under different working conditions. The lining thickness at different locations of the converter was measured using a thickness gauge to obtain the actual thickness. The results are shown in Table 2.

[0020] Table 2 Prediction results and actual measurement results of converter lining in Example 2

[0021] Example 3 This embodiment is a 180-ton converter, and the original thickness of the furnace lining is: furnace cap cone section: 700 mm; furnace body section: 800 mm; hearth section: 1100 mm; furnace bottom thickness: 1000 mm.

[0022] The converter steelmaking production process was tracked, and the lining thickness at different locations was predicted under different working conditions. The lining thickness at different locations of the converter was measured using a thickness gauge to obtain the actual thickness. The results are shown in Table 3.

[0023] Table 3 Prediction results and actual measurement results of converter lining in Example 3

[0024] Example 4 The original thickness of the lining of the 260-ton converter is as follows: the cap cone section: 780 mm; the body section: 880 mm; the hearth section: 1150 mm; and the bottom section: 1000 mm.

[0025] The converter steelmaking production process was tracked, and the lining thickness at different locations was predicted under different working conditions. The lining thickness at different locations of the converter was measured using a thickness gauge to obtain the actual thickness. The results are shown in Table 4.

[0026] Table 4 Prediction results and actual measurement results of converter lining in Example 4

[0027] Example 5 This embodiment is a 120-ton converter, and the original thickness of the furnace lining is: the furnace cap cone section: 720 mm; the furnace body section: 830 mm; the hearth section: 1130 mm; and the furnace bottom thickness: 1000 mm.

[0028] The converter steelmaking production process was tracked, and the lining thickness at different locations was predicted under different working conditions. The lining thickness at different locations of the converter was measured using a thickness gauge to obtain the actual thickness. The results are shown in Table 5.

[0029] The steel types smelted in this embodiment and in Example 1 are different, and the reaction effects during the smelting process are different, resulting in different actual endpoint oxygen contents.

[0030] Table 5 Prediction results and actual measurement results of converter lining in Example 5

[0031] Example 6 This embodiment is a 100-ton converter, and the original thickness of the furnace lining is: furnace cap cone section: 750 mm; furnace body section: 850 mm; hearth section: 1200 mm; furnace bottom thickness: 1000 mm.

[0032] The converter steelmaking production process was tracked, and the lining thickness at different locations was predicted under different working conditions. The lining thickness at different locations of the converter was measured using a thickness gauge to obtain the actual thickness. The results are shown in Table 6.

[0033] The steel types smelted in this embodiment and in Example 2 are different, and the reaction effects during the smelting process are different, resulting in different actual endpoint oxygen contents.

[0034] Table 6 Prediction results and actual measurement results of converter lining in Example 6

[0035] Example 7 This embodiment is a 180-ton converter, and the original thickness of the furnace lining is: furnace cap cone section: 700 mm; furnace body section: 800 mm; hearth section: 1100 mm; furnace bottom thickness: 1000 mm.

[0036] The converter steelmaking production process was tracked, and the lining thickness at different locations was predicted under different working conditions. The lining thickness at different locations of the converter was measured using a thickness gauge to obtain the actual thickness. The results are shown in Table 7.

[0037] The steel types smelted in this embodiment and in Example 3 are different, and the reaction effects during the smelting process are different, resulting in different actual endpoint oxygen contents.

[0038] Table 7 Prediction results and actual measurement results of converter lining in Example 7

[0039] Example 8 This embodiment is a 260-ton converter, and the original thickness of the furnace lining is: furnace cap cone section: 780 mm; furnace body section: 880 mm; hearth section: 1150 mm; furnace bottom thickness: 1000 mm.

[0040] The converter steelmaking production process was tracked, and the lining thickness at different locations was predicted under different working conditions. The lining thickness at different locations of the converter was measured using a thickness gauge to obtain the actual thickness. The results are shown in Table 8.

[0041] The steel types smelted in this embodiment and in Example 4 are different, and the reaction effects during the smelting process are different, resulting in different actual endpoint oxygen contents.

[0042] Table 8 Prediction results and actual measurement results of converter lining in Example 8

[0043] As can be seen from Tables 1 to 8, in response to the changes in the converter lining, by monitoring smelting data such as the endpoint oxygen content, the lining thickness at different locations is predicted using the formula, and the error between the actual results is controlled within ±5mm, which is highly reliable and truly reflects the law of lining changes.

[0044] The above embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the present invention can still be modified or replaced by equivalents. Any modification or partial replacement that does not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A method for rapidly predicting the thickness of a lining in a converter smelting process, characterized in that: According to the number of smelting furnaces and the oxygen content of molten steel at the end point, it can be calculated by the following formula; When the oxygen content at the converter end point is ≥ the oxygen content at the converter end point under standard conditions, the calculation formula for the lining thickness is: H x =H s -n*ln(O1-O s )|O1-O S | -1 (O1-O S )+k; When the oxygen content at the converter end point is less than the oxygen content at the converter end point under standard conditions, the calculation formula for the lining thickness is: H x =H s -n*ln(O s -O1)|O1-O S | -1 (O1-O S )+k; In the formula, Hx is the thickness of the lining during converter smelting, in mm; H s is the original thickness of the converter lining, in mm; n is the number of smelting furnaces; O1 is the oxygen content at the converter end point, in ppm; O s is the oxygen content of the converter at the end point under standard conditions, in ppm; k is the correction factor, which is 40mm when calculating the lining thickness of the furnace bottom and hearth, and 30mm when calculating the lining thickness of the furnace cap and furnace body.

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