Method for judging steelmaking splashing dry returning through combination of furnace gas and audio frequency

Abstract

The invention relates to the technical field of steelmaking production, in particular to a method for judging steelmaking splashing and drying by combining furnace gas and audio frequency, which comprises the following steps: continuously calculating the difference value between the current gas value 1 and the gas value before the set time to obtain the slope; continuously calculating the difference value between the current gas value 2 and the gas value before the set time so as to obtain the slope; the converter noise audio is divided into an audio dry-returning area, an audio splashing area, an audio normal area, a high-order audio value splashing area and a low-order audio value dry-returning area; and S5, splashing drying and trend determination. The method has the advantages that the real-time data of the array queue CO and the array queue CO2 are stored and analyzed, the splashing and drying conditions in the steelmaking process can be accurately judged, the judgment mode based on quantitative data overcomes the defect of inaccuracy of traditional judgment only based on artificial experience or a single audio system, and the judgment efficiency is improved. And the phenomena of splashing and drying caused by misjudgment are effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of steelmaking production, and in particular to a method for judging steelmaking splashing and drying by combining furnace gas and audio frequency. Background Art

[0002] During the steelmaking process, splashing and backdrying have a significant impact. Splashing can cause significant heat loss and iron loss in the molten iron slag, while also generating large amounts of smoke and dust, which pollutes the environment. Backdrying can also hinder the decarburization reaction, resulting in poor dephosphorization and, in turn, impacting steel quality. Traditional steelmaking operations rely primarily on manual judgment, relying on operators to visually observe the fire and determine splashing and backdrying based on experience. However, due to varying operator skills, quantitative analysis is difficult, and splashing and backdrying can sometimes be caused by misjudgment. Some steel mills use audio detection systems to detect splashing and backdrying. This system uses a microphone probe to detect specific frequency bands of sound within the molten pool during steelmaking blowing, and uses the sound intensity to determine splashing and backdrying. However, this method is not always accurate. For example, even when the oxygen lance tip is encapsulated by liquid steel and gas-liquid slag in good slag conditions, this can still be in the splashing zone, leading to misjudgment.

[0003] With the development of furnace gas systems, people have gradually come to understand that steelmaking is primarily a decarburization reaction, and that the carbon monoxide and carbon dioxide levels in the furnace gas can directly reflect the decarburization trend. Changes in the decarburization trend often indicate the occurrence of splashing or dryout in the molten pool. During splashing, the furnace gas is suddenly covered by slag and pushed upward, causing the furnace gas value to drop suddenly. Before dryout, the reaction between oxygen ions in the iron oxide and carbon in the molten iron accelerates, causing the furnace gas value to be stronger than usual, indicating a dryout trend. As the furnace gas value gradually decreases, while the oxygen blowing level remains constant, iron oxidation gradually increases, iron oxide accumulates in the slag, and the molten pool develops a slag-active trend. However, when dryout occurs, the low iron oxide content in the slag slows the decarburization reaction with carbon in the iron.

[0004] Prior art publication CN215560425U discloses a "Sonar-Based Splash and Drying System for Converter Steelmaking." This system provides a splash and dry-back warning output; issues a splash level warning based on the distance between the splash-sensitive slag thickness and a set splash line, and outputs a corresponding splash warning signal to the automated steelmaking system. The automated steelmaking system also uses furnace mouth image processing results to determine whether to adjust the oxygen lance. This new system cannot detect splash and dry-back based on furnace gas flow, employs a single detection method, and cannot predict the trend of splash and dry-back slag activity.

[0005] The publication number is CN113046511A, which discloses "a method for stably controlling splashing and drying of a converter". When adjusting the gun position and adding slag with reference to the CO concentration curve, the operator should understand the reasons for the operation and do it in a timely and stable manner, especially at the basic gun position. After adjusting the gun position, the adjusted gun position is restored to near the basic gun position according to the changes and development trends of the CO concentration curve to ensure a stable refining effect; the operator promptly performs material mixing or gun position operation according to the slag conditions reflected by the changes in the CO concentration curve, effectively controlling the occurrence of abnormal conditions such as drying and splashing; when the decarburization reaction gradually accelerates and becomes the main reaction, if the CO concentration curve in the furnace gas rises faster or slower, it indicates that the foamy slag has not yet formed and the initial slag is not well melted. During the middle stages of blowing, if the CO concentration in the furnace gas continues to increase, it indicates that the slag is drying out. This is because as the FeO content in the slag decreases, the foamy slag surface decreases, reducing carbon monoxide consumption. Once the CO concentration in the furnace gas exceeds 10% of the normal value, the slag is experiencing severe drying out. When the CO concentration in the furnace gas gradually decreases from the normal level, it indicates the onset of slag splashing. This is because the supplied oxygen generates a large amount of iron oxide, which begins to accumulate. As the FeO content in the slag increases, the slag becomes more foamy, causing significant splashing. At this point, the CO concentration in the furnace gas drops to below the normal 10%, or even lower. This invention primarily provides a method for controlling splashing and drying out. It does not quantitatively analyze the relationship between furnace gas and splashing and drying out, nor does it analyze audio, resulting in a relatively simple detection method. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for judging splashing and backdrying in steelmaking by combining furnace gas audio, so as to improve the accuracy of splashing and backdrying judgment, thereby overcoming the shortcomings of traditional methods, better meeting the accuracy requirements of splashing and backdrying detection in the steelmaking process, and providing strong support for the stability, efficiency and high quality of steelmaking production.

[0007] To achieve the above object, the present invention is implemented through the following technical solutions:

[0008] A method for judging steelmaking splashing and drying by combining furnace gas audio frequency, comprising:

[0009] S1. The gas values ​​obtained by analyzing the furnace gas system are stored in corresponding array queues according to the set time intervals;

[0010] S2. Using array queue 1, continuously calculate the difference between the current gas 1 value and the gas values ​​before set time 1, set time 2, and set time 3, to obtain slope 1, slope 2, and slope 3;

[0011] S3. Using array queue 2, continuously calculate the difference between the current gas 2 value and the gas values ​​before set time 1, set time 2, and set time 3, to obtain slope 1, slope 2, and slope 3;

[0012] S4. Subtract the original audio value from 100 to divide the converter noise audio into an audio return dry area, an audio splash area, and an audio normal area. The high-order audio value is the splash area, and the low-order audio value is the return dry area.

[0013] S5. Splashing, drying and trend determination.

[0014] In S1, the gas values ​​are CO values ​​and CO2 values. The array queue includes array queue CO and array queue CO2. The CO value is stored in array queue CO, and the CO2 value is stored in array queue CO2.

[0015] In S5, the splash back and trend determination in the middle of blowing is as follows:

[0016] When the slope value 1 of the CO value is less than -4, the slope value 2 of the CO value is less than -7, the slope value 1 of the CO2 value is less than -1, and the audio is in the splash area, it is determined that splashing has occurred;

[0017] When the slope value of CO value is less than -1, the slope value of CO value is less than -2, the slope value of CO value is less than -3, and the slope value of CO2 value is less than -1, it is determined that there is a slag activity trend;

[0018] When the slope value 1 of the CO value is greater than 1, the slope value 2 of the CO value is greater than 2, the slope value 3 of the CO value is greater than 3, and the slope value 2 of the CO2 value is less than -1, it is determined that there is a trend of returning to dryness;

[0019] When the converter noise audio value is less than 75, it is back-drying.

[0020] The calculation formula for slope one is:

[0021] Slope 1 = (Current gas value - Gas value before set time 1) ÷ (1s) ①

[0022] In formula ①, the unit of time 1 is set to s;

[0023] The calculation formula for slope 2 is:

[0024] Slope 2 = (Current gas value - Gas value before setting time 2) ÷ (1s) ②

[0025] In formula ②, the unit of time 2 is set to s;

[0026] The calculation formula for slope three is:

[0027] Slope 3 = (Current gas value - Gas value before setting time 3) ÷ (1s) ③

[0028] In formula ②, the unit of time 3 is set to s.

[0029] A furnace gas system is installed at the converter flue and the end of the boiler to collect flue gas.

[0030] The interval of 75≤audio value≤85 is the normal audio area, the interval of audio value>85 is the audio splash area, and the interval of audio value<75 is the audio return dry area.

[0031] The time boundary point in the middle stage of blowing is from 4 minutes after the start of blowing to the end of blowing.

[0032] In S4, an audio value greater than the normal audio range is a high-order audio value, and an audio value less than or equal to the normal audio range is a low-order audio value.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. By combining the furnace gas system with the audio slag measurement system and storing and analyzing real-time data from the array queues CO and CO2, it is possible to accurately determine the spattering and backdrying conditions during the steelmaking process. This quantitative data-based judgment method overcomes the inaccuracies of traditional judgments based solely on manual experience or a single audio system, effectively reducing spattering and backdrying caused by misjudgment.

[0035] 2. During the steelmaking process, the slope of the furnace gas curve is continuously calculated in real time to provide early warning of splashing and backdrying trends. For example, when slag activity or backdrying trends are detected, the operator can be notified in time to take appropriate measures to avoid splashing and backdrying, thereby improving the stability and controllability of the steelmaking process.

[0036] 3. Accurately judging and avoiding the occurrence of splashing and back-drying phenomena helps to maintain the normal progress of the decarburization reaction and good dephosphorization effect, thereby improving the quality of steel;

[0037] 4. Splashing can easily cause safety accidents such as burns. This solution can effectively prevent splashing, reducing safety hazards during the steelmaking process, ensuring the personal safety of operators and the safe operation of production equipment. Splashing can cause large heat loss and iron loss in molten iron slag, and generate large amounts of smoke and dust, causing environmental pollution. By avoiding splashing, iron loss and energy consumption can be reduced, smoke and dust emissions can be reduced, and environmental treatment costs can be reduced, thereby reducing overall production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is the real-time curve 1 of converter blowing.

[0039] Figure 2 This is the second real-time curve of converter blowing.

[0040] Figure 3 It is the converter blowing real-time curve three. DETAILED DESCRIPTION

[0041] The present invention will be described in detail below with reference to the accompanying drawings, but it should be noted that the implementation of the present invention is not limited to the following embodiments.

[0042] The following examples are implemented under the premise of the technical solution of the present invention, and provide detailed implementation methods and specific operating processes, but the scope of protection of the present invention is not limited to the following examples. The methods used in the following examples are conventional methods unless otherwise specified.

[0043] Example 1

[0044] A method for judging steelmaking splashing and drying by combining furnace gas audio frequency, specifically comprising:

[0045] S1. Put the converter gas system and converter audio slag measurement system into operation;

[0046] S2. Collect CO value, CO2 value, and audio value of the furnace gas system through OPC or other methods. Add array queue CO and array queue CO2 to the program. The length of each array queue is 60 (first in first out);

[0047] During the entire steelmaking process, the CO value and CO2 value of the furnace gas system are collected once per second and stored in the array queue CO and array queue CO2 respectively. The first-in-first-out principle is adopted to form two array queues with values ​​of 1 second apart for a total of 60 seconds, namely array queue CO and array queue CO2.

[0048] S3. Use the array queues CO and CO2 to index the values ​​in the array queues CO and CO2, and continuously calculate the CO curve and CO2 curve respectively. According to formulas ①, ②, and ③, the 15-second slope value, 30-second slope value, and 60-second slope value are obtained. The calculation formulas are as follows:

[0049] 15-second slope = (current gas value - gas value 15 seconds ago) ÷ (1s) ①

[0050] 30-second slope = (current gas value - gas value 30 seconds ago) ÷ (1s) ②

[0051] 60-second slope = (current gas value - gas value 60 seconds ago) ÷ (1s) ③

[0052] The difference between the current value and the value 15 seconds ago is set as the 15-second slope; the difference between the current value and the value 30 seconds ago is set as the 30-second slope; the difference between the current value and the value 60 seconds ago is set as the 60-second slope;

[0053] S4. Observe the audio value and set the return dry zone, splash zone, and normal zone of the audio value. The contents are as follows:

[0054] The range of 75≤audio value≤85 is the normal audio range;

[0055] The interval where the audio value is greater than 85 is the audio splash zone;

[0056] The interval where the audio value is less than 75 is the audio return dry area;

[0057] S5. During the middle stage of blowing (the time limit of the middle stage of blowing is from 4 minutes after the start of blowing to the end of blowing), splashing back and drying and trend determination are carried out. The contents are as follows:

[0058] Splashing judgment: When the 15-second slope value of CO is less than -4, the 30-second slope value is less than -7, and the 15-second slope value of CO2 is greater than 0.5, and the audio value is in the splashing area, it is determined that splashing has occurred, and the splashing alarm signal is transmitted to the converter screen;

[0059] Slag activity trend determination: When the 15-second slope of CO is less than -1, the 30-second slope is less than -2, and the 60-second slope is less than -3, and the 30-second slope of CO2 is greater than 1, that is, the CO curve is continuously downward and CO2 is slightly upward, it is determined that there is a slag activity trend. At this time, the slag activity trend signal is transmitted to the converter screen;

[0060] Determination of drying trend: In the middle stage of blowing, when the 15-second slope of CO is greater than 1, the 30-second slope is greater than 2, and the 60-second slope is greater than 3, and the 30-second slope of CO2 is less than -1, that is, the CO curve is continuously upward and the CO2 curve is slightly downward, it is determined that there is a drying trend. At this time, the drying trend signal is transmitted to the converter screen;

[0061] Back-drying judgment: When the audio signal is less than 75, it is back-drying, and the back-drying alarm signal is transmitted to the converter screen.

[0062] See Figure 1 When CO continues to rise for a long time and CO2 drops slightly, there is a back-drying trend; when CO drops suddenly and steeply, CO2 rises slightly, and the audio is 85 or above at the same time, splashing occurs; when CO drops continuously for a long time and CO2 rises slightly, it is a slag activity trend; when the audio is less than 75, back-drying occurs.

[0063] Example 2

[0064] A method for judging steelmaking splashing and drying by combining furnace gas audio frequency, specifically comprising:

[0065] S1. Put the converter gas system and converter audio slag measurement system into operation;

[0066] S2. Collect CO value, CO2 value, and audio value of the furnace gas system through OPC or other methods. Add array queue CO and array queue CO2 to the program. The length of each array queue is 60 (first in first out);

[0067] During the entire steelmaking process, the CO value and CO2 value of the furnace gas system are collected once per second and stored in the array queue CO and array queue CO2 respectively. The first-in-first-out principle is adopted to form two array queues with values ​​of 1 second apart for a total of 60 seconds, namely array queue CO and array queue CO2.

[0068] S3. Use the array queues CO and CO2 to index the values ​​in the array queues CO and CO2, and continuously calculate the CO curve and CO2 curve respectively. According to formulas ①, ②, and ③, the 15-second slope value, 30-second slope value, and 60-second slope value are obtained. The calculation formulas are as follows:

[0069] 15-second slope = (current gas value - gas value 15 seconds ago) ÷ (1s) ①

[0070] 30-second slope = (current gas value - gas value 30 seconds ago) ÷ (1s) ②

[0071] 60-second slope = (current gas value - gas value 60 seconds ago) ÷ (1s) ③

[0072] The difference between the current value and the value 15 seconds ago is set as the 15-second slope; the difference between the current value and the value 30 seconds ago is set as the 30-second slope; the difference between the current value and the value 60 seconds ago is set as the 60-second slope;

[0073] S4. Observe the audio value and set the return dry zone, splash zone, and normal zone of the audio value. The contents are as follows:

[0074] The range of 75≤audio value≤85 is the normal audio range;

[0075] The interval where the audio value is greater than 85 is the audio splash zone;

[0076] The interval where the audio value is less than 75 is the audio return dry area;

[0077] S5. Blowing is divided into the initial blowing stage, the middle blowing stage and the final blowing stage. The beginning of blowing is the silicon-manganese reaction stage, CO and CO2 will rise; after rising to the peak, CO will remain at a high level, and CO2 will slowly decrease and remain at a certain position. In the middle blowing stage, Figure 2 In the middle stage of blowing, the decarburization rate indicated by the CO and CO2 curves is stable, with no obvious splashing or drying back. However, in most cases, splashing, drying back, and corresponding trend changes will occur. In this case, splashing, drying back, and trend determination are as follows:

[0078] The basis for determining splashing is that the CO curve drops very steeply, while CO2 rises slightly, indicating that the CO gas in the molten pool is suddenly blocked by the slag, accumulating energy and being judged as splashing. Quantified, when the CO 15-second slope is less than -5, the 30-second slope is less than -7, and the 15-second slope of CO2 is +0.5, it is judged as splashing, and the splashing alarm signal is transmitted to the converter screen;

[0079] Determining slag activity trends: If the CO curve decreases slowly but continuously for an extended period, while CO2 continues to rise, this indicates that not all of the oxygen used in blowing is being used to produce CO and CO2, but rather that some is being used to increase iron oxide, indicating a slag activity trend. This is quantified by the following: when the 15-second slope is less than -1.5 but greater than -3, the 30-second slope is less than -2.5 but greater than -5, the 60-second slope is less than -3.5 but greater than -10, and the 30-second slope of CO2 is greater than 1.5, there is a slag activity trend. At this point, the slag activity trend signal is transmitted to the converter screen.

[0080] Back-drying judgment: When the audio signal is less than 75, it is back-drying, and the back-drying alarm signal is transmitted to the converter screen.

[0081] See Figure 3 When CO suddenly drops steeply, the 15-second and 30-second slope data drop a lot, CO2 rises slightly, and the audio is 85 or above at the same time, splashing occurs; when the CO 15-second, 30-second, and 60-second data show a continuous decline, and CO2 rises slightly, it is a slag activity trend; when the audio is less than 75, backdrying occurs.

[0082] The present invention combines the furnace gas system with the audio slag measuring system, and uses the real-time data of the array queue CO and the array queue CO2 to store and analyze, which can accurately judge the splashing and back-drying conditions in the steelmaking process. This judgment method based on quantitative data overcomes the inaccuracy of traditional judgment based on manual experience or a single audio system, and effectively reduces the splashing and back-drying caused by misjudgment. In the steelmaking process, by continuously calculating the slope value of the furnace gas curve in real time, early warning of splashing and back-drying trends is given. For example, when a slag activity trend or back-drying trend is detected, the alarm can be notified in time. This solution effectively prevents splashing, which can easily lead to safety incidents such as burns, and reduces potential safety hazards during steelmaking, ensuring the personal safety of operators and the safe operation of production equipment. Splashing can lead to significant heat and iron losses in the molten iron slag, as well as the generation of large amounts of smoke and dust that pollute the environment. Avoiding splashing can reduce iron losses, energy consumption, smoke emissions, and environmental treatment costs, ultimately lowering overall production costs.

Claims

1. A method for judging steelmaking splashing and drying by combining furnace gas audio, characterized in that: include: S1. The gas values ​​obtained by analyzing the furnace gas system are stored in corresponding array queues according to the set time intervals; S2. Using array queue 1, continuously calculate the difference between the current gas 1 value and the gas values ​​before set time 1, set time 2, and set time 3, to obtain slope 1, slope 2, and slope 3; S3. Using array queue 2, continuously calculate the difference between the current gas 2 value and the gas values ​​before set time 1, set time 2, and set time 3, to obtain slope 1, slope 2, and slope 3; S4. Subtract the original audio value from 100 to divide the converter noise audio into an audio return dry area, an audio splash area, and an audio normal area. The high-order audio value is the splash area, and the low-order audio value is the return dry area. S5. Splashing, drying and trend determination.

2. The method for judging steelmaking splashing and drying by combining furnace gas audio according to claim 1 is characterized in that: In S1, the gas values ​​are CO values ​​and CO2 values, and the array queue includes array queue CO and array queue CO2. The CO value is stored in array queue CO, and the CO2 value is stored in array queue CO2.

3. The method for judging steelmaking splashing and drying by combining furnace gas audio according to claim 2, characterized in that: In S5, the splash back and trend determination in the middle of blowing is as follows: When the slope value 1 of the CO value is less than -4, the slope value 2 of the CO value is less than -7, the slope value 1 of the CO2 value is less than -1, and the audio is in the splash area, it is determined that splashing has occurred; When the slope value of CO value is less than -1, the slope value of CO value is less than -2, the slope value of CO value is less than -3, and the slope value of CO2 value is less than -1, it is determined that there is a slag activity trend; When the slope value 1 of the CO value is greater than 1, the slope value 2 of the CO value is greater than 2, the slope value 3 of the CO value is greater than 3, and the slope value 2 of the CO2 value is less than -1, it is determined that there is a trend of returning to dryness; When the converter noise audio value is less than 75, it is back-drying.

4. The method for judging steelmaking splashing and drying by combining furnace gas audio according to claim 1, characterized in that: The calculation formula for slope one is: Slope 1 = (Current gas value - Gas value before set time 1) ÷ (1s) ① In formula ①, the unit of set time 1 is s; The calculation formula for slope 2 is: Slope 2 = (Current gas value - Gas value before setting time 2) ÷ (1s) ② In formula ②, the unit of setting time 2 is s; The calculation formula for slope three is: Slope 3 = (Current gas value - Gas value before setting time 3) ÷ (1s) ③ In formula ②, the unit of setting time 3 is s.

5. The method for judging steelmaking splashing and drying by combining furnace gas audio according to claim 1 is characterized in that: A furnace gas system is installed at the converter flue and the end of the boiler to collect flue gas.

6. The method for judging steelmaking splashing and drying by combining furnace gas audio according to claim 1, characterized in that: The interval of 75≤audio value≤85 is the normal audio area, the interval of audio value>85 is the audio splash area, and the interval of audio value<75 is the audio return dry area.

7. The method for judging steelmaking splashing and drying by combining furnace gas audio according to claim 3 is characterized in that: The time point of the middle stage of blowing is from 4 minutes after the start of blowing to the end of blowing.

8. The method for judging steelmaking splashing and drying by combining furnace gas audio frequency according to claim 3 is characterized in that: In S4, an audio value greater than the normal audio range is a high-order audio value, and an audio value less than or equal to the normal audio range is a low-order audio value.

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