Quantum electric furnace molten steel quantity prediction and charging quantity recommendation method based on liquid level depth

Abstract

This invention relates to a method for predicting the amount of steel retained in a quantum electric furnace and recommending the amount of hot metal charged based on the liquid level depth. A steel retention prediction model is constructed by adjusting the liquid level depth and furnace lining erosion. A scrap and hot metal charging recommendation model is constructed based on ambient temperature, scrap compensation coefficient α, and hot metal compensation coefficient β. Depending on production continuity, if production is continuous, the K value from the previous heat is selected and called upon. 侵蚀 Calculate M 留钢 α, β, and abnormal erosion correction; if production is discontinuous, read the liquid level depth H, furnace age N, and current scrap steel grade, steel type, and applicable standard to calculate the initial K. 侵蚀 Recommended value. Then, calculate R. 新 and the next batch of M 留钢量 The coefficients are stored, and finally, the charge amount M for the next furnace is calculated. 废钢 M 铁水 This invention solves the problem of balancing the amount of molten steel in the furnace caused by the inability to directly weigh the amount of steel left, and achieves stable control of the total amount of molten steel.

Description

Technical Field

[0001] This invention relates to a method for predicting the amount of steel to be retained in a quantum electric arc furnace and recommending the amount to be charged based on the liquid level depth, belonging to the technical field of quantum electric arc furnace steelmaking. Background Technology

[0002] In quantum electric arc furnace steelmaking, the steel retention operation is a core process for ensuring furnace thermal balance, optimizing the smelting cycle, and extending furnace lining life. The amount of steel retained typically relies on operator experience for estimation. Operators manually observe the current liquid level through the observation port to roughly estimate the amount of steel remaining in the furnace. However, due to intense reactions or environmental changes within the furnace, and numerous influencing factors such as fluctuations in scrap steel quality and yield, furnace lining erosion, and the observer's position, estimation errors are frequent, leading to inaccurate addition of scrap steel and molten iron, thus affecting production stability. Traditional steel tapping weight calculation models have the following main drawbacks: 1. Lack of liquid level monitoring: In the siphon steel discharge mode, the amount of steel retained depends on empirical estimation and does not take into account real-time liquid level depth data, resulting in a large error.

[0003] 2. Weight calculation deviation: The amount of steel to be retained was not dynamically incorporated into the material balance model. The amount to be loaded was estimated manually, resulting in a large deviation. The ratio of scrap steel to molten iron was inaccurate, which delayed production.

[0004] 3. Neglecting the impact of furnace lining erosion: Furnace lining erosion caused by furnace age will change the furnace internal volume, but no erosion coefficient prediction mechanism has been established.

[0005] To address the aforementioned shortcomings, this invention provides a method for predicting the amount of steel to be retained and recommending the amount of molten iron to be charged in a quantum electric furnace based on liquid level depth. This method dynamically predicts the amount of steel to be retained and recommends the amount of scrap steel and molten iron to be charged in the next heat, thereby achieving scientific production management. Summary of the Invention

[0006] To address the aforementioned problems, this invention discloses a method for predicting the amount of steel to be retained and recommending the charging amount in a quantum electric furnace based on liquid level depth. The specific technical solution is as follows: A method for predicting the amount of steel to be retained and recommending the charging amount in a quantum electric furnace based on liquid level depth includes the following steps: Step 1: During the tapping stage of the quantum electric furnace, determine whether it is continuous production. If it is continuous production, proceed to step 7 after executing steps 2-4. If it is discontinuous production, proceed to step 7 after executing steps 5-6. Step 2: Read historical data and parameter tables, and calculate based on information such as the erosion coefficient of the previous furnace and the furnace age of the current furnace. Book Furnace lining erosion rate K 侵蚀 ; Step 3: Correct abnormal erosion and calculate the corrected new furnace lining erosion rate K. 修正 And the amount of steel retained in this heat; Step 4: Based on the smelting information of consecutive furnaces, solve the system of equations to calculate the scrap steel compensation coefficient α and the molten iron compensation coefficient β; Step 5: Read the liquid level depth H, furnace age N, and current scrap steel grade, steel type, and applicable standard; Step 6: Calculate the initial furnace lining erosion rate K 首次侵蚀 ; Step 7: Calculate the current effective radius R of the furnace. 有效 ; Step 8: Using the current effective radius R of the furnace, the liquid level depth H-weight mapping within the furnace is used. 有效 Calculate the next batch M 留钢量 ; Step 9: Store data and update the parameter table; Step 10: Specify the scrap steel loading amount M for the next heat. 废钢 And the amount of molten iron charged M 铁水 The number of recommendations; Step 11: Loop back to step 1.

[0007] Furthermore, the amount of steel retained in step 2, M 留钢量 The calculation method is as follows: The liquid level depth H is monitored in real time using a laser rangefinder, and the volume of molten steel is calculated based on a cylindrical furnace model. The amount of steel left in the furnace, M 留钢量 for: , In the formula, R 有效 The current effective radius of the furnace lining needs to be adjusted based on the corrosion rate of the furnace lining. ρ Let be the density of molten steel, and be a known quantity.

[0008] Furthermore, the current effective radius of the furnace R 有效 The correction method is as follows: , In the formula, R 初始 The original design radius for adding refractory material to the furnace lining is determined based on the furnace lining structural design parameters. K 侵蚀 The erosion rate of the furnace lining represents the increase in furnace radius per heat caused by slag erosion, chemical corrosion, or wear from scrap steel impacts. N 炉龄 The cumulative furnace age, i.e. the number of times the smelting furnace has been replaced after the refractory material has been replaced, is used to quantify the cumulative degree of erosion effect. The effective radius of the furnace is dynamically updated through formula (2) to compensate for the furnace volume error caused by erosion.

[0009] Furthermore, the erosion rate K 侵蚀 The process of obtaining it is as follows: The erosion rate of the furnace lining is calculated by using the liquid level difference ΔH at tapping and the actual tapping weight. K 侵蚀 : , In equation (3), H 前、 H 后 The heights of the liquid level in the furnace before and after tapping are known quantities, and ΔH is obtained according to formula (3). In equation (4), M 出钢量 The actual weight of the steel tapped in the current heat is known by weighing it in the ladle after the furnace. ΔR is obtained according to formula (4). 实际 ; In equation (5), N is the cumulative furnace age, which is a known quantity. Substituting ΔR into the equation... 实际 Calculate K 侵蚀 ; Furthermore, in terms of erosion rate K 侵蚀 During the process, a deviation trigger threshold is set: the deviation between two consecutive furnace batches is expressed as... When the deviation between the actual and theoretical weight exceeds 5%, it is determined that there is abnormal erosion in the furnace or model error, and the furnace lining erosion rate correction needs to be triggered. The formula for furnace lining erosion rate correction is: , In equation (6), A value of 0.7 is generally used to closely reflect the current erosion trend; K 修正 Substituting into formula (2), we obtain the corrected R. 有效 .

[0010] Furthermore, step 3 specifically involves: The weight of molten steel before tapping in a quantum electric furnace is the sum of scrap steel, molten iron, and the amount of steel left over from the previous furnace. The amount of steel left over after tapping is the weight of molten steel before tapping minus the weight of the tapped steel. To calculate the compensation coefficient for scrap steel and molten iron, data from three consecutive furnace runs in historical data are used to solve a simultaneous equation: , In equation (7), the subscripts 0, 1, and 2 represent any three consecutive furnaces. The data for each furnace in equation (7) are process data retrieved from the database. The information added for the first two furnaces is retrieved. M 留钢量0 M 废钢1 M 铁水1 M 出钢量1 All are known quantities. Based on the liquid level depths H and K after the two furnaces of steelmaking, M is obtained by substituting them into formula (1). 留钢量1 and M留钢量2 M in the last of three consecutive furnace batches 废钢2 M 铁水2 M 出钢量2 All of these are known quantities. Substitute them into equation system (7) to solve for the current scrap steel compensation coefficient α and molten iron compensation coefficient β. α Related to oxidation loss rate; according to the scrap steel grading system, the oxidation loss of scrap steel of the same grade fluctuates less; molten iron compensation coefficient. β It is related to the slag material in the furnace, the stirring and reaction time, and especially to the process specifications, namely the steel grade and the standards implemented.

[0011] Further, step 6 calculates the initial erosion rate K. 首次侵蚀 Recommendation: When the program starts, based on the current furnace age N parameter, use the α, β, and K parameters stored historically for each furnace. 侵蚀 Production information such as furnace age N is used to find similar production data for different heats. If the scrap grade, liquid level depth H, and furnace age N of the current heat are the same as a historical heat, then its α, β, and K are used. 侵蚀 R 有效 Parameters, but to prevent K 侵蚀 To mitigate the error from a single attempt, we search for the 10 most relevant historical data. The criteria for this search are: consistent scrap steel grade and furnace age; liquid level depth determined using a distance formula; and for data with the same distance, sorting by time to find the 10 closest K values. 侵蚀 Then these 10 K 侵蚀 The average erosion value is used as a temporary recommended value for erosion. Based on the current furnace age N data, we search for 10 historical furnaces K with similar furnace ages N, α, and β. 侵蚀 Combining the following formula (8), the average value is the initial erosion rate K. 首次侵蚀 Recommended value: , K is calculated according to formula (8) 首次侵蚀 Substituting into formula (2) to solve for R 有效 , will R 有效 Substitute into formula (1) to predict the amount of steel left in the furnace for the first time.

[0012] Furthermore, step 8 specifically involves using the R obtained in step 7. 有效 Substitute into formula (1) to calculate the current furnace batch M. 留钢量 .

[0013] Furthermore, the calculation process for the next furnace charge is as follows:

[0014] After tapping, based on the calculated amount of steel remaining in the furnace and the maximum amount of molten steel the furnace can hold, the recommended amounts of scrap steel and molten iron to be charged for the next heat are determined. The specific method is as follows: First, determine the liquid level limit based on the furnace design parameters. H Based on the corresponding theoretical volume, calculate the maximum weight of molten steel, subtract the current amount of steel to be retained, and finally calculate M for the next heat according to the following formula (9). 装入量 , , at the same time M 装入量 It is further divided into two parts: molten iron and scrap steel. The weight of each part is precisely adjusted according to its respective compensation coefficient. , Furthermore, to provide more precise guidance for manual labor, based on the impact of scrap steel quantity and ambient temperature on thermodynamic balance, the proportion of molten iron is increased to compensate for the temperature drop and preheating energy consumption caused by insufficient scrap steel preheating. , Wherein, HM% represents the mass percentage of molten iron, indicating... M 装入量 The proportion of China Railway's water supply T Let M be the ambient temperature in °C. Solving equation (10) simultaneously, we finally obtain M. 铁水 : , This invention addresses the challenges of modeling furnace lining erosion by using a laser rangefinder to measure the liquid level depth during tapping in real time. This allows for the establishment of a furnace lining erosion correction model, which accurately predicts the amount of steel to be retained and the amount of scrap steel and molten iron required for the next heat.

[0015] The beneficial effects of this invention are: This invention is based on real-time monitoring of liquid level depth and dynamic prediction of the amount of steel to be retained, and recommends the amount of scrap steel and molten iron to be charged in the next heat. It is especially suitable for quantum electric furnaces that use siphon tapping, and solves the problem of dynamic balance between scrap steel and retained steel caused by the inability to directly weigh the amount of steel to be retained, so as to achieve stable control of the total amount of molten steel throughout the entire production cycle. Attached Figure Description

[0016] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0017] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0018] Combined with appendix Figure 1 As can be seen, the specific process of this invention is as follows: 1. During the tapping stage of this furnace, determine whether it is continuous production by reading historical data and parameter tables.

[0019] 2. If production is continuous, read historical data and parameter tables, and calculate based on information such as the erosion coefficient of the previous batch and the age of the current batch. Book Furnace lining erosion rate K 侵蚀 .

[0020] 3. Correct abnormal erosion and calculate the corrected new furnace lining erosion rate K. 修正 And the amount of steel retained in this heat.

[0021] 4. Based on the smelting information of consecutive furnaces, solve the system of equations to calculate the scrap steel compensation coefficient α and the molten iron compensation coefficient β.

[0022] 5. If production is not continuous, read the liquid level depth H and furnace age N or the current scrap steel grade, steel type and applicable standard.

[0023] 6. Calculate the first time K 侵蚀 Highly recommended.

[0024] 7. Calculation R 新 .

[0025] 8. Calculate the next batch using liquid level depth-weight mapping. M 留钢量 .

[0026] 9. Store data and update parameter tables.

[0027] 10. Calculate the charge amount for the next furnace. M 废钢 , M 铁水 .

[0028] A specific embodiment of the present invention is given below: The maximum design capacity of the quantum electric furnace is Mmax = 180t, and the initial furnace radius R (including refractory material) is R. 初始 =3m, molten steel density ρ=7.2t / m³, height limit of quantum electric furnace Current furnace age N=55, furnace ambient temperature T=20℃, previous furnace erosion coefficient =0.0022m, the weight of scrap steel added in this furnace. =62.05 tons, weight of molten iron added =32.36 tons, the liquid level depth before tapping is =0.79 meters, depth of liquid surface after tapping =0.39 meters, steel output weight =88.8 tons.

[0029]

[0030] K 当前 K represents the erosion rate of the current furnace run. 上一炉 This indicates the erosion rate of the previous batch. , K 修正 This indicates the corrected erosion rate for the current furnace run. , , , , Query the information for the previous two batches, including the batch before that. =86.3 tons; weight of scrap steel added in the previous batch The weight of the added molten iron is 62.88 tons. The steel output weight was 32.81 tons. =90 tons, based on the depth of the liquid surface after tapping. =0.392 meters and , and thus =86.35 tons, solved for... =0.923, =0.976.

[0031] , In summary, this patented method can be directly applied to industrial workshop production, directly guiding production, avoiding empiricism, accurately providing the amount of molten iron and scrap steel to be added for the next batch, improving production predictability, avoiding energy waste and product defects caused by unscientific composition, and achieving precision production.

[0032] Those skilled in the art will understand that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0033] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A method for predicting the amount of steel to be retained and recommending the amount to be charged in a quantum electric furnace based on liquid level depth, characterized in that, Includes the following steps: Step 1: During the tapping stage of the quantum electric furnace, determine whether it is continuous production. If it is continuous production, proceed to step 7 after executing steps 2-4. If it is discontinuous production, proceed to step 7 after executing steps 5-6. Step 2: Read historical data and parameter tables, and calculate the erosion rate K of the furnace lining based on the erosion coefficient of the previous furnace and the furnace age information of the current furnace. 侵蚀 The erosion rate K 侵蚀 The process of obtaining it is as follows: The erosion rate of the furnace lining is calculated by using the liquid level difference ΔH at tapping and the actual tapping weight. K 侵蚀 : ， In the formula, R 初始 Adding the original design radius of the refractory to the furnace lining, H 前、 H 后 These represent the liquid level height in the furnace before and after tapping, M. 出钢量 N represents the actual weight of steel tapped in the current heat, and N represents the cumulative furnace age. Step 3: Correct abnormal erosion and calculate the corrected new furnace lining erosion rate K. 修正 And the amount of steel retained in this heat: In erosion rate K 侵蚀 During the process, a deviation trigger threshold is set, and the deviation between two consecutive furnace batches is expressed as follows: When the deviation between the actual and theoretical weight exceeds 5%, it is determined that there is abnormal erosion in the furnace or model error, and the furnace lining erosion rate correction needs to be triggered. The formula for furnace lining erosion rate correction is: ， In equation (7), We take 0.7 to closely reflect the current erosion trend. This indicates the current furnace erosion rate. Indicates the erosion rate of the previous furnace; Step 4: Based on the smelting information from consecutive furnace runs, solve the system of equations to calculate the scrap steel compensation coefficient. Iron molten metal compensation coefficient : The weight of the molten steel before tapping from the quantum electric furnace is M (the weight of the scrap steel). 废钢 molten iron M 铁水 and the amount of steel left in the furnace M 留钢量 The sum of these factors, along with the amount of steel remaining in the furnace after tapping, is the weight of the molten steel before tapping minus the weight of the tapped steel. This is used to calculate the compensation coefficient for scrap steel. Compensation coefficient with molten iron We selected data from three consecutive furnace runs in the historical data and solved the following simultaneous equations: ， In equation (6), the subscripts 0, 1, and 2 represent any three consecutive furnace batches. The data for these three consecutive furnace batches are all process data retrieved from the database. M 留钢量0 M 废钢1 M 铁水1 M 出钢量1 M 废钢2 M 铁水2 M 出钢量2 All are known quantities; Step 5: Read the liquid level depth H, furnace age N, and current scrap steel grade, steel type, and applicable standard; Step 6: Calculate the initial furnace lining erosion rate K 首次侵蚀 : Based on the current furnace age N data, then find the furnace age N, , Also similar in history 10 furnaces K 侵蚀 Combining the following formula (8), the average value is the initial erosion rate K. 首次侵蚀 Recommended value: ， Step 7: Calculate the current effective radius R of the furnace. 有效 The current effective radius of the furnace. R 有效 The correction method is as follows: ， In the formula, K 侵蚀 The erosion rate of the furnace lining; Step 8: Using the current effective radius R of the furnace, the liquid level depth H-weight mapping within the furnace is used. 有效 Calculate the next batch M 留钢量 : The volume of molten steel was calculated based on a cylindrical furnace model. The amount of steel left in the furnace, M 留钢量 for, ， In the formula, R 有效 The current effective radius of the furnace. Density of molten steel; Step 9: Store data and update the parameter table; Step 10: Specify the scrap steel loading amount M for the next heat. 废钢 And the amount of molten iron charged M 铁水 Recommended quantity: Determine the theoretical volume corresponding to the liquid level limit based on the furnace design parameters, calculate the maximum weight of molten steel, subtract the current amount of steel to be retained, and calculate M for the next heat. 装入量 ; Step 11: Loop back to step 1.

2. The method for predicting the amount of steel to be retained and recommending the amount to be charged in a quantum electric furnace based on liquid level depth as described in claim 1, characterized in that, The liquid level depth H is monitored in real time using a laser rangefinder.

3. The method for predicting the amount of steel to be retained and recommending the amount to be charged in a quantum electric furnace based on liquid level depth as described in claim 1, characterized in that, K 侵蚀 Substituting into formula (2), based on the furnace life of the two furnaces, calculate the two R values. 有效 , take two R 有效 Substituting into formula (1), calculate the amount of steel retained M for the two tests. 留钢量 .

4. The method for predicting the amount of steel to be retained and recommending the amount to be charged in a quantum electric furnace based on liquid level depth as described in claim 1, characterized in that, Step 6: Calculate the initial erosion rate K 首次侵蚀 Recommendation: When the program starts, based on the current furnace age N parameter, use the historical data for each furnace cycle. , K 侵蚀 The production information, including furnace age N, is used to find similar production data. If the scrap grade, liquid level depth H, and furnace age N of the current furnace are the same as a historical furnace, then that furnace is used. , K 侵蚀 R 有效 Parameters, but to prevent K 侵蚀 To mitigate the error from a single attempt, we search for the 10 most relevant historical data. The criteria for this search are: consistent scrap steel grade and furnace age; liquid level depth determined using a distance formula; and for data with the same distance, sorting by time to find the 10 closest K values. 侵蚀 Then these 10 K 侵蚀 The average erosion value is used as a temporary recommended value for erosion. K is calculated according to formula (8) 首次侵蚀 Substituting into formula (2) to solve for R 有效 , will R 有效 Substitute into formula (1) to predict the amount of steel left in the furnace for the first time.

5. The method for predicting the amount of steel to be retained and recommending the amount to be charged in a quantum electric furnace based on liquid level depth, as described in claim 1, is characterized in that... Step 8 specifically involves using the R obtained in step 7. 有效 Substitute into formula (1) to calculate the current furnace batch M. 留钢量 .

6. The method for predicting the amount of steel to be retained and recommending the amount to be charged in a quantum electric furnace based on liquid level depth, as described in claim 5, is characterized in that... The calculation process for the next furnace charge is as follows: After tapping, based on the calculated amount of steel remaining in the furnace and the maximum amount of molten steel the furnace can hold, the recommended amount of scrap steel and molten iron to be charged for the next heat is made. The specific method is as follows: First, calculate the M for the next heat according to formula (9). 装入量 , ， at the same time M 装入量 It is further divided into molten iron and scrap steel, and their respective weights are adjusted according to their compensation coefficients. ， To provide more precise guidance for manual labor, based on the impact of scrap steel quantity and ambient temperature on thermodynamic balance, the proportion of molten iron was increased to compensate for the temperature drop and preheating energy consumption caused by insufficient scrap steel preheating. ， Wherein, HM% represents the mass percentage of molten iron, indicating... M 装入量 The proportion of China Railway's water supply T Let M be the ambient temperature in °C. Solving equation (10) simultaneously, we finally obtain M. 铁水 : 。

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