Method for predicting components of LF refined molten steel

Abstract

The invention belongs to the technical field of steel smelting, and particularly relates to an LF refining molten steel component prediction method. The method comprises the following steps: defining and dividing an effective reaction area in the LF refining process by utilizing an effective equilibrium reaction area model; determining related parameters of the divided reaction zones and the mass of each phase participating in the local equilibrium reaction; and a FactSage thermodynamic calculation software macro-processing technology is utilized to realize molten steel component prediction in the LF refining process. The prediction method does not need a large amount of data for training, dynamics simulation is only carried out under the condition of limited data support, the number of trial and error times can be greatly reduced, the production efficiency is improved, and reduction of the production cost and improvement of the molten steel quality are facilitated. Based on the multiphase physical and chemical reaction principle, the method comprehensively considers the interaction between phases in the LF refining process, practically corresponds to the actual reaction process of LF refining, can adapt to sudden data fluctuation in actual production, and accurately predicts the component change of the LF refined molten steel.

Description

Technical Field

[0001] The invention belongs to the technical field of steel smelting, and in particular relates to a method for predicting the composition of LF refined molten steel. Background Art

[0002] In the steelmaking process, the LF refining furnace plays a vital role in refining molten steel. It is not only a bridge connecting the previous and next processes, but also a "regulator" for the entire process of steel production. After the initial refining, the temperature and composition of the molten steel may fluctuate, and the task of LF refining is to adjust these fluctuations to ensure that molten steel that meets the standards is provided for subsequent refining or continuous casting processes. However, in actual operation, LF refining has the following problems: Due to the unstable state of the molten steel at the end of the initial refining, the selection and addition amount of deoxidizers, slag-making materials and alloys, and the control of argon blowing flow rate during the LF refining process often depend on the judgment of the operator, which may cause large fluctuations in the dynamic conditions of the molten steel, the slag-forming properties of the slag, and the composition of the molten steel during LF refining, thereby affecting the refining effect. Even under the same process and refining slag addition conditions, the reactions that occur when smelting different steel grades are not the same, which significantly increases the uncertainty of the composition of the molten steel during the LF refining process.

[0003] Chinese patent CN116469481A discloses a method for predicting the composition of LF refined steel liquid based on the XGBoost algorithm, which uses the XGBoost algorithm to predict the contents of three elements, Al, Si, and Mn, in the composition of LF refined steel liquid. The specific steps are: first, collect the initial parameters of LF refining and preprocess the data; then, build an XGBoost model through the training set, when the model evaluation is qualified, process the model prediction results, and collect actual production data for a period of time in the future, incorporate it into the sample data and store it in the database; when the model evaluation data is unqualified, the model returns to the data preprocessing step. However, this prediction method relies on a large data set. For new process conditions or new steel grades, it is difficult to apply this type of method for prediction due to the lack of sufficient data support; this prediction method only predicts the composition of steel liquid at the surface level of the data, and cannot go deep into the microscopic level of the interaction between each element and each phase. In actual operation, when there is a large fluctuation in individual elements, this prediction method will fail. In summary, the LF refined steel liquid composition prediction method based on the XGBoost algorithm has great limitations. Summary of the invention

[0004] In view of this, the present invention provides a method for predicting the composition of LF refined molten steel. The prediction method provided by the present invention closely fits the actual production needs and can maintain the accuracy of prediction under unstable process conditions.

[0005] In order to solve the above technical problems, the present invention provides a method for predicting the composition of LF refined molten steel, comprising the following steps:

[0006] Step 1: Based on the effective equilibrium reaction zone model, the reactions occurring in the LF refining process are defined and divided in the form of reaction zones; the reaction zones include: the electrode carburizing zone into the molten steel, the alloy dissolving reaction zone in the molten steel, the inclusion floating zone, the refining slag dissolving in the slag reaction zone, the refractory and molten steel reaction zone, the refractory and slag reaction zone, the molten steel and slag reaction zone, the molten steel mixing zone, and the slag mixing zone;

[0007] Step 2: Determine the first molten steel composition and mass M according to the input molten steel composition and mass 钢液1 and the first inclusion composition and mass M 夹杂物1 , according to the first inclusion composition, mass M 夹杂物1 Get the mass of inclusions entering the inclusion floating area within the time step Δm 夹杂物 and the mass M of inclusions entering the alloy dissolution reaction zone in the molten steel 夹杂物1 -Δm 夹杂物 ;

[0008] Calculate the carburizing mass Δm of the electrode into the carburizing zone of the molten steel within the time step according to the set power supply system 碳 , according to the carburizing mass Δm 碳 and the first molten steel composition and quality M 钢液1 Determine the composition and mass M of the second molten steel 钢液2 ;

[0009] According to the input alloy addition system and the second molten steel composition, quality M 钢液2 The composition and mass M of the second inclusion in the alloy dissolution reaction zone in the molten steel are obtained respectively. 夹杂物2 and the composition and quality M of the third molten steel 钢液3 ;

[0010] According to the refractory composition and dissolution rate, the mass of refractory participating in the reaction between refractory and molten steel in the time step is calculated respectively. 耐材→钢液 and the mass of refractory material participating in the reaction between refractory material and slag Δm 耐材→炉渣 , and obtain the composition and mass M of the third inclusion in the reaction zone between the refractory and the molten steel 夹杂物3 The composition and mass M of the fourth molten steel in the reaction zone between the refractory and the molten steel 钢液4 ;

[0011] Determine the first slag composition and mass M according to the input slag composition and mass 炉渣1 , according to the first slag composition, mass M 炉渣1 , the set refined slag feeding system and the inclusions floating in the inclusion floating area obtain the refined slag dissolved in the slag reaction area, the second slag composition, mass M炉渣2 ; According to the mass of the refractory material participating in the reaction in the reaction zone between the refractory material and the slag Δm 耐材→炉渣 and the second slag composition and mass M 炉渣2 Get the third slag composition and mass M in the reaction zone between refractory and slag 炉渣3 ;

[0012] According to formula 1, the mass of molten steel participating in the reaction in the molten steel and slag reaction zone within the time step is calculated as Δm 钢液 , according to formula 2, calculate the mass Δm of slag involved in the reaction of molten steel and slag reaction zone within the time step 炉渣 ;

[0013] Δm 钢液 =k 钢液 A 炉底 ρ 钢液 Δt Formula 1,

[0014] Δm 炉渣 =k 炉渣 A 炉底 ρ 炉渣 Δt Formula 2,

[0015] Among them, k 钢液 is the mass transfer coefficient of the steel liquid element, m·s -1 ;k 炉渣 is the mass transfer coefficient of the slag component, m·s -1 ; A 炉底 is the geometric area of ​​the steel liquid surface in the LF refining furnace, m 2 ρ 钢液 is the density of molten steel, kg·m -3 ρ 炉渣 is the slag density, kg·m -3 ; Δt is the time step, s;

[0016] In the time step, the mass of molten steel entering the molten steel mixing zone is Δm 新钢液 and M 钢液4 -Δm 钢液 , the mass of inclusions entering the mixing zone of molten steel is M 夹杂物2 、M 夹杂物3 and Δm 新夹杂物 ; The mass of slag entering the slag mixing zone is Δm 新炉渣 and M 炉渣3 -Δm 炉渣 ;

[0017] According to the reaction process of each reaction zone, a macro processing code in mac format is written to add alloy addition system, steel liquid composition and quality, refractory composition, slag composition and quality, power supply system, refined slag feeding system, Δm 碳 , Δm 夹杂物 、M 夹杂物1-Δm 夹杂物 , Δm 耐材→钢液 , Δm 耐材→炉渣 , Δm 钢液 , Δm 炉渣 、M 钢液4 A Δm 钢液 and M 炉渣3 -Δm 炉渣 Perform macro processing coding and use FactSage to perform simulation calculations to obtain the phase composition and mass of each reaction zone after reaction;

[0018] Step 3: Repeat the operation of step 2 x times. When x△t is greater than or equal to the total LF refining time t 总 The calculation stops when the LF furnace smelting end point is output, and the molten steel composition and mass M 钢液 , the inclusion composition and quality M at the end of LF furnace smelting 夹杂物 The slag composition and quality M at the end of LF furnace smelting 炉渣 .

[0019] Preferably, the mass transfer coefficient of steel is calculated according to Formula 3, and the mass transfer coefficient of slag components is calculated according to Formula 4:

[0020] k 钢液 =4×10 -6 ε 1.4 H 钢液 Formula 3;

[0021]

[0022] Where ε is the stirring energy, W·t -1 ;H 钢液 is the height of molten steel in LF refining furnace, m.

[0023] Preferably, the stirring energy is calculated according to Formula 5:

[0024]

[0025] Where n is the molar gas flow rate, mol·s -1 ; R is the ideal gas constant, J·mol -1 ·K -1 ; T is temperature, K; M 钢液4 The unit is t; P t is the total gas pressure at the bottom of the ladle, Pa; P0 is the gas pressure on the melt surface, Pa.

[0026] Preferably, the Δm 夹杂物 According to formula 6, we can get:

[0027] Δm 夹杂物 =r fl ×M夹杂物1 Formula 6;

[0028] Among them, r fl is the inclusion removal rate.

[0029] Preferably, the r fl According to formula 7, we can get:

[0030] r fl =4.2×10 -4 ε 0.2 Formula 7;

[0031] Preferably, the Δm 耐材→钢液 According to formula 8, we can get:

[0032] Δm 耐材→钢液 =V1A 钢液侧壁面 Δt Formula 8;

[0033] Where V1 is the dissolution rate of the refractory in the molten steel, kg·m -2 ·s -1 , A 钢液侧壁面 is the area of ​​the molten steel contacting the side wall of the refining furnace, m 2 .

[0034] Preferably, the A 钢液侧壁面 According to formula 9, we can get:

[0035] A 钢液侧壁面 =2πRH 钢液 Formula 9;

[0036] Where R is the radius of the LF ladle furnace, m, H 钢液 is the height of molten steel, m.

[0037] Preferably, the Δm 耐材→炉渣 According to formula 10, we can get:

[0038] Δm 耐材→炉渣 =V2A 炉渣侧壁面 Δt Formula 10;

[0039] Where V2 is the dissolution rate of refractory in slag, kg·m -2 ·s -1 , A 炉渣侧壁面 is the area of ​​slag contacting the side wall of the refining furnace, m 2 .

[0040] Preferably, the A 炉渣侧壁面 According to formula 11, we can get:

[0041] A 炉渣侧壁面 =2πRH 炉渣 Formula 11;

[0042] Where R is the radius of the LF ladle furnace, m, H 炉渣 is the slag thickness, m.

[0043] Preferably, the carburizing mass Δm of the electrode to the carburizing zone of the molten steel within the time step is calculated according to Formula 12: 碳 ;

[0044]

[0045] Where I is the current through the electrode, kA; R 电极 is the electrode diameter, mm, Δt is the time step, S.

[0046] Beneficial effects: The LF refined steel liquid composition prediction method provided by the present invention needs to be combined with the relevant parameters and process of the LF refining furnace of the user's factory, and provides a customized working condition simulation method. This method can effectively optimize the smelting process of new steel grades without sufficient machine learning data, reduce the number of trial and error, improve production efficiency, reduce production costs, and improve the hit rate of steel liquid composition. This prediction method is based on the principles of metallurgical physical and chemical reactions, and comprehensively considers the interactions between elements and various phases based on the effective equilibrium reaction zone model (EERZ), which corresponds to the actual reaction process of LF refining and can accurately predict the composition of steel liquid in the LF refining process. By deeply understanding the internal reaction mechanism of each reaction zone, it goes beyond simple data logic and provides a more accurate prediction of steel liquid composition. Provide insights for understanding and controlling the smelting process. The present invention can adapt to sudden data fluctuations in production and provide effective predictions (this method is based on metallurgical principles and fits the actual reaction process. Even if data fluctuations occur, the actual reaction always conforms to the metallurgical reaction principle). The calculation process and method of the present invention correspond to the actual production process and can ensure the accuracy of the prediction under different process conditions. This adaptability makes the method always effective under dynamic production conditions, ensuring the stability of the continuous production process and the consistency of product quality. In addition, it can also help identify potential production problems and facilitate process adjustments in advance (the model can directly predict the physical and chemical reactions that will occur in the LF refining process before smelting, and the smelting process can be planned in advance), thereby reducing waste and improving efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 A schematic flow chart of a prediction model for the LF refined steel liquid composition prediction method provided by the present invention;

[0048] Figure 2 Input interface diagram for composition parameters;

[0049] Figure 3 Input interface diagram for process system;

[0050] Figure 4 This is the interface diagram after inputting the component parameters of Example 1;

[0051] Figure 5 This is the interface diagram after the process system is input in Example 1;

[0052] Figure 6 This is the interface diagram after inputting the component parameters of Example 2;

[0053] Figure 7 This is the interface diagram after entering the process system in Example 2. DETAILED DESCRIPTION

[0054] The present invention provides a method for predicting the composition of LF refined molten steel, comprising the following steps:

[0055] Step 1: Based on the effective equilibrium reaction zone model, the reactions occurring in the LF refining process are defined and divided in the form of reaction zones; the reaction zones include: the electrode carburizing zone into the molten steel, the alloy dissolving reaction zone in the molten steel, the inclusion floating zone, the refining slag dissolving in the slag reaction zone, the refractory and molten steel reaction zone, the refractory and slag reaction zone, the molten steel and slag reaction zone, the molten steel mixing zone, and the slag mixing zone;

[0056] Step 2: Determine the first molten steel composition and mass M according to the input molten steel composition and mass 钢液1 and the first inclusion composition and mass M 夹杂物1 , according to the first inclusion composition, mass M 夹杂物1 The mass of inclusions entering the inclusion floating area within the time step is calculated as Δm 夹杂物 and the mass M of inclusions entering the alloy dissolution reaction zone in the molten steel 夹杂物1 -Δm 夹杂物 ;

[0057] Calculate the carburizing mass Δm of the electrode into the carburizing zone of the molten steel within the time step according to the set power supply system 碳 , according to the carburizing mass Δm 碳 and the first molten steel composition and quality M 钢液1 Determine the composition and mass M of the second molten steel 钢液2 ;

[0058] According to the input alloy addition system and the second molten steel composition, quality M 钢液2 The composition and mass M of the second inclusion in the alloy dissolution reaction zone in the molten steel are calculated respectively. 夹杂物2 and the composition and quality M of the third molten steel 钢液3 ;

[0059] According to the refractory composition and dissolution rate, the mass of refractory participating in the reaction between refractory and molten steel in the time step is calculated respectively. 耐材→钢液and the mass of refractory material participating in the reaction between refractory material and slag Δm 耐材→炉渣 , and obtain the composition and mass M of the third inclusion in the reaction zone between the refractory and the molten steel 夹杂物3 The composition and quality M of the fourth molten steel in the reaction zone between the refractory and the molten steel 钢液4 ;

[0060] Determine the first slag composition and mass M according to the input slag composition and mass 炉渣1 , according to the first slag composition, mass M 炉渣 1. The refined slag feeding system and the inclusions floating in the inclusion floating area are set up to obtain the refined slag dissolved in the slag reaction area. The second slag composition and mass M 炉渣2 ; According to the mass of the refractory material participating in the reaction in the reaction zone between the refractory material and the slag Δm 耐材→炉渣 and the second slag composition and mass M 炉渣2 Get the third slag composition and mass M in the reaction zone between refractory and slag 炉渣3 ;

[0061] According to formula 1, the mass of molten steel participating in the reaction in the molten steel and slag reaction zone within the time step is calculated as Δm 钢液， According to formula 2, the mass of slag involved in the reaction in the reaction zone of molten steel and slag in the time step is calculated as Δm 炉渣 ;

[0062] Δm 钢液 =k 钢液 A 炉底 ρ 钢液 Δt Formula 1,

[0063] Δm 炉渣 =k 炉渣 A 炉底 ρ 炉渣 Δt Formula 2,

[0064] Among them, k 钢液 is the mass transfer coefficient of the steel liquid element, m·s -1 ;k 炉渣 is the mass transfer coefficient of the slag component, m·s -1 ; A 炉底 is the geometric area of ​​the steel liquid surface in the LF refining furnace, m 2 ρ 钢液 is the density of molten steel, kg·m -3 ρ 炉渣 is the slag density, kg·m -3 ; Δt is the time step, s;

[0065] In the time step, the mass of molten steel entering the molten steel mixing zone is Δm 新钢液 and M 钢液4 -Δm 钢液The mass of inclusions entering the mixing zone of molten steel is M 夹杂物2 、M 夹杂物3 and Δm 新夹杂物 ; The mass of slag entering the slag mixing zone is Δm 新炉渣 and M 炉渣3 -Δm 炉渣 ;

[0066] According to the reaction process of each reaction zone, a macro processing code in mac format is written to add alloy addition system, steel liquid composition and quality, refractory composition, slag composition and quality, power supply system, refined slag feeding system, Δm 碳 , Δm 夹杂物 、M 夹杂物1 -Δm 夹杂物 , Δm 耐材→钢液 , Δm 耐材→炉渣 , Δm 钢液 , Δm 炉渣 、M 钢液4 -Δm 钢液 and M 炉渣3 -Δm 炉渣 Perform macro processing coding and use FactSage to perform simulation calculations to obtain the phase composition and mass of each reaction zone after reaction;

[0067] Step 3: Repeat the operation of step 2 x times. When x△t is greater than or equal to the total LF refining time t 总 The calculation stops when the LF furnace smelting end point is output, and the molten steel composition and mass M 钢液 , the inclusion composition and quality M at the end of LF furnace smelting 夹杂物 The slag composition and quality M at the end of LF furnace smelting 炉渣 .

[0068] The LF refined steel liquid composition prediction method provided by the present invention includes step 1: based on the effective equilibrium reaction zone model, the reactions occurring in the LF refining process are defined and divided in the form of reaction zones; the reaction zones include: the electrode carburizing zone into the steel liquid, the alloy dissolving reaction zone in the steel liquid, the inclusion floating zone, the refined slag dissolving in the slag reaction zone, the refractory and steel liquid reaction zone, the refractory and slag reaction zone, the steel liquid and slag reaction zone, the steel liquid mixing zone, and the slag mixing zone. In the present invention, the basis for the division of the reaction zones is as follows: (1) The electrode carburizing zone into the steel liquid: during the LF heating process, the electrode will be lost and enter the steel liquid, resulting in an increase in the carbon content of the steel liquid; (2) The alloy dissolving reaction zone in the steel liquid: during the smelting process, it is necessary to add a deoxidizing alloy to the LF ladle furnace to deoxidize the steel liquid, and add the alloy to make the steel liquid reach the target composition; the newly added alloy in this area dissolves rapidly, thereby changing the composition of the steel liquid; the time for adding the alloy refers to the alloy adding system; (3) The inclusion floating zone: the inclusions generated during the smelting process, in Under the action of bottom blowing stirring and the buoyancy of the inclusions themselves, they will float up from the molten steel into the slag; the inclusions dispersed in the steel in this area float up at a constant rate; (4) Refined slag dissolves in the slag reaction zone: During the smelting process, refined slag needs to be added to the LF ladle furnace for slag making; the newly added refined slag in this area gradually dissolves due to heat, thereby changing the composition of the slag; the timing of adding refined slag refers to the refined slag feeding system; (5) Refractory and molten steel reaction zone: In actual production, the molten steel will wash the refractory, causing the refractory to slowly dissolve into the molten steel. Thus, it affects the composition of molten steel; in this area, the refractory material dissolves into the molten steel at a constant rate; (6) Refractory and slag reaction zone: In actual production, the slag washes and corrodes the refractory material, causing the refractory material to gradually dissolve into the slag, thereby affecting the composition of the slag; in this area, the refractory material dissolves into the slag at a constant rate; (7) Molten steel and slag reaction zone: LF refining mainly desulfurizes through the interface reaction between slag and molten steel. Because slag and molten steel are not miscible and its density is smaller than that of molten steel, it floats on the upper layer of the molten steel surface. The reaction between slag and molten steel mainly occurs at the slag-steel interface; (8 ) Molten steel mixing zone: Since the composition of molten steel and slag changes after the reaction, the composition of molten steel and slag on both sides of the interface after the reaction is different from the composition of the original phase that does not participate in the interface reaction. Therefore, diffusion mixing will occur between the reacted molten steel and the unreacted molten steel, and between the reacted slag and the unreacted slag. In actual production, the bottom blowing gas in the LF ladle furnace is used to stir the molten steel in order to make the composition of the molten steel uniform. This mixing zone considers that at the end of a time step, the molten steel generated in each reaction zone is mixed and updated once, which is used as the initial value for the next time step calculation. (9) Slag mixing zone: Similar to the molten steel mixing zone, it is also to ensure that the composition of the slag after the reaction is uniform. This mixing zone considers that at the end of a time step, the slag generated in each reaction zone is mixed and updated once, which is used as the initial value for the next time step calculation.

[0069] The LF refined steel liquid composition prediction method provided by the present invention comprises step 2: determining the first steel liquid composition, quality M according to the input steel liquid composition and quality 钢液1 and the first inclusion composition and mass M 夹杂物1 , according to the first inclusion composition, mass M 夹杂物1 Get the mass of inclusions entering the inclusion floating area within the time step Δm 夹杂物 and the mass M of inclusions entering the alloy dissolution reaction zone in the molten steel 夹杂物1 -Δm 夹杂物 In the present invention, the Δm 夹杂物 The mass of inclusions to be removed is preferably calculated according to Formula 6:

[0070] Δm 夹杂物 =r fl ×M 夹杂物1 Formula 6;

[0071] Among them, r fl is the inclusion removal rate.

[0072] In the present invention, the r fl Preferably, it is calculated according to Formula 7:

[0073] r fl =4.2×10 -4 ε 0.2 Formula 7;

[0074] Where ε is the stirring energy, W·t -1 ; Preferably calculated according to formula 5:

[0075]

[0076] Where n is the molar gas flow rate, mol·s -1 ; R is the ideal gas constant, J·mol -1 ·K -1 ; T is the temperature of molten steel, K; M 钢液4 The unit is t; P t is the total gas pressure at the bottom of the ladle, Pa; P0 is the gas pressure on the melt surface, Pa. In the present invention, the stirring energy ε is preferably determined by the bottom blowing flow rate.

[0077] The present invention calculates the carburizing mass Δm of the electrode to the carburizing zone of the molten steel within the time step according to the power supply system set 碳 , according to the carburizing mass Δm 碳 and the first molten steel composition and quality M 钢液1 Determine the composition and mass M of the second molten steel 钢液2 In the present invention, the Δm 碳Preferably, it is calculated according to formula 12:

[0078]

[0079] Where I is the current through the electrode, kA; R 电极 is the electrode diameter, mm, Δt is the time step, S.

[0080] The present invention is based on the input alloy addition system and the second molten steel composition, quality M 钢液2 The composition and mass M of the second inclusion in the alloy dissolution reaction zone in the molten steel are obtained respectively. 夹杂物2 and the composition and quality M of the third molten steel 钢液3 .

[0081] The present invention calculates the mass Δm of the refractory material participating in the reaction between the refractory material and the molten steel in the time step according to the refractory material composition and the dissolution rate. 耐材→钢液 and the mass of refractory material participating in the reaction between refractory material and slag Δm 耐材→炉渣 , and obtain the composition and mass M of the third inclusion in the reaction zone between the refractory and the molten steel 夹杂物3 The composition and mass M of the fourth molten steel in the reaction zone between the refractory and the molten steel 钢液4 In the present invention, the Δm 耐材→钢液 Preferably, it is calculated according to formula 8:

[0082] Δm 耐材→钢液 =V1A 钢液侧壁面 Δt Formula 8;

[0083] Where V1 is the rate at which the refractory material dissolves in the molten steel (kg·m) -2 ·s -1 ; A 钢液侧壁面 is the area of ​​the molten steel contacting the side wall of the refining furnace, m 2 In the present invention, V1 is preferably 0.0005 kg·m -2 ·s -1 .

[0084] In the present invention, the A 钢液侧壁面 Preferably, it is calculated according to formula 9:

[0085] A 钢液侧壁面 =2πRH 钢液 Formula 9;

[0086] Where R is the radius of the LF ladle furnace, m; H 钢液 is the height of molten steel, m.

[0087] In the present invention, the Δm 耐材→炉渣 According to formula 10, we can get:

[0088] Δm 耐材→炉渣=V2A 炉渣侧壁面 Δt Formula 10:

[0089] Where V2 is the dissolution rate of the refractory in the slag kg·m -2 ·s -1 , A 炉渣侧壁面 The area of ​​slag contacting the side wall of the refining furnace. In the present invention, V2 is preferably 0.001 kg·m -2 ·s -1 .

[0090] In the present invention, the A 炉渣侧壁面 According to formula 11, we can get:

[0091] A 炉渣侧壁面 =2πRH 炉渣 Formula 11:

[0092] Where R is the radius of the LF ladle furnace, m; H 炉渣 is the slag thickness, m.

[0093] The present invention determines the first slag composition and mass M according to the input slag composition and mass 炉渣1 , according to the first slag composition, mass M 炉渣1 , the set refined slag feeding system and the inclusions floating in the inclusion floating area obtain the refined slag dissolved in the slag reaction area, the second slag composition, mass M 炉渣2 ; According to the mass of the refractory material participating in the reaction in the reaction zone between the refractory material and the slag Δm 耐材→炉渣 and the second slag composition and mass M 炉渣2 Get the third slag composition and mass M in the reaction zone between refractory and slag 炉渣3 .

[0094] The present invention calculates the mass Δm of the molten steel entering the reaction zone of the molten steel and slag and participating in the reaction within the time step according to Formula 1: 钢液 , according to formula 2, calculate the mass Δm of slag that enters the reaction zone between molten steel and slag and participates in the reaction within the time step 炉渣 .

[0095] Δm 钢液 =k 钢液 A 炉底 ρ 钢液 Δt Formula 1,

[0096] Δm 炉渣 =k 炉渣 A 炉底 ρ 炉渣 Δt Formula 2,

[0097] Among them, k 钢液 is the mass transfer coefficient of the steel liquid element, m·s -1 ;k炉渣 is the mass transfer coefficient of the slag component, m·s -1 ; A 炉底 is the geometric area of ​​the steel liquid surface in the LF refining furnace, m 2 ρ 钢液 is the density of molten steel, kg·m -3 ρ 炉渣 is the slag density, kg·m -3 ; Δt is the time step, s.

[0098] In the present invention, the time step is the time length of the simulation cycle calculation, and the time step is artificially divided according to the total time length of LF refining; the maximum value of the time step Δt is preferably 1 / 10 of the total time length. In the present invention, the Δt is preferably 1 min.

[0099] The present invention preferably calculates the mass transfer coefficient of steel according to Formula 3:

[0100] k 钢液 =4×10 -6 ε 1.4 H 钢液 Formula 3;

[0101] Where ε is the stirring energy, W·t -1 ;H 钢液 is the height of molten steel in LF refining furnace, m.

[0102] The present invention preferably calculates the stirring energy according to Formula 5:

[0103]

[0104] Where n is the molar gas flow rate, mol·s -1 ; R is the ideal gas constant, J·mol -1 ·K -1 ; T is the temperature of molten steel, K; M 钢液4 The unit is t; P t is the total gas pressure at the bottom of the ladle, Pa; P0 is the gas pressure on the melt surface, Pa.

[0105] The present invention preferably calculates the mass transfer coefficient of the slag according to Formula 4:

[0106]

[0107] In the present invention, A 炉底 Preferably, it is calculated according to formula 13:

[0108] A 炉底 =πR 2 Formula 13;

[0109] Where R is the radius of the LF ladle furnace.

[0110] In the time step, the mass of molten steel entering the molten steel mixing zone is Δm 新钢液 and M 钢液4 -Δm 钢液 , the mass of inclusions entering the mixing zone of molten steel is M 夹杂物2 、M 夹杂物3 and Δm 新夹杂物 ; The mass of slag entering the slag mixing zone is Δm 新炉渣 and M 炉渣3 -Δm 炉渣 ;

[0111] The present invention compiles a macro processing code in mac format according to the reaction logic of each reaction zone, and integrates the alloy addition system, steel liquid composition and quality, refractory composition, slag composition and quality, power supply system, refined slag feeding system, Δm 夹杂物 、M 夹杂物1 -Δm 夹杂物 , Δm 耐材→钢液 , Δm 耐材→炉渣 , Δm 钢液 , Δm 炉渣 、M 钢液4 -Δm 钢液 and M 炉渣3 -Δm 炉渣 Macro processing coding is performed, and FactSage is used for simulation calculation to obtain the phase composition and mass after the reaction in each reaction zone.

[0112] The method for predicting the composition of LF refined steel liquid provided by the present invention comprises step 3: repeating the operation of step 2 x times, when xΔt is greater than or equal to the total LF refining time t 总 The calculation stops when the LF refining smelting end point is output, and the steel liquid composition and quality M 钢液 , the inclusion composition and quality M at the end of LF furnace smelting 夹杂物 The slag composition and quality M at the end of LF furnace smelting 炉渣 .

[0113] The flow chart of the prediction model of the LF refined steel liquid composition prediction method provided by the present invention is as follows: Figure 1 Specifically, the parameters related to the composition and quality of molten steel, slag composition and quality, alloy addition system, power supply system, refining slag feeding system and refractory composition, time step, and total LF refining time are first input into the prediction model, and the model updates the composition and quality of molten steel (M 钢液1 ), update the composition and quality of inclusions (M 夹杂物1 ), update slag composition and quality (M 炉渣1 ); In the carburizing zone of the electrode into the molten steel, the electrode itself will be lost during the heating process and enter the molten steel in the form of carburization. The carburization amount is Δm 碳, these carbon and molten steel (M 钢液1 ) to perform a thermodynamic equilibrium calculation, and update the composition and mass of the molten steel when the calculation is completed (M 钢液2 ); in the inclusion floating reaction zone, considering some inclusions (Δm 夹杂物 ) floats up into the slag (M 炉渣1 ) in the alloy dissolving reaction zone in the molten steel; alloy, molten steel (M 钢液2 ), residual inclusions (M 夹杂物1 -Δm 夹杂物 ) Thermodynamic equilibrium calculation of the three, when the refined slag is dissolved in the slag reaction zone, the refined slag, slag (M 炉渣1 ), inclusions that float up into the slag (Δm 夹杂物 ) Thermodynamic equilibrium calculation of the three; when the equilibrium calculation of alloy dissolution reaction zone in molten steel and refined slag dissolution in slag reaction zone is completed, update the inclusion composition and mass (M 夹杂物2 ), liquid steel composition and quality (M 钢液3 ), slag composition and quality (M 炉渣2 ) In the reaction zone between refractory and molten steel, considering the dissolution reaction of refractory in molten steel, the mass of refractory entering molten steel is Δm 耐材→钢液 , and then the reaction zone refractory (Δm 耐材→钢液 ) and molten steel (M 钢液3 ) to calculate the thermodynamic equilibrium and update the composition and quality of the molten steel (M 钢液4 ) and inclusion composition and quality (M 夹杂物3 ) In the reaction zone between refractory and slag, the dissolution reaction of refractory in slag is taken into account, and the mass of refractory entering slag is Δm 耐材→炉渣 Then the reaction zone refractory (Δm 耐材→炉渣 ) and slag (M 炉渣2 ) and update the slag composition and mass (M 炉渣3 ); In the reaction zone between molten steel and slag, only part of the molten steel (Δm 钢液 ) and part of the slag (Δm 炉渣 ) reaction occurs, so only the molten steel (Δm 钢液 ) and slag (Δm 炉渣 ) to perform thermodynamic equilibrium calculations, and then update the composition and mass of the molten steel after the reaction (Δm 新钢液 ), slag composition and quality (Δm 新炉渣 ), inclusion composition and mass (Δm 新夹杂物 ); In the steel liquid mixing zone, the steel liquid that does not participate in the slag reaction (M 钢液4 -Δm 钢液 ), inclusions generated in the alloy dissolution reaction zone in the molten steel (M 夹杂物2 ), inclusions generated in the reaction zone between refractory and molten steel (M夹杂物3 ), molten steel after slag reaction (Δm 新钢液 ) and the inclusions generated by the reaction of slag (Δm 新夹杂物 ) Mix the five elements and then update the composition and quality of the molten steel (M 钢液5 ), inclusion composition and quality (M 夹杂物4 ), determine whether the total running time t satisfies t<t 总 If it is less than the total time, continue to calculate, based on the composition and mass of the molten steel at this time (M 钢液5 ), inclusion composition and quality (M 夹杂物4 ) is used as the input value for the next cycle calculation, and so on, until t≥t is satisfied. 总 Output the final molten steel composition and quality (M 钢液5 ), inclusion composition and quality (M 夹杂物4 In the slag mixing zone, the slag that does not participate in the slag-metal reaction (M 炉渣3 -Δm 炉渣 ) and steel slag to form slag (Δm 新炉渣 ) and then update the slag composition and quality (M 炉渣4 ), determine whether the total running time t satisfies t<t 总 If it is less than the total time, the calculation continues, and the slag composition and mass at this time are used as the input value for the next cycle calculation, and so on, until t≥t 总 Output the final slag composition and quality (M 炉渣4 ).

[0114] Figure 2 and Figure 3 They are the input interface diagrams of composition parameters and process system respectively.

[0115] The present invention uses an effective equilibrium reaction zone model to define and divide each effective reaction zone in the LF refining process; based on the divided reaction zones, its related parameters, such as reaction amount, inclusion floating rate, refractory dissolution rate, etc., are determined; and by using FactSage thermodynamic calculation software and running macro processing code, the composition of molten steel in the LF refining process can be predicted. Since the prediction method provided by the present invention does not require machine learning data for training, process design and optimization can be carried out under limited data support, reducing the number of trial and error times, improving production efficiency, and will help reduce production costs and improve the quality of molten steel. The composition prediction provided by the present invention is based on the principle of multiphase physical and chemical reactions, comprehensively considers the interaction between the various phases in the LF refining process, effectively corresponds to the actual reaction process of LF refining, and can accurately predict the composition changes of LF refined molten steel. This simulation method that deeply understands the internal mechanism of the reaction can provide a more accurate prediction of the composition of molten steel. The prediction method of the present invention can adapt to sudden data fluctuations in actual production, ensure the accuracy of the prediction, and is always effective under dynamic and unpredictable production conditions, ensuring the stability of the continuous production process and the consistency of product quality.

[0116] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0117] Example 1

[0118] Taking the production process of smelting 45# steel in a 220t LF refining furnace of a steel plant as an example, the composition of LF refined steel liquid is predicted. The steps are as follows:

[0119] Collect relevant parameters, including: the size of the plant's 220t LF refining furnace, target steel composition, initial steel liquid composition and weight, initial slag composition and weight, power supply system, refining slag feeding system, alloy addition system, furnace lining refractory composition, steel liquid temperature, gas flow rate, total gas pressure at the bottom of the ladle and gas pressure on the surface of the steel liquid, and total LF refining time. Enter these parameters in the composition parameter input interface and process system input interface diagram. The specific parameters to be entered are as follows: Figure 4 and Figure 5 shown.

[0120] After calculation, the composition and quality of the molten steel (M 钢液1 ), update the composition and quality of inclusions (M 夹杂物1 ), update slag composition and quality (M 炉渣1 ); In the carburizing zone of the electrode into the molten steel, the electrode itself will be lost during the heating process and enter the molten steel in the form of carburization. The carburization amount is Δm 碳 , these carbon and steel liquid (M 钢液1 ) to perform a thermodynamic equilibrium calculation, and update the composition and mass of the molten steel when the calculation is completed (M钢液2 ); in the inclusion floating reaction zone, considering some inclusions (Δm 夹杂物 ) floats up into the slag (M 炉渣1 ) in the alloy dissolving reaction zone in the molten steel; alloy, molten steel (M 钢液2 ), residual inclusions (M 夹杂物1 -Δm 夹杂物 ) Thermodynamic equilibrium calculation of the three, when the refined slag is dissolved in the slag reaction zone, the refined slag, slag (M 炉渣1 ), inclusions that float up into the slag (Δm 夹杂物 ) Thermodynamic equilibrium calculation of the three; when the equilibrium calculation of alloy dissolution reaction zone in molten steel and refined slag dissolution in slag reaction zone is completed, update the inclusion composition and mass (M 夹杂物2 ), liquid steel composition and quality (M 钢液3 ), slag composition and quality (M 炉渣2 ) In the reaction zone between refractory and molten steel, considering the dissolution reaction of refractory in molten steel, the mass of refractory entering molten steel is Δm 耐材→钢液 , and then the reaction zone refractory (Δm 耐材→钢液 ) and molten steel (M 钢液3 ) to calculate the thermodynamic equilibrium and update the composition and quality of the molten steel (M 钢液4 ) and inclusion composition and quality (M 夹杂物3 ) In the reaction zone between refractory and slag, the dissolution reaction of refractory in slag is taken into account, and the mass of refractory entering slag is Δm 耐材→炉渣, Then the reaction zone refractory (Δm 耐材→炉渣 ) and slag (M 炉渣2 ) and update the slag composition and mass (M 炉渣3 ); In the reaction zone between molten steel and slag, only part of the molten steel (Δm 钢液 ) and part of the slag (Δm 炉渣 ) reaction occurs, so only the molten steel (Δm 钢液 ) and slag (Δm 炉渣 ) to perform thermodynamic equilibrium calculations, and then update the composition and mass of the molten steel after the reaction (Δm 新钢液 ), slag composition and quality (Δm 新炉渣 ), inclusion composition and mass (Δm 新夹杂物 ); In the steel liquid mixing zone, the steel liquid that does not participate in the slag reaction (M 钢液4 -Δm 钢液 ), inclusions generated in the alloy dissolution reaction zone in the molten steel (M 夹杂物2 ), inclusions generated in the reaction zone between refractory and molten steel (M 夹杂物3 ), molten steel after slag reaction (Δm 新钢液 ) and the inclusions generated by the reaction of slag (Δm新夹杂物 ) Mix the five elements and then update the composition and quality of the molten steel (M 钢液5 ), inclusion composition and quality (M 夹杂物4 ), determine whether the total running time t satisfies t<t 总 If it is less than the total time, continue to calculate, based on the composition and mass of the molten steel at this time (M 钢液5 ), inclusion composition and quality (M 夹杂物4 ) is used as the input value for the next cycle calculation, and so on, until t≥t is satisfied. 总 Output the final molten steel composition and quality (M 钢液5 ), inclusion composition and quality (M 夹杂物4 In the slag mixing zone, the slag that does not participate in the slag-metal reaction (M 炉渣3 -Δm 炉渣 ) and steel slag to form slag (Δm 新炉渣 ) and then update the slag composition and quality (M 炉渣4 ), after repeating the above process 30 times, the total running time is 30 minutes, which is equal to t 总 (30min), output the final composition and quality of molten steel (M 钢液5 ). The steel liquid composition predicted by this model is highly consistent with the actual production data, as shown in Table 1.

[0121] Table 1 Comparison of predicted composition of molten steel in Example 1

[0122] Element Actual value Predicted value error Fe 98.6008％ 98.6040％ 0.0032％ C 0.4458％ 0.4423％ -0.0035％ Si 0.2180％ 0.2194％ 0.0014％ Mn 0.6790％ 0.6781％ -0.0009％ P 0.0172％ 0.0171％ -0.0001％ S 0.0027％ 0.0023％ -0.0004％ O 0.0083％ 0.0095％ 0.0012％ Al 0.0261％ 0.0255％ -0.0006％ Ni 0.0021％ 0.0018％ -0.0003％

[0123] Example 2

[0124] Taking the production process of industrial pure iron smelting in a steel plant with a double 120t LF refining furnace as an example, the composition of LF refined steel liquid is predicted. The steps are as follows:

[0125] Collect relevant parameters, including: the size of the plant's 120t LF refining furnace, target steel composition, initial steel liquid composition and weight, initial slag composition and weight, power supply system, refining slag feeding system, alloy addition system, lining refractory composition, steel liquid temperature, gas flow rate, total gas pressure at the bottom of the ladle and gas pressure on the surface of the steel liquid, and total LF refining time. Enter these parameters in the composition parameter input interface and process system input interface diagram. The specific parameters to be entered are as follows: Figure 6 and Figure 7 shown.

[0126] After calculation, the composition and quality of the molten steel (M 钢液1 ), update the composition and quality of inclusions (M 夹杂物1 ), update slag composition and quality (M 炉渣1); In the carburizing zone of the electrode to the molten steel, the electrode itself will be lost during the heating process and enter the molten steel in the form of carburization. The carburization amount is Δm 碳 , these carbon and steel liquid (M 钢液1 ) to perform a thermodynamic equilibrium calculation, and update the composition and mass of the molten steel when the calculation is completed (M 钢液2 ); in the inclusion floating reaction zone, considering some inclusions (Δm 夹杂物 ) floats up into the slag (M 炉渣1 ) in the alloy dissolving reaction zone in the molten steel; alloy, molten steel (M 钢液2 ), residual inclusions (M 夹杂物1 -Δm 夹杂物 ) Thermodynamic equilibrium calculation of the three, when the refined slag is dissolved in the slag reaction zone, the refined slag, slag (M 炉渣1 ), inclusions that float up into the slag (Δm 夹杂物 ) Thermodynamic equilibrium calculation of the three; when the equilibrium calculation of alloy dissolution reaction zone in molten steel and refined slag dissolution in slag reaction zone is completed, update the inclusion composition and mass (M 夹杂物2 ), liquid steel composition and quality (M 钢液3 ), slag composition and quality (M 炉渣2 ) In the reaction zone between refractory and molten steel, considering the dissolution reaction of refractory in molten steel, the mass of refractory entering molten steel is Δm 耐材→钢液 , and then the reaction zone refractory (Δm 耐材→钢液 ) and molten steel (M 钢液3 ) to calculate the thermodynamic equilibrium and update the composition and quality of the molten steel (M 钢液4 ) and inclusion composition and quality (M 夹杂物3 ) In the reaction zone between refractory and slag, the dissolution reaction of refractory in slag is taken into account, and the mass of refractory entering slag is Δm 耐材→炉渣 , and then the reaction zone refractory (Δm 耐材→炉渣 ) and slag (M 炉渣2 ) and update the slag composition and mass (M 炉渣3 ); In the reaction zone between molten steel and slag, only part of the molten steel (Δm 钢液 ) and part of the slag (Δm 炉渣 ) reaction occurs, so only the molten steel (Δm 钢液 ) and slag (Δm 炉渣 ) to perform thermodynamic equilibrium calculations, and then update the composition and mass of the molten steel after the reaction (Δm 新钢液 ), slag composition and quality (Δm 新炉渣 ), inclusion composition and mass (Δm 新夹杂物 ); In the steel liquid mixing zone, the steel liquid that does not participate in the slag reaction (M 钢液4 -Δm 钢液), inclusions generated in the alloy dissolution reaction zone in the molten steel (M 夹杂物2 ), inclusions generated in the reaction zone between refractory and molten steel (M 夹杂物3 ), molten steel after slag reaction (Δm 新钢液 ) and the inclusions generated by the reaction of slag (Δm 新夹杂物 ) Mix the five elements and then update the composition and quality of the molten steel (M 钢液5 ), inclusion composition and quality (M 夹杂物4 ), determine whether the total running time t satisfies t<t 总 If it is less than the total time, continue to calculate, based on the composition and mass of the molten steel at this time (M 钢液5 ), inclusion composition and quality (M 夹杂物4 ) is used as the input value for the next cycle calculation, and so on, until t≥t is satisfied. 总 Output the final molten steel composition and quality (M 钢液5 ), inclusion composition and quality (M 夹杂物4 In the slag mixing zone, the slag that does not participate in the slag-metal reaction (M 炉渣3 -Δm 炉渣 ) and steel slag to form slag (Δm 新炉渣 ) and then update the slag composition and quality (M 炉渣4 ), after repeating the above process 125 times, the total running time is 125min, which is equal to t 总 (125min), output the final composition and quality of molten steel (M 钢液5 ). The steel liquid composition predicted by this model is highly consistent with the actual production data, as shown in Table 2.

[0127] Table 2 Comparison of predicted composition of molten steel in Example 2

[0128] Element Actual value Predicted value error Fe 99.8406％ 99.8399％ -0.0007％ C 0.0585％ 0.0572％ -0.0013％ Si 0.0560％ 0.0568％ 0.0008％ Mn 0.0230％ 0.0227％ -0.0003％ P 0.0019％ 0.0023％ 0.0004％ S 0.0010％ 0.0014％ 0.0004％ O 0.0040％ 0.0035％ -0.0005％ Al 0.0150％ 0.0162％ 0.0012％

[0129] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for predicting the composition of LF refined molten steel, characterized in that: The following steps are involved: Step 1: Based on the effective equilibrium reaction zone model, the reactions occurring in the LF refining process are defined and divided in the form of reaction zones; the reaction zones include: the electrode carburizing zone into the molten steel, the alloy dissolving reaction zone in the molten steel, the inclusion floating zone, the refining slag dissolving in the slag reaction zone, the refractory and molten steel reaction zone, the refractory and slag reaction zone, the molten steel and slag reaction zone, the molten steel mixing zone, and the slag mixing zone; Step 2: Determine the first molten steel composition and mass M according to the input molten steel composition and mass 钢液1 and the first inclusion composition and mass M 夹杂物1 , according to the first inclusion composition, mass M 夹杂物1 Get the mass of inclusions entering the inclusion floating area within the time step Δm 夹杂物 and the mass M of inclusions entering the alloy dissolution reaction zone in the molten steel 夹杂物1 -Δm 夹杂物 ; Calculate the carburizing mass Δm of the electrode into the carburizing zone of the molten steel within the time step according to the set power supply system 碳 , according to the carburizing mass Δm 碳 and the first molten steel composition and quality M 钢液1 Determine the composition and mass M of the second molten steel 钢液2 ; According to the input alloy addition system and the second molten steel composition, quality M 钢液2 The composition and mass M of the second inclusion in the alloy dissolution reaction zone in the molten steel are obtained respectively. 夹杂物2 and the composition and quality M of the third molten steel 钢液3 ; According to the refractory composition and dissolution rate, the mass of refractory participating in the reaction between refractory and molten steel in the time step is calculated respectively. 耐材→钢液 and the mass of refractory material participating in the reaction between refractory material and slag Δm 耐材→炉渣 , and obtain the composition and mass M of the third inclusion in the reaction zone between the refractory and the molten steel 夹杂物3 The composition and mass M of the fourth molten steel in the reaction zone between the refractory and the molten steel 钢液4 ; Determine the first slag composition and mass M according to the input slag composition and mass 炉渣1 , according to the first slag composition, mass M 炉渣1 , the set refined slag feeding system and the inclusions floating in the inclusion floating area obtain the refined slag dissolved in the slag reaction area, the second slag composition, mass M 炉渣2 ; According to the mass of the refractory material participating in the reaction in the reaction zone between the refractory material and the slag Δm 耐材→炉渣 and the second slag composition and mass M 炉渣2 Get the third slag composition and mass M in the reaction zone between refractory and slag 炉渣3 ; According to formula 1, the mass of molten steel participating in the reaction in the molten steel and slag reaction zone within the time step is calculated as Δm 钢液 , according to formula 2, calculate the mass Δm of slag involved in the reaction of molten steel and slag reaction zone within the time step 炉渣 ; Δm 钢液 = k 钢液 A 炉底 ρ 钢液 Δt Formula 1 Δm 炉渣 = k 炉渣 A 炉底 ρ 炉渣 Δt Formula 2 Among them, k 钢液 is the mass transfer coefficient of the steel liquid element, m·s -1 ;k 炉渣 is the mass transfer coefficient of the slag component, m·s -1 ; A 炉底 is the geometric area of ​​the steel liquid surface in the LF refining furnace, m 2 ρ 钢液 is the density of molten steel, kg·m -3 ρ 炉渣 is the slag density, kg·m -3 ; Δt is the time step, s; In the time step, the mass of molten steel entering the molten steel mixing zone is Δm 新钢液 and M 钢液4 -Δm 钢液 , the mass of inclusions entering the mixing zone of molten steel is M 夹杂物2 、M 夹杂物3 and Δm 新夹杂物 ; The mass of slag entering the slag mixing zone is Δm 新炉渣 and M 炉渣3 -Δm 炉渣 ; According to the reaction process of each reaction zone, a macro processing code in mac format is written to add alloy addition system, steel liquid composition and quality, refractory composition, slag composition and quality, power supply system, refined slag feeding system, Δm 碳 , Δm 夹杂物 、M 夹杂物1 -Δm 夹杂物 , Δm 耐材→钢液 , Δm 耐材→炉渣 , Δm 钢液 , Δm 炉渣 、M 钢液4 -Δm 钢液 and M 炉渣3 -Δm 炉渣 Perform macro processing coding and use FactSage to perform simulation calculations to obtain the phase composition and mass of each reaction zone after reaction; Step 3: Repeat the operation of step 2 x times. When x△t is greater than or equal to the total LF refining time t 总 The calculation stops when the LF furnace smelting end point is output, and the molten steel composition and mass M 钢液 , the inclusion composition and quality M at the end of LF furnace smelting 夹杂物 The slag composition and quality M at the end of LF furnace smelting 炉渣 .

2. The method for predicting the composition of LF refined steel liquid according to claim 1, characterized in that: The mass transfer coefficient of steel is calculated according to Formula 3, and the mass transfer coefficient of slag components is calculated according to Formula 4: k 钢液 = 4×10 -6 ε 1.4 H 钢液 Equation 3; Where ε is the stirring energy, W·t -1 ;H 钢液 is the height of molten steel in LF refining furnace, m.

3. The method for predicting the composition of LF refined steel liquid according to claim 2, characterized in that: The stirring energy is calculated according to formula 5: Where n is the molar gas flow rate, mol·s -1 ; R is the ideal gas constant, J·mol -1 ·K -1 ; T is temperature, K; M 钢液4 The unit is t; P t is the total gas pressure at the bottom of the ladle, Pa; P0 is the gas pressure on the melt surface, Pa.

4. The method for predicting the composition of LF refined steel liquid according to claim 1, characterized in that: The Δm 夹杂物 According to formula 6, we can get: Δm 夹杂物 =r fl ×M 夹杂物1 Formula 6; Among them, r fl is the inclusion removal rate.

5. The method for predicting the composition of LF refined steel liquid according to claim 4, characterized in that: The r fl According to formula 7, we can get: r fl = 4.2×10 -4 ε 0.2 Formula 7.

6. The method for predicting the composition of LF refined steel liquid according to claim 1, characterized in that: The Δm 耐材→钢液 According to formula 8, we can get: Δm 耐材→钢液 =V1A 钢液侧壁面 Δt Formula 8; Where V1 is the dissolution rate of the refractory in the molten steel, kg·m -2 ·s -1 , A 钢液侧壁面 is the area of ​​the molten steel contacting the side wall of the refining furnace, m 2 .

7. The method for predicting the composition of LF refined steel liquid according to claim 6, characterized in that: The A 钢液侧壁面 According to formula 9, we can get: A 钢液侧壁面 =2πRH 钢液 Formula 9; Where R is the radius of the LF ladle furnace, m, H 钢液 is the height of molten steel, m.

8. The method for predicting the composition of LF refined steel liquid according to claim 1, characterized in that: The Δm 耐材→炉渣 According to formula 10, we can get: Δm 耐材→炉渣 =V2A 炉渣侧壁面 Δt Formula 10; Where V2 is the dissolution rate of refractory in slag, kg·m -2 ·s -1 , A 炉渣侧壁面 is the area of ​​slag contacting the side wall of the refining furnace, m 2 .

9. The method for predicting the composition of LF refined steel liquid according to claim 8, characterized in that: The A 炉渣侧壁面 According to formula 11, we can get: A 炉渣侧壁面 =2πRH 炉渣 Formula 11; Where R is the radius of the LF ladle furnace, m, H 炉渣 is the slag thickness, m.

10. The method for predicting the composition of LF refined steel liquid according to claim 1, characterized in that: According to formula 12, the carburization mass Δm of the electrode into the carburized zone of the molten steel within the time step is calculated 碳 ; Where I is the current through the electrode, kA; R 电极 is the electrode diameter, mm, and Δt is the time step, s.

Images