Full-process intelligent refining system applied to LF refining furnace

Abstract

The invention provides a full-process intelligent refining system applied to an LF refining furnace, and relates to the field of ferrous metallurgy. The full-process intelligent refining system comprises the steps that a slagging control module calculates the adding amount of a slagging constituent; the temperature prediction module predicts and controls the temperature of the molten steel in real time; the argon blowing control module establishes a relation model between the molten steel exposed area and the bottom blowing argon flow; the wire feeding prediction module calculates the feeding quantity of the aluminum wire and the calcium wire; the alloy calculation module automatically controls the alloy adding amount; the machine auxiliary module is used for collecting data and sampling and sticking slag; the main control module is used for controlling system operation; and server data storage and interaction. According to the method, a statistical method, mechanism calculation and other technologies are used, the mechanism model of each refining process is established, the refining process is predicted and automatically controlled, the alloy component hit rate and the temperature standard-reaching rate are effectively increased, and meanwhile alloy consumption and power consumption are reduced.

Description

Technical Field

[0001] The present application relates to the technical field of iron and steel metallurgy, and in particular to a full-process intelligent refining system applied to an LF refining furnace. Background Art

[0002] Refining process plays a vital role in steel smelting. Through refining, non-metallic inclusions and gas inclusions in steel can be effectively removed, and the content of harmful elements such as oxygen, sulfur and nitrogen in steel can be reduced, thereby improving the quality and reliability of steel. In addition, the refining process can also improve the purity of molten steel, reduce the generation of slag, reduce production costs and improve production efficiency. Therefore, the refining process is an indispensable part of the steel smelting process. The refining process usually includes two stages: primary refining and secondary refining. Primary refining is mainly carried out in blast furnaces and converters. The blast furnace is used to reduce iron ore into liquid pig iron, while the converter removes impurities in pig iron, such as carbon, silicon, phosphorus and other elements, through oxidation reactions, and further adjusts the composition of steel. Secondary refining is also called secondary refining, which is usually carried out in equipment such as ladle refining furnaces and vacuum degassing furnaces. The main task of this stage is to further remove harmful elements such as oxygen, sulfur and nitrogen in steel and improve the purity and mechanical properties of steel. LF refining, or outside-furnace refining, is an important secondary refining process in steel production. It uses white slag to desulfurize and deoxidize molten steel to produce ultra-low sulfur steel and low-oxygen steel. Its main purpose is to further treat the primary molten steel to meet the requirements of the continuous casting process and improve the quality and stability of the molten steel.

[0003] The traditional LF refining process has many problems, such as high labor intensity, high risk factor, chaotic smelting process and standards, large control fluctuations, high material and energy consumption, high process cost, and poor product quality stability.

[0004] The existing LF refining mainly relies on manual subjective operation. There is a lack of relatively unified standards for slag-to-material ratio, alloy ratio, argon blowing intensity, temperature control, wire feeding length and other operations. Most of the operations are manually controlled by humans in front of the furnace or in the operation room. The degree of automation and informatization is low, which can easily lead to problems such as increased power consumption, material waste, and alloy composition exceeding the required steel grade. In addition, the degree of intelligence and automation is low, and the labor intensity is high, which can easily lead to low control accuracy, long processing cycle, and waste of energy, which is not conducive to the stability of steel quality and cost reduction.

[0005] At present, most LF process control and decision-making models are single-function or partial-function combined models, and overall integrated applications are rare. Since the LF refining process involves multivariable, nonlinear, strong coupling and other characteristics, and the working environment is harsh and the random interference is strong, this makes the control model prediction distorted, the process standardization is difficult, and the on-site operation is highly random, which affects the quality, cost control and secondary model development. In addition, the existing process control system does not have the ability to analyze, predict, and automatically control, and high temperature and dangerous areas require manual operation, which limits the development of intelligence. Summary of the invention

[0006] The present application is made in view of the above-mentioned problems, and its purpose is to provide a full-process intelligent refining system applied to the LF refining furnace, formulate relatively standard refining processes and charging rules, ensure the standardization and consistency of refining operations, use statistical methods, mechanism calculation and other technologies to establish mechanism models of each refining process, predict and automatically control the refining process, effectively improve the alloy composition hit rate and temperature compliance rate, while reducing alloy consumption and power consumption, reducing manpower investment, and realizing intelligent control of the entire refining process.

[0007] Specifically, the first aspect of the present application provides a full-process intelligent refining system applied to a LF refining furnace, comprising: The slag-making control module is used to calculate the amount of slag-making agent added during the refining process according to the mechanism model and is electrically connected to the main control module and the machine auxiliary module; The slag-forming agents for LF refining include but are not limited to lime, calcium carbide, aluminum particles, fluorite, and may also be materials such as lime and cement that can bring about desulfurization or deoxidation. The function of these slag-forming agents is to convert the oxidizing slag in the molten steel into reducing slag, thereby forming the so-called "white slag" to achieve the purpose of deep desulfurization and deoxidation. Specifically, lime is used to adjust the alkalinity of the slag, calcium carbide is used for desulfurization, and aluminum particles are used to further reduce the oxygen content in the slag. The main function of fluorite as a slag-forming agent is to reduce the melting point of the slag and improve the fluidity of the slag.

[0008] The temperature prediction module is used to pre-process the temperature data, predict and control the molten steel temperature in real time through the prediction model, and is electrically connected to the main control module and the machine auxiliary module; The preprocessing of temperature data includes data cleaning, missing value processing, and outlier processing to ensure the accuracy and completeness of the data. The purpose of data cleaning is to convert the raw data into a more structured and easy-to-analyze usable format.

[0009] The argon blowing control module is used to establish a relationship model between the exposed area of ​​molten steel and the bottom blowing argon gas flow rate based on experimental data and historical process experience, realize automatic argon blowing, and is electrically connected to the main control module and the machine auxiliary module; Wire feeding prediction module, used to calculate the feeding amount of aluminum wire and calcium wire according to the steel type and molten steel composition, and verify and optimize the feeding amount, and is electrically connected to the main control module and the machine auxiliary module; Aluminum wire is mainly used for deoxidation in the LF refining process. By adding aluminum wire to molten steel, the oxygen content in the steel can be effectively reduced, thereby improving the purity of the molten steel. It can also be used for alloying and adjusting the composition of the molten steel. The addition of aluminum wire helps to promote the floating of high-melting-point alumina inclusions, thereby reducing the number and area fraction of these inclusions in the ingot.

[0010] The addition of calcium wire is mainly used to change the morphology of alumina inclusions in molten steel, converting them into low-melting calcium aluminate inclusions, thereby improving the purity and fluidity of molten steel. Calcium treatment can effectively reduce the melting point of inclusions and ensure the stability of continuous casting operations. The feeding speed of calcium wire and the temperature of molten steel have a significant effect on the recovery rate of calcium. Appropriate feeding speed and higher molten steel temperature can improve the recovery rate of calcium.

[0011] The alloy calculation module is used to establish an alloy calculation model to realize automatic control of the amount of alloy addition according to the process parameters of each furnace and the conditions in the furnace, and is electrically connected to the main control module and the machine auxiliary module; The machine auxiliary module is used to collect the relevant data of refining in the furnace in real time, and send the collected data to the slag control module, temperature prediction module, wire feeding prediction module, alloy calculation module according to the needs, and perform sampling and slag dipping work through the industrial robot; The present invention uses industrial six-axis robots to perform temperature measurement, sampling and slag sticking work. These robots have high-precision motion control capabilities, can adapt to high-temperature environments, and support rapid fixture replacement and anti-collision detection functions.

[0012] The main control module is electrically connected to all other modules and the server, and is used to control system operation and exchange data with the server; The server is electrically connected to the main control module and is used for data storage and interaction.

[0013] Furthermore, the calculation formula for the amount of each slag-forming agent added in the slag-forming control module is as follows: ; ; ; ; ; ; ; in: is the amount of lime added during the refining process; The amount of lime added to the base of the steel grade; The total amount of slag added in the smelting process of this furnace is slag-breaking; is the basicity of the steel grade slag; is the difference between the sulfur content of molten steel and the target sulfur content; is the weight of molten steel; is the slag amount of the converter; is the amount of lime added after the converter; is the amount of fluorite added during the refining process; is the oxygen content of steel slag; The amount of ferrosilicon added to the converter; is the silicon content in ferrosilicon; The amount of silicon-manganese alloy added to the converter; is the silicon content in silicon manganese; sampling silicon content for the argon station; is the amount of calcium carbide added during the refining process; is the amount of converter deoxidizer added; is the amount of aluminum particles added during the refining process; is the amount of calcium carbide added; is the amount of aluminum particles added; It is the color grade of sticky residue; These are the calculation parameters obtained through linear programming based on the actual on-site refining data.

[0014] (Slag reduction coefficient), the value range is 0.05~0.3; (Sulfur content influence coefficient), the value range is 3000~20000; (Calculation coefficient of converter slag), the value range is 0.4~0.6; (Fluorite calculation coefficient), the value range is 0.1~0.5; (Calculation coefficient of silicon recovery rate and oxygen content in slag), the value range is ; (Calculation coefficient of converter slag and carbide addition), the value range is 0.08~0.12; (Calculation coefficient of converter deoxidizer addition and calcium carbide addition), the value range is 0.12~0.16; (Calculation coefficient of oxygen content in steel slag and amount of calcium carbide added), the value range is ; (Calculation coefficient of converter slag and aluminum granule addition), the value range is 0.07~0.14; (Calculation coefficient of converter deoxidizer addition and aluminum particle addition), the value range is 0.01~0.02; (Calculation coefficient of oxygen content in steel slag and amount of aluminum particles added), the value range is ; (Calculation coefficient of calcium carbide addition and aluminum particle addition), the value range is 0.08~0.12; (Additional calcium carbide and sticky residue color corresponding coefficient), the value range is 12~18; (Additional aluminum particles and sticky residue color correspondence coefficient), the value range is 4~8; Slag slag refers to the process of adding the remaining hot slag in the ladle to the next ladle to be refined during the LF furnace refining process to achieve recycling. This practice makes full use of the high basicity, low oxidation and low melting point characteristics of slag, thereby replacing part of the basic slag, reducing the consumption of raw and auxiliary materials such as lime for refining, shortening the refining slag making time, and improving the refining effect.

[0015] Furthermore, the color grade of the sticky residue specifically includes: 1) Black and foamy: oxidized slag, indicating that the content of FeO+MnO in the slag is >5%, and the color grade of sticky slag is 1; 2) Brown and gray: It indicates that the content of FeO+MnO in the slag is between 2% and 4%, and deoxidizer needs to be added. The color grade of sticky slag is 2; 3) Yellow: Deoxidation is in progress, add deoxidizer until white slag, the color grade of sticky slag is 3; 4) White slag, off-white: It indicates that most of the oxides in the slag are reduced, the deoxidation is good, and the color grade of the sticky slag is 4; 5) The slag is glassy and yellow-white: the final slag has good fluidity and good deoxidation, and the color grade of the sticky slag is 5.

[0016] Furthermore, the real-time temperature prediction formula of the temperature prediction module is: ; in: Predicting temperature for molten steel; Measure the temperature of molten steel; It is the heating rate of molten steel at different gears; To reduce the temperature of the furnace lining; To reduce the charge temperature; Temperature drop for argon blowing; To reduce the flue gas temperature; For the time interval.

[0017] The temperature drop of the furnace lining is the heat absorbed by the furnace lining, the temperature drop of the charge is the heat absorbed by the added alloy and slag, the temperature drop of argon blowing is the heat loss of argon blowing, and the temperature drop of the flue gas is the heat carried away by the smoke and flue gas.

[0018] Furthermore, the argon blowing control module specifically includes: Based on experimental data and historical process experience, a relationship model between the exposed area of ​​molten steel and the bottom blowing argon flow rate is established. Then, based on the real-time exposed area data of molten steel provided by the image processing unit, the required argon flow rate is calculated by the relationship model. Finally, the argon flow rate is automatically adjusted according to the deviation between the real-time monitored exposed area of ​​molten steel and the target value.

[0019] Furthermore, the calculation formula for the feeding amount of aluminum wire and calcium wire in the wire feeding prediction module is as follows: ; ; in: is the length of aluminum wire that needs to be added; is the target aluminum content of the steel grade; is the actual aluminum content of the steel grade; is the amount of oxidized and adsorbed aluminum; is the unit weight of the aluminum wire; is the aluminum content percentage of the aluminum wire; is the aluminum wire yield; is the weight of molten steel; is the length of calcium wire that needs to be added; For molten steel content; is the unit weight of calcium wire; is the calcium content percentage of the calcium line; is the calcium line yield; These are the calculation parameters obtained through linear programming based on the actual on-site refining data.

[0020] Furthermore, in the alloy calculation module, when only one alloy is used as a feed material for a certain element, the single alloy dosage model is as follows: ; in: is the amount of alloy added; The quality of molten steel; is the final mass fraction of the required elements in molten steel; is the initial mass fraction of the required element in the molten steel; is the yield of the required elements in the ith alloy; is the mass fraction of the required element in the ith alloy.

[0021] Furthermore, the machine-assisted module specifically includes: The relevant data of furnace refining are collected in real time through sensors and system equipment. The system measuring gun automatically installs the probe according to the needs of temperature measurement, sampling and slag sticking through the industrial six-axis robot, and inserts the probe into the molten steel in the ladle for temperature measurement and sampling. The depth of the probe inserted into the molten steel is accurately located by detecting the height position signal of the ladle slag liquid level, and it is placed in a fixed position after sampling.

[0022] Furthermore, the furnace refining related data specifically include: steel grade, molten steel surface image, molten steel weight, total amount of slag added in the slag-breaking furnace smelting process, basicity of steel grade slag, sulfur content in molten steel, amount of slag under converter, amount of ferrosilicon added to converter, amount of silicon-manganese alloy added to converter, amount of converter deoxidizer added, actual aluminum content of steel grade, and alumina content in molten steel.

[0023] Furthermore, the specific refining process of the full-process intelligent refining system is as follows: The ladle car arrives - the furnace cover drops - the dust removal valve opens - strong blowing to break the slag - the robot measures temperature - the slag and alloy are automatically calculated and sent - medium blowing and stirring - automatic calculation of aluminum wire feeding - lower electrode heating - lifting the electrode to stop heating - the robot measures temperature and takes samples to stick to the slag - strong blowing for desulfurization - automatic feeding of alloy - secondary aluminum feeding - the robot measures temperature and takes samples to stick to the slag - lower electrode heating - the robot measures temperature and takes samples to stick to the slag - lifting the electrode to stop heating - automatic soft blowing - automatic calcium feeding - secondary soft blowing - the dust removal valve closes - the argon gas is closed - the ladle leaves the station.

[0024] The strong blowing for slag breaking, medium blowing for stirring, strong blowing for desulfurization, automatic soft blowing and secondary soft blowing in this process are controlled by the argon blowing control module; the robot temperature measurement and sampling for slag sticking is controlled by the machine auxiliary module; the automatic calculation and distribution of alloys, and the automatic feeding and alloy replenishment are controlled by the alloy calculation module; the automatic calculation of aluminum wire feeding, secondary aluminum replenishment and automatic calcium feeding are controlled by the wire feeding prediction model; the lower electrode heating and the lifting electrode stopping heating are controlled by the temperature prediction model; the automatic calculation and distribution of slag is controlled by the slag making control model.

[0025] The flow rate and intensity of bottom blowing argon are divided into three modes: soft blowing, medium blowing and strong blowing. The flow rate of soft blowing argon is low, usually 80 L / min, and is mainly used to make non-metallic impurities in molten steel float and remove them, thereby improving the cleanliness of molten steel. In the LF refining process, the soft blowing stage can effectively remove inclusions larger than 10μm and significantly reduce the average size of inclusions. In addition, soft blowing can also make inclusions float through weak stirring and reduce the floating time.

[0026] Middle blowing: The middle blowing argon flow is moderate, usually 200 L / min, and is mainly used to stabilize the heating stage, and maintain the uniformity of molten steel temperature and composition through medium-intensity stirring. In the automatic mode of LF refining, the middle blowing stage usually lasts 3-5 minutes to ensure the uniformity of molten steel temperature and composition.

[0027] Strong blowing: Strong blowing has a high argon flow rate, usually 500 L / min, and is mainly used in the slag desulfurization stage to promote the removal of sulfur and other harmful elements in the molten steel through high-intensity stirring. In the automatic mode of LF refining, the strong blowing stage also lasts 3-5 minutes to ensure that the sulfur content in the molten steel is reduced to the target level.

[0028] In the second aspect, the present application also provides a computing device, which has the function of implementing the method described in the first aspect above. The beneficial effects can be found in the description of the first aspect, which will not be repeated here. The function can be implemented by hardware, or by executing the corresponding software implementation through hardware. The hardware or software includes one or more modules corresponding to the above functions. In one possible design, the structure of the device includes an acquisition module, a training module, and optionally, a construction module. These modules can implement the function of the training node in the method example of the first aspect above. Please refer to the detailed description in the method example for details, which will not be repeated here.

[0029] In the third aspect, the present application also provides a computing device, which is used to implement the functions of the method described in the first aspect above. The beneficial effects can be found in the description of the first aspect and will not be repeated here. The structure of the computing device includes a processor and a memory, and the memory is used to store instructions and / or data. The memory is coupled to the processor, and when the processor executes the program instructions stored in the memory, the function of the training node in the example of the first aspect above can be implemented. The structure of the computing device also includes a communication interface for communicating with other devices.

[0030] In a fourth aspect, the present application also provides a computer-readable storage medium, in which instructions are stored, and when the computer-readable storage medium is run on a computer, the computer executes the method in the above-mentioned first aspect and various possible designs of the first aspect.

[0031] In a fifth aspect, the present application also provides a computer program product comprising instructions, which, when executed on a computer, enables the computer to execute the method in the above-mentioned first aspect and various possible designs of the first aspect.

[0032] In a sixth aspect, the present application also provides a computing chip, which is connected to a memory, and the chip is used to read and execute a software program stored in the memory, and to execute the methods in the above-mentioned first aspect and various possible implementation methods of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present drawings or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present drawings. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0034] Figure 1 It is a structural schematic diagram of the present invention; The purpose, features and advantages of this figure will be further described in conjunction with the embodiments with reference to the accompanying drawings. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0036] Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. In addition, it can also be understood that although the efforts made in this development process may be complicated and lengthy, for ordinary technicians in this field related to the content disclosed in this application, some changes in design, manufacturing or production based on the technical content disclosed in this application are just conventional technical means, and should not be understood as insufficient content disclosed in this application.

[0037] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0038] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0039] If there is no special explanation, all steps of the present application can be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), which means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0040] If there is no special explanation, the "include" and "comprising" mentioned in this application are open-ended or closed-ended. For example, the "include" and "comprising" may mean that other components not listed may also be included or only the listed components may be included or only the listed components may be included.

[0041] If not specifically stated, in this application, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0042] In order to better understand the solutions of the embodiments of the present application, some relevant terms and concepts that may be involved in the embodiments of the present application are first introduced below.

[0043] (1) Refining. Steel refining is a vital part of the steel production process. Its purpose is to remove impurities in pig iron, such as sulfur and phosphorus, and adjust the composition of steel to meet the needs of specific uses. The refining process usually includes two stages: primary refining and secondary refining. In the primary refining stage, pig iron is preliminarily treated by a converter or an electric arc furnace. The main task of this stage is to remove carbon and other impurities such as sulfur and phosphorus in the pig iron, and to perform alloying at the same time to obtain molten steel with basic properties. Secondary refining, also known as off-furnace refining, is carried out after primary refining. Off-furnace refining can be carried out under vacuum, inert gas or reducing atmosphere to further remove gases and harmful impurities.

[0044] (2) LF refining, or Ladle Furnace Refining, is an important secondary refining process in steel production. Its main purpose is to further treat the primary molten steel to meet the requirements of the continuous casting process and improve the quality and stability of the molten steel. LF refining has many advantages, including precise composition adjustment, reduction of non-metallic inclusions, and excellent temperature control capabilities.

[0045] The basic principle of LF refining is to refine molten steel in a reducing atmosphere using basic synthetic slag, submerged arc heating and argon stirring. This process can effectively reduce the oxygen and sulfur content in steel, and adjust the composition and temperature of molten steel by adding alloys and slag.

[0046] (3) LF refining furnace, i.e. ladle refining furnace, is an important refining equipment outside the furnace, which is widely used in steel production. It achieves the refining effects of deoxidation, desulfurization, alloying and heating of molten steel through arc heating, reducing atmosphere, white slag refining and gas stirring, ensures the accurate composition and uniform temperature of molten steel, effectively purifies molten steel, coordinates steelmaking and continuous casting processes, and ensures continuous casting of multiple furnaces.

[0047] In this embodiment, Figure 1 As shown, a full-process intelligent refining system applied to LF refining furnace includes: The slag-making control module is used to calculate the amount of slag-making agent added during the refining process according to the mechanism model and is electrically connected to the main control module and the machine auxiliary module; The slag-forming agents for LF refining mainly include lime, calcium carbide, aluminum particles, and fluorite. The function of these slag-forming agents is to convert the oxidizing slag in the molten steel into reducing slag, thereby forming the so-called "white slag" to achieve the purpose of deep desulfurization and deoxidation. Specifically, lime is used to adjust the alkalinity of the slag, calcium carbide is used for desulfurization, and aluminum particles are used to further reduce the oxygen content in the slag. The main function of fluorite as a slag-forming agent is to reduce the melting point of the slag and improve the fluidity of the slag.

[0048] The temperature prediction module is used to pre-process the temperature data, predict and control the molten steel temperature in real time through the prediction model, and is electrically connected to the main control module and the machine auxiliary module; The preprocessing of temperature data includes data cleaning, missing value processing, and outlier processing to ensure the accuracy and completeness of the data. The purpose of data cleaning is to convert the raw data into a more structured and easy-to-analyze usable format.

[0049] The argon blowing control module is used to establish a relationship model between the exposed area of ​​molten steel and the bottom blowing argon gas flow rate based on experimental data and historical process experience, realize automatic argon blowing, and is electrically connected to the main control module and the machine auxiliary module; Wire feeding prediction module, used to calculate the feeding amount of aluminum wire and calcium wire according to the steel type and molten steel composition, and verify and optimize the feeding amount, and is electrically connected to the main control module and the machine auxiliary module; Aluminum wire is mainly used for deoxidation in the LF refining process. By adding aluminum wire to molten steel, the oxygen content in the steel can be effectively reduced, thereby improving the purity of the molten steel. It can also be used for alloying and adjusting the composition of the molten steel. The addition of aluminum wire helps to promote the floating of high-melting-point alumina inclusions, thereby reducing the number and area fraction of these inclusions in the ingot.

[0050] The addition of calcium wire is mainly used to change the morphology of alumina inclusions in molten steel, converting them into low-melting calcium aluminate inclusions, thereby improving the purity and fluidity of molten steel. Calcium treatment can effectively reduce the melting point of inclusions and ensure the stability of continuous casting operations. The feeding speed of calcium wire and the temperature of molten steel have a significant effect on the recovery rate of calcium. Appropriate feeding speed and higher molten steel temperature can improve the recovery rate of calcium.

[0051] The alloy calculation module is used to establish an alloy calculation model to realize automatic control of the amount of alloy addition according to the process parameters of each furnace and the conditions in the furnace, and is electrically connected to the main control module and the machine auxiliary module; The machine auxiliary module is used to collect the relevant data of refining in the furnace in real time, and send the collected data to the slag control module, temperature prediction module, wire feeding prediction module, alloy calculation module according to the needs, and perform sampling and slag dipping work through the industrial robot; The present invention uses industrial six-axis robots to perform temperature measurement, sampling and slag sticking work. These robots have high-precision motion control capabilities, can adapt to high-temperature environments, and support rapid fixture replacement and anti-collision detection functions.

[0052] The main control module is electrically connected to all other modules and the server, and is used to control system operation and exchange data with the server; The server is electrically connected to the main control module and is used for data storage and interaction.

[0053] Furthermore, the calculation formula for the amount of each slag-forming agent added in the slag-forming control module is as follows: ; ; ; ; ; ; ; In this embodiment, the values ​​of the coefficients are as follows: (slag reduction coefficient), the value is 0.2; (sulfur content influence coefficient), the value is 10000; (Calculation coefficient of converter slag), the value is 0.5; (Fluorite calculation coefficient), the value range is 0.1~0.5; (Calculation coefficient of silicon recovery rate and oxygen content in slag), the value is ; (Calculation coefficient of converter slag and carbide addition), the value is 0.1; (Calculation coefficient of converter deoxidizer addition and calcium carbide addition), the value is 0.15; (Calculation coefficient of oxygen content in steel slag and amount of calcium carbide added), the value is ; (Calculation coefficient of converter slag and aluminum granule addition), the value is 0.1; (Calculation coefficient of converter deoxidizer addition and aluminum particle addition), the value is 0.01; (Calculation coefficient of oxygen content in steel slag and amount of aluminum particles added), the value is ; (Calculation coefficient of calcium carbide addition and aluminum particle addition), the value is 0.1; (Additional calcium carbide and sticky residue color corresponding coefficient), the value is 15; (The color correspondence coefficient of the added aluminum particles and the sticky residue), the value is 6; In this embodiment, the basic lime addition amount is 400kg, the slag is 100kg, k1 is 0.2, the sulfur content entering the station is 0.025, the sulfur content of the standard brick is 0.03, then %S is 0.005, k2 is 10000, the slag amount under the converter is 100kg, k3 is 0.5, and 100kg of lime is added after the converter. Then 380kg of lime needs to be added to the first batch of this steel grade.

[0054] k4 is set to 0.3, and the first batch of fluorite added is calculated based on the first batch of lime added, which is 114kg; The silicon recovery rate is 0.6, k5 is , then the oxygen content of steel slag is 40ppm; Add 700kg of deoxidizer (ferrosilicon, silicon manganese, etc.) to the converter, 100kg of slag, k6 is 0.1, k7 is 0.15, k8 is , then you need to add 140kg of calcium carbide; k9 is 0.1, k10 is 0.01, and k11 is , k12 is 0.1, then 41kg of aluminum particles need to be added; k13 is 15, k14 is 6, the color of the sticky slag is black, that is, the color grades are 5, then 30kg of aluminum particles need to be added.

[0055] Slag slag refers to the process of adding the remaining hot slag in the ladle to the next ladle to be refined during the LF furnace refining process to achieve recycling. This practice makes full use of the high basicity, low oxidation and low melting point characteristics of slag, thereby replacing part of the basic slag, reducing the consumption of raw and auxiliary materials such as lime for refining, shortening the refining slag making time, and improving the refining effect.

[0056] Furthermore, the color grade of sticky residue includes: 1) Black and foamy: oxidized slag, indicating that the content of FeO+MnO in the slag is >5%, and the color grade of sticky slag is 1; 2) Brown and gray: It indicates that the content of FeO+MnO in the slag is between 2% and 4%, and deoxidizer needs to be added. The color grade of sticky slag is 2; 3) Yellow: Deoxidation is in progress, add deoxidizer until white slag, the color grade of sticky slag is 3; 4) White slag, off-white: It indicates that most of the oxides in the slag are reduced, the deoxidation is good, and the color grade of the sticky slag is 4; 5) The slag is glassy and yellow-white: the final slag has good fluidity and good deoxidation, and the color grade of the sticky slag is 5.

[0057] Furthermore, the real-time temperature prediction formula of the temperature prediction module is: ; In this embodiment, the measured temperature is 1550°C, the molten steel heating rate at level 5 is 4°C / min, the furnace lining temperature drops to -0.5°C / min, the charge temperature drops to -0.5°C / min, the argon blowing temperature drops to -1°C / min, the smoke dust temperature drops to -0.5°C / min, and the time is 10 minutes, so the predicted temperature is 1565°C.

[0058] The temperature drop of the furnace lining is the heat absorbed by the furnace lining, the temperature drop of the charge is the heat absorbed by the added alloy and slag, the temperature drop of argon blowing is the heat loss of argon blowing, and the temperature drop of the flue gas is the heat carried away by the smoke and flue gas.

[0059] Furthermore, the argon blowing control module specifically includes: Based on experimental data and historical process experience, a relationship model between the exposed area of ​​molten steel and the bottom blowing argon flow rate is established. Then, based on the real-time exposed area data of molten steel provided by the image processing unit, the required argon flow rate is calculated by the relationship model. Finally, the argon flow rate is automatically adjusted according to the deviation between the real-time monitored exposed area of ​​molten steel and the target value.

[0060] Furthermore, the calculation formula for the feeding amount of aluminum wire and calcium wire in the wire feeding prediction module is as follows: ; ; in: is the length of aluminum wire that needs to be added; is the target aluminum content of the steel grade; is the actual aluminum content of the steel grade; is the amount of oxidized and adsorbed aluminum; is the unit weight of the aluminum wire; is the aluminum content percentage of the aluminum wire; is the aluminum wire yield; is the weight of molten steel; is the length of calcium wire that needs to be added; For molten steel content; is the unit weight of calcium wire; is the calcium content percentage of the calcium line; is the calcium line yield; These are the calculation parameters obtained through linear programming based on the actual on-site refining data.

[0061] Furthermore, in the alloy calculation module, when only one alloy is used as a feed material for a certain element, the single alloy dosage model is as follows: ; In this embodiment, the target aluminum content of the steel grade is 0.05, the aluminum content of the molten steel entering the station is 0.03, the aluminum content consumed by oxidation adsorption is 0.01%, the unit weight of the aluminum wire is 0.03 (kg / m), the aluminum content of the aluminum wire is 98%, the aluminum recovery rate is 60%, the weight of the molten steel is 130t, and the length of the aluminum wire to be added is 221m.

[0062] In this embodiment, the aluminum oxide content of the steel is 0.11, the aluminum content of the molten steel entering the station is 0.03%, the aluminum content consumed by oxidation and adsorption is 0.01%, the unit weight of the aluminum wire is 0.035 (kg / m), the calcium content of the calcium wire is 98%, the calcium recovery rate is 60%, k is 1, and the length of the calcium wire to be added is 119m.

[0063] Furthermore, the machine-assisted module specifically includes: The relevant data of furnace refining are collected in real time through sensors and system equipment. The system measuring gun automatically installs the probe according to the needs of temperature measurement, sampling and slag sticking through the industrial six-axis robot, and inserts the probe into the molten steel in the ladle for temperature measurement and sampling. The depth of the probe inserted into the molten steel is accurately located by detecting the height position signal of the ladle slag liquid level, and it is placed in a fixed position after sampling.

[0064] Furthermore, the data related to furnace refining include: steel grade, molten steel surface image, molten steel weight, total amount of slag added in the slag-breaking furnace smelting process, basicity of steel grade slag, sulfur content in molten steel, amount of slag in converter, amount of ferrosilicon added in converter, amount of silicon-manganese alloy added in converter, amount of deoxidizer added in converter, actual aluminum content in steel grade, and alumina content in molten steel.

[0065] Furthermore, the specific refining process of the full-process intelligent refining system is as follows: The ladle car arrives - the furnace cover drops - the dust removal valve opens - strong blowing to break the slag - the robot measures temperature - the slag and alloy are automatically calculated and sent - medium blowing and stirring - automatic calculation of aluminum wire feeding - lower electrode heating - lifting the electrode to stop heating - the robot measures temperature and takes samples to stick to the slag - strong blowing for desulfurization - automatic feeding of alloy - secondary aluminum feeding - the robot measures temperature and takes samples to stick to the slag - lower electrode heating - the robot measures temperature and takes samples to stick to the slag - lifting the electrode to stop heating - automatic soft blowing - automatic calcium feeding - secondary soft blowing - the dust removal valve closes - the argon gas is closed - the ladle leaves the station.

[0066] The strong blowing for slag breaking, medium blowing for stirring, strong blowing for desulfurization, automatic soft blowing and secondary soft blowing in this process are controlled by the argon blowing control module; the robot temperature measurement and sampling for slag sticking is controlled by the machine auxiliary module; the automatic calculation and distribution of alloys, and the automatic feeding and alloy replenishment are controlled by the alloy calculation module; the automatic calculation of aluminum wire feeding, secondary aluminum replenishment and automatic calcium feeding are controlled by the wire feeding prediction model; the lower electrode heating and the lifting electrode stopping heating are controlled by the temperature prediction model; the automatic calculation and distribution of slag is controlled by the slag making control model.

[0067] The flow rate and intensity of bottom blowing argon are divided into three modes: soft blowing, medium blowing and strong blowing. The flow rate of soft blowing argon is low, usually 80 L / min, and is mainly used to make non-metallic impurities in molten steel float and remove them, thereby improving the cleanliness of molten steel. In the LF refining process, the soft blowing stage can effectively remove inclusions larger than 10μm and significantly reduce the average size of inclusions. In addition, soft blowing can also make inclusions float through weak stirring and reduce the floating time.

[0068] Middle blowing: The middle blowing argon flow is moderate, usually 200 L / min, and is mainly used to stabilize the heating stage, and maintain the uniformity of molten steel temperature and composition through medium-intensity stirring. In the automatic mode of LF refining, the middle blowing stage usually lasts 3-5 minutes to ensure the uniformity of molten steel temperature and composition.

[0069] Strong blowing: Strong blowing has a high argon flow rate, usually 500 L / min, and is mainly used in the slag desulfurization stage to promote the removal of sulfur and other harmful elements in the molten steel through high-intensity stirring. In the automatic mode of LF refining, the strong blowing stage also lasts 3-5 minutes to ensure that the sulfur content in the molten steel is reduced to the target level.

[0070] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A full-process intelligent refining system applied to LF refining furnace, characterized in that: include: The slag-making control module is used to calculate the amount of slag-making agent added during the refining process according to the mechanism model and is electrically connected to the main control module and the machine auxiliary module; The temperature prediction module is used to pre-process the temperature data, predict and control the molten steel temperature in real time through the prediction model, and is electrically connected to the main control module and the machine auxiliary module; The argon blowing control module is used to establish a relationship model between the exposed area of ​​molten steel and the bottom blowing argon gas flow rate based on experimental data and historical process experience, realize automatic argon blowing, and is electrically connected to the main control module and the machine auxiliary module; Wire feeding prediction module, used to calculate the feeding amount of aluminum wire and calcium wire according to the steel type and molten steel composition, and verify and optimize the feeding amount, and is electrically connected to the main control module and the machine auxiliary module; The alloy calculation module is used to establish an alloy calculation model to realize automatic control of the amount of alloy addition according to the process parameters of each furnace and the conditions in the furnace, and is electrically connected to the main control module and the machine auxiliary module; The machine auxiliary module is used to collect the relevant data of refining in the furnace in real time, and send the collected data to the slag control module, temperature prediction module, wire feeding prediction module, alloy calculation module according to the needs, and perform sampling and slag dipping work through the industrial robot; The main control module is electrically connected to all other modules and the server, and is used to control system operation and exchange data with the server; The server is electrically connected to the main control module and is used for data storage and interaction.

2. A full-process intelligent refining system applied to LF refining furnace according to claim 1, characterized in that: The calculation formula for the amount of each slag-forming agent added in the slag-forming control module is as follows: ； ； ； ； ； ； ； in: is the amount of lime added during the refining process; The amount of lime added to the base of the steel grade; The total amount of slag added in the smelting process of this furnace is slag-breaking; The basicity of the steel grade slag; is the difference between the sulfur content of molten steel and the target sulfur content; is the weight of molten steel; is the slag amount of the converter; is the amount of lime added after the converter; is the amount of fluorite added during the refining process; is the oxygen content of steel slag; The amount of ferrosilicon added to the converter; is the silicon content in ferrosilicon; The amount of silicon-manganese alloy added to the converter; is the silicon content in silicon manganese; sampling silicon content for the argon station; is the amount of calcium carbide added during the refining process; is the amount of converter deoxidizer added; is the amount of aluminum particles added during the refining process; is the amount of calcium carbide added; is the amount of aluminum particles added; It is the color grade of sticky residue; These are the calculation parameters obtained through linear programming based on the actual on-site refining data.

3. A full-process intelligent refining system applied to LF refining furnace according to claim 2, characterized in that: The sticky residue color grades specifically include: 1) Black and foamy: oxidized slag, indicating that the content of FeO+MnO in the slag is >5%, and the color grade of sticky slag is 1; 2) Brown and gray: It indicates that the content of FeO+MnO in the slag is between 2% and 4%, and deoxidizer needs to be added. The color grade of sticky slag is 2; 3) Yellow: Deoxidation is in progress, add deoxidizer until white slag, the color grade of sticky slag is 3; 4) White slag, off-white: It indicates that most of the oxides in the slag are reduced, the deoxidation is good, and the color grade of the sticky slag is 4; 5) The slag is glassy and yellow-white: the final slag has good fluidity and good deoxidation, and the color grade of the sticky slag is 5.

4. The full-process intelligent refining system applied to LF refining furnace according to claim 1 is characterized in that: The real-time temperature prediction formula of the temperature prediction module is: ； in: Predicting temperature for molten steel; Measure the temperature of molten steel; It is the heating rate of molten steel at different gears; To reduce the temperature of the furnace lining; To reduce the charge temperature; Temperature drop for argon blowing; To reduce the flue gas temperature; For the time interval.

5. The full-process intelligent refining system applied to LF refining furnace according to claim 1 is characterized in that: The argon blowing control module specifically includes: Based on experimental data and historical process experience, a relationship model between the exposed area of ​​molten steel and the bottom blowing argon flow rate is established. Then, based on the real-time exposed area data of molten steel provided by the image processing unit, the required argon flow rate is calculated by the relationship model. Finally, the argon flow rate is automatically adjusted according to the deviation between the real-time monitored exposed area of ​​molten steel and the target value.

6. The full-process intelligent refining system applied to LF refining furnace according to claim 1 is characterized in that: The calculation formula for the feeding amount of aluminum wire and calcium wire in the wire feeding prediction module is as follows: ； ； in: is the length of aluminum wire that needs to be added; is the target aluminum content of the steel grade; is the actual aluminum content of the steel grade; is the amount of oxidized and adsorbed aluminum; is the unit weight of the aluminum wire; is the aluminum content percentage of the aluminum wire; is the aluminum wire yield; is the weight of molten steel; is the length of calcium wire that needs to be added; For molten steel content; is the unit weight of calcium wire; is the calcium content percentage of the calcium line; is the calcium line yield; These are the calculation parameters obtained through linear programming based on the actual on-site refining data.

7. The full-process intelligent refining system applied to LF refining furnace according to claim 1 is characterized in that: In the alloy calculation module, when only one alloy is used as a feed material for a certain element, the single alloy dosage model is as follows: ； in: is the amount of alloy added; The quality of molten steel; is the final mass fraction of the required elements in molten steel; is the initial mass fraction of the required element in the molten steel; is the yield of the required elements in the ith alloy; is the mass fraction of the required element in the ith alloy.

8. The full-process intelligent refining system applied to LF refining furnace according to claim 1 is characterized in that: The machine auxiliary module specifically includes: The relevant data of furnace refining are collected in real time through sensors and system equipment. The system measuring gun automatically installs the probe according to the needs of temperature measurement, sampling and slag sticking through the industrial six-axis robot, and inserts the probe into the molten steel in the ladle for temperature measurement and sampling. The depth of the probe inserted into the molten steel is accurately located by detecting the height position signal of the ladle slag liquid level, and it is placed in a fixed position after sampling.

9. A full-process intelligent refining system applied to LF refining furnace according to claim 8, characterized in that: The furnace refining related data specifically include: steel grade, molten steel surface image, molten steel weight, total amount of slag added in the slag-breaking furnace smelting process, basicity of steel grade slag, sulfur content in molten steel, slag amount in converter, amount of ferrosilicon added in converter, amount of silicon-manganese alloy added in converter, amount of deoxidizer added in converter, actual aluminum content in steel grade, and alumina content in molten steel.

10. The full-process intelligent refining system applied to LF refining furnace according to claim 1 is characterized in that: The specific refining process of the full-process intelligent refining system is as follows: The ladle car arrives - the furnace cover drops - the dust removal valve opens - strong blowing to break the slag - the robot measures temperature - the slag and alloy are automatically calculated and sent - medium blowing and stirring - automatic calculation of aluminum wire feeding - lower electrode heating - lifting the electrode to stop heating - the robot measures temperature and takes samples to stick to the slag - strong blowing for desulfurization - automatic feeding of alloy - secondary aluminum feeding - the robot measures temperature and takes samples to stick to the slag - lower electrode heating - the robot measures temperature and takes samples to stick to the slag - lifting the electrode to stop heating - automatic soft blowing - automatic calcium feeding - secondary soft blowing - the dust removal valve closes - the argon gas is closed - the ladle leaves the station.

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