A low-cost alloy calculation method for converters applicable to all steel grades

Abstract

The present invention relates to a method for calculating low-cost alloys in a converter applicable to all steel grades, belonging to the field of alloy calculation. It obtains the amounts of hot metal and scrap charged into the converter, calculates the amount of molten steel tapped from the converter, limits the range of the charged amount in the converter to ensure that the amount of molten steel is calculated based on the minimum charged amount; obtains the measured values of TSC and TSO in the converter and the results of the in-process molten steel analysis, and judges the oxygen content at the end point of the converter and the residual manganese and carbon contents at the end point of the converter; sets the alloy type requirements for general steel grades and special steel grades; automatically adjusts the target values of the steel grade components; dynamically calculates the alloy recovery rate according to the alloy amounts required for different steel grades; sets the upper limit of the carburizer according to the use characteristics of the carburizer; calculates the alloys respectively according to the end-point target of the converter, the blowing stop of the converter, and the TSO measurement results and after self-learning correction of the measurement data; sets the alloy information and the steel grade target component database; obtains the steel grade and the target component control values for the current heat of smelting; automatically calculates the alloys and automatically downloads them to the first-level machine for alloy weighing, with the optimal alloy calculation cost.

Description

Technical Field

[0001] The present invention belongs to the field of alloy calculation, and relates to a converter low-cost alloy calculation method applicable to all steel grades. Background Art

[0002] In the existing converter tapping alloying process, the tapping amount is usually judged based on the charging amount experience, and the alloy types and quantities are manually calculated according to the steel grade composition requirements; it adopts a general alloy model control, and the applicable steel grade conditions are limited; 3. Due to the simple variety structure, the alloy types and quantities are relatively fixed, and a fixed alloy model is used to calculate the alloy addition amount. In the above methods, the manual experience judgment type deoxidation alloying not only results in a low narrow composition hit rate of the steel grade, but also it is difficult to ensure the lowest alloy cost when the alloy structure is complex, which not only affects the quality of molten steel but also leads to an increase in production costs; although the existing alloy models adopt linear calculation and regression calculation, when there are many steel grade types, the requirements for alloy types are also very complex, and they cannot handle the alloy calculations of all steel grades, resulting in poor adaptability of the alloy model and unable to be widely promoted. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a converter low-cost alloy calculation model applicable to all steel grades. This method can calculate the alloy types and quantities in the optimal alloy cost manner, achieve precise control of the steel grade composition, improve the quality of molten steel, reduce the alloy cost, and reduce the labor intensity of operators.

[0004] To achieve the above purpose, the present invention provides the following technical solutions:

[0005] A converter low-cost alloy calculation method applicable to all steel grades, comprising the following steps:

[0006] S1: Automatically obtain the amount of hot metal and scrap charged into the converter, calculate the converter tapping amount according to the metal charge yield of different types, consider the basic data maintenance, limit the converter charging amount range, and ensure that the tapping amount is calculated based on the minimum charging amount;

[0007] S2: Automatically obtain the measured values of TSC and TSO of the converter and the process molten steel test results, and combine dynamic calculation and self-learning to judge the converter end oxygen content and the converter end residual manganese and carbon contents;

[0008] S3: The alloy model sets the alloy type requirements for general steel grades and special steel grades, and adapts to the alloy calculation required for all steel grades. The alloy types of the special steel grades mainly refer to the steel grades with uncommon alloys used in daily production, which are set according to the requirements of different steel mills. For example, carbon manganese balls are not commonly used in the daily converter alloying process (except for the steel grades that require carbon manganese balls, no stock is prepared), and they are only used when producing steel grades with high carbon content, such as No. 45 steel. After adding carbon manganese balls to the molten steel, it will increase carbon and manganese, which will affect the calculation of common alloys (such as ferrosilicon, high-carbon ferromanganese, low-carbon ferromanganese, silicomanganese alloy, etc.). Therefore, an interface for the alloy type requirements of special molten steel is added, and a separate alloy calculation interface is set for the steel grades that require uncommon alloys. During the alloy calculation process, after detecting that the currently produced steel grade requires special alloys, the required amount of special alloys will be automatically matched, and the remaining components will be allocated by common alloys.

[0009] S4: Automatically adjust the target values of the steel grade components according to different process paths.

[0010] S5: Dynamically calculate the alloy yield according to the alloy amount required for different steel grades.

[0011] S6: Set the upper limit of the recarburizer according to the usage characteristics of the recarburizer. When the required carbon addition amount exceeds the upper limit of the recarburizer, use alloys to add carbon.

[0012] S7: Calculate the alloy statically according to the target at the end of the converter, calculate the alloy dynamically when the converter stops blowing, and calculate the alloy again according to the TSO measurement results and after self-learning and correction of the measurement data.

[0013] S8: The alloy model sets the alloy type, composition and unit price database to guide the low-cost calculation of the alloy model; sets the target composition database of the steel grade to guide the alloy model to calculate the alloy according to the target composition of the steel grade; the alloy model also automatically obtains the steel grade and the target value of the composition control for the current heat of smelting.

[0014] S9: Automatically calculate the alloy and automatically download it to the first-level machine for alloy weighing, and the alloy calculation cost is the most optimal.

[0015] Furthermore, in step S1, the alloy model automatically obtains the amount of hot metal and scrap charged into the converter, calculates the tapping amount of the converter according to the yield of different metal materials, considers the maintenance of basic data, limits the range of the converter charge amount and ensures the calculation of the tapping amount with the minimum charge amount, specifically including:

[0016] S11: After the converter smelting starts, the alloy model automatically obtains the amount of hot metal and scrap for the current heat, and calculates the tapping amount of the converter according to the yield. The yield of the main raw material hot metal and the main raw material iron lumps is 0.93, the yield of the main raw material steel edges and the main raw material heavy scrap is 0.95, and the yield of the main raw material slag steel for steelmaking is 0.65.

[0017] S12: Introduce an automatic correction mechanism for the charging quantity error, set the value of the fixed charging quantity of the converter and the range value of hot metal, and when the scrap information is missing in the charging quantity, the model automatically calculates the scrap quantity according to the predetermined charging quantity and predicts the tapping quantity at the same time;

[0018] The automatic calculation of the scrap quantity according to the predetermined charging quantity specifically includes:

[0019] Scrap quantity = Predetermined total charging quantity - Hot metal weight - Scrap weight in ladle plus scrap

[0020] Among them, the predetermined total charging quantity is adjusted according to the actual demand of the current production of the converter. Taking the hot metal weight and the scrap quantity in ladle plus scrap as fixed quantities and the scrap quantity in the scrap bucket as a variable, after automatically obtaining the hot metal weight and the scrap quantity in ladle plus scrap, if the weight of the scrap bucket is missing, then according to the error correction mechanism, the scrap weight charged into the scrap bucket is automatically calculated according to the preset total charging quantity; but when both the hot metal quantity and the scrap quantity in ladle plus scrap cannot be obtained, the scrap quantity in the scrap bucket cannot be automatically calculated, and only the tapping quantity of the current heat is calculated according to the charging system of the previous heat;

[0021] The specific steps for predicting the tapping quantity are as follows: According to the hot metal weight, the types and weights of scrap in ladle plus scrap, and the types and weights of scrap added to the scrap bucket, calculate the tapping quantity of the current heat according to the recovery rates of the corresponding raw materials.

[0022] Furthermore, the automatic acquisition of the TSC and TSO measurement values of the converter and the process molten steel test results in step S2, and the combination of dynamic calculation and self-learning to judge the oxygen content at the end point of the converter and the residual manganese and carbon contents at the end point of the converter specifically includes:

[0023] S21: Calculate the residual manganese content at the end point of the converter using a regression equation, and the parameters of the regression equation are dynamically corrected according to the test results of the end-point sample of the converter to ensure the accuracy of the residual manganese at the end point. Specifically as follows:

[0024] Residual manganese at the end point of the converter = 0.7926 + 0.1862 * Hot metal manganese content - 0.000066 * Oxygen content at the end point of the converter - 0.000432 * Temperature at the end point of the converter

[0025] The end-point data of the converter is obtained through the TSO measurement of the sublance on the one hand, and on the other hand, the following dynamic calculations are carried out: When there is sublance TSO data, the optimized sublance data is used to calculate the residual manganese at the end point of the converter. When there is no TSO data, the end-point data of the converter is dynamically calculated according to the TSC data; if there is no sublance TSC or TSO data, the end-point residual manganese is calculated by comparing historical data; Every 10 - 20 heats of valid data will automatically calculate the coefficients through the regression equation, and the calculated coefficients will be automatically assigned to the converter residual manganese calculation formula, and it is selected whether to use the coefficients for automatic calculation and correction;

[0026] S12: After the TSC measurement of the converter, it enters dynamic smelting. The alloy model predicts the oxygen content, residual manganese, and residual carbon at the end of the converter according to the target steel grade composition and the TSC measurement results.

[0027] During the converter smelting process, first obtain the specific composition range and target composition of the steel grade produced in this furnace, and calculate the target temperature and composition at the end of the converter according to the process route and target composition; when the TSC measures the molten bath temperature and carbon content, according to the calculated target temperature and composition, dynamically calculate the actually hit temperature and composition at the end according to the oxygen supply amount; when the process route is BC or BRC, the model, according to the TSC results, under the condition of preferentially hitting the temperature, through the calculated dynamic oxygen supply amount, tries to ensure carbon hitting; when the process route is BLC or BLRC, carbon is preferentially hit under the condition of ensuring the lowest tapping temperature; according to the hitting principles of different process routes, combined with the actual dynamic oxygen supply amount, calculate the oxygen content at the end, and at the same time, the calculated end temperature and end oxygen, combined with the hot metal conditions, calculate the residual manganese content at the end.

[0028] S13: After the TSO measurement, predict the residual manganese and carbon at the end again according to the TSO measurement results and obtain the oxygen content at the end of the converter; the TSO measurement results include the end temperature, end oxygen, and carbon content of the converter, which are automatically obtained by the model, and combined with the model to dynamically calculate the oxygen content to confirm the final molten steel oxygen content.

[0029] S14: The alloy model automatically obtains the test values of the TSC and TSO steel samples of historical heats and corrects the end prediction values of the current heat, specifically including: according to the molten bath carbon content measured by the TSC and TSO of the historical heats that have been obtained, combined with the test carbon content of the steel samples obtained by the TSC and TSO for comparative analysis, confirm the data mean square error, correct the actual composition of the molten steel according to the mean square error formula, and finally calculate the end carbon content according to the dynamic oxygen supply amount.

[0030] Furthermore, the automatic adjustment of the steel grade composition target value in step S4 specifically includes:

[0031] When producing steel grades with the LF route, the alloy model reduces the target value of the molten steel composition at the converter tapping according to the process route and the change value of the molten steel composition of the LF. Because the reducing atmosphere in the LF production process causes the manganese oxide in the slag to be reduced to elemental manganese, resulting in an increase in the manganese content of the molten steel. According to the increase level of manganese in the LF production process, for the molten steel treated by the LF furnace, the manganese addition is reduced during the deoxidation alloying process at the converter tapping to ensure that the final molten steel manganese composition is hit. For example, if the target manganese of the molten steel is required to be 0.80%, and the manganese content of the molten steel increases by 0.03% during the LF furnace treatment of the molten steel, then the target manganese addition during the converter tapping process is 0.77%. In the alloy model, through the set adjustment window, the target manganese content of the molten steel with the LF route can be reduced by 0.03%.

[0032] Further, the dynamic calculation of alloy yield according to the required alloy amount for different steel grades in step S5 specifically includes: adding the yield curves of manganese and silicon components varying with the alloy amount, and the alloy model automatically matching the yield according to the alloy amount to calculate the required alloy amount for the steel grade.

[0033] Further, the alloy is statically calculated according to the converter end point target in step S7, dynamically calculated according to the converter blow stop, and recalculated according to the TSO measurement results and after self-learning and correction of the measurement data. Specifically, it includes:

[0034] S71: After the converter smelting starts, the alloy model preliminarily calculates the alloy according to the target composition of the steel grade. This alloy is calculated based on the hot metal conditions and the predicted end point temperature, carbon content, and residual manganese of the corresponding steel grade (at the end of converter smelting, silicon is completely oxidized, and the residual manganese is calculated by the above formula) to calculate the alloy structure and weight required to reach the target composition of the steel grade.

[0035] For example, if the target composition of the molten steel is: carbon 0.20%, silicon 0.15%, manganese 1.20%, and the alloy model calculates the residual composition of the molten steel at the end of converter smelting as: carbon 0.02%, silicon 0.01%, manganese 0.10%, then the composition of the molten steel to be supplemented is: carbon 0.18%, silicon 0.14%, manganese 1.10%. Assuming the process route is BC, 30 kg of ferrosilicon (with extremely low carbon content, ignoring carbon increase), increasing the silicon content by 0.01%, 30 kg of high-carbon ferromanganese increasing the manganese content by 0.01%, 30 kg of silicomanganese alloy increasing manganese by 0.01%, 150 kg of silicomanganese alloy increasing the silicon component by 0.01%, 300 kg of high-carbon ferromanganese increasing carbon by 0.01%, 1500 kg of silicomanganese alloy increasing the carbon content by 0.01%, 30 kg of carburizer increasing the carbon content by 0.01%. The model preferentially selects silicomanganese alloy according to the alloy cost performance to calculate 2100 kg. At this time, the remaining manganese component is 0.40%. Select 1200 kg of high-carbon ferromanganese. The above alloy increases carbon by 0.054%. The remaining carbon component selects 378 kg of carburizer. If the carburizer upper limit is set not to exceed 300 kg, then the above alloy combination is unreasonable. The alloy model increases the carbon content by 0.10% with the upper limit of 300 kg of carburizer again. The remaining 0.08% of the carbon content is increased by high-carbon ferromanganese and silicomanganese alloy. Then the demand for high-carbon ferromanganese is 2175 kg (continuously calculating the optimal alloy ratio). At this time, according to the manganese content, the demand for silicomanganese alloy is calculated as 1125 kg, and the remaining silicon component uses 195 kg of ferrosilicon. Through the above calculations, the final alloy types and quantities are obtained: 195 kg of ferrosilicon, 2175 kg of high-carbon ferromanganese, 1125 kg of silicomanganese alloy, and 300 kg of carburizer.

[0036] S72: Recalculate the alloy according to the dynamic calculation results after TSC measurement.

[0037] S73: Recalculate the alloy again according to the end point prediction value after the converter end point blow stop.

[0038] S74: After the TSO measurement, the alloy model recalculates the alloy according to the TSO measurement results combined with self-learning correction.

[0039] Furthermore, in step S9, the alloy calculation cost is optimized, specifically including: the alloy model calculates the alloy corresponding to a single component according to the alloy composition and price first, and the remaining components of the molten steel composition that have not reached the target brought by this alloy continue to calculate other alloys until all alloy calculations are completed.

[0040] The beneficial effects of the present invention are as follows: This alloy model fully considers the influence of factors such as the amount of molten steel, different process routes, the requirements of multiple steel grades and alloys, the properties of alloy use, the characteristics of alloy yield, the residual components at the end of the converter, and the combination of low-cost alloys on the control of the target composition of molten steel. The alloy model has the advantages of high hit rate, wide application range, simple operation, and being conducive to popularization. The present invention changes the traditional deoxidation alloying method for tapping in the converter, which is different from the narrow application scope of the traditional alloy model, and is applied to the continuous production organization of the current steel mill, with outstanding alloy cost reduction effect and greatly reducing the labor intensity of operators.

[0041] Other advantages, objectives, and features of the present invention will be described to some extent in the subsequent specification, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the following specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be described in detail preferably with reference to the accompanying drawings, where:

[0043] Figure 1 is the flow chart of the low-cost alloy calculation method for converters using all steel grades of the present invention;

[0044] Figure 2 is the schematic diagram of the alloy model interface of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0046] Among them, the attached drawings are only for illustrative purposes, showing only schematic diagrams rather than physical drawings, and should not be construed as a limitation on the present invention; in order to better illustrate the embodiments of the present invention, some components in the attached drawings will be omitted, enlarged or reduced, which does not represent the size of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the attached drawings may be omitted.

[0047] In the attached drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "rear", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the attached drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the attached drawings are only for illustrative purposes and should not be construed as a limitation on the present invention. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0048] As Figure 1-2 shown, the present invention provides a converter low-cost alloy calculation method applicable to all steel grades, including the following steps:

[0049] Automatically obtain the amount of hot metal and scrap charged into the converter, calculate the amount of molten steel tapped from the converter according to the recovery rates of different metal materials, consider the maintenance of basic data, limit the range of the converter charge and ensure the calculation of the amount of molten steel tapped with the minimum charge; after the converter smelting starts, the alloy model automatically obtains the amount of hot metal and scrap in the current heat, and calculates the amount of molten steel tapped from the converter according to the recovery rate. The recovery rates are shown in Table 1:

[0050] Table 1

[0051] Name Unit Recovery Rate Hot Metal as Main Raw Material kg 0.93 Iron Block as Main Raw Material kg 0.93 Steel Edge as Main Raw Material kg 0.95 Heavy Scrap as Main Raw Material kg 0.95 Steel Slag for Steelmaking as Main Raw Material kg 0.65

[0052] To stabilize the calculation accuracy of the alloy model, an automatic correction mechanism for the charge error is added. Set the value of the fixed charge of the converter and the range value of the hot metal. When the scrap information is missing in the charge, the model automatically calculates the amount of scrap according to the predetermined charge, and at the same time predicts the amount of molten steel tapped, reducing the impact of the calculation error of the amount of molten steel tapped on the accurate calculation of the alloy. The specific formula for automatically calculating the amount of scrap according to the predetermined charge is as follows:

[0053] Amount of scrap = Predetermined total charge - Weight of hot metal - Weight of scrap added in the ladle

[0054] The predetermined total charge can be adjusted according to the actual demand of the current production of the converter. Taking the weight of hot metal and the amount of scrap added in the ladle as fixed quantities and the amount of scrap in the scrap bucket as a variable quantity, when the model automatically obtains the weight of hot metal and the amount of scrap added in the ladle, if the weight of the scrap bucket is missing, then according to the error correction mechanism, the weight of the scrap charged into the scrap bucket is automatically calculated according to the preset total charge. However, when neither the amount of hot metal nor the amount of scrap added in the ladle can be obtained, the model will not be able to automatically calculate the amount of scrap in the scrap bucket, and only calculate the amount of molten steel in the current heat according to the charging system of the previous heat.

[0055] The specific steps for predicting the amount of molten steel are as follows: Calculate the amount of molten steel in the current heat according to the weight of hot metal, the types and weights of scrap added in the ladle, and the types and weights of scrap added in the scrap bucket, based on the recovery rates of the corresponding raw materials.

[0056] Automatically obtain the TSC and TSO measurement values of the converter and the results of the in-process molten steel analysis, and combine dynamic calculation and self-learning to judge the oxygen content at the end of the converter and the residual manganese and carbon contents at the end of the converter; the calculation of residual manganese is carried out using a regression equation, and the parameters of the regression equation are dynamically corrected according to the analysis results of the samples at the end of the converter to ensure the accuracy of the residual manganese at the end, as follows:

[0057] Residual manganese at the end of the converter = 0.7926 + 0.1862 * manganese content in hot metal - 0.000066 * oxygen at the end of the converter - 0.000432 * temperature at the end of the converter

[0058] The data at the end of the converter is, on the one hand, measured by the sublance TSO; on the other hand, it is dynamically calculated. When there is sublance TSO data, the optimized sublance data is used to calculate the residual manganese at the end of the converter. When there is no TSO data, the data at the end of the converter is dynamically calculated according to the TSC data; if neither the sublance TSC nor TSO data is available, the historical data is compared to calculate the residual manganese at the end.

[0059] The coefficient of the regression equation for calculating the residual manganese in the converter is automatically calculated every 10 - 20 heats of valid data, and the calculated coefficient is automatically assigned to the formula. Whether to use the coefficient automatic calculation for correction can be manually selected.

[0060] After the TSC measurement in the converter, the dynamic smelting process begins. The model predicts the final oxygen content, residual manganese, and residual carbon in the converter based on the target steel grade composition and the TSC measurement results. During the converter smelting process, the specific composition range and target composition of the steel grade produced in this furnace are first obtained, and the target temperature and composition at the end of the converter are calculated based on the process route and the target composition. When the TSC measures the bath temperature and carbon content, the actual temperature and composition reached at the end are dynamically calculated based on the supplied oxygen amount according to the previously calculated target temperature and composition. When the process route is BC or BRC, the model, based on the TSC results and with the priority of hitting the temperature, tries to ensure that the carbon content is met. This principle is mainly achieved through the calculated dynamic oxygen supply amount. When the process route is BLC or BLRC, the carbon content is given priority to be met under the condition of ensuring the lowest tapping temperature (which can be set according to requirements). According to the hitting principles for the aforementioned different process routes and combined with the actual dynamic oxygen supply amount, the final oxygen content is calculated, and at the same time, the final temperature and final oxygen, combined with the hot metal conditions, are used to calculate the final residual manganese content.

[0061] After the TSO measurement, the final residual manganese and carbon are predicted again based on the TSO measurement results, and the oxygen content at the end of the converter is obtained. The alloy model can automatically obtain the test values of the TSC and TSO steel samples of historical heats and correct the predicted values at the end of the current heat. Specifically, the model compares and analyzes the measured bath carbon content of the TSC and TSO of the historical heats that have been obtained, combined with the test carbon content of the steel samples obtained through the TSC and TSO, to confirm the data mean square error, and corrects the actual composition of the molten steel according to the mean square error formula. Finally, the final carbon content is calculated based on the dynamic oxygen supply amount.

[0062] The alloy model sets the alloy type requirements for general steel grades and special steel grades to adapt to the alloy calculations required for all steel grades. Since there are many alloy types, special alloys are required for the smelting of individual steel grades, but the introduction of special alloys will cause confusion in the alloy model's alloy calculations. For example, when carbon is adjusted at the end of the converter for 45# steel, manganese-carbon balls are required. Manganese-carbon balls contain carbon and manganese, and are only used in the smelting of this steel grade. If this alloy is included in the general alloy calculations, there will be confusion in the calculations with carburants and ferromanganese alloys during carbon and manganese adjustment, resulting in the alloy model having no practical guiding significance. Therefore, an alloy model calculation section for special steel grades is added. When producing this steel grade, the alloy model automatically subtracts the fixed alloy addition and then calculates the remaining alloys, enabling the alloy model to calculate steel grades of any composition.

[0063] Automatically adjust the target values of steel grades according to different process routes. For the production of steel grades in the BLC and BLRC routes, due to the influence of the reducing atmosphere during the LF treatment process, the molten steel will experience phenomena such as manganese return, silicon return, and carbon increase. Add an automatic adjustment program for the target components of steel grades in different process routes. When producing steel grades in the LF route, the alloy model reduces the target value of the molten steel composition at the converter tapping according to the process route and the change value of the molten steel composition in the LF, ensuring that the molten steel composition is hit after LF treatment and reducing the alloy cost. Due to the reducing atmosphere in the LF production process, the manganese oxide in the slag is reduced to elemental manganese, resulting in an increase in the manganese content of the molten steel. According to the increase level of manganese during the LF production process, set the molten steel treated by the LF furnace to reduce the manganese addition during the deoxidation alloying process at the converter tapping to ensure that the final manganese composition of the molten steel is hit. For example, if the target manganese of the molten steel is required to be 0.80%, and the manganese content of the molten steel increases by 0.03% during the LF furnace treatment of the molten steel, then the target manganese addition during the converter tapping process is 0.77%. In the alloy model, through the set adjustment window, subtract 0.03% from the target manganese content of the molten steel in the LF route.

[0064] Dynamically calculate the alloy yield according to the required alloy amount of different steel grades. The higher the target composition of the molten steel, the higher the alloy yield. To ensure the composition hit rate of steel grades with different alloy amount requirements, add the yield curves of manganese and silicon components varying with the alloy amount. The alloy model automatically matches the yield according to the alloy amount and calculates the required alloy amount for the steel grade.

[0065] Set the upper limit of the carburizer according to the usage characteristics of the carburizer. During the deoxidation alloying stage at the converter tapping, when the usage of the carburizer reaches a certain amount, the yield becomes unstable, and it also affects the calculation of other alloys. According to the usage properties of the carburizer, set the upper limit of the carburizer usage. When the required carbon addition exceeds the upper limit of the carburizer, use alloy for carbon addition.

[0066] Static calculation of the alloy according to the converter end point target. This alloy is calculated based on the molten iron conditions, the predicted end point temperature, carbon content, and residual manganese of the corresponding steel grade (at the end of the converter smelting, silicon is completely oxidized, and the residual manganese is calculated by the above formula) to calculate the alloy structure and weight required to reach the target composition of the steel grade.

[0067] Calculate the alloy dynamically according to the converter's blow stop, and recalculate the alloy after self-learning and correction of the measurement data based on the TSO measurement results. After the converter smelting starts, the alloy model initially calculates the alloy according to the target composition of the steel grade. This alloy is calculated based on the hot metal conditions and the predicted end-point temperature, carbon content, and residual manganese of the corresponding steel grade (at the end of converter smelting, silicon is completely oxidized, and the residual manganese is calculated by the above formula) to calculate the alloy structure and weight required to reach the target composition of the steel grade. For example, if the target composition of the molten steel is: carbon 0.20%, silicon 0.15%, manganese 1.20%, and the alloy model calculates the residual composition of the molten steel at the end of converter smelting as: carbon 0.02%, silicon 0.01%, manganese 0.10%, then the molten steel composition that needs to be supplemented is: carbon 0.18%, silicon 0.14%, manganese 1.10%. Assuming the process route is BC, 30 kg of ferrosilicon (with a very low carbon content, carbon increase is negligible) increases the silicon content by 0.01%, 30 kg of high-carbon ferromanganese increases the manganese content by 0.01%, 30 kg of silicomanganese alloy increases manganese by 0.01%, 150 kg of silicomanganese alloy increases the silicon component by 0.01%, 300 kg of high-carbon ferromanganese increases carbon by 0.01%, 1500 kg of silicomanganese alloy increases the carbon content by 0.01%, 30 kg of carburizer increases the carbon content by 0.01%. The model preferentially selects silicomanganese alloy according to the alloy cost performance and calculates 2100 kg. At this time, the remaining manganese component is 0.40%. Select 1200 kg of high-carbon ferromanganese. The above alloy increases carbon by 0.054%. For the remaining carbon component, select 378 kg of carburizer. If the upper limit of the carburizer is set not to exceed 300 kg, then the above alloy combination is unreasonable. The alloy model increases the carbon content by 0.10% with the upper limit of 300 kg of carburizer again. The remaining 0.08% of the carbon content is increased by high-carbon ferromanganese and silicomanganese alloy. Then the demand for high-carbon ferromanganese is 2175 kg (continuously calculate the optimal alloy ratio through cycles). At this time, according to the manganese content, the demand for silicomanganese alloy is calculated as 1125 kg, and the remaining silicon component uses 195 kg of ferrosilicon. Through the above calculations, the final alloy types and quantities are obtained: 195 kg of ferrosilicon, 2175 kg of high-carbon ferromanganese, 1125 kg of silicomanganese alloy, and 300 kg of carburizer.

[0068] After the TSC measurement, recalculate the alloy according to the dynamic calculation results. After the converter stops blowing at the end point, recalculate the alloy according to the end-point prediction value. When the TSO measurement is carried out, the alloy model recalculates the alloy according to the TSO measurement results combined with self-learning correction to ensure the continuity and accuracy of the alloy calculation.

[0069] The alloy model sets up a database of alloy types, compositions, and unit prices, and a database of the target compositions of steel grades, and automatically obtains the steel grade and the target value of composition control for the current furnace smelting. After the converter smelting starts, the alloy model automatically obtains the steel grade and the target composition of the current furnace smelting, which is convenient for calculating the alloy in a timely and accurate manner. The alloy model sets up an alloy information database to guide the low-cost calculation of the alloy model. The database of the target compositions of steel grades is used to guide the alloy model to calculate the alloy according to the target composition of the steel grade.

[0070] The alloy is automatically calculated and automatically downloaded to the primary machine for alloy weighing. Data is transmitted between the alloy model and each stage of converter smelting. The alloy model automatically triggers calculations according to different smelting stages. After each alloy calculation, the calculation results are automatically downloaded to the primary machine to facilitate the weighing preparation of alloys in different stages.

[0071] The alloy calculation cost is optimized. The alloy model first calculates the alloy corresponding to a single component based on the alloy composition and price. For the remaining components in the molten steel composition that have not reached the target after adding this alloy, other alloys are continued to be calculated until all alloy calculations are completed. For example, for a steel grade with a target carbon content of 0.22%, silicon content of 0.15%, and manganese content of 0.60%, and the residual carbon content of 0.07%, residual silicon content of 0.01%, and residual manganese content of 0.10% at the end of converter smelting, the alloy model first allocates silicon using the silicomanganese alloy with the lowest price. Subsequently, ferromanganese is calculated based on the remaining manganese content required. For the remaining carbon after considering the increase in carbon content by the alloying agent, a carburizer is calculated. When the calculated carburizer exceeds the upper limit value, except for the carbon increased by the upper limit carburizer, the remaining carbon is allocated by ferromanganese. After deducting the manganese allocated by ferromanganese, the remaining manganese is used to calculate the amount of silicomanganese. After deducting the silicon increased by silicomanganese, the remaining silicon component is used to calculate ferrosilicon until all alloys are calculated at the lowest alloy cost.

[0072] Through the application of this alloy model for the calculation of alloys for all steel grades, the hit rates of conventional elements are as follows: silicon hit rate ≥ 98%, manganese hit rate ≥ 95%, and carbon hit rate ≥ 92%. The average alloy cost reduction reaches 1.5 yuan / t·steel, and the cost reduction effect is obvious.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not restrictive. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the present technical solution, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A converter low-cost alloy calculation method applicable to all steel grades, characterized in that: It includes the following steps: S1: Automatically obtain the hot metal and scrap charge amounts of the converter, calculate the tapping amount of the converter according to the yield rates of different metal materials, consider the maintenance of basic data, limit the converter charge amount range, and ensure the tapping amount is calculated based on the minimum charge amount; S2: Automatically obtain the TSC and TSO measurement values of the converter and the process molten steel test results, and combine dynamic calculation and self-learning to judge the oxygen content at the end of the converter and the residual manganese and carbon contents at the end of the converter; S3: The alloy model sets the alloy type requirements for general steel grades and special steel grades, and adapts to the alloy calculation required for all steel grades; S4: Automatically adjust the target values of the steel grade components according to different process paths; S5: Dynamically calculate the alloy yield rate according to the alloy amounts required for different steel grades; S6: Set the upper limit of the recarburizer according to the usage characteristics of the recarburizer, and use alloy for carbon addition when the required carbon addition amount exceeds the upper limit of the recarburizer; S7: Static calculation of the alloy according to the converter end point target, dynamic calculation of the alloy according to the converter blow end, and recalculation of the alloy according to the TSO measurement result and after self-learning correction of the measurement data; S8: The alloy model sets the alloy type, composition and unit price database to guide the low-cost calculation of the alloy model; set the steel grade target composition database to guide the alloy model to calculate the alloy according to the steel grade target composition; the alloy model also automatically obtains the steel grade being smelted in the current heat and the component control target value; S9: The alloy is automatically calculated and automatically loaded to the first-level machine for alloy weighing, and the alloy calculation cost is the most optimal; The step of automatically obtaining the TSC and TSO measurement values of the converter and the process molten steel test results in step S2, and combining dynamic calculation and self-learning to judge the oxygen content at the end of the converter and the residual manganese and carbon contents at the end of the converter specifically includes: S21: Calculate the residual manganese content at the end of the converter using a regression equation, and the parameters of the regression equation are dynamically corrected according to the test results of the converter end point samples to ensure the hitting of the residual manganese at the end point. Specifically as follows: Residual manganese at the end of the converter = 0.7926 + 0.1862 * hot metal manganese content - 0.000066 * oxygen at the end of the converter - 0.000432 * temperature at the end of the converter The converter end point data is obtained through TSO measurement by the sublance on the one hand, and the following dynamic calculation is carried out on the other hand: when there is sublance TSO data, the optimized sublance data is used to calculate the residual manganese at the end of the converter; when there is no TSO data, the converter end point data is dynamically calculated according to the TSC data; if there is no sublance TSC and TSO data, the historical data is compared to calculate the residual manganese at the end point; the coefficients are automatically calculated through the regression equation for every 10 - 20 heats of valid data, and the calculated coefficients are automatically assigned to the converter residual manganese calculation formula, and it is selected whether to use the coefficients for automatic calculation and correction; S22: After the TSC of the converter is measured, it enters dynamic smelting, and the alloy model predicts the oxygen content, residual manganese and residual carbon at the end of the converter according to the steel grade component target and the TSC measurement result; During the converter smelting process, first obtain the specific composition range and target composition of the steel grade produced by this furnace, and calculate the target temperature and composition at the end of the converter according to the process route and target composition; after the TSC measures the molten bath temperature and carbon content, according to the calculated target temperature and composition, dynamically calculate the actually hit temperature and composition at the end according to the oxygen supply amount; when the process route is BC or BRC, the model, based on the TSC results and with the priority of hitting the temperature, tries to ensure carbon hitting through the calculated dynamic oxygen supply amount; when the process route is BLC or BLRC, prioritize carbon hitting under the condition of ensuring the lowest tapping temperature; according to the hitting principles of different process routes, combine the actual dynamic oxygen supply amount to calculate the oxygen content at the end, and at the same time, the calculated end temperature and end oxygen, combined with the hot metal conditions, calculate the residual manganese content at the end. S23: After the TSO measurement, predict the residual manganese and carbon at the end again according to the TSO measurement results and obtain the oxygen content at the end of the converter; the TSO measurement results include the temperature at the end of the converter, the oxygen at the end, and the carbon content, which are automatically obtained by the model, and combine the model to dynamically calculate the oxygen content to confirm the oxygen content of the final molten steel. S24: The alloy model automatically obtains the test values of the TSC and TSO steel samples of historical heats and corrects the end point prediction values of the current heat, specifically including: according to the measured molten bath carbon content of the TSC and TSO of the historical heats that have been obtained, combine the test carbon content of the steel samples obtained through the TSC and TSO for comparative analysis, confirm the data square difference, correct the actual composition of the molten steel according to the square difference formula, and finally calculate the carbon content at the end according to the dynamic oxygen supply amount. The specific calculation of the alloy recovery rate according to the alloy amount required for different steel grades in step S5 includes: adding the recovery rate curves of manganese and silicon components varying with the alloy amount, and the alloy model automatically matches the recovery rate according to the alloy amount to calculate the alloy amount required for the steel grade. The calculation of the alloy according to the static target at the end of the converter, the dynamic calculation of the alloy according to the converter blow stop in step S7, and the recalculation of the alloy according to the TSO measurement results and after self-learning correction of the measurement data specifically include: S71: After the converter smelting starts, the alloy model initially calculates the alloy according to the target composition of the steel grade. This alloy calculates the alloy structure and weight required to reach the target composition of the steel grade based on the hot metal conditions and the predicted end temperature, carbon content, and residual manganese of the corresponding steel grade. S72: Recalculate the alloy according to the dynamic calculation results after the TSC measurement. S73: Recalculate the alloy according to the end point prediction value after the converter stops blowing at the end. S74: When the TSO measurement is carried out, the alloy model recalculates the alloy according to the TSO measurement results combined with self-learning correction.

2. The converter low-cost alloy calculation method applicable to all steel grades according to claim 1, characterized in that: The automatic acquisition of the hot metal and scrap steel amounts charged into the converter in step S1, calculate the tapping amount of the converter according to the recovery rates of different metal materials, considering the basic data maintenance, limit the charging amount range of the converter and ensure the tapping amount is calculated based on the minimum charging amount, specifically including: S11: After the converter smelting starts, the alloy model automatically obtains the amount of hot metal and scrap steel in the current heat, and calculates the tapping amount of the converter according to the yield rate. The yield rates of the main raw materials, hot metal and iron lumps, are 0.93, the yield rates of the main raw materials, steel edges and heavy scrap, are 0.95, and the yield rate of the main raw material, steelmaking slag steel, is 0.

65. S12: Introduce an automatic correction mechanism for the charging amount error, set the value of the fixed charging amount of the converter and the hot metal range value. When the scrap steel information is missing in the charging amount, the model automatically calculates the scrap steel amount according to the predetermined charging amount and predicts the tapping amount at the same time. The automatic calculation of the scrap steel amount according to the predetermined charging amount specifically includes: Scrap steel amount = Predetermined total charging amount - Hot metal weight - Scrap steel weight added to the ladle Among them, the predetermined total charging amount is adjusted according to the actual demand of the current production of the converter. Taking the hot metal weight and the scrap steel amount added to the ladle as fixed quantities and the scrap steel amount in the scrap steel bucket as a variable, after automatically obtaining the hot metal weight and the scrap steel amount added to the ladle, if the weight of the scrap steel bucket is missing, according to the error correction mechanism, the scrap steel weight loaded into the scrap steel bucket is automatically calculated according to the preset total charging amount; but when both the hot metal amount and the scrap steel amount added to the ladle cannot be obtained, the scrap steel amount in the scrap steel bucket cannot be automatically calculated, and only the steel water amount of the current heat is calculated according to the charging system of the previous heat. The specific steps for predicting the tapping amount are as follows: According to the hot metal weight, the types and weights of the scrap steel added to the ladle, and the types and weights of the scrap steel added to the scrap steel bucket, calculate the tapping amount of the current heat according to the yield rates of the corresponding raw materials.

3. The method for calculating low-cost alloys in a converter applicable to all steel grades according to claim 1, characterized in that: The automatic adjustment of the steel grade composition target value according to different process paths described in step S4 specifically includes: When producing steel grades on the LF path, the alloy model reduces the target value of the converter tapping steel water composition according to the process path and the change value of the steel water composition of LF. According to the increase level of manganese during the LF production process, the steel water treated by the LF furnace is set, and the manganese addition in the converter tapping deoxidation alloying process is reduced to ensure that the final steel water manganese composition is met.

4. The converter low-cost alloy calculation method applicable to all steel grades according to claim 1, characterized in that: The alloy calculation cost is optimal in step S9, specifically including: The alloy model first calculates the alloy corresponding to a single component according to the alloy composition and price. The remaining unmet target components brought by this alloy to the steel water composition continue to calculate other alloys until all alloys are calculated.

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