A converter lean collaborative fast rhythm smelting and low iron consumption production control method

Abstract

The application discloses a converter lean and fast rhythm smelting and low iron consumption production control method, and belongs to the technical field of converter steelmaking production, and the method comprises the following steps: accurate calibration of a weighing system; low iron consumption charging material structure optimization; oxygen lance and blowing process optimization; fast rhythm process connection; refining-continuous casting collaborative control; and iron consumption-full iron material model management and control. Through the above six core measures, the problems of long traditional converter smelting cycle, high iron consumption, poor collaboration, and out-of-control full iron material can be solved. The molten iron unit consumption of a 180t converter can be reduced to 855kg / t, the smelting cycle can be shortened to 29.5min, the monthly output can be increased by 46800 tons, the method has the advantages of high index, high capacity, low cost, easy popularization and the like, and is suitable for large and medium-sized converter efficient and low-cost production.

Description

Technical Field

[0001] This invention belongs to the field of converter steelmaking production technology, specifically relating to a method for lean collaborative fast-paced smelting and low iron consumption production control in converters, which is particularly suitable for efficient, low-consumption, and collaborative production in 180t converters. Background Technology

[0002] As a core process in steel enterprises, the efficiency of converter steelmaking directly affects overall production efficiency. However, a series of prominent problems generally exist in the traditional converter smelting process, including excessively long smelting cycles, high iron consumption, poor coordination among various production stages, insufficient material weighing accuracy, unreasonable configuration of materials entering the furnace, lengthy waiting times between processes, and difficulty in matching the rhythm of converter and continuous casting. These factors seriously restrict production optimization and cost control.

[0003] Under current technological conditions, taking a 180-ton converter as an example, the iron consumption per ton of steel is as high as 919 kg, the scrap steel ratio is only 19.95%, and the smelting cycle is as long as 30 to 31.5 minutes. This slow production pace and high cost make it difficult for enterprises to achieve the production goal of "increasing capacity and reducing iron consumption," which not only affects capacity release but also increases resource consumption and environmental burden. Specifically, high iron consumption per ton of steel leads to strong dependence on raw materials, while the low scrap steel ratio restricts resource recycling, further exacerbating production cost pressures.

[0004] In attempts to reduce iron consumption per unit volume, a series of chain reactions often occur, such as an increase in overall iron content instead of a decrease, insufficient heat supply, frequent furnace splashing, higher equipment failure rates, and production disruptions. These defects not only affect smelting stability but also increase operational risks and maintenance costs, creating a conflict between production pace and iron consumption control. Ultimately, traditional methods cannot achieve synergistic optimization between fast-paced production and low iron consumption goals, leaving steel companies facing continuous challenges in improving efficiency and reducing energy consumption. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for controlling lean collaborative fast-paced smelting and low iron consumption production in converters. By improving weighing accuracy, optimizing material structure, optimizing blowing parameters, accelerating process connections, coordinating refining and continuous casting, and managing data models, the method aims to reduce iron consumption, shorten smelting cycles, and increase production capacity.

[0006] A method for lean collaborative fast-paced smelting and low-iron-consumption production control in converters includes: Accurate calibration of the weighing system: Regularly calibrate the weighing systems for molten iron, scrap steel, and molten steel ladles to control weighing errors and implement the process of mixing iron into a single bag. Low-iron-consumption furnace material structure optimization: Specific weights of scrap steel, briquettes and auxiliary materials are configured in the converter scrap hopper and molten iron ladle, with a total scrap steel amount of not less than 54t. Steel slag is added during the blowing process, and clinker is used instead of raw materials. Oxygen lance and blowing process optimization: Using oxygen lances with specific parameters to control the lance position during the initial blowing, intermediate blowing, and carbon extraction stages, and maintaining a specific oxygen supply flow rate; Fast-paced process connection: Positions are in place before the blowing process ends, so that steel can be produced immediately upon lifting the lance, and a material early warning and equipment inspection mechanism is established to reduce process waiting time; Refining-continuous casting coordinated control: controlling the refining table temperature and composition qualification rate, and optimizing the performance of continuous casting roll gap and protective slag; Iron consumption-total iron material model management: Establish a dynamic data model to track and control the unit consumption of molten iron and the total iron material index in real time.

[0007] Preferably, the calibration frequency is twice a week, the weighing error is no greater than ±0.5%, and the converter loading accuracy rate is no less than 85%.

[0008] Preferably, the materials loaded into the converter scrap hopper include: 27t of purchased scrap steel, 6t-7t of compressed briquettes, and 6t-7t of magnetically separated bottom slag.

[0009] Preferably, the materials added to the molten iron ladle include: 10 briquettes and 1 shovel of crushed material, with a total weight of 13t; 4t of steel slag is added during the blowing process.

[0010] Preferably, the 27t of purchased scrap steel includes 5t to 6t of iron blocks.

[0011] Preferably, the oxygen lance parameters are: throat diameter of φ47.5mm, outlet diameter of φ63mm, center angle of 12.5°, and Mach number of 2.05; the lance position control is: 0.8m for initial blowing, 1.4m to 1.6m for intermediate blowing, and 1.0m for carbon removal; and the oxygen supply flow rate is 43500 Nm³ / h.

[0012] Preferably, the time for the work station to be in place is 2 minutes before the end of the blowing process, and the waiting time for the process is reduced by 2 to 3 minutes.

[0013] Preferably, the refining temperature is 1565.5℃, the component qualification rate is not less than 85%, and the continuous casting speed is not less than 1.35m / min.

[0014] Preferably, iron consumption is controlled at 850 kg / t to 860 kg / t, and total iron content is stabilized at 1061 kg / t to 1067 kg / t.

[0015] Preferably, the smelting cycle is no more than 29.5 minutes and the iron consumption per unit is no more than 855 kg / t.

[0016] The advantages and technical effects of this invention are as follows: This invention employs a precise weighing system, conducting systematic calibration of the molten iron, scrap steel, and molten steel ladle weighing systems twice a week to ensure each weighing device is in optimal working condition. This strictly controls the weighing error to ≤±0.5%, effectively improving the accuracy of raw material proportioning. The converter loading accuracy rate has significantly increased from 70% to over 85%. Simultaneously, it implements a one-bag clean iron-mixing process, with the iron-discharging station discharging iron quantitatively based on the amount of scrap steel, achieving precise matching of molten iron and scrap steel and reducing resource waste.

[0017] This invention optimizes the material structure for low-iron-consumption furnace feed. 27t of purchased scrap steel (including 5-6t of iron blocks), 6-7t of compressed briquettes, and 6-7t of magnetically separated bottom slag are added to the converter scrap hopper. Ten compressed briquettes and one shovelful of crushed material are added to the molten iron ladle, totaling 13t. The total amount of scrap steel fed into the furnace is ≥54t. An additional 4t of steel slag is added during the blowing process to balance the chemical composition within the furnace. Clinker is used instead of raw materials, and lightly calcined dolomite is used as an auxiliary material to ensure stable heat input and improve smelting efficiency.

[0018] This invention optimizes the oxygen lance and blowing process. Regarding the oxygen lance structure: the throat diameter is adjusted from φ48.5mm to φ47.5mm, the outlet diameter from φ63.5mm to φ63mm, the center angle is optimized from 13° to 12.5°, and the Mach number is increased from 2.02 to 2.05 to enhance the penetration and stirring effect of the oxygen jet. The blowing lance positions are set as follows: 0.8m for initial blowing, 1.4–1.6m for intermediate blowing, and 1.0m for carbon extraction. The oxygen supply flow rate is increased to 43500 Nm³ / h, and the oxygen supply time is shortened by more than 0.6 minutes, effectively reducing low-temperature splashing and improving blowing stability.

[0019] This invention achieves rapid process control by arranging personnel to be in position 2 minutes before the end of blowing, enabling steel to be produced immediately upon lifting the lance, reducing waiting time for samples and personnel by 2-3 minutes, and accelerating the production pace; it implements a shift-by-shift equipment inspection system, strengthens the maintenance of key equipment such as auxiliary lances, ladle cars, and oxygen lances, and reduces the risk of unplanned downtime; it establishes a material storage early warning mechanism to monitor the inventory of auxiliary materials such as lime in real time, prevent supply interruptions, and optimizes crane scheduling to eliminate the phenomenon of equipment waiting for people, materials, and ladles, ensuring a smooth production process.

[0020] This invention accelerates refining and continuous casting in a coordinated manner. The refining platform temperature is reduced from 1570℃ to 1565.5℃, and the purity of molten steel is improved through precise temperature control, increasing the qualified rate of molten steel composition from 78% to 85% and the qualified rate of sulfur from 79% to 88%. The continuous casting process is subject to weekly maintenance, and the roll gap is measured regularly to maintain equipment precision and ensure billet quality. The physical and chemical properties of the protective slag are optimized to improve lubrication and heat insulation effects, achieving a casting speed of ≥1.35m / min. Standardized operation cards are developed for key positions to standardize operating procedures and improve continuous casting efficiency and production consistency.

[0021] This invention manages iron consumption and total iron content through a data model, establishing a dynamic correlation model between iron consumption and total iron content. It tracks key indicators such as iron consumption per unit volume, total iron content, steel output, and scrap steel ratio in real time, achieving data-driven refined management. Iron consumption is controlled at 850 kg / t to 860 kg / t, and total iron content is stabilized at 1061 kg / t to 1067 kg / t. Through model-based early warning and adjustment, indicator omissions are eliminated, ensuring production economy and stability. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] A method for lean collaborative fast-paced smelting and low-iron-consumption production control in converters mainly includes the following steps: (1) Accurate calibration of the weighing system: The weighing system of molten iron, scrap steel and molten steel ladle is calibrated twice a week. The weighing error is ≤ ±0.5%, the converter loading accuracy rate is ≥ 85%, and the process of one ladle of clean iron is implemented. (2) Optimization of material structure for low iron consumption in furnace: 27t of purchased scrap steel (including 5t-6t of iron blocks) + 6t-7t of briquette + 6t-7t of magnetic separation bottom slag are loaded into the scrap steel hopper of the converter. 10 briquettes + 1 shovel of crushed material are added to the molten iron ladle. The total weight is 13t. The total amount of scrap steel is ≥54t. 4t of steel slag is added during the blowing process to replace raw materials with clinker. (3) Optimization of oxygen lance and blowing process: The oxygen lance throat is φ47.5mm, the outlet diameter is φ63mm, the center angle is 12.5°, and the Mach number is 2.05; the opening blowing lance position is 0.8m, the middle blowing lance position is 1.4m~1.6m, the carbon pulling lance position is 1.0m, and the oxygen supply flow rate is 43500Nm³ / h; (4) Fast-paced process connection: the station is in place 2 minutes before the end of the blowing process, and the steel is discharged immediately after the gun is lifted, reducing the waiting time by 2 to 3 minutes; perform equipment inspection, establish material early warning, and optimize production scheduling; (5) Refining-continuous casting coordinated control: refining table temperature 1565.5℃, composition qualification rate ≥85%; continuous casting weekly maintenance, roll gap measurement, optimization of protective slag, casting speed ≥1.35m / min; (6) Iron consumption - total iron material model control: Establish a dynamic data model, control iron consumption at 850kg / t to 860kg / t, and stabilize total iron material at 1061kg / t to 1067kg / t.

[0024] The smelting cycle is ≤29.5min, and the iron consumption is ≤855kg / t.

[0025] The continuous casting speed is stable at ≥1.35m / min.

[0026] Taking our company's 180t converter as an example: 1. The weighing system shall be calibrated twice a week, with an accuracy rate of ≥85%, and one bag of iron shall be used for mixing. 2. The materials fed into the furnace are configured according to 54t of scrap steel bucket and 13t of molten iron ladle, and 4t of steel slag is added during the blowing process; 3. An optimized oxygen lance is used, with the lance position at 0.8m and an oxygen supply flow rate of 43,500 Nm³ / h; 4. By performing the steel extraction process, the waiting time is reduced by 2-3 minutes; 5. Refining platform temperature: 1565.5℃; continuous casting speed: ≥1.35m / min; 6. The iron consumption and total iron content are adjusted in real time according to the iron consumption-total iron content model, with iron consumption stable at 855 kg / t and total iron content at 1066.5 kg / t.

[0027] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall fall within the scope of the technical solution of the present invention.

Claims

1. A method for lean collaborative fast-paced smelting and low-iron-consumption production control in a converter, characterized in that, include: Accurate calibration of the weighing system: Regularly calibrate the weighing systems for molten iron, scrap steel, and molten steel ladles to control weighing errors and implement the process of mixing iron into a single bag. Low-iron-consumption furnace material structure optimization: Specific weights of scrap steel, briquettes and auxiliary materials are configured in the converter scrap hopper and molten iron ladle, with a total scrap steel amount of not less than 54t. Steel slag is added during the blowing process, and clinker is used instead of raw materials. Oxygen lance and blowing process optimization: Using oxygen lances with specific parameters to control the lance position during the initial blowing, intermediate blowing, and carbon extraction stages, and maintaining a specific oxygen supply flow rate; Fast-paced process connection: Positions are in place before the blowing process ends, so that steel can be produced immediately upon lifting the lance, and a material early warning and equipment inspection mechanism is established to reduce process waiting time; Refining-continuous casting coordinated control: controlling the refining table temperature and composition qualification rate, and optimizing the performance of continuous casting roll gap and protective slag; Iron consumption-total iron material model management: Establish a dynamic data model to track and control the unit consumption of molten iron and the total iron material index in real time.

2. The converter lean collaborative fast-paced smelting and low iron consumption production control method according to claim 1, characterized in that, The calibration frequency is twice a week, the weighing error is no greater than ±0.5%, and the converter loading accuracy rate is no less than 85%.

3. The converter lean collaborative fast-paced smelting and low iron consumption production control method according to claim 1, characterized in that, The materials loaded into the converter scrap hopper include: 27t of purchased scrap steel, 6-7t of compressed briquettes, and 6-7t of magnetically separated bottom slag.

4. The converter lean collaborative fast-paced smelting and low iron consumption production control method according to claim 3, characterized in that, The materials added to the molten iron ladle include: 10 briquettes and 1 shovel of crushed material, with a total weight of 13t; 4t of steel slag is added during the blowing process.

5. The converter lean collaborative fast-paced smelting and low iron consumption production control method according to claim 4, characterized in that, 27 tons of scrap steel were purchased, including 5 to 6 tons of iron blocks.

6. The converter lean collaborative fast-paced smelting and low iron consumption production control method according to claim 1, characterized in that, The oxygen lance parameters are as follows: throat diameter φ47.5mm, outlet diameter φ63mm, center angle 12.5°, Mach number 2.05; lance position control is as follows: 0.8m for initial blowing, 1.4m~1.6m for intermediate blowing, and 1.0m for carbon extraction; oxygen supply flow rate is 43500Nm³ / h.

7. The converter lean collaborative fast-paced smelting and low iron consumption production control method according to claim 1, characterized in that, The time for the worker to be in position is 2 minutes before the end of the blowing process, and the waiting time for the process is reduced by 2 to 3 minutes.

8. The converter lean collaborative fast-paced smelting and low iron consumption production control method according to claim 1, characterized in that, The refining temperature is 1565.5℃, and the component qualification rate is not less than 85%; the continuous casting speed is not less than 1.35m / min.

9. The converter lean collaborative fast-paced smelting and low iron consumption production control method according to claim 1, characterized in that, Iron consumption is controlled at 850 kg / t to 860 kg / t, and total iron content is stabilized at 1061 kg / t to 1067 kg / t.

10. The converter lean collaborative fast-paced smelting and low iron consumption production control method according to claim 1, characterized in that, The smelting cycle shall not exceed 29.5 minutes, and the iron consumption per unit shall not exceed 855 kg / t.