Oxygen-enriched side-blown bath smelting furnace and oxygen lance arrangement control method

Abstract

The invention discloses an oxygen-enriched side-blown bath smelting furnace and an oxygen lance arrangement control method, and relates to the technical field of metallurgical smelting equipment, the oxygen-enriched side-blown bath smelting furnace comprises a hearth, a furnace body and a furnace top, the hearth is of a double-layer structure composed of an outer steel plate and lining refractory bricks, the furnace top is provided with a feeding port and a flue port, and three layers of copper water jackets are welded to the outer wall of the furnace body from top to bottom; a first oxygen discharging gun set, a second oxygen discharging gun set and a third oxygen discharging gun set are arranged on the two sides of the furnace body, the first oxygen discharging gun set and the second oxygen discharging gun set are located at the stirring position of the molten pool and close to the hearth, and the two sides of the third oxygen discharging gun set are arranged in a staggered mode. A nozzle of the third oxygen lance group faces the liquid level of the molten pool; the overall gas-solid-liquid interphase mass and heat transfer process is strengthened, the copper matte fuel consumption is reduced by 18%-22%, the copper matte recovery rate is increased by 3%-8%, meanwhile, furnace lining corrosion is reduced by homogenizing molten pool temperature distribution, and the service life of equipment is prolonged; and the system is suitable for reinforced smelting of refractory materials such as complex-component metal ores and electronic wastes, and has remarkable energy-saving and emission-reducing benefits.

Description

Technical Field

[0001] The present invention relates to the technical field of metallurgical smelting equipment, and in particular to an oxygen-enriched side-blowing molten pool smelting furnace and an oxygen lance arrangement control method. Background Art

[0002] Oxygen-enriched side-blown bath smelting furnaces are widely used in the smelting of non-ferrous metals such as copper, lead, and zinc. Traditional oxygen lance systems utilize a single row of oxygen lances with fixed positions and a direct jet angle. This can lead to uneven oxygen distribution, poor bath fluidity, localized overheating, and severe disturbance of the matte layer. This results in difficult copper slag separation, low smelting efficiency, and increased energy consumption. A search of Chinese patent number CN118936087A discloses a multi-row staggered oxygen lance layout that increases the reaction rate by expanding the oxygen jet coverage area. However, the design adopts a fixed inclined injection (0-60 degrees), which causes excessive enrichment of oxygen in the upper layer of the molten pool, causing local overoxidation, and does not take into account the consumption of the furnace lining by the violent reaction inside the molten pool; Chinese patent number CN118274613A discloses a side-blown furnace structure, which improves the sedimentation separation effect by setting a slag baffle in the furnace, but the design only adopts one air injection, resulting in low oxygen utilization rate inside the molten pool and fast bubble escape speed, thereby increasing fuel consumption; Chinese patent number CN117535518A discloses an oxygen-enriched side-blown furnace air supply structure, which enables the oxygen in the furnace to fully react and reduces the dust content of the flue gas through multi-level gradient supply, but the structure lacks real-time monitoring of the molten pool temperature field and the molten pool liquid level fluctuation, and cannot suppress thermal imbalance caused by fluctuations in material composition.

[0003] In summary, in the existing technology, the coefficient of variation of the oxygen concentration in the melt is very high under the traditional arrangement, and local overoxidation and insufficient reduction coexist, resulting in fluctuations in the matte recovery rate and increased copper content in the slag; at the same time, the common oxygen lance design with a fixed inclination angle and insertion depth is difficult to adapt to fluctuations in the raw material composition. When the processing volume changes beyond a specific value, the melt liquid level fluctuates violently, which not only accelerates the erosion of refractory materials, but also leads to an increase in the smoke rate. Summary of the Invention

[0004] The purpose of the present invention is to solve the above problems and provide an oxygen-enriched side-blowing molten pool smelting furnace and an oxygen lance arrangement control method.

[0005] To achieve the above-mentioned purpose, the technical solution of the present invention is: an oxygen-enriched side-blown molten pool smelting furnace, comprising a furnace hearth, a furnace body and a furnace top, the furnace hearth being a double-layer structure composed of an outer steel plate and an inner lining of refractory bricks, the furnace top being provided with a charging port and a flue port, and a three-layer copper water jacket being welded from top to bottom on the outer wall of the furnace body, a first row of oxygen lance groups, a second row of oxygen lance groups and a third row of oxygen lance groups being provided on both sides of the furnace body, the first row of oxygen lance groups and the second row of oxygen lance groups being located at the molten pool stirring area and close to the furnace hearth, and the third row of oxygen lance groups being arranged in an staggered manner on both sides; and the nozzles of the third row of oxygen lance groups are facing the liquid surface of the molten pool.

[0006] Preferably, the first row of oxygen lance groups is arranged in the slag layer area, the diameter of the first row of oxygen lance groups is 38mm-48mm, the first row of oxygen lance groups is distributed with a phase difference, the distribution interval is 200-300mm, the first row of oxygen lance groups is tilted to the right, and the inclination angle is 5-15°, the second row of oxygen lance groups is located 200mm-1750mm vertically above the first row of oxygen lance groups, the diameter of the second row of oxygen lance groups is 38mm-48mm, the third row of oxygen lance groups is tilted downward, and the inclination angle is 20-60°, the diameter of the third row of spray guns is 32mm-38mm, and the third row of oxygen lance groups is located 200mm-2750mm vertically above the second row of oxygen lance groups.

[0007] Preferably, temperature sensors are provided at the flue opening and the upper, middle and lower parts of the molten pool respectively.

[0008] Preferably, the surface of the smelting area of the first oxygen lance group is covered with SIC-SI3N4 composite ceramics with a thickness of 50 mm, the middle layer is covered with chrome corundum bricks, and the bottom layer is covered with magnesia-alumina spinel bricks.

[0009] Preferably, a stepping motor is installed below the gas valve of the third row oxygen lance group.

[0010] A method for controlling the arrangement of oxygen lances in an oxygen-enriched side-blown molten pool smelting furnace comprises the following steps: S1: Three rows of heterogeneous oxygen lances are installed on both sides of the furnace body. The first row of main oxygen lances is close to the slag layer area of the furnace hearth and tilted 5-15 degrees to the right to provide strong turbulent stirring at the bottom. The second row of main oxygen lances is arranged vertically 200-1750mm above the first row to achieve diffuse oxygen supply in the middle and upper layers. The third row of auxiliary oxygen lances is located above the second row, tilted 20-60 degrees downward and staggered to form a vortex flow field to extend the oxygen residence time. S2: A gradient refractory layer is attached to the slag layer area, and a temperature sensor is installed. A three-layer copper water jacket cooling system is also configured to control the cooling water flow in a gradient from top to bottom. S3: An intelligent dynamic control system uses a stepper motor to adjust the inclination and insertion depth of the third row oxygen lance in real time. The PID algorithm and fluid dynamics model are combined to dynamically optimize oxygen distribution and injection parameters based on temperature and liquid level fluctuation data. S4: Verify energy-saving effects through industrial trials, calibrate oxygen lance parameters and refractory layer configuration, ensure uniformity of molten pool reaction, increase oxygen utilization to 88%-92%, and extend equipment life.

[0011] Preferably, in step S1, the first and second rows of oxygen lance groups are arranged in the core area of molten pool stirring, and adopt differentiated diameters and injection angles to achieve the coordination of strong turbulent stirring at the bottom and diffuse oxygen supply in the middle and upper layers; the third row of oxygen lance group forms a vortex flow field through inclined injection to extend the oxygen residence time.

[0012] Preferably, the intelligent dynamic control system in S3 controls the first row of main oxygen lance groups, the second row of main oxygen lance groups and the third row of auxiliary oxygen lance groups; the temperature sensors are arranged at the flue port and the upper, middle and lower parts of the molten pool to monitor the temperature distribution in real time; the stepper motor is located below the gas valve of the third row of oxygen lance groups (8) and adjusts the oxygen lance angle and insertion depth according to the PID algorithm; the central controller optimizes the oxygen flow distribution and injection angle based on the temperature data and generates dynamic control instructions.

[0013] Preferably, an integrated adaptive optimization parameter module and a real-time effect evaluation module are provided in the intelligent dynamic control system.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The synergistic effect of the three rows of oxygen lances improves the uniformity of oxygen distribution in the molten pool, stabilizes the matte recovery rate at over 98.5%, and reduces the copper content in the slag to below 0.8%; 2. The vortex effect created by staggered injection increases oxygen utilization to 88%-92%, reducing matte fuel consumption by 18%-22%; 3. A gradient refractory layer was formed in the melting area. The surface layer was covered with SIC-SI3N4 composite ceramic (50 mm thick, thermal conductivity 18 W / m·K), the middle layer was covered with chrome corundum bricks (Al2O3 ≥ 90%, Cr2O3 8%, 100 mm thick), and the bottom layer was covered with magnesia-alumina spinel bricks (150 mm thick). The measured erosion rate was reduced from 3.2 mm / day to 0.7 mm / day. 4. The intelligent dynamic control system solves the efficiency and stability problems caused by control lag, parameter isolation, and reliance on manual experience in traditional smelting processes through the triple coupling of real-time, collaborative, and adaptable features. This reduces energy consumption by 18%-22% for matte fuel, improves quality by stabilizing the matte recovery rate at over 98.5%, improves production continuity by reducing unplanned downtime by 80%, and enables intelligent process transformation from "experience-driven" to "data-driven," providing core support for the digital transformation of the metallurgical industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the cross-sectional structure of the front of the oxygen-enriched side-blowing molten pool smelting furnace. Figure 2 Schematic diagram of the cross-sectional structure of the oxygen-enriched side-blowing molten pool smelting furnace Figure 3This is a plan view of the oxygen injection device of the first row of oxygen lances in the oxygen-enriched side-blown molten pool smelting furnace.

[0016] Figure 4 This is a simplified diagram of the intelligent dynamic control system.

[0017] In the figure: 1. furnace hearth, 2. furnace body, 3. flue port, 4. observation port, 5. charging port, 6. first row of oxygen lance groups, 7. second row of oxygen lance groups, 8. third row of oxygen lance groups, 9. copper water jacket, 10. slag outlet, 11. slag sticking port, 12. refractory brick lining, 13. steel frame, 14. outer steel plate. DETAILED DESCRIPTION

[0018] The present invention will now be described in further detail with reference to the accompanying drawings, which are simplified schematic diagrams that illustrate the basic structure of the present invention in a schematic manner, and thus only show components related to the present invention.

[0019] Combine Figures 1-4 As shown, the oxygen-enriched side-blown molten pool smelting furnace provided in this embodiment includes a furnace body consisting of a furnace hearth 1, a furnace body 2, and a furnace roof. The furnace hearth 1 has a double-layer structure, with an outer steel plate 14 supported by a steel frame 13 as the outer layer and a lining of refractory bricks 12 as the inner layer. The refractory bricks are 450 mm thick and have an Al2O3 content of ≥85%. A charging port 5 (800 mm in diameter) is provided in the center of the furnace top, and a flue port 3 (1.2×1.5 m in cross section) is provided at the rear end. A temperature sensor (K-type thermocouple, measuring range 0-1600°C) and a high-temperature resistant observation window 4 are embedded in the flue port. The first row of oxygen lances 6, the second row of oxygen lances 7, and the third row of oxygen lances 8 are located on one side of the furnace body 2 and are equipped with 8-10 nozzles. A three-layer copper water jacket 9 (40 mm thick) is welded to the outer wall of the furnace body 2 from top to bottom, with a spacing of 30 mm between adjacent water jackets. The cooling water flow rate is controlled at 12 m³ / h, 15 m³ / h, and 18 m³ / h from top to bottom, forming a gradient cooling. In particular, a gradient refractory layer is formed in the smelting area of the slag layer. The surface layer is covered with SIC-SI3N4 composite ceramics (50 mm thick, thermal conductivity 18 W / m·K), and the middle layer is covered with chrome corundum bricks (Al2O3 ≥ 90%, Cr2O3 8%, thickness 100mm), the outer layer is covered with magnesia-alumina spinel bricks (thickness 150mm), The first row of oxygen lances 6 is arranged 100 mm above the slag layer of the furnace hearth, with an oxygen lance diameter of 48 mm, a horizontal spacing of 650 mm, and an overall inclination of 10 degrees to the right. The oxygen enrichment concentration is 85%, and the flow rate is 2400 Nm³ / h, which is used for strong turbulent stirring at the bottom of the molten pool. The second row of oxygen lances 7 is located 300 mm vertically above the first row, with a diameter of 48 mm, a horizontal spacing of 750 mm, vertical injection, an oxygen enrichment concentration of 70%, and a flow rate of 1600 Nm³ / h to achieve diffuse oxygen supply in the middle and upper layers. The third row of oxygen lances 8 are staggered on both sides (displacement of 400 mm), with an oxygen lance diameter of 32 mm, a downward inclination of 30 degrees, a nozzle 2000 mm from the molten pool liquid surface, a flow rate of 1000 Nm³ / h, and a vortex injection to extend the oxygen residence time. Industrial tests in this embodiment have verified that the smelting intensity inside the molten pool reaches 35t / (m²·d), the measured erosion rate of the internal refractory layer is reduced from 3.2mm / day to 0.7mm / day, and the oxygen utilization rate is increased to 92.5%, which saves more than 18% energy compared to traditional furnace types. Example

[0020] like Figures 1-4 As shown, in the example of lead smelting, existing equipment was modified: for the original oxygen-enriched side-blown molten pool smelting furnace, the original single row of oxygen lances was removed, and oxygen lances were reinstalled on both sides of the furnace body in accordance with the present invention. The first row of oxygen lances was equipped with 16 oxygen lances with a diameter of 42 mm. Adjacent oxygen lances were phase-shifted by 250 mm and sprayed to the right at a 10-degree angle, located in the slag layer area near the furnace hearth. The second row of oxygen lances was equipped with 16 oxygen lances with a diameter of 42 mm, located 350 mm vertically above the first row of oxygen lances. The third row of oxygen lances was equipped with 12 oxygen lances with a diameter of 35 mm, tilted downward by 40 degrees, with their nozzles facing the molten pool liquid surface. They were located 2550 mm vertically above the second row of oxygen lances, and were staggered on both sides. Temperature sensors are installed at the flue port and the upper / middle / lower part of the molten pool (melt / slag interface / molten pool surface area). At the same time, the cooling system is modified. The outer wall of the furnace body 2 is welded with three layers of copper water jacket 9 (thickness 40mm) from top to bottom. The distance between adjacent water jackets is 30mm. The cooling water flow is controlled at 12m³ / h, 15m³ / h, and 18m³ / h from top to bottom to form gradient cooling. A stepper motor is installed below the gas valve of the third row oxygen gun group 8, which is connected to the intelligent dynamic control system built on the industrial computer. The central controller has a built-in molten pool flow controller. The molten pool dynamics model adjusts injection parameters by simulating the oxygen diffusion path in real time. Temperature sensors collect the temperatures of the upper (1200-1250°C), middle (1150-1180°C), and lower (1100-1130°C) parts of the molten pool every 5 seconds. The central controller compares the temperatures to the set temperature curve and calculates the deviation value ΔT. If ΔT is greater than 30°C, the stepper motor is activated to adjust the inclination angle of the third row of oxygen lances by ±5° and increase the flow rate by 10%. If the liquid level fluctuation is greater than 5cm, the stepper motor adjusts the oxygen lance insertion depth at a speed of 0.5mm / s. After the transformation in this embodiment is completed, the oxygen utilization rate is increased from 70% to 85%, the lead recovery rate is increased by 5%, the fuel consumption is reduced by 20%, the furnace lining erosion rate is significantly reduced, and the equipment service life is expected to be extended by 2 years, effectively reducing production costs. Example

[0021] like Figures 1-4 As shown, a large oxygen-enriched side-blown molten pool smelting furnace with a hearth diameter of 3.6 meters and a furnace body height of 10 meters was constructed. The first row of oxygen lances, group 6, was equipped with 32 oxygen lances with a diameter of 48 mm. Adjacent oxygen lances were positioned 300 mm apart in phase, spraying to the right at a 15-degree inclination angle and located in the slag layer area. The second row of oxygen lances, group 7, was equipped with 32 oxygen lances with a diameter of 48 mm and located 550 mm vertically above the first row of oxygen lances, group 6. The third row of oxygen lances, group 8, was equipped with 24 oxygen lances with a diameter of 38 mm and tilted downward at a 60-degree angle, with the nozzles facing the molten pool surface. They were located 2650 mm vertically above the second row of oxygen lances, and were staggered on both sides. High-precision sensors are arranged at the flue mouth and the upper / middle / lower part of the molten pool (melt / copper slag interface / molten pool surface area) to monitor the temperature distribution in real time and build a comprehensive temperature monitoring network. A high-performance stepper motor is installed below the gas valve of the third-row oxygen lance group 8, which is connected to the cloud computing-based central controller (with a built-in fluid dynamics module). The temperature inside the molten pool and the changes in the liquid level are monitored by the arranged high-precision sensors, and the signals are fed back to the central controller. The PID control algorithm is used to adjust the inclination angle and insertion depth of the third-row oxygen lance 8. The intelligent dynamic control system also integrates an adaptive optimization parameter module and a real-time effect evaluation module. Through long-term experience learning and adjustment, the feedback signal becomes more and more accurate.

[0022] After the formal operation of this embodiment, the copper matte fuel consumption was reduced by 18%-22%, the matte recovery rate was stabilized at more than 98.5%, and the unplanned production shutdown was reduced by 80%.

[0023] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. An oxygen-enriched side-blown molten pool smelting furnace, characterized by: The invention comprises a furnace cylinder (1), a furnace body (2) and a furnace top, wherein the furnace cylinder (1) is composed of an outer steel plate (14) and an inner lining refractory brick (12) to form a double-layer structure, the furnace top is provided with a charging port (5) and a flue port (3), the outer wall of the furnace body (2) is welded with three layers of copper water jacket (9) from top to bottom, the first row of oxygen lance groups (6), the second row of oxygen lance groups (7) and the third row of oxygen lance groups (8) are provided on both sides of the furnace body (2), the first row of oxygen lance groups (6) and the second row of oxygen lance groups (7) are located at the molten pool stirring position and close to the furnace cylinder (1), and the third row of oxygen lance groups (8) are arranged in a staggered manner on both sides; and the nozzles of the third row of oxygen lance groups (8) face the liquid surface of the molten pool.

2. The oxygen-enriched side-blown molten pool smelting furnace according to claim 1, characterized in that: The first row of oxygen lance groups (6) are arranged in the slag layer area, the diameter of the first row of oxygen lance groups (6) is 38mm-48mm, the first row of oxygen lance groups (6) are distributed in a phase difference manner, and the distribution interval is 200-300mm, the first row of oxygen lance groups (6) sprays tilted to the right, and the tilt angle is 5-15°, the second row of oxygen lance groups (7) are located 200mm-1750mm vertically above the first row of oxygen lance groups (6), the diameter of the second row of oxygen lance groups (7) is 38mm-48mm, the third row of oxygen lance groups (8) sprays tilted downward, and the tilt angle is 20-60°, the diameter of the third row of lances (8) is 32mm-38mm, and the third row of oxygen lance groups (8) are located 200mm-2750mm vertically above the second row of oxygen lance groups (7).

3. The oxygen-enriched side-blown molten pool smelting furnace according to claim 1, characterized in that: Temperature sensors are respectively set at the upper, middle and lower parts of the flue outlet and the molten pool.

4. The oxygen-enriched side-blown molten pool smelting furnace according to claim 1 or 2, characterized in that: The first row of oxygen lances (6) has SIC-SI3N4 composite ceramics on the surface of the smelting area with a thickness of 50 mm, a middle layer with chrome corundum bricks, and a bottom layer with magnesia-alumina spinel bricks.

5. The oxygen-enriched side-blown molten pool smelting furnace according to claim 1 or 2, characterized in that: A stepping motor is installed below the gas valve of the third row oxygen gun group (8).

6. A method for controlling the arrangement of oxygen lances in an oxygen-enriched side-blowing molten pool smelting furnace, characterized by: The steps include: S1: Three rows of heterogeneous oxygen lances are installed on both sides of the furnace body. The first row of main oxygen lances is close to the slag layer area of the furnace hearth and tilted 5-15 degrees to the right to provide strong turbulent stirring at the bottom. The second row of main oxygen lances is arranged vertically 200-1750mm above the first row to achieve diffuse oxygen supply in the middle and upper layers. The third row of auxiliary oxygen lances is located above the second row, tilted 20-60 degrees downward and staggered to form a vortex flow field to extend the oxygen residence time. S2: A gradient refractory layer is attached to the slag layer area, and a temperature sensor is installed. A three-layer copper water jacket cooling system is also configured to control the cooling water flow in a gradient from top to bottom. S3: An intelligent dynamic control system uses a stepper motor to adjust the inclination and insertion depth of the third row oxygen lance in real time. The PID algorithm and fluid dynamics model are combined to dynamically optimize oxygen distribution and injection parameters based on temperature and liquid level fluctuation data. S4: Verify energy-saving effects through industrial trials, calibrate oxygen lance parameters and refractory layer configuration, ensure uniformity of molten pool reaction, increase oxygen utilization to 88%-92%, and extend equipment life.

7. The method for controlling the arrangement of oxygen lances in an oxygen-enriched side-blown molten pool smelting furnace according to claim 6, characterized in that: In step S1, the first and second rows of oxygen lance groups are arranged in the core stirring area of the molten pool, and adopt differentiated diameters and injection angles to achieve synergy between strong turbulent stirring at the bottom and diffuse oxygen supply in the middle and upper layers; the third row of oxygen lance group forms a vortex flow field through inclined injection to extend the oxygen residence time.

8. The method for controlling the arrangement of oxygen lances in an oxygen-enriched side-blown molten pool smelting furnace according to claim 6, characterized in that: The intelligent dynamic control system in S3 controls the first row of main oxygen lance groups, the second row of main oxygen lance groups and the third row of auxiliary oxygen lance groups; the temperature sensors are arranged at the flue port and the upper, middle and lower parts of the molten pool to monitor the temperature distribution in real time; the stepper motor is located below the gas valve of the third row of oxygen lance groups (8) and adjusts the oxygen lance angle and insertion depth according to the PID algorithm; the central controller optimizes the oxygen flow distribution and injection angle based on temperature data and generates dynamic control instructions.

9. The method for controlling the arrangement of oxygen lances in an oxygen-enriched side-blown molten pool smelting furnace according to claim 8, characterized in that: The intelligent dynamic control system is provided with an integrated adaptive optimization parameter module and a real-time effect evaluation module.

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