A top-blown furnace lance tube falling-off efficient disposal method

Abstract

The application discloses a kind of top-blown converter lance tube drop efficient disposal method, including steps: fault determination, hearth insulation and new gun replacement, molten pool temperature rise and preliminary melting, and residual gun elimination and slag reduction.The application is by standby diesel burner and lump coal double heat source superposition heating to quickly raise furnace temperature, using lance wind forced agitation high-temperature melt to flush and melt erosion dropped lance tube, after residual gun completely melts, increase lump coal input to reduce slag, reduce the content of iron tetroxide in slag to within normal production control range.The application can quickly eliminate the process accident caused by lance tube drop into furnace, greatly shorten the idle time of metallurgical furnace, avoid the foam slag spouting accident caused by uneven melt stirring, improve the process safety and production efficiency of smelting system, and no need to add large equipment, with strong universality, can be widely applied to the same type of top-blown smelting furnace.

Description

Technical Field

[0001] This invention relates to the field of non-ferrous metal smelting technology, specifically to an efficient method for handling the detachment of the nozzle of a top-blown furnace lance. Background Technology

[0002] Top-blown furnace smelting is a dynamic immersion smelting process that can integrate oxidation, reduction, and volatilization smelting processes. It has advantages such as simple furnace structure, flexible operation, excellent environmental performance, large material throughput, strong adaptability, high impurity tolerance, and low energy consumption, and is widely used in non-ferrous metal smelting production.

[0003] When processing materials with complex composition and large fluctuations in impurities in a top-blown furnace, the nozzle is highly susceptible to breakage and detachment due to factors such as auxiliary equipment malfunctions, metal fatigue from prolonged use of the nozzle, improper production operations, and substandard welding quality. This malfunction disrupts the normal smelting process within the furnace, and if not addressed promptly, can easily trigger a serious foaming slag accident, not only interfering with normal production but also causing significant economic losses and even safety incidents.

[0004] In conventional production, minor burns or partial breakage of the top-blown spray gun generally do not affect continuous production. However, if the entire spray gun tube detaches, it will cause a sharp drop in the spray gun's air supply efficiency, a continuous deterioration of the furnace condition, and consequently, material accumulation in the furnace, leading to furnace shutdown. Currently, there is limited research in the industry on rapid handling technologies for the complete detachment of the spray gun tube. Due to limitations in existing processes, the efficiency of troubleshooting is low, significantly reducing the operating rate and load rate of the top-blown furnace system.

[0005] Therefore, providing an efficient method for dealing with the detachment of the nozzle of a top-blown furnace spray gun is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the present invention provides an efficient method for handling the detachment of the nozzle of a top-blown furnace lance, so as to quickly melt away the detached lance, resolve the furnace dead fault, and effectively improve the smelting production efficiency.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A highly efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun includes the following steps: 1) Preliminary fault diagnosis: After the nozzle of the spray gun falls off in the top blower furnace, stop all production material supply, raise the damaged spray gun to the first predetermined height, and determine the length, direction of fall and tilt angle of the detached nozzle. 2) Furnace insulation and replacement of new gun: Open the top burner port of the top blown furnace, lower the spare burner into the second predetermined height of the top blown furnace for insulation, and maintain the furnace in a slightly positive pressure state. Then, pull out the old spray gun with the remnant and replace it with a new spray gun. 3) Molten pool heating and initial erosion: Measure the molten pool level, lower the new spray gun to the first distance between its nozzle and the molten pool surface, and add lump coal into the top-blown furnace so that the spare burner and the lump coal burn synchronously to raise the molten pool temperature to the first preset temperature; after the temperature reaches the target, insert the new spray gun into the molten pool at the second distance, and use the spray gun air to stir the molten body to flush and erode the detached gun tube until the detached gun tube is completely submerged in the molten pool; 4) Residual lance removal and slag reduction: Lower the new lance again to the third distance below the molten pool surface. After raising the slag temperature to the second preset temperature, stop the standby burner from burning and heating, and stop supplying oxygen. Continue to melt the detached lance residue by raising and lowering the new lance and using the lance air to stir the high-temperature slag until all the detached lance residue in the slag is melted. After the detached lance is completely melted, increase the amount of lump coal to reduce the slag. Use a slag probe to observe the slag shape and take slag samples for analysis based on the reduction situation. Once the iron tetroxide content in the slag returns to the normal production control range, the fault handling is completed.

[0009] Furthermore, in step 1), the first predetermined height to which the damaged spray gun is raised is 3000-5000mm.

[0010] Furthermore, in step 2), the backup burner is a backup diesel burner, with its fuel consumption controlled at 400 kg / h-700 kg / h, and the furnace pressure controlled at -2 Pa to +5 Pa; the diesel fuel is No. 0 diesel fuel, with a diesel fuel coefficient of 10m. 3 / kg-15Nm 3 / kg; the second predetermined height for the spare burner to enter the furnace is 6000mm.

[0011] Furthermore, in step 3), the lump coal is anthracite with a fixed carbon content ≥68%, the lump coal particle size is 5mm-15mm, the lump coal input rate is controlled at 2-5t / h, and the lump coal fuel coefficient is 6600Nm. 3 -7500Nm 3 / t, coal excess coefficient is 80%-120%; first distance is 200 mm-300 mm, first preset temperature is above 1230℃, second distance is 200 mm-300 mm; oxygen enrichment rate of top-blown spray gun is 28%-35%.

[0012] Furthermore, in step 4), when eliminating residual lances in the molten pool, the lump coal feeding rate is controlled at 1t / h-3t / h, the CO content in the flue gas is controlled at ≤1000ppm, the furnace pressure is maintained at -2Pa to +5Pa, and the lance airflow is controlled at 13000Nm. 3 / h-17000Nm 3 / h, and check the melting status of the residual lance inside the furnace from the furnace opening every 20-30 minutes.

[0013] Furthermore, in step 4), when eliminating residual lance in the molten pool, the third distance is 200-300mm, and the second preset temperature is above 1260℃; and, taking the rising flue temperature and the molten pool temperature as references, the furnace temperature change is judged by monitoring the rising flue temperature to rise by 20℃-80℃ from the original level and the molten pool temperature to rise by 10℃-40℃ from the original level; the lifting range of the new lance is 100 mm-600 mm.

[0014] Furthermore, in step 4), during slag reduction, the lump coal input rate is controlled at 2t / h-8t / h, and the lump coal fuel coefficient is 1000Nm. 3 / t-3000Nm 3 / t, coal surplus coefficient is 60%-120%, and spray gun airflow is controlled at 9000Nm 3 / h-12000Nm 3 / h, control the furnace pressure to -2Pa to -5Pa; Furthermore, in step 4), during slag reduction, the sampling frequency of the molten pool is 5-10 min / time, and the ratio of Fe to SiO2 in the slag is controlled to be 1.1-1.8, and the ratio of CaO to SiO2 is controlled to be 0.15-0.35; the normal production control range of Fe3O4 content in the slag is ≤30%.

[0015] Therefore, the present invention provides an efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun. Compared with the prior art, the present invention has the following beneficial effects: 1) This invention uses a combination of backup diesel burners and oxygen-enriched lump coal as heat sources to rapidly increase the temperature of the furnace, molten pool and slag. It eliminates the need for prolonged furnace heating and relies on high-flow-rate spray gun air to forcefully agitate the molten material and flush away residual gun barrels, significantly reducing the time required to melt and remove detached gun barrels and greatly improving the effective operating time and production capacity of the top-blown furnace.

[0016] 2) This invention incorporates a segmented strong reduction process after the residual lance is completely melted. By quantitatively adding reducing lump coal, the Fe3O4 content in the slag is stably controlled within the safe range of ≤30%, blocking the path of Fe3O4 interacting with copper matte to produce foamy slag, thus eliminating major safety risks to the furnace from the source of the process.

[0017] 3) This invention can quickly melt away metal residue in the furnace, eliminate dead zones in the flow of the melt, reduce mechanical erosion and high-temperature corrosion of the furnace lining, effectively extend the service life of the furnace lining, and reduce the frequency of furnace maintenance and the cost of replacing refractory materials.

[0018] 4) The process parameters of this invention are adjustable and can be adapted to handle the failure of detached spray guns of different lengths and specifications. After minor parameter optimization, it can be extended to various types of top-blown non-ferrous smelting furnaces and kilns of the same type of molten pool. It has strong versatility and significant economic benefits. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] Figure 1 The attached figure is a structural schematic diagram of an efficient treatment system for the detachment of the nozzle of a top-blown furnace spray gun provided by the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0022] This invention is based on Figure 1 Taking the above-described top-blown furnace lance tube detachment high-efficiency handling system as an example, with a Φ5×16m crude copper smelting top-blown furnace as the application object, the system includes a top-blown furnace 1, a rising flue temperature monitoring device 2, a lance 3, a spare burner 4, a molten pool height detection and sampling device 5, a fine-grained copper matte storage bin 6, a lump coal bin 7, a furnace top feeder 8, a lance tube 9, a rising flue 10, a lance holder 11, and a molten pool temperature monitoring device 12. The top of the top-blown furnace 1 has a discharge port 101. The rising flue temperature monitoring device 2 is installed on the side wall of the rising flue 10. The furnace top feeder 8 is located at the top of the top-blown furnace 1 and corresponds to the position of the discharge port 101. The fine-grained copper matte storage bin 6 and the lump coal bin 7 are both located above the furnace top feeder 8. The molten pool temperature monitoring device 12 is installed inside the top-blown furnace 1.

[0023] Example 1: This invention discloses an efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun, comprising the following steps: 1) Preliminary fault diagnosis: After the nozzle 9 of the spray gun 3 falls off in the top blown furnace, all production material supply is stopped, that is, the furnace top feeder 8 is cut off, and the damaged spray gun 3 is raised to the first predetermined height to determine the length, falling direction and tilt angle of the detached nozzle 9; wherein, the first predetermined height of the damaged spray gun 3 is 3000-5000mm. In this embodiment, the damaged spray gun 3 is raised to a height of 4000mm, and it is visually confirmed that the 8000mm detached gun barrel 9 lies flat in the middle of the molten pool with a gentle tilt angle. 2) Furnace insulation and replacement of the new nozzle: Open the top burner port of the top-blown furnace 1, lower the spare burner 4 into the furnace of the top-blown furnace 1 to the second predetermined height for insulation, and maintain the furnace in a slightly positive pressure state. Then, use the nozzle holder 11 to pull out the old nozzle 3 with the remaining section and replace it with a new nozzle. The spare burner 4 is a spare diesel burner, with its fuel consumption controlled at 400kg / h-700kg / h, and the furnace pressure controlled at -2Pa to +5Pa. The diesel fuel is No. 0 diesel, and the diesel fuel coefficient is 10m. 3 / kg-15Nm 3 / kg; The second predetermined height for the spare burner to enter the furnace is 6000mm; In this embodiment, diesel consumption is controlled at 500 kg / h, and the diesel fuel coefficient is 11 m. 3 / kg, with the furnace pressure maintained at +1Pa slightly positive throughout the process; 3) Molten Pool Heating and Initial Erosion: The molten pool level is measured using a molten pool height detection and sampling device 5. The new spray gun is lowered to the first distance between its nozzle and the molten pool surface. Lump coal is added to the top-blown furnace 1, allowing the spare burner 4 to burn synchronously with the lump coal to raise the molten pool temperature to the first preset temperature. Once the temperature reaches the target, the new spray gun is inserted into the molten pool at the second distance. The spray gun air agitates the molten material, scouring and eroding the detached gun tube 9. This process is repeated for 20-30 minutes until the detached gun tube 9 is completely submerged in the molten pool. The lump coal is anthracite with a fixed carbon content ≥68%, a particle size of 5mm-15mm, a lump coal feeding rate controlled at 2-5t / h, and a lump coal fuel coefficient of 6600Nm. 3 -7500Nm 3 / t, coal excess coefficient is 80%-120%; first distance is 200 mm-300 mm, first preset temperature is above 1230℃, second distance is 200 mm-300 mm; oxygen enrichment rate of top-blown spray gun is 28%-35%; In this embodiment, the first distance is 220mm, and anthracite lump coal with a fixed carbon content of 70% and a particle size of 5-15mm is selected. The feeding rate is 3t / h, the oxygen enrichment rate is stable at 30%, and the lump coal fuel coefficient is 6800Nm. 3 / t, coal excess coefficient 90%; first preset temperature 1240℃; second distance 250mm; spray gun airflow 13500Nm³ / h; continuous operation time 25min; 4) Residual lance removal and slag reduction: Lower the new lance again to the third distance below the molten pool surface. After raising the slag temperature to the second preset temperature, stop the standby burner 4 from burning and heating, and stop supplying oxygen. Continue to melt the detached lance residue by raising and lowering the new lance and using the lance air to stir the high-temperature slag until all the detached lance 9 remaining in the slag is melted. After the detached lance 9 is completely melted, increase the amount of lump coal to reduce the slag. Use a slag probe to observe the slag shape and take slag samples for analysis based on the reduction situation. Once the iron tetroxide content in the slag returns to the normal production control range, the fault handling is completed. Specifically, when eliminating residual lances in the molten pool, the lump coal feeding rate is controlled at 1t / h-3t / h, the CO content in the flue gas is controlled at ≤1000ppm, the furnace pressure is maintained at -2Pa to +5Pa, and the lance airflow is controlled at 13000Nm. 3 / h-17000Nm 3 The furnace temperature is monitored at 100-200°C / h, and the melting status of the residual lance inside the furnace is checked from the furnace opening every 20-30 minutes. When eliminating residual lances in the molten pool, the third distance is 200-300mm, and the second preset temperature is above 1260°C. Furthermore, the rising flue temperature and the molten pool temperature are used as references. The furnace temperature is judged by monitoring the rising flue temperature to rise by 20°C-80°C and the molten pool temperature to rise by 10°C-40°C. The lifting range of the new lance is 100 mm-600 mm. During slag reduction, the lump coal feeding rate is controlled at 2t / h-8t / h, and the lump coal fuel coefficient is 1000Nm. 3 / t-3000Nm 3 / t, coal surplus coefficient is 60%-120%, and spray gun airflow is controlled at 9000Nm 3 / h-12000Nm 3 The furnace pressure is controlled at -2Pa to -5Pa per hour. During slag reduction, the molten pool is sampled every 5-10 minutes, and the ratio of Fe to SiO2 in the slag is controlled at 1.1-1.8, and the ratio of CaO to SiO2 is controlled at 0.15-0.35. The Fe3O4 content in the slag is normally controlled within the range of ≤30% during production. In this embodiment, during the stage of eliminating residual lances in the molten pool, the third distance is 250mm, the second preset temperature is 1265℃, the lump coal feeding rate is controlled at 2.5t / h, the real-time CO monitoring of the flue gas is 30ppm, the furnace pressure is maintained at 1Pa, the reciprocating range of the spray gun is 300mm, the spray gun airflow is 14000Nm³ / h, and the melting status of the residual lance is checked through the furnace opening every 20 minutes. During the stage of eliminating residual lances in the molten pool, the rising flue temperature is 30℃ higher than the production baseline, the molten pool temperature is 25℃ higher than the baseline, and the temperature rise rate is stable and controllable. During the slag reduction stage, the lump coal feeding rate is increased to 4t / h, the spray gun airflow is decreased to 11000Nm³ / h, and the furnace negative pressure is controlled at -3Pa. The sampling frequency of molten pool detection is 8min / time. Slag type control: Fe / SiO2=1.3, CaO / SiO2=0.22; after multiple slag sampling and testing, the final Fe3O4 detection value was 21.5%, which is lower than the control limit of ≤30%. The fault handling was completed, and the top blown furnace was switched to normal smelting production system.

[0024] Example 2: This invention discloses an efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun, comprising the following steps: 1) Preliminary fault diagnosis: After the nozzle 9 of the spray gun 3 falls off in the top blown furnace, all production material supply is stopped, that is, the furnace top feeder 8 is cut off, and the damaged spray gun 3 is raised to the first predetermined height to determine the length, falling direction and tilt angle of the detached nozzle 9; wherein, the first predetermined height of the damaged spray gun 3 is 3000-5000mm. In this embodiment, the damaged spray gun 3 is raised to a height of 4500mm, and it is visually confirmed that the 10000mm detached gun barrel 9 is leaning against the furnace wall with the slag surface partially exposed. 2) Furnace insulation and replacement of the new nozzle: Open the top burner port of the top-blown furnace 1, lower the spare burner 4 into the furnace of the top-blown furnace 1 to the second predetermined height for insulation, and maintain the furnace in a slightly positive pressure state. Then, use the nozzle holder 11 to pull out the old nozzle 3 with the remaining section and replace it with a new nozzle. The spare burner 4 is a spare diesel burner, with its fuel consumption controlled at 400kg / h-700kg / h, and the furnace pressure controlled at -2Pa to +5Pa. The diesel fuel is No. 0 diesel, and the diesel fuel coefficient is 10m. 3 / kg-15Nm 3 / kg; The second predetermined height for the spare burner to enter the furnace is 6000mm; In this embodiment, diesel consumption is controlled at 600 kg / h, and the diesel fuel coefficient is 12 m. 3 / kg, with the furnace pressure maintained at a slight positive pressure of +2Pa throughout the entire process; 3) Molten Pool Heating and Initial Erosion: The molten pool level is measured using a molten pool height detection and sampling device 5. The new spray gun is lowered to the first distance between its nozzle and the molten pool surface. Lump coal is added to the top-blown furnace 1, allowing the spare burner 4 to burn synchronously with the lump coal to raise the molten pool temperature to the first preset temperature. Once the temperature reaches the target, the new spray gun is inserted into the molten pool at the second distance. The spray gun air agitates the molten material, scouring and eroding the detached gun tube 9. This process is repeated for 20-30 minutes until the detached gun tube 9 is completely submerged in the molten pool. The lump coal is anthracite with a fixed carbon content ≥68%, a particle size of 5mm-15mm, a lump coal feeding rate controlled at 2-5t / h, and a lump coal fuel coefficient of 6600Nm. 3 -7500Nm 3 / t, coal excess coefficient is 80%-120%; first distance is 200 mm-300 mm, first preset temperature is above 1230℃, second distance is 200 mm-300 mm; oxygen enrichment rate of top-blown spray gun is 28%-35%; In this embodiment, the first distance is 260mm, anthracite lump coal with 70% fixed carbon and a particle size of 5-15mm is selected, the feeding rate is 4.5t / h, the oxygen enrichment rate is stable at 36%, and the lump coal fuel coefficient is 7000Nm. 3 / t, coal excess coefficient 100%; first preset temperature 1250℃; second distance 250mm; spray gun airflow 15000Nm³ / h; continuous operation time 25min; 4) Residual lance removal and slag reduction: Lower the new lance again to the third distance below the molten pool surface. After raising the slag temperature to the second preset temperature, stop the standby burner 4 from burning and heating, and stop supplying oxygen. Continue to melt the detached lance residue by raising and lowering the new lance and using the lance air to stir the high-temperature slag until all the detached lance 9 remaining in the slag is melted. After the detached lance 9 is completely melted, increase the amount of lump coal to reduce the slag. Use a slag probe to observe the slag shape and take slag samples for analysis based on the reduction situation. Once the iron tetroxide content in the slag returns to the normal production control range, the fault handling is completed. Specifically, when eliminating residual lances in the molten pool, the lump coal feeding rate is controlled at 1t / h-3t / h, the CO content in the flue gas is controlled at ≤1000ppm, the furnace pressure is maintained at -2Pa to +5Pa, and the lance airflow is controlled at 13000Nm. 3 / h-17000Nm 3The furnace temperature is monitored at 100-200°C / h, and the melting status of the residual lance inside the furnace is checked from the furnace opening every 20-30 minutes. When eliminating residual lances in the molten pool, the third distance is 200-300mm, and the second preset temperature is above 1260°C. Furthermore, the rising flue temperature and the molten pool temperature are used as references. The furnace temperature is judged by monitoring the rising flue temperature to rise by 20°C-80°C and the molten pool temperature to rise by 10°C-40°C. The lifting range of the new lance is 100 mm-600 mm. During slag reduction, the lump coal feeding rate is controlled at 2t / h-8t / h, and the lump coal fuel coefficient is 1000Nm. 3 / t-3000Nm 3 / t, coal surplus coefficient is 60%-120%, and spray gun airflow is controlled at 9000Nm 3 / h-12000Nm 3 The furnace pressure is controlled at -2Pa to -5Pa per hour. During slag reduction, the molten pool is sampled every 5-10 minutes, and the ratio of Fe to SiO2 in the slag is controlled at 1.1-1.8, and the ratio of CaO to SiO2 is controlled at 0.15-0.35. The Fe3O4 content in the slag is normally controlled within the range of ≤30% during production. In this embodiment, during the stage of eliminating residual lance in the molten pool, the third distance is 280mm, the second preset temperature is 1265℃, the lump coal feeding rate is controlled at 3t / h, the real-time CO monitoring of the flue gas is 400ppm, the furnace pressure is maintained at +2Pa, the reciprocating range of the spray gun is 400mm, the spray gun airflow is 15000Nm³ / h, and the melting status of the residual lance is checked through the furnace opening every 25 minutes. During the stage of eliminating residual lance in the molten pool, the rising flue temperature is 45℃ higher than the production baseline, the molten pool temperature is 32℃ higher than the baseline, and the temperature rise rate is stable and controllable. During the slag reduction stage, the lump coal feeding rate is increased to 5t / h, the spray gun airflow is decreased to 10000Nm³ / h, and the furnace negative pressure is controlled at -1Pa. The sampling frequency of molten pool detection is 8 minutes / time. Slag type control: Fe / SiO2=1.5, CaO / SiO2=0.25; after multiple slag sampling and testing, the final Fe3O4 detection value was 26.2%, which is lower than the control limit of ≤30%. The fault handling was completed, and the top blown furnace was switched to normal smelting production system.

[0025] Example 3: This invention discloses an efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun, comprising the following steps: 1) Preliminary fault diagnosis: After the nozzle 9 of the spray gun 3 falls off in the top blown furnace, all production material supply is stopped, that is, the furnace top feeder 8 is cut off, and the damaged spray gun 3 is raised to the first predetermined height to determine the length, falling direction and tilt angle of the detached nozzle 9; wherein, the first predetermined height of the damaged spray gun 3 is 3000-5000mm. In this embodiment, the damaged spray gun 3 is raised to a height of 5000mm, and it is visually confirmed that the 12000mm detached gun barrel 9 is lying horizontally in the molten pool with its two ends overlapping the furnace wall. 2) Furnace insulation and replacement of the new nozzle: Open the top burner port of the top-blown furnace 1, lower the spare burner 4 into the furnace of the top-blown furnace 1 to the second predetermined height for insulation, and maintain the furnace in a slightly positive pressure state. Then, use the nozzle holder 11 to pull out the old nozzle 3 with the remaining section and replace it with a new nozzle. The spare burner 4 is a spare diesel burner, with its fuel consumption controlled at 400kg / h-700kg / h, and the furnace pressure controlled at -2Pa to +5Pa. The diesel fuel is No. 0 diesel, and the diesel fuel coefficient is 10m. 3 / kg-15Nm 3 / kg; The second predetermined height for the spare burner to enter the furnace is 6000mm; In this embodiment, diesel consumption is controlled at 700 kg / h, and the diesel fuel coefficient is 12.6 m. 3 / kg, with the furnace pressure maintained at a slight positive pressure of +3Pa throughout the entire process; 3) Molten Pool Heating and Initial Erosion: The molten pool level is measured using a molten pool height detection and sampling device 5. The new spray gun is lowered to the first distance between its nozzle and the molten pool surface. Lump coal is added to the top-blown furnace 1, allowing the spare burner 4 to burn synchronously with the lump coal to raise the molten pool temperature to the first preset temperature. Once the temperature reaches the target, the new spray gun is inserted into the molten pool at the second distance. The spray gun air agitates the molten material, scouring and eroding the detached gun tube 9. This process is repeated for 20-30 minutes until the detached gun tube 9 is completely submerged in the molten pool. The lump coal is anthracite with a fixed carbon content ≥68%, a particle size of 5mm-15mm, a lump coal feeding rate controlled at 2-5t / h, and a lump coal fuel coefficient of 6600Nm. 3 -7500Nm 3 / t, coal excess coefficient is 80%-120%; first distance is 200 mm-300 mm, first preset temperature is above 1230℃, second distance is 200 mm-300 mm; oxygen enrichment rate of top-blown spray gun is 28%-35%; In this embodiment, the first distance is 300mm, anthracite lump coal with 70% fixed carbon and a particle size of 5-15mm is selected, the feeding rate is 5.5t / h, the oxygen enrichment rate is stable at 40%, and the lump coal fuel coefficient is 7500Nm. 3 / t, coal excess coefficient 110%; first preset temperature 1260℃; second distance 300mm; spray gun airflow 16500Nm³ / h; continuous operation time 25min; 4) Residual lance removal and slag reduction: Lower the new lance again to the third distance below the molten pool surface. After raising the slag temperature to the second preset temperature, stop the standby burner 4 from burning and heating, and stop supplying oxygen. Continue to melt the detached lance residue by raising and lowering the new lance and using the lance air to stir the high-temperature slag until all the detached lance 9 remaining in the slag is melted. After the detached lance 9 is completely melted, increase the amount of lump coal to reduce the slag. Use a slag probe to observe the slag shape and take slag samples for analysis based on the reduction situation. Once the iron tetroxide content in the slag returns to the normal production control range, the fault handling is completed. Specifically, when eliminating residual lances in the molten pool, the lump coal feeding rate is controlled at 1t / h-3t / h, the CO content in the flue gas is controlled at ≤1000ppm, the furnace pressure is maintained at -2Pa to +5Pa, and the lance airflow is controlled at 13000Nm. 3 / h-17000Nm 3 The furnace temperature is monitored at 100-200°C / h, and the melting status of the residual lance inside the furnace is checked from the furnace opening every 20-30 minutes. When eliminating residual lances in the molten pool, the third distance is 200-300mm, and the second preset temperature is above 1260°C. Furthermore, the rising flue temperature and the molten pool temperature are used as references. The furnace temperature is judged by monitoring the rising flue temperature to rise by 20°C-80°C and the molten pool temperature to rise by 10°C-40°C. The lifting range of the new lance is 100 mm-600 mm. During slag reduction, the lump coal feeding rate is controlled at 2t / h-8t / h, and the lump coal fuel coefficient is 1000Nm. 3 / t-3000Nm 3 / t, coal surplus coefficient is 60%-120%, and spray gun airflow is controlled at 9000Nm 3 / h-12000Nm 3 The furnace pressure is controlled at -2Pa to -5Pa per hour. During slag reduction, the molten pool is sampled every 5-10 minutes, and the ratio of Fe to SiO2 in the slag is controlled at 1.1-1.8, and the ratio of CaO to SiO2 is controlled at 0.15-0.35. The Fe3O4 content in the slag is normally controlled within the range of ≤30% during production. In this embodiment, during the stage of eliminating residual lances in the molten pool, the third distance is 300mm, the second preset temperature is 1270℃, the lump coal feeding rate is controlled at 3.5t / h, the real-time CO monitoring of the flue gas is 700ppm, the furnace pressure is maintained at +4Pa, the reciprocating range of the spray gun is 500mm, the spray gun airflow is 16000Nm³ / h, and the melting status of the residual lance is checked through the furnace opening every 30 minutes. During the stage of eliminating residual lances in the molten pool, the rising flue temperature is 65℃ higher than the production baseline, the molten pool temperature is 38℃ higher than the baseline, and the temperature rise rate is stable and controllable. During the slag reduction stage, the lump coal feeding rate is increased to 6t / h, the spray gun airflow is decreased to 9800Nm³ / h, and the furnace negative pressure is controlled at -5Pa. The sampling frequency of molten pool detection is 10min / time. Slag type control: Fe / SiO2=1.65, CaO / SiO2=0.3; after multiple slag sampling and testing, the final Fe3O4 detection value was 28.8%, which is lower than the control limit of ≤30%. The fault handling was completed, and the top blown furnace was switched to normal smelting production system.

[0026] Verification examples confirm that the method of this invention is effective for use with top-blown furnace melting lances, effectively reducing the risk of furnace blockage, foamy slag, and refractory brick spalling and collapse caused by lance breakage or detachment. It improves the production capacity of top-blown furnaces and significantly reduces production costs and safety and environmental risks. The control parameters and operating procedures involved in this method can be widely applied to similar or related smelting furnaces after slight optimization.

[0027] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0028] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for efficiently handling the detachment of the nozzle of a top-blown furnace spray gun, characterized in that, Includes the following steps: 1) Preliminary fault diagnosis: After the nozzle of the spray gun falls off in the top blower furnace, stop all production material supply, raise the damaged spray gun to the first predetermined height, and determine the length, direction of fall and tilt angle of the detached nozzle. 2) Furnace insulation and replacement of new gun: Open the top burner port of the top blown furnace, lower the spare burner into the second predetermined height of the top blown furnace for insulation, and maintain the furnace in a slightly positive pressure state. Then, pull out the old spray gun with the remnant and replace it with a new spray gun. 3) Molten pool heating and initial erosion: Measure the molten pool level, lower the new spray gun to the first distance between its nozzle and the molten pool surface, and add lump coal into the top-blown furnace so that the spare burner and the lump coal burn synchronously to raise the molten pool temperature to the first preset temperature; after the temperature reaches the target, insert the new spray gun into the molten pool at the second distance, and use the spray gun air to stir the molten body to flush and erode the detached gun tube until the detached gun tube is completely submerged in the molten pool; 4) Residual lance removal and slag reduction: Lower the new lance again to the third distance below the molten pool surface. After raising the slag temperature to the second preset temperature, stop the standby burner from burning and heating, and stop supplying oxygen. Continue to melt the detached lance residue by raising and lowering the new lance and using the lance air to stir the high-temperature slag until all the detached lance residue in the slag is melted. After the detached lance is completely melted, increase the amount of lump coal to reduce the slag. Use a slag probe to observe the slag shape and take slag samples for analysis based on the reduction situation. Once the iron tetroxide content in the slag returns to the normal production control range, the fault handling is completed.

2. The efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun according to claim 1, characterized in that, In step 1), the first predetermined height for raising the damaged spray gun is 3000-5000mm.

3. The efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun according to claim 1, characterized in that, In step 2), the backup burner is a backup diesel burner, with its fuel consumption controlled at 400 kg / h-700 kg / h, and the furnace pressure controlled at -2 Pa to +5 Pa; the diesel fuel is No. 0 diesel fuel, and the diesel fuel coefficient is 10m. 3 / kg-15Nm 3 / kg; the second predetermined height for the spare burner to enter the furnace is 6000mm.

4. The efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun according to claim 1, characterized in that, In step 3), the lump coal is anthracite with a fixed carbon content ≥68%, the lump coal particle size is 5mm-15mm, the lump coal input rate is controlled at 2-5t / h, and the lump coal fuel coefficient is 6600Nm. 3 -7500Nm 3 / t, coal excess coefficient is 80%-120%; first distance is 200 mm-300 mm, first preset temperature is above 1230℃, second distance is 200 mm-300 mm; oxygen enrichment rate of top-blown spray gun is 28%-35%.

5. The efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun according to claim 1, characterized in that, In step 4), when eliminating residual lances in the molten pool, the lump coal feeding rate is controlled at 1t / h-3t / h, the CO content in the flue gas is controlled at ≤1000ppm, the furnace pressure is maintained at -2Pa to +5Pa, and the lance airflow is controlled at 13000Nm. 3 / h-17000Nm 3 / h, and check the melting status of the residual lance inside the furnace from the furnace opening every 20-30 minutes.

6. The efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun according to claim 5, characterized in that, In step 4), when eliminating residual lance in the molten pool, the third distance is 200-300mm, and the second preset temperature is above 1260℃. Furthermore, using the rising flue temperature and the molten pool temperature as references, the furnace temperature change is judged by monitoring the rising flue temperature to rise by 20℃-80℃ and the molten pool temperature to rise by 10℃-40℃. The lifting range of the new lance is 100 mm-600 mm.

7. The efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun according to claim 6, characterized in that, In step 4), during slag reduction, the lump coal input rate is controlled between 2t / h and 8t / h, and the lump coal fuel coefficient is 1000 Nm. 3 / t-3000Nm 3 / t, coal surplus coefficient is 60%-120%, and spray gun airflow is controlled at 9000Nm 3 / h-12000Nm 3 / h, control the furnace pressure to -2Pa to -5Pa.

8. The efficient method for handling the detachment of the nozzle of a top-blown furnace spray gun according to claim 7, characterized in that, In step 4), during slag reduction, the sampling frequency of the molten pool is 5-10 min / time, and the ratio of Fe to SiO2 in the slag is controlled to be 1.1-1.8, and the ratio of CaO to SiO2 is controlled to be 0.15-0.35; the normal production control range of Fe3O4 content in the slag is ≤30%.

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