Ventilation pressure maintaining operation method for blast furnace upper portion water leakage cooling wall

Abstract

The application discloses a kind of blast furnace upper portion water leakage cooling wall ventilation pressure maintaining operation method and system.Method includes: after detecting blast furnace water leakage, water control and gas overflow monitoring are carried out to water leakage cooling wall, and composition analysis is carried out to collected gas;After confirming that conditions are met, high-pressure clean gas and high-pressure nitrogen are connected to the water inlet end of water leakage cooling wall under the condition that blast furnace is blown out;During the process of blast furnace blowing, according to the change of blast volume, adjust the opening degree of clean gas and nitrogen valve in echelon;Under full blast steady state, calculate and adjust the target flow of single cooling wall by combining airflow distribution model;Real-time monitoring of ventilation temperature and cooling wall inner surface temperature, self-adaptive adjustment of double gas source valve opening, and edge cloth intervention or extreme protection operation is started when overtemperature occurs.The application effectively prevents gas backflow in the furnace through multi-source airflow follow-up control and dynamic heat exchange regulation, prolongs the service life of water leakage cooling wall and ensures the safety of blast furnace production.

Description

Technical Field

[0001] This invention relates to the field of maintenance and operation control technology for blast furnace ironmaking equipment, specifically a method for maintaining pressure by venting air through the water-cooled wall above the blast furnace body. Background Technology

[0002] During blast furnace production, the upper cooling wall of the furnace body is subjected to high temperature thermal shock and furnace material wear for a long time, which can easily cause damage and water leakage. If water continues to flow after the cooling wall leaks, it will cause temperature fluctuations in the furnace and cause production failures. Therefore, the industry usually adopts the operation of controlling water and introducing gas into the leaking cooling wall to maintain pressure and cool.

[0003] In existing cooling wall venting and pressure-maintaining operations, the gas flow rate is usually set as a fixed parameter based on the operator's experience. During the blast furnace's transition from shutdown to restart and during steady-state production, the existing operating method cannot dynamically control the airflow according to the changes in the actual blast furnace air volume. It also lacks a quantitative allocation mechanism that combines the blast furnace airflow distribution model and the air-gas conversion coefficient to accurately calculate the target flow rate. This non-quantitative venting method easily leads to a mismatch between the pressure-maintaining flow rate inside the cooling wall and the actual operating conditions of the blast furnace, resulting not only in wasted gas resources but also in difficulty in effectively preventing the backflow of high-temperature gas inside the furnace.

[0004] Existing pressure-holding cooling methods mostly use a single gas or a statically proportioned gas supply, without fully considering the changes in the cooling capacity of the introduced gas itself. In actual operation, existing technologies lack a dual real-time monitoring mechanism for the temperature of the introduced gas and the temperature of the inner surface of the cooling wall. When the introduced gas exceeds the temperature or its own cooling capacity is insufficient, it is impossible to promptly adjust the heat exchange and supplement the nitrogen cold source based on the temperature feedback. This will cause the leaking cooling wall body to be damaged by secondary thermal stress, thereby shortening its remaining service life. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for ventilating and pressurizing the upper water-leaking cooling wall of a blast furnace, which solves the problem that non-quantitative venting methods can easily lead to a mismatch between the internal pressure-maintaining flow rate of the cooling wall and the actual operating conditions of the blast furnace, resulting in wasted gas resources.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for maintaining pressure by venting through a water-cooled wall in the upper part of a blast furnace, characterized by comprising the following steps: Step 1: After detecting water leakage, control the water flow in the leaking cooling wall and monitor for gas overflow, and collect the overflowing gas for composition analysis; Step 2: After confirming that the carbon monoxide content in the gas meets the set conditions, control the blast furnace to enter the shutdown state, seal the water outlet of the leaking cooling wall, and connect the high-pressure clean gas in the clean gas pipeline and the high-pressure nitrogen in the nitrogen pipeline to the water inlet of the leaking cooling wall. Step 3: During the process of the blast furnace switching to the re-entry state, the air volume entering the furnace is monitored in real time, and the opening of the clean gas valve on the clean gas pipeline and the nitrogen valve on the nitrogen pipeline are adjusted in stages according to the change of the air volume entering the furnace to maintain pressure and cool. Step 4: When the furnace air volume reaches the furnace air volume value during normal production, calculate the net gas target flow rate of a single water-leaking cooling wall, and adjust the corresponding net gas flow rate and the final nitrogen target flow rate according to the net gas target flow rate. Step 5: Under full-air steady-state operation, monitor in real time the temperature of the clean gas introduced into the water-cooled wall and the temperature of the inner surface of the water-cooled wall, and adaptively adjust the opening of the clean gas valve and the nitrogen valve based on the temperature feedback values.

[0007] Preferably, in step one, water control treatment and gas overflow monitoring are carried out on the leaking cooling wall, and the overflowed gas is collected for composition detection. Specifically, this includes: gradually reducing the opening of the water inlet valve on the original water inlet pipe of the leaking cooling wall in increments of 5%, and monitoring the gas concentration discharged from the drainage pipe in real time. When the concentration value displayed by the gas alarm device exceeds 160ppm, open the collection bag valve at the gas collection bag inlet, and continue to close the water inlet valve until the detection value of the gas alarm device exceeds the upper limit of the range. Maintain the current opening state of the water inlet valve for 2 to 3 minutes to collect gas. If the gas alarm device does not issue an alarm signal during the process of gradually closing the opening of the water inlet valve, then stop closing the water inlet valve and control the opening of the water inlet valve to remain at 20% or above; obtain the actual carbon monoxide content in the gas collected in the gas collection bag with a capacity of 0.2 cubic meters to 0.3 cubic meters.

[0008] Preferably, in step two, after confirming that the carbon monoxide content in the gas meets the set conditions, the blast furnace is controlled to enter a shutdown state, the water outlet of the water-leaking cooling wall is sealed, and the high-pressure clean gas in the clean gas pipeline and the high-pressure nitrogen in the nitrogen pipeline are connected to the water inlet of the water-leaking cooling wall. Specifically, when the carbon monoxide content in the collected gas is in the range of 25% to 30%, it is determined that the area where the water-leaking cooling wall is located is in an indirect reduction reaction state, and the carbon monoxide content in the gas is confirmed to meet the set conditions. The blast furnace system is controlled to enter a shutdown state, and the water outlet of the leaking cooling wall is strictly sealed; the clean gas recovered from the top of the blast furnace is introduced into the clean gas pipeline through the pipeline after the bag filter dust collector, and the pressure of the pressurized clean gas is set to be more than 100 kPa higher than the blast furnace inlet air pressure during normal blast furnace production. High-pressure nitrogen is introduced into the nitrogen pipeline, and the pressurized clean gas pipeline and the high-pressure nitrogen pipeline are connected to the water inlet of the leaking cooling wall via a water inlet three-way valve.

[0009] Preferably, in step three, during the process of the blast furnace switching to the re-blast state, the air volume entering the furnace is monitored in real time, and the opening of the clean gas valve on the clean gas pipeline and the nitrogen valve on the nitrogen pipeline is adjusted in stages according to the change of the air volume entering the furnace for pressure holding and cooling. Specifically, this includes: when hot air is not introduced into the blast furnace tuyeres, the nitrogen valve is opened to control the nitrogen pressure entering the cavity inside the water-cooled wall to be greater than 500 kPa for pressure holding and cooling. When the blast furnace air volume increases to 20% of the total blast furnace air volume during normal production, the blast furnace priming gas operation is started. When the furnace air volume reaches 50% of the normal furnace air volume during production, or when the furnace air volume reaches more than 1,000 cubic meters per minute and the furnace charge moves downward, clean coal gas is introduced into the interior of the water-cooled wall, and the opening of the clean coal gas valve is gradually increased from zero to 20%, while the opening of the nitrogen valve is gradually decreased from fully open to 20%.

[0010] Preferably, in step four, the net gas target flow rate of a single water-cooled wall is calculated, and the corresponding net gas flow rate and the final nitrogen target flow rate are adjusted according to the net gas target flow rate. Specifically, this includes: obtaining the operating parameters and airflow distribution model parameters of the blast furnace body, specifically obtaining the total air volume of the furnace during normal production and the air-gas conversion coefficient, multiplying the total air volume of the furnace during normal production by the air-gas conversion coefficient, and calculating the total gas flow rate in the upper part of the blast furnace. The blast furnace mid-repair airflow index and edge airflow distribution weight in the blast furnace airflow distribution model are obtained. The obtained blast furnace mid-repair airflow index and the edge airflow distribution weight are added together to obtain the total airflow weight coefficient. The obtained total gas flow in the upper part of the blast furnace is multiplied by the edge airflow distribution weight and divided by the total airflow weight coefficient to calculate the total gas flow in the blast furnace edge region. Obtain the total number of cooling wall blocks arranged in a single ring around the blast furnace body. Divide the calculated total gas flow rate of the blast furnace edge region by the total number of cooling wall blocks arranged in a single ring around the blast furnace body to calculate the target net gas flow rate required for a single water-leaking cooling wall. Based on the physical benchmark that the natural nitrogen content in the blast furnace net gas is approximately 50%, adjust the opening of the nitrogen valve to adjust the final target nitrogen flow rate into the water-leaking cooling wall to the same level as the target net gas flow rate.

[0011] Preferably, in step five, the opening of the clean gas valve and the nitrogen valve is adaptively adjusted based on the temperature feedback value. When adjusting for the overheating state of the gas, the specific steps include: setting the normal operating temperature range of the clean gas to 100 degrees Celsius to 250 degrees Celsius; when the monitored temperature value of the clean gas is greater than 200 degrees Celsius, it is determined that the cooling capacity of the clean gas introduced into the water-leaking cooling wall is insufficient. The target nitrogen flow rate that needs to be adjusted is calculated based on the temperature compensation relationship. The target nitrogen flow rate is equal to the net coal gas flow rate plus the compensation flow rate. The compensation flow rate is the product of the net coal gas flow rate and the temperature coefficient. The temperature coefficient is calculated by subtracting 200 from the real-time monitored net coal gas temperature and dividing the difference by the set maximum safe temperature limit of the cooling wall. The maximum safe temperature limit of the cooling wall is set to 150. Control the opening of the nitrogen valve to adjust the actual nitrogen flow rate at a temperature of 20 degrees Celsius to the calculated target nitrogen flow rate value.

[0012] Preferably, in step five, the opening of the clean gas valve and the nitrogen valve is adaptively adjusted according to the temperature feedback value. When adjusting the temperature rise of the inner surface of the cooling wall, this specifically includes setting the maximum safe temperature limit of the cooling wall to 150 degrees Celsius. When the inner surface temperature of the water-cooled wall is greater than 150 degrees Celsius and the temperature of the clean gas is less than or equal to 150 degrees Celsius, the opening of the clean gas valve is increased to increase the flow rate of the clean gas. When the inner surface temperature of the water-cooled wall is greater than 150 degrees Celsius and the temperature of the clean gas is greater than 150 degrees Celsius, it is forbidden to increase the flow rate of clean gas. Only the opening of the nitrogen valve should be increased to increase the nitrogen flow rate.

[0013] Preferably, after step five, the method further includes: initiating an intervention operation or extreme protection operation for the blast furnace edge charging when the temperature exceeds the safety limit. Specifically, this includes: when the nitrogen valve is 100% open and the inner surface temperature of the leaking cooling wall is still greater than 150 degrees Celsius, determining that the gas flow at the edge of the furnace in the area where the leaking cooling wall is located is abnormally developing, and controlling the blast furnace charging system to increase the number of edge ore charging rings in a pattern of increasing by 0.5 to 1 ring. The distance the furnace charge moves downward is continuously tracked, starting from the first batch of furnace charge with increased edge ore distribution rings. When the first batch of furnace charge moves downward to the physical elevation of the leaking cooling wall, the original distribution system is restored. When the inner surface temperature of the water-leaking cooling wall rapidly rises to 100 degrees Celsius or above, an extreme protection operation is performed, immediately closing the clean gas valve to cut off the clean gas input, and simultaneously controlling the nitrogen valve to continuously supply high-pressure nitrogen into the interior of the water-leaking cooling wall.

[0014] Preferably, the water-leaking cooling wall in step one is a cooling wall located in the medium-temperature or low-temperature zone, and its specific position elevation range on the blast furnace body includes: the waist area of ​​the blast furnace, the lower part of the furnace body, and the upper part of the furnace body.

[0015] A gas ventilation and pressure maintenance system for a water-leaking cooling wall on the upper part of a blast furnace body includes: a gas monitoring and water control module, including a water inlet valve installed on the original water inlet pipe of the water-leaking cooling wall, a gas alarm device on the drainage pipe, and a gas collection bag with a collection bag valve at the gas inlet. Used to perform water control and gas overflow monitoring after water leakage is detected, and to collect the overflow gas; the gas path reconstruction execution module includes a three-way interface set at the water outlet pipe of the water leakage cooling wall, a water inlet three-way valve at the water inlet end, and a clean gas pipeline and a nitrogen pipeline respectively connected to the water inlet three-way valve. Used to seal the water outlet of the leaking cooling wall in the off-peak state, and to connect the high-pressure clean coal gas in the clean coal gas pipeline and the high-pressure nitrogen in the nitrogen pipeline to the water inlet of the leaking cooling wall. The valve follow-up control module is used to adjust the opening degree of the clean gas valve on the clean gas pipeline and the nitrogen valve on the nitrogen pipeline in stages according to the real-time monitored changes in the furnace air volume during the process of the blast furnace switching to the re-entry state. The target flow rate calculation module is used to calculate the net gas target flow rate of a single water-leaking cooling wall when the furnace air volume reaches the value of the total furnace air volume during normal production, and adjust the corresponding net gas flow rate and the final nitrogen target flow rate according to the net gas target flow rate. The temperature monitoring and adaptive adjustment module includes a gas temperature sensor installed on the clean gas pipeline and a cooling wall temperature sensor installed on the water-leaking cooling wall near the inner surface of the furnace skin. It is used to adaptively adjust the opening of the clean gas valve and the nitrogen valve based on the temperature feedback value, and to trigger the feeding system to perform intervention operation or start extreme protection operation when the temperature exceeds the safety limit.

[0016] This invention provides a method for maintaining pressure by venting the cooling wall above the blast furnace body where water leaks. It has the following beneficial effects: 1. This invention achieves precise adaptation of pressure-maintaining cooling for water-leaking cooling walls by constructing a multi-source airflow follow-up control and target flow calculation mechanism. During the blast furnace re-blasting stage, the method adjusts the opening of the clean gas and nitrogen valves in stages according to the blast furnace airflow node. Under full-blast steady state, the target flow rates of clean gas and nitrogen for a single cooling wall are calculated by combining the parameters of the blast furnace airflow distribution model and the air-gas conversion coefficient. This dynamic control and quantitative allocation based on actual operating conditions avoids the problems of insufficient cooling or gas waste caused by blindly ventilating based on experience in the traditional method. While effectively preventing backflow of gas in the furnace, it also ensures the stability of the internal pressure of the cooling wall.

[0017] 2. This invention introduces an adaptive heat exchange regulation logic based on multi-point temperature monitoring, which effectively extends the service life of the leaking cooling wall. By synchronously collecting the temperature of the clean gas introduced into the cooling wall and the temperature of the inner surface of the cooling wall, when the gas overheating or the temperature rise of the inner surface of the cooling wall is abnormal, the target nitrogen flow rate is calculated according to the set temperature compensation relationship, and the input ratio of room temperature high pressure nitrogen is increased in a targeted manner. This mechanism can quickly make up for the deficiency of insufficient cooling capacity of the clean gas itself, prevent the high temperature gas from causing secondary thermal stress damage to the cooling wall body, and maintain the cooling wall operating within the set safe temperature limit.

[0018] 3. This invention establishes a cross-system edge charging intervention and extreme protection strategy, which suppresses the abnormal development of blast furnace edge airflow from the source. When the nitrogen valve is fully open and the inner surface temperature of the cooling wall still exceeds the safety limit, the method directly links the blast furnace charging system to increase the number of edge ore charging rings, using the physical blocking effect of the downward movement of the furnace charge to suppress the high-temperature edge airflow. In extreme conditions where the inner surface temperature rises rapidly to over 300 degrees Celsius, the input of combustible clean coal gas is forcibly cut off and a pure nitrogen emergency cooling mode is entered. This not only improves the survivability of the leaking cooling wall under harsh conditions, but also significantly improves the overall safety of blast furnace production. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the blast furnace water leakage cooling wall ventilation and pressure maintenance system of the present invention; Figure 2 This is a schematic diagram of the gas path reconstruction during blast furnace shutdown according to the present invention.

[0020] The components include: 1. Water-leaking cooling wall; 2. T-junction; 3. Drainage pipe; 4. Gas alarm device; 5. Gas collection bag; 6. Collection bag valve; 7. Water inlet valve; 8. Clean gas pipe; 9. Clean gas valve; 10. Nitrogen pipe; 11. Nitrogen valve; 12. Gas temperature sensor; 13. Cooling wall temperature sensor; and 14. Water inlet t-junction valve. Detailed Implementation

[0021] The technical solutions in 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. Example

[0022] See attached document Figure 1 -Appendix Figure 2 The present invention provides a method for ventilating and pressurizing a water-leaking cooling wall on the upper part of a blast furnace. The hardware system for executing the method may include: a water-leaking cooling wall 1, a three-way interface 2, a drainage pipe 3, a gas alarm device 4, a gas collection bag 5, a collection bag valve 6, a water inlet valve 7, a clean gas pipe 8, a clean gas valve 9, a nitrogen pipe 10, a nitrogen valve 11, a gas temperature sensor 12, a cooling wall temperature sensor 13, and a water inlet three-way valve 14.

[0023] The tee connector 2 is installed at the outlet pipe of the water-leaking cooling wall 1. The first end of the tee connector 2 is connected to the internal cavity of the water-leaking cooling wall 1, the second end of the tee connector 2 is connected to the drain pipe 3, and the third end of the tee connector 2 is connected to the gas collection bag 5.

[0024] A gas alarm device 4 is installed on the drainage pipe 3 to detect the concentration of gas discharged with the water. A gas collection bag valve 6 is installed at the gas inlet of the gas collection bag 5 to control the opening and closing of the gas collection bag 5. An inlet valve 7 is installed on the original water inlet pipe of the leaking cooling wall 1 to regulate the input of cooling water.

[0025] The water inlet of the water-leaking cooling wall 1 is connected to a clean gas pipeline 8 and a nitrogen pipeline 10 via a water inlet three-way valve 14. The clean gas pipeline 8 is equipped with a clean gas valve 9 and a gas temperature sensor 12, configured to introduce blast furnace top gas after bag filter dust removal and monitor the gas temperature in the clean gas pipeline 8. The nitrogen pipeline 10 is equipped with a nitrogen valve 11, configured to introduce high-pressure nitrogen. A cooling wall temperature sensor 13 is installed on the inner surface of the water-leaking cooling wall 1 near the furnace skin for real-time acquisition of wall surface temperature data.

[0026] Based on the above system architecture, the blast furnace upper water-leaking cooling wall ventilation and pressure maintenance method provided by the present invention includes the following steps: First, the location of the cooling wall where the blast furnace is leaking water is marked. After determining that the leaking cooling wall 1 is located in the section above the furnace waist, the water inlet valve 7 is adjusted to gradually reduce the water inlet flow. The gas alarm device 4 monitors the gas concentration in the drainage pipe 3 in real time. When the concentration reaches the set threshold, the collection bag valve 6 is opened to allow the gas overflowing from the furnace to enter the gas collection bag 5.

[0027] Subsequently, the gas composition in the gas collection bag 5 was tested. After confirming that the carbon monoxide concentration met the set conditions, the gas path reconstruction operation was performed. Under the blast furnace shutdown state, the water outlet of the water-leaking cooling wall 1 was blocked, and the pressurized clean gas pipeline 8 and the high-pressure nitrogen pipeline 10 were connected to the water inlet of the water-leaking cooling wall 1 via the water inlet three-way valve 14.

[0028] During the process of switching the blast furnace from shutdown to restart, the opening of the clean gas valve 9 and the nitrogen valve 11 are adjusted synchronously according to the real-time change ratio of the blast furnace air volume, and gas is introduced into the interior of the water-cooled wall 1 for pressure holding and cooling.

[0029] After the blast furnace enters the full-air steady-state operation stage, the opening of the clean gas valve 9 and the nitrogen valve 11 is adjusted according to the temperature feedback values ​​collected by the gas temperature sensor 12 and the cooling wall temperature sensor 13 to adjust the flow ratio of the two gases. When the temperature exceeds the safety limit, the number of ore charging rings at the top of the blast furnace is adjusted to suppress the development of edge airflow and maintain the safe operation of the water-leaking cooling wall 1.

[0030] See attached document Figure 1 -Appendix Figure 2 This invention provides a method for ventilating and pressurizing the upper water-leaking cooling wall of a blast furnace, including the following steps for assessing the condition of the water-leaking cooling wall and controlling water flow: The vertical height of the blast furnace body is divided according to the number of cooling wall layers. The elevation of the cooling wall where water leakage occurs is marked and recorded. Based on the temperature range of the furnace body inside the blast furnace, the vertical height of the blast furnace is divided into high temperature zone, medium temperature zone and low temperature zone.

[0031] The hearth and belly regions of the blast furnace are designated as high-temperature zones, the waist and lower body regions as medium-temperature zones, and the upper body region as low-temperature zones.

[0032] When the leaking cooling wall is located in the high-temperature section of the hearth or belly area, the venting and pressure-maintaining operation is not performed on the leaking cooling wall. When the leaking cooling wall is located in the waist or above area, i.e. in the medium-temperature or low-temperature section, the cooling wall is identified as the target leaking cooling wall 1, and water control treatment is performed on the target leaking cooling wall 1.

[0033] During the water control process, adjust the water inlet valve 7 installed on the water inlet pipe of the target leaking cooling wall 1, and set the opening value of the fully open water inlet valve 7 to 100%.

[0034] Operate the inlet valve 7 and gradually reduce its opening by 5% at a time. During the process of gradually reducing the opening of the inlet valve 7, the gas alarm device 4 installed on the drain pipe 3 monitors the state of the medium discharged from the drain pipe 3 in real time.

[0035] When the gas alarm device 4 at the drainage pipe 3 issues an alarm signal, it is determined that the gas inside the blast furnace overflows into the internal cavity of the target water-leaking cooling wall 1 through the water leakage point and is discharged through the drainage pipe 3.

[0036] If the gas alarm device 4 does not issue an alarm signal during the process of gradually closing the opening of the water inlet valve 7, it indicates that the water leakage is small and the gas supply conditions have not been met. At this time, stop closing the water inlet valve 7 and keep the opening of the water inlet valve 7 at 20% or above.

[0037] By maintaining the inlet valve 7 at an opening of no less than 20%, the cooling water circulation inside the target leaking cooling wall 1 is maintained, and it is prohibited to cut off the water supply to the target leaking cooling wall 1 that has not met the ventilation conditions.

[0038] See attached document Figure 1 -Appendix Figure 2 The blast furnace upper water leakage cooling wall ventilation and pressure maintenance method provided by the present invention, in the gas overflow monitoring and concentration threshold calibration stage, may include the following specific operation steps: During the process of gradually closing the water inlet valve 7, the gas alarm device 4 monitors the gas concentration at the drainage pipe 3 in real time. When the concentration value displayed by the gas alarm device 4 exceeds 160ppm, it is determined that the gas inside the blast furnace has overcome the water seal resistance and begun to overflow stably. At this time, the gas collection bag valve 6 at the gas collection bag 5 inlet is opened, so that the gas overflowing from the leaking cooling wall 1 enters the gas collection bag 5.

[0039] After opening the collection bag valve 6, continue to close the opening of the water inlet valve 7 by 5% each time. When the detection value of the gas alarm device 4 exceeds the upper limit of the range and cannot display the specific gas concentration value, stop closing the water inlet valve 7.

[0040] After stopping the operation, keep the inlet valve 7 at its current opening position for 2 to 3 minutes to allow the overflowing gas to be fully collected in the gas collection bag 5, and set the volume of the gas collection bag 5 to 0.2 cubic meters to 0.3 cubic meters.

[0041] After the gas collection is completed, the valve 6 of the collection bag is closed, and the gas in the gas collection bag 5 is analyzed to detect the concentration of carbon monoxide and carbon dioxide in the gas components, and to obtain the actual content of carbon monoxide in the collected gas. At this time, the content of carbon monoxide in the collected gas is much greater than the content of carbon dioxide.

[0042] The state is determined based on the detected carbon monoxide content. When the carbon monoxide content in the collected gas is higher than 30%, it is determined that no indirect reduction reaction has occurred in the area where the water-leaking cooling wall 1 is located. When the carbon monoxide content in the collected gas is lower than 25%, it is determined that the indirect reduction reaction in the area where the water-leaking cooling wall 1 is located has ended.

[0043] When the carbon monoxide content in the collected gas is between 25% and 30%, it is determined that the area where the leaking cooling wall 1 is located is in an indirect reduction reaction state. And when it is confirmed that the carbon monoxide content meets the requirements of 25% to 30%, it is determined that the target leaking cooling wall 1 meets the requirements for ventilation and pressure maintenance, and enters the gas path reconstruction and ventilation operation stage.

[0044] See attached document Figure 1 -Appendix Figure 2 The multi-source gas path reconstruction steps of the blast furnace upper water-leaking cooling wall ventilation and pressure maintenance operation method provided by the present invention under the shutdown state include: after confirming that the carbon monoxide concentration in the gas collection bag 5 meets the ventilation and pressure maintenance requirements, controlling the blast furnace system to enter the shutdown state, and sealing the water outlet of the water-leaking cooling wall 1 under the shutdown state. After sealing the water outlet of the water-leaking cooling wall 1, the clean coal gas recovered from the top of the blast furnace is introduced into the clean coal gas pipeline 8 through the pipeline after the bag dust collector. At the same time, the clean coal gas in the clean coal gas pipeline 8 is pressurized during the diversion process. The pressurized clean coal gas pressure is set to be more than 100 kPa higher than the furnace air pressure during normal blast furnace production. Then, while pressurizing and diverting the clean coal gas in the clean coal gas pipeline 8, high-pressure nitrogen is introduced into the nitrogen pipeline 10. The pressurized clean coal gas pipeline 8 and the high-pressure nitrogen pipeline 10 are connected to the water inlet of the water-leaking cooling wall 1 through the water inlet three-way valve 14.

[0045] See attached document Figure 1 -Appendix Figure 2The blast furnace upper water-cooled wall ventilation and pressure-maintaining operation method provided by this invention includes the following steps in the air volume and gas source follow-up control during the blast furnace restart transition period: When the blast furnace transitions from a shutdown state to a restart state and hot air is not introduced into the blast furnace tuyeres, the nitrogen valve 11 on the nitrogen pipeline 10 is opened to control the nitrogen pressure entering the internal cavity of the water-cooled wall 1 to be greater than 500 kPa, thus maintaining pressure and cooling the water-cooled wall 1. Simultaneously, as the blast furnace restart process progresses, the blast furnace feed air volume is monitored in real time. When the blast furnace feed air volume increases to 20% of the normal production period's total feed air volume, the blast furnace priming gas operation is initiated. Continuously monitor the blast furnace air volume and the state of the furnace charge. When the blast furnace air volume reaches 50% of the normal blast furnace air volume during production, or when the blast furnace air volume reaches more than 1,000 cubic meters per minute and the furnace charge moves downward, open the clean gas valve 9 on the clean gas pipeline 8 to introduce clean gas into the water-cooled wall 1. During the process of introducing clean gas, control the opening of the clean gas valve 9 from zero to 20%, and at the same time control the opening of the nitrogen valve 11 from fully open to 20%, and finally keep the opening of both the clean gas valve 9 and the nitrogen valve 11 at 20%.

[0046] See attached document Figure 1 -Appendix Figure 2 The target flow calculation steps of the blast furnace upper water-cooled wall ventilation and pressure-maintaining operation method provided by the present invention under steady-state full-blast conditions include: as the blast furnace blasting process progresses, when the blast furnace feed air volume reaches the normal production period's full-blast feed air volume value, adjusting the rise of the nitrogen valve on the nitrogen pipeline 10 to control the initial nitrogen flow rate into the water-cooled wall within the range of 100 to 200 cubic meters per hour; and simultaneously calculating the net gas target flow rate Q of the water-cooled wall based on the blast furnace's operating parameters. G Specifically, this involves obtaining the total air volume V entering the furnace during normal production. normal And the wind-air conversion coefficient α, through the formula V total_gas =V normal The total gas flow V in the upper part of the blast furnace is calculated by ×α. total_gas This allows us to obtain the blast furnace overhaul airflow index I in the blast furnace airflow distribution model. repair and edge airflow distribution weight I edge Through formula I total =I repair +I edge The total airflow weighting coefficient I is calculated. t otal, and through the formula The total gas flow V in the blast furnace edge region was calculated. edge Then, the total number N of cooling wall blocks arranged in a single ring around the blast furnace body is obtained. stawe Through formula The target net gas flow rate Q required to be allocated to a single leaky cooling wall was calculated. G And based on the target net gas flow rate Q G Adjust the clean gas valve 9 on the clean gas pipeline 8, and finally obtain the calculated target flow rate Q of the clean gas based on the physical benchmark that the natural nitrogen content in the blast furnace clean gas is about 50%. G The value is used to synchronously adjust the opening of the nitrogen valve 11 on the nitrogen pipeline 10, thereby increasing the final target flow rate Q of nitrogen gas supplied to the water-cooled wall. N Adjust to match the target flow rate Q of the clean gas G The same numerical level.

[0047] See attached document Figure 1 -Appendix Figure 2 The adjustment steps of the blast furnace upper water-cooled wall ventilation and pressure-maintaining operation method provided by the present invention under the condition of gas overheating include: when the blast furnace is in a full-air steady-state operation, the gas temperature sensor 12 installed on the clean gas pipeline 8 acquires the clean gas temperature data entering the water-cooled wall in real time, and compares the acquired clean gas temperature data with the set temperature parameter value. The normal operating temperature range of the clean gas is set to 100 degrees Celsius to 250 degrees Celsius, and when the clean gas temperature value T acquired by the gas temperature sensor 12 is... G When the temperature exceeds 200 degrees Celsius, it is determined that the cooling capacity of the clean coal gas entering the water-leaking cooling wall 1 is insufficient. Therefore, after determining that the temperature of the clean coal gas exceeds 200 degrees Celsius, heat exchange is regulated by increasing the proportion of high-pressure nitrogen. The temperature of the nitrogen introduced into the nitrogen pipeline 10 is set to 20 degrees Celsius, and then the current flow rate Q of the clean coal gas flowing into the water-leaking cooling wall 1 is obtained. G Based on the temperature compensation relationship, the target nitrogen flow rate Q that needs to be adjusted is calculated. N_new Through formula Calculations were performed, in which T max To set the maximum safe temperature limit for the cooling wall, set the maximum safe temperature limit T for the cooling wall. max The value is 150, and the final calculated target nitrogen flow rate Q is obtained. N_new Then, control the opening of the nitrogen valve 11 on the nitrogen pipeline 10. By opening the nitrogen valve, adjust the actual nitrogen flow rate into the leaking cooling wall to the calculated target nitrogen flow rate value Q. N_new Increase the proportion of room temperature nitrogen input to maintain a safe temperature for the leaking cooling wall.

[0048] See attached document Figure 1 -Appendix Figure 2The method for maintaining pressure and ventilation of the upper water-cooled wall of a blast furnace provided by this invention includes the following steps in the directional control stage of the temperature rise on the inner surface of the cooling wall: During steady-state operation, a cooling wall temperature sensor 13 installed near the inner surface of the furnace shell 1 monitors the inner surface temperature data of the water-cooled wall 1 in real time; simultaneously, a gas temperature sensor 12 installed on the clean gas pipeline 8 acquires the temperature data of the clean gas entering the water-cooled wall 1 in real time; and the acquired inner surface temperature data of the water-cooled wall 1 is compared with a set maximum safe temperature limit for the cooling wall. The maximum safe temperature limit for the cooling wall is set to 150 degrees Celsius. Furthermore, when the inner surface temperature value monitored by the cooling wall temperature sensor 13 is greater than 150 degrees Celsius, and the clean gas temperature value monitored by the gas temperature sensor 12 is less than or equal to 150 degrees Celsius... If the clean coal gas has sufficient cooling capacity, then under the above conditions, the flow rate of clean coal gas is increased first, that is, the opening of the clean coal gas valve 9 on the clean coal gas pipeline 8 is increased to increase the flow rate of clean coal gas into the water-cooled wall 1, so as to reduce the inner surface temperature of the water-cooled wall 1. When the inner surface temperature value monitored by the cooling wall temperature sensor 13 is greater than 150 degrees Celsius, and the clean coal gas temperature value monitored by the coal gas temperature sensor 12 is greater than 150 degrees Celsius, it is determined that both the clean coal gas and the water-cooled wall 1 are in a high-temperature state, and it is prohibited to increase the flow rate of clean coal gas. At the same time, under the condition that it is prohibited to increase the flow rate of clean coal gas, cooling is carried out only by increasing the amount of room temperature nitrogen, that is, the opening of the nitrogen valve 11 on the nitrogen pipeline 10 is increased to increase the flow rate of nitrogen into the water-cooled wall 1, so as to maintain the safe operation of the water-cooled wall 1.

[0049] See attached document Figure 1 -Appendix Figure 2The blast furnace upper water-cooled wall ventilation and pressure-maintaining operation method provided by this invention includes the following steps in the cross-system edge charging intervention and extreme protection stage: when the nitrogen valve 11 on the nitrogen pipeline 10 is 100% open, and the inner surface temperature value monitored by the cooling wall temperature sensor 13 installed near the inner surface of the furnace skin of the water-cooled wall 1 is still greater than 150 degrees Celsius, it is determined that the edge airflow in the area where the water-cooled wall 1 is located is abnormally developed, and then the blast furnace charging intervention operation is initiated. That is, according to the preset position mark of the water-cooled wall 1 in the circumferential direction of the blast furnace, the blast furnace charging system is controlled to adjust the edge charging parameters, and the number of edge ore charging rings is increased in a pattern of increasing by 0.5 rings to 1 ring, so as to suppress... The system controls the airflow at the edge of the furnace and continuously tracks the distance the charge moves downward. Starting from the first batch of charge with increased edge ore charging rings, when the first batch of charge moves downward exactly to the physical elevation of the water-cooled wall 1, the system controls the blast furnace charging system to restore the original charging regime. In addition, if an abnormal state occurs in the blast furnace production, causing the inner surface temperature of the water-cooled wall 1 to rise rapidly to 300 degrees Celsius or above, an extreme protection operation is executed. The clean gas valve 9 on the clean gas pipeline 8 is immediately closed to cut off the input of combustible clean gas, and the nitrogen valve 11 on the nitrogen pipeline 10 is simultaneously controlled to continuously supply high-pressure nitrogen into the interior of the water-cooled wall 1, entering an emergency mode that relies solely on nitrogen for pressure holding and cooling.

[0050] See attached document Figure 1 -Appendix Figure 2The deductive steps of the blast furnace upper water leakage cooling wall ventilation and pressure maintenance operation method provided by the present invention in a specific embodiment include: in actual blast furnace production application, the normal production period is set to a total air volume of 5800 cubic meters per minute, and the total number of cooling wall blocks arranged in a single ring around the blast furnace body is 30. After detecting water leakage in the upper cooling wall of the blast furnace body, the cooling wall is identified as the water leakage cooling wall 1. The water inlet valve 7 is operated to gradually control the water flow, and the gas concentration is monitored simultaneously using the gas alarm device 4. The gas collection bag valve 6 is opened to collect the gas and measure the gas concentration. The carbon monoxide content in the collection bag 5 is between 25% and 30%, confirming that the area where the water-leaking cooling wall 1 is located has the conditions for ventilation and pressure maintenance. Therefore, the blast furnace system is controlled to enter a shutdown state, the water outlet of the water-leaking cooling wall 1 is sealed, and the clean gas pipeline 8 and nitrogen pipeline 10 are connected to the water inlet of the water-leaking cooling wall 1 through the inlet three-way valve 14. During the blast furnace restart phase, the clean gas valve 9 and nitrogen valve 11 are adjusted in stages according to the changes in the blast furnace air volume. Subsequently, when the blast furnace air volume recovers to a full blast state of 5800 cubic meters per minute, the system's preset air volume is obtained. A conversion factor of 1.5 was used. Multiplying this factor by the normal blast furnace airflow during production yielded a total gas flow rate of 8700 cubic meters per minute in the upper part of the blast furnace. Simultaneously, blast furnace airflow distribution model data was acquired. The blast furnace overhaul airflow index was set to 1.0, and the edge airflow distribution weight to 0.8. Adding these two values ​​resulted in a total airflow weight coefficient of 1.8. The total gas flow rate in the upper part of the blast furnace was then multiplied by the edge airflow distribution weight and divided by the total airflow weight coefficient, resulting in a total gas flow rate of 3867 cubic meters per minute in the blast furnace edge region. This calculated value was then... The total gas flow rate in the blast furnace edge area is divided by the total number of cooling wall blocks arranged in a single ring around the blast furnace body, which is 30. The net gas target flow rate of a single water-leaking cooling wall 1 is calculated to be 129 cubic meters per minute. Based on the calculation results, the net gas valve 9 is controlled to adjust the gas flow rate of the net gas pipeline 8 to 129 cubic meters per minute. At the same time, based on the natural nitrogen ratio in the net gas, the nitrogen valve 11 is controlled to adjust the final nitrogen target flow rate of the nitrogen pipeline 10 into the water-leaking cooling wall 1 to 129 cubic meters per minute, thus completing the calculation and input of the multi-source gas flow rate benchmark.

[0051] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for maintaining pressure by venting air through the upper water-cooled wall of a blast furnace, characterized in that, Includes the following steps: Step 1: After detecting the water leak, water control treatment and gas overflow monitoring are carried out on the leaking cooling wall (1), and the overflowing gas is collected for composition analysis; Step 2: After confirming that the carbon monoxide content in the gas meets the set conditions, control the blast furnace to enter the shutdown state, seal the water outlet of the water-leaking cooling wall (1), and connect the high-pressure clean gas in the clean gas pipeline (8) and the high-pressure nitrogen in the nitrogen pipeline (10) to the water inlet of the water-leaking cooling wall (1). Step 3: During the process of the blast furnace switching to the re-blast state, the air volume entering the furnace is monitored in real time, and the opening of the clean gas valve (9) on the clean gas pipeline (8) and the nitrogen valve (11) on the nitrogen pipeline (10) are adjusted in stages according to the change of the air volume entering the furnace to maintain pressure and cool. Step 4: When the furnace air volume reaches the value of the total furnace air volume during normal production, calculate the net gas target flow rate of a single water-leaking cooling wall (1), and adjust the corresponding net gas flow rate and the final nitrogen target flow rate according to the net gas target flow rate. Step 5: Under full-air steady-state operation, monitor the temperature of the clean gas entering the water-cooled wall (1) and the temperature of the inner surface of the water-cooled wall (1) in real time, and adjust the opening of the clean gas valve (9) and the nitrogen valve (11) according to the temperature feedback values.

2. The method for maintaining pressure and ventilation of the upper water-cooled wall of a blast furnace according to claim 1, characterized in that, In step one, water control treatment and gas overflow monitoring are carried out on the leaking cooling wall (1), and the overflowing gas is collected for component detection. Specifically, the opening of the water inlet valve (7) on the original water inlet pipe of the leaking cooling wall (1) is gradually reduced by 5% each time, and the gas concentration discharged from the drainage pipe (3) is monitored in real time. When the concentration value displayed by the gas alarm device (4) exceeds 160ppm, open the gas collection bag valve (6) at the gas inlet of the gas collection bag (5), and continue to close the water inlet valve (7) until the detection value of the gas alarm device (4) exceeds the upper limit of the range. Keep the current opening state of the water inlet valve (7) for 2 to 3 minutes to collect gas. If the gas alarm device (4) does not issue an alarm signal during the operation of gradually closing the opening of the water inlet valve (7), then stop closing the water inlet valve (7) and control the opening of the water inlet valve (7) to be maintained at 20% or above; obtain the actual carbon monoxide content in the gas collected in the gas collection bag (5) with a capacity of 0.2 cubic meters to 0.3 cubic meters.

3. The method for maintaining pressure and ventilation of the upper water-cooled wall of a blast furnace according to claim 1, characterized in that, In step two, after confirming that the carbon monoxide content in the gas meets the set conditions, the blast furnace is controlled to enter the shutdown state, the water outlet of the water-leaking cooling wall (1) is blocked, and the high-pressure clean gas in the clean gas pipeline (8) and the high-pressure nitrogen in the nitrogen pipeline (10) are connected to the water inlet of the water-leaking cooling wall (1). Specifically, when the carbon monoxide content in the collected gas is in the range of 25% to 30%, it is determined that the area where the water-leaking cooling wall (1) is located is in an indirect reduction reaction state, and the carbon monoxide content in the gas meets the set conditions. Control the blast furnace system to enter the shutdown state, strictly seal the water outlet of the water-leaking cooling wall (1); introduce the clean coal gas recovered from the top of the blast furnace into the clean coal gas pipeline (8) through the pipeline after the bag dust collector, and set the pressure of the pressurized clean coal gas to be more than 100 kPa greater than the blast furnace inlet air pressure during normal blast furnace production. High-pressure nitrogen is introduced into the nitrogen pipeline (10), and the pressurized clean gas pipeline (8) and the high-pressure nitrogen pipeline (10) are connected together to the water inlet of the water-leaking cooling wall (1) via the water inlet three-way valve (14).

4. The method for maintaining pressure and ventilation of the upper water-cooled wall of a blast furnace according to claim 1, characterized in that, In step three, during the process of the blast furnace switching to the re-air state, the air volume entering the furnace is monitored in real time, and the opening of the clean gas valve (9) on the clean gas pipeline (8) and the nitrogen valve (11) on the nitrogen pipeline (10) are adjusted in stages according to the change of the air volume entering the furnace for pressure holding and cooling. Specifically, this includes: when hot air is not introduced into the blast furnace tuyeres, the nitrogen valve (11) is opened to control the nitrogen pressure entering the cavity inside the water-cooled wall (1) to be greater than 500 kPa for pressure holding and cooling. When the blast furnace air volume increases to 20% of the total blast furnace air volume during normal production, the blast furnace priming gas operation is started. When the furnace air volume reaches 50% of the normal furnace air volume during production, or when the furnace air volume reaches more than 1,000 cubic meters per minute and the furnace charge moves downward, clean coal gas is introduced into the interior of the water-cooled wall (1), and the opening of the clean coal gas valve (9) is gradually increased from zero to 20%, while the opening of the nitrogen valve (11) is gradually decreased from fully open to 20%.

5. The method for maintaining pressure and ventilation of the upper water-cooled wall of a blast furnace according to claim 1, characterized in that, In step four, the net gas target flow rate of a single water-cooled wall (1) is calculated, and the corresponding net gas flow rate and final nitrogen target flow rate are adjusted according to the net gas target flow rate. Specifically, the operating parameters and airflow distribution model parameters of the blast furnace body are obtained, specifically the value of the total air volume entering the furnace during normal production and the air-gas conversion coefficient are obtained. The total air volume entering the furnace during normal production is multiplied by the air-gas conversion coefficient to calculate the total gas flow rate in the upper part of the blast furnace. The blast furnace mid-repair airflow index and edge airflow distribution weight in the blast furnace airflow distribution model are obtained. The obtained blast furnace mid-repair airflow index and the edge airflow distribution weight are added together to obtain the total airflow weight coefficient. The obtained total gas flow in the upper part of the blast furnace is multiplied by the edge airflow distribution weight and divided by the total airflow weight coefficient to calculate the total gas flow in the blast furnace edge region. Obtain the total number of cooling wall blocks arranged in a single ring around the blast furnace body. Divide the total gas flow in the blast furnace edge region calculated by the total number of cooling wall blocks arranged in a single ring around the blast furnace body to calculate the target flow rate of net gas required for a single water-leaking cooling wall (1). Based on the physical benchmark that the natural nitrogen content in the blast furnace net gas is about 50%, adjust the opening of the nitrogen valve (11) to adjust the final target flow rate of nitrogen entering the water-leaking cooling wall (1) to the same numerical level as the target flow rate of net gas.

6. The method for maintaining pressure and ventilation of the upper water-cooled wall of a blast furnace body according to claim 1, characterized in that, In step five, the opening of the clean gas valve (9) and the nitrogen valve (11) is adaptively adjusted according to the temperature feedback value. When adjusting for the overheating state of the gas, the specific adjustment includes: setting the normal operating temperature range of the clean gas to 100 degrees Celsius to 250 degrees Celsius. When the monitored temperature value of the clean gas is greater than 200 degrees Celsius, it is determined that the cooling capacity of the clean gas entering the water-leaking cooling wall (1) is insufficient. The target nitrogen flow rate that needs to be adjusted is calculated based on the temperature compensation relationship. The target nitrogen flow rate is equal to the net coal gas flow rate plus the compensation flow rate. The compensation flow rate is the product of the net coal gas flow rate and the temperature coefficient. The temperature coefficient is calculated by subtracting 200 from the real-time monitored net coal gas temperature and dividing the difference by the set maximum safe temperature limit of the cooling wall. The maximum safe temperature limit of the cooling wall is set to 150. Control the opening of the nitrogen valve (11) to adjust the actual nitrogen flow rate at a temperature of 20 degrees Celsius to the calculated target nitrogen flow rate value.

7. The method for maintaining pressure and ventilation of the upper water-cooled wall of a blast furnace according to claim 1, characterized in that, In step five, the opening of the clean gas valve (9) and the nitrogen valve (11) is adaptively adjusted according to the temperature feedback value. When adjusting the temperature rise of the inner surface of the cooling wall, the specific adjustment includes setting the maximum safe temperature limit of the cooling wall to 150 degrees Celsius. When the inner surface temperature of the water-cooled wall (1) is greater than 150 degrees Celsius and the temperature of the clean gas is less than or equal to 150 degrees Celsius, the opening of the clean gas valve (9) is increased to increase the flow rate of the clean gas. When the inner surface temperature of the water-cooled wall (1) is greater than 150 degrees Celsius and the temperature of the clean gas is greater than 150 degrees Celsius, it is forbidden to increase the amount of clean gas entering the system. Instead, the opening of the nitrogen valve (11) should be increased to increase the nitrogen flow rate.

8. The method for maintaining pressure and ventilation of the upper water-cooled wall of a blast furnace according to claim 1, characterized in that, After step five, the following is also included: when the temperature exceeds the safety limit, the blast furnace edge charging intervention operation or extreme protection operation is initiated. Specifically, when the nitrogen valve (11) is 100% open and the inner surface temperature of the water-cooled wall (1) is still greater than 150 degrees Celsius, it is determined that the gas flow at the edge of the furnace in the area where the water-cooled wall (1) is located is abnormally developed, and the blast furnace charging system is controlled to increase the number of edge ore charging rings in a mode of increasing by 0.5 rings to 1 ring. The distance the furnace charge moves downward is continuously tracked. The calculation starts from the first batch of furnace charge with the increased number of edge ore feeding rings. When the first batch of furnace charge moves downward to the physical elevation of the leaking cooling wall (1), the original feeding system is restored. When the inner surface temperature of the water-leaking cooling wall (1) rises rapidly to 300 degrees Celsius or above, an extreme protection operation is performed, the clean gas valve (9) is immediately closed to cut off the clean gas input, and the nitrogen valve (11) is simultaneously controlled to continuously supply high-pressure nitrogen into the interior of the water-leaking cooling wall (1).

9. The method for maintaining pressure and ventilation of the upper water-cooled wall of a blast furnace according to claim 1, characterized in that, The water-leaking cooling wall (1) in step one is a cooling wall located in the medium-temperature or low-temperature zone. Its specific position and elevation range on the blast furnace body includes: the waist area of ​​the blast furnace, the lower part of the furnace body, and the upper part of the furnace body.

10. A blast furnace upper water-cooled wall ventilation and pressure-maintaining system, applied to a blast furnace including a water-cooled wall (1), for implementing a blast furnace upper water-cooled wall ventilation and pressure-maintaining operation method as described in any one of claims 1 to 9, characterized in that, include: The gas monitoring and water control module includes an inlet valve (7) installed on the original water inlet pipe of the leaking cooling wall (1), a gas alarm device (4) on the drainage pipe (3), and a gas collection bag (5) with a collection bag valve (6) at the gas inlet. Used to perform water control treatment and gas overflow monitoring after water leakage is detected, and to collect overflow gas; the gas path reconstruction execution module includes a three-way interface (2) set at the water outlet pipe of the water leakage cooling wall (1), a water inlet three-way valve (14) at the water inlet end, and a clean gas pipeline (8) and a nitrogen pipeline (10) respectively connected to the water inlet three-way valve (14). Used to seal the water outlet of the water-leaking cooling wall (1) in the off-peak state, and to connect the high-pressure clean gas in the clean gas pipeline (8) and the high-pressure nitrogen in the nitrogen pipeline (10) to the water inlet of the water-leaking cooling wall (1). The valve follow-up control module is used to adjust the opening degree of the clean gas valve (9) on the clean gas pipeline (8) and the nitrogen valve (11) on the nitrogen pipeline (10) in stages according to the real-time monitoring of the change in the furnace air volume during the process of the blast furnace switching to the re-air state. The target flow calculation module is used to calculate the net gas target flow of a single water-leaking cooling wall (1) when the furnace air volume reaches the value of the furnace air volume during normal production, and adjust the corresponding net gas flow and the final nitrogen target flow according to the net gas target flow. The temperature monitoring and adaptive adjustment module includes a gas temperature sensor (12) installed on the clean gas pipeline (8) and a cooling wall temperature sensor (13) installed on the water-leaking cooling wall (1) near the inner surface of the furnace skin. It is used to adaptively adjust the opening of the clean gas valve (9) and the nitrogen valve (11) based on the temperature feedback value, and to trigger the fabrication system to perform intervention operation or start extreme protection operation when the temperature exceeds the safety limit.

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