Processing method and system capable of effectively controlling top pressure furnace condition fluctuation of blast furnace

Abstract

The invention relates to the technical field of smelting, and discloses a treatment method and system capable of effectively controlling top pressure furnace condition fluctuation of a blast furnace, which can effectively solve the problem of furnace condition fluctuation expansion in the furnace condition recovery process in the prior art, and comprises the following steps: S1, detecting the furnace condition of the blast furnace, if the conditions of poor stock rod action, poor air permeability after material collapse and slipping, large air pressure and air volume relation fluctuation and the like occur, blast furnace air reduction operation is carried out, and the blast furnace pressure difference # imgabs0 # after air reduction is maintained to be lower than the blast furnace pressure difference # imgabs1 # before air reduction; s2, the furnace top pressure of the blast furnace is reduced while wind reduction is not conducted, and the furnace top pressure is reduced in equal amplitude; s3, the pressure difference of the blast furnace after the furnace top pressure is reduced is detected, and when the pressure difference is reduced to be not higher than the level before reduction, the furnace top pressure continues to be reduced at equal amplitude; and S4, when the stock rod moves back to normal, the wind pressure and the furnace top pressure are gradually recovered to normal working parameters. By means of the technical scheme, the furnace condition fluctuation duration time can be remarkably shortened, and insufficient blast kinetic energy and furnace condition deterioration caused by pure air reduction operation are avoided.

Description

Technical Field

[0001] The present invention relates to the field of smelting technology, and in particular to a processing method and system for effectively controlling fluctuations in blast furnace top pressure and furnace conditions. Background Art

[0002] In order to reduce costs, blast furnaces continue to increase the proportion of economic material consumption, "walking a tightrope" to reduce costs, and face the risk of unfavorable furnace conditions. In addition, when blast furnaces are undergoing long-term planned maintenance or unplanned shutdowns, the furnace condition is prone to unfavorable conditions during the recovery process. Improper handling will lead to amplified fluctuations in furnace conditions, frequent material collapses, inability to eliminate pipeline airflow, furnace cooling, etc., resulting in heavy losses. It is of great significance to study the rapid handling of furnace condition fluctuations under low-cost production models.

[0003] The following technical solutions are generally used to deal with abnormal blast furnace conditions: by keeping the furnace top pressure unchanged, reducing the blast furnace air pressure, and improving the charge drop by reducing the pressure difference; however, as the wind pressure decreases, the blast furnace air volume also decreases. If it can be restored in the short term, it will not have a major impact on the furnace condition. However, if it cannot be restored in the short term, the blast kinetic energy will be low for a long time, and problems will occur in the initial airflow distribution of the furnace cylinder, which will aggravate the fluctuation of the furnace condition. Summary of the Invention

[0004] In view of the above-mentioned shortcomings of the prior art, the present invention provides a processing method and system for effectively controlling the fluctuation of blast furnace top pressure and furnace condition, which can effectively solve the problem of the expansion of furnace condition fluctuation during the furnace condition recovery process in the prior art.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: The present invention provides a method for effectively controlling fluctuations in blast furnace top pressure and furnace conditions, which is characterized by comprising the following steps: S1. Check the blast furnace condition. If the probe action is poor or the air permeability is poor after the collapse and sliding of materials, or the relationship between the wind pressure and air volume fluctuates greatly, the blast furnace air reduction operation should be carried out at this time, and the pressure difference of the blast furnace after the air reduction should be maintained. Lower than the blast furnace pressure difference before wind reduction ; S2. The blast furnace top pressure is reduced without reducing the air flow, and the top pressure is reduced by the same amount; S3. Detect the pressure difference of the blast furnace after reducing the furnace top pressure. When the pressure difference drops to no higher than the level before the reduction, continue to reduce the furnace top pressure by a constant amount. S4. After the probe action returns to normal, the wind pressure and air volume relationship is stable, and the gas utilization rate is stable, gradually restore the wind pressure and furnace top pressure to normal working parameters.

[0006] Furthermore, in the process of reducing the furnace top pressure in step S2 and step S3, the air flow reduction and wind pressure reduction operations are not performed to maintain the stability of the blast kinetic energy and the initial flow distribution of the coal gas.

[0007] Furthermore, the maximum reduction in the furnace top pressure is 5% of the initial furnace top pressure.

[0008] Furthermore, in step S2, the furnace top pressure is reduced by 1 to 3 kPa.

[0009] Furthermore, in step S4, the air volume and blast kinetic energy during the process of reducing the furnace top pressure are monitored to assist in judging whether the blast furnace condition has improved. If the air volume and blast kinetic energy increase, the wind pressure and furnace top pressure values are gradually restored to normal levels after the probe action returns to normal.

[0010] A processing system capable of effectively controlling fluctuations in blast furnace top pressure and furnace conditions, characterized by comprising: The furnace condition monitoring module is used to monitor the blast furnace operating parameters in real time, including probe movement, air pressure, air volume, furnace top pressure, blast furnace pressure difference and gas utilization rate; The data analysis module is used to receive the monitoring results of the furnace condition detection module and determine whether the blast furnace condition is abnormal; The blast furnace air reduction module is connected to the data analysis module signal, and is used to control the blast furnace blast system to reduce the air flow when the data analysis module determines that the blast furnace condition is abnormal and maintain the blast furnace pressure difference after the air reduction lower than the blast furnace pressure difference before the air reduction; The furnace top pressure reduction module is connected to the furnace condition monitoring module signal, and is used to stop the blast furnace air reduction operation and control the furnace top pressure to reduce by an equal amplitude when the blast furnace pressure difference after blast reduction is lower than the blast furnace pressure difference before blast reduction; Feedback judgment module, used to monitor and compare the change of blast furnace pressure difference after each adjustment of furnace top pressure, and feed back the change result to the furnace top pressure reduction module; When the blast furnace pressure difference after adjusting the furnace top pressure is not higher than the blast furnace pressure difference before adjusting the furnace top pressure, the feedback judgment module outputs a control signal to the furnace top pressure reducing module to control the furnace top pressure to continue to decrease by a constant amplitude; And the recovery control module is used to receive the blast furnace operating parameters from the furnace condition monitoring module. When the probe action returns to normal, the wind pressure and furnace top pressure are controlled to return to the preset values.

[0011] Furthermore, a permeability calculation module is included, which is used to calculate the blast furnace permeability index according to the following formula and feed it back to the furnace condition monitoring module: , where K is the air permeability index, Q is the air volume, is the pressure difference.

[0012] Furthermore, it also includes a blast kinetic energy calculation module, which is used to calculate the blast kinetic energy of the blast furnace according to the following formula and feed it back to the furnace condition monitoring module: , where E is the kinetic energy of the blast, ρ is the blast density, n is the number of tuyere, d is the tuyere diameter, and T is the wind temperature.

[0013] Furthermore, when the feedback judgment module determines that the blast furnace pressure difference after adjusting the furnace top pressure is greater than the blast furnace pressure difference before adjusting the furnace top pressure, the feedback judgment module outputs a control signal value to the furnace top pressure reducing module, which is used to stop the furnace top pressure reducing module from continuing to reduce the furnace top pressure.

[0014] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects: 1. By reducing the furnace top pressure, the downward compaction effect on the soft melting zone column is reduced, the porosity of the soft melting zone and the column is increased, and the permeability is significantly improved. When the furnace condition is not favorable, it can effectively guide the gas flow, quickly eliminate the adverse phenomena such as pipeline airflow and suspended materials, and restore normal gas distribution; 2. While the furnace top pressure is reduced, the air flow reduction operation is not performed, ensuring that the blast kinetic energy will not be too low for a long time. Even under low air pressure and low pressure difference conditions, the blast furnace air volume can slightly increase due to the reduced resistance, and the initial gas flow distribution in the tuyere area remains basically normal. Therefore, the deterioration of the hearth caused by long-term low air pressure operation in the traditional method can be avoided, preventing the furnace condition from falling into a vicious cycle. 3. The strategy of reducing the furnace top pressure in small increments multiple times is adopted to make the operation process smooth and gradual, without causing new impact on the furnace condition. It is safe and reliable. This method can be implemented using existing blast furnace top relief valves and other equipment without adding new hardware facilities. It can be achieved only by improving the operation and control strategy, which has strong practicality and promotion value. 4. The technical solution provided by the present invention can be used to restore the furnace condition after a long period of blast furnace shutdown or to control the furnace condition under low-grade charge conditions, greatly shortening the duration of abnormalities, reducing the loss of pig iron production and quality caused by furnace condition fluctuations, and providing a strong guarantee for the stable and smooth operation of the blast furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0016] Figure 1 This is a flow chart of a method for effectively controlling fluctuations in blast furnace top pressure and furnace conditions according to the present invention; Figure 2 The present invention is a schematic structural diagram of a processing system that can effectively control fluctuations in blast furnace top pressure and furnace conditions. DETAILED DESCRIPTION

[0017] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0018] The present invention will be further described below with reference to the embodiments.

[0019] First, the soft melting zone is used as the stress point to analyze the effect of furnace top pressure on the permeability of the soft melting zone: From the force analysis of the soft melting zone, we can know that the downward force on the soft melting zone of the blast furnace is: F1=W 料 +P 顶 -P 墙 ; Among them, W 料 is the gravity of the charge above the soft melting zone; P 顶 is the furnace top pressure; P 墙 The friction force generated by the furnace wall on the charge; Upward force below the soft melting zone: F2=P 风 +P 浮 ; Among them, P 风 P is the pressure exerted by the gas on the soft melting zone from below; 浮 is the pressure exerted on the soft melting zone by the coke grid under the dripping zone; from the above analysis, it can be seen that the soft melting zone is subjected to downward force F1 and upward force F2, so the permeability of the soft melting zone is affected not only by the thickness of the coke layer itself and the soft melting performance of the ore, but also by F1 and F2. The soft melting zone is compressed by F1 and F2, especially when the softened material is compressed, the porosity of the soft melting zone will decrease, thereby making the permeability of the charge worse, especially for blast furnaces with re-air or abnormal furnace conditions, the initial slag has poor fluidity, and the porosity of the soft melting zone after compression decreases even more.

[0020] Based on the above analysis, the present invention provides a method for effectively controlling the fluctuation of blast furnace top pressure, comprising the following steps: S1. Check the blast furnace condition. If the probe action is poor or the air permeability is poor after the collapse and sliding of materials, or the relationship between the wind pressure and air volume fluctuates greatly, the blast furnace air reduction operation should be carried out at this time, and the pressure difference of the blast furnace after the air reduction should be maintained. Lower than the blast furnace pressure difference before collapse and slippage At this time, the blast furnace air volume decreases and the blast kinetic energy E is greatly reduced.

[0021] S2. The blast furnace top pressure is reduced without reducing the air flow, and the top pressure is reduced by the same amount; The reduction range of furnace top pressure is limited to 1-3 kPa. In this embodiment, the specific single reduction range is 2 kPa, and the maximum reduction range of furnace top pressure is 5% of the initial furnace top pressure to avoid a large reduction in furnace top pressure causing an instantaneous pressure difference (P 风 -P 顶 ) is too large, thereby aggravating the furnace condition.

[0022] S3. Detect the pressure difference of the blast furnace after reducing the furnace top pressure. When the pressure difference drops to no higher than the level before the reduction, continue to reduce the furnace top pressure by a constant amount. According to the force analysis of the soft melting zone, the permeability of the material column is improved after the furnace top pressure is reduced. At this time, the pressure difference ≤Reduce the pressure difference before the furnace top pressure , continue to reduce the furnace top pressure, that is, if it is confirmed that the blast furnace pressure difference is no longer high after the pressure reduction (that is, not higher than the level before the pressure reduction), then the furnace top pressure reduction of the same magnitude can be carried out next time. If it is found that the pressure reduction does not bring about a decrease in the pressure difference or even an increase in the pressure difference, further pressure reduction should be temporarily suspended. In addition, during the pressure reduction process in this step, no air reduction or wind pressure reduction operations will be performed.

[0023] In this way, the furnace top pressure is gradually reduced in a cycle, the gas passage in the blast furnace is gradually unblocked, and the pressure difference in the blast furnace gradually decreases. At the same time, since the air flow is not further reduced during the process of reducing the top pressure, and the air permeability of the blast furnace is improved as the furnace top pressure is reduced, the air volume and blast kinetic energy E in the furnace will increase, and the initial gas flow distribution under low pressure can be maintained basically reasonable, avoiding the deterioration of the situation caused by insufficient blast kinetic energy due to the deterioration of the air permeability of the blast furnace caused by reducing the air flow and pressure.

[0024] S4. After the probe action returns to normal, the wind pressure and air volume relationship is stable, and the gas utilization rate is stable, gradually restore the wind pressure and furnace top pressure to normal working parameters.

[0025] When the blast furnace has a fluctuation in furnace conditions (such as hanging or sliding of the charge column or gas deviation), the traditional method often continues to reduce the air flow and pressure, while the present invention adopts a different control strategy. First, when signs of an abnormal furnace condition are detected (such as a sharp increase in the blast furnace pressure difference, a significant decrease in the probe feeding speed, etc.), the blast air pressure can be appropriately reduced to initially reduce the blast furnace pressure difference to below the level before the abnormality occurred, so as to avoid further deterioration of the furnace condition; then, without further reducing the air pressure, the furnace top pressure is gradually reduced, for example, by opening the furnace top vent valve, etc. to reduce the furnace top absolute pressure in a small decreasing manner. The reduction in furnace top pressure each time is controlled within a small range to avoid sudden large changes from impacting the furnace condition. After each top pressure reduction operation, the effect is judged by monitoring the blast furnace pressure difference: usually, after the furnace top pressure is reduced, the permeability of the charge column will be improved, which is reflected in the blast furnace pressure difference being lower or remaining the same as before the pressure reduction. If After confirming that the blast furnace pressure difference is no longer high after the pressure reduction (i.e., not higher than the level before the pressure reduction), the next furnace top pressure reduction of the same magnitude can be carried out; if it is found that the pressure reduction does not lead to a decrease in the pressure difference or even an increase in the pressure difference, further pressure reduction should be temporarily suspended to prevent counterproductive effects; the furnace top pressure is gradually reduced in this cycle, so that the gas passage in the blast furnace is gradually unblocked and the blast furnace pressure difference gradually decreases; at the same time, since the wind is not further reduced during the top pressure reduction process, and the blast flow rate even slightly increases as the resistance in the furnace decreases, the gas flow field at the hearth remains basically reasonable and does not deteriorate due to insufficient blast kinetic energy. When the blast furnace probe shows that the material speed has returned to normal and indicators such as the gas utilization rate and the furnace top temperature have stabilized, further top pressure reduction is stopped, and the wind pressure and furnace top pressure can be gradually restored to normal operating levels as needed. Through the above steps, the method of the present invention can quickly restore the permeability and stable operation of the blast furnace when the furnace condition fluctuates.

[0026] The present invention also discloses a processing system that can effectively control the fluctuation of blast furnace top pressure and furnace condition, including a furnace condition monitoring module, a data analysis module, a furnace top pressure reduction module, a feedback judgment module and a recovery control module.

[0027] Specifically, the furnace condition monitoring module is used to monitor the blast furnace operating parameters in real time. The furnace condition monitoring module is connected to the AC frequency converter or DC speed regulation device signal of the probe to monitor whether the probe's lowering, supporting, and lifting actions are normal and whether they correspond to the material level; the furnace condition detection module is connected to the blast furnace's blast system and furnace top pressure regulating device signal to monitor parameters such as wind pressure, air volume, furnace top pressure, and blast furnace pressure difference.

[0028] In addition, the furnace condition monitoring module is also connected to the control unit of the blast furnace gas utilization rate prediction model to receive the real-time blast furnace gas utilization rate prediction result. Blast furnace gas utilization rate = actual gas volume utilized / total gas volume × 100%. The blast furnace gas utilization rate, wherein the actual gas volume utilized refers to the sum of the gas volume used for blast furnace blast, hot blast stove, coke oven, power generation and other production and process. The total gas volume refers to the gas volume discharged from the blast furnace chimney and subjected to dust removal, desulfurization and other treatments. In this embodiment, a method based on infrared image processing is used to establish a gas utilization rate prediction model, including The process includes collecting infrared images of the top of the blast furnace, extracting image features, establishing a dynamic change model of gas flow distribution using clustering algorithms / statistical methods / feature recognition technology and pattern recognition technology, extracting gas flow center features, calibrating the image with the material surface position, and establishing a gas utilization rate prediction model to achieve real-time prediction of gas utilization rate. Of course, gas utilization rate monitoring can also be carried out by using radar monitoring, principal component analysis (PCA), or diffusion coefficient and reaction rate-based methods. The above methods are existing technologies in this field, so they will not be described in detail in this embodiment.

[0029] The data analysis module is connected to the furnace condition monitoring module signal to analyze whether there are abnormal fluctuations in the blast furnace condition and decide on the adjustment strategy: The data analysis module receives the monitoring information of the furnace condition monitoring module and has corresponding parameter thresholds preset internally. When the corresponding parameter exceeds or the fluctuation range exceeds the threshold, a first control signal is sent to the blast furnace air reduction module.

[0030] The blast furnace air reduction module is connected to the data analysis module and the furnace condition monitoring module. When the data analysis module determines that the blast furnace condition is abnormal, it controls the blast furnace blast system to reduce the air flow and maintain the pressure difference of the blast furnace after the air reduction lower than the pressure difference of the blast furnace before the air reduction. Specifically, after the blast furnace air reduction module receives the first control signal from the data analysis module, it controls the opening of the control valve of the blast furnace's blast system to reduce the air reduction operation, and at the same time monitors the blast furnace pressure difference after the air reduction in real time through the furnace condition detection module to ensure that the blast furnace pressure difference after the air reduction is Lower than the blast furnace pressure difference before wind reduction ,like < , then output the second control signal to the furnace top pressure relief module, if ≥ , then the opening of the control valve of the control blast system continues to decrease until < .

[0031] The furnace top pressure reduction module is connected to the blast furnace air reduction module signal and is used to control the furnace top pressure to decrease by an equal amplitude when receiving the second control signal: The furnace top pressure reducing module is connected to the furnace top pressure regulating device signal of the blast furnace. In this embodiment, the furnace top pressure regulating device takes the furnace top relief valve as an example. By controlling the opening of the relief valve, the furnace top pressure is reduced in a 2kPa decreasing manner to avoid sudden and drastic changes from causing impact on the furnace condition.

[0032] The feedback judgment module is used to receive the real-time changes in the blast furnace pressure difference from the furnace condition monitoring module. Specifically, it receives the changes in the blast furnace pressure difference after each adjustment of the furnace top pressure and feeds back the changes to the furnace top pressure reduction module according to the results: Usually, after the furnace top pressure is reduced, the permeability of the material column will be improved, which is reflected in the blast furnace pressure difference being lower or the same as before the pressure reduction. If it is confirmed that the blast furnace pressure difference is no longer high after the pressure reduction (that is, not higher than the level before the pressure reduction), the next furnace top pressure reduction of the same magnitude can be carried out. At this time, the feedback judgment module outputs the third control signal and transmits it to the furnace top pressure reduction module. The furnace top pressure reduction module continues to control the relief valve to reduce the furnace top pressure with the same amplitude. If it is found that the pressure reduction does not bring about a decrease in the pressure difference or even an increase in the pressure difference, further pressure reduction should be temporarily suspended. At this time, the feedback judgment module outputs the fourth control signal. The signal is transmitted to the furnace top pressure reducing module. At this time, the furnace top pressure reducing module suspends controlling the vent valve to increase the opening and waits for the furnace condition to self-repair until the pressure difference of the blast furnace after pressure reduction is no higher than the level before pressure reduction. The furnace top pressure is gradually reduced in this cycle, so that the gas passage in the blast furnace is gradually unblocked and the pressure difference of the blast furnace is gradually reduced. It should be noted that in the process of reducing the furnace top pressure, the air flow and pressure reduction operations are no longer performed to avoid problems with the initial air flow distribution in the furnace cylinder caused by the long-term low kinetic energy of the blast due to air flow reduction and pressure reduction, thereby exacerbating the fluctuation of the furnace condition.

[0033] The recovery control module is used to receive the blast furnace operating parameters from the furnace condition detection module, and when the furnace condition parameters gradually return to normal, control the wind pressure and furnace top pressure to return to the preset values: The recovery control module monitors the changes in various parameters through the furnace condition monitoring module. If the probe action returns to normal as the blast furnace top pressure decreases, the blast furnace blast system is controlled to gradually restore the preset air pressure and the bleed valve of the furnace top pressure regulating device is controlled to gradually restore the preset opening size, so that the blast furnace returns to normal working condition and the blast furnace enters normal operation.

[0034] In addition, the system also includes a permeability calculation module and a blast kinetic energy calculation module. The permeability calculation module calculates the blast furnace permeability index according to the following formula and feeds the calculation result back to the furnace condition monitoring module: , where K is the air permeability index, Q is the air volume, is the pressure difference.

[0035] The blast kinetic energy calculation module is used to calculate the blast furnace kinetic energy according to the following formula and feed it back to the furnace condition monitoring module: , where E is the kinetic energy of the blast, ρ is the blast density, n is the number of tuyere, d is the tuyere diameter, and T is the wind temperature.

[0036] The recovery control module uses the real-time blast furnace permeability index and blast furnace kinetic energy measured by the permeability index calculation module and the blast kinetic energy calculation module to assist in determining whether to control the blast furnace air pressure and furnace top pressure recovery, ensure normal judgment, avoid problems caused by misjudgment based solely on the probe action signal, and further reduce furnace condition fluctuations.

[0037] The following is an example of two blast furnace treatment conditions: (1) No. 1 blast furnace of Nippon Steel (3000m 3 ) There was no planned wind stop for 58 hours. The heat was low in the early stage of wind resumption, and the slag and iron discharge was not smooth. There were 5 airflow reversals. In the first 4 times, the blast furnace kept the top pressure unchanged. The pressure difference was reduced by reducing the wind pressure. The blast furnace pressure difference was gradually reduced from 155kPa to 120kPa. Among them, the duct airflow occurred on the third time. The furnace top temperature, top pressure and gas utilization rate fluctuated greatly. The blast furnace reduced the wind by a large margin. However, the 4th and 5th airflow reversals still occurred. The blast furnace air volume had increased from 4076m3 before the first reversal. 3 / min reduced to 3577m 3 / min, after the fifth airflow, the blast furnace uses the method of reducing the furnace top pressure to deal with the pipeline airflow. The blast furnace top pressure is reduced by 2kPa / time, and the blast furnace top pressure is reduced from 160kPa to 148kPa. The wind pressure automatically drops to about 260kPa. Compared with before reducing the furnace top pressure, the air volume automatically increases by 100m 3 / min (see Table 1), and since then the blast furnace overturning airflow phenomenon has disappeared.

[0038] Table 1 Record of furnace condition fluctuations and airflow handling for 5 times (2) Nippon Steel No. 3 blast furnace (3000m 3 ) It was planned to stop the air flow for 18 hours. After the air flow was restored, the air pressure and air volume recovered to 85% of the normal level 1 hour and 30 minutes later. Due to the low grade of the incoming material (54.5%) and the high slag basicity (1.3-1.4), the blast furnace was difficult to discharge the slag. At 4:50, the blast furnace experienced material slippage, with a slippage of 3.1m and 6:20 of 5.1m. After this slippage, the probe action was poor, and the gas utilization rate dropped from 45% to a minimum of 37%. The air pressure rose by 40kPa and remained high. The furnace top pressure fluctuated by >5kPa along with the distribution of material, and the TRT stator blade angle even appeared in a fully closed state. At 7:37, the blast furnace began to reduce the top pressure to treat the furnace condition, 2kPa / time. The blast furnace top pressure dropped from 177kPa to 140kPa, and the air pressure automatically dropped by about 70kPa. Compared with before the reduction of the furnace top pressure, the air volume automatically increased by 300m 3 / min (see Table 2), the blast furnace probe action gradually returned to normal, the wind pressure, air volume and gas utilization rate were stable, and the blast furnace gradually recovered its parameters.

[0039] Table 2 Record of furnace condition fluctuation treatment In the above two cases, the technical solution of the present invention was utilized to regulate the furnace condition by rationally using the furnace top pressure. This can quickly clear the permeability of the material column when abnormalities such as suspended material, sliding material, and pipeline airflow occur in the blast furnace, stabilize the airflow distribution in the furnace, significantly shorten the duration of furnace condition fluctuations, avoid insufficient blast kinetic energy and deterioration of furnace conditions caused by traditional simple air reduction operations, and achieve good production results.

[0040] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for effectively controlling fluctuations in blast furnace top pressure, characterized in that: The following steps are involved: S1. Check the blast furnace condition. If the probe action is poor or the air permeability is poor after the collapse and sliding of materials, or the relationship between the wind pressure and air volume fluctuates greatly, the blast furnace air reduction operation should be carried out at this time, and the pressure difference of the blast furnace after the air reduction should be maintained. Lower than the blast furnace pressure difference before wind reduction ; S2. The blast furnace top pressure is reduced without reducing the air flow, and the top pressure is reduced by the same amount; S3. Detect the pressure difference of the blast furnace after reducing the furnace top pressure. When the pressure difference drops to no higher than the level before the reduction, continue to reduce the furnace top pressure by a constant amount. S4. After the probe action returns to normal, the wind pressure and air volume relationship is stable, and the gas utilization rate is stable, gradually restore the wind pressure and furnace top pressure to normal working parameters.

2. The method for effectively controlling blast furnace top pressure fluctuation according to claim 1, characterized in that: In the process of reducing the furnace top pressure, the air flow and the wind pressure are not reduced in step S2 and step S3, so as to maintain the stability of the kinetic energy of the blast and the initial flow distribution of the coal gas.

3. The method for effectively controlling blast furnace top pressure fluctuation according to claim 1, characterized in that: The maximum reduction in the furnace top pressure is 5% of the initial furnace top pressure.

4. The method for effectively controlling blast furnace top pressure fluctuation according to claim 3, characterized in that: In step S2, the furnace top pressure is reduced by 1 to 3 kPa.

5. The method for effectively controlling blast furnace top pressure fluctuation according to claim 1, characterized in that: In step S4, the air volume and blast kinetic energy during the process of reducing the furnace top pressure are monitored to assist in judging whether the blast furnace condition has improved. If the air volume and blast kinetic energy increase, the wind pressure and furnace top pressure values are gradually restored to normal levels after the probe action returns to normal.

6. A processing system capable of effectively controlling fluctuations in blast furnace top pressure, characterized in that: include: The furnace condition monitoring module is used to monitor the blast furnace operating parameters in real time, including probe movement, air pressure, air volume, furnace top pressure, blast furnace pressure difference and gas utilization rate; The data analysis module is used to receive the monitoring results of the furnace condition detection module and determine whether the blast furnace condition is abnormal; The blast furnace air reduction module is connected to the data analysis module signal, and is used to control the blast furnace blast system to reduce the air flow when the data analysis module determines that the blast furnace condition is abnormal and maintain the blast furnace pressure difference after the air reduction lower than the blast furnace pressure difference before the air reduction; The furnace top pressure reduction module is connected to the furnace condition monitoring module signal, and is used to stop the blast furnace air reduction operation and control the furnace top pressure to reduce by an equal amplitude when the blast furnace pressure difference after blast reduction is lower than the blast furnace pressure difference before blast reduction; Feedback judgment module, used to monitor and compare the change of blast furnace pressure difference after each adjustment of furnace top pressure, and feed back the change result to the furnace top pressure reduction module; When the blast furnace pressure difference after adjusting the furnace top pressure is not higher than the blast furnace pressure difference before adjusting the furnace top pressure, the feedback judgment module outputs a control signal to the furnace top pressure reducing module to control the furnace top pressure to continue to decrease by a constant amplitude; And the recovery control module is used to receive the blast furnace operating parameters from the furnace condition monitoring module. When the probe action returns to normal, the wind pressure and furnace top pressure are controlled to return to the preset values.

7. The processing system capable of effectively controlling fluctuations in blast furnace top pressure and furnace conditions according to claim 6, characterized in that: It also includes a permeability calculation module for calculating the blast furnace permeability index according to the following formula and feeding it back to the furnace condition monitoring module: , where K is the air permeability index, Q is the air volume, is the pressure difference.

8. The processing system capable of effectively controlling fluctuations in blast furnace top pressure and furnace conditions according to claim 6, characterized in that: It also includes a blast kinetic energy calculation module, which is used to calculate the blast kinetic energy of the blast furnace according to the following formula and feed it back to the furnace condition monitoring module: , where E is the kinetic energy of the blast, ρ is the blast density, n is the number of tuyere, d is the tuyere diameter, and T is the wind temperature.

9. The processing system capable of effectively controlling fluctuations in blast furnace top pressure and furnace conditions according to claim 6, characterized in that: When the feedback judgment module determines that the blast furnace pressure difference after adjusting the furnace top pressure is greater than the blast furnace pressure difference before adjusting the furnace top pressure, the feedback judgment module outputs a control signal value to the furnace top pressure reducing module, which is used to stop the furnace top pressure reducing module from continuing to reduce the furnace top pressure.

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