Control system and method for uniform pulverized coal injection and local reinforcement of blast furnace

Abstract

The invention belongs to the field of blast furnace ironmaking control, and discloses a control system and method for uniform pulverized coal injection and local reinforcement of a blast furnace, which can effectively eliminate uneven coal injection quantity between tuyeres caused by pipeline layout, length and resistance difference through real-time flow monitoring and intelligent adjustment of each coal injection branch pipe, and improve the coal injection efficiency. Uniformity of multi-tuyere pulverized coal injection is achieved, and reaction conditions in the furnace are optimized. According to the method, the coal injection quantity of individual coal injection branch pipes is accurately adjusted aiming at the local position of the blast furnace where the smelting reaction needs to be enhanced, the regional reaction efficiency is improved, and the overall smelting strength and production efficiency of the blast furnace are improved. The master control system is adopted for centralized management, the opening degree of each flow regulating valve is automatically regulated by the master control system, frequent manual intervention is not needed, the regulating precision is high, the response speed is high, and the automation level of the injection system is greatly improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of blast furnace ironmaking control, and particularly relates to a control system and method for uniform coal powder injection and local strengthening of a blast furnace. BACKGROUND

[0002] Coal powder injection of a blast furnace is an important means to reduce coke ratio. At present, the blast furnace coal injection process is mainly realized by a pulverizing system, a coal powder storage system, a conveying system and an injection system through the following steps: Raw coal is crushed and dried and then enters a coal mill to be ground into coal powder. The prepared coal powder is conveyed to an injection tank by using nitrogen or compressed air as a conveying medium. The coal powder is stored and homogenized in the injection tank for a short time to ensure uniformity and stability of the coal powder in the injection process. The coal powder enters the coal powder distributor from the injection tank through a pipeline, and is then conveyed to each coal injection branch pipe by the coal powder distributor. The coal powder is injected into the blast furnace through the tuyere coal injection gun by pneumatic transmission. The coal powder is injected into the blast furnace through the coal injection gun, mixed with high-temperature blast in the raceway, and subjected to a combustion reaction. During the conveying process, the injection pressure and flow rate are strictly controlled to ensure that the coal powder is stably and continuously injected into the blast furnace, so as to achieve the best combustion effect and improve the production efficiency and economy of the blast furnace.

[0003] However, the coal powder injection into the blast furnace is a gas-solid two-phase flow transmission process. The physical position of the injection system distributor of the actual blast furnace coal injection system and the blast furnace determines that the length, bending form and degree of each coal injection branch pipe are different, which causes inconsistent damping characteristics of each branch pipe, and further causes uneven distribution of flow rate, concentration and fineness of each coal injection branch pipe. When a branch pipe injects more coal powder, the coal powder burnout rate will decrease, and excessive unburned coal powder will reduce the permeability of the blast furnace column, and in severe cases, will cause the furnace hearth to be stacked or the material to be suspended. If insufficient coal powder is injected, the excessive reaction of hot blast and coke will be caused, the coke ratio will be increased, and various economic and technical indicators will be decreased. At the same time, the existence of unburned coal powder is detected in the blast furnace dust, which shows that there is a great space for improvement in the technical parameters and control means of the coal injection process.

[0004] Therefore, it is necessary to improve the uniformity of each tuyere coal injection to solve the problems of low coal powder burnout rate and uneven smelting conditions around the blast furnace. SUMMARY

[0005] The purpose of the present application is to overcome the problem of inconsistent coal injection amount of each tuyere caused by the design of the coal injection branch pipe, and to provide a control system and method for uniform coal powder injection and local strengthening of a blast furnace.

[0006] In order to achieve the above purpose, the present application adopts the following technical scheme: In a first aspect, the present application provides a blast furnace uniform coal injection and local strengthening control system, comprising a coal powder distributor, the coal powder distributor comprising a coal injection main pipe and a plurality of downward coal injection branch pipes, each of the coal injection branch pipes being provided with a measurement and control integrated valve, the measurement and control integrated valve adopting a ZG40Cr25Ni20 heat-resistant cast steel valve body, the valve core being in a horn mouth type, the valve body being in a multi-stage annular non-contact labyrinth seal structure, the measurement and control integrated valve being provided with a flow monitoring sensor and a concentration monitoring sensor on the valve body of a ceramic metal composite valve, the valve core of the ceramic metal composite valve being provided with a flow regulating valve opening control unit, and the flow monitoring sensor, the concentration monitoring sensor and the flow regulating valve opening control unit being connected to a main control system. The main control system is used for setting initial openings of all flow regulating valve opening control units to be maximum, continuously collecting coal powder mass flow of each coal injection branch pipe, constructing a valve body control function according to deviations of average values and minimum values of coal injection parameters in each coal injection branch pipe, and adjusting the flow regulating valve opening control units of the coal injection branch pipes according to the valve body control function.

[0007] The present application further improves that the flow speed regulating range of the flow regulating valve opening control unit is 80-100%, and the concentration regulating range is 5-25%.

[0008] The present application further improves that the lining of the ceramic metal composite valve of the measurement and control integrated valve is SiC material.

[0009] The present application further improves that the ceramic metal composite valve of the measurement and control integrated valve adopts a passive mass induction type or a non-contact instrument.

[0010] The present application further improves that data output by the flow monitoring sensor, the concentration monitoring sensor and the flow regulating valve opening control unit are processed by a DSP digital signal processing technology of the main control system.

[0011] In a second aspect, the present application provides a blast furnace uniform coal injection and local strengthening control method, comprising the following steps: In a first step, initial openings of all flow regulating valve opening control units are set to be maximum in an initial state. In a second step, coal powder mass flow of each coal injection branch pipe is continuously collected. In a third step, a valve body control function is constructed according to deviations of average values and minimum values of coal injection parameters in each coal injection branch pipe, the openings of the flow regulating valves on all coal injection branch pipes in the initial state are set to be maximum through the valve body control function, and a control parameter system with maximum overall opening of the valve body is adopted to reduce damping in a coal injection pipeline system. Fourth step: in the first adjustment period, the coal injection parameter of each coal injection branch pipe is brought into the valve control function, the corresponding valve opening value of each branch pipe is calculated, and the valve dynamic opening parameter set of all coal injection branch pipes is formed; Fifth step: in the second adjustment period, the opening control of the flow regulating valve of the coal injection branch pipe is completed according to the specific data of the valve dynamic opening parameter set of the coal injection branch pipe, and the coal injection parameters of each coal injection branch pipe after the adjustment of the valve opening are continuously collected.

[0012] Sixth step: the coal injection parameters of each coal injection branch pipe after the adjustment are used to repeat the operation of the fourth step and the fifth step until the pulverized coal mass flow of each coal injection branch pipe approaches the average target value.

[0013] Further improvement of the present application is that, in a certain specific time period, when the local strengthening control of the coal injection of a target coal injection branch pipe is needed, the coal injection parameter strengthening target value of the target coal injection branch pipe is used to replace the average value, the coal injection parameters of the remaining coal injection branch pipes are averaged again, the valve dynamic opening parameter set is calculated through the requirement of the coal injection parameter strengthening target value of the specific branch pipe and the average value of the coal injection parameters of the remaining branch pipes, and the opening control of the mass flow regulating valve is completed in the specific time period, so that the local strengthening of the coal injection of the target coal injection branch pipe is completed under the premise of ensuring the uniformity of the coal injection parameters of the remaining coal injection branch pipes, and after the strengthening period is over, the operation of the fourth step, the fifth step and the sixth step is repeated in the next adjustment period, so that the dynamic uniform adjustment mechanism of the blast furnace coal injection is restored.

[0014] Further improvement of the present application is that the valve control function is:

[0015] Wherein, wherein, is the opening value of the valve of the i th coal injection branch pipe, is the minimum value of the coal injection parameters in all coal injection branch pipes, is the average value of the coal injection parameters, is the coal injection parameter of the i th coal injection branch pipe; is the valve control parameter determined by the deviation of the minimum value and the average value of the coal injection parameters of the coal injection branch pipe; is the valve control parameter determined by the deviation of the coal injection parameter of the i th coal injection branch pipe and the minimum value; is the valve opening control function.

[0016] Further improvement of the present application is that, The expression of is:

[0017] Wherein, A is the valve body adjustment overall control coefficient, when , .

[0018] The further improvement of the present application is that, The expression is:

[0019] Wherein, B is the valve body adjustment individual control coefficient, when , .

[0020] The further improvement of the present application is that the valve body opening control function is:

[0021] Wherein, is the opening adjustment step of the valve body in a regulation period, is the valve body regulation period, when , .

[0022] Compared with the prior art, the present application has the following beneficial effects: The present application can effectively eliminate the unevenness of the coal injection amount among the tuyeres caused by the differences in pipeline layout, length and resistance, realize the uniformity of the multi-tuyere pulverized coal injection, and optimize the reaction conditions in the furnace. The present application can precisely adjust the coal injection amount of individual coal injection branch pipes according to the local position of the blast furnace that needs to be strengthened for smelting reaction, and improve the regional reaction efficiency, which is helpful to improve the overall smelting intensity and production efficiency of the blast furnace. The present application adopts centralized management of the main control system, and the opening of each flow regulating valve is automatically adjusted by the main control system without frequent manual intervention, so that the adjustment precision is high, the response speed is fast, and the automation level of the injection system is greatly improved. The real-time monitoring of the concentration and flow combined with the linkage adjustment of the valve can timely find and adjust the abnormal coal injection caused by local enrichment or blockage, avoid operation accidents such as tuyere coking and blockage, and improve the safety and stability of equipment operation. The present application realizes dynamic balanced distribution of the coal injection flow, avoids the increase of energy consumption and equipment wear caused by local excessive injection, helps to reduce the overall energy consumption, and prolongs the service life of the valve and the pipeline system. The control system of the present application can adapt to the injection requirements under different production stages and different raw material conditions, flexibly adjust the coal injection strategy, and has good adaptability and expansibility, which is convenient for subsequent upgrading and modification. The present application realizes the reduction of the coal injection parameters of the target coal injection branch pipe by reducing the opening of the flow regulating valve of the target coal injection branch pipe and increasing the opening of the flow regulating valve of other coal injection branch pipes except the target coal injection branch pipe, and realizes the increase of the coal injection parameters of the target coal injection branch pipe by increasing the opening of the flow regulating valve of the target coal injection branch pipe and reducing the opening of the flow regulating valve of other coal injection branch pipes except the target coal injection branch pipe.

[0023] In summary, the present application adopts uniform coal injection and local strengthening to make the heat and reducing agent distribution in the blast furnace more reasonable, promote the complete reaction of the furnace charge, improve the smelting yield and quality, reduce the consumption of raw materials and fuels, and improve the economic benefits. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a schematic diagram of the coal powder distributor and the conveying pipeline structure in the present application; Figure 2 is a schematic diagram of the installation position of the monitoring element and the flow regulating valve opening control element on each coal injection branch pipe in the present application; Figure 3 is a schematic diagram of the uniform coal injection control system in the present application; Figure 4 is a flowchart of the present application; wherein 1 is a coal injection main pipe; 2 is a coal injection branch pipe; 3 is a flow monitoring sensor; 4 is a concentration monitoring sensor; 5 is a flow regulating valve opening control unit; 6 is a data line; 7 is a power line; 8 is a main control system; and 9 is a coal powder distributor. DETAILED DESCRIPTION

[0025] In order to further understand the content of the present application, the present application is described in detail below in combination with the drawings and specific embodiments. It should be understood that the embodiments are merely used to explain and not to limit the present application.

[0026] Referring to Figure 1 , Figure 2 and Figure 3 , a control system for uniform coal powder injection and local strengthening of a blast furnace includes a coal powder distributor 9, the coal powder distributor 9 includes a coal injection main pipe 1, the coal injection main pipe 1 is connected to a plurality of downwardly extending coal injection branch pipes 2, the coal injection branch pipes 2 are provided with integrated measurement and control valves, the integrated measurement and control valves are ceramic metal composite valves, the valve core of the integrated measurement and control valves is in the shape of a bell mouth, the valve body of the integrated measurement and control valves has a multi-stage annular non-contact labyrinth seal structure, the valve body of the integrated measurement and control valves is provided with a flow monitoring sensor 3 and a concentration monitoring sensor 4, the valve core of the integrated measurement and control valves is provided with a flow regulating valve opening control unit 5, and the flow monitoring sensor 3, the concentration monitoring sensor 4 and the flow regulating valve opening control unit 5 are all connected to a main control system 8. The main control system 8 is used to set the initial opening of all the flow regulating valve opening control units 5 to the maximum, continuously collect the coal powder mass flow of each coal injection branch pipe 2, construct a valve body control function according to the deviation of the target value and the minimum value of the coal injection parameters in each coal injection branch pipe 2, and adjust the flow regulating valve opening control units 5 of the other coal injection branch pipes 2 outside the target coal injection branch pipe 2 according to the valve body control function.

[0027] Referring to Figure 4 A control method for uniform injection of pulverized coal and local strengthening in a blast furnace, comprising the following steps: Step 1: In the initial state, set the initial opening of the flow regulating valve opening control unit 5 to the maximum; Step 2: Continuously collect the mass flow of pulverized coal of each coal injection branch pipe 2; Step 3: According to the deviation of the average value and the minimum value of the coal injection parameters in each coal injection branch pipe 2, construct a valve body control function, set the opening of the flow regulating valve 5 in all coal injection branch pipes 2 to the maximum in the initial state through the valve body control function, and use the valve body overall opening maximum control parameter system to reduce the damping in the coal injection pipeline system; Step 4: In the first adjustment period, first introduce the coal injection parameters of each coal injection branch pipe 2 into the valve body control function, calculate the corresponding valve body opening value of each branch pipe 2, and form a valve body dynamic opening parameter set of all coal injection branch pipes 2; Step 5: In the second adjustment period, according to the specific data of the valve body dynamic opening parameter set of the coal injection branch pipe 2, complete the opening control of the flow regulating valve 5 of the coal injection branch pipe 2, and continuously collect the coal injection parameters of each coal injection branch pipe after adjusting the valve opening.

[0028] Step 6: Using the adjusted coal injection parameters of each coal injection branch pipe 2, repeat the operations of steps 4 and 5 until the mass flow of pulverized coal of each coal injection branch pipe is close to the average target value.

[0029] In a certain time period, when local strengthening control of coal injection of a target coal injection branch pipe 2 is needed, the coal injection parameter strengthening target value of the target coal injection branch pipe 2 is used instead of the average value, and the coal injection parameters of the remaining coal injection branch pipes 2 are averaged again. According to the requirements of the specific branch pipe opening coal injection parameter strengthening target value and the remaining branch pipe opening coal injection parameter average value, calculate the valve body dynamic opening parameter set, and complete the opening control of the mass flow regulating valve 5 in the specific time period. On the premise of ensuring the uniformity of the coal injection parameters of the remaining coal injection branch pipes, the local strengthening of the target coal injection branch pipe 2 is completed. After the strengthening period is over, repeat the operations of steps 4, 5 and 6 in the next adjustment period to restore the dynamic uniform adjustment mechanism of the blast furnace coal injection.

[0030] Example 1: In order to minimize the resistance loss in the process of coal powder transportation, the initial opening of all valve bodies should be set at 100%. In order to make the mass flow of coal in all spray guns uniform, in the case of considering the linkage change of the mass flow of coal in all spray guns, the valve opening of the remaining spray guns should be properly reduced to increase the mass flow of coal in the spray gun with the minimum coal injection amount (at this time, the valve opening of the spray gun is 100% and cannot be increased any more), and the mass flow of coal in other spray guns should be reduced to achieve the purpose of increasing the mass flow of coal in the spray gun with the minimum coal injection amount. When the mass flow of coal in a spray gun needs to be reduced, the valve opening of the spray gun should be directly reduced. That is, the spray gun with the minimum mass flow of coal is taken as the reference, and the valve openings of the remaining spray guns should be reduced to achieve uniform mass flow of coal. In addition, since the deviation of the mass flow of coal in each spray gun from the average value and the minimum value is different, in order to realize the rapid adjustment of the mass flow of coal in all spray guns, the valve control function should be constructed according to the deviation of the mass flow of coal in each spray gun from the target value and the minimum value, and the rapid response of the valve body should be realized.

[0031] Construction of valve opening control function

[0032]

[0033] wherein, is the opening value of the valve body of the i-th spray gun (80% to 100%), is the minimum value of the coal injection parameter in all spray guns, is the average value of the coal injection parameter, is the coal injection parameter of the i-th spray gun; is the valve control parameter determined by the deviation of the minimum value of the coal injection parameter in the spray gun from the average value, which determines the overall opening and closing adjustment of all valve bodies and the response rate of the valve body, and the expression is: ; A is the overall control coefficient of the valve adjustment, when , ; is the valve control parameter determined by the deviation of the coal injection parameter of the i-th spray gun from the minimum value, which determines the opening and closing adjustment of the valve body of the i-th spray gun, and the expression is: ; B is the individual control coefficient of the valve adjustment, when , ; is the valve opening control function, which determines the valve opening when a certain damping value is added to the i-th branch to achieve the uniformity of the coal injection parameters. The value range is 80%~100%, and the expression is:

[0034] wherein is the valve opening adjustment in a regulation period, and the step size is is the valve regulation period, and when , that is, when the uniformity of the coal injection parameters of each branch is achieved, the specific opening of each branch and the valve is determined by the function .

[0035] Example 2: The integrated measurement and control valve installed on the pulverized coal branch adopts a ceramic metal composite valve core, and the valve core flow passage is in the shape of a trumpet mouth, effectively preventing the erosion and wear of the valve body by coal particles. The multi-stage annular non-contact labyrinth seal structure is used around the valve stem, effectively preventing the coal powder from entering and causing jamming or wear. The integrated measurement and control valve installed on the pulverized coal branch uses advanced passive mass induction type, non-contact instrument, and based on the measurement equipment of alternating current charge induction technology, realizes the measurement of the gas-solid two-phase flow velocity and concentration of the transported coal powder. The data processing unit of the integrated measurement and control valve installed on the pulverized coal branch uses DSP digital signal processing technology to complete signal acquisition, analysis, and calculation. The digital field bus output controls the parameters of the related automatic flow regulating valve. The flow regulating valve and opening control unit 5 have the functions of gas-solid two-phase flow velocity and concentration adjustment, can dynamically adjust the opening of the regulating valve 5 according to the size of the mass flow difference, and according to the change of the flow after adjusting the regulating valve feedback by the parameter real-time monitoring unit 3-4, repeatedly correct the valve opening to achieve the purpose of equalizing the flow of each outlet. Its flow velocity regulation range is 80-100%, and the concentration regulation range is 5~25%. Its power supply adopts low-voltage bus power supply mode. The control mode adopts field bus control. The control valve body lining is made of SiC material structure.

[0036] The real-time monitoring unit composed of the coal powder flow monitoring sensor 3 and the concentration monitoring sensor 4 uses an advanced passive mass inductive measurement technology, and based on the measurement equipment of the alternating current charge inductive technology, the real-time and accurate measurement of the coal powder flow rate, the coal powder concentration and the coal powder fineness in the coal injection branch pipe 2 can be realized without changing the original coal powder conveying system. The measurement accuracy is better than 0.1%, and the repeatability is 0.1%. The flow monitoring sensor 3 and the concentration monitoring sensor 4 used by the monitoring unit simultaneously have the unstable flow condition and the dynamic uniformity parameter output function of the gas-solid two-phase fluid. The structure form adopts the pipeline type measurement form, the inside of the measurement pipeline adopts the same inner lining of corundum as the inner diameter of the coal powder conveying pipe, there is no blocking element, and the inner diameter of the instrument is completely consistent with the inner diameter of the pipeline. It has a durable structure design.

[0037] The coal powder enters the coal powder distributor from the coal powder main pipe 1, and is divided into multiple coal powder flows in the coal powder distributor and is distributed to the circumferential coal injection branch pipes 2, and finally is injected into the blast furnace through the coal injection guns connected at the ends of the coal injection branch pipes 2. When the coal powder flows to the flow monitoring sensor 3 and the concentration monitoring sensor 4 installed on the coal injection branch pipe 2, the sensors will monitor the coal powder flow and concentration data in each branch pipe in real time, and transmit them back to the main control system 8 through the data line 6. The data processing unit in the main control system 8 will calculate the difference between the coal powder flow of each branch pipe and the average flow, and under the condition of keeping the minimum coal injection amount branch pipe regulating valve opening degree 100%, drive and automatically adjust the opening degree of the flow regulating valve on the remaining branch pipes through the power line 7, so as to ensure the uniformity of the coal powder mass flow of each branch pipe. In the whole adjustment process, the main control system 8 will continuously collect real-time coal powder flow data through the data line 6, and dynamically adjust the opening degree of the regulating valve 5 according to the change of the flow, until the coal powder mass flow of each coal injection branch pipe 2 reaches uniformity.

[0038] The present application realizes the uniformity of the coal powder injection at each tuyere of the blast furnace by real-time monitoring the coal powder mass flow in each branch pipe and controlling the opening degree of the regulating valve according to the difference between the mass flow of each branch pipe and the average mass flow. The present application uses a passive mass inductive non-contact measurement instrument to realize the accurate measurement of the coal powder mass flow in each branch pipe, and provides data support for realizing the automatic adjustment of the flow size of the valve body. The present application can real-time monitor the coal powder mass flow in each branch pipe, and dynamically adjust and control the opening degree of the valve according to the actual production furnace condition, so as to keep the best combustion state of the furnace condition. The present application accurately controls the coal injection amount of each coal injection gun under the condition of ensuring the uniformity of the coal injection, effectively improves the coal powder burnout rate, makes the smelting environment in the furnace more uniform and stable in the circumferential direction, and promotes the stable production of the blast furnace, the smooth operation of the furnace condition and the fuel consumption control. The present application is installed at each branch pipe of the coal powder distributor, has a whole modularization, is convenient to install, and improves the automatic control level of the coal powder injection process of the blast furnace. At the same time, the coal injection measurement and control system generates a large amount of derivative data, which provides data support for the big data analysis and application in the production process of the blast furnace.

[0039] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application but not to limit it. Although the present application has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the specific embodiments of the present application can be modified or equivalently replaced without departing from the spirit and scope of the present application, and any modification or equivalent replacement should be covered within the protection scope of the claims of the present application.

Claims

1. A control system for uniform pulverized coal injection and localized strengthening in a blast furnace, characterized in that, The system includes a coal powder distributor (9), which consists of a coal injection main pipe (1) and several downward-hanging coal injection branch pipes (2). Each coal injection branch pipe (2) is equipped with a measurement and control integrated valve. The measurement and control integrated valve adopts a ZG40Cr25Ni20 heat-resistant cast steel valve body, the valve core is in the shape of a flared mouth, and the valve body has a multi-stage annular non-contact labyrinth seal structure. The valve body of the ceramic-metal composite valve is equipped with a flow monitoring sensor (3) and a concentration monitoring sensor (4). The valve core of the ceramic-metal composite valve is equipped with a flow regulating valve opening control unit (5). The flow monitoring sensor (3), the concentration monitoring sensor (4) and the flow regulating valve opening control unit (5) are all connected to the main control system (8). The main control system (8) is used to set the initial opening of all flow regulating valve opening control units (5) to the maximum, continuously collect the coal powder mass flow rate of each coal injection branch (2), construct the valve body control function based on the deviation of the average value and minimum value of the coal injection parameters in each coal injection branch (2), and then adjust the flow regulating valve opening control units (5) of each coal injection branch (2) in conjunction with the valve body control function.

2. The control system for uniform pulverized coal injection and localized strengthening in a blast furnace according to claim 1, characterized in that, The flow rate regulation range of the flow regulating valve opening control unit (5) is 80-100%, and the concentration regulation range is 5-25%.

3. The control system for uniform pulverized coal injection and localized strengthening in a blast furnace according to claim 1, characterized in that, The integrated measurement and control valve uses a ceramic-metal composite valve with SiC material as the inner lining.

4. The control system for uniform pulverized coal injection and localized strengthening in a blast furnace according to claim 1, characterized in that, The integrated measurement and control valve uses passive mass sensing or non-contact instruments.

5. A method for controlling uniform pulverized coal injection and localized strengthening in a blast furnace, based on the control system for uniform pulverized coal injection and localized strengthening in a blast furnace as described in claim 1, characterized in that... Includes the following steps: Step 1: In the initial state, set the initial opening of all flow control valve opening control units (5) to the maximum; Step 2: Continuously collect the pulverized coal mass flow rate of each pulverized coal injection branch (2); Step 3: Based on the deviation of the average and minimum values ​​of the coal injection parameters in each coal injection branch pipe (2), construct the valve body control function. Through the valve body control function, set the opening of the flow regulating valve (5) on all coal injection branch pipes (2) to the maximum in the initial state. Use the control parameter system with the maximum overall valve body opening to reduce the damping in the coal injection pipeline system. Step 4: In the first adjustment cycle, first input the coal injection parameters of each coal injection branch (2) into the valve body control function, calculate the valve body opening value corresponding to each branch (2), and form a set of valve body dynamic opening parameters for all coal injection branch (2); Step 5: During the second adjustment cycle, based on the specific data of the valve body dynamic opening parameter set of the pulverized coal branch pipe (2), complete the opening control of the flow regulating valve (5) of the pulverized coal branch pipe (2), and continuously collect the pulverized coal parameters of each pulverized coal branch pipe after adjusting the valve body opening. Step 6: Using the adjusted pulverized coal injection parameters of each pulverized coal branch pipe (2), repeat the operations of Step 4 and Step 5 until the pulverized coal mass flow rate of each pulverized coal branch pipe is close to the average target value.

6. The method for controlling uniform pulverized coal injection and localized strengthening in a blast furnace according to claim 5, characterized in that, Within a specific time period, when it is necessary to perform local enhanced control of pulverized coal injection in a target pulverized coal injection branch (2), the enhanced target value of the pulverized coal injection parameters of the target pulverized coal injection branch (2) is used to replace the average value, and the average value of the pulverized coal injection parameters of the remaining pulverized coal injection branch (2) is recalculated. Based on the requirements of the enhanced target value of the pulverized coal injection parameters of the specific branch and the average value of the pulverized coal injection parameters of the remaining branch, the dynamic opening parameter set of the valve body is calculated, and the opening control of the mass flow regulating valve (5) is completed within the specific time period. Under the premise of ensuring the uniformity of the pulverized coal injection parameters of the remaining pulverized coal injection branch, the local enhanced pulverized coal injection in the target pulverized coal injection branch (2) is completed. After the enhanced cycle ends, the fourth, fifth and sixth steps are repeated in the next adjustment cycle to restore the dynamic uniform adjustment mechanism of pulverized coal injection in the blast furnace.

7. The method for controlling uniform pulverized coal injection and localized strengthening in a blast furnace according to claim 5, characterized in that, The valve body control function is: Among them, Let i be the opening value of the i-th pulverized coal injection branch valve body. The minimum value of the pulverized coal injection parameters among all pulverized coal injection branch pipes. Average values ​​of pulverized coal injection parameters Let be the pulverized coal injection parameters for the i-th pulverized coal injection branch pipe; The valve body control parameters are determined by the deviation between the minimum and average values ​​of the pulverized coal injection parameters in the pulverized coal injection branch pipe. The valve body control parameters are determined by the deviation between the pulverized coal injection parameters of the i-th pulverized coal injection branch and the minimum value. This is the valve body opening control function.

8. The method for controlling uniform pulverized coal injection and localized strengthening in a blast furnace according to claim 7, characterized in that, The expression is: Where A is the overall control coefficient for valve body adjustment, when hour, .

9. The method for controlling uniform pulverized coal injection and localized strengthening in a blast furnace according to claim 8, characterized in that, The expression is: Where B is the individual control coefficient for valve body adjustment, when hour, .

10. The method for controlling uniform pulverized coal injection and localized strengthening in a blast furnace according to claim 8, characterized in that, Valve body opening control function for: in, This refers to the valve body's opening adjustment step size within one adjustment cycle. For valve body adjustment cycle, when hour, .

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