Blast furnace pipeline airflow regulation and control device and control method

Abstract

The invention relates to the technical field of airflow regulation and control, and discloses a blast furnace pipeline airflow regulation and control device and a blast furnace pipeline airflow regulation and control method. When the average pressure of the furnace top exceeds the limit, the system recognizes the airflow form according to the spatial dispersion: if the spatial dispersion is smaller than a threshold value, it is judged that the blast furnace is in a normal state, and equipment does not need to act, so that material setting impact caused by mistaken pressure relief is avoided; if the spatial dispersion is larger than or equal to the threshold value, it is judged that the working condition is the real pipeline airflow working condition, and the anti-surge valve is driven to be opened to the target opening degree for pressure relief. And after fault processing is finished, the system calculates heat loss according to the energy conservation principle and executes fuel compensation. The method solves the problem that whether the airflow is real pipeline airflow or not cannot be judged in the prior art, and the safety and thermal system stability of blast furnace control are improved.

Description

Technical Field

[0001] This invention relates to the field of airflow control technology, specifically to a blast furnace pipeline airflow control device and control method. Background Technology

[0002] Blast furnace ironmaking is a complex gas-solid phase countercurrent mass and heat transfer process. The gas stream generated by high-pressure hot blast and injected fuel must pass through the descending burden layer during its ascent. Under normal smelting conditions, the gas stream should be relatively uniformly distributed across the furnace cross-section. However, when the shape of the softening zone changes or the permeability of the edge burden layer deteriorates, the resistance in localized areas decreases. The high-speed gas stream then concentrates and penetrates this burden layer, forming a low-resistance channel—a phenomenon known in the industry as "pipeline gas flow." The continuous presence of pipeline gas flow leads to reduced gas energy utilization, imbalanced gas stream distribution at the furnace top, and disordered tuyeres. In severe cases, it can threaten the smooth operation of the blast furnace. Therefore, timely detection and elimination of pipeline gas flow is a critical aspect of blast furnace operation.

[0003] Existing blast furnace control systems are typically equipped with a furnace top pressure monitoring device and an anti-surge valve actuator linked to it. In conventional control logic, the system monitors the total pressure at the furnace top in real time via a pressure transmitter installed at the furnace top and compares the collected pressure value with a preset safe pressure upper limit. When the monitored furnace top pressure exceeds the set threshold, the control system determines that a pressure anomaly has occurred and then outputs a command to activate the anti-surge valve on the blower outlet pipe, rapidly reducing the amount of air entering the furnace by discharging some of the blower air into the atmosphere. This method of suppressing airflow erosion by reducing the kinetic energy of the blower air is currently the main way to handle high-pressure anomalies inside the furnace in industrial settings.

[0004] However, existing technologies that rely solely on a single threshold for determining the total pressure at the furnace top have significant limitations. Their core flaw lies in their inability to effectively distinguish abnormal operating conditions caused by gas flow in the pipelines. In actual production, misjudging a pressure increase as a sign of gas flow in the pipelines and triggering the anti-surge valve for drastic pressure relief can lead to a sudden loss of gas support for the blast furnace column, potentially causing large-scale collapses or severe burn accidents. This violent mechanical impact can cause irreversible damage to the blast furnace structure and auxiliary equipment. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a blast furnace pipeline airflow regulation device and control method, which solves the technical problems of high misjudgment risk, inability to identify true pipeline airflow, and lack of quantitative heat compensation mechanism after a fault in existing blast furnace pipeline airflow control technologies.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a blast furnace pipeline airflow regulation device and control method, comprising a detection unit, a central control unit, and an actuator. The detection unit includes first to fourth pressure transmitters arranged on the four gas riser pipes at the top of the blast furnace, used to collect real-time pressure distribution data at the top of the furnace in four directions; the detection unit is also equipped with a thermocouple temperature sensor for measuring the top temperature and a position transmitter for measuring the actual opening angle of the anti-surge valve. The actuator includes an anti-surge valve assembly installed on the blast furnace blower outlet duct and the atmospheric communication pipe, and an electro-hydraulic servo or pneumatic piston actuator for driving the valve. The central control unit is connected to the aforementioned sensors and actuator via signals, used to receive real-time operating data and output control commands, thereby realizing the monitoring and regulation of the blast furnace airflow state.

[0007] A second aspect of this invention provides a blast furnace pipeline airflow control method. This method, based on the aforementioned device, focuses on achieving precise identification and closed-loop control of operating conditions through multi-dimensional pressure field analysis. The method comprises six main stages: data acquisition, pressure distribution calculation, operating condition determination, execution control, pressure recovery, and heat compensation. In the data acquisition and pressure distribution calculation stage, the system acquires real-time pressure values ​​from four directions, calculates the average pressure at the furnace top, and the spatial dispersion reflecting the degree of pressure distribution unevenness. Spatial dispersion is a key parameter for distinguishing different abnormal operating conditions, and its calculation is based on the principle of mean square error in statistics. Specifically, let the real-time pressures at the four directions be P1, P2, P3, and P4, and the average pressure at the furnace top be... Then the formula for calculating the spatial dispersion S is expressed as:

[0008] In addition, the system calculates the difference between the spatial dispersion at the current moment and the spatial dispersion in the previous period, divides it by the sampling period, and obtains the rate of change of spatial dispersion, which is used to determine the development trend of airflow turbulence.

[0009] In the stage of determining the operating condition, this invention adopts a step-by-step determination logic. First, it determines whether the average pressure at the furnace top has exceeded the limit, i.e., it determines... Does it exceed the furnace top set pressure P? set Pressure deviation threshold ΔP th The sum of these conditions, i.e., an early warning signal is only issued when the pressure is greater than or equal to 8 kPa. When the total pressure exceeds the limit, the operating condition is further qualitatively characterized based on the spatial dispersion S. If S is less than the preset spatial dispersion threshold S set This indicates that although the pressure inside the furnace has increased, it is evenly distributed, and is judged to be in normal operating condition. At this time, it is forbidden to open the anti-surge valve to avoid accidentally opening the air valve under normal conditions, which would cause a sudden drop in air volume and trigger a material impact.

[0010] If S is greater than or equal to the spatial dispersion threshold S set Alternatively, in dynamic trend determination, when S reaches a certain proportion of the threshold and the rate of change of spatial dispersion exceeds the preset growth rate, it indicates that a local airflow channel has appeared in the furnace, and it is determined to be a true pipeline airflow condition. At this time, the system outputs a first-level control command to drive the anti-surge valve to open.

[0011] During the control execution phase, for actual pipeline airflow conditions, the system uses a variable gain model to calculate the target opening degree of the anti-surge valve, achieving rapid pressure relief. Target opening degree θ target The calculation logic is as follows:

[0012] Among them, K P θ is the proportional gain coefficient. min To overcome the minimum effective operating opening of the valve dead zone, the anti-surge valve directly steps to the target opening and locks after receiving the command, until the pressure drops back to the normal range. During the pressure recovery phase, the system introduces a pressure recovery rate monitoring mechanism to prevent secondary pressure buildup caused by excessively rapid valve closure. The system calculates the rate of pressure change over time, and only allows the anti-surge valve to gradually close in preset steps when the absolute value of the pressure recovery rate is less than or equal to the pressure fluctuation safety threshold; otherwise, the closing operation is paused, and the current opening is maintained. In addition, during the re-airing process after the valve is fully closed, the system generates an air volume step sequence and controls the graded loading of air volume based on three constraints: dynamic pressure upper limit, spatial dispersion, and pressure change rate. If any condition is not met, the system automatically retracts. In the heat compensation phase, this invention solves the furnace temperature fluctuation problem after a fault based on the principle of energy conservation. The system first determines the fault duration [t]. start ,t end Based on the opening characteristic curve and rated flow coefficient of the anti-surge valve, the total heat deficit Q during the fault period is calculated by integration. loss The computational logic is expressed as follows:

[0013] Among them, F set To set the airflow normally, F real F represents the measured flow rate at the blower outlet. leak (t) represents the instantaneous leakage flow rate of the anti-surge valve, H valThis is the sum of the physical heat and chemical reaction heat brought in per unit volume of blower. The system converts the total heat deficit into an equivalent amount of coke compensation and implements a graded compensation strategy based on the degree of deficit: minor deficits are compensated by increasing the pulverized coal injection rate; moderate deficits are compensated by adding clean coke; and severe deficits are compensated by adding clean coke while adjusting the batching matrix of subsequent shifts. For moderate and severe deficits, the system also uses pressure distribution data to identify abnormal locations and controls the material distribution equipment to perform point-to-point compensation at the abnormal locations, achieving precise repair of the thermal field.

[0014] This invention provides a blast furnace pipeline airflow regulation device and control method. It has the following beneficial effects: 1. This invention solves the technical problem of traditional single pressure threshold judgment failing to identify true pipeline airflow by introducing spatial dispersion calculation logic. When the average pressure at the furnace top exceeds the limit, the system further detects the uniformity of pressure distribution in four directions. Only when the dispersion exceeds the threshold, indicating the existence of local airflow channels, will the anti-surge valve be opened to relieve pressure. This judgment mechanism effectively avoids the accidental opening of the air valve under normal conditions, which could lead to a sudden drop in furnace pressure and cause a charge impact accident, significantly improving the safety of the blast furnace in dealing with abnormal operating conditions.

[0015] 2. This invention employs a closed-loop control strategy combining a variable gain calculation model based on the degree of pressure exceeding limits with pressure recovery rate monitoring. In the initial stage of gas flow instability, the controller automatically calculates the target opening degree based on the deviation between the real-time pressure and the set value, driving the actuator to respond quickly to suppress the development of gas flow in the pipeline. During the pressure recovery phase, the system monitors the pressure change rate in real time; once the change rate exceeds a safety threshold, the shut-off operation is paused. This control method ensures both the timeliness and targeted nature of pressure relief and prevents the gas flow inside the furnace from fluctuating again or causing secondary pressure buildup due to excessively rapid valve closure, thus ensuring the stability of the blast furnace operating condition leveling process.

[0016] 3. This invention establishes a quantitative heat compensation mechanism based on the principle of energy conservation, changing the traditional reliance on manual experience to estimate compensation amounts. The system calculates the effective air volume loss caused by anti-surge valve leakage during a fault through integration, accurately converting it into a total heat deficit. Based on the deficit level, it automatically matches and adjusts tiered compensation measures such as pulverized coal injection, net coke production, or material variation regime. Combined with point-to-point material distribution compensation using anomaly location indexing, it can specifically repair the thermal field distribution in damaged areas, minimizing the impact of pipeline airflow faults on the subsequent blast furnace smelting thermal regime. Attached Figure Description

[0017] Figure 1 This is a flowchart of the gas flow control method for the blast furnace pipeline. Detailed Implementation

[0018] 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

[0019] Please see the appendix Figure 1 This invention provides a blast furnace pipeline airflow regulation device and control method, including a detection unit, a central control unit, and an actuator. The detection unit is equipped with a physical quantity acquisition device for the airflow distribution and energy state at the top of the blast furnace; The detection unit includes a multi-point pressure monitoring component for acquiring pressure field distribution data at the blast furnace top. Four pressure transmitters—a first, second, third, and fourth—are independently installed on four gas riser channels evenly distributed along the circumference of the blast furnace top. The first pressure transmitter is installed on the east-facing riser, and the acquired real-time pressure value is defined as P1. The second pressure transmitter is installed on the south-facing riser, and the acquired real-time pressure value is defined as P2. The third pressure transmitter is installed on the west-facing riser, and the acquired real-time pressure value is defined as P3. The fourth pressure transmitter is installed on the north-facing riser, and the acquired real-time pressure value is defined as P4. To ensure accuracy when calculating the spatial dispersion S, the first, second, third, and fourth pressure transmitters employ a synchronous trigger acquisition mode, ensuring that P1 to P4 are instantaneous pressure values ​​at the same moment. The range of the first to fourth pressure transmitters is set to 0 to 1.5 times the design working pressure of the blast furnace top, in order to cover the range of instantaneous pressure surges that may occur when gas flow occurs in the pipeline.

[0020] The detection unit includes a temperature monitoring component for monitoring the thermal status of the blast furnace. The temperature monitoring component uses thermocouple temperature sensors installed at the top gas outlet main or riser junction of the blast furnace. The thermocouple temperature sensors acquire the top gas temperature in real time, and the acquired real-time top temperature value is defined as TT. The thermocouple temperature sensors are selected from wear-resistant, armored thermocouples with a response time of less than 1 second to meet the requirement of capturing instantaneous temperature changes during gas flow in the pipeline. The top temperature TT serves as the direct input for subsequent calculations of fuel ratio increments and determination of coking quantity levels.

[0021] The detection unit includes a valve position monitoring component for feedback on the actuator's operational status. The blast furnace blower unit is equipped with an anti-surge valve to regulate the air supply volume. The valve position monitoring component, via a position transmitter mechanically connected to the anti-surge valve stem, acquires the actual opening angle of the anti-surge valve in real time. The position transmitter converts the physical opening degree of the anti-surge valve into a digital opening degree signal from 0 to 100% and transmits it to the central control unit. The real-time acquired anti-surge valve opening degree signal is used to calculate the cumulative air volume loss during the anti-surge valve's opening process, providing a basis for calculating the air volume loss correction coefficient for the thermal compensation model.

[0022] The aforementioned first, second, third, and fourth pressure transmitters, thermocouple temperature sensor, and position transmitter are connected to the analog input module of the central control unit via shielded signal cables. Considering the presence of pulse interference at the blast furnace site, the detection unit performs a moving average filtering process with a time window of 0.5 to 1.0 seconds on the P1 to P4 and TT data before transmitting the raw signals to the processing logic. This filtering process removes random high-frequency noise while preserving the abrupt changes in pressure and temperature signals, ensuring that the subsequent identification algorithm can effectively extract the characteristics of the pipeline airflow within 2 seconds.

[0023] The central control unit, as the computational core of the intelligent blast furnace pipeline airflow control system, physically adopts a process control station of a programmable logic controller (PLC) or distributed control system. The process control station is internally equipped with a central processing unit (CPU), memory, analog input / output modules, and digital input / output modules. The memory stores computer program instructions for executing the blast furnace pipeline airflow control logic, and the CPU executes these instructions to achieve the following data processing and control functions.

[0024] The central control unit is equipped with a data preprocessing module. This module receives real-time pressure signals from the first, second, third, and fourth pressure transmitters, as well as temperature signals from thermocouple temperature sensors, via analog input channels. The central control unit synchronously reads the values ​​of P1, P2, P3, P4, and TT according to a preset control cycle, such as 100 milliseconds to 500 milliseconds, and temporarily stores the read values ​​in a data register. Internally, the central control unit operates duct airflow identification and calculation logic, which is used to quantitatively evaluate the spatial distribution of airflow within the furnace.

[0025] The central control unit calls the calculation instructions to calculate the actual working pressure value K1 at the top of the blast furnace. The actual working pressure value K1 at the top of the blast furnace is the arithmetic mean of the pressure values ​​in four directions. The calculation formula is as follows:

[0026] Among them, P1, P2, P3, and P4 are the real-time pressure detection values ​​in the four directions of east, south, west, and north, respectively.

[0027] The central control unit calculates the spatial dispersion S of the furnace top pressure field. The spatial dispersion S characterizes the degree of deviation of the pressure values ​​in four directions from the average value. In this embodiment, the spatial dispersion S is calculated using the mean square error algorithm, and the calculation formula is as follows:

[0028] Among them, P i K1 represents any one of the pressure detection values ​​from P1 to P4, and K1 is the average pressure value calculated above.

[0029] The central control unit's memory stores the preset blast furnace top pressure value K0 and pressure deviation threshold ΔP during normal blast furnace production. set and the spatial dispersion threshold S set Spatial dispersion threshold S set The value is determined based on the statistical distribution characteristics of historical pressure data under normal blast furnace conditions. It is usually set to 3 to 5 times the standard deviation of pressure under normal operating conditions, such as 1.5 kPa to 3.0 kPa.

[0030] The central control unit performs a logical comparison between the real-time calculated K1 and S and the set parameters. Specifically, the comparison logic is as follows: determine whether K1 - K0 is greater than or equal to ΔP. set And at the same time, determine whether S is greater than or equal to S. set When both conditions are met simultaneously, the central control unit determines that the blast furnace is currently in a true pipeline gas flow state and generates a first-level control command to trigger the pressure relief operation; when only K1-K0 is greater than or equal to ΔP... set But S is less than S set At this time, the central control unit determines that the blast furnace is in a normal state, does not generate a first-level control command, and considers the blast furnace status normal, requiring no action. The central control unit is equipped with an adaptive recovery control module, which is used to monitor the furnace condition recovery process after the depressurization operation.

[0031] When K1 is detected to fall below the value of K0, the central control unit calculates the pressure recovery rate V based on continuous time-series pressure data. P The calculation formula is as follows:

[0032] Where K1(t) is the average pressure value at the current moment, and K1(t-Δt) is the average pressure value at the previous calculation moment. To avoid distortion of the differential calculation due to signal noise, the calculation time interval Δt is set to 1 to 5 seconds, or a moving average is applied to K1(t) and K1(t-Δt) before differential calculation. The central control unit will then calculate the pressure recovery rate V. P The absolute value of the pressure fluctuation safety threshold V safe Comparison, only in V P The absolute value is less than or equal to V safe At that time, a secondary control command is generated that allows the anti-surge valve to gradually close; if V P The absolute value is greater than V safe The central control unit outputs a command to maintain the current anti-surge valve opening, pausing the closing operation until pressure fluctuations stabilize. The central control unit also includes a thermal compensation calculation module, which recalculates the physical heat loss caused by airflow in the pipeline based on the principle of energy conservation.

[0033] The thermal compensation calculation module records the peak furnace top temperature T during the gas flow in the pipeline. peak And the integral value of airflow loss during the opening process of the anti-surge valve. The thermal compensation calculation module is based on the peak furnace top temperature T. peak Calculate the base fuel ratio increment and combine it with the integral value of air volume loss to output the final recommended value for coke replenishment.

[0034] The central control unit connects to the actuator via an analog output module or fieldbus communication interface, converting the generated primary and secondary control commands into standard electrical signals that drive the anti-surge valve. The central control unit ensures that the time delay from the fulfillment of the judgment condition to the output of the primary control command is controlled within 2 seconds to meet the process requirement of rapidly suppressing pipeline airflow. The specific selection of the programmable logic controller or distributed control system and the programming language implementation can be configured according to actual industrial site standards by those skilled in the art, and are well-known technologies in the field, so they will not be elaborated further here.

[0035] The actuator is responsible for responding to control commands issued by the central control unit and changing the energy input state of the blast furnace blast system by adjusting the bypass gas flow.

[0036] The actuator includes an anti-surge valve assembly installed on the pipeline connecting the blast furnace blower outlet duct to the atmosphere. This anti-surge valve assembly is a key component for achieving rapid and directional pressure relief at the blast furnace top. To meet the requirement of precise suppression during the initial gas flow stage, the anti-surge valve assembly uses a regulating butterfly valve or eccentric rotary valve with linear flow characteristics or corrected equal percentage flow characteristics. The valve plate structure design of the regulating butterfly valve or eccentric rotary valve must ensure a monotonically increasing linear relationship between the flow area and the opening degree within a small opening range of 0% to 10%, avoiding flow dead zones or sudden flow changes at small openings, thereby ensuring that a 5% set opening degree corresponds to a stable pressure relief air volume.

[0037] The anti-surge valve assembly is equipped with a high-response electro-hydraulic servo actuator or a pneumatic piston actuator in its drive mechanism. To support rapid action from fully closed to the set opening degree within 2 seconds, the electro-hydraulic servo actuator is equipped with a high-pressure accumulator module, and the pneumatic piston actuator is equipped with a large-diameter fast exhaust valve and an air booster tank. The accumulator module or air booster tank can instantly release high-pressure fluid energy to overcome the aerodynamic resistance torque in the high-pressure air duct, achieving instantaneous valve response.

[0038] The actuator is equipped with an intelligent valve positioner. The intelligent valve positioner receives 4mA to 20mA analog control signals or HART / Profibus bus digital commands from the central control unit via a shielded signal cable. An integrated position feedback sensor collects the actual physical position of the valve stem in real time. The intelligent valve positioner compares the actual physical position with the 5% target opening command issued by the central control unit in real time, and adjusts the output pressure of the drive fluid using an inner-loop PID algorithm to ensure that the steady-state positioning accuracy deviation of the anti-surge valve assembly is controlled within ±0.1%. Furthermore, the intelligent valve positioner has preset priority logic; when it receives an anti-surge protection signal from the blower's safety system, the intelligent valve positioner prioritizes executing the blower's anti-surge protection action to ensure the safety of the blower unit.

[0039] The actuator also includes a local control box. This box is connected in series in the control loop of the anti-surge valve assembly and is equipped with a remote / local switch and an emergency shut-off button. When the system enters the adaptive recovery phase but an abnormal pressure rebound occurs that cannot be automatically eliminated, field personnel can use the local control box to cut off the signal path to the central control unit, forcing the anti-surge valve assembly to close or maintain its current position. This serves as a physical redundancy safety guarantee for the automatic control logic. The human-machine interface (HMI) runs on the industrial computer terminal in the blast furnace main control room, interacting with the central control unit in real time via OPC or Modbus TCP / IP protocols. The HMI provides a visual operation window and parameter setting platform, allowing operators to monitor system operation and intervene in parameters.

[0040] The human-computer interface includes a real-time monitoring overview area. This area graphically displays the real-time pressure distribution at four locations on the blast furnace top. Specifically, it displays a radar chart or bar chart, with the four data points corresponding to the real-time values ​​P1, P2, P3, and P4 of the first, second, third, and fourth pressure transmitters, respectively. The calculated spatial dispersion S and the average pressure value K1 are displayed in the center of the graph. When the spatial dispersion S exceeds a set threshold S0... set At that time, the color of the corresponding data element in the real-time monitoring overview area changes from green to red. Simultaneously, the real-time monitoring overview area displays the current opening status of the anti-surge valve, the real-time trend curve of the furnace top temperature TT, and the pressure recovery rate V. P The dynamic value.

[0041] The human-machine interface includes a system operation mode control area. This area contains selectors for automatic monitoring mode, automatic control mode, and manual maintenance mode. In automatic monitoring mode, the system only performs calculations and alarms, without outputting control commands. In automatic control mode, the system automatically performs pressure relief and recovery operations based on logic. In manual maintenance mode, the system logic is bypassed, allowing operators to manually test the anti-surge valve's operation. This tiered design ensures the system's adaptability and safety under different operating conditions.

[0042] The human-machine interface includes a parameter configuration area. This area is only accessible to users with engineer privileges and is used to set and modify critical threshold parameters for system operation. The parameter configuration area includes an input box for the furnace top set pressure value K0 and a pressure deviation threshold △P. set Input box, spatial dispersion threshold S set Input box, anti-surge valve opening setting box, pressure recovery rate safety threshold V safe The input box and the thermal compensation calculation coefficient configuration table are provided. Through the parameter configuration area, process engineers adjust the above parameters according to the blast furnace raw material conditions and smelting intensity.

[0043] The human-machine interface includes alarm and history sections. The alarm and history section lists all alarm information generated by the system, including timestamps and details of alarm events such as true pipeline airflow triggering and anti-surge valve timeout. The alarm and history section automatically records the entire process data before and after each pipeline airflow event, including raw data from P1 to P4, anti-surge valve activation duration, pressure recovery curves, and the system-calculated thermal compensation recommendations. This historical data is stored on the hard drive as a database file and can be exported to Excel or CSV format.

[0044] The human-machine interface integrates a heat compensation operation guidance module. After the system completes a pipeline airflow processing procedure, the heat compensation operation guidance module displays a pop-up window showing the heat loss assessment report for this event. The report includes the peak furnace top temperature T. peak The system calculates the fuel ratio increment ΔR and recommends the coke replenishment level. The thermal compensation operation guidance module includes confirmation and manual correction buttons. When the operator clicks the confirmation button, the human-machine interface sends a digital command containing the specific coke replenishment weight to the blast furnace trough feeding control system via the communication interface. When the operator clicks the manual correction button, the human-machine interface allows the operator to input the corrected coke replenishment value and sends the corrected value to the blast furnace trough feeding control system, achieving closed-loop feeding compensation control.

[0045] In step S100, the system performs real-time data acquisition. The detection unit synchronously acquires real-time pressures P1, P2, P3, and P4 at four locations on the blast furnace top, as well as the furnace top temperature TT and the real-time opening degree U of the anti-surge valve, according to a preset sampling frequency. V The acquired analog signals are filtered and converted into digital signals, which are then input to the central control unit.

[0046] In step S200, the central control unit performs parameter calculations on the collected pressure data. The central control unit calculates the parameters according to the formula... Calculate the average pressure K1 at the current furnace top, and apply the formula... The spatial dispersion S, reflecting the degree of pressure distribution non-uniformity, is calculated. Simultaneously, the central control unit reads the set parameters from the memory, including the furnace top set pressure K0 and the pressure deviation threshold ΔP. set and spatial dispersion threshold S set .

[0047] In step S300, the system determines whether the average pressure at the furnace top has increased abnormally. The determination logic condition is K1-K0≥△P setIf the result of step S300 is negative, it indicates that the furnace top pressure is within the allowable fluctuation range, and the system returns to step S100 to continue monitoring for the next cycle. If the result of step S300 is positive, it indicates that the permeability inside the furnace has deteriorated, and the system proceeds to step S400 to perform qualitative identification of the airflow pattern.

[0048] In step S400, the system executes airflow pattern identification logic. The central control unit determines whether the calculated spatial dispersion S satisfies the condition S≥S set This judgment is used to identify fault conditions in the actual pipeline airflow. If the judgment result of step S400 is negative (i.e., S < S), then... set If the system determines that the current operating condition is normal, it proceeds to step S500; if the result of step S400 is yes (i.e., S≥S), then the system proceeds to step S500. set The system determines that the current operating condition is a true pipeline airflow and proceeds to step S600.

[0049] The central control unit sends a warning signal when the pressure is greater than or equal to 8 kPa, prompting the operator to check the movement status of the measuring tape. After completing step S500, the current cycle ends, and the system returns to step S100.

[0050] In step S600, the system performs an automatic interlock suppression operation. The central control unit outputs a first-level control command, driving the anti-surge valve to open to a preset 5% opening degree within 2 seconds. After the anti-surge valve is in place, the central control unit locks the opening state and continuously monitors the value of the furnace top average pressure K1. The system maintains the anti-surge valve in the open state until it detects that K1 has fallen back below the set pressure K0.

[0051] In step S700, the system performs adaptive recovery control. When the condition K1 < K0 is met, the central control unit calculates the pressure recovery rate V. P And determine |V P |≤V safe The system checks whether the condition is met. If the condition is met, the central control unit controls the anti-surge valve to perform a closing action according to a preset step size; if the condition is not met, the central control unit controls the anti-surge valve to maintain its current opening and pauses the closing action. The system repeats the above judgment and action in each control cycle until the opening U of the anti-surge valve is reached. V Reset to zero.

[0052] In step S800, the system performs a quantitative thermal compensation calculation. After the anti-surge valve is fully closed, the central control unit extracts the peak furnace top temperature T recorded in this process. peakThe system also collects integral data on airflow loss during the opening of the anti-surge valve. The central control unit calculates the required fuel ratio increment ΔR based on a preset energy conservation model and determines the coking level based on ΔR. Finally, the system outputs the coking suggestion to the human-machine interface or sends it to the batching system, completing the closed-loop processing of this abnormal operating condition.

[0053] The data preprocessing stage follows immediately after the acquisition of the original sensor signals. As the input stage of the core algorithm, it is used to ensure the spatiotemporal consistency and signal purity of the pressure data involved in the calculation.

[0054] In step S101, the system performs synchronous sampling and time alignment of multi-channel data. The central control unit sends a synchronization trigger command to the analog-to-digital conversion module. The analog-to-digital conversion module locks the analog voltage signals of the first, second, third, and fourth pressure transmitters within the same clock cycle and converts the analog voltage signals into digitized raw pressure values ​​P. raw,1 (t), P raw,2 (t), P raw,3 (t), P raw,4 (t). The analog-to-digital conversion module uses hardware latches to control the sampling time deviation of the four channels to within 10 microseconds. This microsecond-level synchronization mechanism ensures that the pressure data in the four directions are strictly aligned on the physical time axis, eliminating the time phase error caused by the high-frequency pulsation of the gas flow inside the blast furnace (usually between 1Hz and 5Hz), thus ensuring the accuracy of subsequent spatial dispersion calculations.

[0055] In step S102, the system performs outlier removal. The data preprocessing module uses a first-order differential amplitude limiting algorithm to process the P data obtained in step S101. raw,i (t) performs filtering. The algorithm calculates the absolute value of the difference between the current sampled value and the valid value at the previous time step, and compares it with the preset physical rate of change limit R. lim The comparison is performed. The determination formula is as follows:

[0056] Among them, P raw,i (t) represents the original sampled value of the i-th channel at the current time, P valid,i (t-1) is the effective value of the i-th channel at the previous time step, R lim This is the maximum allowable rate of change based on the physical properties of blast furnace pressure, for example, 5 kPa / s. If the above inequality holds, the data preprocessing module determines P... raw,i (t) represents spurious data caused by electrical interference, and P is... raw,i (t) is replaced with P valid,i (t-1); if the inequality does not hold, the data preprocessing module will P raw,i (t) is assigned to Pvalid,i (t).

[0057] In step S103, the system performs a moving average filtering process. The data preprocessing module constructs a data buffer window of length N. In this embodiment, N takes the value of 5 to 10, corresponding to a time span of 0.5 seconds to 1.0 seconds. The data preprocessing module calculates the filtered pressure value P according to the following formula. filt,i (t):

[0058] Among them, P valid,i (t-j) represents the effective pressure value at time t-j in the data cache window. Through the processing in step 5103, the system filters out high-frequency noise caused by random turbulence in the gas flow, retaining the low-frequency pressure trend characteristics reflecting changes in the permeability of the material column, providing smooth input data for parameter calculation in step S200. In step S104, the system performs sensor status validity verification and fault-tolerant degradation processing. The data preprocessing module will... filt,i (t) and the physical range of the sensor [P] min ,P max Compare P. filt,i (t) If the value exceeds the physical range or remains stable for M consecutive cycles, the data preprocessing module marks the channel as faulty. When a channel is detected as faulty, the system automatically initiates a three-point degradation calculation mode. In this mode, the data preprocessing module removes the faulty channel data and calculates the corrected average pressure using the valid data from the remaining three channels. and the corrected spatial dispersion This replaces the conventional calculation in step S200. The revised calculation formula is as follows:

[0059] Where Ω represents the set of the remaining three valid channels, and C correct This is a downgrade correction factor, with a value ranging from 1.1 to 1.3. C correct This is used to compensate for the decrease in spatial representation capability caused by the reduction in sampling points, ensuring that the calculated dispersion value can still be consistent with the threshold S in step S400 under sensor failure conditions. set The order of magnitude must remain consistent. If the number of faulty channels is greater than or equal to two, the data preprocessing module will output a system fault alarm and forcibly stop the automatic control function.

[0060] This calculation process corresponds to step S200 in the overall logical flow and is executed by the mathematical operation logic module inside the central control unit. This step mainly processes the standard pressure vector group output from step S104, where all four channels are valid; if step S104 indicates that the system is in a three-point degradation operation mode, then the calculation result from S104 is directly called. and It will participate in subsequent logic and will no longer perform the standard calculations of this step.

[0061] In step S201, the central control unit performs the calculation of the average working pressure of the entire furnace. When the system status register indicates that all four pressure sensors are working normally, the central control unit calls the arithmetic mean calculation instruction to average the filtered pressure values ​​from the four directions to obtain the average pressure value K1 at the top of the blast furnace. The calculation formula is as follows:

[0062] Among them, P filt,i (t) represents the preprocessed effective pressure data at the i-th position at the current moment. The average pressure value K1 at the top of the blast furnace represents the overall permeability resistance level of the blast furnace burden at the current moment.

[0063] In step S202, the central control unit performs a pressure field spatial dispersion calculation. In normal mode, to distinguish between the non-uniform pressure distribution caused by localized pipe airflow and the uniform pressure increase caused by the overall material suspension, the central control unit uses the root mean square error algorithm to construct the spatial dispersion index S. The calculation formula is as follows:

[0064] Among them, P filt,i (t) represents the filtered pressure value at each direction, and K_{1} represents the average pressure value calculated in step S201. In this formula, (P filt,i (t)-K1) represents the degree of pressure deviation in a single direction. By squaring the degree of deviation, the algorithm increases the weight of larger deviations on the final result. When a single strong duct airflow occurs in the furnace, the pressure data deviation in the corresponding direction increases, resulting in a significant increase in the spatial dispersion index S. When there is overall material suspension in the furnace, although the pressure values ​​in all four directions increase, the deviations of the values ​​in each direction relative to the average value K1 are small and evenly distributed, and the calculated spatial dispersion index S remains at a low level.

[0065] In step S202, the central control unit also calculates the rate of change of spatial dispersion, dS / dt. The central control unit calculates the difference between the spatial dispersion S(t) at the current time and the spatial dispersion S(t-1) in the previous calculation period, and divides it by the sampling period ΔT. The calculation formula is:

[0066] The rate of change of spatial dispersion, dS / dt, reflects the development trend of airflow turbulence. This parameter will serve as an auxiliary criterion in subsequent steps to determine whether the duct airflow is in a rapid development phase, and will be used to trigger an early warning when S has not yet reached the threshold but is increasing extremely rapidly.

[0067] In step S203, the central control unit performs abnormal orientation identification and qualitative analysis. The central control unit calculates the relative deviation vector D for each orientation. i =P filt,i (t)-K1. The central control unit not only compares each direction |D i The absolute value of | is used to determine its sign and direction. If |D| is in a certain direction, the sign and direction are also determined. i |Maximum and D i <0, the location is determined to be a low-pressure pipeline area, i.e., an area where airflow short-circuiting occurs; if a certain location |D i |Maximum and D i If the value is greater than 0, the location is determined to be a high-pressure, dense area, i.e., the area with the worst air permeability. The central control unit will then use the identified location index L... index The qualitative results, whether for the piping area or the dense area, are written into the status register to drive the display of the human-machine interface and serve as the basis for determining whether the heat loss is local or total furnace heat loss in subsequent heat compensation calculations.

[0068] This process follows the aforementioned spatial dispersion calculation steps and is executed by the central control unit. The dual-determination logic distinguishes between two typical operating states of the blast furnace: normal fluctuation state and true pipeline airflow state, by combining the total pressure threshold and the dispersion morphology threshold.

[0069] In step S300, the central control unit performs the first-level total pressure determination. The central control unit reads the average pressure value K1 at the top of the blast furnace calculated in step 5201 and compares it with the preset pressure reference parameter. The determination formula is as follows:

[0070] Where K0 is the baseline set pressure value under normal operating conditions of the blast furnace, and ΔP set The allowable pressure fluctuation dead zone threshold (≥8kPa).

[0071] If the inequality in step S300 is not true, the central control unit determines that the current furnace condition is in a normal fluctuation state. At this time, the system does not trigger the abnormal handling logic and directly returns to the data acquisition step S100 to monitor the next cycle.

[0072] If the inequality in step S300 holds true, it indicates an abnormal increase in the furnace's permeability resistance. The central control unit generates a first-level pressure warning sign and activates step S400 for a second-level determination. Step S300 filters out minor, non-process-related pressure fluctuations, initiating subsequent morphological analysis only for significant pressure increase events.

[0073] In step S400, the central control unit performs a second-level airflow pattern determination. This step uses the spatial dispersion S and the rate of change of spatial dispersion dS / dt calculated in step S202 to qualitatively identify the physical causes of the pressure increase. The determination logic includes two parallel conditions: Condition A (Static amplitude exceeds limit): Determine if S≥S set Is it true or false? Where S... set This is the preset discreteness alarm threshold.

[0074] Condition B (Deteriorating Dynamic Trend): Judgment (S≥α·S) set And (dS / dt≥R) trend Whether both conditions are met simultaneously. Where α is the trend determination coefficient (ranging from 0.7 to 0.9), R... trend This is the threshold for the dispersion growth rate. Condition B is used to identify pipeline airflow in a rapid development phase, i.e., before the spatial dispersion has fully reached S. set However, the working conditions deteriorated rapidly in a short period of time.

[0075] Based on the above conditions, the central control unit executes the following branch logic and anti-jitter confirmation: Branch 1: Logic for determining airflow in a real pipeline.

[0076] If either condition A or condition B is met, the central control unit determines that the airflow characteristics of a true duct are initially met. To eliminate transient signal interference, the central control unit activates the anti-jitter timer T. pipe If the above conditions are consecutive N conf It always holds true within each control cycle, i.e., T pipe ≥N conf The central control unit officially confirms the current state as a true duct airflow state and immediately triggers step S600 to execute the anti-surge valve automatic interlock suppression. If the condition is not met during the counting process, the central control unit will T pipe Reset to zero.

[0077] Branch 2: Logic for determining normal operating conditions of a blast furnace.

[0078] If (condition A is not met) and (condition B is not met), but a level one pressure warning flag has been generated in step S300, the central control unit determines that the current situation is normal. Similarly, the central control unit starts timer T. hang If this state is in N consecutiveconf It remains constant throughout the control cycle, i.e., T hang ≥N conf The central control unit officially confirms that the current state is normal. In response to this state, the central control unit triggers step S500, outputting a signal to the human-machine interface, but does not trigger the anti-surge valve.

[0079] In step S601, the central control unit calculates the target pressure relief opening degree. Unlike traditional manual operation that relies on experience to set the opening degree, this embodiment uses a variable gain calculation model based on the degree of pressure exceeding the limit. The central control unit dynamically calculates the target opening degree U of the anti-surge valve based on the deviation between the current average pressure K1 at the furnace top and the set pressure K0. target The calculation formula is as follows:

[0080] Among them, U min The minimum effective operating opening (e.g., 3%) is used to overcome valve dead zone; G P This is the proportional gain coefficient, with units of 96 kPa; ΔP set This is a pressure dead zone. To prevent excessive opening from causing blast furnace shutdown, the system is set with a maximum hard limit U. max That is, if the calculated value is greater than U max Then take U target =U max This calculation process ensures that the pressure relief magnitude is positively correlated with the severity of the gas flow in the pipeline, which can effectively suppress the gas flow and avoid large fluctuations in furnace conditions caused by excessive operation.

[0081] In step S602, the central control unit performs rapid response control. To intervene before the pipeline airflow expands further and causes material collapse, the system bypasses the integral and derivative terms of the conventional PID control loop, directly outputting the opening command in pure proportional mode. The central control unit sends a step control signal to the electro-hydraulic actuator of the anti-surge valve, requiring the valve to respond within a specified time T. act From 0% directly to U target The rapid response characteristic here is key to suppressing airflow in the duct, because slow depressurization will be counteracted by the furnace's automatic regulation mechanism, failing to disrupt the steady state of the airflow channel.

[0082] In step S603, the central control unit performs status locking and pressure monitoring. When the anti-surge valve reaches U... targetAfter the valve is positioned, the central control unit cuts off the automatic adjustment circuit, forcing it to remain at a fixed opening. At this time, a portion of the blast furnace blast system's air volume is directly discharged into the atmosphere or clean gas network through the anti-surge valve, causing a decrease in the actual blast kinetic energy entering the furnace. The central control unit continuously monitors the response curve of the furnace top average pressure K1 at a period of 100ms. During the lockout period, if K1 is detected to have not decreased but instead continues to rise above K... safe This indicates that the anti-surge valve alone is insufficient to control the situation, and the system will trigger an emergency blast reduction logic. This process is a routine safety operation of the blast furnace and will not be detailed here. Under normal circumstances, as the anti-surge valve opens, the furnace top pressure K1 will exhibit an exponential decay trend. When K1 is detected to fall below K0, the system determines that the suppression action has been successful and then proceeds to step S700 for adaptive recovery control.

[0083] In step S701, the central control unit calculates the pressure recovery rate. Upon entering the recovery phase, the central control unit calculates the real-time pressure recovery rate V based on the differential formula. P (t):

[0084] Where K1(t) and K1(t-△t) are the average pressures at the top of the furnace at the current time and the previous sampling time, respectively, and △t is the calculation period. V P The value of (t) reflects the dynamic characteristics of the reconstruction of the pressure field inside the furnace as the anti-surge valve closes.

[0085] In step S702, the central control unit executes the rate feedback-based progressive shutdown logic. The central control unit reads the preset safe rate threshold V. safe V safe The setting is related to the effective volume of the blast furnace and the blast energy. Its physical meaning is to define the maximum pressure fluctuation rate that the material column can withstand, which is usually taken as 0.3kPa / s to 0.8kPa / s.

[0086] The central control unit will calculate the absolute value of the pressure recovery rate |V. P (t)|and V safe Compare the results and perform the following branch operations based on the comparison results: Branch 1 (Allowed Action): If |V P (t)|≤V safe This indicates that the current pressure change is within a safe range. The central control unit outputs a command to drive the anti-surge valve to perform a single-step closing operation, with the step size ΔU set to 0.5% to 1.0%. The control command is U. V (t)=U V (t-1)-△U.

[0087] Branch 2 (Pause and Hold): If |V P (t)|>V safe This indicates severe pressure fluctuations inside the furnace. Continuing to close the valve at this point could trigger a secondary gas flow failure. The central control unit controls the anti-surge valve to maintain its current opening degree, i.e., U... V (t)=U V (t-1). The system checks V again in the next control cycle. P (t).

[0088] Branch 3 (Abnormal Rollback): To prevent excessive heat loss due to the system remaining in a paused state for an extended period, the central control unit initiates a timeout monitoring timer T. wait If the anti-surge valve remains in the non-fully closed position for more than the preset time limit T. max If the furnace top pressure K1 is detected to rise again, triggering the first-level pressure warning in step S300, the central control unit will stop the current recovery process and jump back to step S600 to perform interlock suppression, or output a valve jamming / furnace condition recurrence alarm signal to the main control room.

[0089] In step S703, the central control unit performs a complete closure confirmation. Steps S701 and S702 are executed cyclically with a period of Δt. When the feedback opening U of the anti-surge valve... V If the dead zone value is less than or equal to zero, the central control unit outputs a forced full-close command to completely close the anti-surge valve and reset timer T. wait The system then proceeds to the next step, S800, to perform thermal compensation calculations.

[0090] When the blast furnace performs a reduced-blast operation due to a malfunction, resulting in a current blast volume lower than the normal set value, the central control unit executes the step-by-step blast recovery logic described in this step to prevent the blast volume from recovering too quickly and impacting the burden, thus causing a further deterioration in permeability. This logic is activated after the anti-surge valve is fully closed, i.e., after step S703 is completed.

[0091] In step S704, the central control unit calculates the number of re-airflow steps and the target step. The central control unit reads the normal set airflow Q before the fault occurred. target And the current actual air volume Q current If Q current <Q target The central control unit determines the total number of re-air steps N based on the difference ΔQ between the two. step The calculation formula is as follows:

[0092] Among them, Q step The allowable increment for a single air recirculation (e.g., 100m) 3 / min), ceil(·) is the floor function. The central control unit generates a list containing N based on this. step The airflow step sequence of each element [Q1, Q2] 2，…， Q Nstep ], where Q Nstep =Q target .

[0093] In step S705, the central control unit performs graded loading and dynamic steady-state verification. The central control unit starts the re-air interval timer T. interval When T interval When the preset step holding time is reached, the central control unit increases the airflow setpoint to the next step value Q in the sequence. i When the air volume is increased to Q i Then, the central control unit immediately calculates the upper limit of dynamic pressure K under the current air volume. limit (Q i Considering the fundamental physical laws governing the blast furnace permeability index (k-value), the formula for calculating the upper limit of dynamic pressure is as follows:

[0094] Where K1(t0) is the average pressure at the top of the furnace when the previous air volume step is stable, and Q i-1 The air volume is the next higher level, β is the air permeability resistance coefficient, and P is the air volume of the previous level. margin This formula provides a margin for allowable pressure fluctuations. It ensures that the upper pressure limit automatically increases with the increase in airflow, avoiding misdiagnosis of a malfunction due to a natural increase in pressure caused by physical laws.

[0095] The central control unit continuously monitors the following three steady-state determination conditions: Condition 1: K1(t) < K limit (Q i ).

[0096] Condition 2: S(t)<S stable S stable The steady-state dispersion threshold (e.g., S in step S400) set 80% of the total.

[0097] Condition three: That is, the rate of change of pressure is less than the steady-state rate threshold.

[0098] Only when the above three conditions are within a continuous time window T check When all conditions are met simultaneously (e.g., within 60 seconds), the central control unit determines the current airflow step Q. i Verification passed, and timer T has been reset. interval In preparation for entering the next level of airflow Q i+1oIn step 5706, the central control unit executes the re-airflow blocking retraction logic. If at any airflow step Q... i During the holding period, if any of the judgment conditions in step S705 is not met, that is, if there is an abnormal increase in pressure, excessive dispersion, or violent pressure fluctuation, the central control unit will immediately determine that the re-airflow is blocked.

[0099] The central control unit performs an automatic retraction operation, forcibly reverting the airflow setpoint to the previously verified step value Q. i-1 Simultaneously, the central control unit initiates the ventilation interlock state and sets the interlock timer T. lock (For example, 10 minutes). In T lock Before the countdown ends, the central control unit prohibits the air supply operation in step S705 from being executed again and sends an alarm signal of "Air supply obstructed - automatic reversal" to the human-machine interface. This logic forces the system to pause the recovery process when the operating conditions are unstable, waiting for the airflow channel in the furnace to be naturally rebuilt, preventing the recurrence of airflow failure in the pipeline due to forced air supply.

[0100] In step S801, the central control unit determines the time interval for heat integration. The central control unit records the start timestamp t of the fault event. start and end timestamp t end Start timestamp t start Defined as the time point at which the Level 1 pressure warning flag is first set in step S300, i.e., the moment when the blast furnace operating conditions begin to deviate from normal operating conditions. End timestamp t end Defined as follows: in step S703, the anti-surge valve is fully closed and the airflow is restored to the target set value Q. target The time point. The central control unit acquires the time interval [t]. start, t end The sequence of operating data within [ ] includes: real-time blower flow rate Q real (t), anti-surge valve opening feedback U(t), hot air temperature T blast .

[0101] In step S802, the central control unit calculates the instantaneous leakage flow rate of the anti-surge valve. Since the anti-surge valve is typically not equipped with an independent flow meter, the central control unit calculates the leakage flow rate Q based on the valve's opening characteristic curve. vent (t). The calculation formula is as follows:

[0102] Among them, C V P is the valve's rated flow coefficient. cold P represents the measured pressure value of the cold air duct. atm ρ is atmospheric pressure. airLet U(t) be the air density under standard conditions, and U(t) be the normalized valve opening (0-1). f(U(t)) is the opening characteristic function, which adopts a polynomial fitting form depending on the valve type (e.g., linear or equal percentage). , where the coefficient a k The valve's factory specifications are determined using this formula. The central control unit then converts the valve opening signal into a volumetric flow rate value under standard conditions.

[0103] In step S803, the central control unit calculates the effective blast volume. During a fault, the actual effective blast volume Q entering the blast furnace to participate in the reaction is... eff (t) equals the total flow rate at the blower outlet minus the discharge flow rate of the anti-surge valve. The calculation formula is as follows:

[0104] Among them, Q real (t) represents the measured value of the cold air flow meter.

[0105] In step S804, the central control unit performs a total heat deficit integral calculation. The heat input to the blast furnace mainly consists of two parts: the sensible heat brought in by the blast and the heat of chemical reaction generated by coke combustion. Since the reduced blast volume leads to a corresponding reduction in coke combustion, the heat compensation calculation must simultaneously cover both sensible heat loss and chemical heat loss. Based on the law of conservation of energy, the central control unit calculates the total heat deficit H during the entire fault period. loss The integral formula is as follows:

[0106] Wherein: H loss To accumulate heat deficit, the unit is kilojoules (kJ); Q target The normal airflow setpoint before the fault (Nm³ / s); Q eff (t) represents the instantaneous effective furnace air volume calculated in step S803; Δt represents the sampling period (e.g., 1 second); E phy The sensible heat brought in per unit volume of blower air is calculated using the formula E. phy =C P ·(T blast -T ref ), where C P For the specific heat capacity of hot air, T blast T represents the hot air temperature. ref For ambient reference temperature; E chem This is the heat of chemical reaction generated per unit volume of blast furnace air. This value is an empirical constant or can be calculated in real time using a blast furnace heat balance model, and is typically taken as [value missing]. ,in This represents the carbon consumption coefficient corresponding to the oxygen content of the blower air. This represents the heat released per unit of carbon combustion. In simplified mode, (E phy +E chem You can directly obtain experience points.

[0107] This formula quantifies the energy input shortfall caused by insufficient airflow. The central control unit calculates H... loss The numerical value represents the total amount of additional energy required in subsequent operations to maintain a constant thermal state in the furnace hearth.

[0108] Through the aforementioned steps S801 to S804, the central control unit has completed the physical quantification of heat loss. In this part, the central control unit will generate specific fuel compensation control commands based on the calculation results.

[0109] In step S805, the central control unit calculates the equivalent coke compensation amount. The central control unit reads the total heat deficit value H output in step S804. loss And convert it into the physical weight W of standard dry coke. coke＿eq The conversion formula is as follows:

[0110] Among them, Q lhv＿coke η is the lower heating value of coke. thermal W represents the thermal efficiency coefficient of the blast furnace. coke＿eq It represents the weight basis of coke required to theoretically compensate for heat loss during a failure period.

[0111] In step S806, the central control unit performs deficit classification determination and instruction generation. The central control unit presets two classification thresholds: a first compensation threshold W... th1 Second compensation threshold W th2 The central control unit will calculate W. coke＿eq The comparison is made against the above thresholds, and based on the comparison results, the system selects one of the following three different control branches: Branch 1: Slight deficit compensation (coal injection regulation). If W coke＿eq ≤W th1 This indicates a small heat deficit, which can be quickly and dynamically compensated by adjusting the pulverized coal injection rate without changing the coke batch weight. The central control unit calculates the necessary temporary increase in the pulverized coal injection rate, ΔR. coal .

[0112]

[0113] Among them, K replace The coal-coke replacement ratio refers to the weight of coke that can be replaced by 1 kg of pulverized coal, typically taken as 0.75-0.85. injThe preset compensation action time. The central control unit sends a flow setting command to the pulverized coal injection control system, and in the following T... inj Within a given time period, the total pulverized coal injection rate will be increased by ΔR from its original value. coal (Unit: kg / h)

[0114] Branch 2: Moderate Void Deficit Compensation (Net Coke Fixed-Point Compensation).

[0115] If W th1 <W coke＿eq ≤W th2 This indicates a significant heat deficit, which cannot be replenished promptly by pulverized coal injection alone; therefore, clean coke must be added directly. The central control unit calculates the required number of clean coke batches, N, to be added. batch .

[0116]

[0117] Among them, W batch＿std represents the standard coke weight for a single batch, and ceil(·) is the rounding up function.

[0118] When executing the focusing command, the central control unit calls the abnormal orientation index L identified in step S203. index (If a clear duct airflow direction exists). The central control unit sends a fixed-point / fan-shaped material distribution command to the furnace top material distribution control system: When loading this N... batch During batch coke removal, control the fabric chute to operate only at L. index Within the corresponding azimuth angle range (e.g., θ) L Instead of rotating the fabric in a full circle, the fabric is swung at a range of ±15°. This operation concentrates high-calorific-value coke onto areas that previously had abnormal air permeability, achieving targeted thermal field repair.

[0119] Branch 3: Severe deficit compensation (reset of the entire furnace heat system).

[0120] If W coke＿eq >W th2 This indicates a severe imbalance in the blast furnace's thermal state, with the furnace temperature facing a significant risk of decline. At this point, in addition to executing the net coke compensation operation in Branch Two, the central control unit simultaneously triggers a full-furnace thermal regime adjustment.

[0121] The central control unit modifies the batching matrix for the next shift, reducing the set value of the total ore-to-coke ratio (O / CRatio) by ΔR. load (For example, reduce it by 0.1 to 0.2), while simultaneously increasing the target silicon content setting [Si] in the molten iron. target (For example, an increase of 0.1%). The central control unit maintains this load reduction setting until three consecutive hot metal temperature measurements show that the furnace temperature has returned to the normal target range, at which point the raw ore-coke ratio setting is gradually restored.

[0122] 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 blast furnace pipeline airflow control device, characterized in that, Includes a detection unit, a central control unit, and an actuator; The detection unit includes a first pressure transmitter, a second pressure transmitter, a third pressure transmitter, and a fourth pressure transmitter installed on the four gas riser pipes at the top of the blast furnace for acquiring real-time pressure values; the detection unit also includes a thermocouple temperature sensor installed at the gas outlet main pipe or the riser pipe confluence at the top of the blast furnace for acquiring the top temperature; the detection unit also includes a position transmitter installed on the valve stem of the anti-surge valve for acquiring the actual opening angle of the anti-surge valve. The actuator includes an anti-surge valve assembly installed on the pipeline connecting the outlet duct of the blast furnace blower to the atmosphere, and an electro-hydraulic servo actuator or a pneumatic piston actuator for driving the anti-surge valve assembly. The central control unit is connected to the detection unit and the actuator; the central control unit receives real-time pressure values, furnace top temperature and actual opening angle from the detection unit; the central control unit is used to execute the blast furnace pipeline airflow control logic and adjust the opening degree of the anti-surge valve assembly by sending control commands to the actuator.

2. A method for controlling airflow in a blast furnace pipeline, applied to the blast furnace pipeline airflow control device as described in claim 1, characterized in that it includes the following steps: Step S100: The detection unit collects real-time pressure, furnace top temperature, and anti-surge valve opening at four locations on the blast furnace top. Step S200: The central control unit calculates the average pressure at the top of the furnace and the spatial dispersion reflecting the degree of pressure unevenness based on the real-time pressure. Step S300: The central control unit determines whether the average pressure at the furnace top is greater than or equal to the sum of the set pressure at the furnace top and the pressure deviation threshold. If the judgment result is negative, return to step S100; if the judgment result is positive, proceed to step S400. Step S400: The central control unit compares the spatial dispersion with the spatial dispersion threshold to identify the airflow pattern; Step S500: If the comparison result of step S400 shows that the spatial dispersion is less than the spatial dispersion threshold, the central control unit determines that the blast furnace is in normal condition, no action is required, and no control command to drive the anti-surge valve to open is generated. Step S600: If the comparison result of step S400 shows that the spatial dispersion is greater than or equal to the spatial dispersion threshold, the central control unit determines that the blast furnace is in a true pipeline airflow state, outputs a first-level control command to drive the anti-surge valve to open to the target opening degree and lock it until the average pressure at the top of the furnace drops below the set pressure at the top of the furnace. Step S700: After the anti-surge valve is opened, the central control unit calculates the pressure recovery rate and controls the anti-surge valve to close gradually according to the pressure recovery rate; Step S800: After the anti-surge valve is fully closed, the central control unit calculates the total heat deficit during the fault period based on the principle of energy conservation and converts the total heat deficit into a fuel compensation control command.

3. The control method for blast furnace pipeline airflow regulation according to claim 2, characterized in that, In step S200, the specific process by which the central control unit calculates the average pressure at the furnace top and the spatial dispersion is as follows: The central control unit calculates the arithmetic mean of the four real-time pressure values ​​collected by the first, second, third, and fourth pressure transmitters to obtain the average pressure at the top of the furnace. The central control unit calculates the deviation of four real-time pressure values ​​from the average pressure at the top of the furnace, and uses the mean square error algorithm to calculate the spatial dispersion. The central control unit calculates the difference between the spatial dispersion at the current moment and the spatial dispersion in the previous calculation period, and divides the difference by the sampling period to obtain the rate of change of spatial dispersion. The central control unit calculates the relative deviation vectors in each direction and identifies the abnormal orientation index based on the magnitude and sign of the relative deviation vectors.

4. The control method for blast furnace pipeline airflow regulation according to claim 3, characterized in that, In step S400, the central control unit determines that the blast furnace is in a true pipeline airflow state, which also includes dynamic trend deterioration determination logic: The central control unit determines whether spatial dispersion is in a period of rapid development. If the spatial dispersion is greater than or equal to the product of the trend determination coefficient and the spatial dispersion threshold, and the spatial dispersion change rate is simultaneously greater than or equal to the dispersion growth rate threshold, the central control unit determines that the blast furnace is in a true pipeline airflow state. The triggering condition for determining that the blast furnace is in a true pipeline airflow state in step S600 is: the spatial dispersion is greater than or equal to the spatial dispersion threshold, or the spatial dispersion is in a rapid development period.

5. The control method for blast furnace pipeline airflow regulation according to claim 2, characterized in that, In step S600, the specific process by which the central control unit calculates the target opening degree is as follows: The central control unit uses a variable gain calculation model based on the degree of pressure exceeding the limit to calculate the target opening. The central control unit calculates the difference between the average pressure at the top of the furnace and the set pressure at the top of the furnace, subtracts the pressure deviation threshold, multiplies it by the proportional gain coefficient, and adds the minimum effective operating opening to obtain the target opening of the anti-surge valve. The central control unit sends a step control signal to the anti-surge valve, driving the anti-surge valve to directly move to the target opening degree within a specified time.

6. The control method for blast furnace pipeline airflow regulation according to claim 2, characterized in that, In step S700, the specific process of the central control unit controlling the anti-surge valve to gradually close is as follows: The central control unit calculates the pressure recovery rate based on continuous time-series pressure data; The central control unit compares the absolute value of the pressure recovery rate with the preset pressure fluctuation safety threshold. If the absolute value of the pressure recovery rate is less than or equal to the pressure fluctuation safety threshold, the central control unit generates a secondary control command that allows the anti-surge valve to perform a single-step closing operation according to a preset step size. If the absolute value of the pressure recovery rate is greater than the pressure fluctuation safety threshold, the central control unit outputs a command to maintain the current anti-surge valve opening and suspends the closing operation.

7. The control method for blast furnace pipeline airflow regulation according to claim 2, characterized in that, The method for controlling the airflow in blast furnace pipelines also includes the step-by-step blast volume recovery logic in steps S704 to S706: After the anti-surge valve is completely closed, the central control unit determines the total number of steps to restore the air volume based on the difference between the normal set air volume and the actual air volume, and generates an air volume step sequence. The central control unit performs graded loading according to the air volume step sequence. During the period of holding each air volume step, the central control unit calculates the dynamic pressure limit under the current air volume. The central control unit monitors whether the average pressure at the top of the furnace is less than the dynamic pressure upper limit, whether the spatial dispersion is less than the steady-state dispersion threshold, and whether the pressure change rate is less than the steady-state rate threshold. The central control unit allows the system to proceed to the next airflow level only when all of the above conditions are met. If any condition is not met, the central control unit performs an automatic retraction operation and initiates the pause-to-restore airflow command state.

8. The control method for blast furnace pipeline airflow regulation according to claim 2, characterized in that, In step S800, the specific process by which the central control unit calculates the total heat deficit is as follows: The central control unit determines the start and end timestamps of the fault event; The central control unit calculates the instantaneous leakage flow of the anti-surge valve based on the opening characteristic curve of the anti-surge valve and the valve's rated flow coefficient. The central control unit subtracts the instantaneous leakage flow from the real-time blower flow to obtain the effective furnace air volume; The central control unit calculates the difference between the normal set air volume and the effective furnace air volume based on the law of conservation of energy, and combines the physical sensible heat and chemical reaction heat brought in by the unit volume of blower air to obtain the total heat deficit.

9. The control method for blast furnace pipeline airflow regulation according to claim 8, characterized in that, In step S800, the process by which the central control unit converts the total heat deficit into a fuel compensation control command includes: The central control unit divides the total heat deficit by the product of the lower heating value of coke and the thermal efficiency coefficient of the blast furnace to obtain the equivalent coke compensation amount. The central control unit compares the equivalent coke compensation amount with the preset first compensation threshold and second compensation threshold: If the equivalent coke compensation amount is less than or equal to the first compensation threshold, the central control unit selects the slight deficit compensation branch, calculates the incremental increase in the pulverized coal injection rate that needs to be temporarily increased, and sends an instruction to the pulverized coal injection control system to increase the pulverized coal injection flow setting. If the equivalent coke compensation amount is greater than the first compensation threshold and less than or equal to the second compensation threshold, the central control unit selects the moderate deficit compensation branch, calculates the number of net coke batches to be added, and generates a net coke addition instruction. If the equivalent coke compensation amount is greater than the second compensation threshold, the central control unit selects the severe deficit compensation branch, and while executing the net coke addition command, modifies the batching matrix of the next shift to reduce the overall furnace ore-coke ratio setting value and increase the target silicon content setting value of molten iron. When adding coke to compensate for abnormal heat loss from pipeline airflow, the material distribution method shall be implemented according to the gear and angle of the material distribution matrix during normal production.

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