Self-adaptive control method for ignition process of metallurgical sintering machine

Abstract

The invention relates to the technical field of sintering production, in particular to a self-adaptive control method for an ignition process of a metallurgical sintering machine, which comprises the following steps of: acquiring key parameters such as material layer thickness, hearth pressure, sintering machine speed and air box temperature in a sintering machine system in real time, and transmitting acquired data to an ignition control model unit; and parameters such as fuel and air flow and air volume are dynamically adjusted by adopting a self-adaptive optimization algorithm, so that rapid improvement and stable control of the ignition efficiency are realized. According to the method, temperature and fuel in the ignition process are evaluated through a big data analysis technology in combination with actual requirements of the sintering process, and an ignition control strategy is optimized in combination with an intelligent regulation and control algorithm. Aiming at the complexity of an ignition process of the metallurgical sintering machine, an adaptive optimization technology is utilized to realize accurate control of the ignition process, and optimization suggestions are comprehensively given according to an ignition temperature curve and a fuel consumption condition to timely guide an operator to adjust process parameters, so that the ignition efficiency is improved, the energy consumption is reduced, and the sintering quality is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of sintering production, and particularly relates to an adaptive control method for the ignition process of a metallurgical sintering machine. Background Art

[0002] The iron and steel industry is a pillar industry of the national economy and is also a high-energy-consuming and high-pollution industry. Data shows that the energy consumption of the sintering process in China's iron and steel industry accounts for about 12% of the total energy consumption, and the energy consumption of the ignition process accounts for about 10% of the sintering process. Therefore, energy-saving transformation of the sintering ignition link is crucial for the overall energy conservation and consumption reduction of the iron and steel industry. At the same time, as the starting link of the sintering process, the ignition quality directly affects the output and quality of sintered ore. In order to ignite the solid fuel on the surface layer of the mixed material and form an initial combustion zone with an appropriate thickness, the ignition temperature generally needs to reach above 1100°C. If the ignition temperature is too low, the initial combustion zone will be too narrow, the core temperature of the combustion zone will be insufficient, and the high-temperature holding time will be short, which cannot effectively promote the melting of the sintering mixture; while when the ignition temperature is too high, the surface mixture will be over-melted, resulting in the hardening of the material layer, thus affecting the air permeability of the sintering material surface. Therefore, the control of the metallurgical sintering ignition process is an important task for iron and steel enterprises to increase production and save energy and reduce consumption, meeting the requirements of building a conservation-minded society in China.

[0003] Traditional ignition control methods mainly rely on manual adjustment and empirical setting, basically relying on manual operation and manual confirmation, with low automation, low ignition efficiency, and no guarantee of safe operation. Manual ignition operations are prone to ignition failures, thus affecting the production operation rate of the sintering plant and the annual output of sintered ore in the sintering plant.

[0004] Chinese Patent Application CN202411480886.4 discloses a visual detection-based ignition intensity control system and method. In the ignition intensity control method in this application case, the flame image in the ignition furnace is collected by an image acquisition device, and the flame image is analyzed by a control terminal, and the gas or air supply flow rate is automatically corrected according to the analysis result to achieve the optimal roasting effect.

[0005] In the above application solution, a method for controlling ignition intensity based on visual detection is provided, and this method has some disadvantages. First, the flame color is affected by various factors, and relying solely on color analysis may not accurately reflect the ignition intensity, and the image quality may be interfered by ambient light, camera angle, etc. Finally, the stability and durability requirements of the image acquisition device in a high-temperature and high-pressure environment are relatively high. If the device is damaged or affected by environmental factors, the control accuracy may decrease, limiting its application under different production conditions.

[0006] In view of the above defects, the creator of the present invention finally obtained the present invention through long-term research and practice. Summary of the Invention

[0007] The object of the present invention is to solve the problems existing in the traditional ignition process control method of sintering machines, such as low ignition efficiency, high energy consumption, inaccurate control, slow reaction speed, etc., and provides an adaptive control method for the ignition process of metallurgical sintering machines.

[0008] In order to achieve the above object, the present invention discloses an adaptive control method for the ignition process of metallurgical sintering machines, including the following steps:

[0009] S1, collect ignition system data and sintering process parameters;

[0010] S2, preliminarily preprocess the parameter data collected in step S1 at the control terminal, establish a mathematical model of the sintering ignition process, and continuously optimize various control parameters in the ignition process of the sintering machine in combination with the real-time collected data;

[0011] S3, if the ignition parameters do not meet the optimization requirements, adjust the ignition parameters, give a warning of the corresponding level, generate an optimization suggestion, and output a process adjustment suggestion; if the ignition parameters meet the optimization requirements, record and maintain the current ignition state, and output the ignition efficiency.

[0012] In the step S1, the key parameters include the material layer thickness, furnace pressure, sintering machine speed, and wind box temperature. The material layer thickness is used to control the distribution of fuel and the stability of ignition. The furnace pressure is used to reflect the air flow distribution during the ignition process. The sintering machine speed is used to monitor the speed of the sintering machine in real time to ensure the residence time of the material layer and the uniformity of ignition. The wind box temperature is used to analyze the mixing state of the air flow and fuel.

[0013] In the step S2, the preliminary preprocessing includes noise filtering and data correction to ensure the accuracy of the data.

[0014] In the step S2, the mathematical model of the sintering ignition process is as follows:

[0015]

[0016] y(t) = Cx(t) + Du(t)

[0017] Among them, x(t) is the system state vector, u(t) is the control input, including fuel flow rate, air flow rate, and air volume, y(t) is the output, including ignition intensity and fuel efficiency, and A, B, C, and D are the state matrix, input matrix, output matrix, and transfer matrix of the system respectively.

[0018] The control input u(t) is optimized through the following objective function:

[0019]

[0020] where y target (k) is the predetermined target output, λ is the regularization parameter used to balance the magnitude of the control input and the error of the target output, and N is the prediction step; the optimization objective is to make the output parameters during the ignition process as close as possible to the target values while keeping the control input within the allowable range.

[0021] The calculation formula for the fuel flow rate is as follows:

[0022]

[0023] where u1(t) is the fuel flow rate at time t, L(t) is the thickness of the burden layer at the current moment, P(t) is the furnace pressure at the current moment, k1 is the proportionality coefficient between the fuel flow rate and the burden layer thickness and furnace pressure, and α1 is the influence index of the furnace pressure on the fuel flow rate.

[0024] The calculation formula for the air flow rate is as follows:

[0025]

[0026] where u2(t) is the air flow rate at time t, T(t) is the temperature of the wind box at the current moment, P(t) is the furnace pressure at the current moment, k2 is the proportionality coefficient between the air flow rate and the wind box temperature and furnace pressure, and α2 is the influence index of the furnace pressure on the air flow rate.

[0027] The calculation formula for the air volume is as follows:

[0028]

[0029] where u3(t) is the air volume at time t, P(t) is the furnace pressure at the current moment, T avg (t) is the average value of the wind box temperature at the current moment, and T set is the set target value of the wind box temperature, k3 is the proportionality coefficient between the air volume and the furnace pressure and temperature difference, and α3 is the influence index of the temperature difference on the air volume.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] 1. By collecting multiple key parameters (such as burden layer thickness, furnace pressure, and wind box temperature, etc.) during the ignition process of the sintering machine in real time and dynamically adjusting the control parameters in combination with the adaptive control algorithm, the present invention can accurately optimize the ignition process and significantly improve the ignition efficiency. Compared with the traditional method, the present invention avoids the problem of setting fixed parameters relying on experience, making the ignition process more intelligent and flexible, thus greatly improving the ignition efficiency;

[0032] 2. The present invention adopts an adaptive control algorithm to dynamically adjust parameters such as fuel flow rate and air flow rate according to the real-time state of the sintering machine, effectively avoiding the problems of energy waste or incomplete combustion caused by excessive or insufficient fuel supply in the traditional method, thereby greatly reducing energy consumption and reducing the emission of harmful gases, meeting the production requirements of green environmental protection;

[0033] 3. The present invention can accurately adjust the ignition process according to real-time feedback. Once an abnormal change is detected, the system can issue a warning in time and automatically adjust the control strategy, effectively avoiding the situation of unstable sintering quality and low production efficiency caused by human operation delay or untimely response in the traditional control method. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a model algorithm flowchart of an adaptive control method for the ignition process of a metallurgical sintering machine according to the present invention;

[0035] Figure 2 is a graph showing the real-time changes in the opening degrees of the gas valve and the air valve in Embodiment 1 of the present invention;

[0036] Figure 3 is a historical curve graph of the material layer thickness in Embodiment 1 of the present invention;

[0037] Figure 4 is a historical curve graph of the furnace pressure in Embodiment 1 of the present invention;

[0038] Figure 5 is a historical curve graph of the wind box temperature in Embodiment 1 of the present invention;

[0039] Figure 6 is a historical curve graph of the gas flow rate in Embodiment 1 of the present invention;

[0040] Figure 7 is a historical curve graph of the air flow rate in Embodiment 1 of the present invention;

[0041] Figure 8 is a diagram showing the warning content and simple operation in Embodiment 1 of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0042] The present invention provides an adaptive control method for the ignition process of a metallurgical sintering machine. By collecting multiple key parameters in the ignition process of the sintering machine in real time and combining with an adaptive control algorithm, accurate adjustment of the ignition process is achieved. This method effectively improves the ignition efficiency, reduces energy consumption, optimizes the sintering quality, and reduces harmful emissions, making the sintering process more intelligent and automated.

[0043] To achieve the adaptive control of the ignition process, it is first necessary to collect multiple key parameters of the sintering machine. These parameters include the material layer thickness, which controls the distribution of fuel and the stability of ignition; the furnace pressure, which reflects the air flow distribution during the ignition process; the speed of the sintering machine, which monitors the speed of the sintering machine in real time to ensure the residence time of the material layer and the uniformity of ignition; and the temperature of the wind box, which analyzes the mixing state of the air flow and the fuel. After all this data is collected in real time by sensors, it will be input into the control terminal to provide a basis for subsequent data processing and analysis.

[0044] The collected data will first be preliminarily preprocessed at the control terminal, including noise filtering and data correction, to ensure data accuracy. After preprocessing, the control terminal will perform real-time analysis on the data and establish a mathematical model of the sintering ignition process to predict the supply requirements of fuel and air according to the model. The control strategy during the ignition process is mainly based on the relationships of several key parameters: the material layer thickness and fuel distribution, the furnace pressure and air flow distribution, the speed of the sintering machine and combustion time, the temperature of the wind box and gas flow, etc. Through these analyses, the control system can obtain the change trends of each parameter, providing data support for adaptive control, thereby optimizing the ignition uniformity and efficiency of the sintering process.

[0045] The adaptive control algorithm adopts the Model Predictive Control (MPC) method. This method predicts the behavior of the sintering machine in the next period of time by establishing a mathematical model of the sintering machine ignition process and combining the real-time collected data, and optimizes based on this. The sintering machine ignition process can be represented by a state space model:

[0046]

[0047] y(t) = Cx(t) + Du(t) (2)

[0048] In equations (1) and (2), x(t) is the system state vector (such as parameters like temperature, pressure, air flow, etc.), u(t) is the control input (such as fuel flow rate, air flow rate, etc.), and y(t) is the output (such as ignition intensity, fuel efficiency, etc.). Matrices A, B, C, and D are the system state matrix, input matrix, output matrix, and transfer matrix respectively.

[0049] The goal is to solve for the optimal control input u(t) by minimizing an optimization objective function:

[0050]

[0051] In equation (3), y target(k) The predetermined target output, λ is the regularization parameter used to balance the magnitude of the control input and the error of the target output, and N is the prediction step. The optimization objective is to make the output parameters (such as temperature, fuel consumption, etc.) during the ignition process as close as possible to the target values while keeping the control input within the allowable range.

[0052] The adjustment of the fuel flow is mainly carried out according to the thickness of the material layer and the furnace pressure. The thickness of the material layer directly affects the stability and efficiency of ignition, while the furnace pressure reflects the state of the air flow distribution and affects the mixing degree of fuel and air. The formula for calculating the fuel flow is as follows:

[0053]

[0054] In Equation (4), u1(t) is the fuel flow at time t (unit: kg / s or Nm 3 / s), L(t) is the thickness of the material layer at the current moment (unit: m), P(t) is the furnace pressure at the current moment (unit: Pa), k1 is the proportionality coefficient between the fuel flow and the thickness of the material layer and the furnace pressure (unit: kg / m·Pa^α), and α1 is the influence index of the furnace pressure on the fuel flow.

[0055] The adjustment of the air flow mainly depends on the wind box temperature and the furnace pressure. The wind box temperature affects the fluidity of the air flow, and the furnace pressure affects the distribution of the air flow. The two together determine the supply amount of air. The calculation formula for the air flow can be expressed as:

[0056]

[0057] In Equation (5), u2(t) is the air flow at time t (unit: Nm 3 / s or kg / s), T(t) is the wind box temperature at the current moment (unit: °C or K), P(t) is the furnace pressure at the current moment (unit: Pa), k2 is the proportionality coefficient between the air flow and the wind box temperature and the furnace pressure (unit: kg / m·Pa^α), and α2 is the influence index of the furnace pressure on the air flow.

[0058] The adjustment of the air volume is mainly carried out according to the gas flow situation. The gas flow situation is comprehensively affected by the furnace pressure, the wind box temperature, and the fuel flow. In order to avoid gas flow waste or uneven combustion, it is necessary to dynamically adjust the air volume according to the real-time monitored air flow distribution. The calculation formula for the air volume can be expressed as:

[0059]

[0060] In Equation (6), u3(t) is the air volume at time t (unit: Nm 3 / s or kg / s), P(t) is the furnace pressure at the current moment (unit: Pa), Tavg (t) is the average value of the bellow temperature at the current moment (unit: °C or K), T set is the set target value of the bellow temperature (unit: °C or K), k3 is the proportionality coefficient between the air volume, furnace pressure and temperature difference (unit: Nm 3 / s·Pa·°C^α), α3 is the influence index of the temperature difference on the air volume, which is usually determined by experiments.

[0061] By continuously monitoring the control inputs of fuel flow, air flow and air volume, and combining the above calculation formulas, the control parameters in the ignition process of the sintering machine are continuously optimized. Through this adaptive control method, the system can maintain the stability of the ignition process, improve energy efficiency and reduce emissions, so as to achieve an efficient and environmentally friendly sintering production process.

[0062] The present invention can achieve precise control of the ignition process of the metallurgical sintering machine. The combination of the adaptive control algorithm and real-time data effectively optimizes various indexes such as ignition efficiency, energy consumption and emissions in the sintering process. Through continuous feedback regulation and abnormal warning, the system ensures the stability of the sintering process, improves production efficiency, and realizes an intelligent and automated sintering production process.

[0063] The following further elaborates on the above and other technical features and advantages of the present invention with reference to the accompanying drawings.

[0064] Embodiment 1

[0065] As Figure 1 shown, in this embodiment, an adaptive control method for the ignition process of a metallurgical sintering machine of the present invention is used for intelligent control of sintering ignition, and its main steps are as follows:

[0066] (1) Collect data on the ignition process of the sintering machine

[0067] The system collects data such as the thickness of the material layer, furnace pressure, speed of the sintering machine and the temperatures of multiple bellows in the sintering machine through sensors, transmits the collected data to the PLC, and then based on the OPC technology, establishes communication between the PC and the PLC, and transmits the obtained real-time data to the PC. At this stage, the system also preprocesses the data, such as noise filtering and data correction, to ensure the accuracy of the data.

[0068] (2) Real-time data display and calculation of control inputs

[0069] In the control system, the supply amount of fuel is adjusted according to the thickness of the material layer and the furnace pressure, the supply of air flow is adjusted according to the bellow temperature and the furnace pressure, and the air volume is adjusted according to the gas flow state and the bellow temperature. All calculation results are displayed on the PC side in real time to ensure accurate control of the ignition process. As Figure 2As shown, the opening degrees of the gas valve and the air valve during the ignition process of the sintering machine are presented through real-time change curves. The change trends and calculation results of each control input can be viewed in real time, providing accurate operation basis for operators.

[0070] (3) Ignition control and data recording

[0071] During the sintering process, all data will be stored in the background database, and the staff can view the historical data at any time. By querying the historical data, the change trends of the material layer thickness, furnace pressure, wind box temperature, fuel flow rate, and air flow rate can be viewed. Query the change trends of the material layer thickness, furnace pressure, wind box temperature, gas flow rate, and air flow rate for a certain period of time as Figures 3 to 7 shown.

[0072] (4) Abnormal warning and operation suggestions

[0073] The system uses sequence anomaly technology to mine anomaly data algorithms for real-time monitoring. Once abnormal fluctuations are detected in parameters such as fuel flow rate, air flow rate, or air volume, the system will automatically issue a warning. For example, when the fuel flow rate exceeds the set range or the wind box temperature is too high, the system will automatically adjust the control strategy and give operation suggestions. Combining the comparison of real-time data display and historical data, the system will provide targeted adjustment measures to ensure the stability and efficiency of the ignition process of the sintering machine. As Figure 8 shown is the warning content and suggested operation for the monitored sintering ignition situation for a certain period of time.

[0074] The above are only the preferred embodiments of the present invention, which are illustrative rather than restrictive to the present invention. Those skilled in the art understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present invention, but all will fall within the protection scope of the present invention.

Claims

1. An adaptive control method for the ignition process of a metallurgical sintering machine, characterized in that, It includes the following steps: S1, Collect ignition system data and sintering process parameters; S2, Conduct preliminary preprocessing on the parameter data collected in step S1 at the control terminal, establish a mathematical model for the sintering ignition process, and continuously optimize various control parameters in the sintering machine ignition process in combination with the real-time collected data; S3, If the ignition parameters do not meet the optimization requirements, adjust the ignition parameters, give corresponding level warnings, generate optimization suggestions, and output process adjustment suggestions; if the ignition parameters meet the optimization requirements, record and maintain the current ignition state, and output the ignition efficiency.

2. The adaptive control method for the ignition process of a metallurgical sintering machine according to claim 1, characterized in that, In the said step S1, the key parameters include the material layer thickness, furnace pressure, sintering machine speed, and wind box temperature. The material layer thickness is used to control the distribution of fuel and the stability of ignition. The furnace pressure is used to reflect the air flow distribution during the ignition process. The sintering machine speed is used to monitor the speed of the sintering machine in real time to ensure the residence time of the material layer and the uniformity of ignition. The wind box temperature is used to analyze the mixing state of the air flow and the fuel.

3. The adaptive control method for the ignition process of a metallurgical sintering machine according to claim 1, characterized in that, In the said step S2, the preliminary preprocessing includes noise filtering and data correction to ensure data accuracy.

4. The adaptive control method for the ignition process of a metallurgical sintering machine according to claim 1, characterized in that, In the said step S2, the mathematical model of the sintering ignition process is as follows: y(t) = Cx(t) + Du(t) Where, x(t) is the system state vector, u(t) is the control input, including fuel flow rate, air flow rate, and air volume, y(t) is the output, including ignition intensity and fuel efficiency, and A, B, C, D are the state matrix, input matrix, output matrix, and transfer matrix of the system respectively.

5. The adaptive control method for the ignition process of a metallurgical sintering machine according to claim 4, characterized in that, The said control input u(t) is optimized through the following objective function: where y target (k) is a predetermined target output, λ is a regularization parameter used to balance the magnitude of the control input and the error of the target output, and N is the prediction step; the optimization objective is to make the output parameters during the ignition process as close as possible to the target values while keeping the control input within the allowable range.

6. The adaptive control method for the ignition process of a metallurgical sintering machine according to claim 4, wherein, The calculation formula of the said fuel flow rate is as follows: Where, u1(t) is the fuel flow rate at time t, L(t) is the material layer thickness at the current moment, P(t) is the furnace pressure at the current moment, k1 is the proportionality coefficient between the fuel flow rate and the material layer thickness and furnace pressure, and α1 is the influence index of the furnace pressure on the fuel flow rate.

7. The adaptive control method for the ignition process of a metallurgical sintering machine according to claim 4, characterized in that, The calculation formula of the said air flow rate is as follows: Where, u2(t) is the air flow rate at time t, T(t) is the wind box temperature at the current moment, P(t) is the furnace pressure at the current moment, k2 is the proportionality coefficient between the air flow rate and the wind box temperature and furnace pressure, and α2 is the influence index of the furnace pressure on the air flow rate.

8. The adaptive control method for the ignition process of a metallurgical sintering machine according to claim 4, characterized in that, The calculation formula of the said air volume is as follows: Among them, u3(t) is the air volume at time t, P(t) is the furnace pressure at the current moment, T avg (t) is the average value of the air box temperature at the current moment, T set is the set target value of the air box temperature, k3 is the proportionality coefficient between the air volume, furnace pressure and temperature difference, and α3 is the influence index of the temperature difference on the air volume.

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