Optimized control method and system for combustible gas recovery

Abstract

The present application belongs to the field of smelting coal gas recovery, and particularly relates to an optimized control method and system for combustible gas recovery. The method divides the smelting process into N measurement time periods, and calculates the average secondary combustion coefficient of each time period in real time. Meanwhile, M target smelting time zones and their weights are set, and a dynamic target value sequence is established. Based on the initial fan speed, the measured coefficient is adjusted through multiple iterations of the furnace, and when the measured coefficient is greater than the target value, the speed is reduced in steps, and a thermal imager and a differential pressure instrument are introduced to monitor the smoke emission. A smoke emission rate statistics and tolerance threshold judgment mechanism is established to trigger speed backtracking adjustment, and finally the average secondary combustion coefficient of each time period is minimized to generate an optimal fan speed model. The present application maximizes the improvement of the calorific value of coal gas and the recovery of carbon monoxide under the premise of preventing smoke from the furnace mouth.

Description

Technical Field

[0001] This invention belongs to the field of metallurgical gas recovery, and particularly relates to an optimized control method and system for combustible gas recovery. Background Technology

[0002] In the converter gas recovery process, there is always a core technical contradiction: in order to recover high-concentration, high-calorific-value carbon monoxide gas, it is necessary to use the traction force generated by the blower to stabilize the differential pressure at the furnace mouth within a slightly positive pressure range, so as to effectively prevent air intake and avoid the precious CO from coming into contact with oxygen and undergoing secondary combustion, and being oxidized into low-calorific-value carbon dioxide. However, current control strategies mostly rely on fixed or only a few preset fan speed modes. This extensive control method, unable to respond in real time to the rapidly changing gas production conditions during smelting, leads to a double dilemma: on the one hand, during most periods, the fan suction is often excessive, which, while preventing smoke, results in the intake of excessive air, causing avoidable CO secondary combustion losses and significantly reducing the calorific value of the gas; on the other hand, in certain smelting stages, insufficient suction may cause flue gas to overflow from the furnace mouth, posing serious safety and environmental hazards. This one-size-fits-all control mode makes it impossible to achieve an optimal balance between the two key objectives of safe, smokeless operation and maximizing calorific value in gas recovery, resulting in considerable economic losses. Therefore, it is necessary to develop a method that can dynamically and precisely control the fan speed to maximize the suppression of secondary combustion and increase the calorific value of gas recovery while ensuring absolute safety in production.

[0003] The existing technologies have the following problems: the existing technologies only consider the fan speed setting from a single point steady-state condition, or perform segmented control based on a rough time period, but cannot accurately balance the amount of air drawn into the furnace and the flue gas extraction force according to the actual dynamics of gas generation in the smelting process, so as to achieve the dual goals of safe explosion suppression and calorific value improvement; therefore, the present invention provides an optimized control method and system for combustible gas recovery. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes an optimized control method and system for combustible gas recovery. This method divides the smelting process into N measurement time periods and calculates the average secondary combustion coefficient for each time period in real time. Simultaneously, it sets M target smelting time zones and their weights to establish a dynamic target value sequence. Based on the initial fan speed, it adjusts the speed through multiple furnace iterations, gradually reducing the speed when the measured coefficient exceeds the target value, and introduces a thermal imager and a differential pressure gauge to monitor flue gas escape. A smoke occurrence rate statistics and tolerance threshold judgment mechanism are established to trigger speed backtracking adjustment. Ultimately, under safety constraints, the average secondary combustion coefficient for each time period is minimized, generating an optimal fan speed model. This invention maximizes the calorific value of the gas and the amount of carbon monoxide recovered while preventing smoke from the furnace opening.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] Optimized control methods for combustible gas recovery include:

[0007] Set N measurement time periods and calculate the real-time interval average secondary combustion coefficient sequence within the N measurement time periods during the smelting process;

[0008] Simultaneously, M target smelting time zones are set within the same smelting process, and secondary combustion target values ​​are defined to obtain a sequence of secondary combustion target values ​​for each target smelting time zone. ;

[0009] Set an initial fan speed and smoke occurrence rate tolerance value, respond to the initial fan speed, and determine the correspondence between the real-time interval average secondary combustion coefficient sequence and the M target smelting time zones based on the measurement time period corresponding to the measured real-time interval average secondary combustion coefficient sequence and the timestamp relationship between the target smelting time zones.

[0010] Based on the correspondence between the real-time interval average secondary combustion coefficient sequence and the M target smelting time zones, if the real-time interval average secondary combustion coefficient of any measurement time period within the N measurement time periods is greater than the secondary combustion target value of the corresponding target smelting time zone, then according to the preset iteration furnace, under the condition of the smoke occurrence rate tolerance value, with the secondary combustion target value as the target iteration direction and combined with the speed backtracking mechanism, the fan speed within the measurement time period under each iteration furnace is adjusted by a preset step length until the interval average secondary combustion coefficient of the measurement time period reaches the minimum or the deviation from the target value corresponding to the M target smelting time zones meets the preset deviation threshold.

[0011] Specifically, optimized control methods also include:

[0012] Repeat the iterative furnace process of the interval average secondary combustion coefficient corresponding to the measurement time period, and perform the same furnace iteration for the real-time interval average secondary combustion coefficient of all measurement time periods, so that while meeting the smoke occurrence rate tolerance value, the real-time interval average secondary combustion coefficient of all measurement time periods within N measurement time periods reaches the minimum or the deviation from the target value corresponding to the M target smelting time partitions meets the preset deviation threshold. Combined with the combustion coefficient-fan speed mapping table, obtain the fan speed parameters under the condition that the real-time interval average secondary combustion coefficient within N measurement time periods meets the condition, and encapsulate it into a fan speed model; representing the nth measurement time period in the smelting process corresponding to the bth iteration furnace.

[0013] Specifically, the process of obtaining the real-time interval-averaged secondary combustion coefficient sequence includes:

[0014] Based on the set N measurement time periods, the overall time length corresponding to the smelting process of each iteration furnace is divided into partitions to obtain the measurement time period sequence;

[0015] By installing carbon monoxide and carbon dioxide analyzers in the flue of the converter, the concentrations of carbon monoxide and carbon dioxide in each measurement time period of the measurement time period sequence are measured to obtain the measurement results for each measurement time period.

[0016] Based on the measurement results of each measurement time period in each iteration, the corresponding measurement time period for each iteration is calculated. Real-time interval average secondary combustion coefficient.

[0017] Specifically, the fan speed is adjusted by a preset step length during the measurement time period for each iteration of the furnace, including:

[0018] When at least one of the N measurement time periods in the current iteration furnace exists... If the real-time interval average secondary combustion coefficient is greater than the secondary combustion target value of the corresponding target smelting time zone, and there is no flue gas overflow from the converter during the current measurement period as detected by the configured thermal imager, differential pressure instrument, or manual observation, then the next furnace in the same measurement period... The following step is to subtract the preset step speed reduction length from the fan speed corresponding to the current iteration furnace and use this as the same measurement time period for the next iteration furnace. The first fan speed is used to operate the fan;

[0019] During the fan operation corresponding to the first fan speed response, the measurement time period is synchronously measured within the corresponding iterative furnace cycle. The real-time interval average secondary combustion coefficient and flue gas overflow measurement results are used, and the fan speed adjustment of the remaining iteration furnace is repeated until the preset iteration furnace B or the interval average secondary combustion coefficient is minimized or the deviation from the target value corresponding to the M target smelting time zones meets the preset deviation threshold.

[0020] Specifically, adjusting the fan speed by a preset step length during the measurement time period in each iteration of the furnace also includes:

[0021] When at least one of the N measurement time periods in the current iteration furnace exists... If the real-time interval average secondary combustion coefficient is greater than the secondary combustion target value of the corresponding target smelting time zone, and flue gas overflow is detected during the current measurement period by the configured thermal imager, differential pressure instrument, or manual observation, then in the same measurement period of the next iteration furnace... Next, the fan speed corresponding to the current iteration furnace is used as the second fan speed for the same measurement time period of the remaining iteration furnaces, that is, the preset step speed reduction length is set to 0, and the fan operation is performed.

[0022] Simultaneously, while performing the remaining iterations of the furnace under the second fan speed, measurements are simultaneously taken for each identical measurement time period under all iterations of the furnace. The real-time interval average secondary combustion coefficient and flue gas overflow measurement results are used until the preset iterative furnace number or the interval average secondary combustion coefficient is minimized or the deviation from the target value corresponding to the M target smelting time partitions meets the preset deviation threshold.

[0023] Specifically, adjusting the fan speed by a preset step length during the measurement time period in each iteration of the furnace also includes:

[0024] Statistics on the total number of actual iterative furnace runs within the same measurement time period The actual number of overflow iterations C corresponding to the flue gas overflow is used to calculate the measurement time period based on the ratio of the actual number of overflow iterations C to the total number of actual furnace iterations. Smoke incidence rate ;

[0025] when If the smoke occurrence rate is less than the preset tolerance value D, then the fan speed corresponding to the current iteration furnace is determined to be the upper limit of the smoke occurrence speed, and the current speed is used as the measurement time period. The corresponding local optimal speed, and the real-time combustion coefficient corresponding to the current local optimal speed is the measurement time period. The corresponding local optimal interval average secondary combustion coefficient.

[0026] Specifically, adjusting the fan speed by a preset step length during the measurement time period in each iteration of the furnace also includes:

[0027] when When the smoke occurrence rate tolerance value D is greater than or equal to the preset value, the corresponding fan speed of the current iteration furnace is determined to be less than the upper limit of the smoke occurrence speed. In this case, the preset speed backtracking mechanism is triggered until the measurement period ends. corresponding The smoke rate is reduced to a preset tolerance value D. At the same time, the fan speed corresponding to the current smoke rate tolerance value D is taken as the local backtracking optimal speed for the measurement period. The interval average secondary combustion coefficient corresponding to the local backtracking optimal speed is taken as the local optimal interval average secondary combustion coefficient for the measurement period.

[0028] The search process for the local optimal speed and the local optimal interval average secondary combustion coefficient corresponding to the repeated measurement time period involves synchronously searching for the local optimal speed and the local optimal interval average secondary combustion coefficient for N measurement time periods, and obtaining the sequence of local optimal speed and local optimal interval average secondary combustion coefficient corresponding to each measurement time period.

[0029] Specifically, the speed backtracking mechanism includes:

[0030] Get The fan speed corresponding to the smoke occurrence rate tolerance value D being greater than or equal to the preset value is used as the measurement time period. The search starting value is calculated by multiplying the preset step deceleration length by the value corresponding to the smoke occurrence rate tolerance value. For measurement time period The first initial rotational speed backtracking step value;

[0031] The measurement time period is obtained by adding the initial search value to the first initial rotational speed backtracking step value. The first backward fan speed value, and responding to the first backward fan speed value, repeats the measurement for at least one time period in the current iteration furnace. The corresponding real-time interval average secondary combustion coefficient is greater than the secondary combustion target value of the corresponding target smelting time zone, and the current measurement time period is detected by the configured thermal imager or differential pressure instrument. During the iterative furnace process corresponding to the overflow of flue gas, it is determined that the corresponding value is at the first retraction fan speed. If the smoke incidence rate is less than the preset tolerance value D, then the first back fan speed and the corresponding real-time combustion coefficient will be used as the measurement time period. The local optimal speed and the average secondary combustion coefficient of the local optimal range.

[0032] Specifically, the speed retrospective mechanism also includes:

[0033] If the smoke occurrence rate tolerance value D is greater than or equal to the first back fan speed value, then the search start value is the first back fan speed value, and the backtracking step value is the first starting speed value multiplied by the first back fan speed value. Add the first backward fan speed value to obtain the second backward fan speed value, and repeat the iteration and judgment process corresponding to the first backward fan speed value. If the corresponding... If the value is still greater than or equal to the smoke incidence rate tolerance value D, then repeat the acquisition, iteration, and judgment process corresponding to the second backward fan speed value to perform backtracking iteration of fan speed until the smoke incidence rate tolerance value D is met for the first time. Record the current backtracking number, the real-time fan speed value corresponding to meeting the smoke incidence rate tolerance value D, and the real-time interval average secondary combustion coefficient as the measurement time period. The corresponding local optimal interval average secondary combustion coefficient.

[0034] Specifically, the process of detecting flue gas overflow during the current measurement period through a configured thermal imager, differential pressure instrument, or manual observation includes:

[0035] The configured thermal imager is used to acquire infrared thermal imaging temperature field distribution or flue gas overflow data in the converter mouth area, and / or the differential pressure in the converter mouth area is acquired simultaneously through a differential pressure instrument.

[0036] Based on the temperature field distribution data or flue gas overflow data and differential pressure, when an abnormal flue gas plume is detected and the differential pressure is greater than the preset differential pressure threshold, it is determined that flue gas has escaped from the converter furnace mouth.

[0037] An optimized control system for combustible gas recovery includes: a first zone module, a second zone module, a mapping module, a speed adjustment module, and a global optimization module;

[0038] The first partitioning module is used to set N measurement time periods and calculate the real-time interval average secondary combustion coefficient sequence within the N measurement time periods during the smelting process;

[0039] The second partitioning module is used to simultaneously set M target smelting time partitions in the same smelting process, set secondary combustion target values, and obtain a sequence of secondary combustion target values ​​for each target smelting time partition, wherein... ;

[0040] The mapping module is used to set the initial fan speed and smoke occurrence rate tolerance value, respond to the initial fan speed, and determine the correspondence between the real-time interval average secondary combustion coefficient sequence and the M target smelting time partitions based on the measurement time period corresponding to the measured real-time interval average secondary combustion coefficient sequence and the timestamp relationship between the target smelting time partitions.

[0041] The speed adjustment module is used to adjust the fan speed within the measurement time period in each iteration according to the real-time interval average secondary combustion coefficient sequence and the corresponding relationship between the M target smelting time zones. If the real-time interval average secondary combustion coefficient of any measurement time period within the N measurement time periods is greater than the secondary combustion target value of the corresponding target smelting time zone, then, under the condition of the smoke occurrence rate tolerance value, the fan speed within the measurement time period in each iteration furnace is adjusted by a preset step length, with the secondary combustion target value as the target iteration direction and combined with the speed backtracking mechanism, until the interval average secondary combustion coefficient of the measurement time period reaches the minimum or the deviation from the target value corresponding to the M target smelting time zones meets the preset deviation threshold.

[0042] The global optimization module is used to repeat the measurement time period. The iterative furnace process for the corresponding interval-averaged secondary combustion coefficient, for all measurement time periods. The real-time interval average secondary combustion coefficient is iterated in the same furnace cycle, so that while meeting the smoke occurrence rate tolerance value, the real-time interval average secondary combustion coefficient of all measurement time periods in N measurement time periods reaches the minimum or the deviation from the target value corresponding to the M target smelting time partitions meets the preset deviation threshold. Combined with the combustion coefficient-fan speed mapping table, the fan speed parameters under the condition that the real-time interval average secondary combustion coefficient in N measurement time periods is met are obtained and encapsulated into a fan speed model. This represents the nth measurement time period in the smelting process corresponding to the bth iteration furnace.

[0043] Compared with the prior art, the beneficial effects of the present invention are:

[0044] This invention addresses the shortcomings of existing technologies by dividing the smelting process into N measurement time periods and M target smelting time partitions. It establishes a real-time correspondence between the interval-averaged secondary combustion coefficient sequence and the dynamic target value sequence, achieving refined partitioned control of the entire smelting process. A multi-iteration furnace optimization mechanism is employed, implementing step-by-step speed reduction adjustments when the measured coefficient exceeds the target value. Combined with dual monitoring of flue gas escape status using thermal imagers and differential pressure gauges, an intelligent judgment system based on smoke occurrence statistics and tolerance thresholds is constructed. A speed backtracking mechanism dynamically corrects the fan speed, globally minimizing the interval-averaged secondary combustion coefficient for each time period and generating an optimal fan speed model. This method significantly improves the carbon monoxide recovery concentration and calorific value in the gas, achieving synergistic optimization of converter gas recovery efficiency and safety. Attached Figure Description

[0045] Figure 1 This is a flowchart of the optimized control method for combustible gas recovery according to Embodiment 1 of the present invention;

[0046] Figure 2 This is a schematic diagram of the iterative furnace cycles for N measurement time periods in Embodiment 1 of the present invention;

[0047] Figure 3 This is a schematic diagram showing the relationship between the measurement time period and the target smelting time zone in Embodiment 1 of the present invention;

[0048] Figure 4 This is a block diagram of the optimized control system for combustible gas recovery in Embodiment 2 of the present invention. Detailed Implementation

[0049] Example 1

[0050] Please see Figure 1 The present invention provides an embodiment of an optimized control method for combustible gas recovery, comprising the following steps:

[0051] S1. Set N measurement time periods and calculate the N measurement time periods during the smelting process. Real-time interval-averaged secondary combustion coefficient sequence ;in, This represents the real-time interval average secondary combustion coefficient corresponding to the nth measurement time period in the smelting process corresponding to the b-th iteration furnace; B represents the preset iteration furnace, and N represents the total number of measurement time periods; This represents the nth measurement time period in the smelting process corresponding to the bth iteration furnace.

[0052] It should be further explained that the process of obtaining the real-time interval average secondary combustion coefficient sequence in this embodiment includes:

[0053] S101. Based on the set N measurement time periods, the overall time length corresponding to the smelting process of each iteration furnace is divided into partitions to obtain a sequence of measurement time periods. Further explanation is needed; please refer to [link / reference]. Figure 2 , The measurement time period sequence corresponds to the first iteration furnace batch. The second to Bth iteration furnace batches are the same as the first iteration furnace batch, which will not be repeated here; The real-time interval average secondary combustion coefficient corresponds to the B iterative furnace cycles in the nth measurement time period. It should be further noted that one iterative furnace cycle in this embodiment represents a complete smelting process. Furthermore, to achieve precise matching between the measurement time period and the actual smelting dynamics, and to overcome the poor adaptability of fixed time divisions to fluctuations in operating conditions, this embodiment generates adaptive measurement time periods based on data-driven principles. Specifically, by analyzing the variation characteristics of the interval average secondary combustion coefficient in historical furnace cycles, time periods with similar reaction characteristics are automatically identified, thereby establishing dynamic, rather than fixed, partition boundaries. Specifically, the system first collects historical flue gas concentration data and calculates the instantaneous change rate of the interval average secondary combustion coefficient to accurately capture the dynamic characteristics of the smelting process. Subsequently, a sliding window variance analysis is performed on the change rate curve to identify areas of drastic dynamic changes, supplemented by peak detection to locate key turning points. These points together constitute the basis for preliminary segmentation, ensuring that the partition boundaries are set at moments when operating conditions change significantly. Finally, all initial time periods are clustered based on curve shape and average rate of change, so that each measurement time period represents a stable and repeatable reaction state. In practical applications, by matching the real-time data with the typical partition patterns obtained from these clusters and allowing a floating threshold to be set for the time boundary, the partitions can be flexibly adapted to the actual reaction process of each furnace.

[0054] S102. By installing carbon monoxide and carbon dioxide analyzers in the converter flue, the carbon monoxide concentration in each measurement time period of the measurement time period sequence is measured. and carbon dioxide concentration Measurements were performed to obtain the results for each measurement time period; among which... The carbon monoxide concentration measured during the nth measurement time period in the smelting process corresponding to the bth iteration furnace; The carbon dioxide concentration measured during the nth measurement time period in the smelting process corresponding to the bth iteration furnace;

[0055] S103. Based on the measurement results of each measurement time period in each iteration, calculate the corresponding measurement time period for each iteration. The real-time interval average secondary combustion coefficient is as follows: ;

[0056] S2. Simultaneously, set M target smelting time partitions in the same smelting process. Set the secondary combustion target value Y, and obtain the secondary combustion target value sequence for each target smelting time zone, where... ; This represents the m-th target smelting time partition in the smelting process corresponding to the b-th iteration furnace. It should be further noted that the secondary combustion target value in this embodiment is not a strictly enforceable operational threshold for system operation, but rather an ideal directional benchmark for system optimization. The secondary combustion target value is set by those skilled in the art to a theoretically achievable low value, and is lower than the average level of traditional secondary combustion operations. This provides a clear optimization pull for the system. During the system's iterative optimization process, the absolute instruction is not to reach the secondary combustion target value, but rather to drive the average secondary combustion coefficient in the real-time interval to infinitely approach the secondary combustion target value as the optimization direction. When the real-time interval... When the inter-range average secondary combustion coefficient is significantly higher than the target value for secondary combustion, the system outputs a deceleration command to continuously explore the potential for reducing secondary combustion. When the system reaches the safety boundary, i.e., smoke appears at the furnace opening and the air supply pressure is greater than the gas holder pressure, making it impossible to further reduce the real-time inter-range average secondary combustion coefficient to the target value for secondary combustion, the system, through its built-in safety fault-tolerance mechanism, stops the downward search for the secondary combustion coefficient during this period and locks the actual optimal secondary combustion coefficient value under the current safety constraints. Simultaneously, to achieve a deep integration of the control strategy and the inherent laws of the smelting process, and to overcome the experience-dependent and subjective nature of manually setting target partitions and weights, an adaptive... The measurement time period is divided into segments, and a feature vector is constructed for each segment. The feature vector includes the arithmetic mean of the interval-averaged secondary combustion coefficient within the segment, the statistical variance of the interval-averaged secondary combustion coefficient within the segment, and the average induced draft fan speed corresponding to the segment. The feature vectors of all measurement segments within the same smelting cycle are combined into a sample set. An adaptive clustering algorithm is used to perform condition clustering analysis on this sample set. Each generated cluster is defined as a smelting condition stage with specific reaction characteristics. All measurement segments belonging to the same cluster are merged and connected according to their corresponding time order to form the target smelting time segment. Based on this, the calculation of each... The contribution index of the target smelting time zone to the global gas calorific value recovery is obtained by dividing the estimated carbon monoxide recovery in the target smelting time zone by the estimated theoretical total carbon monoxide production of the entire furnace. An initial weight value is assigned to each target smelting time zone according to the rule that the higher the contribution, the lower the weight value. In subsequent iterative optimization, a dynamic weight adjustment mechanism is established to monitor the deviation rate between the actual interval average secondary combustion coefficient and the dynamic target value in each target smelting time zone in real time. When the deviation rate of a target smelting time zone continuously exceeds a preset deviation rate threshold, the weight value of that target smelting time zone is reduced by a preset step size to strengthen the optimization.When the deviation change rate of a target smelting time zone remains below a preset deviation change rate threshold, the weight value of that target smelting time zone is increased by a preset step size to moderate the optimization intensity. Through this process, a closed-loop optimization of the target smelting time zone division and weight setting is achieved, ensuring that the control strategies at each stage of the smelting process conform to both process characteristics and global optimization requirements.

[0057] S3. Set the initial fan speed and smoke occurrence rate tolerance value, respond to the initial fan speed, and according to the measurement time period corresponding to the measured real-time interval average secondary combustion coefficient sequence. Zoned by target smelting time Based on the timestamp relationship, determine the correspondence between the real-time interval average secondary combustion coefficient sequence and the M target smelting time partitions. ; This indicates that the nth measurement time period in the smelting process corresponding to the bth iteration furnace is included in the mth target smelting time partition; please refer to [link / reference]. Figure 3 The corresponding display is in the same iteration batch b. The remaining variable labels in the diagram will not be elaborated here. It should be further explained that the process of obtaining the corresponding relationship in this embodiment includes: at the beginning of each iteration, the system establishes and updates the mapping relationship based on the time intervals of the currently dynamically divided measurement time periods and the target smelting time partitions through the following logical steps: First, define explicit time intervals for all measurement time periods and initialize an empty mapping table; then, for each measurement time period, calculate its overlap length with the time intervals of all target smelting time partitions, and filter out all overlapping target smelting time partitions as a candidate set; if there is a unique target with the maximum overlap in the candidate set... For smelting time partitions, a mapping relationship is directly established. If multiple target smelting time partitions have the same maximum overlap, the historical mapping target for that measurement time period in the previous batch is preferred. If the historical mapping target is not applicable, the target smelting time partition with the closest center point of the time interval is selected for matching. For measurement time periods that do not overlap with any target smelting time partitions, they are assigned to the target smelting time partition with the closest center point of the time interval. Finally, the system verifies and outputs the generated complete mapping table to ensure that each measurement time period is mapped to a unique target smelting time partition, thereby achieving stable and continuous updates of the mapping relationship under dynamic partitioning conditions.

[0058] S4. Based on the correspondence between the real-time interval average secondary combustion coefficient sequence and the M target smelting time zones, if the real-time interval average secondary combustion coefficient of any measurement time period within the N measurement time periods is greater than the secondary combustion target value of the corresponding target smelting time zone, then according to the preset iteration furnace, under the condition of the smoke occurrence rate tolerance value, with the secondary combustion target value as the target iteration direction and combined with the speed backtracking mechanism, the fan speed within the measurement time period under each iteration furnace is adjusted by a preset step length until the interval average secondary combustion coefficient of the measurement time period reaches the minimum or the deviation from the target value corresponding to the M target smelting time zones meets the preset deviation threshold. It should be further explained that in this embodiment, when adjusting the fan speed for each measurement time period with the secondary combustion target value as the iteration direction and a preset step length, a dynamic pressure constraint condition is introduced. This dynamic pressure constraint condition includes a correlation constraint between the converter furnace mouth micro-pressure difference and the gas holder pressure. Specifically, the implementation process is as follows: a furnace mouth micro-pressure difference ≤ 0 is set as the no-smoke constraint threshold. When a furnace mouth micro-pressure difference > 0 is detected, it is determined that flue gas overflows, and the speed reduction adjustment for that measurement time period is stopped. Simultaneously, a mapping relationship between fan speed and gas supply pressure is established. This mapping relationship means that the gas supply pressure increases with increasing fan speed, and as the amount of gas stored in the gas holder increases (i.e., the gas holder pressure increases), the fan speed needs to be increased accordingly to maintain the gas supply pressure. Based on this mapping relationship, the current pressure of the gas holder is collected in real time, and the required minimum pressure is dynamically calculated. The minimum fan speed is adjusted to meet the gas supply pressure requirements, ensuring that the fan speed adjustment during each measurement period is neither lower than the minimum fan speed to guarantee the gas supply pressure, nor lower than the fan speed that would cause a slight pressure difference at the furnace mouth > 0 to avoid smoke. Furthermore, the average secondary combustion coefficient for the corresponding interval is minimized at the corresponding time point. The pressure relationship between the gas supply pressure and the gas storage tank is maintained throughout the entire constraint process. In this embodiment, the gas supply pressure corresponding to the fan speed at any given time point must be greater than the gas storage tank pressure at the corresponding time point; otherwise, the recovered gas cannot be stored, leading to resource waste and reduced gas recovery efficiency. Through the above dynamic constraints, the fan speed is adapted between the gas supply pressure and the smoke-free condition. Finally, after iteration, a fan speed model that balances gas supply pressure requirements and secondary combustion optimization is obtained, improving the stability and efficiency of gas recovery.

[0059] It should be further noted that, in this embodiment, the following applies to each iteration furnace cycle. The internal fan speed is adjusted by a preset step length for speed reduction, including:

[0060] S401. When at least one of the N measurement time periods in the current iteration furnace exists... If the real-time interval average secondary combustion coefficient is greater than the secondary combustion target value of the corresponding target smelting time zone, and there is no flue gas overflow from the converter during the current measurement period as detected by the configured thermal imager, differential pressure instrument, or manual observation, then the next furnace in the same measurement period... The following step is to subtract the preset step speed reduction length from the fan speed corresponding to the current iteration furnace and use this as the same measurement time period for the next iteration furnace. The first fan speed is used to operate the fan. The preset step speed reduction length in this embodiment combines the pressure corresponding to the smoke occurrence rate and the pressure constraint conditions corresponding to the gas storage tank. Its core motivation is to resolve the dynamic contradiction between speed reduction optimization and system pressure safety, ensuring both a continuous reduction in the average secondary combustion coefficient within the interval and preventing smoke from the furnace opening or interruption of gas delivery due to speed adjustment. The specific implementation process includes: First, determining the benchmark step length according to a predetermined proportion of the induced draft fan's rated speed; Second, calculating the furnace opening pressure factor in the following way: When calculating the pressure constraint step speed reduction length, firstly, linearly normalizing the furnace opening differential pressure. Processing: The measured differential pressure value is linearly mapped between a preset safety threshold and a minimum allowable value. When the differential pressure approaches the safety threshold, a factor value close to zero is output; when the differential pressure approaches the minimum allowable value, a factor value close to one is output. Simultaneously, the delivery pressure is processed using a saturation function: the difference between the current delivery pressure and the dynamic minimum delivery pressure is calculated. When the difference is less than or equal to zero, 0 is output; when the difference is greater than or equal to the preset pressure margin, 1 is output. In between, the corresponding factor values ​​are output in a linear proportion. Finally, the product of the reference step length and the smaller of the above two factors is taken as the actual step speed reduction length. When either factor approaches zero, the speed reduction operation is automatically stopped.

[0061] It should be further noted that in this embodiment, the current measurement time period is detected by a configured thermal imager or differential pressure instrument. The process of smoke escaping from inside includes:

[0062] S4011. Using a configured thermal imager, acquire infrared thermal imaging temperature field distribution or flue gas overflow data of the converter mouth area, and / or simultaneously acquire differential pressure of the converter mouth area using a differential pressure instrument.

[0063] S4012. Based on the temperature field distribution data or flue gas overflow data and differential pressure, when an abnormal flue gas plume is detected and the differential pressure is greater than the preset differential pressure threshold, it is determined that flue gas has escaped from the converter furnace opening.

[0064] S402. Simultaneously, while responding to the second fan speed and performing the remaining iteration furnace runs, synchronously measure each identical measurement time period under all iteration furnace runs. The real-time interval average secondary combustion coefficient and flue gas overflow measurement results are used until the preset iterative furnace number or the interval average secondary combustion coefficient is minimized or the deviation from the target value corresponding to the M target smelting time partitions meets the preset deviation threshold.

[0065] S403, when at least one of the N measurement time periods in the current iteration furnace exists... If the real-time interval average secondary combustion coefficient is greater than the secondary combustion target value of the corresponding target smelting time zone, and flue gas overflow is detected during the current measurement period by the configured thermal imager, differential pressure instrument, or manual observation, then in the same measurement period of the next iteration furnace... Next, the fan speed corresponding to the current iteration furnace is used as the second fan speed for the same measurement time period of the remaining iteration furnaces, that is, the preset step speed reduction length is set to 0, and the fan operation is performed.

[0066] S404. Simultaneously, while responding to the second fan speed and performing the remaining iterations, synchronously measure each identical measurement time period under all iterations. The real-time interval average secondary combustion coefficient and flue gas overflow measurement results are used until the preset iterative furnace number or the interval average secondary combustion coefficient is minimized or the deviation from the target value corresponding to the M target smelting time partitions meets the preset deviation threshold.

[0067] S405. Statistically analyze the same measurement time period within the total number of actual iterative furnace cycles. The actual number of overflow iterations C corresponding to the flue gas overflow is used to calculate the measurement time period based on the ratio of the actual number of overflow iterations C to the total number of actual furnace iterations. Smoke incidence rate This embodiment uses the actual total number of iterations rather than a preset maximum number of iterations for calculation. Its core motivation is to achieve real-time, proactive perception and intervention of abnormal risks during production. In actual production, the frequency of flue gas overflow often reaches the risk threshold before the preset total number of iterations is reached. If the preset number is rigidly used as the denominator, it will severely dilute and delay the assessment of the true risk probability, leading to significant delays in regulatory measures. Calculations based on the actual number of iterations can dynamically and sensitively capture the instantaneous smoke trend in the current production state. Once the occurrence rate exceeds the safety threshold, an early warning or shutdown command can be immediately triggered, thereby achieving a shift from "post-event statistics" to "process interruption," effectively preventing continuous pollution and equipment damage.

[0068] S406, when If the smoke occurrence rate is less than the preset tolerance value D, then the fan speed corresponding to the current iteration furnace is determined to be the upper limit of the smoke occurrence speed, and the current speed is used as the measurement time period. The corresponding local optimal speed, and the real-time combustion coefficient corresponding to the current local optimal speed is the measurement time period. The corresponding local optimal interval average secondary combustion coefficient;

[0069] S407, when When the smoke occurrence rate tolerance value D is greater than or equal to the preset value, the corresponding fan speed for the current iteration furnace is determined to be less than the upper limit of the smoke occurrence speed. In this case, the preset speed backtracking mechanism is triggered until the measurement period ends. corresponding The smoke rate is reduced to a preset tolerance value D. At the same time, the fan speed corresponding to the current smoke rate tolerance value D is taken as the local backtracking optimal speed for the measurement period. The interval average secondary combustion coefficient corresponding to the local backtracking optimal speed is taken as the local optimal interval average secondary combustion coefficient for the measurement period.

[0070] S408. The search process for the local optimal speed and the local optimal interval average secondary combustion coefficient corresponding to the repeated measurement time period involves synchronously searching for the local optimal speed and the local optimal interval average secondary combustion coefficient for N measurement time periods to obtain the sequence of local optimal speed and local optimal interval average secondary combustion coefficient for each measurement time period.

[0071] It should be further explained that the rotational speed backtracking mechanism in this embodiment includes:

[0072] S4071, Obtain The fan speed corresponding to the smoke occurrence rate tolerance value D being greater than or equal to the preset value is used as the measurement time period. The search starting value is calculated by multiplying the preset step deceleration length by the value corresponding to the smoke occurrence rate tolerance value. For measurement time period The first initial speed backtracking step value; it should be further explained that in this embodiment, the initial speed backtracking step value adopts a dynamic calculation method linked to the real-time smoke occurrence rate. The design motivation is to establish a risk-aware adaptive adjustment mechanism: when a high smoke occurrence rate is detected, it indicates that the current speed has significantly deviated from the safety boundary. The system multiplies the baseline step speed reduction length by the real-time smoke occurrence rate to form a backtracking step value positively correlated with the risk level, thereby achieving rapid safe return under high-risk conditions and fine adjustment under low-risk conditions. This design enables the speed backtracking process to respond quickly to safety hazards, effectively preventing the continuous deterioration of the operating conditions, while avoiding excessive backtracking or slow convergence caused by fixed step sizes. Ultimately, under the premise of ensuring the safe and stable operation of the system, it significantly improves the convergence speed and control accuracy of the optimization process.

[0073] S4072. Using the search starting value plus the first starting speed backtracking step value, obtain the measurement time period. The first backward fan speed value, and responding to the first backward fan speed value, repeats the measurement for at least one time period in the current iteration furnace. The corresponding real-time interval average secondary combustion coefficient is greater than the secondary combustion target value of the corresponding target smelting time zone, and the current measurement time period is detected by the configured thermal imager or differential pressure instrument. During the iterative furnace process corresponding to the overflow of flue gas, it is determined that the corresponding value of the first retracting fan speed is... If the smoke incidence rate is less than the preset tolerance value D, then the first back fan speed and the corresponding real-time combustion coefficient will be used as the measurement time period. The local optimal speed and the average secondary combustion coefficient of the local optimal range;

[0074] S4073. If the smoke occurrence rate tolerance value D is greater than or equal to the first back fan speed value, then the search start value is the first back fan speed value, and the backtracking step value of the first start speed value is multiplied by the first back fan speed value. Add the first backward fan speed value to obtain the second backward fan speed value, and repeat the iteration and judgment process corresponding to the first backward fan speed value. If the corresponding... If the value is still greater than or equal to the smoke incidence rate tolerance value D, then repeat the acquisition, iteration, and judgment process corresponding to the second backward fan speed value to perform backtracking iteration of fan speed until the smoke incidence rate tolerance value D is met for the first time. Record the current backtracking number, the real-time fan speed value corresponding to meeting the smoke incidence rate tolerance value D, and the real-time interval average secondary combustion coefficient as the measurement time period. The corresponding local optimal interval average secondary combustion coefficient.

[0075] S5. Repeat the measurement time period. The iterative furnace process for the corresponding interval-averaged secondary combustion coefficient, for all measurement time periods. The real-time interval average secondary combustion coefficient is iterated in the same furnace cycle, so that while meeting the smoke occurrence rate tolerance value, the real-time interval average secondary combustion coefficient of all measurement time periods in N measurement time periods reaches the minimum or the deviation from the target value corresponding to the M target smelting time partitions meets the preset deviation threshold. Combined with the combustion coefficient-fan speed mapping table, the fan speed parameters under the condition that the real-time interval average secondary combustion coefficient in N measurement time periods is met are obtained and encapsulated into a fan speed model. This represents the nth measurement time period in the smelting process corresponding to the bth iteration furnace. The fan speed model is input into the configured smelting control system and verified in real time using a twin algorithm. Based on the data obtained from the verification, the fan speed model is fine-tuned online. It should be further explained that the real-time verification and online fine-tuning process of the fan speed model and the twin algorithm in this embodiment includes: First, constructing a digital twin model that completely corresponds to the physical converter, synchronously acquiring sensor data from the production site through a real-time data interface, and dynamically simulating the actual smelting process in virtual space; then, running the encapsulated fan speed model in parallel in the digital twin environment, while setting a traditional control strategy as a benchmark, and comparing the differences between the two in key indicators such as the interval average secondary combustion coefficient, flue gas escape probability, and gas calorific value in real time; when the deviation between the model output value and the actual operating conditions exceeds a set threshold within multiple consecutive smelting cycles, parameter fine-tuning is initiated, using an incremental learning algorithm with real-time data collected by the digital twin system as training samples to dynamically adjust the weight allocation of parameters in each partition of the speed model; finally, after multiple rounds of iterative verification to ensure that the model output and the digital twin system achieve stable convergence, the optimized parameter configuration is synchronized to the field control system, forming a closed-loop optimization system with self-learning capabilities. This method constructs a safe and reliable verification environment through digital twin technology, avoiding the risks of direct on-site debugging and realizing the continuous evolution of the control model.

[0076] This embodiment integrates four core technologies: dynamic partitioning mapping, pressure adaptive constraints, risk perception backtracking, and digital twin verification. It constructs a converter gas recovery optimization system that combines accuracy, safety, and self-evolution capabilities. In particular, by dynamically dividing the system into N measurement zones based on flue gas concentration change characteristics and generating M target zones based on operating condition clustering, the system overcomes the limitations of fixed-time partitioning, achieving precise matching between smelting reaction dynamics and control strategies. This design allows the optimization target to align with actual process fluctuations, laying the foundation for efficient control. Furthermore, by establishing a dual-constraint model of fan speed, furnace inlet micro-pressure difference, and conveying pressure, and employing linear normalization and saturation function algorithms to dynamically calculate the step reduction... In terms of speed reduction, the system simultaneously ensures smoke prevention at the furnace opening and stable gas delivery pressure during the speed reduction optimization process. This pressure adaptive mechanism fundamentally resolves the contradiction between efficiency and safety. By introducing a speed backtracking mechanism linked to the smoke occurrence rate, the system can intelligently adjust the backtracking step size according to the risk level. It quickly returns to the safe range during high-risk periods and maintains fine-tuning during low-risk periods. This risk perception capability significantly improves the convergence speed and control accuracy of the optimization process. Finally, through parallel verification and incremental learning fine-tuning in a digital twin environment, a closed loop for continuous model optimization is constructed, enabling the fan speed model to safely iterate in the virtual space and synchronize with the physical system, forming a self-improving intelligent control system. In summary, this solution achieves global minimization of the interval-average secondary combustion coefficient through multi-technology integration. While ensuring zero-smoke safety constraints and stable delivery, it maximizes the gas calorific value recovery efficiency to the process limit, while also possessing strong robustness to cope with operating condition fluctuations and long-term self-evolution capabilities.

[0077] Example 2

[0078] Please see Figure 4 Another embodiment of the present invention provides an optimized control system for combustible gas recovery, comprising: a first partition module, a second partition module, a mapping module, a speed adjustment module, and a global optimization module;

[0079] The first partition module is used to set N measurement time periods and calculate N measurement time periods during the smelting process. Real-time interval-averaged secondary combustion coefficient sequence ;in, This represents the real-time interval average secondary combustion coefficient corresponding to the nth measurement time period in the smelting process corresponding to the b-th iteration furnace; B represents the preset iteration furnace, and N represents the total number of measurement time periods; This represents the nth measurement time period in the smelting process corresponding to the bth iteration furnace;

[0080] The second partitioning module is used to simultaneously set M target smelting time partitions in the same smelting process. Set secondary combustion target values ​​and obtain the secondary combustion target value sequence for each target smelting time zone, where... ; This represents the m-th target smelting time partition in the smelting process corresponding to the b-th iteration furnace.

[0081] The mapping module is used to set the initial fan speed and smoke occurrence rate tolerance value, respond to the initial fan speed, and determine the measurement time period corresponding to the measured real-time interval average secondary combustion coefficient sequence. Zoned by target smelting time Based on the timestamp relationship, determine the correspondence between the real-time interval average secondary combustion coefficient sequence and the M target smelting time partitions. ; This indicates that the nth measurement time period in the smelting process corresponding to the bth iteration furnace is included in the mth target smelting time partition;

[0082] The speed adjustment module is used to adjust the fan speed within the measurement time period in each iteration according to the real-time interval average secondary combustion coefficient sequence and the corresponding relationship between the M target smelting time zones. If the real-time interval average secondary combustion coefficient of any measurement time period within the N measurement time periods is greater than the secondary combustion target value of the corresponding target smelting time zone, then, under the condition of the smoke occurrence rate tolerance value, the fan speed within the measurement time period in each iteration furnace is adjusted by a preset step length, with the secondary combustion target value as the target iteration direction and combined with the speed backtracking mechanism, until the interval average secondary combustion coefficient of the measurement time period reaches the minimum or the deviation from the target value corresponding to the M target smelting time zones meets the preset deviation threshold.

[0083] The global optimization module is used to repeat the measurement time period. The iterative furnace process for the corresponding interval-averaged secondary combustion coefficient, for all measurement time periods. The real-time interval average secondary combustion coefficient is iterated in the same furnace cycle, so that while meeting the smoke occurrence rate tolerance value, the real-time interval average secondary combustion coefficient of all measurement time periods in N measurement time periods reaches the minimum or the deviation from the target value corresponding to the M target smelting time partitions meets the preset deviation threshold. Combined with the combustion coefficient-fan speed mapping table, the fan speed parameters under the condition that the real-time interval average secondary combustion coefficient in N measurement time periods is met are obtained and encapsulated into a fan speed model. This represents the nth measurement time period in the smelting process corresponding to the bth iteration furnace. The fan speed model is input into the configured smelting control system and verified in real time using a twin algorithm. Based on the data obtained from the verification, the fan speed model is fine-tuned online.

[0084] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments under the guidance of the present invention without departing from the spirit and scope of the present invention. All of these variations are within the protection scope of the present invention.

Claims

1. An optimized control method for combustible gas recovery, characterized in that, include: Set N measurement time periods and calculate the real-time interval average secondary combustion coefficient sequence within the N measurement time periods during the smelting process; Simultaneously, M target smelting time zones are set within the same smelting process, and secondary combustion target values ​​are defined to obtain a sequence of secondary combustion target values ​​for each target smelting time zone. ; Set an initial fan speed and smoke occurrence rate tolerance value, respond to the initial fan speed, and determine the correspondence between the real-time interval average secondary combustion coefficient sequence and the M target smelting time zones based on the measurement time period corresponding to the measured real-time interval average secondary combustion coefficient sequence and the timestamp relationship between the target smelting time zones. Based on the correspondence between the real-time interval average secondary combustion coefficient sequence and the M target smelting time zones, if the real-time interval average secondary combustion coefficient of any measurement time period within the N measurement time periods is greater than the secondary combustion target value of the corresponding target smelting time zone, then according to the preset iteration furnace, under the condition of the smoke occurrence rate tolerance value, with the secondary combustion target value as the target iteration direction and combined with the speed backtracking mechanism, the fan speed within the measurement time period under each iteration furnace is adjusted by a preset step length until the interval average secondary combustion coefficient of the measurement time period reaches the minimum or the deviation from the target value corresponding to the M target smelting time zones meets the preset deviation threshold. The speed reduction adjustment introduces a pressure constraint condition constructed by the converter mouth micro-pressure difference and the gas storage tank pressure. Specifically, the furnace mouth micro-pressure difference ≤ 0 is set as the no-smoke constraint threshold. When the furnace mouth micro-pressure difference > 0 is detected, it is determined that the flue gas overflows and the speed reduction adjustment for that measurement period is stopped. A mapping relationship between the fan speed and the gas supply pressure is established, and the current pressure of the gas storage tank is collected in real time. Based on the mapping relationship between the fan speed and the gas supply pressure, the minimum fan speed that meets the gas supply pressure requirement is calculated. The lower limit of the fan speed adjustment is defined as the larger value between the minimum fan speed and the critical fan speed that avoids the furnace mouth micro-pressure difference > 0. This ensures that the gas supply pressure corresponding to the fan speed at any time point is always greater than the current pressure of the gas storage tank, and minimizes the interval average secondary combustion coefficient of the corresponding measurement period. The speed backtracking mechanism includes: Obtain the smoke occurrence rate The fan speed corresponding to the smoke occurrence rate tolerance value D being greater than or equal to the preset value is used as the measurement time period. The search starting value is calculated by multiplying the preset step deceleration length by the value corresponding to the smoke occurrence rate tolerance value. For measurement time period The first initial rotational speed backtracking step value; The measurement time period is obtained by adding the initial search value to the first initial rotational speed backtracking step value. The first backward fan speed value, and responding to the first backward fan speed value, repeats the measurement for at least one time period in the current iteration furnace. The corresponding real-time interval average secondary combustion coefficient is greater than the secondary combustion target value of the corresponding target smelting time zone, and the current measurement time period is detected by the configured thermal imager or differential pressure instrument. During the iterative furnace process corresponding to the overflow of flue gas, it is determined that the corresponding value of the first retracting fan speed is... If the smoke incidence rate is less than the preset tolerance value D, then the first back fan speed and the corresponding real-time combustion coefficient will be used as the measurement time period. The local optimal speed and the average secondary combustion coefficient of the local optimal range; If the smoke occurrence rate tolerance value D is greater than or equal to the first back fan speed value, then the search start value is the first back fan speed value, and the backtracking step value is the first starting speed value multiplied by the first back fan speed value. Add the first backward fan speed value to obtain the second backward fan speed value, and repeat the iteration and judgment process corresponding to the first backward fan speed value. If the corresponding... If the value is still greater than or equal to the smoke incidence rate tolerance value D, then repeat the acquisition, iteration, and judgment process corresponding to the second backward fan speed value to perform backtracking iteration of fan speed until the smoke incidence rate tolerance value D is met for the first time. Record the current backtracking number, the real-time fan speed value corresponding to meeting the smoke incidence rate tolerance value D, and the real-time interval average secondary combustion coefficient as the measurement time period. The corresponding local optimal interval average secondary combustion coefficient.

2. The optimized control method for combustible gas recovery as described in claim 1, characterized in that, The optimized control method further includes: Repeat the measurement time period The iterative furnace process for the corresponding interval-averaged secondary combustion coefficient, for all measurement time periods. The real-time interval average secondary combustion coefficient is iterated in the same furnace cycle, so that while meeting the smoke occurrence rate tolerance value, the real-time interval average secondary combustion coefficient of all measurement time periods in N measurement time periods reaches the minimum or the deviation from the target value corresponding to the M target smelting time partitions meets the preset deviation threshold. Combined with the combustion coefficient-fan speed mapping table, the fan speed parameters under the condition that the real-time interval average secondary combustion coefficient in N measurement time periods is met are obtained and encapsulated into a fan speed model. This represents the nth measurement time period in the smelting process corresponding to the bth iteration furnace.

3. The optimized control method for combustible gas recovery as described in claim 2, characterized in that, The process of obtaining the real-time interval-averaged secondary combustion coefficient sequence includes: Based on the set N measurement time periods, the overall time length corresponding to the smelting process of each iteration furnace is divided into partitions to obtain the measurement time period sequence; By installing carbon monoxide and carbon dioxide analyzers in the flue of the converter, the concentrations of carbon monoxide and carbon dioxide in each measurement time period of the measurement time period sequence are measured to obtain the measurement results for each measurement time period. Based on the measurement results of each measurement time period in each iteration, the corresponding measurement time period for each iteration is calculated. Real-time interval average secondary combustion coefficient.

4. The optimized control method for combustible gas recovery as described in claim 3, characterized in that, For each iteration of the furnace, the fan speed is adjusted by a preset step length during the measurement time period, including: When at least one of the N measurement time periods in the current iteration furnace exists... If the real-time interval average secondary combustion coefficient is greater than the secondary combustion target value of the corresponding target smelting time zone, and there is no flue gas overflow from the converter during the current measurement period as detected by the configured thermal imager, differential pressure instrument, or manual observation, then the next furnace in the same measurement period... The following step is to subtract the preset step speed reduction length from the fan speed corresponding to the current iteration furnace and use this as the same measurement time period for the next iteration furnace. The first fan speed is used to operate the fan; During the fan operation corresponding to the first fan speed response, the measurement time period is synchronously measured within the corresponding iterative furnace cycle. The real-time interval average secondary combustion coefficient and flue gas overflow measurement results are used, and the fan speed adjustment of the remaining iteration furnace is repeated until the preset iteration furnace B or the interval average secondary combustion coefficient is minimized or the deviation from the target value corresponding to the M target smelting time zones meets the preset deviation threshold.

5. The optimized control method for combustible gas recovery as described in claim 4, characterized in that, The method of adjusting the fan speed by a preset step length during the measurement time period in each iteration of the furnace also includes: When at least one of the N measurement time periods in the current iteration furnace exists... If the real-time interval average secondary combustion coefficient is greater than the secondary combustion target value of the corresponding target smelting time zone, and flue gas overflow is detected during the current measurement period by the configured thermal imager, differential pressure instrument, or manual observation, then in the same measurement period of the next iteration furnace... Next, the fan speed corresponding to the current iteration furnace is used as the second fan speed for the same measurement time period of the remaining iteration furnaces, that is, the preset step speed reduction length is set to 0, and the fan operation is performed. Simultaneously, while performing the remaining iterations of the furnace under the second fan speed, measurements are simultaneously taken for each identical measurement time period under all iterations of the furnace. The real-time interval average secondary combustion coefficient and flue gas overflow measurement results are used until the preset iterative furnace number or the interval average secondary combustion coefficient is minimized or the deviation from the target value corresponding to the M target smelting time partitions meets the preset deviation threshold.

6. The optimized control method for combustible gas recovery as described in claim 5, characterized in that, The method of adjusting the fan speed by a preset step length during the measurement time period in each iteration of the furnace also includes: Statistics on the total number of actual iterative furnace runs within the same measurement time period The actual number of overflow iterations C corresponding to the flue gas overflow is used to calculate the measurement time period based on the ratio of the actual number of overflow iterations C to the total number of actual furnace iterations. Smoke incidence rate ; when If the smoke occurrence rate is less than the preset tolerance value D, then the fan speed corresponding to the current iteration furnace is determined to be the upper limit of the smoke occurrence speed, and the current speed is used as the measurement time period. The corresponding local optimal speed, and the real-time combustion coefficient corresponding to the current local optimal speed is the measurement time period. The corresponding local optimal interval average secondary combustion coefficient.

7. The optimized control method for combustible gas recovery as described in claim 6, characterized in that, The method of adjusting the fan speed by a preset step length during the measurement time period in each iteration of the furnace also includes: when When the smoke occurrence rate tolerance value D is greater than or equal to the preset value, the corresponding fan speed for the current iteration furnace is determined to be less than the upper limit of the smoke occurrence speed. In this case, the preset speed backtracking mechanism is triggered until the measurement period ends. corresponding The smoke rate is reduced to a preset tolerance value D. At the same time, the fan speed corresponding to the current smoke rate tolerance value D is taken as the local backtracking optimal speed for the measurement period. The interval average secondary combustion coefficient corresponding to the local backtracking optimal speed is taken as the local optimal interval average secondary combustion coefficient for the measurement period. The search process for the local optimal speed and the local optimal interval average secondary combustion coefficient corresponding to the repeated measurement time period involves synchronously searching for the local optimal speed and the local optimal interval average secondary combustion coefficient for N measurement time periods, and obtaining the sequence of local optimal speed and local optimal interval average secondary combustion coefficient corresponding to each measurement time period.

8. The optimized control method for combustible gas recovery as described in claim 7, characterized in that, The process of detecting flue gas overflow during the current measurement time period through a configured thermal imager, differential pressure instrument, or manual observation includes: The configured thermal imager is used to acquire infrared thermal imaging temperature field distribution or flue gas overflow data in the converter mouth area, and / or the differential pressure in the converter mouth area is acquired simultaneously through a differential pressure instrument. Based on the temperature field distribution data or flue gas overflow data and differential pressure, when an abnormal flue gas plume is detected and the differential pressure is greater than the preset differential pressure threshold, it is determined that flue gas has escaped from the converter furnace mouth.

9. An optimized control system for combustible gas recovery, used to implement the optimized control method for combustible gas recovery according to any one of claims 1-8, characterized in that, include: The module consists of the first partition module, the second partition module, the mapping module, the speed adjustment module, and the global optimization module. The first partitioning module is used to set N measurement time periods and calculate the real-time interval average secondary combustion coefficient sequence within the N measurement time periods during the smelting process; The second partitioning module is used to simultaneously set M target smelting time partitions in the same smelting process, set secondary combustion target values, and obtain a sequence of secondary combustion target values ​​for each target smelting time partition, wherein... ; The mapping module is used to set the initial fan speed and smoke occurrence rate tolerance value, respond to the initial fan speed, and determine the correspondence between the real-time interval average secondary combustion coefficient sequence and the M target smelting time partitions based on the measurement time period corresponding to the measured real-time interval average secondary combustion coefficient sequence and the timestamp relationship between the target smelting time partitions. The speed adjustment module is used to adjust the fan speed within the measurement time period in each iteration according to the real-time interval average secondary combustion coefficient sequence and the corresponding relationship between the M target smelting time zones. If the real-time interval average secondary combustion coefficient of any measurement time period within the N measurement time periods is greater than the secondary combustion target value of the corresponding target smelting time zone, then, under the condition of the smoke occurrence rate tolerance value, the fan speed within the measurement time period in each iteration furnace is adjusted by a preset step length, with the secondary combustion target value as the target iteration direction and combined with the speed backtracking mechanism, until the interval average secondary combustion coefficient of the measurement time period reaches the minimum or the deviation from the target value corresponding to the M target smelting time zones meets the preset deviation threshold. The global optimization module is used to repeat the measurement time period. The iterative furnace process for the corresponding interval-averaged secondary combustion coefficient, for all measurement time periods. The real-time interval average secondary combustion coefficient is iterated in the same furnace cycle, so that while meeting the smoke occurrence rate tolerance value, the real-time interval average secondary combustion coefficient of all measurement time periods in N measurement time periods reaches the minimum or the deviation from the target value corresponding to the M target smelting time partitions meets the preset deviation threshold. Combined with the combustion coefficient-fan speed mapping table, the fan speed parameters under the condition that the real-time interval average secondary combustion coefficient in N measurement time periods is met are obtained and encapsulated into a fan speed model. This represents the nth measurement time period in the smelting process corresponding to the bth iteration furnace.

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