A kiln control system based on a lime shaft kiln

Abstract

The present invention belongs to the field of intelligent measurement and control technology for kilns, and specifically relates to a kiln control system based on a lime shaft kiln. By constructing a three-dimensional dynamic grid topology of the countercurrent calcination zone in real time, the spatio-temporal alignment of the air velocity vector field, temperature gradient field and dynamic material distribution field is realized, and the material migration path within a preset time window and the critical air velocity required for suspension under the predicted evolution particle size conditions of each path node are accurately predicted. Based on the deviation between the actual air velocity received by the material and the critical value, the matching degree of the current opening of the axial air door group in the countercurrent calcination zone to the material suspension efficiency is quantified. When it is judged that the matching degree does not meet the standard, a precise air door control instruction is generated based on the spatial distribution of abnormal nodes, driving the servo mechanism to execute and trigger a closed-loop feedback, realizing the dynamic coupling of the suspension requirements of the current and future short-time sequence materials, breaking through the traditional lag control mode, so as to significantly improve the calcination efficiency and energy consumption control level of the lime shaft kiln.

Description

Technical Field

[0001] The present invention belongs to the technical field of intelligent measurement and control of kilns, and specifically relates to a kiln control system based on a lime shaft kiln. Background Art

[0002] As the core equipment for the high-temperature decomposition of calcium carbonate, the lime shaft kiln is widely used in the fields of building materials, metallurgy, etc. by virtue of the countercurrent calcination process. Its thermal efficiency and emission control directly affect production efficiency.

[0003] Existing technologies already have solutions related to the control of lime shaft kilns. For example, the lime vertical shaft automation processing device with the Chinese authorization announcement number CN205827160U optimizes the calcination process through a conveying chain and temperature monitoring. Another example is the lime kiln remote monitoring and control system with the Chinese authorization announcement number CN205692022U, which relies on an industrial control computer and a remote system to achieve parameter acquisition and process regulation, reducing costs and improving efficiency.

[0004] However, although existing technologies such as the above-mentioned solutions achieve basic process control through means such as automated conveying chains and remote parameter monitoring, their control logic still focuses on the discrete adjustment of static parameters such as temperature and pressure, and does not deeply couple the dynamic interaction analysis of gas-solid two-phase flows. Specifically, existing technologies lack a refined damper control mechanism with the dynamic suspension state of materials as the core regulation basis, and do not fully recognize the key role of the dynamic suspension state of materials in energy consumption optimization and intelligent production during the calcination process of lime kilns. This leads to damper control relying on empirical thresholds, with lagging responses and being crude, not only causing suspension failure and uneven calcination, but also resulting in fluctuations in thermal efficiency and the risk of abnormal caking, seriously restricting the operation stability of the kiln and the space for energy efficiency optimization. Summary of the Invention

[0005] In order to overcome the deficiencies in the background art, the embodiments of the present invention provide a kiln control system based on a lime shaft kiln, which can effectively solve the problems involved in the above-mentioned background art.

[0006] The object of the present invention can be achieved through the following technical solutions: A kiln control system based on a lime shaft kiln includes: a data acquisition module, a material migration prediction module, a suspension efficiency matching module, a regulation instruction generation module, and a control execution module.

[0007] The data acquisition module is connected to the material migration prediction module, the material migration prediction module is connected to the suspension efficiency matching module, the suspension efficiency matching module is connected to the regulation instruction generation module, the regulation instruction generation module is connected to the control execution module, and the control execution module is connected to the data acquisition module.

[0008] The data acquisition module synchronously acquires a multi-source data set including an air flow velocity vector field, a temperature gradient field, and a dynamic material distribution field in the countercurrent calcination zone.

[0009] The material migration prediction module inputs the multi-source data set into a pre-constructed material migration prediction model, and based on the three-dimensional discretization modeling of the countercurrent calcination zone, outputs a prediction map of the migration paths of each material within a preset time window. Each path node in the map is marked with the critical air flow velocity required for the material to achieve suspension under the predicted evolution particle size conditions.

[0010] The suspension efficiency matching module performs spatio-temporal registration on the migration path prediction map and the air flow velocity vector field, identifies a set of abnormal nodes where the deviation between the actual air flow velocity and the critical value on each material migration path prediction map exceeds the preset tolerance range, and thereby quantifies the matching degree of the current opening degree of the axial air damper group in the countercurrent calcination zone to the material suspension efficiency.

[0011] The regulation instruction generation module, when the matching degree is lower than the preset compliance threshold, performs spatial matching on the spatial coordinates of the abnormal nodes and the air flow coverage area of the axial air damper group, and generates a set of regulation instructions including the damper number, the regulation direction of the opening degree, and the regulation value in combination with a preset air flow compensation strategy.

[0012] The control execution module drives the axial air damper group to execute the set of regulation instructions through a servo mechanism, and triggers the data acquisition module to start a new round of monitoring after completion of the adjustment.

[0013] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects: (1) The present invention takes quantifying the matching degree of the current opening degree of the axial air damper group in the countercurrent calcination zone to the material suspension efficiency as the core. When it is determined that the matching degree does not meet the standard, precise damper regulation instructions are generated based on the spatial distribution of abnormal nodes, driving the servo mechanism to execute and triggering closed-loop feedback, realizing the dynamic coupling of the current and future short-time sequence material suspension requirements, breaking through the traditional lag regulation mode, and significantly improving the calcination efficiency and energy consumption control level of the lime shaft kiln.

[0014] (2) The present invention realizes the spatio-temporal alignment of the air flow velocity vector field, the temperature gradient field, and the dynamic material distribution field by constructing a three-dimensional dynamic grid topology of the countercurrent calcination zone, accurately predicts the material migration paths within a preset time window and the critical air flow velocity required for suspension under the predicted evolution particle size conditions of each path node, providing a basis for accurately generating a set of regulation instructions.

[0015] (3) The present invention performs spatial matching on the spatial coordinates of abnormal nodes and the air flow coverage area of the axial air damper group, intelligently determines the regulation direction of each axial air damper in the countercurrent calcination zone, and based on the dynamic correction of the reference opening degree regulation value, avoids the problems of local over-regulation or under-regulation caused by traditional extensive compensation, making the set of regulation instructions closely conform to the dynamic requirements of the material suspension efficiency.

[0016] (4) The present invention automatically triggers the correction of the instruction set by monitoring the convergence rate of the abnormal node deviation degree, ensuring that the instruction set is continuously optimized as the working condition evolves, so as to promote the high-closed-loop optimization of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention is further described with reference to the accompanying drawings. However, the embodiments in the drawings do not constitute any limitation to the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to the following drawings without creative efforts.

[0018] Figure 1 It is a schematic diagram of the module connection of the present invention.

[0019] Figure 2 It is a schematic diagram of the logic for the pre-constructed material migration prediction model of the present invention to execute the output of the migration path prediction map.

[0020] Figure 3 It is a schematic diagram of the quantization logic for the matching degree of the current opening degree of the axial air door group in the countercurrent calcination zone of the present invention to the material suspension efficiency. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0022] Refer to Figure 1 As shown, the present invention provides a kiln control system based on a lime shaft kiln, including: a data acquisition module, a material migration prediction module, a suspension efficiency matching module, a regulation instruction generation module, and a control execution module.

[0023] The data acquisition module is connected to the material migration prediction module, the material migration prediction module is connected to the suspension efficiency matching module, the suspension efficiency matching module is connected to the regulation instruction generation module, the regulation instruction generation module and the control execution module are connected, and the control execution module is connected to the data acquisition module.

[0024] The embodiment of the present invention takes quantifying the matching degree of the current opening degree of the axial air door group in the countercurrent calcination zone to the material suspension efficiency as the core. When it is judged that the matching degree does not meet the standard, accurate air door regulation instructions are generated based on the spatial distribution of abnormal nodes, driving the servo mechanism to execute and trigger closed-loop feedback, realizing the dynamic coupling of the suspension requirements of the current and future short-time sequence materials, breaking through the traditional lag regulation mode, so as to significantly improve the calcination efficiency and energy consumption control level of the lime shaft kiln.

[0025] The data acquisition module synchronously acquires a multi-source data set including an air flow velocity vector field, a temperature gradient field, and a dynamic material distribution field in the countercurrent calcination zone.

[0026] In a preferred embodiment of the present invention, the dynamic material distribution field synchronously obtains the three-dimensional spatial coordinates and particle size distribution data of the materials inside the countercurrent calcination zone and at the feed port by using a high-frequency laser scanning device, and the scanning data at the feed port includes the pre-judgment information of the materials about to enter the countercurrent calcination zone within a preset time window.

[0027] It should be added that the above-mentioned air flow velocity vector field and temperature gradient field are respectively collected by a non-contact laser tester and a fiber Bragg grating sensor array in the countercurrent calcination zone. The air flow velocity vector field includes the velocity vectors of each point in the three-dimensional space of the countercurrent calcination zone, and the temperature gradient field includes the temperature sampling values of each point in the three-dimensional space of the countercurrent calcination zone.

[0028] The material migration prediction module inputs the multi-source data set into a pre-constructed material migration prediction model, and based on the three-dimensional discretization modeling of the countercurrent calcination zone, outputs a prediction map of the migration paths of each material within a preset time window, and the air flow critical velocity required for each material to achieve suspension under the predicted evolution particle size conditions is marked at each path node in the map.

[0029] Refer to Figure 2 As shown, in a preferred embodiment of the present invention, the process of the pre-constructed material migration prediction model executing the output of the migration path prediction map includes: A1. Based on the currently collected air flow velocity vector field and temperature gradient field data, a three-dimensional dynamic grid topology structure of the countercurrent calcination zone is constructed, and each grid cell code is attached with its corresponding environmental parameters, including air flow velocity, air flow direction angle, and temperature sampling value.

[0030] A2. Establish a spatial coordinate index of each current material through the dynamic material distribution field data and bind its initial monitored particle size.

[0031] A3. Load the material migration prediction model and execute: i. Perform three-dimensional space-time alignment of the current grid environmental parameters and the material spatial coordinate index to generate a fused feature tensor.

[0032] ii. Analyze the feature tensor based on the migration state transition matrix and output the displacement vector of each material in the next time step. The state transition matrix is obtained by jointly training the environmental field evolution data and the particle trajectory true value data under the historical operating conditions.

[0033] It should be noted that the above state transition matrix training process is subject to the constraints of momentum conservation and thermodynamics, and the conservation relationship between the momentum change rate of the particle group and the air flow kinetic energy loss rate is forcibly verified.

[0034] iii. Iteratively calculate the displacement vectors for all time steps within the preset time window to form the migration trajectory prediction chain for each material.

[0035] A4. Synthesize the trajectory prediction chain in the spatio-temporal dimension, and generate the migration path prediction map of each material within the preset time window through density field rendering.

[0036] In a preferred embodiment of the present invention, the process of obtaining the predicted evolution particle size of the material at each path node on the map includes: denoting the path node to be analyzed as the target node, tracing the migration path segment of the material from the previous path node to the target node, and extracting the time series of environmental parameters of all grid cells covered by the path segment, including the air flow velocity, temperature sampling value, and residence duration of each grid cell.

[0037] When the temperature sampling value of the grid cell reaches or exceeds the preset material oxidation trigger threshold, the grid cell is regarded as a high-temperature oxidation cell. The cumulative residence duration of the material in the high-temperature oxidation cells in this path segment is statistically calculated, and combined with the material oxidation rate characteristics, the thermal oxidation attenuation amount of the material particle size in this path segment is calculated.

[0038] It should be noted that the above preset material oxidation trigger threshold is determined by its material characteristics, and the specific value can be referred to the chemical property guidance manual corresponding to the material.

[0039] The specific calculation formula for the thermal oxidation attenuation amount of the material particle size in the path segment is as follows: Based on the Arrhenius equation, establish the oxidation rate characteristic function of the material affected by temperature. Substitute the average temperature value of the high-temperature oxidation cells in the path segment into the function to obtain the material oxidation rate. Take the product of the material oxidation rate and the cumulative residence duration of the material in the high-temperature oxidation cells in this path segment as the unilateral oxidation layer increment of the material. Since oxidation occurs simultaneously on both sides of the material surface, the thermal oxidation attenuation amount is taken as twice the unilateral oxidation layer increment of the material. It should be particularly noted that the Arrhenius equation is a classic equation in chemical kinetics to describe the influence of temperature on the reaction rate, which is a well-known existing technology and will not be elaborated here.

[0040] According to the relative deviation between the material migration speed and the air flow speed in each grid cell of the path segment, combined with the air flow density characteristics, calculate the cumulative collision energy of the material affected by the air flow in this path segment, and convert the cumulative collision energy into the equivalent particle size mechanical wear amount through the pre-stored material hardness-wear response relationship.

[0041] It should be noted that the specific calculation process of the cumulative collision energy of the material affected by the air flow in this path segment is as follows: Regard the material as a regular geometric shape, such as a sphere. Calculate the material volume according to the particle size obtained in real time, multiply the volume by the preset material density to obtain the mass, and then convert it into the material weight in combination with the gravitational acceleration.

[0042] According to the relative deviation value between the material migration speed and the air flow speed, calculate the single-particle kinetic energy in combination with the material weight. Through the residence time - collision times mapping relationship table calibrated by experiments, look up the corresponding collision times according to the residence time of the grid cell, and multiply the single-particle kinetic energy by the collision times to obtain the collision energy within a single grid cell.

[0043] Traverse all grid cells within the path segment, accumulate the collision energy of each grid cell, and obtain the cumulative collision energy of the material under the influence of the air flow in this path segment.

[0044] The above-mentioned pre-stored material hardness - wear response relationship specifically refers to the corresponding relationship table or function between material hardness and wear coefficient established in advance through experiments. The specific process of converting the cumulative collision energy into the mechanical wear amount of the equivalent particle size is as follows: Retrieve the standard hardness specified in the chemical property guidance manual corresponding to the material based on the material property characteristics, synchronously retrieve the wear coefficient corresponding to this standard hardness, and use the product of this wear coefficient and the cumulative collision energy as the mechanical wear amount of the particle size.

[0045] Successively deduct the thermal oxidation attenuation amount and the mechanical wear amount from the initial monitored particle size of the previous path node to obtain the predicted evolution particle size of the target node, and further use it as the initial monitored particle size of the next path node, and recursively calculate the predicted evolution particle size of the material at each path node along the migration path prediction map.

[0046] In a preferred embodiment of the present invention, the process for determining the material migration speed of each grid cell in the path segment includes: obtaining the migration direction of the material from each grid cell to the next grid cell on its migration trajectory prediction chain, decomposing the effective displacement amount along the migration direction, and taking the ratio of the effective displacement amount to the residence time of the grid cell where the material is located as the migration speed.

[0047] In a preferred embodiment of the present invention, the critical suspension air flow speed required for the material to achieve suspension at the predicted evolution particle size is obtained through dynamic resistance balance calculation. Among them, the morphological characteristics of the material are introduced to dynamically correct the gas-solid interaction force, and the suspension mechanical conditions adapted to the flow field environment are established.

[0048] It should be noted that the Stokes correction formula can be used as a mathematical means for realizing the above dynamic resistance balance calculation. The Stokes correction formula is an adaptive adjustment of the classical Stokes law for the material flow scenario in the countercurrent calcination zone. The specific expression of this formula is: , where is the preset material density determined based on the material, is the gas density calculated through the ideal gas state equation according to the measured temperature and pressure in the countercurrent calcination zone, is the preset gravitational acceleration, is the predicted evolution particle size of the material, is the preset gas dynamic viscosity, which can be obtained by calculating the temperature in the countercurrent calcination zone through the Sutherland formula. is the preset shape correction factor, which is calibrated after quantifying the deviation of the material geometry from the standard sphere by a high-frequency laser scanning device, and is used to characterize the resistance characteristic differences of non-spherical particles. Its value range can be .

[0049] In the embodiment of the present invention, by constructing a three-dimensional dynamic grid topology of the countercurrent calcination zone, the spatio-temporal alignment of the air flow velocity vector field, the temperature gradient field and the dynamic material distribution field is realized, and the migration path of the material within the preset time window and the critical air flow velocity required for suspension under the predicted evolution particle size conditions at each path node are accurately predicted, providing a basis for accurately generating a regulation instruction set.

[0050] The suspension efficiency matching module performs spatio-temporal registration on the migration path prediction map and the air flow velocity vector field, and identifies a set of abnormal nodes in the predicted maps of the actual air flow velocities received by each material migration path that deviate from the critical value beyond the preset tolerance range, so as to quantify the matching degree of the current opening degree of the axial air door group in the countercurrent calcination zone to the material suspension efficiency.

[0051] Referring to Figure 3 As shown in a preferred embodiment of the present invention, the process of quantifying the matching degree of the current opening degree of the axial air door group in the countercurrent calcination zone to the material suspension efficiency includes: B1. Count the proportion of normal nodes in the predicted maps of the migration paths of the existing materials inside the countercurrent calcination zone, and obtain the matching degree of the current opening degree of the axial air door group to the suspension efficiency of the existing materials inside through mean value calculation. The proportion of normal nodes is the absolute difference between the proportion of abnormal nodes and 1.

[0052] B2. Based on the scanning data at the feeding port, mark the materials about to enter the countercurrent calcination zone within the preset time window as pre-entering materials, count the proportion of normal nodes in the predicted maps of the migration paths of each pre-entering material in the countercurrent calcination zone, and similarly obtain the matching degree of the current opening degree of the axial air door group to the suspension efficiency of the pre-entering materials.

[0053] B3. Screen the minimum matching degree among the suspension efficiencies of the existing materials inside and the pre-entering materials as the matching degree of the current opening degree of the axial air door group in the countercurrent calcination zone to the material suspension efficiency.

[0054] When the matching degree is lower than the preset standard threshold, the regulation instruction generation module performs spatial matching on the spatial coordinates of the abnormal nodes and the air flow coverage area of the axial air door group, and generates a regulation instruction set including the air door number, the opening degree regulation direction and the regulation value in combination with the preset air flow compensation strategy.

[0055] In a preferred embodiment of the present invention, the preset airflow compensation strategy includes the following: integrating the set of abnormal nodes in the predicted maps of each material migration path, and aggregating the abnormal nodes within the airflow coverage area of the same axial air damper into an abnormal node cluster.

[0056] Compare the quantity differences between the over-limit and under-limit abnormal nodes in the abnormal node clusters corresponding to each axial air damper, determine the opening adjustment direction of each axial air damper, and determine the airflow compensation speed in the corresponding direction.

[0057] It should be added that if the opening adjustment direction of the axial air damper is upward adjustment, retrieve the absolute difference between the actual airflow speed received by the materials of each under-limit abnormal node in the abnormal node cluster corresponding to the axial air damper and the critical value, and calculate the airflow compensation speed in the upward adjustment direction through average calculation. If the opening adjustment direction of the axial air damper is downward adjustment, retrieve the absolute difference between the actual airflow speed received by the materials of each over-limit abnormal node in the abnormal node cluster corresponding to the axial air damper and the critical value, and similarly obtain the airflow compensation speed in the downward adjustment direction.

[0058] Take the product of the airflow compensation speed of each axial air damper and the preset air damper opening-flow velocity gain coefficient as the reference opening adjustment value of each axial air damper. When the matching degrees of the current openings of the axial air damper group to the suspension efficiencies of the existing materials and the pre-incoming materials inside are both lower than the preset standard threshold, use the reference opening adjustment value of each axial air damper as its final opening adjustment value. When any matching degree is higher than the preset standard threshold, construct a compensation attenuation factor to correct the reference opening adjustment value of each axial air damper to obtain the final opening adjustment value.

[0059] It should be added that the above preset air damper opening-flow velocity gain coefficient is obtained by taking the derivative of the flow velocity response curve through the air damper opening step test in the initial stage of system development.

[0060] The specific construction process of the above compensation attenuation factor can refer to the following formula: , is the pre-calibrated attenuation rate control coefficient, is the preset standard threshold of the matching degree, is the matching degree exceeding the preset standard threshold. The formula mainly refers to the non-linear attenuation function, aiming to characterize that the greater the over-limit value of the matching degree with respect to the preset standard threshold, the faster the attenuation speed, and it is applicable to scenarios sensitive to high matching degrees.

[0061] In a preferred embodiment of the present invention, the determination process of the opening adjustment direction of the axial air damper includes: counting the number of over-limit abnormal nodes and the number of under-limit abnormal nodes in the abnormal node cluster corresponding to the axial air damper.

[0062] When the difference in the number of two types of abnormal nodes exceeds the preset difference threshold, if the number of abnormal nodes exceeding the upper limit is greater than the number of abnormal nodes exceeding the lower limit, it is determined that the adjustment direction of the axial air damper opening is downward; if the number of abnormal nodes exceeding the upper limit is less than the number of abnormal nodes exceeding the lower limit, it is determined that the adjustment direction of the axial air damper opening is upward.

[0063] When the difference in the number of two types of abnormal nodes does not reach the preset difference threshold, calculate the ratio of the sum of the absolute deviations of the actual air flow velocities received by the materials of the two types of abnormal nodes to the critical value. If the ratio is greater than 1, it is determined that the adjustment direction of the axial air damper opening is downward; otherwise, it is upward.

[0064] It should be noted that the ratio of the sum of the absolute deviations of the actual air flow velocities received by the materials of the two types of abnormal nodes to the critical value is specifically calculated with the sum of the absolute deviations of the actual air flow velocities received by the materials of the abnormal nodes exceeding the upper limit and the critical value as the numerator and the sum of the absolute deviations of the actual air flow velocities received by the materials of the abnormal nodes exceeding the lower limit and the critical value as the denominator.

[0065] In the embodiment of the present invention, through the spatial matching of the abnormal node spatial coordinates and the air flow coverage area of the axial air damper group, the adjustment direction of each axial air damper in the countercurrent calcination zone is intelligently determined, and based on the dynamic correction of the reference opening adjustment value, the problems of local over-adjustment or under-adjustment caused by traditional extensive compensation are avoided, so that the adjustment instruction set closely conforms to the dynamic requirements of the material suspension efficiency.

[0066] The control execution module drives the axial air damper group to execute the adjustment instruction set through the servo mechanism, and triggers the data acquisition module to start a new round of monitoring after the adjustment is completed.

[0067] In a preferred embodiment of the present invention, the control execution module further includes a feedback verification unit, which is used to perform the following operations after the axial air damper group executes the adjustment instruction set and before the data acquisition module starts a new round of monitoring: real-time monitor the change in the deviation degree between the actual air flow velocity received by each abnormal node set in the predicted material migration path map and the critical value, and calculate its convergence rate with the preset tolerance range based on the deviation degree time series data within the preset time window.

[0068] If the convergence rate is lower than the preset reasonable convergence rate threshold, an iterative adjustment request is sent, and the request includes the spatial feature data of the current deviation degree distribution to guide the correction of the original adjustment instruction set.

[0069] In the embodiment of the present invention, by monitoring the convergence rate of the deviation degree of the abnormal nodes, the instruction set correction is automatically triggered to ensure that the instruction set is continuously optimized with the evolution of the working conditions, so as to promote the high-level closed-loop optimization of the system.

[0070] All the above formulas are dimensionless and take their numerical values for calculation. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0071] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product.

[0072] Those of ordinary skill in the art will recognize that the modules and algorithm steps of each example described in connection with the embodiments disclosed herein can be implemented in electronic hardware or in a combination of computer software and electronic hardware. Whether these functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. A person skilled in the art can use different methods for each specific application to implement the described functions, but such implementation should not be considered to exceed the scope of this application.

[0073] In addition, each functional module in the various embodiments of this application can be integrated into one processing module, or each module can exist physically alone, or two or more modules can be integrated into one module.

[0074] As mentioned above, this is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application, and all such changes or substitutions should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

[0075] Finally, the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A kiln control system based on a lime shaft kiln, characterized in that, The system includes: A data acquisition module that synchronously acquires a multi-source data set including an air flow velocity vector field, a temperature gradient field, and a dynamic material distribution field within the countercurrent calcination zone; A material migration prediction module that inputs the multi-source data set into a pre-constructed material migration prediction model. Based on the three-dimensional discretization modeling of the countercurrent calcination zone, it outputs a prediction map of the migration paths of each material within a preset time window. Each path node in the map is marked with the critical air flow velocity required for the material to achieve suspension under the predicted evolution particle size conditions; A suspension efficiency matching module that performs spatio-temporal registration on the migration path prediction map and the air flow velocity vector field, identifies a set of abnormal nodes where the deviation between the actual air flow velocity and the critical air flow velocity on each material migration path prediction map exceeds the preset tolerance range, and thereby quantifies the matching degree of the current opening degree of the axial air damper group within the countercurrent calcination zone to the material suspension efficiency; A regulation instruction generation module that, when the matching degree is lower than the preset compliance threshold, performs spatial matching on the spatial coordinates of the abnormal nodes and the air flow coverage area of the axial air damper group, and generates a set of regulation instructions including the damper number, the regulation direction of the opening degree, and the regulation value in combination with a preset air flow compensation strategy; A control execution module that drives the axial air damper group to execute the set of regulation instructions through a servo mechanism, and triggers the data acquisition module to start a new round of monitoring after completion of the adjustment; The process of obtaining the predicted evolution particle size of the material at each path node on the map includes: marking the path node to be analyzed as the target node, tracing the migration path segment of the material from the previous path node to the target node, and extracting the time series of environmental parameters of all grid cells covered by the path segment, including the air flow velocity, temperature sampling values, and residence duration of each grid cell; When the temperature sampling value of the grid cell reaches or exceeds the preset material oxidation trigger threshold, the grid cell is regarded as a high-temperature oxidation cell. The cumulative residence duration of the material in the high-temperature oxidation cells in this path segment is statistically calculated, and the thermal oxidation attenuation amount of the material particle size in the path segment is calculated in combination with the material oxidation rate characteristics; According to the relative deviation between the material migration velocity and the air flow velocity in each grid cell of the path segment, and in combination with the air flow density characteristics, the cumulative collision energy of the material under the influence of the air flow in this path segment is calculated, and the cumulative collision energy is converted into an equivalent particle size mechanical wear amount through a pre-stored material hardness-wear response relationship; The initial monitored particle size of the previous path node is successively deducted from the thermal oxidation attenuation amount and the mechanical wear amount to obtain the predicted evolution particle size of the target node, and it is further used as the initial monitored particle size of the next path node, and the predicted evolution particle size of the material at each path node is recursively calculated along the migration path prediction map.

2. The kiln control system based on a lime shaft kiln according to claim 1, characterized in that: The dynamic material distribution field synchronously obtains the three-dimensional spatial coordinates and particle size distribution data of the materials inside the countercurrent calcination zone and at the feed port by using a high-frequency laser scanning device. The scanning data at the feed port includes the pre-judgment information of the materials that will enter the countercurrent calcination zone within a preset time window.

3. The kiln control system based on a lime shaft kiln according to claim 1, wherein: The process of the pre-constructed material migration prediction model performing the output of the migration path prediction map includes: A1. Based on the currently collected air velocity vector field and temperature gradient field data, construct a three-dimensional dynamic grid topological structure for the countercurrent calcination zone. Each grid cell is encoded with its corresponding environmental parameters, including air velocity, air direction angle, and temperature sampling value. A2. Establish the spatial coordinate index of each current material through the dynamic material distribution field data and bind its initial monitored particle size. A3. Load the material migration prediction model and execute: i. Align the current grid environmental parameters and the material spatial coordinate index in three-dimensional space-time to generate a fused feature tensor. ii. Analyze the feature tensor based on the migration state transition matrix and output the displacement vector of each material at the next time step. The state transition matrix is obtained by jointly training with the environmental field evolution data and the true particle trajectory data under historical operating conditions. iii. Iteratively calculate the displacement vectors of all time steps within a preset time window to form a migration trajectory prediction chain for each material. A4. Synthesize the trajectory prediction chain in the space-time dimension and generate a migration path prediction map of each material within a preset time window through density field rendering.

4. The kiln control system based on a lime shaft kiln according to claim 1, wherein: The determination process of the material migration speed of each grid cell in the path segment includes: obtaining the migration direction of the material from each grid cell to the next grid cell on its migration trajectory prediction chain, decomposing the effective displacement along the migration direction, and taking the ratio of the effective displacement to the residence time of the grid cell where the material is located as the migration speed.

5. A kiln control system based on a lime shaft kiln according to claim 1, characterized in that: The critical air suspension speed required for the material to achieve suspension at the predicted evolution particle size is obtained through dynamic resistance balance calculation. Among them, the particle shape characteristics are introduced to dynamically correct the gas-solid interaction force, and a suspension mechanical condition adapted to the flow field environment is established.

6. The kiln control system based on a lime shaft kiln according to claim 2, wherein: The quantization process of the matching degree of the current opening degree of the axial air door group in the countercurrent calcination zone to the material suspension efficiency includes: B1. Statistically calculate the proportion of normal nodes in the migration path prediction maps of each current material existing inside the countercurrent calcination zone, and obtain the matching degree of the current opening degree of the axial air door group to the suspension efficiency of the existing materials inside through mean calculation. The proportion of normal nodes is the absolute difference between the proportion of abnormal nodes and 1. B2. Based on the scanning data at the feed port, mark the materials that will enter the countercurrent calcination zone within a preset time window as pre-feed materials, and statistically calculate the proportion of normal nodes in the migration path prediction maps of each pre-feed material in the countercurrent calcination zone. Similarly, obtain the matching degree of the current opening degree of the axial air door group to the suspension efficiency of the pre-feed materials. B3. Screen the minimum matching degree among the suspension efficiencies of the existing materials inside and the pre-feed materials, as the matching degree of the current opening degree of the axial air door group in the countercurrent calcination zone to the material suspension efficiency.

7. A furnace control system based on a lime shaft kiln according to claim 1, characterized in that: The preset air flow compensation strategy includes the following: Integrate the abnormal node sets in the migration path prediction maps of each material, and aggregate the abnormal nodes within the air flow coverage area of the same axial air door into an abnormal node cluster. Compare the quantity differences of the abnormal nodes above the upper limit and below the lower limit in the abnormal node clusters corresponding to each axial air door, determine the opening degree adjustment direction of each axial air door and determine the air flow compensation speed in the corresponding direction. Multiply the air flow compensation speed of each axial air door by the preset air door opening - flow rate gain coefficient to obtain the reference opening control value of each axial air door. When the matching degrees of the current opening of the axial air door group to the suspension efficiency of the existing internal materials and the pre - incoming materials are both lower than the preset standard threshold, use the reference opening control value of each axial air door as its final opening control value. When any matching degree is higher than the preset standard threshold, construct a compensation attenuation factor to correct the reference opening control value of each axial air door to obtain the final opening control value.

8. A furnace control system based on a lime shaft kiln according to claim 7, characterized in that: The determination process of the control direction of the axial air door opening includes: counting the number of over - upper - limit abnormal nodes and the number of over - lower - limit abnormal nodes in the abnormal node cluster corresponding to the axial air door; Under the condition that the difference between the numbers of the two types of abnormal nodes exceeds the preset difference threshold, if the number of over - upper - limit abnormal nodes is greater than the number of over - lower - limit abnormal nodes, determine that the control direction of the axial air door opening is downward adjustment; if the number of over - upper - limit abnormal nodes is less than the number of over - lower - limit abnormal nodes, determine that the control direction of the axial air door opening is upward adjustment; Under the condition that the difference between the numbers of the two types of abnormal nodes does not reach the preset difference threshold, calculate the ratio of the sum of the absolute deviations of the actual air flow velocities of the materials at the abnormal nodes of the two types to the air flow critical velocity. If the ratio is greater than 1, determine that the control direction of the axial air door opening is downward adjustment; otherwise, it is upward adjustment; The above ratio calculation uses the sum of the absolute deviations of the actual air flow velocities of the materials at the over - upper - limit abnormal nodes from the critical value as the numerator and the sum of the absolute deviations of the actual air flow velocities of the materials at the over - lower - limit abnormal nodes from the critical value as the denominator.

9. A furnace control system based on a lime shaft kiln according to claim 1, characterized in that: The control execution module further includes a feedback verification unit, which is used to perform the following operations after the axial air door group executes the control instruction set and before the data acquisition module starts a new round of monitoring: real - time monitor the change in the deviation degree between the actual air flow velocity and the air flow critical velocity in the abnormal node set of each material migration path prediction map, and calculate its convergence rate with the preset tolerance range based on the deviation degree time - series data within the preset time window; If the convergence rate is lower than the preset reasonable threshold of the convergence rate, send an iterative control request, and the request includes the spatial feature data of the current deviation degree distribution to guide the correction of the original control instruction set.

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