An industrial harmful waste gas pretreatment and heat accumulation incineration system

Abstract

The present application relates to industrial waste gas treatment technical field, disclose a kind of industrial harmful waste gas pretreatment and heat accumulation incineration system, including data analysis module, mapping operation module, asymmetric scheduling module, coupled operation module and inertia feedforward module;Data analysis module obtains physical sensing and process equipment action signal and establishes initial air mass team queue;Mapping operation module calculates residual transport time and potential reaction enthalpy value;Asymmetric scheduling module lengthens target heat accumulation ceramic bed exhaust cycle time when thermal load is overrun;Coupled operation module generates fluid resistance coefficient decay amount based on temperature drop parameter;Inertia feedforward module generates feedforward control instruction in combination with main induced draft fan rotational inertia constant, and is output to frequency converter before downstream switching valve group action.This application eliminates sensor response hysteresis effect, avoids overtemperature shutdown by releasing heat in advance, and offsets fan mechanical hysteresis, maintains pipe network negative pressure stability.

Description

Technical Field

[0001] This invention relates to the field of industrial waste gas treatment technology, specifically to an industrial hazardous waste gas pretreatment and regenerative thermal incineration system. Background Technology

[0002] In industrial production, volatile organic waste gas generated by process equipment is treated by thermal oxidation using a regenerative thermal incineration system. The regenerative thermal incineration system recovers and releases heat by periodically switching the airflow direction and using a porous regenerative ceramic bed to maintain the reaction temperature of the combustion chamber and reduce energy consumption. During the operation of upstream process equipment, sudden high-concentration waste gas clouds are often generated in the waste gas main pipe due to the discrete operation of the process equipment.

[0003] Existing regenerative thermal ignition (RTO) control systems primarily rely on fluid concentration sensors installed on exhaust gas ducts to acquire exhaust gas concentration data. Conventional fluid concentration sensors exhibit physical response lag when detecting sudden changes in exhaust gas concentration, causing the concentration values ​​acquired by the control system to lag behind the actual fluid state in the pipeline network. This detection lag prevents the system from anticipating the arrival of high-concentration gas masses. When undetected high-concentration exhaust gas directly enters the combustion chamber, its violent oxidation releases a large amount of heat, causing a transient thermal load shock to the system. Current control systems employ fixed symmetrical isochronous switching logic to control the intake and exhaust cycles of each RTO ceramic bed. When faced with sudden thermal shocks, this symmetrical isochronous switching logic cannot preemptively remove the heat accumulated inside the porous ceramic body, leading to an abnormal increase in the longitudinal temperature gradient of the porous ceramic bed, causing combustion chamber overheating, or even equipment protective shutdown.

[0004] Meanwhile, drastic changes in the internal temperature field of porous ceramic media can alter the dynamic viscosity of the internal gas, leading to a nonlinear abrupt change in the fluid friction resistance of the regenerative ceramic bed. Traditional exhaust gas pipeline pressure control strategies often employ proportional-integral-derivative (PID) control algorithms based on pressure sensor feedback to adjust the speed of the main induced draft fan. Due to the large rotational inertia of the mechanical rotor of the high-power main induced draft fan, there is a physical time lag between receiving the deceleration command and the actual reduction in impeller speed. At the instant when the fluid resistance of the ceramic bed suddenly decreases due to temperature rise, the lag in feedback control can cause the induced draft fan to continue operating at a high speed. This can result in excessive pipeline suction, causing instantaneous flow rate fluctuations that exceed limits, disrupting the micro-negative pressure boundary conditions required for the operation of the regenerative incineration equipment, and increasing the risk of industrial exhaust gas spillage. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an industrial hazardous waste gas pretreatment and regenerative thermal incineration system. This system solves the problems of existing systems being unable to intervene in advance when dealing with sudden changes in waste gas concentration, such as overheating shutdown caused by the sluggish physical response of sensors and main induced draft fans, and negative pressure instability caused by sudden changes in pipeline fluid resistance.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: an industrial hazardous waste gas pretreatment and regenerative thermal incineration system, the system comprising: a data parsing module, used to acquire physical sensor signals and discrete action signals of process equipment, perform processing according to a set time step, and establish an initial gas flow pattern containing effective instantaneous concentration state values ​​and instantaneous flow state values ​​of waste gas;

[0007] The mapping operation module is used to read the initial gas column, perform variable upper limit integral operation to calculate the remaining transport time to the downstream switching valve group, and combine it with the standard combustion heat enthalpy constant of the target volatile organic compound to calculate the potential reaction enthalpy value;

[0008] The asymmetric scheduling module is used to output a timing intervention command to the downstream switching valve group to extend the exhaust cycle time of the target thermal regenerator ceramic bed when the potential reaction enthalpy value is greater than the set safe heat load threshold and the remaining transport time meets the set conditions.

[0009] The coupled computation module is used to extract the temperature drop parameters corresponding to the extension of the exhaust cycle time of the target thermal regenerator ceramic bed, solve the transient gas dynamic viscosity value, and generate the transient fluid resistance coefficient attenuation.

[0010] The inertia feedforward module is used to calculate the total pressure compensation of the system based on the attenuation of the transient fluid resistance coefficient, and generate feedforward control commands in combination with the rotational inertia constant of the main induced draft fan. These commands are then output to the main induced draft fan frequency converter before the downstream switching valve group is activated.

[0011] The system of this invention uses a data parsing module and a mapping operation module to discretize the data, converting the continuous material transport process in the pipeline into a data queue update, thus eliminating the impact of sensor hardware response lag. The asymmetric scheduling module controls the switching valve group to operate in advance based on the prediction results of the potential reaction enthalpy value, reserving heat capacity receiving space for the combustion chamber in advance. The coupled operation module and the inertia feedforward module combine the calculation relationship of fluid dynamics and thermodynamic parameters, and use the time difference of the exhaust gas transmission in the pipeline to issue control commands to the main induced draft fan frequency converter before the switching valve group operates, thereby offsetting the mechanical response lag of the main induced draft fan rotor and maintaining the stable operation of the regenerative thermal combustion system.

[0012] Furthermore, the data analysis module has internal logic for determining concentration status. When the discrete action signal of the process equipment undergoes a level transition, the data analysis module calls a preset empirical concentration calibration value as the effective instantaneous concentration status value within the corresponding time step within a preset concentration holding time window. When the discrete action signal of the process equipment remains at a zero level, the data analysis module calls the physical sensing value of the physical sensing signal as the effective instantaneous concentration status value, thereby covering the physical response hysteresis time window of conventional fluid concentration sensors.

[0013] In the above technical solution, the data analysis module adopts a state jump capture and empirical calibration value overlay mechanism to compensate for the measurement data distortion of the fluid concentration sensor in the early stage of sudden change in exhaust gas concentration, and ensure the continuity of the data required for subsequent state prediction.

[0014] Furthermore, the data parsing module is specifically used to encapsulate the absolute timestamp, effective instantaneous concentration status value, and exhaust gas instantaneous flow status value into a single data structure within each set time step, and allocate the remaining distance from the downstream switching valve group within the single data structure; and within each control cycle, calculate the gas mass displacement based on the division operation value of the exhaust gas instantaneous flow status value and the physical cross-sectional area of ​​the exhaust gas main pipe, perform a decremental update on the remaining distance in the single data structure, and establish an initial gas mass queue characterizing the spatial material distribution by continuously executing enqueue operations.

[0015] By performing a single data structure update and enqueue operation in each control cycle, a data model reflecting the distribution of waste gas fluid inside the physical pipeline network is established, enabling spatial tracking and positioning of waste gas concentration inside the pipeline network.

[0016] Furthermore, the mapping operation module is specifically used to establish a variable upper limit integral equation. The variable upper limit integral equation uses the ratio of the instantaneous flow rate of the exhaust gas to the physical cross-sectional area of ​​the exhaust gas main pipe as the integrand to perform discrete accumulation operation. When the accumulated displacement value obtained by discrete accumulation calculation is equal to the physical length of the exhaust gas main pipe between the data acquisition unit and the downstream switching valve group, the upper limit parameter of the integral when the trigger equation is true is extracted, and the upper limit parameter of the integral is used as the remaining transport time for the corresponding discrete gas mass to reach the downstream switching valve group.

[0017] The above variable upper limit integral calculation converts the physical length of the exhaust manifold into a predicted transport time that fluctuates with the flow rate, providing a time buffer window for the generation and advance output of feedforward control commands.

[0018] Furthermore, the mapping operation module is pre-set with the standard enthalpy constant of the target volatile organic compound and a set time step constant. Specifically, the mapping operation module is used to perform a series of multiplication operations on the effective instantaneous concentration state value, the instantaneous flow state value of the exhaust gas, the set time step constant, and the standard enthalpy constant of the target volatile organic compound. The product obtained by the series of multiplication operations is used as the potential reaction enthalpy value released after the corresponding discrete gas mass enters the combustion chamber.

[0019] The above calculation process transforms parameters such as the effective instantaneous concentration state value and the instantaneous flow state value of the exhaust gas into a potential reaction enthalpy value that reflects the degree of heat load impact, providing a direct basis for triggering the asymmetric scheduling module.

[0020] Furthermore, the specific setting condition is that the remaining transport time is greater than or equal to the sum of the system preparation time and the planned extended target exhaust cycle time of the regenerative ceramic bed; the asymmetric scheduling module is specifically used to calculate the difference between the potential reaction enthalpy and the set safe heat load threshold, multiply the difference by the set time compensation gain coefficient and then add it to the rated exhaust cycle time to obtain the actual exhaust cycle time, and use the amplitude limiting cutoff logic to forcibly constrain the actual exhaust cycle time within the preset maximum process allowable cycle time boundary.

[0021] When the aforementioned asymmetric scheduling module determines that a thermal shock has occurred and there is sufficient time buffer, it changes the switching cycle of the system's symmetric isochronous system. By extending the exhaust cycle time of the target thermal storage ceramic bed, it removes the heat accumulated inside the porous ceramic body, reduces the longitudinal temperature gradient of the target thermal storage ceramic bed, and avoids subsequent high-temperature failures in the system.

[0022] Furthermore, the coupling operation module stores a reference gas dynamic viscosity constant, a reference temperature constant, and a Sutherland constant related to the waste gas components. Specifically, the coupling operation module is used to subtract the temperature drop parameter from the reference operating absolute temperature of the target regenerative ceramic bed to obtain the actual operating absolute temperature. Using the reference gas dynamic viscosity constant, the reference temperature constant, the Sutherland constant, and the actual operating absolute temperature, the module performs algebraic operations based on the Sutherland empirical law formula to generate transient gas dynamic viscosity values.

[0023] The aforementioned coupled computation module, combined with Sutherland's empirical law formula, transforms the temperature change of the porous medium inside the target thermal storage ceramic bed into specific values ​​of fluid dynamic viscosity, establishing a computational correlation for the conversion of thermodynamic state to fluid dynamic parameters.

[0024] Furthermore, the coupling operation module is specifically used to extract the dynamic viscosity constant of the reference gas at the reference operating absolute temperature, calculate the difference between the dynamic viscosity constant of the reference gas and the dynamic viscosity value of the transient gas, and combine the effective filling height of the porous ceramic body, the physical calibration porosity of the porous ceramic body, the equivalent particle diameter of the porous ceramic body, and the empirical equivalence coefficient to perform an algebraic mapping operation on the difference between the dynamic viscosity constant of the reference gas and the dynamic viscosity value of the transient gas according to the viscous resistance term of the Eugen equation to obtain the attenuation of the transient fluid resistance coefficient.

[0025] The above calculation steps quantify the reduction in fluid friction resistance of porous ceramic bodies caused by the decrease in gas dynamic viscosity based on Eugen's equation, and obtain the attenuation of transient fluid resistance coefficient.

[0026] Furthermore, the inertia feedforward module is specifically used to smooth the real-time measured instantaneous mass flow rate of the exhaust gas using a first-order low-pass filtering algorithm, obtain the exhaust gas density parameter, divide the square of the smoothed instantaneous mass flow rate of the exhaust gas by twice the exhaust gas density parameter, and multiply the result by the transient fluid resistance coefficient attenuation to generate the system total pressure compensation.

[0027] Based on the correspondence between pipeline resistance and the square of mass flow rate, the aforementioned inertia feedforward module converts the attenuation of transient fluid resistance coefficient into the total system pressure compensation required to maintain the target suction flow rate. It also smooths the instantaneous mass flow rate of exhaust gas using a first-order low-pass filtering algorithm to reduce the interference of high-frequency airflow pulsation on the calculation results.

[0028] Furthermore, the feedforward control command is specifically a feedforward intervention frequency command; the inertia feedforward module is specifically used to obtain the reference total pressure value and reference operating speed before the fluid resistance mutation occurs, divide the difference between the reference total pressure value and the system total pressure compensation by the factory aerodynamic characteristic constant and perform a square root operation to generate the basic speed adjustment; perform a derivative operation with respect to absolute time on the system total pressure compensation to generate a compensation derivative term, multiply the compensation derivative term, the main induced draft fan rotational inertia constant and the engineering conversion coefficient together and divide by the rated electromagnetic torque of the main induced draft fan motor to generate an equivalent speed correction; subtract the reference operating speed, the basic speed adjustment, and the equivalent speed correction in sequence, and multiply the subtraction result by the ratio of the number of motor pole pairs to the constant to generate the feedforward intervention frequency command output to the main induced draft fan inverter.

[0029] The aforementioned inertia feedforward module, combined with the rotational inertia constant of the main induced draft fan, generates an equivalent speed correction amount. It converts the rotational inertia of the main induced draft fan's mechanical rotor into a pre-controlled compensation derivative term, enabling the variable frequency induced draft fan to perform speed adjustment actions in advance before the actual attenuation of fluid resistance occurs, thus avoiding excessive increase in the instantaneous flow rate of the pipeline network, which could lead to uncontrolled negative pressure in the system.

[0030] This invention provides an industrial hazardous waste gas pretreatment and regenerative thermal ignition system. It has the following beneficial effects:

[0031] 1. This invention uses a data parsing module to call a preset empirical concentration calibration value to cover the physical response hysteresis time window of the physical sensor signal, and uses a mapping operation module to perform variable upper limit integral operation on the initial gas column to calculate the remaining transport time. This solves the measurement distortion problem of conventional fluid sensors in the early stage of sudden changes in exhaust gas concentration. Based on the above-mentioned time dimension data discretization and spatial displacement accumulation operation, the control system can accurately predict the specific time when high concentration exhaust gas arrives at the downstream switching valve group, providing a reliable data foundation and absolute time buffer window for subsequent advance issuance of control commands.

[0032] 2. In this invention, when the potential reaction enthalpy is determined to be greater than the set safe heat load threshold and the remaining transport time condition is met, the asymmetric scheduling module outputs a timing intervention command to extend the exhaust cycle time of the target heat storage ceramic bed. The above control mechanism changes the original symmetrical isochronous operation rhythm of the system and uses the extended exhaust action to force the heat accumulated inside the porous ceramic body to be discharged, reduce the longitudinal temperature gradient of the target heat storage ceramic bed, prevent high concentration of exhaust gas from rushing into the combustion chamber and causing over-temperature shutdown failure, and improve the physical bearing capacity of the system to cope with sudden changes in heat load.

[0033] 3. This invention uses a coupled computation module to convert the temperature drop parameter into the transient fluid resistance coefficient attenuation based on the principle of porous media fluid dynamics. The inertia feedforward module calculates the equivalent speed correction based on the rotational inertia constant of the main induced draft fan, and outputs the feedforward intervention frequency command to the main induced draft fan inverter before the downstream switching valve group operates. The above computational logic establishes the computational correlation between temperature field changes and pipeline aerodynamic pressure compensation, enabling the variable frequency induced draft fan to perform electromagnetic torque unloading and impeller speed reduction actions in advance, offsetting the response lag caused by the inherent inertia of the fan's mechanical rotor, and avoiding instantaneous flow surge and negative pressure instability caused by sudden changes in pipeline fluid resistance. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the system architecture of the present invention;

[0035] Figure 2 This is a schematic diagram of the method flow of the present invention;

[0036] Figure 3 This is a schematic diagram of the reconstruction of multi-source discrete signals and effective concentrations according to the present invention;

[0037] Figure 4 This is a schematic diagram of the discrete gas column and variable upper limit integral mapping of the present invention;

[0038] Figure 5 This is a logical schematic diagram of the asymmetric scheduling module of the present invention;

[0039] Figure 6 This is a logical schematic diagram of the coupled operation module of the present invention;

[0040] Figure 7 This is a logic diagram of the inertia feedforward module of the present invention;

[0041] Figure 8 This is a schematic diagram showing the comprehensive comparison of control states under sudden change operating conditions in this invention.

[0042] Among them, 100 is the data parsing module; 200 is the mapping operation module; 300 is the asymmetric scheduling module; 400 is the coupling operation module; and 500 is the inertia feedforward module. Detailed Implementation

[0043] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] See attached document Figure 1 The present invention provides an industrial hazardous waste gas pretreatment and regenerative thermal incineration system, the system comprising: a data parsing module 100, a mapping operation module 200, an asymmetric scheduling module 300, a coupling operation module 400, and an inertia feedforward module 500.

[0045] The data parsing module 100 is used to acquire the physical sensing signals output by the data acquisition unit located upstream of the exhaust gas main pipe and the discrete action signals of the process equipment output by the upstream main control system. On the time axis, the physical sensing signals and the discrete action signals of the process equipment are discretized according to the set time step to establish an initial gas flow pattern containing information on the instantaneous concentration and instantaneous flow of exhaust gas.

[0046] The mapping operation module 200, connected to the data parsing module 100, is used to read the instantaneous flow data in the initial gas column, perform variable upper limit integral operation using the instantaneous flow data and the physical cross-sectional area of ​​the exhaust gas main, calculate the remaining transport time for each discrete gas column to reach the downstream switching valve group, and calculate the potential reaction enthalpy value of each discrete gas column entering the combustion chamber by combining the standard combustion heat enthalpy constant of the target volatile organic compound.

[0047] The asymmetric scheduling module 300, connected to the mapping calculation module 200, is used to receive the remaining transport time and the potential reaction enthalpy. When the potential reaction enthalpy is greater than the set safe heat load threshold and the remaining transport time is sufficient to cover the sum of the system preparation time and the planned extended exhaust cycle time, the asymmetric thermal scheduling state is triggered in advance, and a timing intervention command is output to the switching valve group. The timing intervention command extends the exhaust cycle time of the target heat storage ceramic bed that is currently in the heat release state, so as to reduce the longitudinal temperature gradient inside the target heat storage ceramic bed.

[0048] The coupling operation module 400 is connected to the asymmetric scheduling module 300. Under asymmetric thermal scheduling, it is used to extract the temperature drop parameter corresponding to the extension of the exhaust cycle of the target thermal storage ceramic bed, input the temperature drop parameter into the preset gas viscosity empirical formula to solve the corresponding transient gas dynamic viscosity value, and perform algebraic difference operation on the transient gas dynamic viscosity value based on the principle of porous media fluid dynamics to generate the transient fluid resistance coefficient attenuation.

[0049] The inertia feedforward module 500, connected to the coupling calculation module 400, is used to receive the fluid resistance coefficient attenuation amount, calculate the system total pressure compensation amount based on the fluid resistance coefficient attenuation amount, the instantaneous mass flow rate of the exhaust gas, and the exhaust gas density parameter, generate the feedforward frequency correction amount or negative torque correction amount of the main induced draft fan based on the system total pressure compensation amount, read the calibrated rotational inertia constant of the main induced draft fan rotor, generate the fan feedforward control command based on the system total pressure compensation amount, rotational inertia constant, pressure change rate, and engineering conversion coefficient, and output the feedforward control command to the frequency converter of the main induced draft fan at the time node before the switching valve group action occurs, so as to control the main induced draft fan to reduce the output torque or correct the speed in advance to offset the instantaneous flow surge caused by the fluid resistance attenuation.

[0050] See attached document Figure 2 This invention provides a method for pretreatment and regenerative thermal incineration of industrial hazardous waste gas, the method comprising the following steps:

[0051] S100 acquires physical sensor signals located upstream of the exhaust gas main pipe and discrete action signals of process equipment output by the upstream main control system, and performs discretization processing on the time axis to establish the initial gas flow sequence.

[0052] S200 reads the instantaneous flow data from the initial gas mass column, performs variable upper limit integration, calculates the remaining transport time for each discrete gas mass to reach the downstream switching valve group, and calculates the potential reaction enthalpy.

[0053] S300 assesses heat load risk based on remaining transport time and potential reaction enthalpy, triggers asymmetric thermal scheduling state in advance, and extends the exhaust cycle time of the target thermal regenerator ceramic bed through timing intervention commands to reduce the longitudinal temperature gradient.

[0054] S400 extracts temperature drop parameters under asymmetric thermal scheduling, solves for transient gas dynamic viscosity values, and generates transient fluid resistance coefficient attenuation based on porous media fluid dynamics principles.

[0055] S500 calculates the total pressure compensation of the system based on parameters such as the attenuation of fluid resistance coefficient, generates feedforward control commands, and outputs them to the main induced draft fan frequency converter before the switching valve group operates to offset the instantaneous flow surge.

[0056] See attached document Figure 3The data parsing module 100 acquires the physical sensing signals output by the data acquisition unit located upstream of the exhaust gas main in real time via a fieldbus. The physical sensing signals specifically include the analog quantity of volatile organic compound concentration and the analog quantity of exhaust gas velocity. The data parsing module 100 is equipped with a high-frequency hardware timer. A fixed sampling period is set through the high-frequency hardware timer as the time step for discretization processing. The time step value ranges from 0.1s to 0.5s. The specific hardware implementation of the analog-to-digital conversion of the physical sensing signals can be designed based on the existing high-precision industrial isolated acquisition chip architecture.

[0057] The data parsing module 100 synchronously receives discrete action signals of process equipment output from the upstream main control system via the industrial Ethernet protocol. These discrete action signals are digital trigger pulses representing instantaneous high-concentration exhaust gas emissions. When the upstream main control system outputs multiple discrete action signals from process equipment, the data parsing module 100 calls the corresponding empirical concentration calibration values ​​according to a preset mapping table between equipment numbers and empirical concentration calibration values. The equipment numbers range from 01 to 99, and the empirical concentration calibration values ​​range from 1000 mg / m³. 3 Up to 5000 mg / m 3 And within the same time step, perform maximum value selection or superposition calculation on multiple empirical concentration calibration values ​​to form the effective instantaneous concentration state quantity within the current time step;

[0058] Because conventional fluid concentration sensors are limited by the physical response lag due to the principles of gas adsorption and chemical reaction, the data analysis module 100 cannot obtain physical sensing signals that characterize the true components of the waste gas within the physical response lag time window of the conventional fluid concentration sensor. The physical response lag time window ranges from 2s to 5s. The data analysis module 100 uses a set time step as the execution cycle to cyclically scan and search the status register bits of the discrete action signals of the process equipment.

[0059] When a level transition occurs in the status register bit, the data parsing module 100 determines that there is a concentration change within the current time step interval. At this time, the data parsing module 100 discards the physical concentration sensing data that is in a hysteresis distortion state within the current period and calls the empirical concentration calibration value pre-written in the read-only memory as the instantaneous concentration state quantity within the current time step interval. Furthermore, from the moment of capturing the level transition, within the preset concentration holding time window, or during the period when the discrete action signal of the process equipment maintains an effective level, the preset concentration holding time window ranges from 10s to 30s.

[0060] The data parsing module 100 uses empirical concentration calibration values ​​as the effective instantaneous concentration state quantities within the corresponding time step to cover the operating conditions of high-concentration exhaust gas emissions for multiple sampling cycles. In actual industrial production environments, empirical concentration calibration values ​​are set based on the measured values ​​of volatile organic compound concentrations of the same production equipment under historical full-load operation conditions to ensure sufficient safety redundancy for subsequent thermodynamic calculations. When the status register bit remains at a zero level, the data parsing module 100 directly extracts the filtered value of the physical sensor signal as the instantaneous concentration state quantity within the current time step interval. The effective instantaneous concentration state determination logic of the data parsing module 100 within a discrete time step is expressed by a piecewise assignment function as follows:

[0061] ;

[0062] In the formula, For the data parsing module 100 in the first The effective instantaneous concentration state value determined within a discrete time step and uniformly converted into mass concentration; The time step sequence index is represented by a positive integer; The pre-set empirical concentration calibration value is based on statistical analysis of the production line's sewage discharge conditions; For the data parsing module 100 in the first Boolean state values ​​of discrete action signals of process equipment captured within a discrete time step; For the data acquisition unit in the first Physically sensed values ​​of volatile organic compound concentrations actually measured and transmitted within a discrete time step.

[0063] The data parsing module 100 allocates a specific random access memory address space at the end of each time step period, and packages the absolute timestamp of the current period, the calculated effective instantaneous concentration state value, and the synchronously acquired instantaneous flow state value of the exhaust gas into a single data structure; the continuous fluid is discretized at the data level and cut into virtual slices divided according to the time step. Each data structure strictly maps to the real exhaust gas entity with the corresponding physical spatial distance in the exhaust gas main pipe, thereby transforming the macroscopic fluid dynamics problem into a microscopic data queue update problem.

[0064] The data parsing module 100 sets an absolute timestamp, effective instantaneous concentration status value, exhaust gas instantaneous flow status value, gas mass volume, remaining distance to downstream switching valve group, and effective status word in the data structure. In each control cycle, it calculates the gas mass displacement based on the current exhaust gas instantaneous flow status value and the physical cross-sectional area of ​​the exhaust gas main pipe, and performs a decrement update on the remaining distance in each data structure. When the remaining distance is less than or equal to 0, the corresponding data structure is removed from the initial gas mass queue or marked as reached.

[0065] The data parsing module 100 writes the generated data structures into a pre-configured first-in-first-out queue in the order of their generation. By continuously executing the enqueue operation, an initial gas column reflecting the material distribution inside the exhaust gas manifold is established, thereby solving the problem of control time parameter lag caused by relying solely on physical sensors.

[0066] See attached document Figure 4 The mapping operation module 200 is configured as a floating-point arithmetic unit inside the industrial controller. The mapping operation module 200 continuously reads the initial gas column constructed by the data parsing module 100. The initial gas column records a continuously arranged data structure, which contains the instantaneous flow status value of the exhaust gas. Since the exhaust negative pressure of the exhaust fan at the back end of the production line fluctuates dynamically with the working conditions, the flow velocity of the exhaust gas in the exhaust gas main pipe exhibits nonlinear time-varying characteristics.

[0067] Since there is an objective time difference in the flow of harmful exhaust gas within a physical pipeline of a fixed length, the mapping calculation module 200 uses the time difference as a physical buffer window for the underlying hardware to extract the advance of control commands. The mapping calculation module 200 converts the fixed physical spatial distance into a dynamic early warning time parameter through a discrete integral algorithm.

[0068] The mapping operation module 200 extracts the physical length and physical cross-sectional area of ​​the exhaust gas main pipe between the pre-configured data acquisition unit and the downstream switching valve group in the physical memory; the physical cross-sectional area of ​​the exhaust gas main pipe is pre-calculated and entered by reading the pipe inner diameter dimension marked on the actual construction drawings at the industrial site.

[0069] Subsequently, a variable upper limit integral equation is established for each discrete gas mass in the initial gas mass column. The variable upper limit integral equation performs discrete accumulation operation on the instantaneous flow rate data with a set time step as the step unit until the displacement value obtained by discrete accumulation calculation is equal to the physical length of the exhaust gas main pipe between the data acquisition unit and the downstream switching valve group. When the integration interval involves future flow rate data after the current moment, the system uses the filtered instantaneous flow rate status value of the exhaust gas in the current control cycle, the moving average flow rate value of the most recent 3 to 5 control cycles, or the predicted flow rate value calculated by the main induced draft fan operating frequency and the pipeline resistance model as the future flow rate estimate to ensure that the calculation of the remaining transport time has executable data input.

[0070] To prevent the instantaneous exhaust gas flow rate from dropping to zero under extreme shutdown conditions, which could lead to a system dead loop, the mapping calculation module 200 establishes a safety check mechanism before performing discrete accumulation calculations. When the mapping calculation module 200 determines that the instantaneous exhaust gas flow rate is lower than the minimum sustaining flow rate threshold calibrated by the system, the minimum sustaining flow rate threshold is set to a value of 500 m³ / s.3 / h to 1000m 3 / h, forcibly interrupts the iteration of the variable upper limit integral equation and outputs the invalid status word of the corresponding discrete air mass; the mapping operation module 200 extracts the upper limit parameter of the integral when the trigger equation is true as the remaining transport time for the corresponding discrete air mass to reach the downstream switching valve group; for the discretized numerical approximation algorithm in the integral operation, it can be done according to the existing trapezoidal integral rule; the continuous domain mathematical expression for the variable upper limit integral operation performed by the mapping operation module 200 is:

[0071] ;

[0072] In the formula, The actual physical length of the exhaust gas main pipe between the data acquisition unit and the downstream switching valve group; The absolute timestamp for the current operation cycle executed by the mapping operation module 200; The remaining transport time for the discrete air mass output by the mapping operation module 200 to reach the downstream switching valve group is calculated. The instantaneous volumetric flow rate of the exhaust gas obtained by the mapping operation module 200 based on the integral time variable; This is the physical cross-sectional area of ​​the exhaust manifold; For time-independent variables in time integration operations.

[0073] Based on the remaining transport time, the mapping operation module 200 simultaneously evaluates the thermodynamic energy contained within the discrete air mass; the mapping operation module 200 reads the effective instantaneous concentration state value in the data structure and calculates the absolute mass of the target volatile organic compound contained in a single discrete air mass by combining it with the spatial volume parameters of the current discrete air mass.

[0074] When the effective instantaneous concentration state value is a mass concentration, the mapping calculation module 200 directly multiplies the mass concentration by the gas mass volume to obtain the absolute mass of the target volatile organic compound; when the effective instantaneous concentration state value is a volume fraction or molar concentration, the mapping calculation module 200 performs mass conversion based on the molecular weight, exhaust gas temperature, and exhaust gas pressure parameters of the target volatile organic compound before calculating the absolute mass; the mapping calculation module 200 retrieves the preset standard enthalpy constant of combustion of the target volatile organic compound and performs a multiplication operation between the absolute mass and the standard enthalpy constant of combustion.

[0075] The standard enthalpy constant of the target volatile organic compound is obtained by consulting a standard chemical thermodynamic parameter handbook and pre-stored in a non-volatile memory. The mapping operation module 200 maps the microscopic physical state parameters of a single discrete gas mass to the potential enthalpy of reaction released after entering the combustion chamber through multiplication operations. The potential enthalpy of reaction released after entering the combustion chamber provides a quantitative indicator for subsequent thermodynamic state changes. The mathematical expression for calculating the potential enthalpy of reaction by the mapping operation module 200 is as follows:

[0076] ;

[0077] In the formula, The mapping operation module 200 calculates the potential enthalpy of reaction for a single discrete gas mass. For the data parsing module 100 in the first The effective instantaneous concentration state value determined within a discrete time step and uniformly converted into mass concentration; For the data parsing module 100 in the first The instantaneous volumetric flow rate of the exhaust gas generated within a discrete time step; The time step sequence index is represented by a positive integer; This is a set time step constant; The standard enthalpy constant of combustion for the target volatile organic compound.

[0078] See attached document Figure 5 The asymmetric scheduling module 300 interacts with the mapping operation module 200. The asymmetric scheduling module 300 receives the remaining transport time and potential reaction enthalpy value output by the mapping operation module 200 in real time. The asymmetric scheduling module 300 is equipped with a comparator and a logic judgment unit. The comparator and logic judgment unit compare the potential reaction enthalpy value with the set safe heat load threshold. The set safe heat load threshold ranges from 1000MJ to 5000MJ. The remaining transport time is also compared with the system preparation time.

[0079] The safe heat load threshold is calculated based on the thermal stress limit parameters of the internal refractory material of the regenerative combustion equipment and the physical volume of the combustion chamber. In a specific implementation, the safe heat load threshold is set as the physical volume of the combustion chamber multiplied by the product of the difference between the highest withstand temperature of the refractory material and the current temperature and the specific heat capacity of air. This represents the maximum transient thermal energy impact that the regenerative combustion equipment can withstand without over-temperature interlock shutdown. The system preparation time is generated by adding the data transmission delay time of the control system network bus and the mechanical action response time of the pneumatic actuator of the switching valve group. The system preparation time ranges from 2s to 5s, representing the lower limit of the absolute time required for the underlying hardware to perform physical actions in response to control commands.

[0080] To eliminate the logical dead zone of the underlying algorithm at critical values, when the asymmetric scheduling module 300 determines that the potential reaction enthalpy is greater than or equal to the set safe heat load threshold and the remaining transport time is greater than or equal to the sum of the system preparation time and the planned extended exhaust cycle time, the asymmetric scheduling module 300 determines that the high-concentration exhaust gas mass will safely reach the downstream switching valve group after the regenerative combustion system is adjusted. Based on the secondary transport time between the downstream switching valve group and the combustion chamber, the expected time node for the high-concentration exhaust gas mass to enter the combustion chamber is further determined.

[0081] At this time, the asymmetric scheduling module 300 immediately triggers the asymmetric hot scheduling state, interrupting the symmetric isochronous switching logic that runs according to a fixed time cycle in the conventional control program; in the asymmetric hot scheduling state, the asymmetric scheduling module 300 outputs timing intervention instructions to the actuator driver of the underlying programmable logic controller; for the isochronous switching control process of the thermal regenerative combustion system under normal operating conditions, the existing timer cyclic triggering architecture can be used.

[0082] The timing intervention instruction is manifested as a dynamic overwrite of the set value of a specific countdown register inside the programmable logic controller; the asymmetric scheduling module 300 forcibly intervenes in the exhaust process of the target heat storage ceramic bed that is currently in a heat release state through the timing intervention instruction, extending the exhaust cycle time of the target heat storage ceramic bed.

[0083] The target thermal regenerative ceramic bed is determined by the asymmetric scheduling module 300 based on the current switching valve group status table and the order of the inlet, exhaust, and purging cycles of each thermal regenerative ceramic bed. The target thermal regenerative ceramic bed is the one that will switch to the inlet path after the high-concentration waste gas mass is expected to reach the downstream switching valve group, and is used to receive the thermal shock of this high-concentration waste gas mass. The extension of the exhaust cycle time is directly proportional to the difference between the potential enthalpy value and the set safe heat load threshold. The mathematical expression for calculating the actual exhaust cycle time of the target thermal regenerative ceramic bed by the asymmetric scheduling module 300 is as follows:

[0084] ;

[0085] In the formula, The actual exhaust cycle time of the target thermal regenerable ceramic bed is calculated and output by the asymmetric scheduling module 300. The rated exhaust cycle time set for a regenerative thermal combustion system under normal symmetrical operation; The time compensation gain coefficient is set in advance; The potential enthalpy of reaction of a single discrete gas mass is output from the mapping operation module 200 to the asymmetric scheduling module 300; The preset safe thermal load threshold is set for the asymmetric scheduling module 300.

[0086] To prevent the exhaust cycle time from being extended indefinitely, which could lead to overcooling or even internal flameout of the target regenerative ceramic bed, the asymmetric scheduling module 300 executes a limiting cutoff logic after calculating the actual exhaust cycle time. The limiting cutoff logic uses the minimum sustained temperature of the combustion chamber, the outlet temperature of the target regenerative ceramic bed, the minimum removal efficiency of volatile organic compounds, and the maximum allowable process cycle time as constraints. When any constraint reaches the preset boundary, the asymmetric scheduling module 300 stops extending the exhaust cycle time.

[0087] The asymmetric scheduling module 300 forces the actual exhaust cycle time to be constrained within the preset maximum allowable process cycle time boundary through the amplitude limiting cutoff logic. The maximum allowable process cycle time boundary is calibrated by experimental testing based on the physical decay curve of the lowest auto-ignition maintenance temperature of the combustion chamber. The test process records the critical time required for the internal temperature of the combustion chamber to drop to the ignition point of volatile organic compounds under different extended cycles, so as to ensure the absolute safety closed loop of the thermal conditions of the regenerative combustion system.

[0088] In the thermodynamic dimension, there is an objective temperature distribution curve along the gas flow direction inside the target heat storage ceramic bed; during the exhaust heat release cycle, the lower temperature purified gas enters the target heat storage ceramic bed from the bottom and exits from the top of the target heat storage ceramic bed into the combustion chamber. The purified gas continuously absorbs the heat contained inside the porous ceramic body as it flows through the porous ceramic body.

[0089] The asymmetric scheduling module 300 extends the exhaust cycle time of the target thermal storage ceramic bed, forcing a larger volume of low-temperature purified gas to flow through the porous ceramic body inside the target thermal storage ceramic bed, thereby forcibly stripping away the physical sensible heat accumulated inside the porous ceramic body. As a large amount of physical sensible heat inside the porous ceramic body is carried away, the longitudinal temperature gradient between the top and bottom of the target thermal storage ceramic bed is reduced accordingly. The asymmetric scheduling module 300 utilizes the asymmetric thermal scheduling state to pre-build a preset heat capacity receiving margin in the physical space, so that the target thermal storage ceramic bed has sufficient heat absorption capacity to buffer the excess heat released by the combustion of high-concentration exhaust gas when it subsequently switches to the intake state.

[0090] The asymmetric scheduling module 300 also corrects the switching time of the switching valve group based on the expected arrival time of the high-concentration exhaust gas mass, so that the time node of the target regenerative ceramic bed switching to the air intake state matches the time node of the high-concentration exhaust gas mass arriving at the downstream switching valve group. This ensures that the high-concentration exhaust gas mass enters the combustion chamber through the target regenerative ceramic bed with the temperature gradient reduced in advance, thereby avoiding the entire regenerative combustion system from triggering high-temperature protection shutdown due to heat accumulation that cannot be dissipated.

[0091] See attached document Figure 6The coupling operation module 400 is configured as an independent operation logic unit embedded within the industrial control system. The coupling operation module 400 maintains bidirectional data synchronous communication with the asymmetric scheduling module 300. When the asymmetric scheduling module 300 triggers the asymmetric thermal scheduling state, the coupling operation module 400 is synchronously activated to execute the underlying multiphysics coupling calculation task. The multiphysics coupling calculation task includes prediction calculation before the switching valve group action and feedback correction calculation after the switching valve group action. The prediction calculation is used to provide the inertia feedforward module 500 with the feedforward control input before the switching, and the feedback correction calculation is used to correct the temperature decay model and fluid resistance coefficient decay model of the subsequent control cycle.

[0092] The change in the thermodynamic state of the porous medium inside the thermal regenerating ceramic bed will lead to changes in fluid dynamic parameters. Since the dynamic viscosity of the gas is positively correlated with temperature, the decrease in temperature weakens the intensity of the thermal motion of gas molecules, thereby reducing the probability of momentum exchange between molecular layers. The extension of the exhaust cycle of the target thermal regenerating ceramic bed leads to an overall decrease in the temperature field inside the porous ceramic body of the target thermal regenerating ceramic bed, which in turn causes a nonlinear decrease in the viscous resistance of the exhaust gas flowing through the porous ceramic body of the target thermal regenerating ceramic bed. The basic thermodynamic property parameters required in the underlying calculation logic can be called according to the existing standard engineering thermophysics manual database.

[0093] The coupling calculation module 400 extracts the temperature drop parameters corresponding to the extension of the exhaust cycle of the target thermal storage ceramic bed. Specifically, the coupling calculation module 400 reads the reference temperature matrix of the thermocouple sensor array arranged longitudinally inside the target thermal storage ceramic bed at the end time of the rated exhaust cycle, and collects the current temperature matrix and temperature change rate of the thermocouple sensor array in real time during the extension of the exhaust cycle. Based on the current temperature matrix, temperature change rate, exhaust cycle extension amount and historical temperature decay curve, the final state temperature matrix of each calculation cycle during the extension of the exhaust cycle is predicted.

[0094] The coupling operation module 400 performs element-wise subtraction between the reference temperature matrix and the predicted final temperature matrix of the current calculation cycle to generate a dynamic longitudinal temperature gradient difference matrix. After the actual exhaust cycle ends, the coupling operation module 400 collects the real final temperature matrix and uses it to correct the historical temperature decay curve in the next control cycle. The coupling operation module 400 performs spatial weighted average calculation of the values ​​of each node in the dynamic longitudinal temperature gradient difference matrix along the longitudinal depth. The weight allocation rule of the spatial weighted average calculation is to assign a larger weight coefficient to the thermocouple sensor node closer to the bottom of the intake end to reflect the impact of the low temperature gas on the temperature field of the bottom porous medium in the early stage of entry.

[0095] The coupling operation module 400 defines the continuous output result of the spatial weighted average calculation as a temperature decrease parameter curve that is dynamically updated with the time series. To prevent calculation errors caused by the disconnection of the thermocouple sensor array and the resulting logic dead zone, the coupling operation module 400 determines whether the temperature acquisition value is within the effective range of 0℃ to 1200℃ before performing the subtraction operation. If the temperature acquisition value exceeds the effective range, it forcibly calls the pre-stored safety approximation constant to replace the actual temperature acquisition value. The safety approximation constant is dynamically assigned by extracting the average historical temperature readings of the corresponding thermocouple sensor in the first 5 normal operating cycles to maintain the physical continuity of the thermodynamic calculation.

[0096] After obtaining the temperature drop parameters, the coupled calculation module 400 inputs these parameters into a preset empirical formula for gas viscosity to solve for the corresponding transient dynamic viscosity value of the gas. The preset empirical formula for gas viscosity is constructed based on Sutherland's empirical law in fluid mechanics, and it converts macroscopic temperature changes into microscopic momentum transfer characteristics of gas molecule collisions. The continuous-domain mathematical expression for calculating the transient dynamic viscosity value by the coupled calculation module 400 is as follows:

[0097] ;

[0098] In the formula, The function that calculates and outputs the transient gas dynamic viscosity value as a function of the independent variable over time for the coupled calculation module 400; The independent variable representing absolute time; This is the dynamic viscosity constant of the reference gas at standard atmospheric pressure and reference temperature; For reference temperature constant; The Sutherland constant is related to the composition of the exhaust gas; The reference operating absolute temperature for the target thermal storage ceramic bed; This is a function of the temperature drop parameter extracted by the coupled operation module 400 as a function of the independent variable over time.

[0099] After calculating the transient dynamic viscosity value of the gas, the coupled calculation module 400 performs algebraic difference calculation on the transient dynamic viscosity value based on the principle of porous media fluid dynamics to generate the transient fluid resistance coefficient attenuation. The pressure drop of the fluid inside the porous ceramic body is dominated by viscous frictional resistance. The Eugen equation macroscopically equates the complex flow channels inside the porous medium to a large number of parallel capillaries, thus enabling the solution of pressure loss caused by fluid viscous shear stress under low Reynolds number laminar flow conditions.

[0100] The coupling operation module 400 retrieves the pre-calibrated porosity and equivalent particle diameter of the porous ceramic body, and uses the viscous resistance term of the classical Eugen equation in fluid mechanics to construct a fluid dynamics mapping relationship for the porous medium. It then calculates the instantaneous reduction in equivalent resistance caused by the decrease in gas viscosity to match the aerodynamic characteristics of the subsequent pipeline network.

[0101] When the bed Reynolds number calculated by the coupling calculation module 400 based on the exhaust gas velocity, exhaust gas density, transient gas dynamic viscosity, and equivalent particle diameter of the porous ceramic body is lower than the preset laminar flow threshold, the viscous drag term of the Eugen equation is used to calculate the fluid drag coefficient attenuation. When the bed Reynolds number is greater than or equal to the preset laminar flow threshold, the inertial drag term of the Eugen equation is further introduced to correct the fluid drag coefficient attenuation. To avoid overflow and crash of division operations with a denominator of 0 due to physical wear of the porous ceramic body porosity, the coupling calculation module 400 sets a lower limit constraint value of porosity of 0.1. The mathematical expression for the transient fluid drag coefficient attenuation generated by the coupling calculation module 400 through algebraic mapping operation is as follows:

[0102] ;

[0103] In the formula, The function of the transient fluid drag coefficient decay as a function of the time independent variable, calculated and output by the coupled computation module 400; Physical calibration of porosity for porous ceramic bodies; The equivalent particle diameter of the porous ceramic body; The dynamic viscosity constant of the reference gas at the reference operating absolute temperature; The effective filling height of the porous ceramic body inside the target thermal storage ceramic bed; To convert the linear resistance coefficient of laminar flow in porous media into an empirical quantization coefficient for a general quadratic resistance model of pipe networks; This is a function of the change of the transient gas dynamic viscosity value with time, calculated by the coupled computation module 400.

[0104] See attached document Figure 7 The inertia feedforward module 500 is configured as a microprocessor execution unit responsible for processing the aerodynamic fluctuations of the system. The inertia feedforward module 500 maintains a data link connection with the coupled calculation module 400 to obtain the attenuation of the fluid resistance coefficient. The exhaust gas transportation of the regenerative thermal incineration system relies on a high-power variable frequency induced draft fan. The impeller assembly of the high-power variable frequency induced draft fan has an objectively existing mechanical rotational inertia. Conventional proportional-integral-derivative feedback control logic objectively has a physical response lag when dealing with sudden changes in the fluid resistance coefficient.

[0105] When the fluid resistance inside the target heat storage ceramic bed decreases, if the high-power variable frequency induced draft fan maintains its original operating frequency, the instantaneous flow rate inside the pipeline network will fluctuate beyond the limit, thereby disrupting the micro-negative pressure balance state of the combustion chamber. For the deployment of the underlying code of the combustion chamber micro-negative pressure detection and conventional proportional-integral-derivative adjustment algorithm, it can be based on the existing standard function blocks of the programmable logic controller.

[0106] The inertia feedforward module 500 converts the fluid resistance coefficient attenuation into the total system pressure compensation required by the pipeline network. According to the fluid dynamics pipeline network characteristic theory, the pressure loss of fluid in a closed pipeline due to friction and local components is directly proportional to the square of the mass flow rate. The inertia feedforward module 500 retrieves the real-time measured instantaneous mass flow rate and density parameters of the exhaust gas.

[0107] Based on the fluid dynamics resistance characteristic equation that the pipeline resistance is proportional to the square of the flow rate, the fluid resistance coefficient attenuation is mapped to the system pressure regulation benchmark. To prevent high-frequency noise interference from causing pressure control benchmark oscillations, the inertia feedforward module 500 uses a first-order low-pass filter algorithm to smooth the system pressure regulation benchmark. The time constant of the first-order low-pass filter algorithm is set between 0.5s and 2.0s to filter out high-frequency airflow pulsations caused by the rotation of the fan blades. The time constant of the first-order low-pass filter algorithm is determined by collecting the background noise spectrum of the high-power variable frequency induced draft fan exhaust port pressure transmitter under no-load conditions and taking the reciprocal of the first-order dominant frequency. The mathematical expression for calculating the system total pressure compensation by the inertia feedforward module 500 is as follows:

[0108] ;

[0109] In the formula, The total pressure compensation of the system, calculated and output by the inertia feedforward module 500, is a function of the time-dependent independent variable. The independent variable representing absolute time; The transient fluid drag coefficient attenuation function is input from the coupling calculation module 400 to the inertia feedforward module 500. It is a function of the instantaneous mass flow rate of exhaust gas as a function of the independent variable over time, which is measured in real time. This is the exhaust gas density parameter calculated in real time based on the absolute temperature and absolute pressure of the exhaust gas.

[0110] After acquiring the total pressure compensation of the system, the inertia feedforward module 500 combines the mechanical rotational inertia of the high-power variable frequency induced draft fan to generate a feedforward intervention frequency command. The inertia feedforward module 500 extracts the pre-set physical parameters of the number of pole pairs and rated speed of the high-power variable frequency induced draft fan motor from the physical memory, and establishes a nonlinear transfer function between the pressure change and the speed change based on the fan proportional law. When the fluid resistance inside the target thermal storage ceramic bed decreases, the inertia feedforward module 500 converts the total pressure compensation of the system into a negative frequency correction or a negative torque correction to reduce the output energy of the main induced draft fan in advance and avoid the instantaneous flow rate of the pipeline network from surging due to the decrease in resistance.

[0111] When a high-power variable frequency induced draft fan performs a speed reduction action, it needs to overcome the mechanical rotational inertia of the impeller assembly. The inertia feedforward module 500 converts the mechanical rotational inertia into a time-dimensional compensation derivative term based on the rotational motion pattern of Newton's second law, and introduces an engineering conversion coefficient to balance the physical dimensions. The engineering conversion coefficient ranges from 0.1 to 0.5, and then the compensation derivative term is superimposed on the basic speed adjustment to form a dynamic feedforward control sequence.

[0112] To prevent excessive compensation under extreme disturbances from causing a negative dead zone in the square root calculation and triggering system failure, the inertia feedforward module 500 forcibly checks the radicand value in the formula before performing the calculation. If the absolute value of the reference total pressure minus the system total pressure compensation is less than 0, the entire radicand term will be forcibly assigned the minimum stable operating total pressure constant allowed by the system, rather than truncating the system total pressure compensation itself, in order to maintain the legality of the mathematical domain and the minimum system ventilation volume. The mechanical rotational inertia value extracted by the inertia feedforward module 500 is pre-written into the read-only storage area based on the three-dimensional structural simulation rotor dynamics analysis report provided by the high-power variable frequency induced draft fan supplier. The continuous domain mathematical expression for the feedforward intervention frequency command calculated by the inertia feedforward module 500 is as follows:

[0113] ;

[0114] In the formula, The function of the feedforward intervention frequency command output by the inertia feedforward module 500 to the high-power variable frequency induced draft fan driver as a function of the time independent variable; The independent variable representing absolute time; The number of pole pairs for a high-power variable frequency induced draft fan motor; The reference operating speed of the high-power variable frequency induced draft fan before the sudden change in fluid resistance occurs; This is the baseline total pressure value inside the pipeline network before the sudden change in fluid resistance occurs; The total pressure compensation of the system calculated by the inertia feedforward module 500 is a function of the time-dependent independent variable. These are the factory-issued aerodynamic characteristic constants for high-power variable frequency induced draft fans; The engineering conversion factor is used to map torque dynamic parameters to equivalent speed corrections; The mechanical rotational inertia of the impeller assembly of a high-power variable frequency induced draft fan; This refers to the rated electromagnetic torque of the high-power variable frequency induced draft fan motor.

[0115] The inertia feedforward module 500 sends the feedforward intervention frequency command directly to the underlying hardware driver of the high-power variable frequency induced draft fan via the industrial communication bus. After receiving the feedforward intervention frequency command, the underlying hardware driver adjusts the motor output through the frequency control loop or torque control loop inside the inverter. The feedforward intervention frequency command is used as the feedforward superposition amount, limiting correction amount or priority control setpoint of the output of the conventional proportional integral derivative controller to participate in the inverter control calculation.

[0116] Because the feedforward intervention frequency command includes a number of advanced calculation steps, the high-power variable frequency induced draft fan can execute torque unloading and speed reduction actions in advance at the synchronous physical instant when the temperature field of the porous medium inside the target heat storage ceramic bed is substantially reduced, causing resistance attenuation; the inertia feedforward module 500 uses the transmission time difference of the physical causal relationship to offset the inherent mechanical response lag of the high-power variable frequency induced draft fan, ensuring that the heat storage combustion system always maintains a constant combustion chamber micro-negative pressure boundary condition under asymmetric thermal scheduling, thereby cutting off the physical diffusion path of harmful gases leaking back into the upstream production line environment.

[0117] To aid in understanding the technical solution of this invention, a specific application example of a waste gas treatment system for a lithium battery electrode coating production line is provided below.

[0118] The lithium battery electrode coating production line continuously emits volatile organic waste gas containing N-methylpyrrolidone during operation. When the coating machine is changing the electrode roll or cleaning the equipment, the upstream main control system triggers the venting action. The waste gas in the exhaust pipe accumulates a concentration far exceeding the normal operating concentration in a short period of time, forming a high-concentration gas cloud.

[0119] The data parsing module 100 operates with a time step of 0.2s. When the data parsing module 100 receives the discrete action signal of the process equipment output by the upstream main control system, it determines that a sudden change in the operating condition has occurred, discards the conventional physical concentration sensor data with physical response lag, calls the preset empirical concentration calibration value, and packages the empirical concentration calibration value and the instantaneous flow status value of the exhaust gas into the initial gas flow column.

[0120] The mapping calculation module 200 reads the initial gas mass data and performs variable upper limit integral calculation based on the physical length and cross-sectional area of ​​the exhaust gas main. The system calculates that the remaining transport time for the high-concentration gas mass to reach the downstream switching valve group is 12.4s. At the same time, the mapping calculation module 200, combined with the standard combustion enthalpy constant of N-methylpyrrolidone, calculates that the potential reaction enthalpy of the high-concentration gas mass entering the combustion chamber reaches 4850MJ.

[0121] The asymmetric scheduling module 300 compares the potential enthalpy of reaction of 4850MJ with the set safe heat load threshold of 3500MJ and determines that there is a risk of overheating. Since the remaining transport time of 12.4s is greater than the system preparation time, the asymmetric scheduling module 300 outputs a timing intervention command to the underlying programmable logic controller, forcibly extending the exhaust cycle time of the target heat storage ceramic bed, which was originally in the exothermic state, from the conventionally set 90s to 135s. During the extended exhaust cycle, the low-temperature purified gas continuously flows through the porous ceramic body inside the target heat storage ceramic bed and carries away the physical sensible heat, causing the longitudinal temperature gradient between the top and bottom of the target heat storage ceramic bed to decrease.

[0122] The coupled calculation module 400 calculates the temperature drop parameters caused by the extension of the exhaust cycle, substitutes the temperature drop parameters into the preset empirical formula for gas viscosity to obtain the transient dynamic viscosity value of the gas, and then generates the transient fluid resistance coefficient attenuation of the target thermal regenerator ceramic bed through the principle of porous media fluid dynamics.

[0123] The inertia feedforward module 500 calculates the total pressure compensation of the system based on the attenuation of the transient fluid resistance coefficient. 1.5 seconds before the switching valve group actuates, the inertia feedforward module 500 generates a feedforward intervention frequency command in combination with the mechanical rotational inertia of the main induced draft fan impeller assembly, and outputs the feedforward intervention frequency command to the inverter of the main induced draft fan. The main induced draft fan performs a frequency reduction torque unloading action to offset the sudden change in pipeline fluid resistance caused by the switching valve group actuation.

[0124] Table 1: Comparison of operating data between conventional isochronous control and the asymmetric scheduling and feedforward coupling control of the present invention under the condition of sudden change in exhaust gas concentration.

[0125] According to Table 1 and Figure 8 It can be seen that the exhaust gas flow rate remains at 30100 m³ / s from 10.0 s to 14.5 s. 3 / h to 30321.7m 3 In the / h range, the exhaust gas concentration decreased from 1521.4 mg / m³. 3 The concentration suddenly increased to 8122.5 mg / m³. 3 This leads to abrupt changes in thermal load and fluid dynamic boundary conditions.

[0126] The conventional control strategy operates on a fixed cycle. The average temperature of the target regenerative ceramic bed remains above 815℃ from 0.0s to 14.5s. At 15.0s, the switching valve group activates, and the temperature reaches 8095.1 mg / m³. 3 After the exhaust gas enters, due to the failure to release the sensible heat inside the porous ceramic body in advance, the temperature at the center of the combustion chamber rises to 1063.4℃ in 20.0s, exceeding the safety boundary of the refractory material. At the same time, conventional feedback control cannot overcome the mechanical rotational inertia of the main induced draft fan to reduce its speed in advance. At 15.0s, the total pressure in the combustion chamber jumps from -121.3Pa to +24.8Pa during the instantaneous resistance decay, and at 16.5s, a positive pressure overflow of +78.6Pa occurs.

[0127] Under the same test conditions, the average temperature of the target regenerative ceramic bed decreased continuously from 816.3℃ to 684.5℃ from 0.0s to 14.5s, thus pre-establishing a heat capacity receiving margin, reaching 8088.2 mg / m³ at 15.0s. 3 After the exhaust gas enters the combustion chamber, the center temperature of the combustion chamber only rises to 938.2℃ in 20.0s, remaining within the safe thermodynamic range. In terms of pressure control, the present invention outputs a feedforward command to reduce speed at 14.5s in advance, and the total pressure of the combustion chamber drops to -135.2Pa. When the valve group operates at 15.0s, the fan output pressure head decreases and the pipeline resistance decays in time, achieving time synchronization. From 15.0s to 16.5s, the total pressure stabilizes between -74.5Pa and -65.2Pa. Experimental data confirms that the present invention can maintain the system's thermohydraulic stability when dealing with high-concentration exhaust gas impacts.

[0128] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An industrial hazardous waste gas pretreatment and regenerative thermal incineration system, characterized in that, The system includes: The data parsing module is used to acquire physical sensor signals and discrete action signals of process equipment, perform processing according to the set time step, and establish an initial gas flow column containing effective instantaneous concentration state values ​​and instantaneous flow state values ​​of exhaust gas. The mapping operation module is used to read the initial gas column, perform variable upper limit integration operation to calculate the remaining transport time to the downstream switching valve group, and calculate the potential reaction enthalpy value in combination with the standard combustion heat enthalpy constant of the target volatile organic compound. The asymmetric scheduling module is used to output a timing intervention command to the downstream switching valve group to extend the exhaust cycle time of the target thermal storage ceramic bed when the potential reaction enthalpy value is greater than the set safe heat load threshold and the remaining transport time meets the set conditions. The coupled calculation module is used to extract the temperature drop parameters corresponding to the extension of the exhaust cycle time of the target thermal regenerator ceramic bed, solve the transient gas dynamic viscosity value, and generate the transient fluid resistance coefficient attenuation amount; The inertia feedforward module is used to calculate the total pressure compensation of the system based on the attenuation of the transient fluid resistance coefficient, generate feedforward control commands in combination with the rotational inertia constant of the main induced draft fan, and output them to the main induced draft fan frequency converter before the downstream switching valve group is activated.

2. The industrial hazardous waste gas pretreatment and regenerative thermal incineration system according to claim 1, characterized in that, The data analysis module has a built-in concentration state determination logic. When the discrete action signal of the process equipment undergoes a level transition, the data analysis module calls a preset empirical concentration calibration value as the effective instantaneous concentration state value within the corresponding time step within a preset concentration holding time window. When the discrete action signal of the process equipment remains at a zero level, the data analysis module calls the physical sensing value of the physical sensing signal as the effective instantaneous concentration state value, thereby covering the physical response hysteresis time window of conventional fluid concentration sensors.

3. The industrial hazardous waste gas pretreatment and regenerative thermal incineration system according to claim 1, characterized in that, The data parsing module is specifically used to encapsulate the absolute timestamp, the effective instantaneous concentration state value, and the instantaneous flow rate state value of the exhaust gas into a single data structure within each set time step, and allocate the remaining distance from the downstream switching valve group in the single data structure; and within each control cycle, calculate the gas mass displacement based on the division operation value of the instantaneous flow rate state value of the exhaust gas and the physical cross-sectional area of ​​the exhaust gas main pipe, perform a decremental update on the remaining distance in the single data structure, and establish the initial gas mass queue characterizing the spatial material distribution by continuously executing enqueue operations.

4. The industrial hazardous waste gas pretreatment and regenerative thermal incineration system according to claim 1, characterized in that, The mapping operation module is specifically used to establish a variable upper limit integral equation. The variable upper limit integral equation uses the ratio of the instantaneous flow rate of the exhaust gas to the physical cross-sectional area of ​​the exhaust gas main pipe as the integrand to perform discrete accumulation operation. When the accumulated displacement value obtained by discrete accumulation calculation is equal to the physical length of the exhaust gas main pipe between the data acquisition unit and the downstream switching valve group, the upper limit parameter of the integral when the trigger equation is true is extracted, and the upper limit parameter of the integral is used as the remaining transport time for the corresponding discrete gas mass to reach the downstream switching valve group.

5. The industrial hazardous waste gas pretreatment and regenerative thermal incineration system according to claim 1, characterized in that, The mapping operation module is pre-set with the standard enthalpy constant of the target volatile organic compound and the set time step constant. Specifically, the mapping operation module is used to perform a sequential multiplication operation on the effective instantaneous concentration state value, the instantaneous flow rate state value of the exhaust gas, the set time step constant, and the standard enthalpy constant of the target volatile organic compound, and the product obtained by the sequential multiplication operation is used as the potential reaction enthalpy value released after the corresponding discrete gas mass enters the combustion chamber.

6. The industrial hazardous waste gas pretreatment and regenerative thermal incineration system according to claim 1, characterized in that, The specific setting condition is that the remaining transport time is greater than or equal to the sum of the system preparation time and the planned extended exhaust cycle time of the target regenerative ceramic bed; the asymmetric scheduling module is specifically used to calculate the difference between the potential reaction enthalpy and the set safe heat load threshold, multiply the difference by the set time compensation gain coefficient and then add it to the rated exhaust cycle time to obtain the actual exhaust cycle time, and use the amplitude limiting cutoff logic to forcibly constrain the actual exhaust cycle time within the preset maximum process allowable cycle time boundary.

7. The industrial hazardous waste gas pretreatment and regenerative thermal incineration system according to claim 1, characterized in that, The coupling operation module stores a reference gas dynamic viscosity constant, a reference temperature constant, and a Sutherland constant related to the waste gas components. Specifically, the coupling operation module is used to subtract the temperature drop parameter from the reference operating absolute temperature of the target regenerative ceramic bed to obtain the actual operating absolute temperature. Using the reference gas dynamic viscosity constant, the reference temperature constant, the Sutherland constant, and the actual operating absolute temperature, the module performs algebraic operations based on the Sutherland empirical law formula to generate the transient gas dynamic viscosity value.

8. The industrial hazardous waste gas pretreatment and regenerative thermal incineration system according to claim 1, characterized in that, The coupling operation module is specifically used to extract the dynamic viscosity constant of the reference gas at the reference operating absolute temperature, calculate the difference between the dynamic viscosity constant of the reference gas and the dynamic viscosity value of the transient gas, and combine the effective filling height of the porous ceramic body, the physical calibration porosity of the porous ceramic body, the equivalent particle diameter of the porous ceramic body, and the empirical equivalence coefficient to perform an algebraic mapping operation on the difference between the dynamic viscosity constant of the reference gas and the dynamic viscosity value of the transient gas according to the viscous resistance term of the Eugen equation to obtain the attenuation of the transient fluid resistance coefficient.

9. The industrial hazardous waste gas pretreatment and regenerative thermal incineration system according to claim 1, characterized in that, The inertia feedforward module is specifically used to smooth the real-time measured instantaneous mass flow rate of the exhaust gas using a first-order low-pass filtering algorithm, obtain the exhaust gas density parameter, divide the square of the smoothed instantaneous mass flow rate of the exhaust gas by twice the exhaust gas density parameter, and multiply the result by the transient fluid resistance coefficient attenuation to generate the system total pressure compensation.

10. The industrial hazardous waste gas pretreatment and regenerative thermal incineration system according to claim 9, characterized in that, The feedforward control command is specifically a feedforward intervention frequency command; the inertia feedforward module is specifically used to obtain the reference total pressure value and reference operating speed before the fluid resistance change occurs, divide the difference between the reference total pressure value and the system total pressure compensation amount by the factory aerodynamic characteristic constant and perform square root operation to generate the basic speed adjustment amount; The system's total pressure compensation is used to perform a derivative operation with respect to absolute time to generate a compensation derivative term. The compensation derivative term, the moment of inertia constant of the main induced draft fan, and the engineering conversion coefficient are multiplied together and then divided by the rated electromagnetic torque of the main induced draft fan motor to generate an equivalent speed correction. The reference operating speed, the basic speed adjustment, and the equivalent speed correction are subtracted sequentially, and the result of the subtraction is multiplied by the ratio of the number of pole pairs of the motor to the constant to generate the feedforward intervention frequency command output to the main induced draft fan inverter.

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