Online control system and method for tetramethylammonium hydroxide production equipment

Abstract

The invention discloses an online control system and method for tetramethylammonium hydroxide production equipment, and belongs to the technical field of production equipment control, and the method specifically comprises the following steps: collecting key parameters in the tetramethylammonium hydroxide production equipment in real time, and preprocessing the collected key parameters in the tetramethylammonium hydroxide production equipment, a tetramethylammonium hydroxide production process model is established, key parameters in the tetramethylammonium hydroxide production process are monitored in real time, model parameters of the tetramethylammonium hydroxide production process model are optimized and updated in real time, production equipment of tetramethylammonium hydroxide is controlled, and a self-adaptive adjustment mechanism is utilized to adjust the production process of tetramethylammonium hydroxide. Control parameters are automatically corrected according to fluctuation of environment and reaction conditions, an alarm system is arranged, when the parameters exceed a set threshold value, alarm is triggered, and the corresponding control parameters are automatically adjusted through a self-adaptive adjustment mechanism; the method can cope with environmental fluctuation, improve the reaction conversion rate, reduce the production cost and greatly reduce the dependence on manual operation.

Description

Technical Field

[0001] The invention belongs to the technical field of production equipment control, in particular to an online control system and method for tetramethylammonium hydroxide production equipment. Background Art

[0002] Tetramethylammonium hydroxide (TMAH) is an important chemical reagent, widely used in semiconductor manufacturing, photoresist removal, chemical mechanical polishing (CMP), organic synthesis and other fields. In the semiconductor industry, the high purity requirement of TMAH is particularly important, and it is usually required to meet the electronic grade (ELGrade) standard to avoid the impact of impurities on the performance of semiconductor devices. In addition, TMAH is also highly alkaline and highly toxic, and its production parameters and operating conditions must be strictly controlled during the production process.

[0003] The following technical difficulties exist in the production process of tetramethylammonium hydroxide: 1) Complexity of reaction parameters: reaction rate and equilibrium are affected by multiple factors such as temperature, pressure, and reactant concentration; 2) Insufficient real-time monitoring and regulation: Real-time monitoring and rapid feedback cannot be achieved, resulting in delayed reaction control, reduced production efficiency and quality stability; 3) High-precision control requirements: Existing technologies are difficult to balance precision and flexibility; 4) By-products and safety hazards: NaCl by-products generated by the reaction may accumulate, affecting reaction efficiency.

[0004] Current online control methods are usually based on simple closed-loop control (such as PID control) and single parameter adjustment. These methods have the following shortcomings: 1) Lack of processing capabilities for multi-variable coupling effects, unable to cope with dynamically changing complex production environments; 2) Inaccurate reaction models, making it difficult to achieve precise control of nonlinear, dynamically changing systems; 3) Traditional systems have a slow response speed, making it difficult to meet the needs of rapid adjustments; 4) Equipment lacks adaptive capabilities, making it difficult to maintain stable operation in the face of environmental fluctuations (such as temperature changes or raw material concentration fluctuations).

[0005] The TMAH production process urgently needs to integrate more intelligent, precise and real-time online control methods to comprehensively improve production efficiency, product quality and safety. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention proposes an online control system and method for tetramethylammonium hydroxide production equipment, which realizes all-round and precise control of the production process by integrating multivariable feedback control, model predictive control, real-time parameter optimization and adaptive adjustment mechanism.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] An online control method for tetramethylammonium hydroxide production equipment, comprising:

[0009] Real-time collection of key parameters in the tetramethylammonium hydroxide production equipment, including: the generation rate of tetramethylammonium hydroxide, the mass transfer rate of sodium hydroxide, and the concentrations of sodium hydroxide and tetramethylammonium chloride, and pre-processing of the collected key parameters in the tetramethylammonium hydroxide production equipment;

[0010] Establish a tetramethylammonium hydroxide production process model and conduct real-time monitoring of key parameters in the tetramethylammonium hydroxide production process;

[0011] Real-time optimization and update of model parameters of tetramethylammonium hydroxide production process model, and control of tetramethylammonium hydroxide production equipment;

[0012] Utilizes an adaptive adjustment mechanism to automatically correct control parameters based on fluctuations in environmental and reaction conditions;

[0013] Set up an alarm system to trigger an alarm when the parameters exceed the set threshold, and automatically adjust the corresponding control parameters through an adaptive adjustment mechanism.

[0014] Specifically, the tetramethylammonium hydroxide production process model is established to monitor the key parameters in the tetramethylammonium hydroxide production process in real time, including:

[0015] Sodium hydroxide and tetramethylammonium chloride are used as reactants to generate tetramethylammonium hydroxide. The generation rate of tetramethylammonium hydroxide is assumed to be proportional to the concentration of sodium hydroxide and tetramethylammonium chloride. The generation rate of tetramethylammonium hydroxide is calculated as follows:

[0016] ,

[0017] in, represents the generation rate of tetramethylammonium hydroxide, C TMAH represents the concentration of tetramethylammonium hydroxide, t represents the time, C NaOH Indicates the concentration of sodium hydroxide, C TMA-Cl represents the concentration of tetramethylammonium chloride, k represents the reaction rate constant, r(C TMAH ) represents the loss rate function;

[0018] Assuming sodium hydroxide as a substance controlled by mass transfer, a mass transfer rate model is established. The specific formula is:

[0019] ,

[0020] Among them, N NaOHrepresents the mass transfer rate model, that is, the mass transfer rate of sodium hydroxide, k L represents the liquid film mass transfer coefficient, a represents the phase interface area, C NaOH,bulk represents the concentration of sodium hydroxide in the bulk phase, C NaOH,inter represents the concentration of sodium hydroxide in the interfacial phase;

[0021] In the production process of tetramethylammonium hydroxide, temperature changes will occur. A thermal balance model is established. The specific formula is:

[0022] ,

[0023] in, represents the thermal equilibrium model, that is, the change of temperature, T represents the reaction temperature, Q react represents the heat released by the reaction, Q cool Indicates the heat removed by the cooling system, C p represents the specific heat capacity of the reaction solution, and m represents the mass of the reaction solution.

[0024] Specifically, the real-time optimization and updating of the model parameters of the tetramethylammonium hydroxide production process model to control the production equipment of tetramethylammonium hydroxide includes:

[0025] Assume that the state variable of the tetramethylammonium hydroxide production equipment at time t is X(t), and the input variable is U(t). , CT MAH (t) represents the concentration of tetramethylammonium hydroxide at time t, C NaOH (t) represents the concentration of sodium hydroxide at time t, C TMA-Cl (t) represents the concentration of tetramethylammonium chloride at time t, T(t) represents the reaction temperature at time t, zz represents the transpose of a vector or matrix, , F NaOH (t) represents the flow rate of sodium hydroxide at time t, P heater (t) represents the power of the heater of the production equipment of tetramethylammonium hydroxide;

[0026] A nonlinear state space model of tetramethylammonium hydroxide production equipment is established. The specific formula is: , Represents the nonlinear state-space model of a tetramethylammonium hydroxide production plant, represents the time-varying parameter;

[0027] Step S303: Future The state of the time step is predicted for the future time t+ , the state prediction model formula of tetramethylammonium hydroxide production equipment is:

[0028] ,

[0029] in, represents the state prediction model of tetramethylammonium hydroxide production equipment, that is, the future time t+ Status of the tetramethylammonium hydroxide production facility.

[0030] Specifically, the real-time optimization and updating of the model parameters of the tetramethylammonium hydroxide production process model to control the production equipment of tetramethylammonium hydroxide also includes:

[0031] Set the objective function to solve the state prediction model of tetramethylammonium hydroxide production equipment and obtain the predicted state X of tetramethylammonium hydroxide production equipment. yc , the specific formula of the objective function is:

[0032] ,

[0033] Among them, J represents the objective function, min represents the minimization function, Qs represents the state error weighting matrix, R represents the control input weighting matrix, X target It represents the desired target state, which usually has requirements such as product quality and output, and N represents the number of prediction steps.

[0034] Specifically, the adaptive adjustment mechanism is used to automatically correct the control parameters according to the fluctuations of the environment and reaction conditions, including:

[0035] The objective function of the adaptive adjustment mechanism of tetramethylammonium hydroxide production equipment is set as follows:

[0036] ,

[0037] in, represents the objective function of the adaptive adjustment mechanism of tetramethylammonium hydroxide production equipment, X sj (t) represents the actual output value of the tetramethylammonium hydroxide production equipment, represents the observation vector at time t, represents the parameter vector of the tetramethylammonium hydroxide production facility, represents the weight value at time t, and Ts represents the total number of moments;

[0038] Minimize the objective function of the adaptive adjustment mechanism of the tetramethylammonium hydroxide production equipment and obtain the optimal parameter estimation of the tetramethylammonium hydroxide production equipment. The specific formula is:

[0039] ,

[0040] in, represents the optimal parameter estimation of tetramethylammonium hydroxide production equipment;

[0041] According to the obtained optimal parameters of tetramethylammonium hydroxide production equipment, it is estimated , real-time control of tetramethylammonium hydroxide production equipment.

[0042] Specifically, the key parameters in the tetramethylammonium hydroxide production equipment include: temperature, pH, concentration and liquid level parameters.

[0043] Specifically, the preprocessing includes: sensor calibration, data cleaning and data smoothing;

[0044] The sensor calibration uses a set correction factor to correct the reading of each sensor;

[0045] The data cleaning removes redundant and duplicate data;

[0046] The data smoothing process uses a sliding average method to smooth the real-time data.

[0047] An online control system for tetramethylammonium hydroxide production equipment, used to implement an online control method for tetramethylammonium hydroxide production equipment, comprising: a data acquisition module, a modeling monitoring module, an optimization control module, an adaptive adjustment module and an early warning module;

[0048] The data acquisition module is used to collect key parameters in the tetramethylammonium hydroxide production equipment in real time, including: the generation rate of tetramethylammonium hydroxide, the mass transfer rate of sodium hydroxide and the concentrations of sodium hydroxide and tetramethylammonium chloride, and pre-process the collected key numbers in the tetramethylammonium hydroxide production equipment;

[0049] The modeling and monitoring module is used to establish a tetramethylammonium hydroxide production process model and to monitor key parameters in the tetramethylammonium hydroxide production process in real time;

[0050] The optimization control module is used to optimize and update the model parameters of the tetramethylammonium hydroxide production process model in real time and control the production equipment of tetramethylammonium hydroxide;

[0051] The adaptive adjustment module is used to automatically correct the control parameters according to the fluctuations of the environment and reaction conditions by using the adaptive adjustment mechanism;

[0052] The early warning module is used to set up an alarm system, trigger an alarm when a parameter exceeds a set threshold, and automatically adjust the corresponding control parameters through an adaptive adjustment mechanism.

[0053] Specifically, the optimization control module includes: a space model building unit, a state prediction model building unit and a prediction state solving unit;

[0054] The space model building unit is used to build a nonlinear state space model of a tetramethylammonium hydroxide production device;

[0055] The state prediction model establishing unit is used to establish a state prediction model of tetramethylammonium hydroxide production equipment;

[0056] The predicted state solving unit is used to solve the state prediction model of the tetramethylammonium hydroxide production equipment to obtain the predicted state of the tetramethylammonium hydroxide production equipment.

[0057] Specifically, the adaptive adjustment module includes: an adaptive function setting unit and an optimal parameter estimation unit;

[0058] The adaptive function setting unit is used to set the objective function of the adaptive adjustment mechanism of the tetramethylammonium hydroxide production equipment;

[0059] The optimal parameter estimation unit is used to minimize the objective function of the self-adaptive adjustment mechanism of the tetramethylammonium hydroxide production equipment to obtain the optimal parameter estimation of the tetramethylammonium hydroxide production equipment.

[0060] Compared with the prior art, the present invention has the following beneficial effects:

[0061] 1. The present invention provides an online control method for tetramethylammonium hydroxide production equipment, which realizes real-time monitoring and optimization control of key parameters such as temperature, reactant concentration, pH value, etc. in the TMAH production process, ensures that the reaction conditions are always in the optimal state, reduces impurity generation through precise ratio control and by-product suppression mechanism, and improves the purity and stability of the product.

[0062] 2. The present invention proposes an online control method for tetramethylammonium hydroxide production equipment. According to the reaction kinetics model and the mass transfer and heat transfer model, the future system state is predicted and the control input is adjusted in advance, the reactant feeding rate is optimized in real time, the raw material waste is reduced, the reaction conversion rate is improved, and the production cost is reduced.

[0063] 3. The present invention proposes an online control method for tetramethylammonium hydroxide production equipment, introduces an adaptive adjustment mechanism, and can cope with environmental fluctuations, maintain stable operation of the system, and greatly reduce dependence on manual operation by dynamically updating control parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 A flow chart of an online control method for tetramethylammonium hydroxide production equipment provided by the present invention;

[0065] Figure 2 The adaptive control flow chart provided by the present invention;

[0066] Figure 3 This is an architecture diagram of an online control system for tetramethylammonium hydroxide production equipment provided by the present invention. DETAILED DESCRIPTION

[0067] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, in the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "No. 1", "No. 2" and "No. 3" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. The present invention is further explained below in conjunction with specific embodiments.

[0068] Example 1 See also Figure 1-2 , an embodiment provided by the present invention: an online control method for tetramethylammonium hydroxide production equipment, comprising the following specific steps:

[0069] Step S1: collecting key parameters in the tetramethylammonium hydroxide production equipment in real time, including the generation rate of tetramethylammonium hydroxide, the mass transfer rate of sodium hydroxide, and the concentrations, temperature, pH, concentration and liquid level of sodium hydroxide and tetramethylammonium chloride, and preprocessing the collected key parameters in the tetramethylammonium hydroxide production equipment;

[0070] Temperature sensor detection: set the optimal reaction temperature range and collect reaction temperature data in real time through the temperature sensor. pH value detection: monitor the solution pH value in real time through the online pH sensor. Concentration monitoring: use conductivity sensor or spectrophotometry to detect the concentration of tetramethylammonium hydroxide. Liquid level monitoring: use liquid level sensor to detect the reactor liquid level in real time to ensure sufficient supply of reactants.

[0071] The preprocessing includes: sensor calibration, data cleaning and data smoothing;

[0072] The sensor calibration uses a set correction factor to correct the reading of each sensor;

[0073] The data cleaning removes redundant and duplicate data;

[0074] The data smoothing process uses a sliding average method to smooth the real-time data in order to reduce interference;

[0075] Step S2: establishing a tetramethylammonium hydroxide production process model, and performing real-time monitoring of key parameters in the tetramethylammonium hydroxide production process;

[0076] The core reaction equation in the production process of tetramethylammonium hydroxide (TMAH) is:

[0077] , the reaction is a first order reaction, NaOH and tetramethylammonium chloride (TMA-Cl) are used as reactants to generate tetramethylammonium hydroxide (TMAH) and NaCl;

[0078] The specific steps of step S2 are:

[0079] Step S201: Sodium hydroxide and tetramethylammonium chloride are used as reactants to generate tetramethylammonium hydroxide. The generation rate of tetramethylammonium hydroxide is set to be proportional to the concentration of sodium hydroxide and tetramethylammonium chloride. The generation rate of tetramethylammonium hydroxide is calculated. The specific formula is:

[0080] ,

[0081] in, represents the generation rate of tetramethylammonium hydroxide, C TMAH represents the concentration of tetramethylammonium hydroxide, t represents the time, C NaOH Indicates the concentration of sodium hydroxide, C TMA-Cl represents the concentration of tetramethylammonium chloride, k represents the reaction rate constant, r(C TMAH ) represents the loss rate function, i.e., the rate at which the generated tetramethylammonium hydroxide decreases due to side reactions or degradation;

[0082] During the reaction, the change of temperature has a significant effect on the generation rate constant k;

[0083] The degradation or by-product generation rate of tetramethylammonium hydroxide (TMAH) can be related to its own concentration, which is generally a first-order reaction, that is, the loss rate r(C TMAH ) and C TMAH The specific formula is r(C TMAH )=k d ×C TMAH , where k d represents the degradation rate constant of tetramethylammonium hydroxide;

[0084] Step S202: Sodium hydroxide is set as a substance controlled by mass transfer, and a mass transfer rate model is established. The specific formula is:

[0085] ,

[0086] Among them, N NaOHrepresents the mass transfer rate model, that is, the mass transfer rate of sodium hydroxide, k L represents the liquid film mass transfer coefficient, a represents the phase interface area, C NaOH,bulk represents the concentration of sodium hydroxide in the bulk phase, C NaOH,inter represents the concentration of sodium hydroxide in the interfacial phase;

[0087] Under steady-state conditions, the generation rate of tetramethylammonium hydroxide and the mass transfer rate of sodium hydroxide satisfy the equilibrium relationship;

[0088] Step S203: During the production of tetramethylammonium hydroxide, temperature changes will occur, and a heat balance model is established. The specific formula is:

[0089] ,

[0090] in, represents the thermal equilibrium model, that is, the change of temperature, T represents the reaction temperature, Q react represents the heat released by the reaction, Q cool Indicates the heat removed by the cooling system, C p represents the specific heat capacity of the reaction solution, and m represents the mass of the reaction solution.

[0091] The reaction is the production of tetramethylammonium hydroxide, and the heat released by the reaction is Q react The specific formula is , represents the reaction enthalpy change, V represents the volume of the reactor in the production equipment, , U represents the heat transfer coefficient, A cool represents the cooling area, T cool Indicates the temperature of the cooling medium.

[0092] By comprehensively calculating the reaction rate, mass transfer rate model and heat transfer equilibrium model, a complete mathematical model describing the tetramethylammonium hydroxide (TMAH) production process can be obtained, which is convenient for further application in online control and real-time optimization.

[0093] Step S3: optimizing and updating the model parameters of the tetramethylammonium hydroxide production process model in real time, and controlling the production equipment of tetramethylammonium hydroxide;

[0094] The specific steps of step S3 are:

[0095] Step S301: Set the state variable of the tetramethylammonium hydroxide production equipment at time t to X(t), and the input variable to U(t). , CT MAH (t) represents the concentration of tetramethylammonium hydroxide at time t, C NaOH (t) represents the concentration of sodium hydroxide at time t, C TMA-Cl(t) represents the concentration of tetramethylammonium chloride at time t, T(t) represents the reaction temperature at time t, zz represents the transpose of a vector or matrix, , F NaOH (t) represents the flow rate of sodium hydroxide at time t, P heater (t) represents the power of the heater of the production equipment of tetramethylammonium hydroxide;

[0096] Step S302: Establish a nonlinear state space model of tetramethylammonium hydroxide production equipment, the specific formula is: , Represents the nonlinear state-space model of a tetramethylammonium hydroxide production plant, represents the time-varying parameter;

[0097] In this embodiment, ;

[0098] Step S303: Future The state of the time step is predicted for the future time t+ , the state prediction model formula of tetramethylammonium hydroxide production equipment is:

[0099] ,

[0100] in, represents the state prediction model of tetramethylammonium hydroxide production equipment, that is, the future time t+ The status of the tetramethylammonium hydroxide production facility;

[0101] Step S304: Setting the objective function to solve the state prediction model of the tetramethylammonium hydroxide production equipment to obtain the predicted state X of the tetramethylammonium hydroxide production equipment yc , the specific formula of the objective function is:

[0102] ,

[0103] Among them, J represents the objective function, min represents the minimization function, Qs represents the state error weighting matrix, R represents the control input weighting matrix, X target It represents the desired target state, which usually has requirements such as product quality and output, and N represents the number of prediction steps.

[0104] The state error weighting matrix Qs and the control input weighting matrix R are usually a symmetric positive definite matrix. The objective function consists of two parts: the state error penalty: , which is used to minimize the error between the predicted state and the target state and control the input cost: , used to constrain the change of control input and prevent over-adjustment;

[0105] Control implementation: 1) Real-time monitoring: Use sensors to measure system status (such as temperature, concentration, etc.) in real time and input the data into the control system; 2) Prediction and optimization: Based on the current status, predict the future status and minimize the objective function by optimizing the control input; 3) Control execution: Adjust the control input (such as NaOH flow, heating power, etc.) according to the optimization results and feed it back to the production process.

[0106] Step S4: using an adaptive adjustment mechanism to automatically correct control parameters according to fluctuations in environmental and reaction conditions;

[0107] The specific steps of step S4 are:

[0108] Step S401: setting the objective function of the adaptive adjustment mechanism of tetramethylammonium hydroxide production equipment, the specific formula is:

[0109] ,

[0110] in, represents the objective function of the adaptive adjustment mechanism of the tetramethylammonium hydroxide production equipment. By sliding this function downward, the best parameter estimation can be obtained. sj (t) represents the actual output value of the tetramethylammonium hydroxide production equipment, which can be a physical quantity (such as temperature, concentration, etc.), represents the observation vector at time t, The parameter vector representing the tetramethylammonium hydroxide production equipment. The parameters that need to be estimated are usually the control or process-related coefficients in the model (such as reaction rate, heat transfer coefficient, etc.). It represents the weight value at time t, reflecting the influence of the data point in the estimation. A larger weight value indicates that the data at that time is more reliable and has a greater influence. Ts represents the total number of moments.

[0111] Objective function of the adaptive adjustment mechanism of tetramethylammonium hydroxide production equipment It measures the weighted sum of squared errors of all observation points. By minimizing this objective function, the system parameters It is gradually adjusted to minimize the weighted error between the predicted value and the actual output;

[0112] Step S402: Minimize the objective function of the adaptive adjustment mechanism of the tetramethylammonium hydroxide production equipment to obtain the optimal parameter estimation of the tetramethylammonium hydroxide production equipment. The specific formula is:

[0113] ,

[0114] in, represents the optimal parameter estimation of tetramethylammonium hydroxide production equipment;

[0115] Step S403: Estimating the optimal parameters of the tetramethylammonium hydroxide production equipment according to the obtained , real-time control of tetramethylammonium hydroxide production equipment.

[0116] In this embodiment, the purpose of step S3 is to predict the state of the tetramethylammonium hydroxide production equipment and adjust the parameters of the tetramethylammonium hydroxide production equipment in real time according to the predicted state.

[0117] Step S5: Setting an alarm system to trigger an alarm when a parameter exceeds a set threshold, and automatically adjusting the corresponding control parameters through an adaptive adjustment mechanism.

[0118] Example 2 See also Figure 3 , another embodiment provided by the present invention: an online control system for tetramethylammonium hydroxide production equipment, comprising: a data acquisition module, a modeling monitoring module, an optimization control module, an adaptive adjustment module and an early warning module;

[0119] The data acquisition module is used to collect key parameters in the tetramethylammonium hydroxide production equipment in real time and pre-process the collected key parameters in the tetramethylammonium hydroxide production equipment;

[0120] The modeling and monitoring module is used to establish a tetramethylammonium hydroxide production process model and to monitor key parameters in the tetramethylammonium hydroxide production process in real time;

[0121] The optimization control module is used to optimize and update the model parameters of the tetramethylammonium hydroxide production process model in real time and control the production equipment of tetramethylammonium hydroxide;

[0122] The adaptive adjustment module is used to automatically correct the control parameters according to the fluctuations of the environment and reaction conditions by using the adaptive adjustment mechanism;

[0123] The early warning module is used to set up an alarm system, trigger an alarm when a parameter exceeds a set threshold, and automatically adjust the corresponding control parameters through an adaptive adjustment mechanism.

[0124] The optimization control module includes: a space model building unit, a state prediction model building unit and a prediction state solving unit;

[0125] The space model building unit is used to build a nonlinear state space model of a tetramethylammonium hydroxide production device;

[0126] The state prediction model establishing unit is used to establish a state prediction model of tetramethylammonium hydroxide production equipment;

[0127] The predicted state solving unit is used to solve the state prediction model of the tetramethylammonium hydroxide production equipment to obtain the predicted state of the tetramethylammonium hydroxide production equipment.

[0128] The adaptive adjustment module includes: an adaptive function setting unit and an optimal parameter estimation unit;

[0129] The adaptive function setting unit is used to set the objective function of the adaptive adjustment mechanism of the tetramethylammonium hydroxide production equipment;

[0130] The optimal parameter estimation unit is used to minimize the objective function of the self-adaptive adjustment mechanism of the tetramethylammonium hydroxide production equipment to obtain the optimal parameter estimation of the tetramethylammonium hydroxide production equipment.

[0131] In addition, the parts of the above-mentioned technical solutions provided in the embodiments of the present application that are consistent with the implementation principles of the corresponding technical solutions in the prior art are not described in detail to avoid excessive redundancy.

[0132] The specific implementation modes as described above further describe the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation mode of the present invention and is not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0133] The above preset parameters or preset thresholds are all set by technicians in this field according to actual conditions or obtained through large-scale data simulation.

[0134] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. An online control method for tetramethylammonium hydroxide production equipment, characterized in that, The specific steps include: Real-time collection of key parameters in the tetramethylammonium hydroxide production equipment, including: the generation rate of tetramethylammonium hydroxide, the mass transfer rate of sodium hydroxide, and the concentrations of sodium hydroxide and tetramethylammonium chloride, and pre-processing of the collected key parameters in the tetramethylammonium hydroxide production equipment; Establish a tetramethylammonium hydroxide production process model and conduct real-time monitoring of key parameters in the tetramethylammonium hydroxide production process; Real-time optimization and update of model parameters of tetramethylammonium hydroxide production process model, and control of tetramethylammonium hydroxide production equipment; Utilizes an adaptive adjustment mechanism to automatically correct control parameters based on fluctuations in environmental and reaction conditions; Set up an alarm system to trigger an alarm when the parameters exceed the set threshold, and automatically adjust the corresponding control parameters through an adaptive adjustment mechanism.

2. An online control method for tetramethylammonium hydroxide production equipment as claimed in claim 1, characterized in that: The tetramethylammonium hydroxide production process model is established to monitor the key parameters in the tetramethylammonium hydroxide production process in real time, including: Sodium hydroxide and tetramethylammonium chloride are used as reactants to generate tetramethylammonium hydroxide. The generation rate of tetramethylammonium hydroxide is assumed to be proportional to the concentration of sodium hydroxide and tetramethylammonium chloride. The generation rate of tetramethylammonium hydroxide is calculated as follows: ， in, represents the generation rate of tetramethylammonium hydroxide, C TMAH represents the concentration of tetramethylammonium hydroxide, t represents the time, C NaOH Indicates the concentration of sodium hydroxide, C TMA-Cl represents the concentration of tetramethylammonium chloride, k represents the reaction rate constant, r(C TMAH ) represents the loss rate function; Assuming sodium hydroxide as a substance controlled by mass transfer, a mass transfer rate model is established. The specific formula is: ， Among them, N NaOH represents the mass transfer rate model, that is, the mass transfer rate of sodium hydroxide, k L represents the liquid film mass transfer coefficient, a represents the phase interface area, C NaOH,bulk represents the concentration of sodium hydroxide in the bulk phase, C NaOH,inter represents the concentration of sodium hydroxide in the interfacial phase; In the production process of tetramethylammonium hydroxide, temperature changes will occur. A thermal balance model is established. The specific formula is: ， in, represents the thermal equilibrium model, that is, the change of temperature, T represents the reaction temperature, Q react represents the heat released by the reaction, Q cool Indicates the heat removed by the cooling system, C p represents the specific heat capacity of the reaction solution, and m represents the mass of the reaction solution.

3. An online control method for tetramethylammonium hydroxide production equipment as claimed in claim 1, characterized in that: The method of optimizing and updating the model parameters of the tetramethylammonium hydroxide production process model in real time and controlling the production equipment of tetramethylammonium hydroxide comprises: Assume that the state variable of the tetramethylammonium hydroxide production equipment at time t is X(t), and the input variable is U(t). , CT MAH (t) represents the concentration of tetramethylammonium hydroxide at time t, C NaOH (t) represents the concentration of sodium hydroxide at time t, C TMA-Cl (t) represents the concentration of tetramethylammonium chloride at time t, T(t) represents the reaction temperature at time t, zz represents the transpose of a vector or matrix, , F NaOH (t) represents the flow rate of sodium hydroxide at time t, P heater (t) represents the power of the heater of the production equipment of tetramethylammonium hydroxide; A nonlinear state space model of tetramethylammonium hydroxide production equipment is established. The specific formula is: , Represents the nonlinear state-space model of a tetramethylammonium hydroxide production plant, represents the time-varying parameter; Step S303: Future The state of the time step is predicted for the future time t+ , the state prediction model formula of tetramethylammonium hydroxide production equipment is: ， in, represents the state prediction model of tetramethylammonium hydroxide production equipment, that is, the future time t+ Status of the tetramethylammonium hydroxide production facility.

4. An online control method for tetramethylammonium hydroxide production equipment as claimed in claim 3, characterized in that: The real-time optimization and updating of the model parameters of the tetramethylammonium hydroxide production process model to control the production equipment of tetramethylammonium hydroxide also includes: Set the objective function to solve the state prediction model of tetramethylammonium hydroxide production equipment and obtain the predicted state X of tetramethylammonium hydroxide production equipment. yc , the specific formula of the objective function is: ， Among them, J represents the objective function, min represents the minimization function, Qs represents the state error weighting matrix, R represents the control input weighting matrix, X target represents the desired target state, and N represents the number of predicted steps.

5. An online control method for tetramethylammonium hydroxide production equipment according to claim 1, characterized in that: The adaptive adjustment mechanism is used to automatically correct the control parameters according to the fluctuations of the environment and reaction conditions, including: The objective function of the adaptive adjustment mechanism of tetramethylammonium hydroxide production equipment is set as follows: ， in, represents the objective function of the adaptive adjustment mechanism of tetramethylammonium hydroxide production equipment, X sj (t) represents the actual output value of the tetramethylammonium hydroxide production equipment, represents the observation vector at time t, represents the parameter vector of the tetramethylammonium hydroxide production facility, represents the weight value at time t, and Ts represents the total number of moments; Minimize the objective function of the adaptive adjustment mechanism of the tetramethylammonium hydroxide production equipment and obtain the optimal parameter estimation of the tetramethylammonium hydroxide production equipment. The specific formula is: ， in, represents the optimal parameter estimation of tetramethylammonium hydroxide production equipment; According to the obtained optimal parameters of tetramethylammonium hydroxide production equipment, it is estimated , real-time control of tetramethylammonium hydroxide production equipment.

6. An online control method for tetramethylammonium hydroxide production equipment according to claim 1, characterized in that: The key parameters in the tetramethylammonium hydroxide production equipment also include: temperature, pH, concentration and liquid level parameters.

7. An online control method for tetramethylammonium hydroxide production equipment according to claim 1, characterized in that: The preprocessing includes: sensor calibration, data cleaning and data smoothing; The sensor calibration uses a set correction factor to correct the reading of each sensor; The data cleaning removes redundant and duplicate data; The data smoothing process uses a sliding average method to smooth the real-time data.

8. An online control system for tetramethylammonium hydroxide production equipment, used to implement an online control method for tetramethylammonium hydroxide production equipment according to any one of claims 1 to 7, characterized in that: include: Data acquisition module, modeling monitoring module, optimization control module, adaptive adjustment module and early warning module; The data acquisition module is used to collect key parameters in the tetramethylammonium hydroxide production equipment in real time, including: the generation rate of tetramethylammonium hydroxide, the mass transfer rate of sodium hydroxide and the concentrations of sodium hydroxide and tetramethylammonium chloride, and pre-process the collected key numbers in the tetramethylammonium hydroxide production equipment; The modeling and monitoring module is used to establish a tetramethylammonium hydroxide production process model and to monitor key parameters in the tetramethylammonium hydroxide production process in real time; The optimization control module is used to optimize and update the model parameters of the tetramethylammonium hydroxide production process model in real time and control the production equipment of tetramethylammonium hydroxide; The adaptive adjustment module is used to automatically correct the control parameters according to the fluctuations of the environment and reaction conditions by using the adaptive adjustment mechanism; The early warning module is used to set up an alarm system, trigger an alarm when a parameter exceeds a set threshold, and automatically adjust the corresponding control parameters through an adaptive adjustment mechanism.

9. An online control system for tetramethylammonium hydroxide production equipment as claimed in claim 8, characterized in that: The optimization control module includes: a space model building unit, a state prediction model building unit and a prediction state solving unit; The space model building unit is used to build a nonlinear state space model of a tetramethylammonium hydroxide production device; The state prediction model establishing unit is used to establish a state prediction model of tetramethylammonium hydroxide production equipment; The predicted state solving unit is used to solve the state prediction model of the tetramethylammonium hydroxide production equipment to obtain the predicted state of the tetramethylammonium hydroxide production equipment.

10. An online control system for tetramethylammonium hydroxide production equipment according to claim 9, characterized in that: The adaptive adjustment module includes: an adaptive function setting unit and an optimal parameter estimation unit; The adaptive function setting unit is used to set the objective function of the adaptive adjustment mechanism of the tetramethylammonium hydroxide production equipment; The optimal parameter estimation unit is used to minimize the objective function of the self-adaptive adjustment mechanism of the tetramethylammonium hydroxide production equipment to obtain the optimal parameter estimation of the tetramethylammonium hydroxide production equipment.

Images