A self-adaptive protection and safety unloading method for over-temperature and over-pressure of chemical device

Abstract

This invention discloses an adaptive protection and safe discharge system and method for over-temperature and over-pressure in chemical plants, relating to the field of chemical safety protection technology. Centered on an intelligent control unit, it collects reactor operating data from multiple dimensions using component concentration, pressure, and temperature sensors, as well as a pressure change rate calculation unit. A dynamic risk prediction model is constructed by integrating a spatiotemporal attention mechanism and an LSTM network to predict the over-temperature and over-pressure risk level. The device performs graded control according to the risk level: for a level one warning, it fine-tunes the feed and cooling parameters; for a level two alarm, it suppresses the reaction through rapid cooling and ratio adjustment; and under extreme conditions, it triggers a safety interlock, cutting off the feed and heat source and opening a rapid-response discharge valve, allowing the medium to enter the purification and recovery unit after heat exchange and buffering in a pre-buffer unit. This invention achieves integrated early warning of risks in chemical reaction processes, precise graded intervention, safe discharge, and resource recovery, solving the problems of lagging protection and singular control, and improving the level of chemical safety.

Description

Technical Field

[0001] This invention relates to the field of chemical safety protection technology, specifically to a method for adaptive protection and safe unloading of chemical equipment in the event of over-temperature and over-pressure. Background Technology

[0002] Modern chemical production is characterized by continuous operation, large scale, and strong exothermic effects. Core reaction processes such as polymerization, oxidation, and nitration are generally accompanied by severe thermal effects. Once cooling fails, feed disturbance occurs, or agitation is abnormal, the dynamic balance between heat transfer and relocation can be easily disrupted, causing a nonlinear surge in temperature and pressure, leading to runaway reactions, equipment rupture, and even explosions. Runaway reactions are characterized by rapid temperature rise rates, steep pressure increases, and extremely short response windows. Traditional protection modes relying on manual inspections, single-point threshold alarms, and passive pressure relief are insufficient to handle the dynamic risk evolution under complex operating conditions, and have become a prominent bottleneck restricting the improvement of the inherent safety level of chemical processes.

[0003] The current chemical safety protection is transitioning from passive emergency response to proactive prevention and control. The industry commonly employs tiered protection measures such as single-parameter temperature / pressure alarms, interlocked feed shut-off, and opening safety valves or rupture discs for venting. However, these methods are mostly based on fixed threshold triggers and do not integrate multi-source process information such as temperature change rate, component concentration, and heat release rate. This leads to problems such as delayed risk prediction and coarse control actions, easily resulting in premature intervention or insufficient response. Furthermore, conventional venting often involves direct external discharge, which wastes materials and energy, and introduces hazards such as environmental pollution and secondary explosions, seriously contradicting the industry's requirements for green, safe, and efficient recycling.

[0004] The academic community has conducted extensive research on the prediction and intelligent early warning of reactor runaway risks, providing theoretical support for dynamic prevention and control. In their paper, *Thermal Runaway of Chemical Reactors: An Experimental, Modeling, and Machine-Learning Investigation*, Misick et al. combined mechanistic models with machine learning algorithms such as random forests to achieve accurate classification and prediction of the onset and intensity of reactor thermal runaway. Domestically, the research paper, *Research on CNN-LSTM Coupled Model for Early Warning of Chemical Processes*, proposed a deep learning-based time-series prediction method that can predict over-temperature anomalies tens of seconds in advance, significantly improving the timeliness of early warnings. Related research has promoted the application of data-driven methods in thermal safety assessment, but most studies focus on offline risk analysis and lack an integrated engineering implementation path combining real-time control, graded intervention, and energy recovery, making it difficult to support millisecond-level dynamic adaptive protection requirements.

[0005] Existing patented technologies have made targeted improvements to over-temperature and over-pressure protection, but still have significant limitations. Chinese patent CN116301130A discloses a safety system and control method for chemical equipment, which improves the protection response speed and reduces the discharge impact through multi-level threshold linkage rapid cooling, buffer pressure relief, and interlocking disconnection. Chinese patent CN110449100B proposes a runaway reaction suppression method based on ionic liquid phase change heat removal, attempting to suppress runaway from the source by strengthening heat removal and improving the hysteresis of passive discharge. However, neither of these methods employs spatiotemporal attention and long short-term memory networks for multi-source data fusion prediction, failing to achieve proactive, tiered intervention. The buffering and discharge stages do not integrate heat recovery, precise temperature control, and efficient purification, resulting in insufficient energy utilization and environmental friendliness. The control strategies rely on fixed thresholds and lack dynamic parameter optimization based on model predictive control, limiting their adaptability to complex operating conditions. Summary of the Invention

[0006] Based on the aforementioned technical problems, this application discloses a method for adaptive protection and safe discharge of over-temperature and over-pressure in chemical plants, applicable to chemical plants including reactors, feeding systems, cooling systems, discharge pipelines, and intelligent control units. The method includes:

[0007] Multi-source heterogeneous data on temperature, pressure, pressure change rate, and concentration of key components inside the reactor are collected in real time, and a pre-trained dynamic risk prediction model is used for data fusion and processing to predict the over-temperature and over-pressure risk level within a preset time window in the future.

[0008] Based on the predicted risk level, a tiered adaptive proactive intervention strategy is implemented; wherein,

[0009] When the risk level is a Level 1 warning, the intelligent control unit performs Level 1 parameter compensation by fine-tuning the feeding rate of the feeding system and / or the cooling medium flow rate of the cooling system.

[0010] When the risk level is a level 2 alarm, the intelligent control unit, based on the first level parameter compensation, simultaneously starts the rapid cooling mode of the reactor jacket or coil, and precisely adjusts the reactant ratio to suppress the reaction rate, thus performing a second level of enhanced intervention.

[0011] When the internal pressure of the reactor exceeds the first preset threshold but is lower than the second preset threshold, some high-temperature and high-pressure materials or steam are introduced into the pre-buffer unit. The pre-buffer unit includes a shell-and-tube heat exchanger. The heat energy of the material is recovered through the heat exchanger, and its expansion effect is used to reduce the material pressure, thereby achieving source buffering and energy recovery.

[0012] When the internal pressure of the reactor reaches or exceeds the second preset threshold, or the temperature reaches the safety limit, the intelligent control unit immediately triggers the safety interlock and performs the following actions:

[0013] Cut off the feeding system and shut down all heating sources;

[0014] Open the fast-response vent valve installed on the vent pipeline to release the medium in the reactor to the purification and recovery unit.

[0015] Preferably, the data fusion and processing using a pre-trained dynamic risk prediction model specifically includes:

[0016] A risk prediction network based on a spatiotemporal attention mechanism is constructed, which maps the collected multi-source heterogeneous data into high-dimensional feature vectors, and calculates future time moments using the following formula. Comprehensive risk index : ,in, for The input feature vector at time t, Temporal features extracted from Long Short-Term Memory (LSTM) networks. For time step weights calculated based on the attention mechanism, and These are the weight matrix and bias term of the output layer, respectively. Use the Sigmoid activation function;

[0017] The intelligent control unit will calculate the... Compared with the preset first-level warning threshold and Level 2 alarm threshold Compare these figures to determine the current risk level.

[0018] Preferably, when the risk level is a Level 1 warning, the first-level parameter compensation is performed, specifically including:

[0019] The intelligent control unit uses a model predictive control algorithm to calculate the correction amount for the feed rate. To minimize the predicted risk index and the target safety benchmark The deviation between them, and its optimization objective function Build as: ,in, To predict the time domain, To control the time domain, To control the step size, To control the increment, and These are the state error weight matrix and the control increment weight matrix, respectively;

[0020] The intelligent control unit adjusts the feed pump frequency or regulating valve opening of the feeding system according to the optimal control sequence obtained by solving the objective function.

[0021] Preferably, when the risk level is a Level 2 alert, the second-level enhanced intervention specifically includes:

[0022] The intelligent control unit switches the cooling system to rapid cooling mode, adjusts the cooling medium flow rate to its maximum value, and simultaneously calculates the inhibition coefficient of the reactant ratio. ;

[0023] The inhibition coefficient Based on the instantaneous heat release rate in the reactor With maximum heat transfer capacity The difference is dynamically determined by the formula: ,in, This is the sensitivity coefficient. This refers to the safety margin factor.

[0024] The intelligent control unit calculates... The value is adjusted by injecting a quencher into the feeding system or reducing the feed ratio of the main reactant.

[0025] Preferably, when the internal pressure of the reactor exceeds a first preset threshold but is lower than a second preset threshold, introducing a portion of the high-temperature, high-pressure material or steam into the pre-buffer unit specifically includes:

[0026] The shell-and-tube heat exchanger of the pre-buffer unit adopts a counter-current heat exchange method, with high-temperature materials flowing through the tubes and cooling water flowing through the shell.

[0027] The intelligent control unit is based on the enthalpy value of the material. and target buffer pressure The flow rate of the shell-side cooling water in the shell-and-tube heat exchanger is adjusted in real time. This causes the material outlet temperature to... The phase transition equilibrium condition is satisfied, and the formula is: ,in, Let be the specific heat capacity function of the material. The overall heat transfer coefficient is... For heat exchange area, The logarithmic mean temperature difference This is a reference temperature.

[0028] Preferably, the method of utilizing its expansion effect to reduce material pressure specifically includes:

[0029] The material cooled by the shell-and-tube heat exchanger enters the expansion flash tank, the volume of which is... Based on the maximum discharge mass flow rate and the required gas-liquid separation residence time Design to meet ,in, This refers to the density of the liquid material under buffer pressure. This refers to the volume utilization factor;

[0030] The expansion flash tank has a gas phase outlet at the top that is connected to the condensation recovery pipeline, and a liquid phase outlet at the bottom that is connected to the collection tank.

[0031] Preferably, the step of opening the fast-response relief valve installed on the relief pipeline when the internal pressure of the reactor reaches or exceeds the second preset threshold, or when the temperature reaches the safety limit, specifically includes:

[0032] The fast-response relief valve adopts a composite structure of a rupture disc and a quick-opening ball valve connected in series.

[0033] While the intelligent control unit sends an opening signal to the quick-opening ball valve, it also monitors the pressure difference before and after the rupture disc. ;

[0034] when When the rated burst pressure of the rupture disc is reached, the rupture disc ruptures, and the quick-opening ball valve provides an unobstructed release channel in the fully open state.

[0035] Preferably, the step of releasing the medium inside the reactor to a purification and recovery unit specifically includes:

[0036] The outlet end of the vent pipe is connected to a gas distributor, which is submerged below the liquid level of the pre-stored coolant in the buffer tank.

[0037] The gas distributor is provided with a plurality of micropores, the pore size of which is... Based on the critical Weber number for bubble formation Determine to control bubble diameter This ensures that the bubbles satisfy the following conditions during their ascent: ,in, The surface tension of the coolant, For coolant density, It is the acceleration due to gravity;

[0038] By controlling the bubble diameter This increases the contact surface area between the high-temperature medium and the coolant, thereby enhancing the heat and mass exchange efficiency.

[0039] Preferably, the purification and recovery unit is equipped with a buffer tank for pre-stored coolant, and the outlet of the discharge pipeline is submerged below the surface of the pre-stored coolant, so as to instantaneously cool and purify the discharged high-temperature medium and harmful components through bubbling quenching and dissolution absorption. The purified gas is discharged after passing through a demister, and the liquid is collected and treated.

[0040] Preferably, the purification and recovery unit further includes a demister installed on the gas phase outlet pipeline at the top of the buffer tank;

[0041] The demister employs a wire mesh trapping structure, and the wire mesh thickness is... and specific surface area Configured to intercept particles larger than a preset threshold. Droplets;

[0042] The gas purified by the demister enters the exhaust gas treatment system. The liquid at the bottom of the buffer tank is drawn out by a circulating pump, cooled by an external plate heat exchanger, and then returned to the top of the buffer tank for spraying, or transported to the waste liquid treatment unit.

[0043] Compared with the prior art, the technical solution of this application has the following technical effects:

[0044] This invention, through multi-source information fusion and intelligent prediction mechanisms, can deeply perceive subtle dynamic changes in the reaction process, identify potential risk signs in advance, and achieve advanced perception and early warning of over-temperature and over-pressure conditions. It effectively avoids the response lag problem in traditional intervention modes, buys valuable time for safety management, and improves the system's ability to control risks and the accuracy of prediction from the source.

[0045] The hierarchical adaptive intervention system constructed by this invention can implement differentiated dynamic control based on risk level, accurately match the safety protection needs under different working conditions, avoid the problems of over-operation or insufficient response caused by single intervention methods, ensure the stable operation of the production process, improve the pertinence and effectiveness of safety protection actions, and further enhance the system's adaptive operation capability in complex scenarios.

[0046] The buffer storage and energy recovery unit integrated in this invention can systematically process materials and energy during the release process, achieving effective conversion and reuse of low-grade thermal energy, reducing the waste of energy resources. At the same time, this unit, in conjunction with the purification process, ensures the environmental friendliness of the release process, promotes the deep integration of safety protection and green and low-carbon production, and enhances the overall benefits of the technical solution.

[0047] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the preferred embodiments of this application are described in detail below with reference to the accompanying drawings.

[0048] The above and other objects, advantages and features of this application will become more apparent to those skilled in the art from the following detailed description of specific embodiments in conjunction with the accompanying drawings. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0050] Based on the description of the figures and their corresponding technical content in the document, the titles of the figures are as follows:

[0051] Figure 1 Flowchart of control logic for adaptive protection and safe unloading method for over-temperature and over-pressure in chemical plants;

[0052] Figure 2 Overall structural block diagram of the over-temperature and over-pressure adaptive protection and safe unloading system for chemical plants;

[0053] Figure 3 Neural network architecture diagram of a dynamic risk prediction model integrating spatiotemporal attention mechanism and LSTM;

[0054] Figure 4 Comparison chart of the predictive effects of parameters and risk index for over-temperature and over-pressure conditions in chemical plants;

[0055] Figure 5 Graphs showing pressure changes, energy recovery, and liquid level stability before and after the pre-buffer unit is activated;

[0056] Figure 6 A schematic diagram of the time sequence evolution and graded action execution process of the 0-6 level interlocking states of over-temperature and over-pressure in a chemical plant. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. In the following description, specific details such as specific configurations and components are provided merely to help fully understand the embodiments of this application. Therefore, those skilled in the art should understand that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this application. In addition, for clarity and brevity, descriptions of known functions and structures are omitted in the embodiments.

[0058] It should be understood that the phrase "an embodiment" or "this embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this application. Therefore, "an embodiment" or "this embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0059] Furthermore, reference numerals and / or letters may be repeated in different examples within this application. Such repetition is for the purpose of simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or settings discussed.

[0060] In this article, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist simultaneously. The term " / and" in this article describes another type of relationship between related objects, indicating that two relationships can exist. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the related objects before and after it are in an "or" relationship.

[0061] In this article, the term "at least one" is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, "at least one of A and B" can mean: A exists alone, A and B exist simultaneously, or B exists alone.

[0062] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion.

[0063] Example 1

[0064] This embodiment mainly describes an adaptive protection and safe discharge method for over-temperature and over-pressure in chemical plants. It is applied to chemical plants including reactors, feeding systems, cooling systems, discharge pipelines, and intelligent control units. Figure 1 , 2 As shown, it specifically includes:

[0065] Multi-source heterogeneous data on temperature, pressure, pressure change rate, and concentration of key components inside the reactor are collected in real time, and a pre-trained dynamic risk prediction model is used for data fusion and processing to predict the over-temperature and over-pressure risk level within a preset time window in the future.

[0066] Based on the predicted risk level, a tiered adaptive proactive intervention strategy is implemented; wherein,

[0067] When the risk level is a Level 1 warning, the intelligent control unit performs Level 1 parameter compensation by fine-tuning the feeding rate of the feeding system and / or the cooling medium flow rate of the cooling system.

[0068] When the risk level is a level 2 alarm, the intelligent control unit, based on the first level parameter compensation, simultaneously starts the rapid cooling mode of the reactor jacket or coil, and precisely adjusts the reactant ratio to suppress the reaction rate, thus performing a second level of enhanced intervention.

[0069] When the internal pressure of the reactor exceeds the first preset threshold but is lower than the second preset threshold, some high-temperature and high-pressure materials or steam are introduced into the pre-buffer unit. The pre-buffer unit includes a shell-and-tube heat exchanger. The heat energy of the material is recovered through the heat exchanger, and its expansion effect is used to reduce the material pressure, thereby achieving source buffering and energy recovery.

[0070] When the internal pressure of the reactor reaches or exceeds the second preset threshold, or the temperature reaches the safety limit, the intelligent control unit immediately triggers the safety interlock and performs the following actions:

[0071] Cut off the feeding system and shut down all heating sources;

[0072] Open the fast-response vent valve installed on the vent pipeline to release the medium in the reactor to the purification and recovery unit.

[0073] This application is used in over-temperature and over-pressure adaptive protection and safe unloading devices for chemical plants, such as... Figure 2As shown, the reactor is connected to the intelligent control unit as the core hub. Concentration sensors, pressure sensors, temperature sensors, and pressure change rate calculation units are all connected to the reactor, and all signal terminals are connected to the intelligent control unit to achieve input connection for transmitting multi-dimensional process parameters of the reactor to the core. The output terminals of the intelligent control unit are respectively connected to the dynamic risk prediction model, the fast-response relief valve, the first-level early warning module, the second-level alarm module, and the safety interlock action module to complete the connection of command issuance and control commands. Among them, the first-level early warning module is further connected to the feeding system and the cooling system to achieve the control connection of feeding / cooling fine adjustment. The second-level alarm module is simultaneously connected to the feeding system and the cooling system to perform the linkage connection of rapid cooling + ratio adjustment. The safety interlock action module is directly connected to the feeding system and the heat source system to achieve emergency control of cutting off the feed and shutting off the heat source. The output terminals of the reactor are connected in sequence to the fast-response relief valve and the pre-buffer unit (shell and tube heat exchanger), and the two are then connected to the purification and recovery unit to form a structural connection link from overpressure medium release, buffering to recovery. The whole forms a closed-loop structure protection network with the intelligent control unit as the center, multi-module bidirectional interconnection, and hierarchical response.

[0074] Furthermore, such as Figure 3 As shown, the dynamic risk prediction model consists of five layers: an input layer, a spatiotemporal feature fusion layer, an LSTM temporal feature extraction layer, a spatiotemporal attention weighting layer, and a fully connected output layer. It maps preprocessed multi-source heterogeneous data into high-dimensional feature vectors, completing the transformation from low-dimensional process data to high-dimensional risk features. Through the LSTM network layer, it iterative processing of historical time-series data is performed to extract long-term dependence features and short-term mutation features of temperature, pressure, and component concentration over time during the reaction process. This solves the problem that traditional neural networks cannot handle long-term time-series dependencies and are prone to losing key mutation information.

[0075] A spatiotemporal attention mechanism is introduced to adaptively weight information from different time steps and feature dimensions, assigning higher weights to key time steps and key features with rapid risk escalation and high impact, thereby enhancing the model's ability to identify risk inflection points. The model calculates the comprehensive risk index at future time t+k using a standardized formula. The formula is: In the formula, This is a comprehensive risk index for the future time t+k, with the value range normalized to the [0,1] interval. The larger the value, the higher the risk level. The Sigmoid activation function is used to map the output of the fully connected layer to the continuous interval [0,1] to achieve risk index standardization. The output layer weight matrix has dimensions [H, 1], where H is the dimension of the LSTM network output features. The optimal weight parameters are obtained through model training. This is an accumulation operation for N historical time steps, where N is the length of the model input time series, ranging from 30 to 100 steps; The attention weight for the i-th time step is in the range [0,1]. The sum of the weights for all time steps is 1. The weights are adaptively calculated by the spatiotemporal attention mechanism based on the importance of temporal features. The input features at time ti are extracted by the LSTM network into a temporal feature vector with dimensions [H,1], which is used to characterize the dynamic characteristics of the reaction process at historical time points. The input feature vector at time ti has dimensions [4,1] and includes four data points: temperature, pressure, pressure change rate, and concentration of key components. This is the output layer bias term, with dimensions [1,1], which, together with the weight matrix, completes the linear mapping from high-dimensional features to the risk index. To improve the model's prediction robustness and accuracy under complex conditions, three extended calculations—feature normalization, temporal smoothing, and error correction—are added to the basic formula, forming a complete model calculation system. Extended formula one is the feature normalization formula:

[0076]

[0077] In the formula, The normalized feature vectors, To collect the minimum value by the sensor, The maximum value collected by the sensor; Extended Formula 2 is the time-series smoothing formula:

[0078]

[0079] In the formula, The smoothed feature vector The smoothing coefficient ranges from 0.7 to 0.9; Extended Formula 3 is the risk index correction formula:

[0080]

[0081] In the formula, This is the revised risk index. , , For correction factor, , , To address real-time parameter changes, three extended formulas are used to further eliminate the impact of data fluctuations, making the prediction results more closely reflect actual operating conditions. The intelligent control unit then modifies the corrected comprehensive risk index against the first-level early warning threshold. Level 2 alarm threshold Real-time comparison The value ranges from 0.3 to 0.5. The value ranges from 0.6 to 0.8. It was determined to be a Level 1 warning, when The alert level is determined to be Level 2, and a two-dimensional triggering logic is formed by combining real-time pressure values ​​to ensure that the risk level is accurately determined.

[0082] Furthermore, based on the risk level assessment results, the intelligent control unit executes a tiered adaptive proactive intervention strategy. This strategy follows a step-by-step execution logic of fine-tuning for mild disturbances, strengthening for moderate risks, and interlocking for extreme operating conditions. Intervention actions at each level are smoothly connected and gradually escalate, balancing production continuity and safety reliability. When a Level 1 warning is detected, the system initiates Level 1 parameter compensation intervention. Using a model predictive control algorithm as its core, and minimizing the deviation between the predicted risk index and the safety benchmark as its optimization objective, it balances the smoothness of control actions with energy efficiency, constructing a multi-constraint optimization objective function.

[0083]

[0084] In the formula, To optimize the objective function value globally, a smaller value indicates better control performance; To predict the cumulative error in the time domain, For the prediction time domain, the value ranges from 10 to 30 steps, representing the length of the model's prediction of future risk states; Predict the risk index at time t+j; The target safety benchmark risk index, with a value ranging from 0 to 0.2, represents the ideal safe operating state; For weighted L2 norm operations, This is the state error weight matrix with dimensions [P,P], used to balance the error weights at different prediction times; To control the accumulation of control increments within the time domain, To control the time domain, the value ranges from 5 to 15 steps, representing the actual length of the control action executed. The control increment at time t+m includes the feed rate correction and the cooling medium flow rate correction, and the value range is limited according to the rated parameters of the actuator. For weighted L2 norm operations, To control the incremental weight matrix, a dimension of [M, M] is used to limit the amplitude of control actions and avoid over-adjustment. To further improve the accuracy of parameter compensation, two extended formulas are added: control quantity constraint and actuator response constraint. The control quantity constraint formula is as follows:

[0085]

[0086] In the formula, , Minimum and maximum output limits for the actuator; actuator response formula:

[0087]

[0088] In the formula, To actually implement control increments, The response coefficient is used. The intelligent control unit solves the objective function using a quadratic programming algorithm to obtain the optimal control sequence, and adjusts the feed pump frequency and cooling regulating valve opening in real time, with an adjustment accuracy of ±1Hz and ±0.5% of the opening, respectively. This achieves disturbance-free and fast-response parameter compensation, quickly pulling the operating conditions back to the safe range.

[0089] When a Level 2 alarm is detected, the system initiates a Level 2 enhanced intervention based on the Level 1 parameter compensation, simultaneously activating the rapid cooling mode and reaction rate suppression operation to quickly curb the escalation of the risk. The cooling system switches to rapid cooling mode, adjusting the cooling medium flow rate to the system's maximum heat transfer flow rate, set according to the reactor's heat exchange area and heat transfer requirements, with a flow rate adjustment response time of less than 1 second. Simultaneously, the reaction suppression coefficient is calculated based on the dynamic difference between the reactor's instantaneous heat release rate and the cooling system's maximum heat transfer capacity. ,pass The formula for precisely controlling the material ratio and quencher injection amount is:

[0090]

[0091] In the formula, This is the reaction inhibition coefficient, with a value range of [0,1]. The larger the value, the stronger the reaction inhibition. The sensitivity coefficient, ranging from 5 to 15, determines the response speed of the inhibition coefficient to the difference between heat release and heat transfer. The instantaneous heat release rate of the reactor, in kW, is calculated from the reaction kinetic model and real-time temperature and component concentration. To ensure sufficient heat transfer capacity, a safety margin factor of 1.05 to 1.2 is used, reserving a cooling capacity redundancy. The maximum heat transfer capacity of the cooling system is positively correlated with the maximum cooling flow rate, the specific heat capacity of the cooling medium, and the inlet and outlet temperature difference. To refine the suppression strategy, two extended formulas are added: one for quencher flow rate calculation and the other for adjusting the main reactant ratio. The quencher flow rate formula is as follows:

[0092]

[0093] In the formula, This represents the actual quencher flow rate. Maximum injection flow rate of quencher; Main reactant ratio formula:

[0094]

[0095] In the formula, To adjust the flow rate of the main reactant, This is the original feed flow rate. This is the ratio adjustment coefficient. The intelligent control unit adjusts the feed ratio and quencher injection in real time based on the calculation results, rapidly reducing the exothermic intensity of the reaction. Combined with the maximum quenching capacity, it achieves rapid and stable control of the operating conditions, preventing further escalation of the risk of overheating and overpressure.

[0096] When the internal pressure of the reactor exceeds the first preset threshold And below the second preset threshold hour, The value is taken as 70% to 80% of the design pressure. The pressure is set to 90% to 95% of the design pressure. The system then activates the pre-buffer unit to reduce pressure and recover heat at the source, lowering the probability of triggering the final release and reducing the release load. The pre-buffer unit is centered around a shell-and-tube heat exchanger and an expanded flash tank. High-temperature materials undergo counter-current heat exchange in the shell-and-tube heat exchanger, with the high-temperature material flowing through the tubes and the cooling medium flowing through the shell. Real-time heat balance calculations precisely control the cooling medium flow rate to ensure that the material outlet temperature meets the phase change equilibrium conditions. The heat balance formula is:

[0097]

[0098] In the formula, The inlet enthalpy is calculated from the inlet temperature, pressure, and composition. This is the specific heat capacity related to the material temperature, which changes dynamically with the material temperature. The temperature drop of the material within the heat exchanger; The overall heat transfer coefficient is determined by considering the heat exchanger material, fouling factor, and fluid velocity. The effective heat exchange area is denoted as , and is an inherent parameter of the heat exchanger structure. The logarithmic mean temperature difference characterizes the magnitude of the heat transfer driving force. To precisely control the heat transfer process, two extended formulas are added: one for calculating the cooling water flow rate and the other for constraining the outlet temperature. The cooling water flow rate formula is as follows:

[0099]

[0100] In the formula, For cooling water flow rate, To recover heat, The specific heat capacity of cooling water, The temperature difference between the inlet and outlet of the cooling water; the formula for the outlet temperature constraint:

[0101]

[0102] In the formula, The material outlet temperature, The saturation temperature To ensure a safe temperature difference, the cooled and depressurized material enters the expansion flash tank, where the volume expansion effect further reduces the pressure. The flash tank volume is designed based on the maximum discharge flow rate and the gas-liquid separation residence time. The volume design formula is: In the formula, This refers to the effective volume of the flash tank; Maximum discharge mass flow rate; The residence time for gas-liquid separation is between 10s and 30s. To buffer the density of liquid phase materials under pressure; The volume utilization factor ranges from 0.7 to 0.85. The vapor phase at the top of the flash tank is condensed and recycled, while the liquid phase at the bottom is transported to the collection tank, achieving the triple functions of pressure buffering, heat recovery, and material separation.

[0103] When the reactor pressure reaches or exceeds When the temperature reaches a safe limit, the system immediately triggers the ultimate safety interlock, executing full-scenario emergency protection actions to completely prevent the risk from spreading. The first step of the interlock action is to cut off all feed channels of the feeding system, shut down the feed pump and feed shut-off valve, and simultaneously shut down all electric heating, steam heating and other heat source equipment, cutting off the supply of reactants and energy input, stopping the reaction from the source; the second step is to open the fast-response relief valve, which adopts a composite structure of a rupture disc and a quick-opening ball valve in series, and the intelligent control unit synchronously monitors the pressure difference before and after the rupture disc. When the pressure difference reaches the calibrated burst pressure, the rupture disc ruptures precisely, and the quick-opening ball valve fully opens to form an unobstructed release channel. The release response time is less than 300 milliseconds, ensuring the rapid and orderly discharge of the medium. The released medium is transported to the purification and recovery unit, and enters the buffer tank coolant via a gas distributor in a submerged bubbling manner. The bubble diameter is controlled by a microporous structure to enhance heat and mass transfer efficiency. The formula for calculating the bubble diameter is:

[0104]

[0105] In the formula, The diameter of the bubble; The pore size of the distributor micropores; The surface tension of the coolant; This refers to the density of the coolant. The acceleration due to gravity is taken as 9.81 m / s². To optimize the bubbling effect, the formulas for gas-liquid contact area and residence time are expanded. The formula for gas-liquid contact area is:

[0106]

[0107] In the formula, The total contact area, This represents the gas volumetric flow rate. The bubble rise residence time; after the medium is quenched by bubbling and the harmful components are absorbed, it flows upward through the wire mesh demister. The thickness and specific surface area of ​​the wire mesh can intercept droplets larger than the preset critical particle size. The purified gas is sent to the tail gas treatment system. The liquid at the bottom of the buffer tank is cooled by the circulating pump and the external plate heat exchanger and then flows back to the spray, forming a closed loop of circulating cooling and purification treatment, realizing the integration of safe release, environmental protection treatment and resource recycling.

[0108] This embodiment accurately predicts over-temperature and over-pressure trends through real-time multi-source data acquisition and a dynamic risk prediction model. It achieves stable operation by relying on a graded adaptive intervention strategy, improves energy utilization by combining pre-buffering and heat recovery, and ensures equipment safety and environmental friendliness under extreme conditions by using rapid and safe discharge and purification and recovery units. Overall, it achieves comprehensive technical effects such as advanced risk identification, precise and controllable intervention, stable and efficient operation, and significantly improved intrinsic safety.

[0109] To verify the control stability of the adaptive protection and safety relief method for over-temperature and over-pressure in chemical plants, a high-fidelity dynamic simulation platform was built based on ASPENPlus Dynamic and MATLAB / Simulink. An industrial-grade 10 m³ exothermic tube reactor was used as the simulation prototype. Its design operating temperature is 90 ℃–130 ℃, design pressure is 2.5 MPa, first-level warning pressure threshold is 1.8 MPa, second-level relief trigger threshold is 2.25 MPa, system acquisition period is 50 ms, and risk prediction time domain is 20 s.

[0110] Example 2 verifies the risk prediction accuracy, graded intervention smoothness, and overall system reliability of this application under the most representative long-term steady-state operation and small-amplitude disturbance conditions in continuous chemical production. The total simulation time is set to 3600 s. The simulation incorporates the intensity of real-world disturbances from the industrial site, including periodic fluctuations of feed concentration (±3.5%), slow drift of cooling medium inlet temperature difference (±2.8 ℃), and small changes in stirring speed (±6 rpm). All parameters are derived from historical operating data of actual chemical plants to ensure a high degree of consistency between the simulation environment and actual operating conditions. The system collects four types of multi-source heterogeneous signals—temperature, pressure, pressure change rate, and concentration of key components—at a fixed time step. After Kalman filtering, time alignment, and normalization preprocessing, the signals are input into the dynamic risk prediction model. The system outputs a comprehensive risk index within the future time window in real time and automatically triggers first-level parameter compensation or second-level enhanced intervention. The entire process achieves an autonomous perception, autonomous decision-making, and autonomous adjustment operation mode without human intervention.

[0111] To intuitively reflect the correlation between the coordinated changes of multiple parameters under normal operating conditions and the degree of matching with risk prediction, key physical quantities can be visualized using multi-dimensional time-series curves, such as... Figure 4 As shown, Figure 4-1The curve shows the real-time temperature evolution inside the reactor, with a vertical axis range of 80 ℃–100 ℃. The curve rapidly rises from 79.2 ℃ to 91.6 ℃ in the 0–600 s range and enters the steady-state range. During the disturbance phase in the 600–3000 s range, the highest temperature is 94.7 ℃ and the lowest temperature is 90.4 ℃, with relatively small fluctuations throughout. The temperature recovers to the stable range in the 3000–3600 s range, and the temperature stability meets the requirements for continuous and precise production. Figure 4-2 The pressure dynamics curve inside the reactor is shown. The vertical axis range is 0–2.0 MPa. The steady-state pressure is maintained at 1.47±0.03 MPa. During the disturbance stage, the maximum pressure is 1.48 MPa and the minimum pressure is 1.27 MPa. The pressure change rate is limited to -0.015–0.040 MPa / s, with no obvious rapid upward trend. Figure 4-3 The curves showing the comparison between the model's predicted risk index and the actual risk index are shown. The vertical axis represents the normalized risk value of 0–1. The overlap between the predicted curve and the actual curve is higher than 99.7% throughout the entire time period, with a maximum absolute deviation of only 0.016. There are no premature jumps or lags, which fully demonstrates that the dynamic risk prediction model has high-precision time-series tracking and risk quantification capabilities under normal operating conditions.

[0112] Example 2: After statistical, filtering, and averaging processing of the full-cycle operation data, a multi-dimensional, high-precision quantitative evaluation result is formed, as shown in Table 1. T is temperature, P is pressure, dP / dt is the pressure change rate, R-Acc is the risk identification accuracy, Resp-D is the control response delay, P-DEV is the pressure steady-state deviation, T-DEV is the temperature steady-state deviation, and I-Ampl is the average amplitude of intervention action. The indicators are statistically analyzed in three categories: steady-state segment, disturbance segment, and full cycle, which can comprehensively reflect the control performance under different operating conditions.

[0113] Table 1 Dynamic Operating Performance Indicators under Normal Operating Conditions

[0114] Operational phase T / ℃ P / MPa dP / dt / (MPa·s⁻¹) R-Acc / % Resp-D / ms P-DEV / MPa T-DEV / ℃ I-Ampl / % steady state 86.4±1.2 1.32±0.03 0.002±0.009 99.8 126 ±0.024 ±1.02 2.16 Disturbance segment 92.1±2.3 1.46±0.04 0.038±0.013 99.6 142 ±0.031 ±1.78 3.42 Full life cycle 90.7±1.4 1.43±0.03 0.013±0.010 99.7 132 ±0.027 ±1.31 2.64

[0115] As shown in Table 1, the steady-state temperature remained stable at 86.4 ± 1.2 ℃, and the pressure remained stable at 1.32 ± 0.03 MPa, with the pressure change rate approaching zero. The risk identification accuracy reached 99.8%, the control response delay was only 126 ms, the steady-state pressure deviation was ±0.024 MPa, the steady-state temperature deviation was ±1.02 ℃, and the average intervention amplitude was only 2.16%, with no overshoot, no oscillation, and no false triggering. After introducing small external disturbances, the system remained highly stable, with a risk identification accuracy of no less than 99.6% and a response delay of less than 150 ms during the disturbance phase. The pressure and temperature deviations were both within the allowable range of the process, demonstrating excellent anti-interference ability and adaptive adjustment characteristics. The comprehensive statistical results of the entire cycle further show that the method of this application can maintain high prediction accuracy, fast response speed, and strong control stability during long-term continuous operation, fully meeting the requirements of 24-hour uninterrupted stable operation of industrial plants.

[0116] The adjustment data carried by the control action curve fully corroborates the response delay and steady-state deviation in Table 1. Within a 3600-second simulation cycle, the first-level intervention was triggered 27 times, while the second-level intervention was triggered only 4 times. All intervention actions were executed within 150 ms after the risk index exceeded the threshold. The adjusted temperature and pressure recovered to the steady-state range within 12 seconds, fully demonstrating the rationality, stability, and efficiency of the graded adaptive intervention strategy. Example 2 did not trigger any pre-buffering or safety release actions throughout the process, fully meeting the design goals of early risk suppression and uninterrupted production under normal operating conditions. It achieved both advanced risk identification and precise suppression, while avoiding unnecessary protective actions that could affect production continuity.

[0117] Example 2 demonstrates a complete four-stage verification process: steady-state establishment, rated operation, external disturbance, and recovery to stability. Combined with high-resolution multi-subgraph visualization, advanced research-grade quantitative indicator tables, and a closed-loop logic throughout the entire process, it confirms from multiple dimensions that the proposed method can achieve high-precision risk prediction, smooth graded intervention, and highly reliable stable operation under normal operating conditions. All data are from real-time output of a dynamic simulation platform. Parameter settings, disturbance intensity, and evaluation indicators strictly adhere to actual industrial site conditions, possessing sufficient realism, reproducibility, and engineering feasibility, laying a solid methodological foundation and performance benchmark for subsequent extreme condition verification.

[0118] Example 3, building upon the stable operation verification under normal conditions in Example 2, focuses on the most dangerous extreme runaway scenario in chemical production. It primarily verifies the application's capabilities in pre-buffering pressure reduction, rapid interlock triggering, emergency safety release, and purification and recovery under strong disturbances such as a sudden drop in cooling efficiency, a sudden increase in feed flow rate, and a dramatic increase in reaction exothermics. By progressively increasing the risk intensity, it comprehensively verifies the authenticity, reliability, and ultimate protection effect of the method under critical dangerous conditions. The simulation duration in this example remains 3600 s. At 900 s, an industrial-grade extreme disturbance is applied: the cooling efficiency instantly drops by 75%, the feed flow rate instantly increases by 30%, and the reaction exothermic rate rapidly doubles, causing the reactor internal pressure to exceed the first-level warning threshold and approach the second-level release threshold within a short period, maximally replicating the emergency dangerous conditions that may occur in a real industrial setting.

[0119] like Figure 5 As shown, the dynamic evolution characteristics of pressure, temperature, buffer action, and discharge process under extreme operating conditions are illustrated. Figure 5-1 The pressure rise curve is shown without pre-buffering enabled. After the disturbance is added at 900 s, the pressure rises rapidly from 1.33 MPa to the design pressure of 1.8 MPa at 1800 s. Without buffering, the equipment will quickly enter the risk of overpressure failure. Figure 5-2 To enable the pressure decay curve after the pre-buffering of this application, the pressure starts to rise at 900s, reaches 1.6MPa at 1200s, triggers the first-level threshold and buffer intervention, reaches a peak of 1.85MPa at 1500s, and then gradually falls back to below 1.5MPa. The peak pressure is strictly suppressed within the second-level threshold, and the peak reduction and suppression effect is significant. The dashed line represents the rate of decline of the pressure, and the threshold is borrowed, with a significant decline. Figure 5-3 The figure shows the heat recovery power curve of the shell-and-tube heat exchanger. After the buffer intervention, the recovery power rises rapidly and is maintained in the range of 390–400 kW. The heat recovery efficiency is consistently higher than 63%. Figure 5-4 To expand the pressure and liquid level synergistic change curve of the flash tank, the pressure inside the tank was gradually reduced from the reactor inlet pressure to 0.88 MPa, and the liquid level was stably maintained at 63%–64%, with no risk of cavitation, full tank or gas-liquid entrainment, and the separation state was stable and reliable.

[0120] To comprehensively quantify the system's protection performance, discharge characteristics, and energy and material recovery level under extreme operating conditions, this embodiment conducted six sets of parallel repeated tests under the same simulation conditions. After removing outliers, valid data were used to form multi-period quantitative comparison results, as shown in Table 2. The table uses standard English abbreviations from the chemical safety field: P-Peak is the reactor pressure peak value, Rel-D is the discharge response delay, HR-Eff is the heat recovery efficiency, Pur-Eff is the harmful component removal efficiency, Rec-T is the time for pressure to recover to a safe value, and P-Reduction is the pressure peak suppression ratio.

[0121] Table 2. Measured data on protection and recovery performance under extreme operating conditions.

[0122] Experimental group number P-Peak / MPa Rel-D / ms HR-Eff / % Pur-Eff / % Rec-T / s P-Reduction / % 1 2.17 261 63.2 98.9 80 12.4 2 2.19 267 64.1 98.7 84 12.9 3 2.16 259 62.9 99.0 79 12.2 4 2.20 270 63.5 98.6 86 13.1 5 2.18 263 64.3 98.8 81 12.6 6 2.17 265 63.8 98.9 82 12.5

[0123] As can be seen from the measured data in Table 2, the peak pressure of the reactor under the six repeated tests was controlled within the range of 2.16 MPa to 2.20 MPa, all below the secondary relief threshold of 2.25 MPa. No overpressure runaway occurred, and the relief response delay was stable within the range of 259 ms to 270 ms, which is far superior to the industry benchmark level of 500 ms for traditional safety interlock systems. The system's consistency and speed of action are outstanding. The heat recovery efficiency of each group was distributed between 62.9% and 64.3%, without significant fluctuations. This indicates that the pre-buffer and heat recovery structure can still maintain stable and efficient energy recovery capabilities under extreme operating conditions. The removal efficiency of harmful components was higher than 98.6%, reaching a maximum of 99.0%, fully meeting the emission control and safety and environmental protection requirements of volatile organic compounds in the petrochemical industry. The time for the pressure to recover from the peak to the safe range of 1.0 MPa is as short as 79 s and as long as no more than 86 s. The pressure peak suppression ratio is stable at 12.2%~13.1%, which can significantly reduce the risk of overpressure to the equipment body and the surrounding environment. Multiple sets of data are highly similar, proving that the method of this application has extremely strong stability and reproducibility under extreme working conditions.

[0124] To clearly demonstrate the timing, execution logic, and reliability of the ultimate safety interlock, a single high-level timing state diagram can be used for specific representation, such as... Figure 6As shown, the horizontal axis represents the running time from 0 to 3600 s, and the vertical axis represents the interlock status indicators from 0 to 6 levels: 0 represents no action, 1 represents feed cut-off, 2 represents heat source shutdown, 3 represents relief valve opening, 4 represents rupture disc activation, 5 represents quenching intervention, and 6 represents relief completion. From the timing evolution, it can be clearly observed that a disturbance input triggers the first-level buffer, the pressure reaches the second-level threshold of 2.25 MPa, and simultaneously enters states 1 and 2. Feed cut-off and heat source shutdown are executed synchronously with a delay of only 36 ms, entering state 3. The relief valve is fully opened, the rupture disc ruptures, entering state 4, the quenching system intervenes, entering state 5, and the pressure drops to a safe value, entering state 6. The entire interlock process has clear logic, a compact timing sequence, and no pauses, delays, or omissions.

[0125] The action node data in the timing diagram correspond perfectly to the discharge response delay in Table 2. The total time from triggering the secondary threshold to fully opening the discharge channel is consistently around 260 ms, with a deviation of no more than 10 ms between each group of tests. This demonstrates that the discharge channel can be opened rapidly within the critical window period of rapid pressure rise, preventing major safety accidents such as equipment rupture or explosion due to overpressure. This fully proves that the rapid interlocking and composite discharge structure of this application has outstanding engineering practical value and safety assurance capabilities. The interlocking action sequence in each group of tests is highly consistent, with no abnormalities such as malfunctions, failures to act, or sequence errors, further verifying the rigor and reliability of the control logic.

[0126] The temperature and concentration comparison data directly confirm the Pur-Eff and HR-Eff in Table 2. In the six groups of tests, the range of the medium outlet temperature and the concentration of harmful components at the outlet did not exceed 3 ℃ and 0.03%, respectively. The high-temperature medium completes the entire process of rapid quenching, full absorption, and efficient gas-liquid separation in the purification and recovery unit. There is no leakage of harmful substances or risk of high-temperature flash explosion. At the same time, liquid phase material circulation and heat energy recovery are achieved, thus achieving the goals of safe release, green environmental protection, and resource reuse.

[0127] Example 3 demonstrates through extreme strong disturbances and multiple sets of parallel repeated tests that this application can still fully execute the entire chain of protection logic, including risk prediction, graded intervention, pre-buffering, rapid discharge, and purification and recycling, under extremely dangerous working conditions, and has high authenticity, reliability and engineering feasibility.

[0128] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any changes, modifications, substitutions, integrations, and parameter changes made to these embodiments within the spirit and principles of the present invention, without departing from the principles and spirit of the present invention, through conventional substitutions or to achieve the same function, fall within the scope of protection of the present invention.

Claims

1. A method for adaptive protection and safe unloading of a chemical plant under over-temperature and over-pressure conditions, characterized in that, The method, applicable to a chemical plant including a reactor, feeding system, cooling system, venting pipeline, and intelligent control unit, comprises: Multi-source heterogeneous data on temperature, pressure, pressure change rate, and concentration of key components inside the reactor are collected in real time, and a pre-trained dynamic risk prediction model is used for data fusion and processing to predict the over-temperature and over-pressure risk level within a preset time window in the future. Based on the predicted risk level, a tiered adaptive proactive intervention strategy is implemented; wherein, When the risk level is a Level 1 warning, the intelligent control unit performs Level 1 parameter compensation by fine-tuning the feeding rate of the feeding system and / or the cooling medium flow rate of the cooling system. When the risk level is a level 2 alarm, the intelligent control unit, based on the first level parameter compensation, simultaneously starts the rapid cooling mode of the reactor jacket or coil, and precisely adjusts the reactant ratio to suppress the reaction rate, thus performing a second level of enhanced intervention. When the internal pressure of the reactor exceeds the first preset threshold but is lower than the second preset threshold, some high-temperature and high-pressure materials or steam are introduced into the pre-buffer unit. The pre-buffer unit includes a shell-and-tube heat exchanger. The heat energy of the material is recovered through the heat exchanger, and its expansion effect is used to reduce the material pressure, thereby achieving source buffering and energy recovery. When the internal pressure of the reactor reaches or exceeds the second preset threshold, or the temperature reaches the safety limit, the intelligent control unit immediately triggers the safety interlock and performs the following actions: Cut off the feeding system and shut down all heating sources; Open the fast-response vent valve installed on the vent pipeline to release the medium in the reactor to the purification and recovery unit.

2. The method according to claim 1, characterized in that, The data fusion and processing using a pre-trained dynamic risk prediction model specifically includes: A risk prediction network based on a spatiotemporal attention mechanism is constructed, which maps the collected multi-source heterogeneous data into high-dimensional feature vectors, and calculates future time moments using the following formula. Comprehensive risk index : ,in, for The input feature vector at time t, Temporal features extracted from Long Short-Term Memory (LSTM) networks. For time step weights calculated based on the attention mechanism, and These are the weight matrix and bias term of the output layer, respectively. Use the Sigmoid activation function; The intelligent control unit will calculate the... Compared with the preset first-level warning threshold and Level 2 alarm threshold Compare these figures to determine the current risk level.

3. The method according to claim 2, characterized in that, When the risk level is a Level 1 warning, the first-level parameter compensation is performed, which specifically includes: The intelligent control unit uses a model predictive control algorithm to calculate the correction amount for the feed rate. To minimize the predicted risk index and the target safety benchmark The deviation between them, and its optimization objective function Build as: ,in, To predict the time domain, To control the time domain, To control the step size, To control the increment, and These are the state error weight matrix and the control increment weight matrix, respectively; The intelligent control unit adjusts the feed pump frequency or regulating valve opening of the feeding system according to the optimal control sequence obtained by solving the objective function.

4. The method according to claim 3, characterized in that, When the risk level is at the Level 2 alert, a Level 2 enhanced intervention will be implemented, specifically including: The intelligent control unit switches the cooling system to rapid cooling mode, adjusts the cooling medium flow rate to its maximum value, and simultaneously calculates the inhibition coefficient of the reactant ratio. ; The inhibition coefficient Based on the instantaneous heat release rate in the reactor With maximum heat transfer capacity The difference is dynamically determined by the formula: ,in, This is the sensitivity coefficient. This refers to the safety margin factor. The intelligent control unit calculates... The value is adjusted by injecting a quencher into the feeding system or reducing the feed ratio of the main reactant.

5. The method according to claim 4, characterized in that, When the internal pressure of the reactor exceeds a first preset threshold but is lower than a second preset threshold, a portion of the high-temperature, high-pressure material or steam is introduced into the pre-buffer unit, specifically including: The shell-and-tube heat exchanger of the pre-buffer unit adopts a counter-current heat exchange method, with high-temperature materials flowing through the tubes and cooling water flowing through the shell. The intelligent control unit is based on the enthalpy value of the material. and target buffer pressure The flow rate of the shell-side cooling water in the shell-and-tube heat exchanger is adjusted in real time. This causes the material outlet temperature to... The phase transition equilibrium condition is satisfied, and the formula is: ,in, Let be the specific heat capacity function of the material. The overall heat transfer coefficient is... For heat exchange area, The logarithmic mean temperature difference This is a reference temperature.

6. The method according to claim 5, characterized in that, The method of utilizing its expansion effect to reduce material pressure specifically includes: The material cooled by the shell-and-tube heat exchanger enters the expansion flash tank, the volume of which is... Based on the maximum discharge mass flow rate and the required gas-liquid separation residence time Design to meet ,in, This refers to the density of the liquid material under buffer pressure. This refers to the volume utilization factor; The expansion flash tank has a gas phase outlet at the top that is connected to the condensation recovery pipeline, and a liquid phase outlet at the bottom that is connected to the collection tank.

7. The method according to claim 6, characterized in that, When the internal pressure of the reactor reaches or exceeds the second preset threshold, or the temperature reaches the safety limit, the fast-response relief valve installed on the relief pipeline is opened, specifically including: The fast-response relief valve adopts a composite structure of a rupture disc and a quick-opening ball valve connected in series. While the intelligent control unit sends an opening signal to the quick-opening ball valve, it also monitors the pressure difference before and after the rupture disc. ; when When the rated burst pressure of the rupture disc is reached, the rupture disc ruptures, and the quick-opening ball valve provides an unobstructed release channel in the fully open state.

8. The method according to claim 7, characterized in that, The process of releasing the medium from the reactor to a purification and recovery unit specifically includes: The outlet end of the vent pipe is connected to a gas distributor, which is submerged below the liquid level of the pre-stored coolant in the buffer tank. The gas distributor is provided with a plurality of micropores, the pore size of which is... Based on the critical Weber number for bubble formation Determine to control bubble diameter This ensures that the bubbles satisfy the following conditions during their ascent: ,in, The surface tension of the coolant, For coolant density, It is the acceleration due to gravity; By controlling the bubble diameter This increases the contact surface area between the high-temperature medium and the coolant, thereby improving the heat and mass exchange efficiency.

9. The method according to claim 8, characterized in that, The purification and recovery unit includes a buffer tank with pre-stored coolant. The outlet of the discharge pipeline is submerged below the surface of the pre-stored coolant to instantly cool and purify the discharged high-temperature medium and harmful components through bubbling quenching and dissolution absorption. The purified gas is discharged after passing through a demister, while the liquid is collected and processed.

10. The method according to claim 9, characterized in that, The purification and recovery unit also includes a demister installed on the gas phase outlet pipeline at the top of the buffer tank; The demister employs a wire mesh trapping structure, and the wire mesh thickness is... and specific surface area Configured to intercept particles larger than a preset threshold. droplets; The gas purified by the demister enters the exhaust gas treatment system. The liquid at the bottom of the buffer tank is drawn out by a circulating pump, cooled by an external plate heat exchanger, and then returned to the top of the buffer tank for spraying, or transported to the waste liquid treatment unit.

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