An adaptive model predictive control system for a mixed plastic pyrolysis process

Abstract

The embodiment relates to the technical field of industrial process control and mixed waste plastic pyrolysis, and particularly relates to a self-adaptive model predictive control system for a mixed plastic pyrolysis process; containing state perception, key energy mapping, enthalpy flow planning and execution feedback unit; the system identifies a chemical reaction dominant type by analyzing a gas generation rate curve; the core is to convert the reaction type into physical energy demand containing energy flow density and action time, generate three-dimensional dynamic enthalpy flow control instructions and self-adaptive switching strategies aiming at the differentiated energy barriers of polyvinyl chloride dechlorination and polyolefin cracking; the application realizes the transformation from single steady-state control to accurate matching of time-space energy potential, and effectively avoids the energy level mismatching problem.

Description

TECHNICAL FIELD

[0001] The embodiment relates to the technical field of industrial process control and mixed waste plastic pyrolysis, and particularly relates to a self-adaptive model predictive control system for a mixed plastic pyrolysis process. BACKGROUND

[0002] In the mixed plastic pyrolysis process, the reaction system covers multiple thermodynamic stages such as polyvinyl chloride dechlorination and polyolefin cracking, and the raw material components usually present dynamic fluctuation characteristics; the existing control scheme generally uses a temperature closed-loop architecture designed for a single steady-state working condition, mainly relying on a PID algorithm to adjust the heating power based on a temperature deviation, trying to maintain a constant reaction temperature environment; however, due to the essential thermodynamic contradiction between the low-temperature long-time environment required by the dechlorination reaction and the high-temperature short-pulse environment required by the cracking reaction, the traditional linear logic cannot perceive the differentiated energy barrier requirement of chemical bond breaking; this mismatch between energy supply and reaction kinetics easily leads to local overheating coking, incomplete reaction, and cannot effectively respond to component disturbance of mixed waste;

[0003] Therefore, how to construct a control mechanism based on the nonlinear matching of energy potential and reaction kinetics, and realize self-adaptive dynamic planning of the fluid enthalpy flow field along with the reaction process, becomes a technical problem to be solved. SUMMARY

[0004] To solve the above technical problems, the present application provides a self-adaptive model predictive control system for a mixed plastic pyrolysis process, in particular, the technical scheme of the present application comprises:

[0005] A multi-component reaction field state perception unit is used to receive real-time gas component concentration data from a gas sensor array; compare the real-time collected gas generation rate curve form with a preset reaction stage feature library; identify the current dominant type of chemical reaction; and generate a reaction stage identification signal;

[0006] A hierarchical bond energy threshold mapping unit is used to receive the reaction stage identification signal; retrieve the required energy characteristics according to a preset polymer thermodynamic database; convert the dominant type of chemical reaction into a physical energy requirement description containing energy flow density and action time; and generate a gradient energy requirement index;

[0007] A composite heat carrier dynamic enthalpy flow planning unit is used to receive the gradient energy requirement index; plan the physical quantity parameters of the heat carrier energy flux vector for a composite heat carrier composed of a high-temperature main heat carrier and a temperature-regulating auxiliary heat carrier; and generate a three-dimensional dynamic enthalpy flow control instruction;

[0008] A reaction progress-potential self-adaptive execution unit is configured to adjust the operating states of the circulating pump, the heater and the double-fluid mixing valve according to the three-dimensional dynamic enthalpy flow control instruction; to monitor the transient thermal response characteristics in the reaction kettle in real time; and to deliver the transient thermal response characteristics as a feedback correction signal to the hierarchical bond energy threshold mapping unit and the composite heat carrier dynamic enthalpy flow planning unit to correct the estimation of the raw material composition.

[0009] Preferably, the multi-component reaction field state sensing unit is specifically configured to:

[0010] The real-time gas component concentration data including hydrogen chloride, light hydrocarbon and aromatic hydrocarbon are acquired.

[0011] Characteristic fingerprint matching logic is adopted.

[0012] When the hydrogen chloride concentration is detected to sharply rise and the light hydrocarbon and the aromatic hydrocarbon concentrations remain low, it is determined that the system is in a dechlorination dominant period.

[0013] The qualitative reaction stage identification signal is generated, and the reaction stage identification signal includes a dechlorination period, a transition period or a cracking period.

[0014] Preferably, the hierarchical bond energy threshold mapping unit generates a gradient energy demand index, specifically including:

[0015] Each polymer bond energy data set in the polymer thermodynamic database is retrieved.

[0016] The instantaneous heat flux intensity required by unit volume of material is determined to define the energy flow density.

[0017] The persistence required to maintain the instantaneous heat flux intensity is determined to define the action time.

[0018] The gradient energy demand index including a low-density-long-time requirement or a high-density-short-pulse requirement is generated.

[0019] Preferably, the physical quantity parameters include:

[0020] Circulating flow rate is used to determine the degree of turbulence and heat exchange coefficient of the composite heat carrier in the jacket or coil;

[0021] Inlet temperature difference, i.e. the difference between the composite heat carrier inlet temperature and the material temperature in the reaction kettle, is used to determine the heat transfer driving force;

[0022] Thermal capacity ratio, determined by the mixing ratio of the high-temperature main heat carrier and the temperature-adjusting auxiliary heat carrier, is used to adjust the overall thermal inertia of the fluid.

[0023] Preferably, the composite heat carrier dynamic enthalpy flow planning unit is specifically configured to:

[0024] When the gradient energy demand index is the low-density-long-term demand, an enthalpy flow mode with high circulation velocity and low inlet temperature difference is planned to improve the heat transfer coefficient and eliminate local high temperature points.

[0025] When the gradient energy demand index is the high-density short-pulse demand, an enthalpy flow mode with low circulation velocity and high inlet temperature difference is planned to utilize the high inlet temperature difference to quickly pass through the pyrolysis endothermic peak.

[0026] Preferably, the reaction process-potential adaptive execution unit adjusts the operating status of the circulating pump, heater, and dual-fluid mixing valve, specifically including:

[0027] Adjust the rotational speed of the circulating pump to control the circulating flow rate;

[0028] The power of the heater is adjusted to control the temperature of the high-temperature main heat carrier, thereby controlling the inlet temperature difference;

[0029] The opening degree of the dual-fluid mixing valve is adjusted to control the mixing ratio of the high-temperature main heat carrier and the temperature-regulating secondary heat carrier, thereby controlling the heat capacity ratio.

[0030] Preferably, the reaction process-potential adaptive execution unit generates a feedback correction signal, specifically including:

[0031] Calculate the ratio of the material temperature change rate to the energy input rate;

[0032] The ratio relationship is defined as the transient thermal response characteristic;

[0033] When the endothermic rate in the monitored transient thermal response characteristics does not match the preset model, it is identified that an unexpected polymer component has been mixed into the raw material.

[0034] Generate the feedback correction signal used to dynamically correct the judgment logic of the hierarchical bond energy threshold mapping unit.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] 1. Existing technologies often lead to energy level mismatch due to single steady-state control. This system uses a multi-component reaction field state sensing unit and a hierarchical bond energy threshold mapping unit to accurately identify the reaction stage using the characteristic fingerprint of the gas generation rate curve. It transforms the chemical reaction type into a physical energy demand description that includes energy flux density and action time. For the low-density-long-aging demand of polyvinyl chloride dechlorination and the high-density-short-pulse demand of polyolefin cracking, the system can adaptively switch control strategies to accurately match the differentiated energy barrier demand of chemical bond breaking in the spatiotemporal dimension, thus avoiding the energy level mismatch problem under traditional linear logic.

[0037] 2. Regarding the local overheating and coking problem mentioned in the background technology, when the dechlorination-dominant period is determined, the dynamic enthalpy flow planning unit of the composite heat carrier automatically plans an enthalpy flow pattern with high circulation velocity and low inlet temperature difference, and coordinates it with a high heat capacity ratio command. This control method significantly improves the heat transfer coefficient by increasing the degree of fluid turbulence, physically limits the maximum temperature of the heat carrier wall by using the low inlet temperature difference, and at the same time uses the large fluid thermal inertia to smooth temperature fluctuations, thereby eliminating local overheating hot spots and effectively preventing the sensitive materials from undergoing unexpected coking or degradation due to excessively high wall temperature.

[0038] 3. To address the issue of incomplete reaction in the background technology, this system plans an enthalpy flow pattern with low circulation velocity and high inlet temperature difference during the cracking-dominant phase, and reduces the heat capacity ratio. This strategy utilizes the huge temperature difference as a strong heat transfer driving force, combined with a lower flow velocity to increase the residence and heat release time of the heat carrier in the heat exchange zone, while reducing the thermal inertia of the fluid to achieve a rapid response to heating power. This allows the system to inject a large amount of endothermic enthalpy change required for the cracking reaction into the material in a very short time, helping the material to quickly overcome the cracking energy barrier, thereby effectively dealing with the endothermic peak and improving oil and gas yield.

[0039] 4. To address the issue of control failure caused by drastic fluctuations in the composition of mixed waste plastic raw materials, the reaction process-energy potential adaptive execution unit of this system introduces an online observation mechanism. By calculating the ratio of the material temperature change rate to the energy input rate in real time, transient thermal response characteristics are monitored. Once a discrepancy is detected between the heat absorption rate and the preset model, the system immediately generates a feedback correction signal to dynamically adjust the judgment logic. This mechanism, based on the physical thermal response to inversely correct the chemical model, endows the system with adaptive capabilities when handling mixed waste with unknown or highly fluctuating components, ensuring the stability of the control process. Attached Figure Description

[0040] The present invention will be further explained below with reference to the accompanying drawings and embodiments:

[0041] Figure 1 This is a structural diagram of the system of the present invention. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0043] Example 1:

[0044] Please see Figure 1 An adaptive model predictive control system for a mixed plastic pyrolysis process includes:

[0045] The multi-component reaction field state sensing unit is used to receive real-time gas component concentration data from the gas sensor array; compare the shape of the real-time gas generation rate curve with the preset reaction stage feature library; identify the current dominant chemical reaction type; and generate reaction stage identification signals.

[0046] The hierarchical bond energy threshold mapping unit is used to receive reaction stage identification signals; retrieve the energy characteristics required for the corresponding reaction based on a preset polymer thermodynamics database; convert the dominant chemical reaction type into a physical energy requirement description including energy flux density and reaction time; and generate gradient energy requirement indicators.

[0047] The composite heat carrier dynamic enthalpy flow planning unit is used to receive gradient energy demand indicators; for the composite heat carrier composed of a high-temperature main heat carrier and a temperature-regulating secondary heat carrier, it plans and determines the physical quantity parameters of the heat carrier energy flux vector; and generates three-dimensional dynamic enthalpy flow control commands.

[0048] The reaction process-potential adaptive execution unit is used to adjust the operating status of the circulating pump, heater and dual-fluid mixing valve according to the three-dimensional dynamic enthalpy flow control command; monitor the transient thermal response characteristics in the reactor in real time; and send the transient thermal response characteristics as feedback correction signals to the graded bond energy threshold mapping unit and the composite heat carrier dynamic enthalpy flow planning unit to correct the prediction of the raw material composition.

[0049] In this embodiment, an adaptive model predictive control system for the pyrolysis process of mixed plastics is constructed. This system, in its industrial process control architecture, abandons the traditional temperature closed-loop logic designed for a single steady-state condition, and instead adopts a dynamic enthalpy-flow control architecture based on nonlinear matching of energy potential and reaction kinetics. It should be noted that the model predictive control in this embodiment does not specifically refer to the rolling optimization algorithm based on infinite time domain in traditional process control, but rather to a discrete event predictive control based on a fingerprint database of chemical reaction kinetics features. Its core lies in using the slope of the gas generation rate at the current moment to predict the type of chemical bond breaking that will occur at the next moment, and accordingly switching the parameter set of the control model in advance. Its core design concept is to resolve the thermodynamic competition between the low-temperature, long-aging environment required for polyvinyl chloride dechlorination and the high-temperature, short-pulse environment required for polyolefin pyrolysis in a continuous flow reactor.

[0050] The multi-component reaction field state sensing unit, as the sensing front end of the system, is configured to analyze the chemical spectrum inside the reactor in real time. This unit receives real-time gas component concentration data from the gas sensor array and performs morphological analysis in the processing logic. It performs pattern matching between the slope changes and peak characteristics of the real-time gas generation rate curve and the preset reaction stage feature library. This step aims to extract the chemical bond breaking type that dominates the current reaction thermodynamic behavior from the complex mixed gas signal, thereby generating a qualitative reaction stage identification signal to clearly indicate whether the system is currently in the dechlorination period, transition period, or cracking period.

[0051] The hierarchical bond energy threshold mapping unit performs the chemical-physical translation function in the system logic. Based on the received reaction stage identification signal, this unit indexes the internal polymer thermodynamic database and extracts the activation energy data required for the corresponding chemical bond breaking. Unlike existing technologies that directly output temperature setpoints, this unit transforms the dominant chemical reaction type into a physical energy demand description that includes energy flux density and reaction time, generating a gradient energy demand index. This process realizes the quantitative mapping between energy supply strategies and chemical bond energy characteristics.

[0052] The composite heat carrier dynamic enthalpy flow planning unit serves as the core control hub, performing multi-dimensional planning of the fluid medium based on gradient energy demand indicators. For composite heat carriers composed of a high-temperature primary heat carrier and a temperature-regulating secondary heat carrier, this unit uses algorithms to plan and determine three key physical parameters of the heat carrier energy flux vector: circulation velocity, inlet temperature difference, and heat capacity ratio. The generated three-dimensional dynamic enthalpy flow control command aims to construct a fluid enthalpy flow field that deforms in real time with the reaction stage, so as to accurately match the energy barrier requirements for chemical bond breaking in the spatiotemporal dimension, avoiding local overheating and coking or incomplete reaction caused by energy level mismatch.

[0053] The reaction process-potential adaptive execution unit is responsible for the closed-loop execution and model calibration of the physical layer. On the execution side, this unit coordinates the operation of the circulating pump, heater, and dual-fluid mixing valve according to control commands. On the feedback side, this unit monitors the transient thermal response characteristics in the reactor in real time, that is, the dynamic response rate of material temperature to energy input. Once the response characteristics deviate from the preset model, the unit immediately generates a feedback correction signal and sends it to the preceding unit to dynamically correct the estimated parameters of the raw material composition. This mechanism gives the system the ability to adapt to mixed waste with drastic fluctuations in composition.

[0054] Example 2:

[0055] The multi-component reaction field state sensing unit is specifically used for:

[0056] Acquire real-time concentration data of gas components, including hydrogen chloride, light hydrocarbons, and aromatics;

[0057] Employ feature fingerprint matching logic;

[0058] When a sharp increase in hydrogen chloride concentration is detected while the concentrations of light hydrocarbons and aromatic hydrocarbons remain low, the system is determined to be in the dechlorination-dominant phase.

[0059] Generate qualitative reaction stage identification signals, including dechlorination period, transition period, or pyrolysis period.

[0060] In this specific embodiment, the operating logic of the multi-component reaction field state sensing unit is refined into an identification process for specific gas fingerprints; the unit acquires multi-channel gas component concentration data, including hydrogen chloride, light hydrocarbons and aromatics, in real time; at the data processing level, the unit adopts feature fingerprint matching logic, which presets kinetic feature templates for the pyrolysis of different polymers.

[0061] In the specific judgment operation, the system sets a change rate threshold and a relative concentration benchmark, and introduces a time series prediction algorithm to compensate for gas transport lag. When the monitoring data shows that the time derivative of hydrogen chloride concentration exceeds the preset surge threshold, and the proportion of light hydrocarbon and aromatic hydrocarbon generation rates in the total gas generation is lower than the preset overlap factor, the logic core determines that the chemical bond breaking event in the current reaction system is mainly dominated by the removal of polyvinyl chloride side groups. Specifically, a sharp rise means that the real-time change rate of hydrogen chloride concentration exceeds 50 ppm / s, or the mole fraction of hydrogen chloride in the total gas products jumps from the baseline value to more than 40% within 30 seconds; the low concentration of light hydrocarbon and aromatic hydrocarbons means that the combined generation rate of light hydrocarbons and aromatic hydrocarbons accounts for less than 5% of the total gas generation rate by mass.

[0062] Accordingly, the system locks the current state and generates a reaction stage identifier signal indicating the dechlorination-dominant period; similarly, if a jump in light hydrocarbon concentration and a drop in hydrogen chloride concentration are detected, a signal indicating the cracking period is generated; this reverse deduction mechanism based on product generation enables the control system to accurately segment different thermodynamic stages in the continuous reaction process, providing a precise time axis trigger source for segmented temperature control.

[0063] Example 3:

[0064] The hierarchical bond energy threshold mapping unit generates gradient energy demand indices, specifically including:

[0065] Retrieve the set of bond energy data for each polymer in the polymer thermodynamics database;

[0066] Determine the instantaneous heat flux required per unit volume of material to define the energy flux density;

[0067] Determine the duration required to maintain the instantaneous heat flux intensity to define the duration of action;

[0068] Generate gradient energy demand indices that include either low-density, long-duration demand or high-density, short-pulse demand.

[0069] This embodiment details how the hierarchical bond energy threshold mapping unit constructs a physical energy demand model; after receiving the stage signal, the unit searches the polymer thermodynamics database to obtain standard dissociation enthalpy data for low C-Cl bond energy or high C-C bond energy;

[0070] Based on this, the unit does not directly calculate the heating power, but combines the current material processing flow rate and the estimated reaction rate to define two orthogonal control dimensions: energy flux density, which is calculated as the reaction enthalpy change requirement per unit time and unit volume, used to characterize the instantaneous heat flux intensity required to penetrate the reaction energy barrier, i.e., the 'force' required to overcome the reaction energy barrier; and action time, which is determined as the duration required to maintain the instantaneous heat flux intensity, used to characterize the process required to complete the reaction conversion.

[0071] Based on the above definitions, the unit generates gradient energy demand indicators. For example, for dechlorination reactions, the system generates low-density-long-aging demand indicators to simulate the thermal environment of slow cooking. For pyrolysis reactions, it generates high-density-short-pulse demand indicators to simulate the thermal environment of high-heat stir-frying. This deconstruction of energy demand into a two-dimensional indicator of density and aging breaks the linear logic of traditional PID control that only focuses on the difference between the current temperature and the set temperature, and realizes a deep response to the reaction kinetics demand.

[0072] Example 4:

[0073] Physical quantity parameters include:

[0074] The circulation velocity is used to determine the degree of turbulence and heat transfer coefficient of the composite heat transfer fluid in the jacket or coil.

[0075] The inlet temperature difference, which is the difference between the inlet temperature of the composite heat carrier and the temperature of the material inside the reactor, is used to determine the driving force for heat transfer.

[0076] The heat capacity ratio is determined by the mixing ratio of the high-temperature primary heat carrier and the temperature-regulating secondary heat carrier, and is used to adjust the overall thermal inertia of the fluid.

[0077] The composite heat carrier dynamic enthalpy flow planning unit is specifically used for:

[0078] When the gradient energy demand index is low density-long duration demand, plan an enthalpy flow mode with high circulation velocity and low inlet temperature difference to improve the heat transfer coefficient and eliminate local high temperature points.

[0079] When the gradient energy demand index is a high-density, short-pulse demand, an enthalpy flow mode with low circulation velocity and high inlet temperature difference is planned to take advantage of the high inlet temperature difference to quickly pass through the pyrolysis endothermic peak.

[0080] Specific parameter planning examples are as follows: During the dechlorination period, the circulation flow rate is controlled at 2.5-3.0 m / s, and the inlet temperature difference is controlled at 10℃-15℃; during the pyrolysis period, the circulation flow rate is controlled to decrease to 0.8-1.2 m / s, while the inlet temperature difference is increased to 80℃-120℃ to form a strong driving force thermal front.

[0081] Regarding the heat capacity ratio, the composite heat carrier dynamic enthalpy-flow planning unit performs the following planning: When the gradient energy demand index is low-density-long-term demand, the planning unit generates a high heat capacity ratio instruction, that is, increases the mass proportion of the temperature-regulating auxiliary heat carrier in the mixed fluid, thereby using the larger overall fluid thermal inertia to smooth temperature fluctuations and prevent local coking of sensitive dechlorination reactions due to instantaneous overshoot of the heater; when the gradient energy demand index is high-density-short-pulse demand, the planning unit generates a low heat capacity ratio instruction, that is, reduces the proportion of the temperature-regulating auxiliary heat carrier and reduces the fluid thermal inertia, so as to achieve a rapid response of the heat carrier to the heater power change and ensure the instantaneous breakthrough of the barrier energy barrier;

[0082] In this embodiment, the temperature-regulating auxiliary heat carrier is drawn from a constant-temperature buffer circuit with a large-volume storage tank, and its temperature fluctuation rate is less than 0.1℃ / min, thus it is considered a high thermal inertia source; the high-temperature main heat carrier is directly drawn from the heater outlet, and its temperature responds quickly to power adjustments, thus it is considered a low thermal inertia source. The overall thermal inertia of the regulating fluid refers to the response time constant of the mixed fluid outlet temperature to heater power fluctuations by adjusting the mixing mass ratio of the two.

[0083] This embodiment elaborates on how the composite heat carrier dynamic enthalpy flow planning unit meets the above-mentioned energy requirements by regulating the physical properties of the fluid; the physical parameters selected by the unit have clear thermodynamic significance: the circulation velocity is directly related to the Reynolds number, which determines the thickness of the boundary layer and the convective heat transfer coefficient; the inlet temperature difference provides the potential energy difference to drive the flow of heat; and the heat capacity ratio adjusts the system's ability to suppress temperature fluctuations by changing the average specific heat capacity of the fluid medium.

[0084] In the specific implementation of the control strategy, when facing the demand for low density and long aging, i.e. dechlorination period, the planning unit constructs a high circulation flow rate and low inlet temperature difference mode. In this mode, the high flow rate leads to violent turbulence, which greatly improves the heat transfer coefficient, so that effective heat input can be maintained even at extremely low temperature difference. The core advantage of this strategy is that it uses the low inlet temperature difference to physically limit the maximum temperature of the heat carrier wall, thereby eliminating local hot spots and effectively preventing PVC from undergoing unexpected coking or degradation due to excessive wall temperature.

[0085] Conversely, when facing high-density, short-pulse demand, i.e., the pyrolysis period, the planning unit switches to a low circulation flow rate and high inlet temperature difference mode. This mode utilizes the huge temperature difference as a strong heat transfer driving force, combined with a lower flow rate to increase the residence and heat release time of the heat carrier in the heat exchange zone, thereby injecting a large amount of endothermic enthalpy change required for the pyrolysis reaction into the material in a very short time, helping the material to quickly overcome the pyrolysis energy barrier and improve oil and gas yield. It should be noted that although the low circulation flow rate will reduce the convective heat transfer coefficient to some extent, the huge heat transfer driving force provided by the extremely high inlet temperature difference can effectively compensate for the decline in the convective heat transfer coefficient, ensuring that the total heat flux reaches the high-density requirement required for the pyrolysis endothermic peak in a short time. Therefore, the core of this strategy is to use the temperature difference driving force to achieve efficient injection of energy in short pulses.

[0086] Example 5:

[0087] The reaction process – the adaptive energy potential actuator – regulates the operating status of the circulating pump, heater, and dual-fluid mixing valve, specifically including:

[0088] Adjust the speed of the circulating pump to control the circulation flow rate;

[0089] Adjusting the power of the heater controls the temperature of the high-temperature main heat carrier, thereby controlling the inlet temperature difference;

[0090] Adjusting the opening of the dual-fluid mixing valve controls the mixing ratio of the high-temperature main heat carrier and the temperature-regulating secondary heat carrier, thereby controlling the heat capacity ratio.

[0091] In this embodiment, the reaction process-potential adaptive execution unit establishes a mapping relationship from algorithm instructions to hardware actions; the system adjusts the speed of the circulating pump through a frequency converter to achieve continuous adjustment of the mass flow rate and velocity of the heat carrier, directly intervening in the Reynolds number of the fluid; by adjusting the power of the heater, such as the thyristor voltage regulation of the electric heater or the fuel quantity of the burner, the outlet temperature of the high-temperature main heat carrier is changed, thereby precisely controlling the inlet temperature difference under the premise that the material temperature is relatively stable;

[0092] In addition, the unit adjusts the opening of the dual-fluid mixing valve through a servo mechanism; the valve mixes the high-temperature fluid from the heater with the temperature-regulating auxiliary heat carrier from the cooling circuit or bypass in a proportional manner; by changing the mixing ratio of the two fluids, the system can synthesize a composite heat carrier with a specific temperature and thermal inertia in real time; this coordinated adjustment of multiple actuators enables the control system to flexibly adapt to various chemical reaction conditions by reconstructing the fluid morphology without changing the main structure of the reactor.

[0093] Example 6:

[0094] The reaction process—the adaptive energy potential execution unit generates feedback correction signals, specifically including:

[0095] Calculate the ratio of the material temperature change rate to the energy input rate;

[0096] The ratio relationship is defined as a transient thermal response characteristic;

[0097] When the endothermic rate in the monitored transient thermal response characteristics does not match the preset model, it is identified that an unexpected polymer component has been mixed into the raw material.

[0098] Generate feedback correction signals for dynamically correcting the decision logic of the hierarchical bond energy threshold mapping unit.

[0099] This embodiment describes the system's adaptive calibration mechanism; the reaction process-potential adaptive execution unit runs an online observer while performing control; the observer calculates in real time the ratio between the time derivative of the material temperature and the current input net energy flow rate, and defines this ratio as the transient thermal response characteristic; this characteristic physically characterizes the real-time apparent heat capacity and endothermic / exothermic rate of the reaction system;

[0100] In the monitoring logic, the system performs residual analysis on the measured transient thermal response characteristics and the standard model of the current reaction stage. If an endothermic rate far exceeding the expectation is detected in the stage determined to be the dechlorination period, the system will identify that the raw material may have been mixed with unexpected low-melting-point polymer components that have prematurely decomposed. Based on this identification, the unit generates a feedback correction signal and sends it to the front-end mapping unit to dynamically adjust the subsequent energy density threshold or switch the judgment logic. The feedback correction signal is also sent to the composite heat carrier dynamic enthalpy flow planning unit to dynamically fine-tune the control parameters of the planning unit, such as adjusting the enthalpy flow mode switching sensitivity or proportional-integral-derivative gain of the current stage. This closed-loop correction mechanism ensures that when the system is dealing with mixed waste plastics with unknown or fluctuating composition, it can correct the chemical model in reverse through physical thermal response, maintaining the robustness and accuracy of the control strategy.

[0101] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. An adaptive model predictive control system for a mixed plastic pyrolysis process, characterized in that, include: A multi-component reaction field state sensing unit is used to receive real-time gas component concentration data from a gas sensor array; The shape of the gas generation rate curve collected in real time is compared with the preset reaction stage feature library to identify the dominant type of the current chemical reaction. Generate reaction stage identification signals; A hierarchical bond energy threshold mapping unit is used to receive the reaction stage identification signal; retrieve the energy characteristics required for the corresponding reaction according to a preset polymer thermodynamics database; and convert the dominant type of the chemical reaction into a physical energy requirement description that includes energy flux density and reaction time. Generate gradient energy requirement indicators; The composite heat carrier dynamic enthalpy flow planning unit is used to receive the gradient energy demand index; for the composite heat carrier composed of a high-temperature main heat carrier and a temperature-regulating secondary heat carrier, it plans and determines the physical quantity parameters of the heat carrier energy flux vector; and generates three-dimensional dynamic enthalpy flow control commands. The reaction process-potential adaptive execution unit is used to adjust the operating status of the circulating pump, heater and dual-fluid mixing valve according to the three-dimensional dynamic enthalpy flow control command; monitor the transient thermal response characteristics in the reactor in real time; and send the transient thermal response characteristics as feedback correction signals to the graded bond energy threshold mapping unit and the composite heat carrier dynamic enthalpy flow planning unit to correct the prediction of the raw material composition.

2. The adaptive model predictive control system for the pyrolysis process of mixed plastics according to claim 1, characterized in that, The multi-component reaction field state sensing unit is specifically used for: Acquire real-time concentration data of the gas components, including hydrogen chloride, light hydrocarbons, and aromatics; Employ feature fingerprint matching logic; When a sharp increase in the concentration of hydrogen chloride is detected while the concentrations of light hydrocarbons and aromatic hydrocarbons remain low, the system is determined to be in the dechlorination-dominant phase. Generate qualitative reaction stage identification signals, including dechlorination period, transition period, or pyrolysis period.

3. The adaptive model predictive control system for the pyrolysis process of mixed plastics according to claim 1, characterized in that, The hierarchical bond energy threshold mapping unit generates a gradient energy demand index, specifically including: Retrieve the set of polymer bond energy data from the polymer thermodynamics database; Determine the instantaneous heat flux required per unit volume of material to define the energy flux density; The duration required to maintain the instantaneous heat flux intensity is determined to define the duration of action; Generate the gradient energy demand index that includes either low-density, long-duration demand or high-density, short-pulse demand.

4. An adaptive model predictive control system for a mixed plastic pyrolysis process according to claim 3, characterized in that, The physical quantity parameters include: The circulation velocity is used to determine the degree of turbulence and heat transfer coefficient of the composite heat transfer fluid in the jacket or coil. The inlet temperature difference, which is the difference between the inlet temperature of the composite heat carrier and the temperature of the material inside the reactor, is used to determine the heat transfer driving force. The heat capacity ratio is determined by the mixing ratio of the high-temperature main heat carrier and the temperature-regulating secondary heat carrier, and is used to adjust the overall thermal inertia of the fluid.

5. An adaptive model predictive control system for a mixed plastic pyrolysis process according to claim 4, characterized in that, The composite heat carrier dynamic enthalpy flow planning unit is specifically used for: When the gradient energy demand index is the low-density-long-term demand, an enthalpy flow mode with high circulation velocity and low inlet temperature difference is planned to improve the heat transfer coefficient and eliminate local high temperature points. When the gradient energy demand index is the high-density short-pulse demand, an enthalpy flow mode with low circulation velocity and high inlet temperature difference is planned to utilize the high inlet temperature difference to quickly pass through the pyrolysis endothermic peak.

6. An adaptive model predictive control system for a mixed plastic pyrolysis process according to claim 4, characterized in that, The reaction process-potential adaptive execution unit regulates the operating status of the circulating pump, heater, and dual-fluid mixing valve, specifically including: Adjust the rotational speed of the circulating pump to control the circulating flow rate; The power of the heater is adjusted to control the temperature of the high-temperature main heat carrier, thereby controlling the inlet temperature difference; The opening degree of the dual-fluid mixing valve is adjusted to control the mixing ratio of the high-temperature main heat carrier and the temperature-regulating secondary heat carrier, thereby controlling the heat capacity ratio.

7. An adaptive model predictive control system for a mixed plastic pyrolysis process according to claim 1, characterized in that, The reaction process-potential adaptive execution unit generates a feedback correction signal, specifically including: Calculate the ratio of the material temperature change rate to the energy input rate; The ratio relationship is defined as the transient thermal response characteristic; When the endothermic rate in the monitored transient thermal response characteristics does not match the preset model, it is identified that an unexpected polymer component has been mixed into the raw material. Generate the feedback correction signal used to dynamically correct the judgment logic of the hierarchical bond energy threshold mapping unit.

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