A numerical simulation method, device and equipment for carbon dioxide resource reaction

Abstract

The application relates to the field of carbon dioxide resource utilization, and discloses a numerical simulation method, device and equipment for a carbon dioxide resource utilization reaction, wherein the method comprises the following steps: a flow field simulation model and a reaction simulation model of the carbon dioxide resource utilization reaction are established; reaction component concentration and a reaction rate are obtained; based on the reaction component concentration, the flow field simulation model is analyzed in a steady state to determine stable flow field data of the resource utilization reaction; based on the reaction rate and the stable flow field data, equivalent stable time of the resource utilization reaction is determined; based on the reaction rate and the equivalent stable time, the reaction component concentration is corrected; based on the corrected reaction component concentration and the stable flow field data, the reaction simulation model is analyzed in a transient state until the resource utilization reaction ends, so that a numerical simulation result of the resource utilization reaction process is obtained. The technical scheme provided by the application can improve the simulation accuracy and simulation efficiency of the numerical simulation process for carbon dioxide resource utilization.

Description

Technical Field

[0001] This application relates to the field of numerical simulation technology, and in particular to a numerical simulation method, apparatus and equipment for carbon dioxide resource recovery reaction. Background Technology

[0002] Gas-liquid mass transfer reaction technologies, such as carbon dioxide resource utilization, are key research and development directions in the fields of chemical engineering, energy, and environment. These technologies convert carbon dioxide into chemicals, such as methanol, cyclic carbonates, and formic acid, through two-phase gas-liquid reactions. Specifically, the aforementioned carbon dioxide resource utilization reaction process involves the mass transfer of carbon dioxide from the gas phase to the liquid phase, as well as the chemical reactions that occur in the liquid phase.

[0003] In related technologies, numerical simulation strategies are commonly used to analyze and quantify carbon dioxide resource recovery reactions. For example, strategies based on fully coupled transient simulation or fully coupled steady-state simulation are used to numerically simulate the aforementioned carbon dioxide resource recovery reactions. However, in the above simulation process, although transient simulation can completely describe the transient evolution of mass transfer and reaction processes, its simulation efficiency is relatively slow. While steady-state simulation can quickly obtain simulation results of the flow field, it cannot provide information on the evolution of the reaction process over time, resulting in lower simulation accuracy.

[0004] Therefore, how to improve the simulation efficiency of carbon dioxide resource recovery processes while ensuring the accuracy of numerical simulation has become an urgent problem to be solved. Summary of the Invention

[0005] This application provides a numerical simulation method, apparatus, and equipment for carbon dioxide resource recovery reactions. It can perform efficient and accurate numerical simulation of carbon dioxide resource recovery reaction processes by rapidly determining a stable flow field containing mass transfer and reaction characteristics without relying on long-term transient calculations.

[0006] The first aspect of this application provides a numerical simulation method for carbon dioxide resource recovery reactions. The method involves establishing a numerical simulation model of the carbon dioxide resource recovery reaction, wherein the numerical simulation model includes a flow field simulation model and a reaction simulation model, the numerical simulation model being determined based on a preset equivalent reaction source term; obtaining the concentration of reaction components and the reaction rate; performing steady-state analysis on the flow field simulation model based on the reaction component concentrations to determine the stable flow field data of the resource recovery reaction; determining the equivalent settling time of the resource recovery reaction based on the reaction rate and the stable flow field data; correcting the concentration of reaction components based on the reaction rate and the equivalent settling time; and performing transient analysis on the reaction simulation model based on the corrected reaction component concentrations and the stable flow field data until the resource recovery reaction ends, thereby obtaining the numerical simulation results of the resource recovery reaction process.

[0007] In one embodiment, establishing a numerical simulation model for a carbon dioxide resource recovery reaction includes: establishing a three-dimensional geometric model of the reactor for the resource recovery reaction; establishing a flow field simulation model based on the three-dimensional geometric model, wherein the flow field simulation model includes at least a multiphase flow model, the multiphase flow model being established based on a preset equivalent reaction source term; and establishing a reaction simulation model based on the three-dimensional geometric model, wherein the reaction simulation model includes a component transport equation and a first scalar transport equation, the first scalar transport equation being established based on a preset equivalent reaction source term.

[0008] In one embodiment, the flow field simulation model includes at least a multiphase flow model, which includes a momentum equation, a continuity equation, and a first scalar transport equation. Steady-state analysis of the flow field simulation model based on the concentration of the reactants to determine the stable flow field data of the resource recovery reaction includes: analyzing the momentum equation, continuity equation, and first scalar transport equation based on the concentration of the reactants to obtain the stable flow field data; wherein the concentration of the reactants is the reference concentration of each reactant in the resource recovery reaction, and the first scalar transport equation is established based on a preset equivalent reaction source term.

[0009] In one embodiment, the equivalent reaction source term includes a gas-liquid mass transfer source term and a reaction consumption source term; wherein: the gas-liquid mass transfer source term is determined based on fluid dynamics conditions, and the gas-liquid mass transfer source term is used to characterize the coupling effect of gas-liquid mass transfer on carbon dioxide dissolved concentration; and the reaction consumption source term is determined based on reaction kinetics conditions, and the reaction consumption source term is used to characterize the coupling effect of chemical reaction on carbon dioxide dissolved concentration.

[0010] In one embodiment, the stable flow field data includes flow field parameters and dissolved carbon dioxide concentration; determining the equivalent settling time of the resource recovery reaction based on the reaction rate and the stable flow field data includes: determining the current survival time increment based on the flow field parameters and the dissolved carbon dioxide concentration, and presetting the current survival time reduction based on the reaction rate; determining the equivalent settling time of the resource recovery reaction based on the survival time increment, the survival time reduction, and the flow field parameters.

[0011] In one embodiment, the concentration of the reaction component is the concentration of each reaction component in the resource recovery reaction, and the reaction component includes a reaction substrate and a target product. Correcting the concentration of the reaction component based on the reaction rate and the equivalent stabilization time includes: obtaining a first stoichiometric coefficient of the reaction substrate and a second stoichiometric coefficient of the target product; determining a first concentration correction amount for the reaction substrate based on the first stoichiometric coefficient, the reaction rate, and the equivalent stabilization time; and correcting the concentration of the reaction substrate based on the first concentration correction amount. Finally, determining a second concentration correction amount for the target product based on the second stoichiometric coefficient, the reaction rate, and the equivalent stabilization time; and correcting the concentration of the target product based on the second concentration correction amount.

[0012] In one embodiment, transient analysis of the reaction simulation model based on the corrected reaction component concentration and the stable flow field data includes: iterative analysis of the reaction simulation model using the corrected reaction component concentration and the stable flow field data as reaction conditions; in any iteration of the iterative analysis, determining the transient reaction component concentration of the reaction simulation model in the current iteration, judging whether the reaction simulation model meets the flow field update conditions based on the transient reaction component concentration, and if it is determined that the reaction simulation model does not meet the flow field update conditions, using the transient reaction component concentration as the numerical simulation result of the current iteration, and using the transient reaction component concentration and the stable flow field data as the reaction conditions for the next iteration.

[0013] In one embodiment, when the reaction simulation model is determined to meet the flow field update conditions, the method further includes: pausing the iterative analysis, determining the transient reaction rate at the current moment based on the transient reaction component concentration; updating the stable flow field data based on the transient reaction component concentration and the transient reaction rate to obtain updated flow field data; using the transient reaction component concentration as the numerical simulation result of the current iteration, and continuing the iterative analysis with the transient reaction component concentration and the updated flow field data as the reaction conditions.

[0014] A second aspect of this application provides a numerical simulation apparatus for a carbon dioxide resource recovery reaction. The apparatus includes: a model building unit for building a numerical simulation model of the carbon dioxide resource recovery reaction, wherein the numerical simulation model includes a flow field simulation model and a reaction simulation model, the numerical simulation model being determined based on a preset equivalent reaction source term; a steady-state determination unit for acquiring the concentration of the reaction components and the reaction rate, and performing steady-state analysis on the flow field simulation model based on the concentration of the reaction components to determine the stable flow field data of the resource recovery reaction; a concentration correction unit for determining the equivalent settling time of the resource recovery reaction based on the reaction rate and the stable flow field data, and correcting the concentration of the reaction components based on the reaction rate and the equivalent settling time; and a transient analysis unit for performing transient analysis on the reaction simulation model based on the corrected concentration of the reaction components and the stable flow field data until the resource recovery reaction ends, to obtain the numerical simulation results of the resource recovery reaction process.

[0015] A third aspect of this application provides a computer device, a memory, and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to perform a numerical simulation method for carbon dioxide resource recovery reaction as described in the first aspect above.

[0016] Based on the above ideas, the technical solution provided in this embodiment of the application performs alternating steady-state and transient solutions based on equivalent reaction source terms, combined with equivalent time compensation of physical reaction concentrations, thereby achieving efficient and accurate simulation of the carbon dioxide resource recovery reaction process. Specifically, the acquisition of the steady flow field is changed from relying on real physical time progression to direct steady-state solution, significantly reducing the computation time of this stage; through the equivalent time compensation mechanism, it is ensured that the component concentration distribution at the starting point of the transient calculation conforms to physical facts, avoiding the loss of reaction history; the transient solution after freezing the flow field can use a larger time step, further improving the simulation efficiency of long-cycle reaction processes, thereby achieving a significant reduction in computational cost and an improvement in simulation efficiency while ensuring simulation accuracy.

[0017] It is evident that the technical solution provided in this application can achieve efficient and accurate numerical simulation of the carbon dioxide resource utilization reaction process. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific 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 from these drawings without creative effort.

[0019] Figure 1 A schematic diagram illustrating the steps of a numerical simulation method for carbon dioxide resource recovery provided in this application embodiment;

[0020] Figure 2 A schematic diagram illustrating the steps of a numerical simulation method for carbon dioxide resource recovery reaction provided in one embodiment of this application;

[0021] Figure 3(a) is a schematic diagram of a stirred reactor provided in one embodiment of this application;

[0022] Figure 3(b) is a schematic diagram of the mesh generation of a stirred reaction model provided in an embodiment of this application;

[0023] Figure 4 A flow field distribution cloud map of carbon dioxide dissolved concentration is provided as an embodiment of this application;

[0024] Figure 5 A schematic diagram of the spatial distribution of equivalent settling time provided in one embodiment of this application;

[0025] Figure 6 A schematic diagram of the structure of a numerical simulation device for carbon dioxide resource recovery reaction provided in one embodiment of this application;

[0026] Figure 7 This is a schematic diagram of the structure of a computer device provided in one embodiment of this application. Detailed Implementation

[0027] 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 described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] Furthermore, the use of terms such as "first," "second," etc., in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of embodiments in this application, unless otherwise stated, "multiple" means two or more. Additionally, the use of "based on" or "according to" implies openness and inclusiveness, because processes, steps, calculations, or other actions "based on" or "according to" one or more of the stated conditions or values ​​may in practice be based on additional conditions or beyond the stated values.

[0029] The application of gas-liquid mass transfer reaction technologies, such as carbon dioxide resource recovery, has become a key research and development direction in the chemical, energy, and environmental fields. These technologies convert carbon dioxide into chemicals such as methanol and cyclic carbonates through two-phase gas-liquid reactions. Typically, carbon dioxide resource recovery processes are conducted in multiphase reactors such as bubble columns and stirred tanks. These processes involve the flow of carbon dioxide gaseous injection, mass transfer of carbon dioxide from the gas phase to the liquid phase, and chemical reactions of carbon dioxide in the liquid phase. This is a complex system characterized by multiphase coexistence, complex reaction pathways, and strong coupling between gas-liquid mass transfer and chemical reactions. To analyze and optimize these complex processes, numerical simulation strategies are commonly used to analyze the carbon dioxide resource recovery reaction process, obtaining the spatiotemporal distribution of multiple physical fields such as flow field, concentration field, and temperature field during the reaction, as well as the coupling mechanism between mass transfer and reaction.

[0030] In traditional techniques, the aforementioned numerical simulation strategies typically include fully coupled transient simulation and fully coupled steady-state simulation. In fully coupled transient simulation, the flow, mass transfer, and reaction equations are solved simultaneously over time, providing a complete description of the transient evolution of the process. However, due to the significant differences in the timescales of the flow, mass transfer, and reaction processes—that is, the gas-liquid mass transfer reaction system exhibits multi-timescale characteristics—the computational step size is limited to the fastest flow field change, i.e., a uniform minimum time step (flow field change step size) is used, resulting in low simulation efficiency and high computational costs. On the other hand, fully coupled steady-state simulation struggles to capture the dynamic equilibrium establishment process of gas-liquid mass transfer and reaction rates in the initial stages of the reaction. Furthermore, the steady-state solution itself directly approaches the system's reaction equilibrium endpoint, failing to provide information on the time-varying evolution of the reaction process, leading to poor simulation accuracy.

[0031] In related technologies, a distributed transient solution strategy has been proposed. This strategy involves performing a fully coupled transient simulation for a period of time. Once the flow field stabilizes, it is frozen, and a larger time step is used to simulate the mass transfer and reaction equations, thus decoupling the flow field state from mass transfer and reaction. This approach can accelerate the simulation process of mass transfer and reaction to some extent, but it still has drawbacks. Specifically, because the mass transfer efficiency of carbon dioxide dissolution affects the dissolved concentration, and the dissolved concentration is related to the chemical reaction, the mass transfer and reaction processes are coupled. Furthermore, the gas dissolution and consumption caused by mass transfer and reaction also interact with the flow field structure. Therefore, the prerequisite for flow field stability is that mass transfer and reaction reach equilibrium, which often requires a large time scale, necessitating a relatively long fully coupled transient simulation. In addition, the above method stops monitoring the flow field once it stabilizes. When subsequent mass transfer and reaction processes affect the flow field structure, updates cannot be made, resulting in low accuracy and efficiency in the numerical simulation of carbon dioxide resource recovery reactions.

[0032] In view of this, one or more embodiments of this application provide a numerical simulation method for carbon dioxide resource recovery reaction, which can solve the above problems. Without relying on long-term transient calculations, it can quickly determine a stable flow field containing mass transfer and reaction characteristics, thereby performing efficient and accurate numerical simulation of the carbon dioxide resource recovery reaction process and improving the simulation accuracy and efficiency of numerical simulation processes for carbon dioxide resource recovery.

[0033] Please see Figure 1 One embodiment of this application provides a numerical simulation method for carbon dioxide resource recovery reactions, which may include the following steps:

[0034] S1: Establish a numerical simulation model for the carbon dioxide resource recovery reaction, wherein the numerical simulation model includes a flow field simulation model and a reaction simulation model, and the numerical simulation model is determined based on a preset equivalent reaction source term.

[0035] Due to the multi-timescale characteristics of gas-liquid mass transfer reaction systems, the flow field simulation model and the reaction simulation model are designed separately to employ differentiated solution strategies for different processes. The flow field simulation model describes the gas-liquid two-phase flow state within the reactor, reflecting the "flow" conditions of the carbon dioxide resource recovery reaction. It typically includes momentum equations, continuity equations, and auxiliary equations describing turbulence and bubble swarm behavior, used to calculate flow field parameters such as velocity, pressure, and gas phase volume fraction. The reaction simulation model describes the mathematical model of component concentration changes during the chemical reaction process, reflecting the "chemical reaction" conditions of the carbon dioxide resource recovery reaction.

[0036] The aforementioned equivalent reaction source terms can be composite structures based on fluid dynamics conditions, reaction kinetics conditions, etc., and are typically embedded in the numerical simulation model as source terms. These equivalent reaction source terms are used to reflect the coupled effects of gas-liquid mass transfer and chemical reactions on carbon dioxide dissolved concentration in steady-state solutions, thus equivalently representing the dynamic equilibrium state of gas-liquid mass transfer and chemical reactions. Compared to traditional transient and steady-state calculations, by setting equivalent reaction source terms in steady-state calculations, the steady-state solver can obtain a reasonable stable flow field without tracking real-time evolution, thereby acquiring stable flow field data more quickly and accurately.

[0037] S3: Obtain the concentration of the reaction components and the reaction rate. Based on the concentration of the reaction components, perform steady-state analysis on the flow field simulation model to determine the stable flow field data of the resource recovery reaction.

[0038] The above-mentioned reaction component concentrations refer to the concentrations of each reaction component during the carbon dioxide resource recovery process. These reaction components include the reaction substrate and the target product; for example, styrene oxide is used as the reaction substrate, and styrene carbonate is the corresponding target product. It should be noted that the above-mentioned reaction component concentrations do not include the dissolved carbon dioxide concentration. During the initial execution, the reaction component concentrations are taken as the initial unreacted concentrations, and the reaction rate is calculated based on this initial state. The above-mentioned reaction rate is the amount of reactant consumed or product generated per unit time, determined by the reaction kinetic equation, and is usually a function of the reaction component concentration and the dissolved carbon dioxide concentration. The above-mentioned steady-state flow field data can be understood as a set of parameters including gas-liquid phase velocity, pressure distribution, gas phase volume fraction, and dissolved carbon dioxide concentration, taken at the equilibrium state of the flow field.

[0039] In this embodiment, a flow field simulation model is configured based on the concentration of reacting components, and steady-state analysis is performed on the model. The concentration of reacting components is used to determine liquid phase physical properties (density, viscosity, etc.), which directly affect the coefficients in the flow field simulation model. The steady-state analysis process uses a steady-state solver to solve the flow field simulation model to determine a quasi-steady-state flow field that matches the current chemical reaction state, ignoring actual physical time evolution. Compared to traditional transient propagation, this method can determine stable flow field data more quickly. Since the flow field simulation model is based on equivalent reaction source terms, the steady-state analysis process can perceive the coupling effect of chemical reaction and gas-liquid mass transfer on the flow field, thereby achieving rapid and accurate acquisition of stable flow field data and providing a physically accurate stable flow field for subsequent transient calculations.

[0040] S5: Based on the reaction rate and the stable flow field data, determine the equivalent settling time of the resource recovery reaction, and based on the reaction rate and the equivalent settling time, correct the concentration of the reaction components.

[0041] The equivalent settling time described above represents the virtual reaction accumulation time implicit in the steady-state solution process. It can be understood as the equivalent time required for the reaction to continue at the reaction rate in real physical time to reach the mass transfer-reaction equilibrium state presented in the steady-state solution, providing a time basis for the concentration changes of the reduction reaction components. Since the above steady-state analysis process does not track the evolution of real physical time, while the chemical reaction continues during the flow field stabilization process, it is necessary to correct the concentration of the reaction components to ensure the physical consistency of the overall simulation. The equivalent settling time is derived by working backward from the reaction rate and stable flow field data. Based on the product relationship between the equivalent settling time and the reaction rate, the concentration correction amount of each reaction component is calculated to correct the concentration of the reaction components. While quickly obtaining stable flow field data through steady-state analysis, the concentration correction prevents the loss of accuracy due to ignoring the reaction concentration changes, thus providing reasonable initial chemical conditions for subsequent transient analysis.

[0042] It should be noted that after the above steady-state analysis process, the flow field simulation model needs to be frozen, that is, the flow field parameters (velocity, pressure, gas volume fraction, etc.) should be kept constant in subsequent processes. Since a relatively balanced steady-state flow field has been reached at this point, although the flow field will change slowly with the reaction in the subsequent actual reaction process, the time scale of this change is still measured in minutes or even hours. Compared with the extremely small time steps of mass transfer and reaction, the flow field change over a certain reaction time is negligible, thus avoiding the waste of computational resources.

[0043] S7: Based on the corrected concentration of the reaction components and the stable flow field data, perform transient analysis on the reaction simulation model until the resource recovery reaction ends, so as to obtain the numerical simulation results of the resource recovery reaction process.

[0044] In this embodiment, after the carbon dioxide resource recovery reaction process has reached a preliminary stable state, the dynamic evolution of the reaction and mass transfer is tracked through transient analysis. Specifically, a transient solver is used to solve the reaction simulation model in a time-progressive manner to update the concentrations of each reaction component and the dissolved carbon dioxide concentration in real time, simulating the real evolution of the reaction over time until the resource recovery reaction ends. For example, transient solving is continuously performed until the preset total reaction time (e.g., 2 hours) is reached, or the reaction reaches chemical equilibrium. Finally, the time-varying concentration data throughout the process is output as the numerical simulation result. Unlike steady-state analysis, transient analysis retains the time derivative term of the model and integrates it step by step over a certain time step to reflect the time-varying concentration distribution of each reaction component throughout the process, preserving the dynamic evolution information of the resource recovery reaction process as the numerical simulation result of the aforementioned resource recovery reaction process.

[0045] Based on the above ideas, the technical solution provided in this embodiment of the application performs alternating steady-state and transient solutions based on equivalent reaction source terms, combined with equivalent time compensation of physical reaction concentrations, thereby achieving efficient and accurate simulation of the carbon dioxide resource recovery reaction process. Specifically, the acquisition of the steady flow field is changed from relying on real physical time progression to direct steady-state solution, significantly reducing the computation time of this stage; through the equivalent time compensation mechanism, it is ensured that the component concentration distribution at the starting point of the transient calculation conforms to physical facts, avoiding the loss of reaction history; the transient solution after freezing the flow field can use a larger time step, further improving the simulation efficiency of long-cycle reaction processes, thereby achieving a significant reduction in computational cost and an improvement in simulation efficiency while ensuring simulation accuracy.

[0046] In one implementation, a three-dimensional geometric model is constructed based on an actual industrial reactor. A numerical simulation model of the carbon dioxide resource recovery reaction is then established based on the parameters of this three-dimensional geometric model. This three-dimensional geometric model is a spatial domain description constructed based on the actual physical structural parameters of the reactor (size, impeller configuration, inlet and outlet positions, etc.). Specifically:

[0047] A three-dimensional geometric model is established for the reactor of the resource recovery reaction, and a flow field simulation model is established based on the three-dimensional geometric model. The flow field simulation model includes at least a multiphase flow model, which is established based on a preset equivalent reaction source term.

[0048] Furthermore, a reaction simulation model is established based on a three-dimensional geometric model, wherein the reaction simulation model includes component transport equations and a first scalar transport equation, the first scalar transport equation being established based on a preset equivalent reaction source term.

[0049] In this embodiment, the multiphase flow model described above is a mathematical model describing the flow behavior of the gas-liquid two phases. An Euler-Euler framework is used to establish the governing equations for the gas and liquid phases, respectively, as the multiphase flow model. The multiphase flow model is established based on a pre-defined equivalent reaction source term, which influences the gas-liquid distribution to account for the impact of carbon dioxide dissolution and consumption on the gas phase volume fraction distribution, ensuring that the flow field obtained from the steady-state solution reflects the true equilibrium of mass transfer-reaction competition. Optionally, the multiphase flow model is established based on the scalar transport equation, which in turn is established based on the equivalent reaction source term.

[0050] The aforementioned component transport equations are partial differential equations describing the transport process of reaction components (reaction substrate and target product) in the liquid phase, used to reflect the concentration evolution of the reaction substrate and target product. The aforementioned first scalar transport equation is a custom scalar transport equation characterizing the dissolved concentration of carbon dioxide in the liquid phase, used to calculate the distribution of dissolved carbon dioxide concentration. Its source term consists of preset equivalent reaction source terms. As a gas-liquid mass transfer component, the concentration distribution of carbon dioxide is controlled by gas-liquid interface mass transfer. Unlike conventional component transport equations, the setting of the first scalar transport equation ensures that the concentration distribution can correctly reflect the coupling relationship between gas-liquid mass transfer and chemical reaction.

[0051] In one embodiment, the accuracy of the three-dimensional geometric model directly affects the reliability of the flow field simulation. Therefore, the three-dimensional geometric model can be divided into mesh regions to more accurately describe the geometric precision. In particular, for complex configurations such as stirred reactors, the geometric precision of the impeller region is especially critical. By dividing the three-dimensional geometric region into meshes and enhancing the geometric precision of specific meshes, a separate numerical simulation model can be built for each mesh. This allows for a more comprehensive and accurate acquisition of reaction process information and numerical simulation results for carbon dioxide resource recovery.

[0052] The technical solution provided in this embodiment refines the construction method and model system of the three-dimensional geometric model. Specifically, a corresponding three-dimensional geometric model is constructed based on the actual physical structural parameters of the industrial reactor, and a numerical simulation model of carbon dioxide resource recovery reaction coupled with the flow field and reaction process is established on this basis. Specifically, by reproducing the real structure of the reactor through the three-dimensional geometric model, and combining the multiphase flow model with the specific scalar transport equation, the coupled solution of gas-liquid two-phase flow, interphase mass transfer, and chemical reaction is achieved, which can accurately reflect the real equilibrium relationship between mass transfer and reaction. In addition, mesh optimization and partitioned modeling can significantly improve the reliability and accuracy of the simulation of flow field, component concentration, and reaction process under complex reactor configurations. Ultimately, it is possible to comprehensively and accurately obtain the reaction process information and numerical simulation results of the carbon dioxide resource recovery reaction, thereby comprehensively and accurately obtaining the relevant numerical simulation results and reaction process information of the carbon dioxide resource recovery reaction.

[0053] In one embodiment, the aforementioned flow field simulation model includes at least a multiphase flow model. This multiphase flow model includes a momentum equation and a continuity equation, used to solve for the velocity field distribution and volume fraction distribution of the gas and liquid phases, respectively. The multiphase flow model also includes a first scalar transport equation, used to solve for the dissolved carbon dioxide concentration. Based on this, and based on the concentrations of the reactants, a steady-state analysis is performed on the flow field simulation model to determine the stable flow field data for the resource recovery reaction. Specifically, this includes:

[0054] Based on the concentrations of the reactants, the momentum equation, continuity equation, and first scalar transport equation are analyzed to obtain steady-state flow field data. The concentrations of the reactants mentioned above are the baseline concentrations of each reactant in the resource recovery reaction, and the first scalar transport equation is established based on a pre-defined equivalent reaction source term. It should be noted that the first scalar transport equation of the multiphase flow model differs from that of the reaction simulation model in that the first scalar transport equation of the multiphase flow model does not have a time derivative term.

[0055] In this embodiment, the introduction of a first scalar transport equation into the multiphase flow model enables coupled equilibrium of mass transfer, reaction, and flow during the steady-state solution phase. Strong coupling exists between the momentum equation, continuity equation, and the first scalar transport equation: the velocity field affects the mass transfer coefficient, gas holdup affects the reaction interface area, and dissolved concentration affects the gas phase mass source term. Simultaneous analytical processing ensures that all three equations converge synchronously and coordinate during the iteration process, yielding a self-consistent equilibrium solution and overcoming the distortion caused by neglecting chemical reactions in traditional steady-state solutions.

[0056] In this embodiment, the concentration of reactant components is used as input to configure the liquid phase physical properties of the flow field simulation model, such as the relationship between density and viscosity and concentration, to perform steady-state analysis of the multiphase flow model. This steady-state analysis process can be understood as using a steady-state solver to iteratively solve the governing equations until the residuals converge, obtaining stable flow field data. For example, the steady-state solver is started, and the momentum equation, continuity equation, and first scalar transport equation are coupled and iterated. During the iteration process, the flow field distribution affects the gas-liquid mass transfer rate, and the combined effect of mass transfer and reaction affects the dissolved carbon dioxide concentration. The dissolved concentration is then fed back to the gas phase mass balance through the reaction consumption source term, forming a coupled solution of mass transfer, reaction, and flow. After iteration convergence, the velocity field, pressure field, gas phase volume fraction, and dissolved carbon dioxide concentration are extracted as stable flow field data.

[0057] The technical solution provided in this embodiment performs steady-state solutions on a flow field simulation model established based on equivalent reaction source terms to quickly and accurately obtain stable flow field data. Specifically, when determining the steady-state flow field, steady-state calculations based on equivalent reaction source terms replace lengthy and cumbersome transient calculations. Simultaneously, the dynamic balance between mass transfer input and reaction consumption is considered to determine more accurate steady-state flow field data. In particular, by embedding the first scalar transport equation in the steady-state solution stage, the coupling balance between mass transfer, reaction, and flow is achieved, overcoming the flow field distortion caused by neglecting chemical reactions in traditional steady-state solutions. Simultaneous analytical problems ensure synchronous convergence and mutual coordination between the equations, ultimately obtaining stable flow field data that reflects the coupling characteristics of mass transfer and reaction, providing reliable physical background conditions for subsequent transient calculations.

[0058] In one embodiment, the aforementioned equivalent reaction source term includes a gas-liquid mass transfer source term and a reaction consumption source term. The gas-liquid mass transfer source term can be understood as a mathematical expression describing the gas-liquid two-phase mass transfer rate, primarily calculated based on local flow field conditions (such as gas holdup, slip velocity, and interfacial area concentration). The reaction consumption source term calculates the chemical conversion rate based on the current reaction rate. Together, they determine the trend of carbon dioxide dissolved concentration change. Wherein:

[0059] The aforementioned gas-liquid mass transfer source terms are determined based on fluid dynamics conditions. These gas-liquid mass transfer source terms are used to characterize the coupling effect of gas-liquid mass transfer on carbon dioxide dissolution concentration. The aforementioned fluid dynamics conditions can be understood as multiphase flow field characteristic parameters that affect the gas-liquid mass transfer rate, which may include the saturated dissolution concentration of carbon dioxide, volumetric mass transfer coefficient, gas-liquid interphase contact area, liquid-side mass transfer coefficient, etc.

[0060] Furthermore, the aforementioned reaction consumption source term is determined based on reaction kinetic conditions, which characterize the coupling effect of the chemical reaction on the dissolved carbon dioxide concentration. These reaction kinetic conditions may include reaction rate, liquid phase density, relative molecular mass, etc. For example, the aforementioned reaction rate is determined based on chemical kinetics, such as an empirical model based on the concentration power law, or a mechanistic model that includes an adsorption step.

[0061] In this embodiment, changes in non-gas-liquid mass transfer components (i.e., reactant components) are not considered; instead, the mass source term of the gas-liquid mass transfer component (i.e., carbon dioxide) in the liquid phase is considered. The gas-liquid mass transfer source term is positive, representing gas dissolution, while the reaction consumption source term is negative, representing chemical reaction consumption. These reaction consumption source terms are set based on the maximum theoretical reaction rate at the reactant component concentration. Therefore, the steady-state solver can take into account the influence of chemical reactions on gas dissolution when calculating the flow field, thereby obtaining a stable flow field that matches the current reaction state.

[0062] In one embodiment, the above-mentioned reaction consumption source term is represented as follows: The above gas-liquid mass transfer source terms are represented as follows: ,in, The density of the liquid phase is... This represents the relative molecular mass of carbon dioxide. For the reaction rate, The mass transfer coefficient on the liquid side is denoted as . This represents the contact area between the gas and liquid phases. This represents the saturated solubility concentration of carbon dioxide. This represents the concentration of carbon dioxide dissolved in styrene oxide.

[0063] In one embodiment, the first scalar transport equation of the multiphase flow model is expressed in the following form: ,in, It represents the liquid volume fraction; The density of the liquid phase is... For liquid phase velocity, This represents the dissolved concentration of carbon dioxide. Where is the diffusion coefficient. For the source term consumed by the reaction, This is a gas-liquid mass transfer source term.

[0064] In one embodiment, the first scalar transport equation of the reaction simulation model is expressed in the following form: ,in, It represents the liquid volume fraction; The density of the liquid phase is... For liquid phase velocity, This refers to the concentration of dissolved carbon dioxide. Where is the diffusion coefficient. For the source term consumed by the reaction, This is a gas-liquid mass transfer source term.

[0065] The technical solution provided in this embodiment refines the composition and influencing conditions of the equivalent reaction source term. Specifically, the gas-liquid mass transfer source term calculates the mass transfer rate based on local flow field conditions, and the reaction consumption source term calculates the chemical conversion rate based on reaction kinetic conditions. Both, as positive and negative source terms respectively, jointly determine the net change trend of carbon dioxide dissolved concentration, and based on this, the first scalar transport equation of the multiphase flow model and the reaction simulation model are established. Through the balance mechanism between the gas-liquid mass transfer source term and the reaction consumption source term, the mass transfer-reaction coupling effect is accurately characterized at the source term level of the scalar transport equation, making the carbon dioxide dissolved concentration distribution obtained from the steady-state solution more realistic and accurate. Thus, without relying on long-term transient calculations, a stable flow field containing mass transfer and reaction characteristics can be quickly determined, enabling efficient and accurate numerical simulation of the carbon dioxide resource recovery process.

[0066] In one embodiment, the aforementioned stable flow field data includes flow field parameters and dissolved carbon dioxide concentration; determining the equivalent settling time of the resource recovery reaction based on the reaction rate and stable flow field data includes:

[0067] Based on the flow field parameters and carbon dioxide dissolved concentration, the current survival time increment is determined, and the current survival time reduction is preset based on the reaction rate. Furthermore, based on the survival time increment, survival time reduction, and flow field parameters, the equivalent settling time of the resource recovery reaction is determined.

[0068] The aforementioned survival time can be understood as the equivalent average time for mass transfer and reaction of fluid particles, i.e., the equivalent settling time. The aforementioned survival time increment characterizes the increment of survival time due to the gas-liquid mass transfer process, while the aforementioned survival time reduction characterizes the reduction of survival time due to the chemical reaction process. Since the aforementioned reaction rate can be predetermined based on chemical kinetics, the aforementioned survival time reduction can be directly obtained through the quantitative relationship between chemical kinetics and equivalent time. Optionally, the aforementioned flow field parameters include reaction rate, liquid phase volume fraction, liquid phase density, equivalent settling time, liquid phase velocity, diffusion coefficient, etc.

[0069] In one embodiment, the determination of the equivalent settling time can be characterized by a second scalar transport equation. This second scalar transport equation is expressed as follows: ,in, It is the liquid volume fraction. The density of the liquid phase is... For the equivalent stationary time, For liquid phase velocity, Where is the diffusion coefficient. For the increase in survival time, Reduce the amount to extend survival time.

[0070] In one embodiment, the above-mentioned survival time increment can be expressed as: The aforementioned reduction in survival time can be expressed as: ,in, This is the first custom scalar (i.e., carbon dioxide dissolved concentration). For the reaction rate, It is the liquid volume fraction. The density of the liquid phase is... This represents the survival time of fluid micro-particles.

[0071] The technical solution provided in this embodiment considers the influence of gas-liquid mass transfer and chemical reaction on fluid microparticles, thereby determining a more accurate steady-state flow field time. Specifically, the survival time increment characterizing the contribution of gas-liquid mass transfer is calculated by using flow field parameters and carbon dioxide dissolved concentration, and the survival time reduction characterizing the contribution of chemical reaction consumption is obtained based on the reaction rate determined by chemical kinetics. This allows for the construction of a corresponding second scalar transport equation to achieve a quantitative solution for the equivalent steady-state time. This realizes a quantitative characterization of the effect of gas-liquid mass transfer and chemical reaction on the fluid microparticle's time, enabling accurate and quantitative solution of the equivalent steady-state time in the carbon dioxide resource recovery process. Consequently, it can accurately and realistically reproduce the component concentration distribution, improving the accuracy and completeness of reaction process simulation and analysis.

[0072] In one embodiment, the concentration of the reaction component is the concentration of each reaction component in the resource recovery reaction, and the reaction components include the reaction substrate and the target product; the correction of the reaction component concentration based on the reaction rate and the equivalent settling time includes:

[0073] Obtain the first stoichiometric coefficient of the reaction substrate and the second stoichiometric coefficient of the target product. The first and second stoichiometric coefficients are used to reflect the stoichiometric ratio of the conversion of the reaction substrate and the target product, respectively. For example, in the reaction of carbon dioxide and styrene oxide to synthesize styrene carbonate, the first stoichiometric coefficient of the reaction substrate styrene oxide is -1 and the second stoichiometric coefficient of the target product styrene carbonate is +1, which characterizes the 1:1 molar conversion relationship.

[0074] Furthermore, based on the first stoichiometric coefficient, reaction rate, and equivalent stabilization time, a first concentration correction amount for the reaction substrate is determined. The mathematical relationship can be described as follows: the first concentration correction amount is the product of the first stoichiometric coefficient, reaction rate, and equivalent stabilization time. The concentration field of the reaction substrate is corrected based on the first concentration correction amount. Additionally, based on the second stoichiometric coefficient, reaction rate, and equivalent stabilization time, a second concentration correction amount for the target product is determined. The mathematical relationship can be described as follows: the second concentration correction amount is the product of the second stoichiometric coefficient, reaction rate, and equivalent stabilization time. The concentration field of the target product is corrected based on the second concentration correction amount.

[0075] In one embodiment, the concentration correction amount for each reaction component is determined as follows: ,in, is the stoichiometric coefficient of component i (-1 for the reaction substrate styrene oxide; 1 for the target product styrene carbonate). This represents the correction amount for the corresponding reaction component. This is the equivalent settling time. The above concentration correction amount... The corrected concentration fields of each component are obtained by superimposing them onto the initial component concentration field in the corresponding reaction simulation model. This corrected concentration field accurately reflects the chemical component distribution that should exist at the moment the steady-state flow field is established, providing an initial state that conforms to physical facts for subsequent transient calculations.

[0076] The technical solution provided in this embodiment refines the correction methods for the concentrations of each reaction component, including the concentrations of the reaction substrate and the target product. Specifically, the concentration correction amounts for the reaction substrate and the target product are determined by multiplying the stoichiometric coefficient, the reaction rate, and the equivalent settling time, respectively. These correction amounts are then superimposed on the initial component concentration field of the reaction simulation model to obtain the corrected concentration fields for each component. This ensures that the corrected concentration fields accurately reflect the true and reasonable chemical component distribution at the moment the steady-state flow field is established, providing an initial state that closely matches physical reality for subsequent transient calculations. This effectively improves the accuracy and reliability of the reaction component concentration field simulation and transient process calculations.

[0077] In one implementation, transient analysis of the reaction simulation model based on corrected reaction component concentrations and steady-state flow field data includes the following steps:

[0078] S71: Using the corrected reaction component concentrations and stable flow field data as reaction conditions, the reaction simulation model is iteratively analyzed;

[0079] The iterative analysis described above can be understood as using a transient solver to progressively advance the reaction status of the reaction simulation model in discrete time steps. That is, the reaction time in each iteration is one time step, and the reaction simulation model is solved once per time step, with the concentrations of reactant components updated based on the solution results, until the termination condition of the iterative analysis is reached. The termination condition of the iterative analysis is that the reaction reaches the preset reaction time.

[0080] S73: In any iteration of the iterative analysis, determine the transient reaction component concentration of the reaction simulation model in the current iteration, and judge whether the reaction simulation model meets the flow field update condition based on the transient reaction component concentration;

[0081] The aforementioned transient reaction component concentrations are the concentration distributions of the reaction substrate and target product obtained at a specific time step (a specific iteration), characterizing the chemical reaction state at that moment. When the flow field parameters at that moment match the current reaction state, it is considered that the current flow field change is small and does not meet the flow field update condition. The usual method of judgment is whether the change range of the transient reaction component concentration (e.g., the change range of the target product concentration) is higher than a preset threshold. If it is lower than the preset threshold, the flow field update condition is not met; otherwise, it is determined that the flow field update condition is met.

[0082] S75: If the reaction simulation model does not meet the flow field update conditions, the transient reaction component concentration is used as the numerical simulation result of the current iteration, and the transient reaction component concentration and the stable flow field data are used as the reaction conditions for the next iteration to drive the solution of the reaction simulation model in the next iteration.

[0083] In this embodiment, when the reaction simulation model is determined to meet the flow field update conditions, the following procedure is followed: Iterative analysis is paused, i.e., the time progression of the transient solver is paused. The transient reaction rate at the current moment is determined based on the transient reaction component concentration. Based on the transient reaction component concentration and the transient reaction rate, the stable flow field data is updated to obtain updated flow field data. This can be understood as follows: based on the transient reaction component concentration and the transient reaction rate, the flow field simulation model is re-analyzed to obtain updated stable flow field data. The transient reaction component concentration is used as the numerical simulation result of the current iteration, and iterative analysis continues using the transient reaction component concentration and the updated flow field data as reaction conditions.

[0084] In this embodiment, when re-performing steady-state analysis of the flow field simulation model, since the flow field simulation model can be established based on equivalent reaction source terms, which are set based on carbon dioxide dissolved concentration and reaction rate, it is necessary to obtain the current carbon dioxide dissolved concentration and reaction rate, and update the equivalent reaction source terms accordingly. The flow field simulation model is then updated based on the updated equivalent reaction source terms, and steady-state analysis is performed on the updated flow field simulation model. Similarly, the reaction simulation model is also established based on equivalent reaction source terms; therefore, it is also necessary to update the reaction simulation model based on the updated equivalent reaction source terms, and then perform transient solutions for subsequent iterations based on the updated reaction simulation model.

[0085] In this embodiment, after acquiring the updated flow field data, it is no longer necessary to update the concentration fields of each component. Before triggering the flow field update, the initial steady-state solution process has already performed equivalent time and concentration compensation through the steady flow field time, and the iterative analysis has advanced the actual physical time using a transient solver. The concentration of the reacting component at each time step is derived from the concentration field evolution of the previous step, completely recording the chemical reaction process from the starting point to the current moment. Therefore, the transient reacting component concentration itself is the result of real-time accumulation, rather than a frozen initial state, and no further concentration correction is required.

[0086] The technical solution provided in this embodiment starts the transient solver iteratively and analytically with the corrected reaction component concentrations and stable flow field data as the initial reaction conditions to determine the final numerical simulation results. Specifically, in each iteration, the reaction simulation model is solved to obtain the transient reaction component concentrations, and the flow field update is determined based on the magnitude of the concentration change. If the flow field update conditions are met, the steady-state calculation is performed again to determine the updated stable flow field data, and the transient calculation process continues. Therefore, by freezing the flow field, the transient calculation can focus on the reaction evolution with a larger time step, significantly improving the computational efficiency of long-term reaction processes. At the same time, by determining the flow field update conditions in real time, the systematic deviations caused by fixed freezing are avoided, ensuring that the time-varying concentration data throughout the process is accurate and reliable. An adaptive balance between efficiency and accuracy is achieved, thereby completing an efficient and accurate numerical simulation of the carbon dioxide resource recovery reaction process and improving the simulation accuracy and efficiency of numerical simulation processes for carbon dioxide resource recovery.

[0087] Please refer to Figure 2 This application provides an example of a reaction scenario for carbon dioxide resource recovery, in which carbon dioxide and styrene oxide are used as reactants to synthesize styrene carbonate. In a carbon dioxide resource recovery reactor (such as a bubble column), achieving flow field stability is a complex process of dynamic adjustment until equilibrium is reached. Specifically, the numerical simulation method for the above-mentioned carbon dioxide resource recovery is described in detail in the following steps.

[0088] S100: Establishing a numerical simulation model:

[0089] Among them, the numerical simulation model is used to numerically simulate the target reaction process for synthesizing the target product, including the flow field simulation model and the reaction simulation model;

[0090] S200: Steady-state flow field calculation:

[0091] The steady-state solution of the flow field simulation model is performed, in which the chemical reaction effect in the flow field simulation model is characterized by a pre-defined equivalent reaction source term to obtain stable flow field data that matches the current concentration of the reacting components.

[0092] S300: Component concentration field correction:

[0093] During or after the first execution of the steady-state flow field calculation step, the equivalent settling time is calculated based on the steady-state flow field data. Based on the equivalent settling time and the current reaction rate, the concentration correction of each reaction component during the establishment of the steady flow field due to the continuous chemical reaction is calculated. The concentration correction is added to the corresponding reaction component concentration, and the concentration field of each component in the reaction simulation model is updated.

[0094] S400: Transient reaction process calculation:

[0095] Based on stable flow field data and updated concentration fields of each component, the flow field is frozen, and a transient solver is used with a set reaction time step to solve the reaction simulation model in order to simulate the evolution of the reaction over time and continuously update the concentrations of each reaction component.

[0096] S500: Flow field-response alternating update:

[0097] During the execution of the transient reaction process calculation step, the concentration of at least one key reaction component is monitored. When the change in the concentration of the key reaction component reaches the preset update threshold, the transient solution is paused, and the concentration of each reaction component at the current moment is taken as the new current reaction component concentration. The steady-state flow field calculation step is then re-executed to update the steady-state flow field data. Subsequently, the transient reaction process calculation step is resumed and continues to be executed based on the new steady-state flow field data. Otherwise, the transient reaction process calculation step continues to be executed until the simulated reaction process ends. When the steady-state flow field calculation step is executed for the first time, the current reaction component concentration is taken as the initial unreacted concentration of the non-gas-liquid mass transfer component of the target reaction process.

[0098] In this embodiment, the numerical simulation model is set up based on the computational domain discretized from the physical structure of the reactor for the target reaction process. Specifically, a three-dimensional geometric model needs to be established according to the actual reactor size parameters, and meshing is performed on the geometric model. For example, a hexahedral-dominated unstructured mesh can be used to discretize the computational domain to ensure sufficient resolution for complex flow regions. For the reaction process of carbon dioxide and styrene oxide to synthesize styrene carbonate, it occurs in a stirred reactor, so a three-dimensional geometric model is established according to the physical structure parameters of the stirred reactor. As shown in Figure 3(a), the stirred reactor in this embodiment adopts a concentric dual-shaft stirring structure. The inner impeller is a single-layer six-bladed disk turbine impeller, and the outer impeller is a frame impeller. An annular gas distributor is set below the inner impeller. The stirred reactor is modeled in three dimensions to obtain the stirred reactor model. The stirred reactor model is discretized using a hexahedral-dominated unstructured mesh to obtain the meshing result shown in Figure 3(b). It should be noted that in the meshing result, the area near the stirring impeller in the stirred reactor needs to be locally meshed to improve the simulation accuracy of the corresponding area. For example, in the mesh generation result, the orthogonality quality of the mesh generation is higher than 0.3, the skewness is lower than 0.7, and the number of meshes meets the mesh independence requirement.

[0099] In this embodiment, the flow field simulation model includes a multiphase flow model, a turbulence model, and a group equilibrium model. To represent closed turbulence effects, a turbulence model is used, such as the standard k-ε turbulence model. The group equilibrium model can employ the Luo breaking up model or the Luo coalescing model. Specifically, the multiphase flow model is configured as follows:

[0100] The gas-liquid two-phase flow is described by the Euler-Euler multiphase flow model, and its governing equations are the momentum equation and continuity equation mentioned in the claims.

[0101] The liquid phase continuity equation is expressed as follows: The liquid phase momentum equation is expressed as: ,in, Liquid content, The density of the liquid phase is... The liquid phase flow rate is... For liquid phase mass transfer source items, in this embodiment, we take... , For pressure, For the viscous stress tensor of the liquid phase, It is the acceleration due to gravity. It is the interphase force between the liquid and gas phases. As the momentum source term, in this embodiment, we take... .

[0102] The gas-phase continuity equation is expressed as follows: The gas phase momentum equation is expressed as ,in, For gas holdup, For gas phase density, For gas phase flow rate, For gas-phase mass transfer source terms, in this embodiment, we take... ,in The density of the liquid phase is... This represents the saturated solubility concentration of carbon dioxide in styrene oxide. The volumetric mass transfer coefficient is . The solubility concentration of carbon dioxide in styrene oxide (here) That is, the first custom scalar that follows. ), For gas phase viscous stress tensor, It is the interphase force between the gas phase and the slurry phase. For gas phase mass-momentum source term, .

[0103] In this embodiment, the reaction simulation model includes component transport equations and a first scalar transport equation, which are constructed in the following manner:

[0104] Component transport equation: A component transport equation is set for the reactant styrene oxidation and the product styrene carbonate. The source term of the component transport equation is set as the product of the reaction rate and the relative molecular mass of each component.

[0105] The first scalar transport equation describes the concentration of dissolved carbon dioxide in styrene oxide. The general transient form of this equation is as follows: ,in, It is the liquid volume fraction. The density of the liquid phase is... This represents the solubility concentration of carbon dioxide in styrene oxide. For liquid phase velocity, Where is the diffusion coefficient. For chemical reaction source terms, This is a gas-liquid mass transfer source term.

[0106] In this embodiment, in step S200 above: firstly, boundary conditions are set, including: setting the gas inlet of the gas distributor in the stirred reactor as the velocity inlet and the gas outlet as the exhaust surface; and processing the rotation of the stirring paddle in the stirred reactor using a multiple reference system method. For example, the gas velocity inlet flow rate can be set to 11 m / s, the rotational speed of the paddle in the stirred reactor's inner region can be set to 360 rpm, and the rotational speed of the outer region can be set to 10 rpm, with the inner and outer paddles rotating in the same direction. Then, the velocities and volume fractions of each phase are initialized, and the initial concentration of the current reaction component is set. For the reaction of carbon dioxide and styrene oxide to synthesize styrene carbonate ester described in this embodiment, when this step is executed for the first time, the mass fraction of styrene oxide in the liquid phase is set to 100% (i.e., unreacted state), and the mass fraction of styrene carbonate ester is set to 0%. Subsequently, a preset equivalent reaction source term is activated. As mentioned above, for carbon dioxide as the target gas, its mass source term in the liquid phase is composed of a gas-liquid mass transfer source term and a chemical reaction consumption source term. The chemical reaction consumption source term is set based on the maximum theoretical consumption rate calculated according to the reaction kinetic equation, using the current concentration of the reacting components (i.e., a pure styrene oxide environment). By introducing this source term, the flow field solver can reflect the impact of gas dissolution caused by chemical reactions and gas-liquid mass transfer on the local gas holdup when calculating the gas-liquid two-phase distribution.

[0107] After completing the above settings, a steady-state solver is used to solve the configured flow field simulation model. For example, during the solution process, a coupled solver based on a pseudo-transient method is used. The pressure term is discretized using PRESTO! (pressure discretization scheme), the momentum equation and volume fraction term are discretized using a first-order upwind scheme, and the turbulence equation, each component, and the custom scalar transport equation are all discretized using a second-order upwind scheme. The convergence criteria are set as follows: the residual curves of each physical quantity decrease to below 0.001, the inlet and outlet flow rates are conserved, and the gas holdup and custom scalar monitoring values ​​in the reactor tend to stabilize. In this embodiment, the numerical calculation is performed using a high-performance CPU computing cluster, specifically a 96-core AMD EPYC 9654 processor with a base operating frequency of 2.40 GHz. The steady-state flow field calculation steps reached the convergence condition after 6320 iterations, and the solution time on the high-performance CPU computing cluster was approximately 9 hours. (Refer to...) Figure 4 As shown, when the steady-state flow field calculation steps reach the convergence condition, the distribution cloud map of carbon dioxide dissolved concentration in the flow field is obtained. Different colors in the figure represent the magnitude of carbon dioxide dissolved concentration.

[0108] In this embodiment, in step S300 above: after obtaining the first stable flow field data, in order to eliminate the loss of reaction process caused by the passage of "virtual time" during the steady-state calculation, a component concentration field correction is performed. Specifically, based on the stable flow field data, the transport equation for the second custom scalar as described above is solved: ,in, It is the liquid volume fraction. The density of the liquid phase is... For the survival time of fluid micro-elements, For liquid phase velocity, Where is the diffusion coefficient. This is the increase in survival time due to gas-liquid mass transfer. This is to reduce the survival time caused by chemical reactions.

[0109] By solving this equation, the equivalent settling time of each grid node within the computational domain can be obtained. Spatial distribution, such as Figure 5 As shown in the figure, different colors represent the equivalent settling time. In this embodiment, due to sufficient flow mixing, the... The distribution is relatively uniform. To obtain a single, well-defined equivalent settling time characterizing the entire flow field establishment phase, this step will calculate the time within the computational domain. Volume-weighted average The final equivalent settling time was determined. Subsequently, the reaction rate function r and the equivalent settling time were combined in this embodiment. Calculate the concentration correction of each reactant component during the initial establishment of a stable flow field due to the ongoing chemical reaction. .

[0110] Through the above calculations, the correction amounts for styrene oxide consumption and styrene carbonate formation were obtained. Finally, these concentration correction amounts were... These are then superimposed onto the initial component concentration fields in the corresponding reaction simulation models to obtain the corrected component concentration fields. These corrected concentration fields accurately reflect the chemical component distribution that should exist at the moment the flow field is established, providing a physically accurate initial state for subsequent transient calculations.

[0111] In this embodiment, in step S400 above: using the corrected component concentration field obtained in step S300 and the stable flow field data obtained in step S200 as initial conditions, the transient reaction simulation stage is entered. In this step, a "freeze flow field" strategy is adopted. Specifically, in the solver settings, the solution update for the flow field simulation model (i.e., the continuity equation, momentum equation, and turbulence equation) is turned off, keeping the flow field data unchanged; only the solution update for the reaction simulation model (i.e., the component transport equation and the first custom scalar transport equation) is enabled. The time step of the transient reaction is set to... (e.g., 0.1s) The transient solver is activated to simulate the evolution of the reaction over time. Within each time step, the solver calculates the consumption of styrene oxide, the formation of styrene carbonate, and the transfer and consumption of dissolved carbon dioxide based on locked convection and diffusion coefficients, thereby continuously updating the concentration fields of each component within the reactor.

[0112] In this embodiment, during step S500, the average mass fraction of the key reaction component (target product styrene carbonate) in the liquid phase is monitored in real time during the transient reaction process calculation step. For example, when the cumulative increase in the mass fraction of styrene carbonate since the last flow field calculation reaches a preset value (10.0%), the flow field update mechanism is triggered. Once this threshold is reached, the following operations are performed:

[0113] Pause transient solution: Stop time progression in step S400;

[0114] Update baseline concentration: Extract the concentration distribution data of each component in the calculation domain at the current moment and define it as the new "current reaction component concentration";

[0115] Recalculate the steady-state flow field: Return to step S200. At this point, based on the new concentrations of the reactants (i.e., the mixture containing a certain amount of products), recalculate the density, viscosity, and other physical properties of the mixture; simultaneously, update the reaction rate parameters in the equivalent reaction source term based on the new substrate concentration. Based on this, rerun the steady-state solver to obtain new steady-state flow field data adapted to the current chemical environment.

[0116] Resume transient calculation: After obtaining new stable flow field data, execute step S400 again, that is, freeze the new flow field and continue the transient component transport calculation at the current reaction time point.

[0117] This process of "transient reaction - monitoring and judgment - steady-state flow field update" is repeated until the simulation time reaches the preset total reaction time of 2 hours, thereby completing a high-precision numerical simulation of the entire synthesis process of the target product. For example, a curve showing the change in the mass fraction of styrene carbonate as a product throughout the reaction is determined and used as the numerical simulation result.

[0118] The above description is merely a scenario example provided in the specification and is not intended to limit the present invention. Any modifications, equivalent substitutions, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0119] Please see Figure 6 This application also provides a numerical simulation apparatus for carbon dioxide resource recovery reactions, the apparatus comprising:

[0120] The model building unit 100 is used to build a numerical simulation model of carbon dioxide resource recovery reaction, wherein the numerical simulation model includes a flow field simulation model and a reaction simulation model, and the numerical simulation model is determined based on a preset equivalent reaction source term.

[0121] The steady-state determination unit 200 is used to acquire the concentration of the reaction components and the reaction rate, and to perform steady-state analysis on the flow field simulation model based on the concentration of the reaction components to determine the steady-state flow field data of the resource recovery reaction.

[0122] The concentration correction unit 300 is used to determine the equivalent settling time of the resource recovery reaction based on the reaction rate and the stable flow field data, and to correct the concentration of the reaction component based on the reaction rate and the equivalent settling time.

[0123] The transient analysis unit 400 is used to perform transient analysis on the reaction simulation model based on the corrected reaction component concentration and the stable flow field data until the resource recovery reaction ends, so as to obtain the numerical simulation results of the resource recovery reaction process.

[0124] in,

[0125] In one embodiment, the model building unit 100 is specifically used to build a three-dimensional geometric model of the reactor for resource recovery reaction, and to build a flow field simulation model based on the three-dimensional geometric model. The flow field simulation model includes at least a multiphase flow model, which is built based on a preset equivalent reaction source term. The model also includes a reaction simulation model based on the three-dimensional geometric model, which includes a component transport equation and a first scalar transport equation, which is built based on a preset equivalent reaction source term.

[0126] In one embodiment, the steady-state determination unit 200 is specifically used to acquire the concentration of the reaction components and the reaction rate, and to analyze the momentum equation, continuity equation and first scalar transport equation based on the concentration of the reaction components to obtain stable flow field data. The concentration of the reaction components is the reference concentration of each reaction component in the resource recovery reaction, and the first scalar transport equation is established based on a preset equivalent reaction source term.

[0127] In one embodiment, the concentration correction unit 300 is specifically used to determine the current survival time increment based on flow field parameters and carbon dioxide dissolved concentration, and to preset the current survival time reduction based on the reaction rate. Based on the survival time increment, survival time reduction, and flow field parameters, it determines the equivalent settling time of the resource recovery reaction, obtains a first stoichiometric coefficient of the reaction substrate and a second stoichiometric coefficient of the target product, determines a first concentration correction amount of the reaction substrate based on the first stoichiometric coefficient, the reaction rate, and the equivalent settling time, corrects the concentration of the reaction substrate based on the first concentration correction amount, determines a second concentration correction amount of the target product based on the second stoichiometric coefficient, the reaction rate, and the equivalent settling time, and corrects the concentration of the target product based on the second concentration correction amount.

[0128] In one embodiment, the transient analysis unit 400 is specifically used to iteratively analyze the reaction simulation model using the modified reaction component concentration and stable flow field data as reaction conditions. In any iteration of the iterative analysis, the transient reaction component concentration of the reaction simulation model in the current iteration is determined. Based on the transient reaction component concentration, it is determined whether the reaction simulation model meets the flow field update conditions. If it is determined that the reaction simulation model does not meet the flow field update conditions, the transient reaction component concentration is used as the numerical simulation result of the current iteration, and the transient reaction component concentration and stable flow field data are used as the reaction conditions for the next iteration, until the resource recovery reaction ends, so as to obtain the numerical simulation result of the resource recovery reaction process.

[0129] Further functional descriptions of the above modules and units are the same as those in the corresponding embodiments described above, and will not be repeated here.

[0130] The numerical simulation device for carbon dioxide resource recovery in this application embodiment is presented in the form of a functional unit. Here, a unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that execute one or more software or fixed programs, or other devices that can provide the above functions.

[0131] Please see Figure 7 , Figure 7 This is a schematic diagram of the structure of a computer device provided in an embodiment of this application, such as... Figure 7As shown, the computer device includes one or more processors 10, memory 20, and interfaces for connecting the components, including high-speed interfaces and low-speed interfaces. The components communicate with each other via different buses and can be mounted on a common motherboard or otherwise installed as needed. The processors can process instructions executed within the computer device, including instructions stored in or on memory to display graphical information of a GUI on external input / output devices (such as display devices coupled to the interfaces). In some alternative implementations, multiple processors and / or multiple buses can be used with multiple memories and multiple memory modules, if desired. Similarly, multiple computer devices can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system). Figure 7 Take a processor 10 as an example.

[0132] Processor 10 may be a central processing unit, a network processor, or a combination thereof. Processor 10 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device may be a complex programmable logic device (CAMP), a field-programmable gate array (FPGA), a general-purpose array logic (GDA), or any combination thereof.

[0133] The memory 20 stores instructions executable by at least one processor 10 to cause the at least one processor 10 to perform the method shown in the above embodiments.

[0134] The memory 20 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the computer device. Furthermore, the memory 20 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, the memory 20 may optionally include memory remotely located relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0135] The memory 20 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory 20 may also include a combination of the above types of memory.

[0136] The computer device also includes a communication interface 30 for communicating with other devices or communication networks.

[0137] This application also provides a computer-readable storage medium. The methods described in this application can be implemented in hardware or firmware, or implemented as recordable on a storage medium, or implemented as computer code downloaded over a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and subsequently stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code. When the software or computer code is accessed and executed by the computer, processor, or hardware, the methods shown in the above embodiments are implemented.

[0138] The apparatus, module, or unit described in the above embodiments can be implemented by a computer chip or entity, or by a product having a certain function. A typical implementation device is a computer. Specifically, the computer can be, for example, a personal computer, laptop computer, cellular phone, camera phone, smartphone, personal digital assistant, media player, navigation device, email device, game console, tablet computer, wearable device, or any combination of these devices.

[0139] For ease of description, the above devices are described separately by function as various units. Of course, in implementing this application, the functions of each unit can be implemented in one or more software and / or hardware.

[0140] Those skilled in the art will understand that embodiments of this application can be provided as methods, apparatus, or computer devices. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0141] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus, and computer devices according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0142] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0143] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0144] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0145] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the device embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0146] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

[0147] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A numerical simulation method for carbon dioxide resource recovery reactions, characterized in that, The method includes: A numerical simulation model for carbon dioxide resource recovery reaction is established, wherein the numerical simulation model includes a flow field simulation model and a reaction simulation model, and the numerical simulation model is determined based on a preset equivalent reaction source term. The concentrations and rates of the reactants are obtained, and steady-state analysis is performed on the flow field simulation model based on the concentrations of the reactants to determine the steady-state flow field data of the resource recovery reaction. Based on the reaction rate and the stable flow field data, the equivalent settling time of the resource recovery reaction is determined, and the concentration of the reaction components is corrected based on the reaction rate and the equivalent settling time. Based on the corrected concentrations of the reaction components and the stable flow field data, the reaction simulation model is subjected to transient analysis until the resource recovery reaction ends, so as to obtain the numerical simulation results of the resource recovery reaction process. The stable flow field data includes flow field parameters and dissolved carbon dioxide concentration. Determining the equivalent settling time of the resource recovery reaction based on the reaction rate and the stable flow field data includes: determining the current survival time increment based on the flow field parameters and the dissolved carbon dioxide concentration, and pre-setting the current survival time decrement based on the reaction rate; and determining the equivalent settling time of the resource recovery reaction based on the survival time increment, the survival time decrement, and the flow field parameters. Wherein, the concentration of the reaction component refers to the concentration of each reaction component in the resource recovery reaction, and the reaction component includes a reaction substrate and a target product; the correction of the concentration of the reaction component based on the reaction rate and the equivalent stabilization time includes: obtaining a first stoichiometric coefficient of the reaction substrate and a second stoichiometric coefficient of the target product; determining a first concentration correction amount of the reaction substrate based on the first stoichiometric coefficient, the reaction rate, and the equivalent stabilization time, and correcting the concentration of the reaction substrate based on the first concentration correction amount; determining a second concentration correction amount of the target product based on the second stoichiometric coefficient, the reaction rate, and the equivalent stabilization time, and correcting the concentration of the target product based on the second concentration correction amount.

2. The method according to claim 1, characterized in that, The numerical simulation model for carbon dioxide resource recovery includes: A three-dimensional geometric model is established for the reactor of the resource recovery reaction, and a flow field simulation model is established based on the three-dimensional geometric model. The flow field simulation model includes at least a multiphase flow model, which is established based on a preset equivalent reaction source term. Furthermore, the reaction simulation model is established based on the three-dimensional geometric model, wherein the reaction simulation model includes a component transport equation and a first scalar transport equation, the first scalar transport equation being established based on a preset equivalent reaction source term.

3. The method according to claim 1, characterized in that, The flow field simulation model includes at least a multiphase flow model, which includes a momentum equation, a continuity equation, and a first scalar transport equation. Based on the concentration of the reactants, steady-state analysis is performed on the flow field simulation model to determine the steady-state flow field data of the resource recovery reaction, including: Based on the concentration of the reactants, the momentum equation, continuity equation, and first scalar transport equation are analyzed to obtain the steady flow field data. Wherein, the concentration of the reaction component is the reference concentration of each reaction component in the resource recovery reaction, and the first scalar transport equation is established based on a preset equivalent reaction source term.

4. The method according to any one of claims 1, 2, or 3, characterized in that, The equivalent reaction source term includes a gas-liquid mass transfer source term and a reaction consumption source term; wherein: The gas-liquid mass transfer source term is determined based on fluid dynamics conditions, and the gas-liquid mass transfer source term is used to characterize the coupling effect of gas-liquid mass transfer on carbon dioxide dissolved concentration. Furthermore, the reaction consumption source term is determined based on reaction kinetic conditions, and the reaction consumption source term is used to characterize the coupling effect of the chemical reaction on the carbon dioxide dissolved concentration.

5. The method according to claim 1, characterized in that, Based on the corrected reaction component concentrations and the stable flow field data, transient analysis of the reaction simulation model includes: The reaction simulation model is iteratively analyzed using the corrected concentrations of the reaction components and the stable flow field data as reaction conditions; In any iteration of the iterative analysis, the transient reaction component concentration of the reaction simulation model in the current iteration is determined, and the reaction simulation model is judged to meet the flow field update condition based on the transient reaction component concentration. If the reaction simulation model is determined not to meet the flow field update conditions, the transient reaction component concentration is used as the numerical simulation result of the current iteration, and the transient reaction component concentration and the stable flow field data are used as the reaction conditions for the next iteration.

6. The method according to claim 5, characterized in that, If the reaction simulation model is determined to satisfy the flow field update condition, the method further includes: Pause the iterative analysis and determine the transient reaction rate at the current moment based on the concentration of the transient reaction component; Based on the transient reaction component concentration and the transient reaction rate, the stable flow field data is updated to obtain updated flow field data; The transient reaction component concentration is used as the numerical simulation result of the current iteration, and the iterative analysis is continued using the transient reaction component concentration and the updated flow field data as reaction conditions.

7. A numerical simulation device for carbon dioxide resource recovery reactions, characterized in that, The device includes: The model building unit is used to build a numerical simulation model of carbon dioxide resource recovery reaction, wherein the numerical simulation model includes a flow field simulation model and a reaction simulation model, and the numerical simulation model is determined based on a preset equivalent reaction source term. A steady-state determination unit is used to acquire the concentration of the reaction components and the reaction rate, and to perform steady-state analysis on the flow field simulation model based on the concentration of the reaction components to determine the steady-state flow field data of the resource recovery reaction. A concentration correction unit is used to determine the equivalent settling time of the resource recovery reaction based on the reaction rate and the stable flow field data, and to correct the concentration of the reaction components based on the reaction rate and the equivalent settling time. The transient analysis unit is used to perform transient analysis on the reaction simulation model based on the corrected reaction component concentration and the stable flow field data until the resource recovery reaction ends, so as to obtain the numerical simulation results of the resource recovery reaction process. The stable flow field data includes flow field parameters and dissolved carbon dioxide concentration. Determining the equivalent settling time of the resource recovery reaction based on the reaction rate and the stable flow field data includes: determining the current survival time increment based on the flow field parameters and the dissolved carbon dioxide concentration, and pre-setting the current survival time decrement based on the reaction rate; and determining the equivalent settling time of the resource recovery reaction based on the survival time increment, the survival time decrement, and the flow field parameters. Wherein, the concentration of the reaction component refers to the concentration of each reaction component in the resource recovery reaction, and the reaction component includes a reaction substrate and a target product; the correction of the concentration of the reaction component based on the reaction rate and the equivalent stabilization time includes: obtaining a first stoichiometric coefficient of the reaction substrate and a second stoichiometric coefficient of the target product; determining a first concentration correction amount of the reaction substrate based on the first stoichiometric coefficient, the reaction rate, and the equivalent stabilization time, and correcting the concentration of the reaction substrate based on the first concentration correction amount; determining a second concentration correction amount of the target product based on the second stoichiometric coefficient, the reaction rate, and the equivalent stabilization time, and correcting the concentration of the target product based on the second concentration correction amount.

8. A computer device, characterized in that, include: A memory and a processor are interconnected, the memory storing computer instructions, and the processor executing the computer instructions to perform the numerical simulation method for carbon dioxide resource recovery reaction as described in any one of claims 1 to 6.

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