A modeling method and device of a diesel aromatic hydrocarbon simulated moving bed adsorption separation device

Abstract

The application discloses a modeling method and device for a diesel aromatic hydrocarbon simulated moving bed adsorption separation device, and the method comprises the following steps: based on material balance principle and mass transfer mechanism, a bed layer flowing phase dynamic mechanism model and a bed layer fixed phase dynamic mechanism model of different components are respectively constructed; based on finite element method and orthogonal configuration method, discretization processing is performed to obtain a bed layer flowing phase dynamic mechanism discrete model and a bed layer fixed phase dynamic mechanism discrete model; based on material balance principle, a node model of different components is respectively constructed; and then, a bed layer dynamic mechanism discrete model of different components and a full-component bed layer dynamic mechanism discrete model are constructed, so that model parameters are optimized based on the full-component bed layer dynamic mechanism discrete model. The method can comprehensively, systematically and accurately reveal the quantitative relationship between a large number of parameters of the diesel aromatic hydrocarbon simulated moving bed adsorption separation device and device performance indexes, thereby realizing optimized design and optimized operation of the device, and having important industrial application value.

Description

Technical Field

[0001] This invention relates to the field of simulated moving bed adsorption separation technology, and in particular to a modeling method and apparatus for a diesel aromatics simulated moving bed adsorption separation device. Background Technology

[0002] Aromatics in industrial diesel feedstock are difficult to burn completely, causing environmental pollution. The diesel aromatics simulated moving bed adsorption separation device can separate aromatics from industrial diesel feedstock and use them as high-value-added chemicals. At the same time, the remaining non-aromatics in the industrial diesel feedstock become clean diesel. This device achieves the two strategic goals of clean diesel production and obtaining high-value-added aromatic chemicals, and is an important milestone in the leapfrog development of the petrochemical industry.

[0003] Numerous bed parameters, operating parameters, kinetic parameters, adsorption isotherms, feed composition parameters, and desorbent composition parameters all affect the performance of a diesel aromatics simulated moving bed adsorption separation unit. By employing modeling methods, this study comprehensively, systematically, and accurately reveals the quantitative relationship between these parameters and the unit's performance indicators, thereby enabling the optimized design and operation of the diesel aromatics simulated moving bed adsorption separation unit. This has significant industrial application value. Summary of the Invention

[0004] To optimize the design and operation of a diesel aromatics simulated moving bed adsorption separation device, thereby enriching process routes and increasing selection options, this invention provides a modeling method and apparatus for a diesel aromatics simulated moving bed adsorption separation device.

[0005] In a first aspect, embodiments of the present invention provide a modeling method for a diesel aromatics simulated moving bed adsorption separation device. The diesel aromatics simulated moving bed adsorption device may include: several beds, adjacent beds being sequentially connected along the flow direction of the mobile phase; sample inlet nodes, extractor nodes, desorbent nodes, and residual liquid nodes are arranged between the beds, and the nodes synchronously move to the next bed according to a step time along the flow direction of the mobile phase, thereby realizing the simulated moving operation of the diesel aromatics simulated moving bed adsorption separation device on the beds; the modeling method may include:

[0006] Based on the principles of material balance and mass transfer mechanism, dynamic mechanism models of the fluid phase and the stationary phase of the bed are constructed for different components, namely aromatic components, non-aromatic components and desorbent components in the diesel fuel.

[0007] The dynamic mechanism model of the bed fluid phase is discretized based on the finite element method and the orthogonal collocation method to obtain discrete models of the dynamic mechanism of the bed fluid phase with different components.

[0008] The dynamic mechanism model of the bed stationary phase is discretized based on the orthogonal configuration method to obtain discrete models of the dynamic mechanism of the bed stationary phase with different components.

[0009] Based on the principle of material balance, node models for different components are constructed respectively; wherein, the node models include: injection node model, extract node model, desorbent node model and residual liquid node model;

[0010] Based on the discretized dynamic mechanism model of the fluid phase in the bed, the discretized dynamic mechanism model of the stationary phase in the bed, and the node model, discretized dynamic mechanism models of different components in the bed are constructed.

[0011] Based on the discrete model of the dynamic mechanism of the bed with different components, a discrete model of the dynamic mechanism of the whole component bed of the diesel aromatics simulated moving bed adsorption device is constructed, so as to optimize the model parameters of the diesel aromatics simulated moving bed adsorption device based on the discrete model of the dynamic mechanism of the whole component bed.

[0012] Optionally, the discretization of the bed flow phase dynamic mechanism model based on the finite element method and orthogonal collocation method to obtain discrete models of the bed flow phase dynamic mechanism with different components may include:

[0013] The dimensionless axial spatial coordinates of each bed corresponding to the dynamic mechanism model of the fluid phase in the bed are divided into NE finite elements;

[0014] The first-order discretization matrix and the second-order discretization matrix are derived using NP-order Legendre orthogonal polynomials defined in the interval [0,1].

[0015] Based on the first-order discretization matrix and the second-order discretization matrix, the dynamic mechanism model of the bed flow phase on each finite element is discretized to obtain the discretized model of the dynamic mechanism of the bed flow phase with different components.

[0016] Optionally, the discretization of the dynamic mechanism model of the bed stationary phase based on the orthogonal configuration method to obtain discrete models of the dynamic mechanism of the bed stationary phase with different components may include:

[0017] Based on ρ 2 The first-order discretization matrix and the second-order discretization matrix are derived from the (2×NPR) order Jacobian orthogonal polynomial.

[0018] Based on the first-order discretization matrix and the second-order discretization matrix, the dynamic mechanism model of the bed stationary phase is discretized to obtain discrete models of the dynamic mechanism of the bed stationary phase with different components.

[0019] Optionally, the adsorption amount of different components on the adsorbent in the dynamic mechanism model of the bed stationary phase is determined by multi-component nonlinear competitive adsorption isotherms.

[0020] Optionally, the multi-component nonlinear competitive adsorption isotherm is a modified multi-component Langmuir-type adsorption isotherm with selective adsorption dual centers;

[0021] Among them, the selective adsorption dual centers include: aromatic hydrocarbon selective adsorption centers and non-aromatic hydrocarbon selective adsorption centers.

[0022] Optionally, dynamic mechanism models of bed flow phases with different components can be constructed based on the axial dispersion coefficient and membrane mass transfer coefficient in the kinetic parameters of different components.

[0023] Optionally, dynamic mechanism models of the bed stationary phase with different components can be constructed based on the intraparticle diffusion coefficient in the kinetic parameters of different components.

[0024] Secondly, embodiments of the present invention provide a modeling apparatus for a diesel aromatics simulated moving bed adsorption separation device, which may include:

[0025] The bed dynamic mechanism model construction module is used to construct bed mobile phase dynamic mechanism models and bed stationary phase dynamic mechanism models based on the material balance principle and mass transfer mechanism, respectively, according to the aromatic components, non-aromatic components and desorbent components in the diesel.

[0026] The discretization module is used to discretize the dynamic mechanism model of the bed mobile phase based on the finite element method and the orthogonal configuration method to obtain discrete models of the dynamic mechanism of the bed mobile phase with different components; and to discretize the dynamic mechanism model of the bed stationary phase based on the orthogonal configuration method to obtain discrete models of the dynamic mechanism of the bed stationary phase with different components.

[0027] The node model construction module is used to construct node models for different components based on the principle of material balance; wherein, the node models include: injection node model, extract node model, desorbent node model and residual liquid node model;

[0028] The bed dynamic mechanism discrete model construction module is used to construct bed dynamic mechanism discrete models with different components based on the bed mobile phase dynamic mechanism discrete model, the bed stationary phase dynamic mechanism discrete model and the node model.

[0029] The module for constructing a discrete model of the dynamic mechanism of the whole-component bed is used to construct a discrete model of the dynamic mechanism of the whole-component bed of the diesel aromatics simulated moving bed adsorption device based on the discrete model of the dynamic mechanism of the bed of different components.

[0030] The optimization module is used to optimize the model parameters of the diesel aromatics simulated moving bed adsorption device based on the discrete model of the dynamic mechanism of the whole-component bed.

[0031] Thirdly, embodiments of the present invention provide a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the modeling method for a diesel aromatics simulated moving bed adsorption separation device as described in the first aspect.

[0032] Fourthly, embodiments of the present invention provide a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the modeling method for a diesel aromatics simulated moving bed adsorption separation device as described in the first aspect.

[0033] The beneficial effects of the above-described technical solutions provided in the embodiments of the present invention include at least the following:

[0034] This invention provides a modeling method and apparatus for a diesel aromatics simulated moving bed adsorption separation device. This method can comprehensively, systematically, and accurately reveal the quantitative relationships between numerous bed parameters, operating parameters, kinetic parameters, adsorption isotherms, feed composition parameters, desorbent composition parameters, and device performance indicators of the diesel aromatics simulated moving bed adsorption separation device. This enables the optimized design and operation of the diesel aromatics simulated moving bed adsorption separation device and has significant industrial application value.

[0035] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0036] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0037] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0038] Figure 1 This is a schematic diagram of the diesel aromatics simulated moving bed adsorption separation industrial device provided in the embodiments of the present invention;

[0039] Figure 2 This is a flowchart of the modeling method for the diesel aromatics simulated moving bed adsorption separation device provided in the embodiments of the present invention;

[0040] Figure 3This is a schematic diagram of the modeling device for the diesel aromatics simulated moving bed adsorption separation device provided in an embodiment of the present invention. Detailed Implementation

[0041] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0042] The diesel aromatics simulated moving bed adsorption separation device in this embodiment of the invention is used to separate aromatics and non-aromatics in diesel fuel. Since the operating parameters of the diesel aromatics simulated moving bed adsorption separation device directly affect the device's performance indicators, how to optimize the design and operation of the diesel aromatics simulated moving bed adsorption separation device is a technical problem that urgently needs to be solved by those skilled in the art. In view of the above technical problem, this embodiment of the invention provides a modeling method and device for a diesel aromatics simulated moving bed adsorption separation device.

[0043] This invention provides a modeling method for a diesel aromatics simulated moving bed adsorption separation device, referring to... Figure 1 As shown, the diesel aromatics simulated moving bed adsorption device may include: several beds, adjacent beds are connected sequentially along the flow direction of the bed mobile phase, and sample inlet nodes, extractor nodes, desorbent nodes and residual liquid nodes are arranged between the beds, and the nodes move synchronously to the next bed according to the step time along the flow direction of the bed mobile phase, so as to realize the simulated moving operation of the bed by the diesel aromatics simulated moving bed adsorption separation device.

[0044] The bed parameters of the diesel aromatics simulated moving bed adsorption device in the embodiments of the present invention may include the total number of beds, the number of beds in zone 1, zone 2, zone 3, and zone 4, the bed diameter, the bed height, the bed porosity, and the adsorbent radius; the operating parameters include the step time, the injection flow rate, the extract flow rate, the raffinate flow rate, the desorbent flow rate, the zone 1 flow rate, the zone 2 flow rate, the zone 3 flow rate, and the zone 4 flow rate; the kinetic parameters include the axial dispersion coefficient, the membrane mass transfer coefficient, and the intraparticle diffusion coefficient; the adsorption isotherm is a multi-component nonlinear competitive adsorption isotherm; the feed composition parameters include the concentration of complex aromatic components and the concentration of complex non-aromatic components in the diesel fuel; and the desorbent composition parameters include the concentration of strong desorbent and the concentration of weak desorbent.

[0045] The inventors have divided the complex aromatic components in diesel fuel into at least three aggregated components, which may include total monocyclic aromatics, total bicyclic aromatics, and total tricyclic aromatics; divided the complex non-aromatic components in diesel fuel into at least two aggregated components, which may include total alkanes and total cycloalkanes; and divided the desorbent components into at least two components, including a strong desorbent and a weak desorbent. The modeling method in this embodiment involves at least seven components, including total monocyclic aromatics, total bicyclic aromatics, total tricyclic aromatics, total alkanes, total cycloalkanes, a strong desorbent, and a weak desorbent. The sample injection includes both aromatic and non-aromatic components from the diesel fuel, entering the device through the sample injection node; the desorbent enters the device through the desorbent node; and the aromatic-rich extract is discharged through the extract node. The apparatus consists of a non-aromatic raffinate, which exits through the raffinate node. The total number of beds in the apparatus is between 4 and 48. The beds are connected along the flow direction of the mobile phase. The bed between the injection node and the raffinate node is defined as Zone 1, the bed between the extraction node and the injection node as Zone 2, the bed between the desorbent node and the extraction node as Zone 3, and the bed between the raffinate node and the desorbent node as Zone 4. The injection node, extraction node, desorbent node, and raffinate node move synchronously to the next bed along the flow direction of the mobile phase, according to a step time rhythm, thus simulating the movement of the beds.

[0046] Reference Figure 1 As shown, in this embodiment of the invention, the total number of bed layers is 12, configured in four zones as follows: 2 beds in zone 4, 3 beds in zone 3, 3 beds in zone 2, and 4 beds in zone 1. Therefore, the model established by the above modeling method in this embodiment includes 12 bed layer models, each including a mobile phase model and a stationary phase model. The volume of the mobile phase is the product of the bed volume and the bed porosity; the volume of the stationary phase is the volume of the adsorbent in the bed.

[0047] Reference Figure 2 As shown, the modeling method provided in this embodiment of the invention may include the following steps:

[0048] Step S21: Based on the material balance principle and mass transfer mechanism, construct dynamic mechanism models of the fluid phase and stationary phase of the bed, respectively, for different components in diesel fuel, including aromatic components, non-aromatic components and desorbent components.

[0049] The dynamic mechanism model of the bed flow phase constructed in this embodiment can be expressed by a set of partial differential equations as follows:

[0050]

[0051] Among them, c jc represents the concentration of the j-th component in the fluid phase of the bed. Pj Let be the liquid phase concentration of the j-th component in the adsorbent pores; t be time; L be the bed height; x be the dimensionless axial spatial coordinate of the bed; R be the liquid phase concentration of the j-th component in the adsorbent pores; L be the ... P ρ is the adsorbent radius; ρ is the dimensionless radial spatial coordinate of the adsorbent; ε is the bed porosity; u is the mobile phase void velocity, u=Q / (επd 2 / 4), where Q is the flow rate in the zone where the bed is located, and d is the diameter of the bed; D Lj k is the axial dispersion coefficient of the j-th component; Fj Let be the membrane mass transfer coefficient of the j-th component.

[0052] In this embodiment, the axial dispersion coefficient D of the j-th component is as follows. Lj The estimation formula is:

[0053] The membrane mass transfer coefficient k of the j-th component mentioned above Fj The estimation formula is:

[0054] Where Re is the Reynolds number, Re = 2R P ρu / μ;R P ρ is the adsorbent radius; u is the mobile phase density; ε is the mobile phase void velocity; and ε is the mobile phase viscosity.

[0055] The dynamic mechanism model of the bed stationary phase constructed in this embodiment can be represented by a system of partial differential equations as follows:

[0056]

[0057] Where, q j The adsorption amount of the j-th component on the adsorbent is calculated using a multi-component nonlinear competitive adsorption isotherm; D Pj Let be the intraparticle diffusion coefficient of the j-th component.

[0058] The intraparticle diffusion coefficient D of the j-th component mentioned above Pj The estimation formula is:

[0059] Where, ε P D represents the porosity of the adsorbent. Mj Let be the molecular diffusion coefficient of the j-th component.

[0060] Step S22: Discretize the dynamic mechanism model of the bed fluid phase based on the finite element method and the orthogonal configuration method to obtain discrete models of the dynamic mechanism of the bed fluid phase with different components.

[0061] In this step, the dimensionless axial spatial coordinates of each bed corresponding to the dynamic mechanism model of the bed fluid phase are first divided into NE finite elements. Then, the first-order discretization matrix and the second-order discretization matrix are derived using NP-order Legendre orthogonal polynomials with a defined interval of [0,1]. Finally, based on the first-order discretization matrix and the second-order discretization matrix, the dynamic mechanism model of the bed fluid phase on each finite element is discretized to obtain the discretized models of the dynamic mechanism of the bed fluid phase with different components.

[0062] In the specific implementation of this step, the dimensionless axial spatial coordinates of each bed layer are first divided into NE finite elements, which are 0 = X1 < X2 ... X NE <X NE+1 =1; then, the first-order discretization matrix A and the second-order discretization matrix B are derived from the NP-order Legendre orthogonal polynomials defined in the interval [0,1]; then, based on the above discretization matrices, the partial differential equations of the bed flow phase dynamic mechanism model on each finite element are discretized to obtain the discretized model of the bed flow phase dynamic mechanism of the j-th component; in this embodiment, the discretized model of the bed flow phase dynamic mechanism of the j-th component is a set of differential-algebraic mixed equations, as follows:

[0063]

[0064] Step S23: Discretize the dynamic mechanism model of the bed stationary phase based on the orthogonal configuration method to obtain discrete models of the dynamic mechanism of the bed stationary phase with different components.

[0065] This step is first based on ρ 2 The first-order and second-order discretization matrices are derived from the (2×NPR) order Jacobi orthogonal polynomials. Then, based on the first-order and second-order discretization matrices, the dynamic mechanism model of the bed fixed phase is discretized to obtain the discretized dynamic mechanism model of the bed fixed phase with different components.

[0066] In this step, the dynamic mechanism model of the bed stationary phase of the j-th component, constructed using the orthogonal configuration discretization method, is discretized; specifically as follows: A model based on ρ... 2 The first-order discretized matrix is ​​derived from the (2×NPR) order Jacobian orthogonal polynomial. With second-order discretization matrix The dynamic mechanism model of the bed stationary phase of the j-th component is discretized to obtain the discrete model of the dynamic mechanism of the bed stationary phase of the j-th component; the discrete model of the dynamic mechanism of the bed mobile phase of the j-th component is a set of differential-algebraic mixed equations, as follows:

[0067]

[0068] It should be noted that the execution of steps S22 and S23 is not in any particular order. Step S22 can be executed first and then step S23, or step S23 can be executed first and then step S22. Of course, steps S22 and S23 can also be executed simultaneously. This embodiment of the invention does not impose any specific limitations on this.

[0069] Step S24: Based on the principle of material balance, construct node models for different components; among which, the node models include: injection node model, extract node model, desorbent node model and residual liquid node model.

[0070] The set of algebraic equations for the injection node model in this embodiment is expressed as follows:

[0071]

[0072] The above-mentioned extractable fluid node model is a set of algebraic equations, represented as follows:

[0073]

[0074] The above desorbent nodal model is a set of algebraic equations, represented as follows:

[0075]

[0076] The above-mentioned residual liquid node model is a set of algebraic equations, represented as follows:

[0077]

[0078] Among them, Q F Q is the injection flow rate; E Q is the flow rate of the extracted fluid; R Q is the residual liquid flow rate; D Q is the desorbent flow rate; I For Zone 1 traffic; Q II For Zone 2 traffic; Q III For three zones of traffic; Q IV For the flow rate of the fourth zone; c j,F c is the concentration parameter of the j-th component in the feed composition parameters; j,D c is the concentration parameter of the j-th component in the desorbent composition parameters; j,E c is the concentration of the j-th component in the extract; j,R The concentration of the j-th component in the raffinate; Let J be the concentration of the j-th component at the entrance of zone 1 in the fluid phase of the bed. Let J be the concentration of the j-th component at the entrance of Zone 2 in the fluid phase of the bed. Let J be the concentration of the j-th component at the entrance of zone three in the fluid phase of the bed. Let J be the concentration of the j-th component at the entrance of zone four in the fluid phase of the bed. Let J be the concentration of the j-th component in the mobile phase of the bed at the outlet of Zone 1. The concentration of the j-th component in the mobile phase of the bed at the outlet of zone two; Let J be the concentration of the j-th component in the fluid phase of the bed at the outlet of zone three. The concentration of the j-th component at the outlet of zone four in the mobile phase of the bed.

[0079] It should also be noted that step S24 can be executed simultaneously with or before steps S21 and S22, as long as the node model is constructed before step S25. This embodiment of the invention does not impose any specific limitations on this.

[0080] Step S25: Based on the discrete models of the dynamic mechanism of the fluid phase, the dynamic mechanism of the stationary phase, and the nodal model, construct discrete models of the dynamic mechanism of the bed with different components. This step constructs discrete models of the dynamic mechanism of the bed with different components based on the discrete models of the dynamic mechanism of the fluid phase obtained in step S22, the discrete models of the dynamic mechanism of the stationary phase obtained in step S23, and the nodal models of the different components constructed in step S24.

[0081] Step S26: Based on the discrete models of bed dynamic mechanisms for different components, construct a discrete model of the full-component bed dynamic mechanism for the diesel aromatics simulated moving bed adsorption device. The discrete model of the full-component bed dynamic mechanism in this step involves each of the seven components mentioned above. The discrete models of the bed dynamic mechanism for each component are combined to construct the discrete model of the full-component bed dynamic mechanism.

[0082] Step S27: Optimize the model parameters of the diesel aromatics simulated moving bed adsorption device based on the discrete model of the dynamic mechanism of the whole component bed.

[0083] The discrete model of the dynamic mechanism of the whole-component bed layer constructed in this step is a large-scale differential-algebraic mixed equation system, which is solved using the Gill method.

[0084] The modeling method provided in this embodiment of the invention can comprehensively, systematically and accurately reveal the quantitative relationship between numerous bed parameters, operating parameters, kinetic parameters, adsorption isotherms, feed composition parameters, desorbent composition parameters and device performance indicators of the diesel aromatics simulated moving bed adsorption separation device, thereby realizing the optimized design and operation of the diesel aromatics simulated moving bed adsorption separation device, which has important industrial application value.

[0085] In an optional embodiment, the adsorption amount of different components on the adsorbent in the dynamic mechanism model of the bed stationary phase is determined by a multi-component nonlinear competitive adsorption isotherm.

[0086] In one specific embodiment, the multi-component nonlinear competitive adsorption isotherm is a modified multi-component Langmuir-type adsorption isotherm with selective adsorption dual centers; wherein, the selective adsorption dual centers include: an aromatic selective adsorption center and a non-aromatic selective adsorption center.

[0087] In this embodiment, the improved multi-component Langmuir-type adsorption isotherm with selective adsorption dual centers is as follows:

[0088]

[0089] Where, q j c represents the adsorption amount of the j-th component on the adsorbent. Pj Let q be the liquid phase concentration of the j-th component in the pores of the adsorbent; Mj K represents the saturated adsorption capacity of the j-th component at the aromatic selective adsorption center of the adsorbent; j Let be the adsorption constant of the j-th component at the aromatic selective adsorption center of the adsorbent; denoted as the saturated adsorption amount of the j-th component at the non-aromatic selective adsorption center of the adsorbent; Let be the adsorption constant of the j-th component at the non-aromatic selective adsorption center of the adsorbent.

[0090] In another optional embodiment, a dynamic mechanism model of the bed flow phase of different components is constructed based on the axial dispersion coefficient and membrane mass transfer coefficient in the kinetic parameters of different components.

[0091] In another optional embodiment, a dynamic mechanism model of the bed stationary phase with different components is constructed based on the intraparticle diffusion coefficient in the kinetic parameters of different components.

[0092] In a specific example, the diesel aromatics simulated moving bed adsorption separation device involved in this embodiment of the invention is a super-large industrial plant with an annual capacity of 2 million tons. Numerous bed parameters, operating parameters, kinetic parameters, adsorption isotherms, feed composition parameters, and desorbent composition parameters of this industrial plant all affect the device's performance indicators. Among the bed parameters, the total number of beds is 12, with 4 beds in zone one, 3 in zone two, 3 in zone three, and 2 in zone four; the bed diameter is 9000 mm, the bed height is 1720 mm, the bed porosity is 0.31, and the adsorbent radius is 0.35 mm. Among the operating parameters, the step time is 343.8 seconds, and the injection flow rate is 257.65 m³ / s. 3 / h, extractable fluid flow rate 254.60m 3 / h, residual liquid flow rate 431.56m 3 / h, desorbent flow rate 428.51m 3 / h, Zone 1 flow rate 1150.37m 3 / h, Zone 2 flow rate 892.72m 3 / h, flow rate in zone three: 1147.32m³ 3 / h, Zone 4 flow rate 718.81m 3 / h; kinetic parameters include axial dispersion coefficient, membrane mass transfer coefficient, and intraparticle diffusion coefficient; the adsorption isotherm is a multi-component nonlinear competitive adsorption isotherm; feed composition parameters include the concentration of aromatic complex components and the concentration of non-aromatic complex components in diesel oil; desorbent composition parameters include the concentration of strong desorbent and the concentration of weak desorbent.

[0093] In step S21 above, the complex aromatic components in diesel fuel are divided into three lumped components: total monocyclic aromatics, total bicyclic aromatics, and total tricyclic aromatics, with concentrations of 15.20 m%, 9.70 m%, and 2.10%, respectively. The complex non-aromatic components in diesel fuel are divided into two lumped components: total alkanes and total cycloalkanes, with concentrations of 48.70 m% and 24.30 m%, respectively. The desorbent components are divided into two components: strong desorbent and weak desorbent, with concentrations of 30.00 m% and 70.00 m%, respectively. Based on the above steps, dynamic mechanism models of the fluid phase and stationary phase of the bed for different components in step S21 are constructed.

[0094] The performance indicators of the diesel aromatics simulated moving bed adsorption separation industrial device mainly include two aspects: the purity of aromatics in the extract and the purity of non-aromatics in the raffinate. The model output results of Specific Embodiment 1 of this invention are shown in Table 1. The deviations from the performance indicators measured in the actual industrial device are all within 1.3%, fully demonstrating that this invention can comprehensively, systematically, and accurately reveal the quantitative relationship between all these model parameters and device performance indicators, thereby achieving optimized design and operation of the device, and has significant industrial application value.

[0095] Table 1 Comparison of Performance Indicators

[0096]

[0097] Specific Implementation Example 2:

[0099] Specific embodiment 2 only changes one model parameter in specific embodiment 1, changing the adsorbent radius parameter from 0.35mm to 0.70mm; at the same time, all other model parameters, including bed parameters, operating parameters, kinetic parameters, adsorption isotherms, feed composition parameters, desorbent composition parameters, etc., are consistent with specific embodiment 1 or the on-site industrial device.

[0100] Table 2 Comparison of Performance Indicators

[0101]

[0102] The model output results of specific embodiment 2 of the present invention are shown in Table 2. The deviations from the performance indicators measured in the actual industrial device are 10.7% and 4.3%, respectively. This accurately reveals that an increase in the adsorbent radius parameter will significantly reduce the device performance indicators, which has important guiding significance for the optimized design of the device. It should be particularly noted that when those skilled in the art establish bed stationary phase models, the existing modeling methods simplify the bed stationary phase to a homogeneous phase, that is, the component concentration is uniform in the direction of the adsorbent radius at any time. This makes it difficult for the existing modeling methods to reflect the influence of the adsorbent radius parameter on the device performance indicators.

[0103] Based on the same inventive concept, this invention also provides a modeling device for a diesel aromatics simulated moving bed adsorption separation device, referring to... Figure 3 As shown, the modeling apparatus may include:

[0104] The bed dynamic mechanism model construction module 31 is used to construct bed mobile phase dynamic mechanism models and bed stationary phase dynamic mechanism models based on the material balance principle and mass transfer mechanism, respectively, according to the different components of diesel fuel, namely aromatic components, non-aromatic components and desorbent components.

[0105] The discretization module 32 is used to discretize the dynamic mechanism model of the bed mobile phase based on the finite element method and the orthogonal configuration method to obtain the discretized dynamic mechanism model of the bed mobile phase with different components; and to discretize the dynamic mechanism model of the bed stationary phase based on the orthogonal configuration method to obtain the discretized dynamic mechanism model of the bed stationary phase with different components.

[0106] The node model construction module 33 is used to construct node models for different components based on the principle of material balance; among them, the node models include: injection node model, extract node model, desorbent node model and residual liquid node model;

[0107] The bed dynamic mechanism discrete model construction module 34 is used to construct bed dynamic mechanism discrete models with different components based on the bed mobile phase dynamic mechanism discrete model, the bed stationary phase dynamic mechanism discrete model and the node model.

[0108] The module 35 for constructing a discrete model of the dynamic mechanism of the whole-component bed is used to construct a discrete model of the dynamic mechanism of the whole-component bed of the diesel aromatics simulated moving bed adsorption device based on the discrete model of the dynamic mechanism of the bed of different components.

[0109] The optimization module 36 is used to optimize the model parameters of the diesel aromatics simulated moving bed adsorption device based on the discrete model of the dynamic mechanism of the whole component bed.

[0110] In an optional embodiment, the discretization processing module 32 is specifically used for:

[0111] The dimensionless axial spatial coordinates of each bed corresponding to the dynamic mechanism model of the fluid phase in the bed are divided into NE finite elements;

[0112] The first-order discretization matrix and the second-order discretization matrix are derived using NP-order Legendre orthogonal polynomials defined in the interval [0,1].

[0113] Based on the first-order discretization matrix and the second-order discretization matrix, the dynamic mechanism model of the bed flow phase on each finite element is discretized to obtain the discretized model of the dynamic mechanism of the bed flow phase with different components.

[0114] In an optional embodiment, the discretization processing module 32 is further configured to:

[0115] Based on ρ 2 The first-order discretization matrix and the second-order discretization matrix are derived from the (2×NPR) order Jacobian orthogonal polynomial.

[0116] Based on the first-order discretization matrix and the second-order discretization matrix, the dynamic mechanism model of the bed stationary phase is discretized to obtain discrete models of the dynamic mechanism of the bed stationary phase with different components.

[0117] Based on the same inventive concept, this embodiment of the invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the modeling method of the above-described diesel aromatics simulated moving bed adsorption separation device.

[0118] Based on the same inventive concept, this embodiment of the invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the modeling method of the above-mentioned diesel aromatics simulated moving bed adsorption separation device.

[0119] The principles by which the above-mentioned devices, media, and related equipment in the embodiments of the present invention solve the problem are similar to those of the aforementioned methods. Therefore, their implementation can refer to the implementation of the aforementioned methods, and repeated details will not be repeated.

[0120] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention 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 and optical storage) containing computer-usable program code.

[0121] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. 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 illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0122] 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.

[0123] 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.

[0124] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A modeling method for a diesel aromatics simulated moving bed adsorption separation device, characterized in that, The diesel aromatics simulated moving bed adsorption device includes several beds, with adjacent beds connected sequentially along the flow direction of the mobile phase. Inlet nodes, extractor nodes, desorbent nodes, and residual liquid nodes are arranged between the beds, and the nodes move synchronously to the next bed according to a step time along the flow direction of the mobile phase, thereby simulating the movement of the beds in the diesel aromatics simulated moving bed adsorption separation device. The modeling method includes: Based on the principles of material balance and mass transfer mechanism, dynamic mechanism models of the fluid phase and the stationary phase of the bed are constructed for different components, namely aromatic components, non-aromatic components and desorbent components in the diesel fuel. The dynamic mechanism model of the bed fluid phase is discretized based on the finite element method and the orthogonal collocation method to obtain discrete models of the dynamic mechanism of the bed fluid phase with different components. The dynamic mechanism model of the bed stationary phase is discretized based on the orthogonal configuration method to obtain discrete models of the dynamic mechanism of the bed stationary phase with different components. Based on the principle of material balance, node models for different components are constructed respectively; wherein, the node models include: injection node model, extract node model, desorbent node model and residual liquid node model; Based on the discretized dynamic mechanism model of the fluid phase in the bed, the discretized dynamic mechanism model of the stationary phase in the bed, and the node model, discretized dynamic mechanism models of different components in the bed are constructed. Based on the discrete model of the dynamic mechanism of the bed with different components, a discrete model of the dynamic mechanism of the whole component bed of the diesel aromatics simulated moving bed adsorption device is constructed, so as to optimize the model parameters of the diesel aromatics simulated moving bed adsorption device based on the discrete model of the dynamic mechanism of the whole component bed.

2. The method according to claim 1, characterized in that, The discretization of the bed flow phase dynamic mechanism model based on the finite element method and orthogonal collocation method to obtain discrete models of the bed flow phase dynamic mechanism with different components includes: The dimensionless axial spatial coordinates of each bed corresponding to the dynamic mechanism model of the fluid phase in the bed are divided into NE finite elements; The first-order discretization matrix and the second-order discretization matrix are derived using NP-order Legendre orthogonal polynomials defined in the interval [0,1]. Based on the first-order discretization matrix and the second-order discretization matrix, the dynamic mechanism model of the bed flow phase on each finite element is discretized to obtain the discretized model of the dynamic mechanism of the bed flow phase with different components.

3. The method according to claim 1, characterized in that, The discretization of the dynamic mechanism model of the bed stationary phase based on the orthogonal configuration method to obtain discrete models of the dynamic mechanism of the bed stationary phase with different components includes: Based on ρ 2 The first-order discretization matrix and the second-order discretization matrix are derived from the (2×NPR) order Jacobian orthogonal polynomial. Based on the first-order discretization matrix and the second-order discretization matrix, the dynamic mechanism model of the bed stationary phase is discretized to obtain discrete models of the dynamic mechanism of the bed stationary phase with different components.

4. The method according to claim 1, characterized in that, In the dynamic mechanism model of the bed stationary phase, the adsorption amount of different components on the adsorbent is determined by the multi-component nonlinear competitive adsorption isotherm.

5. The method according to claim 4, characterized in that, The multi-component nonlinear competitive adsorption isotherm is a modified multi-component Langmuir-type adsorption isotherm with selective adsorption dual centers. Among them, the selective adsorption dual centers include: aromatic hydrocarbon selective adsorption centers and non-aromatic hydrocarbon selective adsorption centers.

6. The method according to any one of claims 1 to 5, characterized in that, Dynamic mechanism models of bed flow phases with different components were constructed based on the axial dispersion coefficient and membrane mass transfer coefficient in the kinetic parameters of different components.

7. The method according to any one of claims 1 to 5, characterized in that, Dynamic mechanism models of bed stationary phases with different components were constructed based on the intraparticle diffusion coefficient in the kinetic parameters of different components.

8. A modeling device for a diesel aromatics simulated moving bed adsorption separation device, characterized in that, include: The bed dynamic mechanism model construction module is used to construct bed mobile phase dynamic mechanism models and bed stationary phase dynamic mechanism models based on the material balance principle and mass transfer mechanism, respectively, according to the aromatic components, non-aromatic components and desorbent components in the diesel. The discretization module is used to discretize the dynamic mechanism model of the bed flow phase based on the finite element method and the orthogonal collocation method to obtain discrete models of the dynamic mechanism of the bed flow phase with different components. Furthermore, the dynamic mechanism model of the bed stationary phase is discretized based on the orthogonal configuration method to obtain discrete models of the dynamic mechanism of the bed stationary phase with different components; The node model construction module is used to construct node models for different components based on the principle of material balance; wherein, the node models include: injection node model, extract node model, desorbent node model and residual liquid node model; The bed dynamic mechanism discrete model construction module is used to construct bed dynamic mechanism discrete models of different components based on the bed mobile phase dynamic mechanism discrete model, the bed stationary phase dynamic mechanism discrete model and the node model. The module for constructing a discrete model of the dynamic mechanism of the whole-component bed is used to construct a discrete model of the dynamic mechanism of the whole-component bed of the diesel aromatics simulated moving bed adsorption device based on the discrete model of the dynamic mechanism of the bed of different components. The optimization module is used to optimize the model parameters of the diesel aromatics simulated moving bed adsorption device based on the discrete model of the dynamic mechanism of the whole-component bed.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by the processor, the program implements the modeling method for a diesel aromatics simulated moving bed adsorption separation device as described in any one of claims 1 to 7.

10. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the modeling method for a diesel aromatics simulated moving bed adsorption separation device as described in any one of claims 1 to 7.

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