CN119833006A

CN119833006A - Simulation method and system for reaction of preparing styrene by ethylbenzene dehydrogenation

Info

Publication number: CN119833006A
Application number: CN202411902874.6A
Authority: CN
Inventors: 王建平; 杨彩娟; 陈俊士; 朱正文; 江洪波; 陈旭强
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Engineering Co Ltd; Petro CyberWorks Information Technology Co Ltd
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Engineering Co Ltd; Petro CyberWorks Information Technology Co Ltd
Priority date: 2024-12-23
Filing date: 2024-12-23
Publication date: 2025-04-15

Abstract

The invention relates to a simulation method for preparing styrene by ethylbenzene dehydrogenation, which comprises the following steps of firstly) establishing a reaction dynamics equation of chemical reaction, secondly) establishing a material balance equation of each reactant and each reaction product according to the reaction dynamics equation in the first step, thirdly) establishing an energy balance equation according to the material balance equation in the second step, fourthly) establishing a momentum balance equation according to the material balance equation in the second step and the energy balance equation in the third step, and fifthly) adopting the reaction dynamics equation, the material balance equation, the energy balance equation and the momentum balance equation to obtain the content of each component in the reaction product, the temperature of the reaction product and the pressure of the reaction product output by a reactor according to the simulation calculation of the content of each component in raw materials, the temperature of the raw materials, the pressure of the raw materials and the structural parameters of the reactor.

Description

Simulation method and system for reaction of preparing styrene by ethylbenzene dehydrogenation

Technical Field

The invention relates to the technical field of chemical industry, in particular to a simulation method and a simulation system for a reaction for preparing styrene by ethylbenzene dehydrogenation.

Background

In the chemical industry, ethylbenzene dehydrogenation is a process of generating styrene by dehydrogenation reaction with ethylbenzene as a raw material under the action of a catalyst. Styrene is an important organic chemical raw material widely used for producing plastics and synthetic rubber, including Polystyrene (PS), acrylonitrile-butadiene-styrene terpolymer (ABS), styrene-acrylonitrile copolymer (SAN), ion exchange resin, styrene thermoplastic elastomer (SBS), unsaturated polyester and the like.

In the early development stage of the process for preparing styrene by ethylbenzene dehydrogenation, zinc-based and magnesium-based catalysts are adopted, but the zinc-based and magnesium-based catalysts are replaced by iron-potassium-based catalysts with better performance. In recent years, ethylbenzene dehydrogenation catalysts have been further developed and developed in the direction of reducing the potassium content of the catalyst, reducing the water-to-hydrocarbon ratio of the catalyst and improving the life of the catalyst. The lifetime of commercial catalysts is currently typically 2 to 3 years. The technology for preparing styrene by ethylbenzene dehydrogenation mainly comprises a Lummus/UOP technology, a Fina/Badger technology, a BASF technology, a domestic ST technology and the like. Domestic industrial production of styrene starts in the 50 s of 20 th century, and a plurality of devices are introduced and built successively. The university of eastern chemical industry developed an ethylbenzene negative pressure dehydrogenation axial radial reactor in the 90 s, and a domestic ST technology developed in cooperation with the China petrochemical Shanghai petrochemical institute of technology and China petrochemical Shanghai engineering company was successfully built into a plurality of industrial devices, and good operation effects were obtained.

Ethylbenzene dehydrogenation is a process controlled by chemical reaction and diffusion, and has more complex reaction and more influencing factors. It is considered that dehydrogenation of ethylbenzene in the adsorbed state and adjacent vacancies in combination produces hydrogen in the adsorbed state and styrene in the adsorbed state is a control step for determining the reaction rate. The reaction temperature, pressure, water-hydrocarbon ratio and the like have great influence on the reaction yield. Ethylbenzene dehydrogenation reaction kinetics are an important method for discussing the reaction mechanism, and many researchers have studied ethylbenzene dehydrogenation reaction kinetics.

The research on the reaction kinetics of preparing styrene by ethylbenzene dehydrogenation greatly promotes the progress of the process, but the problems that the model relates to the reaction components in insufficient detail, the treatment of a reactor model is not perfect and the like still exist. Firstly, there are few water vapor conversion reactions considered for small molecules. Since the tail gas treatment of ethylbenzene dehydrogenation process needs to be subjected to an absorption and desorption process, if the steam conversion reaction of small molecules is not considered, the predicted calculation of the tail gas composition cannot be performed. In addition, the research on ethylbenzene dehydrogenation reaction often ignores side reactions caused by impurities, and because most of the ethylbenzene fed is sourced from a device for preparing ethylbenzene by catalyzing dry gas, a small amount of cumene can be entrained in the ethylbenzene produced by the process, and alpha-methylstyrene generated by cumene dehydrogenation is extremely easy to self-polymerize, so that the normal operation of a reactor is influenced.

Disclosure of Invention

The invention provides a method and a system for simulating the reaction of preparing styrene by ethylbenzene dehydrogenation in an ST process, which totally comprise 1 main reaction and 8 side reactions, cover the small molecular vapor conversion reaction and the side reaction for generating alpha-methyl styrene, can more comprehensively predict the reaction process, facilitate the full-flow simulation of a styrene device in the later stage, further optimize the system of the device, and improve the benefit of the device and the market competitiveness of the styrene product. The invention is realized by adopting the following technical scheme:

A simulation method for preparing styrene by ethylbenzene dehydrogenation comprises the following steps:

step one), a reaction kinetic equation of the following chemical reaction is established:

Reaction 1, ethylbenzene reacts to generate styrene and hydrogen;

reaction 2, ethylbenzene reacts to generate benzene and ethylene;

Reacting ethylbenzene with hydrogen to generate toluene and methane;

reacting styrene with hydrogen to generate benzene and ethylene;

reacting styrene with hydrogen to generate toluene and methane;

reaction 6, methane reacts with water to generate carbon monoxide and hydrogen;

reaction 7, carbon monoxide reacts with water to generate carbon dioxide and hydrogen;

reaction 8, ethylene reacts with water to generate carbon monoxide and hydrogen;

reacting isopropylbenzene to generate alpha-methyl styrene and hydrogen;

Step two), establishing a material balance equation of each reactant and each reaction product according to the reaction kinetic equation in the step one);

Step three), an energy balance equation is established according to the material balance equation in the step two);

Step four), establishing a momentum balance equation according to the material balance equation in the step two and the energy balance equation in the step three);

and fifthly), adopting the reaction dynamics equation, the material balance equation, the energy balance equation and the momentum balance equation, and obtaining the content of each component in the reaction product output by the reactor, the temperature of the reaction product and the pressure of the reaction product according to the content of each component in the raw material, the temperature of the raw material, the pressure of the raw material and the structural parameters of the reactor which are fed into the reactor through simulation calculation.

Optionally, the reaction kinetics equation includes:

K_P=C1×exp(C2-C3/T-C4×log(T))

Wherein r ₁～r₉ is the reaction rate of 1 to 9 in kmol/(kg.h), kp is the main reaction equilibrium constant in kPa, C1 to C4 is the correlation constant, k _i is the reaction rate constant in kmol/(kg.h.kPa ^m·Kⁿ), wherein m is determined by dimensional analysis and is equal to 1-total number of steps, n is used only in r ₇, the value is 3;k _i0 is the reaction rate factor before the reaction is the same as k _i, E _a is the activation energy in J/mol, b _j is the adsorption constant in kPa ^-1;b_j0 is the adsorption factor before the reaction is the adsorption activation energy in kPa ^-1;Q_j. P _ST is the styrene partial pressure, P _EB is the ethylbenzene partial pressure, P _H2O is the water partial pressure, P _H2 is the hydrogen partial pressure, P _C2H4 is the ethylene partial pressure, P _CH4 is the methane partial pressure, P _CO is the carbon monoxide partial pressure, and P _ISB is the cumene partial pressure

Optionally, the material balance equation is:

Impurity components which do not participate in the reaction, such as paraxylene, paradiethylbenzene, non-aromatic, and the like, and the flow rate change rate is 0:

Wherein F is the component molar flow rate, the unit kmol.h ^-1,r₁～r₉ is the reaction rate of 1-9, the unit kmol.kg ^-1·h^-1, r is the bed radius, m, L is the bed height, m, ρ is the catalyst bulk density, and kg.m ^-3,F_Other represents impurities. F _ST is the styrene molar flow rate, F _TL is the toluene molar flow rate, F _EB is the ethylbenzene molar flow rate, F _BZ is the benzene molar flow rate, F _H2O is the water molar flow rate, F _H2 is the hydrogen molar flow rate, F _C2H4 is the ethylene molar flow rate, F _CH4 is the methane molar flow rate, F _CO is the carbon monoxide molar flow rate, F _CO2 is the carbon dioxide molar flow rate, F _ISB is the cumene molar flow rate, F _AMS is the alpha-methylstyrene molar flow rate, and F _other is the unreacted impurity.

Optionally, the energy balance equation is:

Wherein Δh _j is the change of each reaction enthalpy, j=1 to 9, unit j·mol ^-1;C_pi is the molar constant pressure heat capacity, i=1 to 19, unit j·mol ^-1·K^-1.

Optionally, the momentum balance equation is:

Wherein epsilon is the porosity of the bed, d _p is the equivalent diameter of the specific surface area of the catalyst particles, the unit m and mu are the dynamic viscosity of the mixed gas, the unit Pa.s, and u is the apparent flow rate of the gas, and the unit m.s ^-1.

Optionally, the reactors in the fifth step include a first reactor and a second reactor connected in series, and the reaction product temperature, the reaction product pressure and the reaction product composition of the first reactor and the second reactor are sequentially calculated by using the reaction dynamics equation, the material balance equation, the energy balance equation and the momentum balance equation.

Optionally, the second reactor is provided with a heat exchanger, and the heat exchange temperature of the heat exchanger is calculated by adopting the following formula:

Wherein T _in,steam is the steam inlet temperature, T _out,steam is the steam outlet temperature, K, F _steam is the steam molar flow, kmol.h ^-1,C_p,steam is the steam molar constant pressure heat capacity, J.mol ^-1·K^-1,T_in,Material is the reactant inlet temperature, K, T _out,Material is the reactant outlet temperature, K, F _Material is the reactant molar flow, kmol.h ^-1,C_p,Material is the reactant molar constant pressure heat capacity, and J.mol ^-1·K^-1.

A simulation system for a reaction for preparing styrene by ethylbenzene dehydrogenation, comprising:

The reaction kinetics module is used for calculating the reaction rate of each reaction in the reactor;

the reaction material balance module is used for calculating the flow and the composition of each reaction raw material and each reaction product in the reactor;

the reaction energy balance module is used for calculating the temperature change and the reaction heat in the reactor;

and the reaction momentum balance module is used for calculating the pressure change in the reactor.

The reaction of the reactor comprises:

Ethylbenzene reacts to produce styrene and hydrogen;

Ethylbenzene reacts to produce benzene and ethylene;

ethylbenzene reacts with hydrogen to produce toluene and methane;

styrene and hydrogen react to form benzene and ethylene;

styrene reacts with hydrogen to form toluene and methane;

methane reacts with water to produce carbon monoxide and hydrogen;

Carbon monoxide reacts with water to form carbon dioxide and hydrogen;

Ethylene reacts with water to form carbon monoxide and hydrogen;

the cumene reaction produces alpha-methylstyrene and hydrogen.

Optionally, the reactor comprises a first reactor and a second reactor connected in series.

Optionally, a heat exchanger is disposed on the second reactor, and the system further includes:

And the heat exchange calculation module is used for calculating the heat exchange temperature and the heat exchange load of the heat exchanger.

Compared with the prior art, the invention has the following advantages and effects:

The invention provides a method and a system for simulating the reaction of preparing styrene by ethylbenzene dehydrogenation in an ST process, which are characterized in that a reaction network and a reaction dynamics model comprising 1 main reaction and 8 side reactions are constructed according to the reaction mechanism of preparing styrene by ethylbenzene dehydrogenation, a two-stage serial one-dimensional quasi-homogeneous radial reactor model with intermediate heat exchange is established according to the structural style of an ethylbenzene dehydrogenation reactor in the ST process, and a model equation set comprising reaction material balance, heat balance, reactor pressure drop calculation and intermediate heat exchanger heat exchange calculation is established according to the reaction network and in combination with the reactor model, so that the ethylbenzene dehydrogenation reaction process can be comprehensively simulated and predicted.

Drawings

FIG. 1 is a structural view of a reactor according to the present invention.

Detailed Description

The invention is further described in detail for the purpose of making the objects and technical solutions of the invention more clear. The experimental methods described in the following examples, unless specifically stated otherwise, are conventional methods, and the reagents and materials described herein, unless specifically stated otherwise, are commercially available, as per the techniques or conditions described in the literature in this field or as per the specifications of the product.

Example 1

The invention provides a simulation method for preparing styrene by ethylbenzene dehydrogenation, which comprises the following steps:

Reaction 1, ethylbenzene reacts to generate styrene and hydrogen;

reaction 2, ethylbenzene reacts to generate benzene and ethylene;

Reacting ethylbenzene with hydrogen to generate toluene and methane;

reacting styrene with hydrogen to generate benzene and ethylene;

reacting styrene with hydrogen to generate toluene and methane;

reaction 6, methane reacts with water to generate carbon monoxide and hydrogen;

reacting isopropylbenzene to generate alpha-methyl styrene and hydrogen;

And fifthly), adopting the reaction dynamics equation, the material balance equation, the energy balance equation and the momentum balance equation, and obtaining the contents of all components in the reaction product output by the reactor, the temperature of the reaction product, the pressure of the reaction product and the composition of the reaction product according to the contents of all components in the raw materials, the temperature of the raw materials, the pressure of the raw materials and the structural parameters of the reactor which are fed into the reactor through simulation calculation.

The reactor is shown in fig. 1 as a two-stage series radial reactor model, and comprises a first reactor and a second reactor which are connected in series, wherein a heat exchanger is further arranged at the inlet of the second reactor.

Contemplated equations include:

EB→BZ+C₂H₄ (2)

EB+H₂→TL+CH₄ (3)

ST+H₂→BZ+C₂H₄ (4)

ST+2H₂→TL+CH₄ (5)

CH₄+H₂O→CO+3H₂ (6)

CO+H₂O→CO₂+H₂ (7)

0.5C₂H₄+H₂O→CO+2H₂ (8)

ISB→AMS+H₂ (9)

Wherein EB is ethylbenzene, ST is styrene, TL is toluene, BZ is benzene, ISB is cumene, and AMS is alpha-methylstyrene.

The reaction kinetics equation includes:

K_P=C1×exp(C2-C3/T-C4×log(T))(21)

Wherein r is the reaction rate (kmol/(kg.h)), kp is the main reaction equilibrium constant (kPa), C1-C4 are the correlation constants, and are obtained by inquiring the reaction data of the styrene preparation by ethylbenzene dehydrogenation disclosed in the prior art according to the reaction conditions of the catalyst and the like, k _i is the reaction rate constant (kmol/(kg.h.kPa ^m·Kⁿ), wherein m is determined by dimensional analysis and is equal to 1-total series, n is only r ₇ and has the numerical value of 3), k _i0 is the reaction rate factor before referring to, the unit is the same as k _i, E _a is the activation energy (J/mol), b _j is the adsorption constant (kPa ^-1),b_j0 is the factor before referring to adsorption, and Q _j is the adsorption activation energy (J/mol).

The ethylbenzene dehydrogenation reactor model is a two-stage serial radial reactor model with intermediate heat exchange. The structure of the reactor is shown in figure 1, the catalyst is filled in the annular region of the reactor, ethylbenzene steam is mixed with superheated steam at the inlet of the first dehydrogenation reactor after heat exchange and temperature rise, enters the catalyst bed along the axial direction, and is subjected to dehydrogenation reaction under the condition of negative pressure heat insulation, the outlet temperature of the first dehydrogenation reactor is reduced because of the dehydrogenation of ethylbenzene into endothermic reaction, and enters the catalyst bed of the second dehydrogenation reactor after heat exchange and temperature rise of the intermediate heat exchanger and the superheated steam, so that two-stage negative pressure heat insulation dehydrogenation reaction is realized, and the material flow discharged from the outlet of the second dehydrogenation reactor is the final reaction product.

The mathematical model equation set of the ethylbenzene dehydrogenation reactor comprises a material balance equation, a heat balance equation, a momentum balance equation and an intermediate heat exchanger heat balance equation.

The material balance equation is:

Wherein F is a molar flow rate (kmol/h), r _i is a reaction rate (kmol kg ^-1·h^-1), i=1 to 9, r is a bed radius (m), L is a bed height (m), ρ is a catalyst bulk density (kg/m 3), and Other represents impurities, and specifically comprises o-xylene, m-xylene, p-xylene, o-diethylbenzene, m-diethylbenzene, p-diethylbenzene and non-aromatics.

The energy balance equation is:

Wherein Δh _j is the change in enthalpy of each reaction, j=1 to 9, unit j·mol ^-1,C_pi is the molar constant pressure heat capacity, i=1 to 19, unit j·mol ^-1·K^-1, the energy balance considers 9 reactions and 19 components (including reactants and major impurities, wherein i represents ethylbenzene, styrene, toluene, benzene, water, hydrogen, ethylene, methane, carbon monoxide, carbon dioxide, cumene, α -methylstyrene, o-xylene, m-xylene, p-xylene, o-diethylbenzene, m-diethylbenzene, p-diethylbenzene, non-aromatics in order from 1 to 19). Wherein each reaction heat is as follows:

ΔH₁=-120697-4.56T/K

ΔH₂=-108750+7.95T/K

ΔH₃=53145+13.18T/K

ΔH₄=11929+12.51T/K

ΔH₅=173824+17.74T/K

ΔH₆=-206100

ΔH₇=41000

ΔH₈=-225600

ΔH₉=-119554

the constant pressure heat capacity equation of each component and the mixture is as follows:

C_P,i＝A_i+B_i×T+C_i×T²+D_i×T³

where y _i is the mole fraction, A, B, C, D is the correlation constant, derived from the public database. Momentum loss is based on a pressure drop formula of fluid flowing in an empty circular tube, and specifically comprises the following steps:

Wherein epsilon is the porosity of the bed, d _p is the equivalent diameter of the specific surface area of the catalyst particles, the unit m and mu are the dynamic viscosity of the mixed gas, the unit Pa.s, u is the apparent flow rate of the gas, the unit m.s ^-1, and the viscosity equations of the components and the mixture are as follows:

Wherein μ _i is the viscosity of the pure components, the unit pa·s, C _i is the viscosity-related constant, i=1 to 4, μ _mix is the viscosity of the mixture, the unit pa·s, M _i is the relative molecular mass, i=1 to 19, the unit g·mol ^-1, derived from the public database.

The heat balance equation of the intermediate heat exchanger is:

Test examples

The mathematical equation set in the simulation method comprises component physical properties, property correlation constants, adsorption equilibrium constants and reaction kinetic constants, and all the data are queried from chemical property handbooks, databases and the like.

The feed data for the simulation inputs are shown in table 1.

Table 1 input feed data

The device configuration and catalyst data for the simulation inputs are shown in table 2.

Table 2 input device configuration and catalyst data

The simulated input reaction operation data are shown in Table 3.

Table 3 reaction operation data entered

Project	Unit (B)	Numerical value
			Inlet temperature of the second reactor	°C	615
Second reactor inlet pressure	Kpa	30
			Intermediate heat exchanger steam inlet temperature	°C	814
Steam inlet pressure of intermediate heat exchanger	Kpa	250
			Steam mass flow of intermediate heat exchanger	kg/h	13700

The data in tables 1-3 are input into a mathematical equation set in a simulation method, a fourth-order Dragon-Gregory tower method is selected for solving, and the composition of the obtained reaction product and the comparison result of the temperature drop and the pressure drop of the reactor and the actual plant value are shown in Table 4.

Table 4 comparison of simulation values with plant values

As can be seen from Table 4, the simulated composition of key components such as ethylbenzene, styrene, hydrogen, etc. and the temperature drop and pressure drop results of each reactor are relatively close to the actual plant values, and the composition deviation of byproducts such as benzene, toluene, carbon dioxide, etc. with smaller content is slightly larger.

The invention also provides a simulation system for preparing styrene by ethylbenzene dehydrogenation based on the method, which comprises a reaction dynamics module, a reaction analysis module and a reaction analysis module, wherein the reaction dynamics module is used for calculating the reaction rate of each reaction in the reactor;

the reaction momentum balance module is used for calculating the pressure change in the reactor;

the reaction of the reactor comprises:

Reaction 1, ethylbenzene reacts to generate styrene and hydrogen;

reaction 2, ethylbenzene reacts to generate benzene and ethylene;

Reacting ethylbenzene with hydrogen to generate toluene and methane;

reacting styrene with hydrogen to generate benzene and ethylene;

reacting styrene with hydrogen to generate toluene and methane;

reaction 6, methane reacts with water to generate carbon monoxide and hydrogen;

Reaction 9, cumene reaction to produce alpha-methylstyrene and hydrogen.

The reactor comprises a first reactor and a second reactor which are connected in series, and a heat exchanger is arranged on the second reactor. The heat exchange calculation module is used for calculating the heat exchange temperature and the heat exchange load of the heat exchanger.

It should be noted that the above is only a preferred embodiment of the present invention, and the present invention is not limited to the preferred embodiment, but the present invention is described in detail with reference to the foregoing embodiment, and those skilled in the art may modify the technical solutions described in the foregoing embodiments or substitute some of the technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A simulation method for the dehydrogenation of ethylbenzene to produce styrene, characterized in that it comprises the following steps:

Step 1) Establish the reaction kinetics equation of the following chemical reaction:

Reaction 1: Ethylbenzene reacts to produce styrene and hydrogen;

Reaction 2: Ethylbenzene reacts to produce benzene and ethylene;

Reaction 3: Ethylbenzene and hydrogen react to form toluene and methane;

Reaction 4: Styrene and hydrogen react to produce benzene and ethylene;

Reaction 5: Styrene and hydrogen react to produce toluene and methane;

Reaction 6: Methane and water react to produce carbon monoxide and hydrogen;

Reaction 7: Carbon monoxide reacts with water to produce carbon dioxide and hydrogen;

Reaction 8: Ethylene and water react to produce carbon monoxide and hydrogen;

Reaction 9: Cumene reacts to produce α-methylstyrene and hydrogen;

Step 2) establishing a material balance equation for each reactant and reaction product according to the reaction kinetics equation in step 1); Step 3) establishing an energy balance equation according to the material balance equation in step 2);

Step 4) establishing a momentum balance equation according to the material balance equation in step 2 and the energy balance equation in step 3); Step 5) using the reaction kinetics equation, material balance equation, energy balance equation and momentum balance equation, according to the content of each component in the raw materials fed into the reactor, the raw material temperature, the raw material pressure, and the reactor structural parameters, simulate and calculate the content of each component in the reaction product output by the reactor, the reaction product temperature, and the reaction product pressure.

2. The simulation method for the reaction of ethylbenzene dehydrogenation to styrene according to claim 1, wherein the reaction kinetic equation comprises:

K _P =C1×exp(C2-C3/T-C4×log(T))

Wherein, _r1 ~ _r9 are the reaction rates of reactions 1~9, Kp is the main reaction equilibrium constant, C1~C4 are correlation constants, k _i is the reaction rate constant, k _i0 is the reaction rate pre-exponential factor, E _a is the activation energy, b _j is the adsorption constant, b _j0 is the adsorption pre-exponential factor, Q _j is the adsorption activation energy; P _ST is the partial pressure of styrene, P _EB is the partial pressure of ethylbenzene, P _H2O is the partial pressure of water, P _H2 is the partial pressure of hydrogen, P _C2H4 is the partial pressure of ethylene, P _CH4 is the partial pressure of methane, P _CO is the partial pressure of carbon monoxide, and P _ISB is the partial pressure of isopropylbenzene.

3. The simulation method for the reaction of ethylbenzene dehydrogenation to styrene according to claim 1, wherein the material balance equation is:

For impurity components that do not participate in the reaction, the flow rate change rate is 0:

Wherein F is the component molar flow rate, r ₁ ~ r ₉ are the reaction rates of reactions 1 ~ 9, r is the bed radius, L is the bed height, ρ is the catalyst packing density, F _Other represents impurities; F _ST is the styrene molar flow rate, F _TL is the toluene molar flow rate, F _EB is the ethylbenzene molar flow rate, F _BZ is the benzene molar flow rate, F _H2O is the water molar flow rate, F _H2 is the hydrogen molar flow rate, F _C2H4 is the ethylene molar flow rate, F _CH4 is the methane molar flow rate, F _CO is the carbon monoxide molar flow rate, F _CO2 is the carbon dioxide molar flow rate, F _ISB is the isopropylbenzene molar flow rate, F _AMS is the α-methylstyrene molar flow rate, and F _other is the impurity that does not participate in the reaction.

4. The simulation method for the reaction of ethylbenzene dehydrogenation to styrene according to claim 1, wherein the energy balance equation is:

Where _ΔHj is the molar reaction enthalpy change, j from 1 to 9 represents reactions 1 to 9 in turn; _Cpi is the molar heat capacity at constant pressure, i from 1 to 19 represents the components ethylbenzene, styrene, toluene, benzene, water, hydrogen, ethylene, methane, carbon monoxide, carbon dioxide, isopropylbenzene, α-methylstyrene, o-xylene, m-xylene, p-xylene, o-diethylbenzene, m-diethylbenzene, p-diethylbenzene, and non-aromatics in turn.

5. The simulation method for the reaction of ethylbenzene dehydrogenation to styrene according to claim 1, characterized in that the momentum balance equation is:

Where ε is the bed porosity, _dp is the equivalent diameter of the catalyst particle specific surface area, μ is the dynamic viscosity of the mixed gas, and u is the gas superficial velocity.

6. The simulation method for the dehydrogenation of ethylbenzene to produce styrene according to claim 1 is characterized in that the reactor in the step (e) comprises a first reactor and a second reactor connected in series, and the reaction kinetics equation, material balance equation, energy balance equation and momentum balance equation are used to sequentially calculate the reaction product temperature, reaction product pressure and reaction product composition of the first reactor and the second reactor.

7. The simulation method for the reaction of ethylbenzene dehydrogenation to produce styrene according to claim 6, characterized in that a heat exchanger is provided on the second reactor, and the heat exchange temperature of the heat exchanger is calculated by the following formula:

Wherein, Tin _,steam is the steam inlet temperature, T _out,steam is the steam outlet temperature, F _steam is the steam molar flow rate, C _p,steam is the steam molar heat capacity at constant pressure, Tin _,Material is the reaction material inlet temperature, T _out,Material is the reaction material outlet temperature, F _Material is the reaction material molar flow rate, and C _p,Material is the reaction material molar heat capacity at constant pressure.

8. A simulation system for the reaction of ethylbenzene dehydrogenation to produce styrene, characterized by comprising:

Reaction kinetics module, used to calculate the reaction rates of each reaction in the reactor;

Reaction material balance module, used to calculate the flow and composition of each reaction raw material and reaction product in the reactor;

Reaction energy balance module, used to calculate the temperature change and reaction heat in the reactor;

Reaction momentum balance module, used to calculate the pressure change in the reactor;

The reaction of the reactor includes:

Reaction 1: Ethylbenzene reacts to produce styrene and hydrogen;

Reaction 2: Ethylbenzene reacts to produce benzene and ethylene;

Reaction 3: Ethylbenzene and hydrogen react to form toluene and methane;

Reaction 4: Styrene and hydrogen react to produce benzene and ethylene;

Reaction 5: Styrene and hydrogen react to produce toluene and methane;

Reaction 6: Methane and water react to produce carbon monoxide and hydrogen;

Reaction 8: Ethylene and water react to produce carbon monoxide and hydrogen;

Reaction 9: Isopropylbenzene reacts to produce α-methylstyrene and hydrogen.

9 . The simulation system for the dehydrogenation of ethylbenzene to produce styrene according to claim 8 , wherein the reactor comprises a first reactor and a second reactor connected in series.

10. The simulation system for the reaction of ethylbenzene dehydrogenation to produce styrene according to claim 9, characterized in that a heat exchanger is provided on the second reactor, and the system further comprises:

The heat exchange calculation module is used to calculate the heat exchange temperature and heat exchange load of the heat exchanger.