Modeling method and device for pre-scorching tank type regeneration system

Abstract

The invention discloses a modeling method and device for a pre-charring tank type regeneration system. The modeling method comprises the following steps: S1, establishing a charring reaction kinetic model; s2, establishing a steady-state model of the regeneration system; s3, predicting axial temperature distribution of the regeneration system, composition of regenerated flue gas and catalyst carbon determination according to the steady-state model, and optimizing operation parameters of the regeneration system according to a prediction result; in the step S2, establishment of the steady-state model of the regeneration system comprises establishment of a burning tank steady-state model and establishment of a regenerator steady-state model, in the process of establishing the burning tank steady-state model, the carbon content and the hydrogen content of a catalyst in a burning tank change in the axial direction of the burning tank, the axial temperature distribution of the regeneration system, the composition of regenerated flue gas and catalyst carbon determination can be predicted, and the stability of the regeneration system is improved. Operation of the regeneration system is optimized according to the prediction result, then the scorching effect of the regeneration system is optimized, the operation flexibility of the regeneration system is improved, and tail combustion of the regeneration system is eliminated.

Description

TECHNICAL FIELD

[0001] The present application relates to the chemical technology field, and in particular to a modeling method and device of a front coke burning tank type regeneration system. BACKGROUND

[0002] The catalytic cracking device is a main device for heavy oil lightening in the modern oil refining industry, and is also a core device with higher income in the oil refining industry, and the regeneration process of the catalyst is an important link in the catalytic cracking industrial production, and the main tasks in the industrial operation are to reduce the carbon content of the regenerated catalyst, control the regeneration temperature and balance the heat of the reaction regeneration system.

[0003] At present, the front coke burning tank type two-end regeneration system has been widely applied due to its high coke burning intensity, convenient and flexible operation and other advantages, but the regeneration system also has some problems in application, especially when processing heavy feedstock, the air consumption is large, the operation flexibility is small, and the dilute phase tail combustion is serious, therefore, in order to optimize the coke burning effect of the catalytic cracking regeneration system, improve the operation flexibility of the regeneration system and eliminate the tail combustion of the regeneration system, it is necessary to establish a model of the front coke burning tank type regeneration system. SUMMARY

[0004] The present application aims to provide a modeling method of a front coke burning tank type regeneration system, which optimizes the coke burning effect of the catalytic cracking regeneration system, improves the operation flexibility of the regeneration system and eliminates the tail combustion of the regeneration system.

[0005] In order to achieve the above-mentioned purpose, the specific scheme adopted by the present application is as follows: a method for establishing a steady-state model of a front coke burning tank type regeneration system, comprising the following steps:

[0006] S1, a coke burning reaction kinetics model is established;

[0007] S2, a steady-state model of the regeneration system is established;

[0008] S3, the axial temperature distribution of the regeneration system, the composition of the regeneration flue gas and the carbon content of the catalyst are predicted according to the steady-state model, and the operation parameters of the regeneration system are optimized according to the prediction results;

[0009] In the S2, the establishment of the steady-state model of the regeneration system includes the establishment of a coke burning tank steady-state model and the establishment of a regenerator steady-state model, wherein in the process of establishing the coke burning tank steady-state model, the carbon content and hydrogen content of the catalyst in the coke burning tank change along the axial direction, and the change rate equations of the two are:

[0010]

[0011]

[0012] Where V represents the volume of the burnt tank, Z represents the dimensionless relative distance at the z section in the burnt tank, Z = z / Zp, Z p represents the height of the burnt tank; r1 represents the reaction rate of carbon oxidation to generate CO, r2 represents the reaction rate of carbon oxidation to generate CO2, r3 represents the reaction rate of hydrogen oxidation to generate H2O, k1 represents the reaction rate constant of carbon oxidation to generate CO, k2 represents the reaction rate constant of carbon oxidation to generate CO2, k3 represents the reaction rate constant of hydrogen oxidation to generate H2O, ρ cat Indicates the density of catalyst particles in the dense phase bed, ε cat Volume fraction of burnt tank catalyst, MW C Indicates the molar molecular mass of carbon, MW H represents the molar molecular mass of hydrogen, c i represents the molar concentration of gas component i (i is CO, CO2, H2O, O2 or N2), ε g Indicates the volume fraction of the mixed gas in the burnt tank, v g represents the volume flow rate of the gas in the burnt tank, w C Indicates the carbon content of the catalyst in the burnt tank, w H Indicates the hydrogen content of the catalyst in the burnt tank, n O2 represents the oxygen molar flow rate at the inlet of the charring tank; v g,D Indicates the volume flow rate of gas in the dense bed, F cat represents the catalyst mass flow rate.

[0013] As an optimization scheme for the modeling method of the above-mentioned pre-coking tank regeneration system: carbon burning reaction, hydrogen burning reaction and CO oxidation to generate CO2 reaction occur in the coking tank, carbon burning reaction, hydrogen burning reaction and CO oxidation to generate CO2 reaction occur in the dense phase bed of the regenerator, and CO oxidation to generate CO2 reaction occurs in the dilute phase bed of the regenerator.

[0014] As another optimization scheme for the modeling method of the above-mentioned pre-coking tank regeneration system: In S1, the process of establishing the coking reaction kinetic model is as follows: the reaction equation in the coking tank is:

[0015]

[0016]

[0017]

[0018]

[0019] wherein, r1 represents the reaction rate of carbon element oxidation to generate CO, r2 represents the reaction rate of carbon element oxidation to generate CO2, r3 represents the reaction rate of hydrogen element oxidation to generate H2O, r4 represents the reaction rate of CO oxidation to generate CO2, and the calculation formula of r1, r2, r3 and r4 is:

[0020]

[0021]

[0022]

[0023]

[0024] wherein, k1 represents the reaction rate constant of carbon element oxidation to generate CO, k2 represents the reaction rate constant of carbon element oxidation to generate CO2, k3 represents the reaction rate constant of hydrogen element oxidation to generate H2O, k4 represents the reaction rate constant of CO oxidation to generate CO2, and ρ cat represents the catalyst particle density in the coke-burning tank, ε cat the coke-burning tank catalyst volume fraction, MW C represents the molar molecular mass of carbon element, MW H represents the molar molecular mass of hydrogen element, c i represents the molar concentration of gas component i (i is CO, CO2, H2O, O2).

[0025] As another optimization scheme of the above-mentioned modeling method of the front coke-burning tank type regeneration system, in the S2, the process of establishing the coke-burning tank steady-state model is that the catalyst and gas in the coke-burning tank move together along the axial direction of the coke-burning tank, and the change rate equation of the molar flow rate of each component of the gas in the coke-burning tank along the axial direction is:

[0026]

[0027]

[0028]

[0029]

[0030]

[0031] wherein, V represents the volume of the coke-burning tank, Z represents the dimensionless relative distance at z section in the coke-burning tank, Z=z / Zp, Z prepresents the height of the coke burning tank; r1 represents the reaction rate of carbon element oxidizing to CO, r2 represents the reaction rate of carbon element oxidizing to CO2, r3 represents the reaction rate of hydrogen element oxidizing to H2O, k1 represents the reaction rate constant of carbon element oxidizing to CO, k2 represents the reaction rate constant of carbon element oxidizing to CO2, k3 represents the reaction rate constant of hydrogen element oxidizing to H2O, k4 represents the reaction rate constant of CO oxidizing to CO2, ρ cat represents the density of catalyst particles in the coke burning tank, ε cat coke burning tank catalyst volume fraction, MW C represents the molar molecular mass of carbon element, MW H represents the molar molecular mass of hydrogen element, c i represents the molar concentration of gas component i (i is CO, CO2, H2O, O2 or N2), ε g represents the volume fraction of mixed gas in the coke burning tank, v g represents the volume flow rate of gas in the coke burning tank, Ω RG represents the cross-sectional area of the coke burning tank dense bed, w C represents the carbon content of catalyst in the coke burning tank, w H represents the hydrogen content of catalyst in the coke burning tank;

[0032] The initial value of the molar flow rate of each component of the gas at the inlet of the coke burning tank is:

[0033]

[0034] wherein, n Air represents the molar flow of primary air;

[0035] The initial value of the carbon content and hydrogen content of the catalyst coke is:

[0036]

[0037] wherein, w ck represents the coke content of the catalyst, y C represents the carbon content of the coke, y H represents the hydrogen content of the coke.

[0038] Another optimization scheme of the above-mentioned modeling method of the front coke burning tank type regeneration system is: the gas in the coke burning tank enters the dilute phase bed of the regenerator, and the catalyst enters the dense phase bed of the regenerator.

[0039] Another optimization scheme of the above-mentioned modeling method of the front coke burning tank type regeneration system is: in the S2, the process of establishing the steady-state model of the regenerator is: the material balance of the gas in the dense phase bed is carried out, and the change rate equation of the molar flow rate of each component of the gas along the axial direction is obtained:

[0040]

[0041]

[0042]

[0043]

[0044] wherein, V D represents the volume of the dense bed, Z represents the dimensionless relative distance at the z section of the dense bed, Z = z / Z D , Z D represents the height of the dense bed layer; r 1,D represents the reaction rate of carbon element oxidizing to generate CO in the dense bed, r 2,D represents the reaction rate of carbon element oxidizing to generate CO2 in the dense bed, r 3,D represents the reaction rate of hydrogen element oxidizing to generate H2O in the dense bed, r 4,D represents the reaction rate of CO oxidizing to generate CO2 in the dense bed, k1 represents the reaction rate constant of the reaction of carbon element oxidizing to generate CO, k2 represents the reaction rate constant of the reaction of carbon element oxidizing to generate CO2, k3 represents the reaction rate constant of the reaction of hydrogen element oxidizing to generate H2O, k4 represents the reaction rate constant of the reaction of CO oxidizing to generate CO2, p cat represents the catalyst particle density in the dense bed, ε cat,D dense bed catalyst volume fraction, MW C represents the molar molecular mass of carbon element, MW H represents the molar molecular mass of hydrogen element, c i,D represents the molar concentration of gas component i (i is CO, CO2, H2O, O2 or N2) in the dense bed, v g,D represents the volume flow rate of gas in the dense bed, w C,D represents the carbon content of catalyst in the dense bed, w H,D represents the hydrogen content of catalyst in the dense bed;

[0045]

[0046]

[0047] wherein, represents the carbon content on the catalyst at the outlet of the coking pot, w represents the hydrogen content on the catalyst at the outlet of the coking pot;

[0048] The initial values of the molar flow rates of each component are:

[0049]

[0050] wherein, nV Air2 represents the molar flow rate of fluidizing air at the inlet of the regenerator;

[0051] The material balance of the gas in the dilute phase bed is calculated to obtain the rate equation of the molar flow rate of each component of the gas along the axial direction:

[0052]

[0053]

[0054]

[0055]

[0056]

[0057] wherein, V F represents the volume of the dilute phase bed, Z represents the dimensionless relative distance at the z cross section of the dilute phase bed, Z=z / Z F , Z F represents the height of the dilute phase bed; r 1,F represents the reaction rate of carbon element oxidation to generate CO in the dilute phase bed, r 2,F represents the reaction rate of carbon element oxidation to generate CO2 in the dilute phase bed, r 3,F represents the reaction rate of hydrogen element oxidation to generate H2O in the dilute phase bed, r 4,F represents the reaction rate of CO oxidation to generate CO2 in the dilute phase bed, k1 represents the reaction rate constant of the reaction of carbon element oxidation to generate CO, k2 represents the reaction rate constant of the reaction of carbon element oxidation to generate CO2, k3 represents the reaction rate constant of the reaction of hydrogen element oxidation to generate H2O, k4 represents the reaction rate constant of the reaction of CO oxidation to generate CO2, c i,F represents the molar concentration of the gas component i (i is CO, CO2, H2O, O2 or N2) in the dilute phase bed, v g,F represents the volume flow rate of the gas in the dilute phase bed;

[0058] The molar flow rate of each component of the gas at the inlet of the dilute phase bed is:

[0059]

[0060] wherein, represents the molar flow rate of each component of the gas at the outlet of the dense phase bed, represents the molar flow rate of each component of the gas at the outlet of the coke-burning tank.

[0061] Another optimization scheme of the above-mentioned modeling method of the pre-coking tank type regeneration system: the axial temperature distribution of the regeneration system includes the axial temperature distribution of the coke-burning tank, and the calculation formula is:

[0062]

[0063] wherein m g represents the mass of gas in the coke burning tank, m cat represents the mass of catalyst in the coke burning tank, C p,g represents the specific heat of gas in the coke burning tank, C p,cat represents the specific heat of catalyst in the coke burning tank, Q react represents the heat of reaction.

[0064] As another optimization scheme of the modeling method of the aforementioned pre-coke burning tank type regeneration system, the catalyst carbon content is:

[0065]

[0066] wherein, represents the coke content on the spent catalyst, F cat represents the mass flow of the spent catalyst.

[0067] A modeling device of a pre-coke burning tank type regeneration system, which is used for the aforementioned modeling method, comprises a model establishing module and a processing module, the model establishing module is used for establishing a coke burning reaction kinetics model, a coke burning tank steady state model and a regenerator steady state model, and the processing module is used for calculating the axial temperature distribution of the regeneration system, the composition of the regeneration flue gas and the catalyst carbon content.

[0068] An electronic device comprising a processor and a memory, the memory storing computer readable instructions that, when executed by the processor, perform the steps of the aforementioned modeling method.

[0069] Compared with the prior art, the present application has the following beneficial effects: the present application provides a modeling method of a pre-coke burning tank type regeneration system, which models the coke burning tank and the regenerator, can predict the axial temperature distribution of the regeneration system, the composition of the regeneration flue gas and the catalyst carbon content, optimizes the operation of the regeneration system according to the prediction results, and further optimizes the coke burning effect of the regeneration system, improves the operation flexibility of the regeneration system and eliminates the tail combustion of the regeneration system. BRIEF DESCRIPTION OF DRAWINGS

[0070] Figure 1 is a schematic diagram of a regeneration system;

[0071] Figure 2 is the influence of the main air volume on the catalyst carbon content and the temperature of the dilute phase bed of the regenerator;

[0072] Figure 3 is the influence of the temperature of the coke burning tank on the catalyst carbon content and the temperature of the dilute phase bed of the regenerator;

[0073] Figure 4The influence of the dense phase bed temperature of the regenerator on the catalyst carbon content and the influence of the dilute phase bed temperature of the regenerator. DETAILED DESCRIPTION

[0074] The technical solutions of the present application are further described in detail below in combination with specific embodiments. The parts not described and disclosed in detail in the following embodiments of the present application should be understood as the prior art known or should be known by the skilled in the art.

[0075] Embodiment 1

[0076] A modeling method of a front coke burning tank type regeneration system, the regeneration system comprising a coke burning tank and a regenerator, the deactivated catalyst entering the coke burning tank from the bottom of the coke burning tank and mixing with the main air and flowing out from the top of the coke burning tank, the flue gas generated in the coke burning tank entering the dilute phase bed of the regenerator, and the catalyst flowing out from the coke burning tank entering the dense phase bed of the regenerator, the modeling method comprising the following steps:

[0077] S1, a coke burning reaction kinetics model is established; the coke attached to the surface of the deactivated catalyst is a mixture mainly comprising carbon elements (C) and hydrogen elements (H), the carbon elements are oxidized to generate CO and CO2, and the hydrogen elements are oxidized to generate H2O in the combustion reaction process, the generated CO continues to be oxidized to generate CO2, and the reaction rate functions of the above four reactions are respectively established, and the nitrogen, sulfur and other elements in the coke are ignored when the coke burning reaction kinetics is described.

[0078] Specifically, the main air and the deactivated catalyst pass through the coke burning tank in the form of piston flow, i.e., no radial diffusion and no axial return, i.e., the coke burning reaction, the hydrogen burning reaction and the CO oxidation reaction to generate CO2 occur in the coke burning tank; the catalyst and the gas pass through the regenerator in the form of full mixing flow, i.e., the bottom of the regenerator is the dense phase bed, the top of the regenerator is the dilute phase bed, and the coke burning reaction, the hydrogen burning reaction and the CO oxidation reaction to generate CO2 occur in the dense phase bed of the regenerator, and the CO oxidation reaction to generate CO2 occurs in the dilute phase bed of the regenerator.

[0079] The process of establishing the coke burning reaction kinetics model is that the reaction equations in the coke burning tank and the regenerator are as follows:

[0080]

[0081]

[0082]

[0083]

[0084] Wherein, r1 represents the reaction rate of the carbon element oxidation to generate CO, the unit is kmolC / (m 3cat·s); r2 represents the reaction rate of carbon oxidation to generate CO2, and its unit is kmolC / (m 3 cat·s); r3 represents the reaction rate of hydrogen oxidation to generate H2O, the unit is kmolH / (m 3 cat·s); r4 represents the reaction rate of CO oxidation to CO2, unit is kmolC / (m 3 cat·s), the calculation formulas of r1, r2, r3, and r4 are:

[0085]

[0086]

[0087]

[0088]

[0089] Where k1 represents the reaction rate constant of the oxidation of carbon to CO, and the unit is m 3 / (kmol·s); k2 represents the reaction rate constant of the oxidation of carbon to CO2, with the unit of m 3 / (kmol·s); k3 represents the reaction rate constant of the oxidation of hydrogen to generate H2O, with the unit of m 3 / (kmol·s); k4 represents the reaction rate constant of the oxidation of CO to CO2, with the unit of m 3 / (kmol·s);ρ cat Indicates the density of catalyst particles in the burnt tank, in kg·m -3 , ε cat Indicates the volume fraction of catalyst in the burnt tank, MW C Indicates the molar molecular mass of carbon element, in kg / kmol; MW H Indicates the molar molecular mass of hydrogen element, the unit is kg / kmol; c i Indicates the molar concentration of gas component i (i is CO, CO2, H2O, O2), the unit is kmol / m 3 .

[0090] Catalyst volume fraction ε in the burnt tank or regenerator cat for:

[0091]

[0092] Among them, v g Indicates the volume flow rate of gas in the coke tank or regenerator, unit: m 3 ·s -1 ;Ω RGrepresents the cross-sectional area of the coking drum or the dense bed.

[0093] ε represents the volume fraction of mixed gas in the coking drum or the regenerator g is:

[0094] ε g = (1-ε cat )

[0095] The calculation formula of the reaction rate constant is obtained according to the Arrhenius equation:

[0096]

[0097] wherein, k i0 represents the pre-exponential factor of the reaction, E i represents the activation energy of the reaction, T represents the regeneration temperature, T* represents the reference regeneration temperature, and R represents the ideal gas constant, R = 8.314 kJ / (kmol·K).

[0098] The molar concentration c i of the gas is:

[0099]

[0100] wherein, n i represents the molar flow rate of each component of the gas, with the unit of kmol·s -1 ; v g represents the volume flow rate of the gas in the coking drum or the regenerator, with the unit of m 3 ·s -1 .

[0101] S2, a steady-state model of the regeneration system is established,

[0102] S3, the axial temperature distribution of the regeneration system, the composition of the regeneration flue gas and the carbon content of the catalyst are predicted according to the steady-state model, and the operation parameters of the regeneration system are optimized according to the prediction results.

[0103] Specifically, in S2, the establishment of the steady-state model of the regeneration system includes the establishment of the steady-state model of the coking drum and the establishment of the steady-state model of the regenerator, wherein the process of establishing the steady-state model of the coking drum is that the catalyst and the gas in the coking drum move together along the axial direction of the coking drum, the gas in the coking drum includes the main air (O2 and N2) and the CO, CO2 and H2O generated by the coking reaction, the material balance of the gas in the coking drum is calculated, and the change rate equation of the molar flow rate of each component of the gas along the axial direction is obtained as:

[0104]

[0105]

[0106]

[0107]

[0108]

[0109] wherein V represents the volume of the coke burning tank, in m 3 ; Z represents the dimensionless relative distance at z section in the coke burning tank, Z = z / Z p , Z p represents the height of the coke burning tank, in m; r1 represents the reaction rate of carbon element oxidizing to generate CO, r2 represents the reaction rate of carbon element oxidizing to generate CO2, r3 represents the reaction rate of hydrogen element oxidizing to generate H2O, k1 represents the reaction rate constant of carbon element oxidizing to generate CO, k2 represents the reaction rate constant of carbon element oxidizing to generate CO2, k3 represents the reaction rate constant of hydrogen element oxidizing to generate H2O, k4 represents the reaction rate constant of CO oxidizing to generate CO2, p cat represents the catalyst particle density in the coke burning tank, ε cat the coke burning tank catalyst volume fraction, MW C represents the molar molecular mass of carbon element, MW H represents the molar molecular mass of hydrogen element, c i represents the molar concentration of gas component i (i is CO, CO2, H2O, O2 or N2), ε g represents the volume fraction of mixed gas in the coke burning tank, v g represents the volume flow rate of gas in the coke burning tank, Ω RG represents the cross-sectional area of the coke burning tank dense bed, w C represents the carbon content of catalyst in the coke burning tank, w H represents the hydrogen content of catalyst in the coke burning tank;

[0110] The carbon content and hydrogen content of catalyst in the coke burning tank change along the axial direction, and the material balance of carbon and hydrogen of coke in the coke burning tank is obtained to obtain the change rate equation of carbon and hydrogen of coke along the axial direction:

[0111]

[0112]

[0113] wherein V represents the volume of the coke burning tank, Z represents the dimensionless relative distance at z section in the coke burning tank, Z = z / Zp, Z prepresents the height of the coke burning pot; r1 represents the reaction rate of carbon element oxidizing to CO, r2 represents the reaction rate of carbon element oxidizing to CO2, r3 represents the reaction rate of hydrogen element oxidizing to H2O, k1 represents the reaction rate constant of carbon element oxidizing to CO, k2 represents the reaction rate constant of carbon element oxidizing to CO2, k3 represents the reaction rate constant of hydrogen element oxidizing to H2O, p cat represents the catalyst particle density in the coke burning pot, ε cat coke burning pot catalyst volume fraction, MW C represents the molar molecular mass of carbon element, MW H represents the molar molecular mass of hydrogen element, c i represents the molar concentration of gas component i (i is CO, CO2, H2O, O2 or N2), ε g represents the mixed gas volume fraction in the coke burning pot, v g represents the volume flow rate of gas in the coke burning pot, w C represents the carbon content of catalyst in the coke burning pot, w H represents the hydrogen content of catalyst in the coke burning pot, n O2 represents the molar flow rate of oxygen at the inlet of the coke burning pot; v g,D represents the gas volume flow in the coke burning pot, F cat represents the catalyst mass flow.

[0114] The initial values of the molar flow rates of each component of the gas at the inlet of the coke burning pot are:

[0115]

[0116] wherein, n Air represents the molar flow of primary air;

[0117] The initial values of the carbon content and hydrogen content in the catalyst coke are:

[0118]

[0119] wherein, w ck represents the coke content of catalyst, y C represents the carbon content of coke, y H represents the hydrogen content of coke.

[0120] The carbon content and hydrogen content on the catalyst at the outlet of the coke burning pot are both calculated by the coke burning pot steady-state model. The change of temperature along the axial direction in the coke burning pot is calculated according to the energy conservation, i.e. the calculation formula of the axial temperature distribution of the coke burning pot is:

[0121]

[0122] ​

[0123] wherein m g represents the mass of gas in the coke burning tank, in kg; m cat represents the mass of catalyst in the coke burning tank, in kg; C p,g represents the specific heat of gas in the coke burning tank, in kJ·(kg·K) -1 ; C p,cat represents the specific heat of catalyst in the coke burning tank, in kJ·(kg·K) -1 ; Q react represents the reaction heat.

[0124] The reaction heat Q react is calculated by the following formula:

[0125]

[0126] wherein n i represents the molar flow rate of each component of gas (i is CO, CO2, H2O), in kmol·s -1 .

[0127] A steady-state model of the regenerator is established, and the gas in the coke burning tank enters the dilute phase bed of the regenerator, and the catalyst enters the dense phase bed of the regenerator. Material balance is performed on the gas in the dense phase bed, and the height of the dense phase bed is set to be constant, to obtain the change rate equation of the molar flow rate of each component of gas along the axial direction:

[0128]

[0129]

[0130]

[0131]

[0132] wherein V D represents the volume of the dense phase bed, Z represents the dimensionless relative distance at the z cross section of the dense phase bed, Z = z / Z D , Z D represents the height of the dense phase bed; r 1,D represents the reaction rate of carbon element oxidation to generate CO in the dense phase bed, r 2,D represents the reaction rate of carbon element oxidation to generate CO2 in the dense phase bed, r 3,D represents the reaction rate of hydrogen element oxidation to generate H2O in the dense phase bed, r 4,DThe reaction rate of CO oxidation to CO2 in the dense phase bed, k1 represents the reaction rate constant of carbon element oxidation to CO, k2 represents the reaction rate constant of carbon element oxidation to CO2, k3 represents the reaction rate constant of hydrogen element oxidation to H2O, k4 represents the reaction rate constant of CO oxidation to CO2, ρ cat The catalyst particle density in the dense phase bed is represented by ε cat,D The catalyst volume fraction in the dense phase bed is represented by MW C The molar molecular mass of carbon element is represented by MW H The molar molecular mass of hydrogen element is represented by c i,D The molar concentration of gas component i (i is CO, CO2, H2O, O2 or N2) in the dense phase bed is represented by v g,D The volume flow rate of gas in the dense phase bed is represented by w C,D The carbon content of catalyst in the dense phase bed is represented by w H,D The hydrogen content of catalyst in the dense phase bed is represented by w

[0133] The carbon content and hydrogen content of catalyst in the dense phase bed of the regenerator are respectively:

[0134]

[0135]

[0136] wherein, The carbon content of catalyst at the outlet of the decoking tank is represented by w The hydrogen content of catalyst at the outlet of the decoking tank is represented by w

[0137] The initial value of the molar flow rate of each component is:

[0138]

[0139] wherein, n Air2 The molar flow of fluidization air at the inlet of the regenerator is represented by w

[0140] For the gas in the dilute phase bed, part of which comes from the dense phase bed of the regenerator and another part comes from the decoking tank, the material balance of the gas in the dilute phase bed is carried out to obtain the change rate equation of the molar flow rate of each component of the gas along the axial direction:

[0141]

[0142]

[0143]

[0144]

[0145]

[0146] wherein V F represents the volume of the dilute phase bed, Z represents the dimensionless relative distance at the z cross section of the dilute phase bed, Z = z / Z F , Z F represents the dilute phase bed layer height; r 1,F represents the reaction rate of carbon element oxidation to generate CO in the dilute phase bed, r 2,F represents the reaction rate of carbon element oxidation to generate CO2 in the dilute phase bed, r 3,F represents the reaction rate of hydrogen element oxidation to generate H2O in the dilute phase bed, r 4,F represents the reaction rate of CO oxidation to generate CO2 in the dilute phase bed, k1 represents the reaction rate constant of carbon element oxidation to generate CO, k2 represents the reaction rate constant of carbon element oxidation to generate CO2, k3 represents the reaction rate constant of hydrogen element oxidation to generate H2O, k4 represents the reaction rate constant of CO oxidation to generate CO2, c i,F represents the molar concentration of gas component i (i is CO, CO2, H2O, O2 or N2) in the dilute phase bed, v g,F represents the volume flow rate of gas in the dilute phase bed;

[0147] According to the continuity of gas flow, the molar flow rate of gas at the inlet of the dilute phase bed is equal to the sum of the molar flow rate of gas at the outlet of the coke-burning tank and the molar flow rate of gas at the outlet of the dense phase bed, i.e. the molar flow rate of each component of gas at the inlet of the dilute phase bed is:

[0148]

[0149] wherein, represents the molar flow rate of each component of gas at the outlet of the dense phase bed, represents the molar flow rate of each component of gas at the outlet of the coke-burning tank.

[0150] The flue gas generated by the regeneration system flows out from the outlet of the dilute phase bed of the regenerator, and the calculation formula of the proportion of each component of gas in the flue gas is:

[0151]

[0152] According to the flue gas flow rate at the outlet of the regenerator, the calculation formula of the carbon content of the catalyst is obtained:

[0153]

[0154] wherein, represents the coke content of the spent catalyst, F cat represents the mass flow rate of the spent catalyst.

[0155] The above model can be used to predict the influence of operating conditions on the axial temperature distribution of the regeneration system, the composition of the regeneration flue gas and the catalyst carbon content, that is, the axial temperature distribution of the regeneration system, the composition of the regeneration flue gas and the catalyst carbon content can be predicted, and the operation of the regeneration system can be optimized according to the prediction results, thereby optimizing the burning effect of the regeneration system, improving the operational flexibility of the regeneration system and eliminating the tail combustion of the regeneration system.

[0156] Example 2

[0157] A modeling approach was used to predict the effects of main air volume on catalyst carbonization and regenerator dilute bed temperature.

[0158] Assume that the regeneration system is in thermal equilibrium, the catalyst flow rate is 210 kg / s, the catalyst carbon content is 1.0 w%, the burnt tank temperature is 660 ° C, the regenerator dense phase bed temperature is 700 ° C, and the main air volume is predicted to affect the catalyst carbon content (i.e. Figure 2 The regenerator carbon) and the regenerator dilute phase bed temperature (i.e. Figure 2 The influence of the secondary dilute phase temperature in Figure 2 .like Figure 2 As shown, as the main air volume increases from 60000m 3 / h increased to 100000m 3 / h, the catalyst carbon content decreased from 0.23w% to 0.16w%, and the temperature of the regenerator dilute bed increased from 743℃ to 762℃. That is, increasing the main air volume can reduce the catalyst carbon content, but it will increase the temperature of the regenerator dilute bed. Therefore, adjusting the main air volume cannot reduce the catalyst carbon content and the regenerator dilute bed temperature at the same time.

[0159] Example 3

[0160] A modeling approach was used to predict the effect of the burnout drum temperature on the catalyst carbon set and the regenerator dilute bed temperature.

[0161] According to Example 2, the difference is that the main air volume of the coke tank is set to 100000m 3 / h, predict the effect of the burnt tank temperature on the catalyst carbon content (i.e. Figure 3 The regenerator carbon) and the regenerator dilute phase bed temperature (i.e. Figure 3 The influence of the secondary dilute phase temperature in Figure 3 .like Figure 3 As shown in the figure, as the temperature of the coking tank increases from 660℃ to 700℃, the catalyst carbon content decreases from 0.16w% to 0.01w%, and the temperature of the regenerator dilute bed first increases from 761℃ to 765℃ and then decreases to 763℃. That is, increasing the temperature of the coking tank can simultaneously reduce the catalyst carbon content and the regenerator dilute bed temperature.

[0162] Example 4

[0163] The modeling method is used to predict the effect of regenerator dense bed temperature on catalyst carbonation and regenerator dilute bed temperature.

[0164] According to Example 3, except that the coke burning pot temperature is set to 700℃, the effect of regenerator dense bed temperature on catalyst carbonation (i.e. Figure 4 the catalyst carbonation in the regenerator) and regenerator dilute bed temperature (i.e. Figure 4 the regenerator dilute bed temperature in the regenerator) is predicted. Figure 4 As shown in Figure 4 , as the regenerator dense bed temperature is increased from 660 to 700℃, the catalyst carbonation does not change, and the regenerator dilute bed temperature is increased from 720 to 765℃, i.e. decreasing the regenerator dense bed temperature has no effect on catalyst carbonation, but will decrease the regenerator dilute bed temperature.

[0165] In summary, by using the model of the regeneration system to obtain the operating conditions that simultaneously decrease catalyst carbonation and regenerator dilute bed temperature, the coke burning effect of the device is improved and the tail combustion phenomenon of the device is eliminated.

[0166] Example 5

[0167] A modeling device of a front coke burning pot type regeneration system, which is used for the modeling method described in Example 1, comprises a model establishing module and a processing module, the model establishing module is used to establish a coke burning reaction kinetics model, a coke burning pot steady state model and a regenerator steady state model, and the processing module is used to calculate the temperature distribution of the regeneration system, the composition of the regeneration flue gas and the catalyst carbonation.

[0168] Example 6

[0169] An electronic device comprising a processor and a memory, the memory storing computer readable instructions that, when executed by the processor, perform the steps of the modeling method described in Example 1.

[0170] The above description of disclosed embodiments enables one of ordinary skill in the art to make and use the application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A modeling method for a pre-coke tank regeneration system, comprising the following steps: S1, establish the kinetic model of charring reaction; S2, establish a steady-state model of the regeneration system; S3, predicting the axial temperature distribution of the regeneration system, the composition of the regeneration flue gas, and the catalyst carbon content based on the steady-state model, and optimizing the operating parameters of the regeneration system based on the prediction results; It is characterized in that: in said S2, establishing the steady-state model of the regeneration system includes establishing a steady-state model of the coke tank and establishing a steady-state model of the regenerator, wherein, in the process of establishing the steady-state model of the coke tank, the carbon content and hydrogen content of the catalyst in the coke tank change along its axial direction, and the rate of change equation of the two is: Where V represents the volume of the burnt tank, Z represents the dimensionless relative distance at the z section in the burnt tank, Z = z / Zp, Z p represents the height of the burnt tank; r1 represents the reaction rate of carbon oxidation to generate CO, r2 represents the reaction rate of carbon oxidation to generate CO2, r3 represents the reaction rate of hydrogen oxidation to generate H2O, k1 represents the reaction rate constant of carbon oxidation to generate CO, k2 represents the reaction rate constant of carbon oxidation to generate CO2, k3 represents the reaction rate constant of hydrogen oxidation to generate H2O, ρ cat Indicates the density of catalyst particles in the burnt tank, ε cat Volume fraction of burnt tank catalyst, MW C Indicates the molar molecular mass of carbon, MW H represents the molar molecular mass of hydrogen, c i represents the molar concentration of gas component i (i is CO, CO2, H2O, O2 or N2), ε g Indicates the volume fraction of the mixed gas in the burnt tank, v g represents the volume flow rate of the gas in the burnt tank, w C Indicates the carbon content of the catalyst in the burnt tank, w H Indicates the hydrogen content of the catalyst in the burnt tank, n O2 represents the oxygen molar flow rate at the inlet of the charring tank; v g,D Indicates the volume flow rate of gas in the burnt tank, F cat Indicates the mass flow rate of catalyst to be regenerated.

2. The modeling method of a pre-coke tank regeneration system according to claim 1, characterized in that: Carbon burning reaction, hydrogen burning reaction and CO oxidation to generate CO2 reaction occur in the coke tank, carbon burning reaction, hydrogen burning reaction and CO oxidation to generate CO2 reaction occur in the dense phase bed of the regenerator, and CO oxidation to generate CO2 reaction occurs in the dilute phase bed of the regenerator.

3. The modeling method of a pre-coke tank regeneration system according to claim 1, characterized in that: In S1, the process of establishing the scorch reaction kinetic model is as follows: the reaction equation in the scorch tank is: Among them, r1 represents the reaction rate of carbon oxidation to generate CO, r2 represents the reaction rate of carbon oxidation to generate CO2, r3 represents the reaction rate of hydrogen oxidation to generate H2O, and r4 represents the reaction rate of CO oxidation to generate CO2. The calculation formulas of r1, r2, r3, and r4 are: Among them, k1 represents the reaction rate constant of the reaction of carbon element oxidation to CO, k2 represents the reaction rate constant of the reaction of carbon element oxidation to CO2, k3 represents the reaction rate constant of the reaction of hydrogen element oxidation to H2O, k4 represents the reaction rate constant of the reaction of CO oxidation to CO2, ρ cat Indicates the density of catalyst particles in the burnt tank, ε cat Volume fraction of burnt tank catalyst, MW C Indicates the molar molecular mass of carbon, MW H represents the molar molecular mass of hydrogen, c i Represents the molar concentration of gas component i (i is CO, CO2, H2O, O2).

4. The modeling method of a pre-coke tank regeneration system according to claim 1, characterized in that: In S2, the process of establishing the steady-state model of the coke tank is that the catalyst and gas in the coke tank move together along the axial direction of the coke tank, and the rate of change equation of the molar flow rate of each component of the gas in the coke tank along the axial direction is: Where V represents the volume of the burnt tank, Z represents the dimensionless relative distance at the z section in the burnt tank, Z = z / Zp, Z p represents the height of the burnt tank; r1 represents the reaction rate of carbon oxidation to generate CO, r2 represents the reaction rate of carbon oxidation to generate CO2, r3 represents the reaction rate of hydrogen oxidation to generate H2O, k1 represents the reaction rate constant of carbon oxidation to generate CO, k2 represents the reaction rate constant of carbon oxidation to generate CO2, k3 represents the reaction rate constant of hydrogen oxidation to generate H2O, k4 represents the reaction rate constant of CO oxidation to generate CO2, ρ cat Indicates the density of catalyst particles in the burnt tank, ε cat Volume fraction of burnt tank catalyst, MW C Indicates the molar molecular mass of carbon, MW H represents the molar molecular mass of hydrogen, c i represents the molar concentration of gas component i (i is CO, CO2, H2O, O2 or N2), ε g Indicates the volume fraction of the mixed gas in the burnt tank, v g represents the volume flow rate of the gas in the burnt tank, Ω RG represents the cross-sectional area of ​​the dense phase bed in the coke tank, w C Indicates the carbon content of the catalyst in the burnt tank, w H Indicates the hydrogen content of the catalyst in the burnt tank; The initial values ​​of the molar flow rates of the gas components at the inlet of the char tank are: Among them, n Air represents the main wind molar flow rate; The initial values ​​of carbon content and hydrogen content in catalyst coke are: Among them, w ck Indicates the coke content of the catalyst, y C Indicates the carbon content of coke, y H Indicates the hydrogen content of coke.

5. The modeling method of a pre-coke tank regeneration system according to claim 1, characterized in that: The gas in the coke tank enters the dilute phase bed of the regenerator, and the catalyst enters the dense phase bed of the regenerator.

6. The modeling method of a pre-coke tank regeneration system according to claim 5, characterized in that: In S2, the process of establishing the steady-state model of the regenerator is to perform material balance on the gas in the dense phase bed to obtain the equation for the rate of change of the molar flow rate of each gas component along the axial direction: Among them, V D represents the volume of the dense bed, Z represents the dimensionless relative distance at the z section of the dense bed, Z=z / Z D , Z D Indicates the height of dense phase bed; r 1,D Indicates the reaction rate of carbon oxidation to CO in a dense bed, r 2,D Indicates the reaction rate of carbon oxidation to CO2 in a dense bed, r 3,D Indicates the reaction rate of hydrogen oxidation to generate H2O in the dense phase bed, r 4,D represents the reaction rate of CO oxidation to CO2 in the dense phase bed, k1 represents the reaction rate constant of carbon oxidation to CO, k2 represents the reaction rate constant of carbon oxidation to CO2, k3 represents the reaction rate constant of hydrogen oxidation to H2O, k4 represents the reaction rate constant of CO oxidation to CO2, ρ cat Indicates the density of catalyst particles in the dense phase bed, ε cat,D Dense bed catalyst volume fraction, MW C Indicates the molar molecular mass of carbon, MW H represents the molar molecular mass of hydrogen, c i,D represents the molar concentration of gas component i in the dense bed (i is CO, CO2, H2O, O2 or N2), v g,D represents the volume flow rate of gas in the dense bed, w C,D Indicates the carbon content of the catalyst in the dense phase bed, w H,D Indicates the hydrogen content of the catalyst in the dense bed; in, Indicates the carbon content on the catalyst at the outlet of the burnt tank. Expressed as the hydrogen content on the catalyst at the outlet of the burnt tank; The initial values ​​of the molar flow rates of each component are: Among them, n Air2 represents the molar flow rate of fluidizing air at the regenerator inlet; By performing material balance on the gas in the dilute bed, we can obtain the equation for the rate of change of the molar flow rate of each gas component along the axial direction: Among them, V F Represents the volume of the dilute phase bed, Z represents the dimensionless relative distance at the z section of the dilute phase bed, Z=z / Z F , Z F represents the dilute phase bed height; r 1,F represents the reaction rate of carbon oxidation to CO in a dilute bed, r 2,F represents the reaction rate of carbon oxidation to CO2 in a dilute bed, r 3,F Indicates the reaction rate of hydrogen oxidation to generate H2O in the dilute phase bed, r 4,F represents the reaction rate of CO oxidation to CO2 in the dilute phase bed, k1 represents the reaction rate constant of carbon oxidation to CO, k2 represents the reaction rate constant of carbon oxidation to CO2, k3 represents the reaction rate constant of hydrogen oxidation to H2O, k4 represents the reaction rate constant of CO oxidation to CO2, c i,F represents the molar concentration of gas component i in the dilute bed (i is CO, CO2, H2O, O2 or N2), v g,F It represents the volume flow rate of gas in the dilute bed; The molar flow rate of each gas component at the inlet of the dilute phase bed is: in, represents the molar flow rate of each gas component at the outlet of the dense phase bed, It represents the molar flow rate of each gas component at the outlet of the charring tank.

7. The modeling method of a pre-coke tank regeneration system according to claim 1, characterized in that: The axial temperature distribution of the regeneration system includes the axial temperature distribution of the burnt tank, and the calculation formula is: Among them, m g Indicates the gas mass in the burnt tank, m cat Indicates the amount of catalyst stored in the burnt tank, C p,g Indicates the specific heat of the gas in the burnt tank, C p,cat Indicates the specific heat of the catalyst in the burnt tank, Q react Indicates the heat of reaction.

8. The modeling method of a pre-coke tank regeneration system according to claim 1, characterized in that: The catalyst carbon content is: in, Expressed as the coke content on the spent catalyst, F cat Expressed as the mass flow rate of catalyst to be generated.

9. A modeling device for a pre-burned coke tank regeneration system, the modeling device being used in the modeling method according to any one of claims 1 to 8, characterized in that: It includes a model building module and a processing module. The model building module is used to establish a charring reaction kinetic model, a charring tank steady-state model and a regenerator steady-state model. The processing module is used to calculate the temperature distribution of the regeneration system, the composition of the regenerated flue gas and the catalyst carbon content.

10. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores computer-readable instructions. When the computer-readable instructions are executed by the processor, the steps of the modeling method according to any one of claims 1 to 8 are executed.

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