A numerical simulation method for carbon filtration gas recovery scheme

Abstract

The present application relates to the technical field of oil reservoir and energy utilization, and relates to a numerical simulation method of carbon filtration gas recovery scheme, comprising: finding out the spatial distribution of target area aquifer and mixed gas reservoir, establishing a three-dimensional geological structure model of the target reservoir; obtaining relevant parameters; establishing a mathematical model of carbon filtration gas recovery simulation based on a reservoir numerical simulator; depicting the expression of the dissolution process of CO2 in formation water in the carbon filtration gas recovery simulation process based on Henry's law; depicting the calculation formula of the residual CO2 amount in the porous medium in the carbon filtration gas recovery simulation process based on the Land model; constructing a reactive migration model of CO2 and CH4 mixed gas in the target reservoir under actual formation temperature and pressure according to the three-dimensional geological model, the mathematical model, the expression, the calculation formula and the relevant parameters; based on the reactive migration model, comparing and analyzing the influence of different production well numbers, positions and pressure differences on the CO2 dissolution storage amount and the CH4 mass fraction in the production well, and screening out the scheme with the maximum CO2 dissolution storage amount and CH4 mass fraction in the production well.

Description

Technical Field

[0001] This invention relates to the field of reservoir and energy utilization technology, and more specifically, to a numerical simulation method for a carbon-filtering gas production scheme. Background Technology

[0002] The massive emission of greenhouse gases such as CO2 is a major cause of the greenhouse effect. Underground geological layers, with their large storage capacity and high airtightness, are suitable for carbon dioxide sequestration. Compared to oil reservoirs, natural gas reservoirs are characterized by a wide gas source and the mixing of various gas types. Typically, gas reservoirs contain a certain amount of uneconomical residual gases, such as N2, H2S, and CO2. CO2 is much more soluble in water than CH4, meaning that under the same conditions, CO2 is more likely to dissolve in saline water, while CH4 is more likely to be released from the water. Furthermore, supercritical CO2 can undergo a series of chemical reactions in the underground environment. By leveraging the differences in the transport properties of CO2 and CH4 in aquifers, carbon sequestration gas production schemes can increase the CH4 mass fraction in gas wells and achieve CO2 geological sequestration.

[0003] Existing technologies mostly focus on CO2 displacement of CH4 for enhanced gas production and the impact of impurity gases such as CH4 on the CO2 geological sequestration process, but lack the ability to utilize aquifers for carbon filtration gas production to increase the CH4 mass fraction in gas wells and achieve CO2 geological sequestration. Summary of the Invention

[0004] To overcome the problem in the prior art of not utilizing aquifers for carbon filtration gas production to increase the CH4 mass fraction of gas wells and achieve CO2 geological sequestration, this invention provides a numerical simulation method for carbon filtration gas production schemes.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a numerical simulation method for a carbon-filtering gas extraction scheme, the method comprising:

[0006] Based on borehole data, well logging data, seismic data and hydrogeological data of the target area, the main aquifers, mixed gas reservoirs and their spatial distribution in the target area were identified. The mixed gas reservoirs consist of CO2 and CH4.

[0007] Based on the obtained aquifer, mixed gas reservoir and the spatial distribution of the aquifer and the mixed gas reservoir, a three-dimensional geological structure model of the target reservoir is established. The three-dimensional geological model is used to reflect the geological structure, tectonic features and spatial distribution of lithological parameters of the target reservoir.

[0008] Capillary pressure curves and water-gas two-phase relative permeability curves of the target reservoir were obtained based on capillary pressure experiments and displacement experiments at the indoor core scale.

[0009] Indoor hydrochemical tests, XRD mineral analysis, and high-temperature and high-pressure reactor experiments were conducted to determine the hydrochemical composition data of formation water, the mineral composition data of core samples, and the reaction kinetic parameters of the CO2-water-rock interaction process in the target reservoir.

[0010] A mathematical model for carbon filtering and gas production simulation was established based on a reservoir numerical simulator;

[0011] An expression describing the dissolution process of CO2 in formation water during carbon extraction simulation based on Henry's law;

[0012] A calculation formula for residual CO2 in porous media during carbon filter gas extraction simulation based on the Land model;

[0013] Based on the established three-dimensional geological model, mathematical model, expressions, calculation formulas, and the obtained target reservoir geological structure, structural features, spatial distribution of lithological parameters, capillary pressure curves, relative permeability curves of water and gas phases, formation water hydrochemical composition data, core mineral composition data, and reaction kinetic parameters, a reactive migration model of CO2 and CH4 mixture in the target reservoir under actual formation temperature and pressure is constructed.

[0014] Based on this reactive migration model, by comparing and analyzing the effects of different numbers, locations, and pressure differences of production wells on the amount of CO2 dissolved and stored and the mass fraction of CH4 in production wells, the scheme with the largest amount of CO2 dissolved and stored and the mass fraction of CH4 in production wells was selected.

[0015] Preferably, the mathematical model includes a seepage equation, a phase equilibrium equation, a saturation equation, and a molar compatibility equation.

[0016] Preferably, for the water component and the components in the oil and gas phases, the finite difference scheme of the seepage equation is as follows:

[0017]

[0018] In the formula, the superscript n represents time n; the superscript n+1 represents time n+1; the subscript i represents component i; the subscript j represents phase j; the subscript o represents oil; the subscript g represents gas; the subscript w represents water; D is the depth (m); n c The total score is excluding water; N i The number of moles of component i in each grid, expressed in mol; P represents the number of moles of water component in each grid, in mol; p represents pressure, in Pa; P cog P is the capillary pressure of oil and gas, and its unit is Pa; cwo The pressure in the oil-water capillary tube is expressed in Pa; q i For the source and sink of oil and gas components, For the source and sink terms of the aqueous phase equation; t is time, in seconds; T j Let be the hydrodynamic coefficient of phase j, and its unit is m. 2 / s; V is the grid volume, with units of m. 3 ;y ij Let be the mole fraction of component i in phase j; γ be the gravity term; Δt be the time step, in seconds; in equations (1) and (2), it is assumed that there is no mass transfer between the aqueous phase and the oil and gas phases. If the superscript m is n, the grid is calculated explicitly; if it is n+1, it is calculated implicitly. i It is a function of molar density, saturation, and component content, and the calculation formula is as follows:

[0019] N i =φ(ρ o S o y io +ρ g S g y ig ), i = 1, ..., n c (3)

[0020]

[0021] In the formula, φ represents porosity; ρ j The molar density of phase j (m 3 / mol); S j Let be the saturation of phase j.

[0022] Preferably, based on the phase equilibrium equation, if the oil and gas system is located in a two-phase region, the number of moles N of component i in the gas phase is... ig and the number of moles N in the oil phase io This can be obtained by solving the following thermodynamic equilibrium equation:

[0023] lnf ig =lnf io i = 1, ..., n c (5)

[0024] N io =N i -N ig (6)

[0025] In the formula: f ig and f io , respectively, represent the fugacity of component i in the gas phase and oil phase, with units of Pa.

[0026] Preferably, the saturation is related to the total number of moles of substance in each phase:

[0027]

[0028] In the formula, S w S o S g These represent the saturation levels of the aqueous phase, oil phase, and gas phase, respectively, ρ. w , ρ o , ρ g These are the molar densities of the water, oil, and gas phases under formation conditions, respectively, in N. o and N g These represent the number of moles of oil and gas phases in each grid.

[0029] Preferably, the molar compatibility equation is based on N. i The definition yields the following equation:

[0030]

[0031] Equation (10) forces the number of moles of component i in each grid to be consistent with the molar density, saturation and porosity.

[0032] Preferably, the expression is

[0033]

[0034] In the formula, This represents the mole fraction of CO2 in the aqueous phase. P represents the fugacity of CO2 in the aqueous phase, expressed in kPa. ref This is a reference pressure, and its unit is kPa; The Henry's constant for CO2 at the reference pressure. This is the partial molar volume of CO2 at infinite dilution, and its unit is m³. 3 / mol; R is the universal gas constant; T is the temperature, in °C.

[0035] Preferably, the calculation formula is:

[0036]

[0037] In the formula, S gr S represents the residual CO2 saturation. gcrit S represents the critical gas saturation of CO2. g,max is the maximum CO2 gas saturation; C is the Land parameter calculated from the critical gas saturation.

[0038] Preferably, the three-dimensional geological structure model includes a depiction of the reservoir's geological structure, texture, boundaries, porosity, permeability, water saturation, and well pattern.

[0039] Preferably, the reaction kinetic parameters include the reaction rate constant, activation energy, and reaction specific surface area.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention establishes a model of the seepage process of CO2 and CH4 mixed gas under actual formation temperature and pressure conditions. By analyzing the influence of different production well numbers, different production well locations and different production well pressures on the carbon filtering and gas production capacity of the target reservoir, the present invention proposes the optimal carbon filtering and gas production scheme for the target reservoir. The present invention achieves CO2 geological sequestration while increasing the CH4 gas mass fraction in the gas production well. Detailed Implementation

[0041] Example 1

[0042] A numerical simulation method for a carbon-filtered gas extraction scheme, the method comprising:

[0043] Based on borehole data, well logging data, seismic data and hydrogeological data of the target area, the main aquifers, mixed gas reservoirs and spatial distribution of aquifers and mixed gas reservoirs in the target area were identified. The mixed gas reservoirs are CO2 and CH4.

[0044] Based on the obtained spatial distribution of aquifers, mixed gas reservoirs, and aquifers and mixed gas reservoirs, a three-dimensional geological structure model of the target reservoir is established. The three-dimensional geological model is used to reflect the spatial distribution of the geological structure, tectonic features, and lithological parameters of the target reservoir.

[0045] Capillary pressure curves and water-gas two-phase relative permeability curves of the target reservoir were obtained based on capillary pressure experiments and displacement experiments at the indoor core scale.

[0046] Indoor hydrochemical tests, XRD mineral analysis, and high-temperature and high-pressure reactor experiments were conducted to determine the hydrochemical composition data of formation water, the mineral composition data of core samples, and the reaction kinetic parameters of the CO2-water-rock interaction process in the target reservoir.

[0047] A mathematical model for carbon filtering and gas production simulation was established based on a reservoir numerical simulator;

[0048] An expression describing the dissolution process of CO2 in formation water during carbon extraction simulation based on Henry's law;

[0049] A calculation formula for residual CO2 in porous media during carbon filter gas extraction simulation based on the Land model;

[0050] Based on the established three-dimensional geological model, mathematical model, expressions, calculation formulas, and the obtained target reservoir geological structure, structural features, spatial distribution of lithological parameters, capillary pressure curves, relative permeability curves of water and gas phases, formation water hydrochemical composition data, core mineral composition data, and reaction kinetic parameters, a reactive migration model of CO2 and CH4 mixture in the target reservoir under actual formation temperature and pressure is constructed.

[0051] Based on this reactive migration model, by comparing and analyzing the effects of different numbers, locations, and pressure differences of production wells on the amount of CO2 dissolved and stored and the mass fraction of CH4 in production wells, the scheme with the largest amount of CO2 dissolved and stored and the mass fraction of CH4 in production wells was selected.

[0052] In this embodiment, the three-dimensional geological structure model includes the characterization of the reservoir's geological structure, texture, boundaries, porosity, permeability, water saturation, and well pattern.

[0053] In this embodiment, the reaction kinetic parameters include the reaction rate constant, activation energy, and reaction specific surface area.

[0054] Example 2

[0055] A numerical simulation method for a carbon-filtered gas extraction scheme, the method comprising:

[0056] Based on borehole data, well logging data, seismic data and hydrogeological data of the target area, the main aquifers, mixed gas reservoirs and spatial distribution of aquifers and mixed gas reservoirs in the target area were identified. The mixed gas reservoirs are CO2 and CH4.

[0057] Based on the obtained spatial distribution of aquifers, mixed gas reservoirs, and aquifers and mixed gas reservoirs, a three-dimensional geological structure model of the target reservoir is established. The three-dimensional geological model is used to reflect the spatial distribution of the geological structure, tectonic features, and lithological parameters of the target reservoir.

[0058] Capillary pressure curves and water-gas two-phase relative permeability curves of the target reservoir were obtained based on capillary pressure experiments and displacement experiments at the indoor core scale.

[0059] Indoor hydrochemical tests, XRD mineral analysis, and high-temperature and high-pressure reactor experiments were conducted to determine the hydrochemical composition data of formation water, the mineral composition data of core samples, and the reaction kinetic parameters of the CO2-water-rock interaction process in the target reservoir.

[0060] A mathematical model for carbon filtering and gas production simulation was established based on a reservoir numerical simulator. The mathematical model includes the seepage equation, phase equilibrium equation, saturation equation, and molar compatibility equation.

[0061] For the water component and the components in the oil and gas phases, the finite difference scheme of the seepage equation is as follows:

[0062]

[0063] In the formula, the superscript n represents time n; the superscript n+1 represents time n+1; the subscript i represents component i; the subscript j represents phase j; the subscript o represents oil; the subscript g represents gas; the subscript w represents water; D is the depth (m); n c The total score is excluding water; N iThe number of moles of component i in each grid, expressed in mol; P represents the number of moles of water component in each grid, in mol; p represents pressure, in Pa; P cog P is the capillary pressure of oil and gas, and its unit is Pa; cwo The capillary pressure of the oil and water is expressed in Pa; q represents the source and sink terms; t represents time, expressed in seconds; T j Let be the hydrodynamic coefficient of phase j, and its unit is m. 2 / s; V is the grid volume, with units of m. 3 ;y ij Let be the mole fraction of component i in phase j; γ be the gravity term; Δt be the time step, in seconds; in equations (1) and (2), it is assumed that there is no mass transfer between the aqueous phase and the oil and gas phases. If the superscript m is n, the grid is calculated explicitly; if it is n+1, it is calculated implicitly. i It is a function of molar density, saturation, and component content, and the calculation formula is as follows:

[0064] N i =φ(ρ o S o y io +ρ g S g y ig ), i = 1, ..., n c (3)

[0065]

[0066] In the formula, φ represents porosity; ρ j The molar density of phase j (m 3 / mol); S j Let be the saturation of phase j.

[0067] Furthermore, based on the phase equilibrium equation, if the oil and gas system is located in a two-phase region, the number of moles N of component i in the gas phase is... ig and the number of moles N in the oil phase io This can be obtained by solving the following thermodynamic equilibrium equation:

[0068] lnf ig =lnf io i = 1, ..., n c (5)

[0069] N io =N i -N ig (6)

[0070] In the formula: f ig Let be the fugacity of component i in phase j, and its unit is Pa.

[0071] The saturation degree is related to the total number of moles of substance in each phase:

[0072]

[0073] In the formula, S w S o S g These represent the saturation levels of the aqueous phase, oil phase, and gas phase, respectively, ρ. w , ρ o , ρ g These are the molar densities of the water, oil, and gas phases under formation conditions, respectively, in N. o and N g These represent the number of moles of oil and gas phases in each grid.

[0074] In this embodiment, the molar compatibility equation is based on N i The definition yields the following equation:

[0075]

[0076] Equation (10) forces the number of moles of component i in each grid to be consistent with the molar density, saturation and porosity.

[0077] An expression describing the dissolution process of CO2 in formation water during carbon extraction simulation based on Henry's law;

[0078] A calculation formula for residual CO2 in porous media during carbon filter gas extraction simulation based on the Land model;

[0079] Based on the established three-dimensional geological model, mathematical model, expressions, calculation formulas, and the obtained target reservoir geological structure, structural features, spatial distribution of lithological parameters, capillary pressure curves, relative permeability curves of water and gas phases, formation water hydrochemical composition data, core mineral composition data, and reaction kinetic parameters, a reactive migration model of CO2 and CH4 mixture in the target reservoir under actual formation temperature and pressure is constructed.

[0080] Based on this reactive migration model, by comparing and analyzing the effects of different numbers, locations, and pressure differences of production wells on the amount of CO2 dissolved and stored and the mass fraction of CH4 in production wells, the scheme with the largest amount of CO2 dissolved and stored and the mass fraction of CH4 in production wells was selected.

[0081] Example 3

[0082] A numerical simulation method for a carbon-filtered gas extraction scheme, the method comprising:

[0083] Based on borehole data, well logging data, seismic data and hydrogeological data of the target area, the main aquifers, mixed gas reservoirs and spatial distribution of aquifers and mixed gas reservoirs in the target area were identified. The mixed gas reservoirs are CO2 and CH4.

[0084] Based on the obtained spatial distribution of aquifers, mixed gas reservoirs, and aquifers and mixed gas reservoirs, a three-dimensional geological structure model of the target reservoir is established. The three-dimensional geological model is used to reflect the spatial distribution of the geological structure, tectonic features, and lithological parameters of the target reservoir.

[0085] Capillary pressure curves and water-gas two-phase relative permeability curves of the target reservoir were obtained based on capillary pressure experiments and displacement experiments at the indoor core scale.

[0086] Indoor hydrochemical tests, XRD mineral analysis, and high-temperature and high-pressure reactor experiments were conducted to determine the hydrochemical composition data of formation water, the mineral composition data of core samples, and the reaction kinetic parameters of the CO2-water-rock interaction process in the target reservoir.

[0087] A mathematical model for carbon filtering and gas production simulation was established based on a reservoir numerical simulator. The mathematical model includes the seepage equation, phase equilibrium equation, saturation equation, and molar compatibility equation.

[0088] For the water component and the components in the oil and gas phases, the finite difference scheme of the seepage equation is as follows:

[0089]

[0090] In the formula, the superscript n represents time n; the superscript n+1 represents time n+1; the subscript i represents component i; the subscript j represents phase j; the subscript o represents oil; the subscript g represents gas; the subscript w represents water; D is the depth (m); n c The total score is excluding water; N i The number of moles of component i in each grid, expressed in mol; P represents the number of moles of water component in each grid, in mol; p represents pressure, in Pa; P cog P is the capillary pressure of oil and gas, and its unit is Pa; cwo The pressure in the oil-water capillary tube is expressed in Pa; q i For the source and sink of oil and gas components, For the source and sink terms of the aqueous phase equation; t is time, in seconds; T j Let be the hydrodynamic coefficient of phase j, and its unit is m. 2 / s; V is the grid volume, with units of m. 3 ;y ij γ is the mole fraction of component i in phase j; γ is the gravity term; Δt is the time step, with units of seconds.

[0091] In equations (1) and (2), it is assumed that there is no mass transfer between the aqueous phase and the oil and gas phases. If the superscript m is n, the grid is calculated explicitly; if it is n+1, it is calculated implicitly. i It is a function of molar density, saturation, and component content, and the calculation formula is as follows:

[0092] N i =φ(ρ o S o y io +ρ g S g y ig ), i = 1, ..., n c (3)

[0093]

[0094] In the formula, φ represents porosity; ρ j The molar density of phase j (m 3 / mol); S j Let be the saturation of phase j.

[0095] Furthermore, based on the phase equilibrium equation, if the oil and gas system is located in a two-phase region, the number of moles N of component i in the gas phase is... ig and the number of moles N in the oil phase io This can be obtained by solving the following thermodynamic equilibrium equation:

[0096] lnf ig =lnf io i = 1, ..., n c (5)

[0097] N io =N i -N ig (6)

[0098] In the formula: f ig and f io , respectively, represent the fugacity of component i in the gas phase and oil phase, with units of Pa.

[0099] The saturation degree is related to the total number of moles of substance in each phase:

[0100]

[0101] In the formula, S w S o S g These represent the saturation levels of the aqueous phase, oil phase, and gas phase, respectively, ρ. w , ρ o , ρ g These are the molar densities of the water, oil, and gas phases under formation conditions, respectively, in N. o and Ng These represent the number of moles of oil and gas phases in each grid.

[0102] In this embodiment, the molar compatibility equation is based on N i The definition yields the following equation:

[0103]

[0104] Equation (10) forces the number of moles of component i in each grid to be consistent with the molar density, saturation and porosity.

[0105] The expression describing the CO2 dissolution process in formation water during carbon extraction simulation based on Henry's law is as follows:

[0106]

[0107] In the formula, This represents the mole fraction of CO2 in the aqueous phase. P represents the fugacity of CO2 in the aqueous phase, expressed in kPa. ref This is a reference pressure, and its unit is kPa; The Henry's constant for CO2 at the reference pressure. This is the partial molar volume of CO2 at infinite dilution, and its unit is m³. 3 / mol; R is the universal gas constant; T is the temperature, in °C.

[0108] The calculation formula for residual CO2 in porous media during carbon filter gas extraction simulation is based on the Land model. The calculation formula is as follows:

[0109]

[0110] In the formula, S gr S represents the residual CO2 gas saturation. gcrit S represents the critical gas saturation of CO2. g,max is the maximum CO2 gas saturation; C is the Land parameter calculated from the critical gas saturation.

[0111] Based on the established three-dimensional geological model, mathematical model, expressions, calculation formulas, and the obtained target reservoir geological structure, structural features, spatial distribution of lithological parameters, capillary pressure curves, relative permeability curves of water and gas phases, formation water hydrochemical composition data, core mineral composition data, and reaction kinetic parameters, a reactive migration model of CO2 and CH4 mixture in the target reservoir under actual formation temperature and pressure is constructed.

[0112] Based on this reactive migration model, by comparing and analyzing the effects of different numbers, locations, and pressure differences of production wells on the amount of CO2 dissolved and stored and the mass fraction of CH4 in production wells, the scheme with the largest amount of CO2 dissolved and stored and the mass fraction of CH4 in production wells was selected.

[0113] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A numerical simulation method for a carbon-filtered gas extraction scheme, characterized in that, The method includes: Based on borehole data, well logging data, seismic data and hydrogeological data of the target area, the main aquifers, mixed gas reservoirs and their spatial distribution in the target area were identified. The mixed gas reservoirs consist of CO2 and CH4. Based on the obtained aquifer, mixed gas reservoir and the spatial distribution of the aquifer and the mixed gas reservoir, a three-dimensional geological structure model of the target reservoir is established. The three-dimensional geological structure model is used to reflect the geological structure, tectonic features and spatial distribution of lithological parameters of the target reservoir. Capillary pressure curves and water-gas two-phase relative permeability curves of the target reservoir were obtained based on capillary pressure experiments and displacement experiments at the indoor core scale. Indoor hydrochemical tests, XRD mineral analysis, and high-temperature and high-pressure reactor experiments were conducted to determine the hydrochemical composition data of formation water, the mineral composition data of core samples, and the reaction kinetic parameters of the CO2-water-rock interaction process in the target reservoir. A mathematical model for carbon filtering and gas production simulation was established based on a reservoir numerical simulator; An expression describing the dissolution process of CO2 in formation water during carbon extraction simulation based on Henry's law; A calculation formula for residual CO2 in porous media during carbon filter gas extraction simulation based on the Land model; Based on the established three-dimensional geological structure model, mathematical model, expression, calculation formula, and the obtained target reservoir geological structure, structural features, spatial distribution of lithological parameters, capillary pressure curve, relative permeability curve of water-gas two phases, formation water hydrochemical composition data, core mineral composition data, and reaction kinetic parameters, a reactive migration model of CO2 and CH4 mixture in the target reservoir under actual formation temperature and pressure is constructed. Based on this reactive migration model, by comparing and analyzing the effects of different numbers, locations, and pressure differences of production wells on the amount of CO2 dissolved and stored and the mass fraction of CH4 in production wells, the scheme with the largest amount of CO2 dissolved and stored and the mass fraction of CH4 in production wells was selected.

2. The numerical simulation method for the carbon-filtered gas extraction scheme according to claim 1, characterized in that, The mathematical model includes the seepage equation, phase equilibrium equation, saturation equation, and molar compatibility equation.

3. The numerical simulation method for the carbon-filtered gas extraction scheme according to claim 2, characterized in that, For the water component and the components in the oil and gas phases, the finite difference scheme of the seepage equation is as follows: In the formula, the superscript n represents time n; the superscript n+1 represents time n+1; the subscript i represents component i; the subscript j represents phase j; the subscript o represents oil; the subscript g represents gas; the subscript w represents water; D is the depth (m); n c The total score is excluding water; N i The number of moles of component i in each grid, expressed in mol; P represents the number of moles of water component in each grid, in mol; p represents pressure, in Pa; P cog P is the capillary pressure of oil and gas, and its unit is Pa; cwo The pressure in the oil-water capillary tube is expressed in Pa; q i For the source and sink of oil and gas components, These are the source and sink terms in the aqueous phase equation; t represents time, and its unit is seconds (s). T j Let be the hydrodynamic coefficient of phase j, and its unit is m. 2 / s; V is the grid volume, with units of m. 3 ;y ij γ is the mole fraction of component i in phase j; γ is the gravity term; Δt is the time step, with units of seconds. In equations (1) and (2), it is assumed that there is no mass transfer between the aqueous phase and the oil and gas phases. If the superscript m is n, the grid is calculated explicitly; if it is n+1, it is calculated implicitly. i It is a function of molar density, saturation, and component content, and the calculation formula is as follows: N i =φ(ρ o S o y io +r g S g y ig ),i=1,…n c (3) In the formula, φ represents porosity; ρ j The molar density of phase j (m 3 / mol); s j Let be the saturation of phase j.

4. The numerical simulation method for the carbon-filtered gas extraction scheme according to claim 3, characterized in that, Based on the phase equilibrium equation, if the oil and gas system is located in the two-phase region, the number of moles N of component i in the gas phase is... ig and the number of moles N in the oil phase io This can be obtained by solving the following thermodynamic equilibrium equation: lnf ig =lnf io ,i=1,…n c (5) N io =N i -N ig (6) In the formula: f ig and f io , respectively, represent the fugacity of component i in the gas phase and oil phase, with units of Pa.

5. The numerical simulation method for the carbon-filtered gas extraction scheme according to claim 4, characterized in that, Saturation is related to the total number of moles of substance in each phase: In the formula, S w S o S g These represent the saturation levels of the aqueous, oil, and gas phases, respectively, ρ. w , ρ o , ρ g These are the molar densities of the water, oil, and gas phases under formation conditions, respectively, in N. o and N g These represent the number of moles of oil and gas phases in each grid.

6. The numerical simulation method for the carbon-filtered gas extraction scheme according to claim 5, characterized in that, The molar compatibility equation, based on N i The definition yields the following equation: Equation (10) forces the number of moles of component i in each grid to be consistent with the molar density, saturation and porosity.

7. The numerical simulation method for carbon-filtered gas extraction scheme according to any one of claims 1 to 6, characterized in that, The expression is In the formula, This represents the mole fraction of CO2 in the aqueous phase. P represents the fugacity of CO2 in the aqueous phase, expressed in kPa. ref This is a reference pressure, and its unit is kPa; The Henry's constant for CO2 at the reference pressure. This is the partial molar volume of CO2 at infinite dilution, and its unit is m³. 3 / mol; R is the universal gas constant; T is the temperature, in °C.

8. The numerical simulation method for carbon-filtered gas extraction scheme according to any one of claims 1 to 6, characterized in that, The calculation formula is as follows: In the formula, S gr S represents the residual CO2 saturation. gcrit S represents the critical gas saturation of CO2. g,max is the maximum CO2 gas saturation; C is the Land parameter calculated from the critical gas saturation.

9. The numerical simulation method for the carbon-filtered gas extraction scheme according to claim 1, characterized in that, The three-dimensional geological structure model includes a depiction of the reservoir's geological structure, texture, boundaries, porosity, permeability, water saturation, and well pattern.

10. The numerical simulation method for the carbon-filtered gas extraction scheme according to claim 1, characterized in that, The reaction kinetic parameters include the reaction rate constant, activation energy, and reaction specific surface area.

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