Compact reservoir CO2-WAG oil displacement and burying capacity calculation method, device and equipment

Abstract

The invention discloses a tight reservoir CO2-WAG oil displacement and burying capacity calculation method, device and equipment, and the method comprises the steps: constructing a first seepage control equation representing three-phase seepage control of a matrix system and a second seepage control equation representing three-phase seepage control of an artificial fracture system according to the law of mass conservation and momentum conservation; establishing a three-phase seepage auxiliary equation; and solving the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation based on the basic parameters of the tight reservoir of the target area, and calculating to obtain the productivity data of carbon dioxide-water vapor alternate driving carbon utilization and burying of the tight reservoir. According to the method, the influence of factors such as diffusion mass transfer, three-phase capillary pressure, three-phase relative permeability hysteresis and fluid channeling between fractures and matrixes on the CO2-WAG flooding seepage law of the tight reservoir is fully considered, and accurate and effective prediction and evaluation of the productivity and carbon dioxide burying potential of the tight reservoir in the target area can be achieved.

Description

Technical Field

[0001] The present application relates to the field of oil and gas development technology, and in particular to a method for preparing a dense reservoir CO 2 -WAG oil recovery and storage capacity calculation methods, devices and equipment. Background Art

[0002] Tight oil reservoirs are widely distributed, have huge reserves, and have mature mining technology, becoming an important part of oil and gas exploration and development. 2 ) has strong injection capacity and has the functions of swelling energy enhancement, mass transfer efficiency enhancement and miscible phase efficiency enhancement. For tight reservoirs, CO 2 It can enter nano-scale pores and effectively absorb and drive oil from the matrix, which can significantly increase crude oil production and reservoir recovery. However, due to the influence of fluidity difference, the injected CO 2 Viscous fingering is likely to occur, forming a gas channeling advantage channel, causing CO 2 Inefficient or ineffective injection. 2 -WAG) can inhibit gas channeling, improve the degree of production, and significantly increase the CO 2 Development effect.

[0003] CO 2 During the WAG injection process, the three-phase flow of oil, gas and water is complex. Gas diffusion, fractures, capillary pressure and phase permeability hysteresis effects will affect the three-phase flow characteristics, thereby affecting the tight reservoir development dynamics and carbon storage potential prediction. 2 -WAG carbon flooding utilization and storage seepage characterization model only considers the effects of phase change, gravity, capillary force and fractures, but the CO 2 -WAG flooding seepage law is affected by many factors. Considering only the effects of phase change, gravity, capillary force and fractures, it is impossible to achieve the goal of CO2 flooding in tight reservoirs. 2 - Accurate and reliable prediction of WAG carbon utilization and storage capacity.

[0004] For the above tight reservoir CO 2 - The accuracy and reliability of WAG carbon utilization and storage capacity calculations are low, and no effective solution has been found so far. Summary of the invention

[0005] The purpose of the embodiments of this specification is to provide a dense reservoir CO 2 -WAG oil recovery and storage capacity calculation method, device and equipment to solve the problem of CO 2 - Low accuracy and reliability of WAG carbon utilization and storage capacity calculations.

[0006] In order to solve the above technical problems, the present specification provides a first aspect of a tight reservoir CO 2 -WAG flooding and storage capacity calculation method, including:

[0007] According to the laws of conservation of mass and conservation of momentum, a first seepage control equation characterizing the three-phase seepage control of the matrix system and a second seepage control equation characterizing the three-phase seepage control of the artificial fracture system are constructed;

[0008] Establishing a three-phase seepage auxiliary equation, wherein the three-phase seepage auxiliary equation includes a saturation equation, a rock state equation, a capillary pressure equation considering phase permeability hysteresis and a three-phase phase permeability equation, a gas diffusion equation, and a cross-flow equation between the matrix and the artificial fracture;

[0009] The first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation are solved based on the basic parameters of the tight reservoir in the target area to calculate the CO 2 -WAG oil recovery and storage capacity data.

[0010] In some embodiments of the present specification, the first seepage control equation is expressed by the following formula:

[0011]

[0012] Among them, ▽ represents the Hamiltonian operator; ρ o , g and ρ w Respectively represent the density of oil phase, gas phase and water phase; K m represents the matrix permeability; Respectively represent the relative permeability of oil phase, gas phase and water phase in the three-phase relative permeability; μ o , μ g and μ w Respectively represent the viscosity of oil phase, gas phase and water phase; B o , B g and B w represent the oil phase volume coefficient, gas phase volume coefficient and water phase volume coefficient respectively;

[0013] P m represents the matrix pressure; G o , G g and G w They represent the oil phase starting pressure gradient, gas phase starting pressure gradient and water phase starting pressure gradient respectively; q o ,q g and q w They represent the oil phase injection rate or production rate, gas phase injection rate or production rate, and water phase injection rate or production rate respectively; qomf ,q gmf and q wmf They represent the oil phase cross-flow rate, gas phase cross-flow rate and water phase cross-flow rate between fractures and matrix respectively; represents the matrix porosity; S om , S gm and S wm Respectively represent the oil saturation, gas saturation and water saturation in the matrix; F om represents the diffusion flux of carbon dioxide into crude oil;

[0014] The second seepage control equation is expressed by the following formula:

[0015]

[0016] Among them, K f represents the permeability of artificial fractures; P f Indicates the artificial fracture pressure; Indicates the porosity of artificial fractures; S of , S gf and S wf They represent the oil saturation, gas saturation and water saturation in the artificial fractures respectively.

[0017] In some embodiments of the present specification, the rock state equation is expressed by the following formula:

[0018]

[0019] in, and represent matrix porosity and artificial fracture porosity, respectively; and represent the matrix porosity and artificial fracture porosity under atmospheric pressure respectively; C m and C f represent the rock compression coefficients of the matrix system and artificial fracture system respectively; P m and P f represent the matrix pressure and artificial fracture pressure respectively, P a Indicates atmospheric pressure;

[0020] The saturation equation is expressed by the following formula:

[0021] S o +S g +S w =1;

[0022] Among them, S o , S g and S w They represent oil saturation, gas saturation and water saturation respectively.

[0023] In some embodiments of the present specification, the capillary pressure equation is expressed by the following formula:

[0024]

[0025] Among them, P cow Indicates the capillary pressure of oil and water phases; P cog Represents the capillary pressure of oil and gas phases; σ ow represents the interfacial tension between oil and water phases; σ og represents the interfacial tension between oil and gas phases; θ ow represents the contact angle between oil and water phases; θ og Represents the contact angle between oil and gas phases; φ m represents the matrix porosity; K m represents the matrix permeability; c o 、c w and c g Respectively represent the capillary entry pressure of oil phase, water phase and gas phase; a o 、a w and a g They represent the capillary number of oil phase, water phase and gas phase, respectively; S o , S w and S g Respectively represent oil saturation, water saturation and gas saturation; S or , S wr and S gr They represent residual oil saturation, irreducible water saturation and residual gas saturation respectively.

[0026] In some embodiments of the present specification, the three-phase permeability equation is expressed by the following formula:

[0027]

[0028] in, and Respectively represent the relative permeability of the oil phase, the relative permeability of the gas phase and the relative permeability of the water phase in the three-phase relative permeability; S' o , S' w and S' g represent the normalized oil saturation, normalized water saturation and normalized gas saturation respectively; K row Represents the relative permeability of the oil phase in the oil-water phase; K rwg Represents the relative permeability of water phase in gas-water phase; K rog Represents the relative permeability of the oil phase in the oil and gas phases; K rgw Indicates the relative permeability of gas phase in oil and gas phases; K rwoRepresents the relative permeability of water phase in oil-water phase; K rgo It represents the relative permeability of gas phase in oil and gas phase.

[0029] In some embodiments of the present specification, the cross-flow equation is expressed by the following formula:

[0030]

[0031] Among them, q omf ,q gmf and q wmf represents the oil phase cross-flow, gas phase cross-flow and water phase cross-flow between fractures and matrix respectively; σ represents the shape factor of the contact area between artificial fractures and matrix per unit volume of rock; K m represents the matrix permeability; and Respectively represent the relative permeability of oil phase, gas phase and water phase in the three-phase relative permeability; μ o , μ g and μ w Respectively represent the viscosity of oil phase, gas phase and water phase; B om , B gm and B wm represent the volume coefficient of oil phase, gas phase and water phase in the matrix respectively; P om , P gm and P wm Respectively represent the oil phase pressure, gas phase pressure and water phase pressure in the matrix; P of , P gf and P wf They represent the oil phase pressure, gas phase pressure and water phase pressure in the artificial fractures respectively.

[0032] In some embodiments of the present specification, the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation are solved based on the basic parameters of the tight reservoir in the target area to calculate the CO 2 -WAG flooding and storage capacity data, including:

[0033] Determining initial conditions and boundary conditions for calculation based on basic parameters of the tight reservoir in the target area;

[0034] Decomposing the first seepage control equation and the second seepage control equation into a pressure equation and a saturation equation based on the three-phase seepage auxiliary equation;

[0035] Based on the initial conditions and the boundary conditions, the implicit pressure-explicit saturation method is used to solve the pressure equation and the saturation equation to obtain the production capacity data.

[0036] In some embodiments of the present specification, after establishing the three-phase seepage auxiliary equation, the method further includes:

[0037] Based on the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation, the seepage process of the tight reservoir in the target area is simulated by adjusting engineering parameters to obtain simulation data;

[0038] Based on the simulation data, the change relationship between each parameter in the engineering parameters and the production capacity data is determined, and each parameter is optimized based on the determined change relationship.

[0039] The second aspect of this specification provides a dense reservoir CO 2 -WAG oil recovery and storage capacity calculation device, including:

[0040] A first building module is used to construct a first seepage control equation characterizing the three-phase seepage control of the matrix system and a second seepage control equation characterizing the three-phase seepage control of the artificial fracture system according to the laws of conservation of mass and conservation of momentum;

[0041] The second establishment module is used to establish a three-phase seepage auxiliary equation, which includes a saturation equation, a rock state equation, a capillary pressure equation considering phase permeability hysteresis and a three-phase phase permeability equation, a gas diffusion equation, and a crossflow equation between the matrix and the artificial fracture;

[0042] The production capacity calculation module is used to solve the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation based on the basic parameters of the tight reservoir in the target area, and calculate the CO 2 -WAG flooding and storage capacity data.

[0043] The third aspect of this specification provides an electronic device, comprising: a memory and a processor, the processor and the memory are communicatively connected to each other, the memory stores computer instructions, and the processor implements the steps of the method described in the first aspect by executing the computer instructions.

[0044] The tight reservoir CO provided in the examples of this specification 2-WAG oil displacement and storage capacity calculation method, device and equipment, by constructing the first seepage control equation characterizing the three-phase seepage control of the matrix system and the second seepage control equation characterizing the three-phase seepage control of the artificial fracture system according to the law of conservation of mass and momentum; establishing the three-phase seepage auxiliary equation, which includes the saturation equation, the rock state equation, the capillary pressure equation considering the phase permeability hysteresis and the three-phase phase permeability equation, the gas diffusion equation and the cross-flow equation between the matrix and the artificial fracture; solving the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation based on the basic parameters of the tight reservoir in the target area, and calculating the capacity data of carbon dioxide-water gas alternating carbon displacement and storage in the tight reservoir. Through the above method, the factors such as diffusion mass transfer, three-phase capillary pressure, three-phase phase permeability hysteresis and cross-flow between fractures and matrix are fully considered to affect the CO2 in tight oil reservoirs. 2 -WAG flooding seepage law, the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation are constructed. Based on the constructed equations, the production capacity and carbon dioxide storage potential of the tight reservoir in the target area can be accurately and effectively predicted and evaluated, and a basis can be provided for the optimization of engineering parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some implementation methods recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0046] Figure 1 The dense reservoir CO provided in the embodiment of this specification is shown. 2 - A schematic diagram of the WAG flooding and storage capacity calculation method;

[0047] Figure 2 It is a schematic diagram of a method for calculating production capacity data provided in an embodiment of this specification;

[0048] Figure 3 It is a schematic diagram showing the variation curve of cumulative oil production over time at different injection rates provided in the embodiments of this specification;

[0049] Figure 4 It is a schematic diagram showing the curve of the change of gas-oil ratio over time at different injection speeds provided in the embodiment of this specification;

[0050] Figure 5 It is a schematic diagram showing the variation curve of the cumulative oil production over time under different injection cycles provided in the embodiment of this specification;

[0051] Figure 6 It is a schematic diagram showing the variation curve of gas-oil ratio over time under different injection cycles provided in the embodiment of this specification;

[0052] Figure 7 It is a schematic diagram showing the variation curve of the cumulative oil production over time under different gas-water ratios provided in the embodiments of this specification;

[0053] Figure 8 It is a schematic diagram showing the curve of the change of gas-oil ratio over time under different gas-water ratios provided in the embodiment of this specification;

[0054] Fig. 9 The dense reservoir CO provided in the embodiment of this specification is shown. 2 - A schematic diagram of the WAG oil recovery and storage capacity calculation device;

[0055] Fig.10 Shown is a schematic diagram of an electronic device provided in an embodiment of this specification. DETAILED DESCRIPTION

[0056] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0057] As mentioned above, CO 2 During the WAG injection process, the three-phase flow of oil, gas and water is complex. Gas diffusion, fractures, capillary pressure and phase permeability hysteresis effects will affect the three-phase flow characteristics, thereby affecting the tight reservoir development dynamics and carbon storage potential prediction. 2 The WAG carbon flooding utilization and storage seepage characterization model only considers the effects of phase change, gravity, capillary force and fractures, and cannot realize the CO2 characterization of tight reservoirs. 2 - Accurate and reliable prediction of WAG carbon utilization and storage capacity.

[0058] In this application, through the study of the three-phase seepage law, it is found that diffusion mass transfer, three-phase capillary pressure and three-phase phase permeability hysteresis also affect the CO 2 Therefore, in order to solve the problem of low accuracy and reliability of the above-mentioned capacity calculation, a method for calculating the capacity of a tight reservoir CO2 is provided in the embodiments of this specification. 2-WAG flooding and storage capacity calculation method, device and equipment, fully consider the diffusion mass transfer, three-phase capillary pressure, three-phase permeability hysteresis and cross-flow between fractures and matrix and other factors on the tight oil reservoir CO 2 -WAG flooding seepage law, the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation are constructed. Among them, the three-phase seepage auxiliary equation can include the saturation equation, the rock state equation, the capillary pressure equation considering the phase permeability hysteresis and the three-phase phase permeability equation, the gas diffusion equation and the cross-flow equation between the matrix and the artificial fracture. Based on the constructed equations and the basic parameters of the tight reservoirs in the target area, the production capacity and carbon dioxide storage potential of the tight reservoirs in the target area can be accurately and effectively predicted and evaluated, and a basis can be provided for the optimization of engineering parameters.

[0059] In the method provided in the embodiment of the present application, the execution subject of each step may be an electronic device, which refers to an electronic device with data calculation, processing and storage capabilities. The electronic device may be a terminal such as a personal computer (PC), a tablet computer, a smart phone, a wearable device, an intelligent robot, etc.; or it may be a server. Among them, the server may be an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides cloud computing services.

[0060] The following first describes the tight reservoir CO2 removal method provided by the embodiment of the present application in conjunction with the accompanying drawings. 2 -WAG oil recovery and storage capacity calculation method is introduced.

[0061] Figure 1 The dense reservoir CO provided in the embodiment of this specification is shown. 2 -A schematic diagram of the WAG oil recovery and storage capacity calculation method. Although this specification provides method operation steps or device structures as shown in the following embodiments or drawings, the method or device may include more or fewer operation steps or module units after partial merger based on routine or no creative labor. In the steps or structures where there is no necessary causal relationship logically, the execution order of these steps or the module structure of the device is not limited to the execution order or module structure shown in the embodiments or drawings of this specification. When the method or module structure is applied in actual devices, servers or terminal products, it can be executed sequentially or in parallel according to the method or module structure shown in the embodiments or drawings (for example, in a parallel processor or multi-threaded processing environment, or even in a distributed processing or server cluster implementation environment). As Figure 1 As shown, the method may include:

[0062] S101: According to the laws of conservation of mass and conservation of momentum, a first seepage control equation characterizing the three-phase seepage control of the matrix system and a second seepage control equation characterizing the three-phase seepage control of the artificial fracture system are constructed.

[0063] It can be understood that when constructing the first seepage control equation and the second seepage control equation, based on the tight reservoir CO 2 -WAG flooding injection characteristics are established. The three phases may include oil phase, gas phase and water phase. Specifically, in the process of constructing the first seepage control equation and the second seepage control equation, CO 2 Factors such as diffusion mass transfer, cracks, three-phase capillary pressure, three-phase permeability hysteresis and crossflow between cracks and matrix are constructed through differential method based on the law of conservation of mass and momentum.

[0064] In some embodiments of the present specification, the first seepage control equation can be expressed by the following formula:

[0065]

[0066] Among them, ▽ can represent the Hamiltonian operator; ρ o , g and ρ w can represent the density of oil phase, gas phase and water phase respectively, 10 3 kg / m 3 ; K m It can be expressed as matrix permeability, mD; and It can represent the relative permeability of oil phase, gas phase and water phase in the three-phase relative permeability, mD; μ o , μ g and μ w It can represent the viscosity of oil phase, gas phase and water phase respectively, mPa·s; B o , B g and B w It can represent the oil phase volume coefficient, gas phase volume coefficient and water phase volume coefficient respectively, m 3 / m 3 ;P m Can express matrix pressure, MPa; G o , G g and G w It can represent the oil phase starting pressure gradient, gas phase starting pressure gradient and water phase starting pressure gradient, MPa / m; q o ,q g and q w It can represent the oil phase injection rate or production rate, gas phase injection rate or production rate, and water phase injection rate or production rate, m 3 / s;q omf ,q gmf and q wmf It can represent the oil phase cross-flow rate, gas phase cross-flow rate and water phase cross-flow rate between fracture and matrix respectively, m 3 / s; It can be used to express the matrix porosity, %; S om , S gm and S wm It can represent the oil saturation, gas saturation and water saturation in the matrix, %; F om It can be used to express the diffusion flux of carbon dioxide into crude oil, kg / (m 2 ·s).

[0067] In some embodiments of the present specification, the second seepage control equation can be expressed by the following formula:

[0068]

[0069] Among them, K f Can express the permeability of artificial fractures, mD; P f It can express the artificial fracture pressure, MPa; Can express artificial fracture porosity, %; S of , S gf and S wf It can represent the oil saturation, gas saturation and water saturation in artificial fractures respectively, %.

[0070] S102: Establishing a three-phase seepage auxiliary equation, wherein the three-phase seepage auxiliary equation includes a saturation equation, a rock state equation, a capillary pressure equation considering phase permeability hysteresis and a three-phase phase permeability equation, a gas diffusion equation, and a crossflow equation between the matrix and the artificial fracture.

[0071] It can be understood that the three-phase seepage auxiliary equation is a dual-medium three-phase seepage auxiliary equation for carbon utilization and burial of carbon dioxide-water gas alternating flooding in tight reservoirs. The three-phase capillary pressure and three-phase relative permeability are affected by phase permeability hysteresis, so the capillary pressure equation and three-phase phase permeability equation considering phase permeability hysteresis are constructed. Based on this, more accurate and reliable three-phase capillary pressure and three-phase relative permeability can be calculated, providing a basis for the accurate calculation of subsequent production data.

[0072] In some embodiments of the present specification, the saturation equation may be expressed by the following formula:

[0073] S o +S g +S w =1 Formula (3)

[0074] Among them, S o , Sg and S w It can represent oil saturation, gas saturation and water saturation respectively, in %.

[0075] In some embodiments of the present specification, the rock state equation can be expressed by the following formula:

[0076]

[0077] in, and can represent matrix porosity and artificial fracture porosity, % respectively; and It can represent the matrix porosity and artificial fracture porosity under atmospheric pressure, %; C m and C f can represent the rock compression coefficient of the matrix system and the artificial fracture system, 10 -4 / MPa -1 ;P m and P f It can represent the matrix pressure and artificial fracture pressure, MPa, P a Indicates atmospheric pressure, Pa.

[0078] In some embodiments of the present specification, the capillary pressure equation may be expressed by the following formula:

[0079]

[0080] Among them, P cow It can express the capillary pressure of oil and water phase, Pa; P cog It can express the capillary pressure of oil and gas phases, Pa; σ ow It can be used to express the interfacial tension between oil and water phases, Pa; σ og It can express the interfacial tension between oil and gas, Pa; θ ow It can be expressed as the contact angle between oil and water phases, degrees; θ og It can express the contact angle between oil and gas phases, degree; φ m Can be used to express matrix porosity, %; K m It can be expressed as matrix permeability, mD; c o 、c w and c g It can represent the oil phase capillary entry pressure, water phase capillary entry pressure and gas phase capillary entry pressure, Pa; a o 、a w and a g It can represent the oil phase capillary number, water phase capillary number and gas phase capillary number respectively; S o , S w and S gIt can represent oil saturation, water saturation and gas saturation respectively, %; S or , S wr and S gr It can represent residual oil saturation, irreducible water saturation and residual gas saturation respectively, %.

[0081] In some embodiments of the present specification, the three-phase permeability equation can be expressed by the following formula:

[0082]

[0083] in, and It can represent the relative permeability of oil phase, gas phase and water phase in the three-phase relative permeability respectively; S' o , S' w and S' g It can represent the normalized oil saturation, normalized water saturation and normalized gas saturation respectively; K row It can express the relative permeability of the oil phase in the oil-water phase; K rwg It can express the relative permeability of water phase in gas-water phase; K rog It can express the relative permeability of the oil phase in the oil and gas phases; K rgw It can express the relative permeability of gas phase in oil and gas phases; K rwo It can express the relative permeability of water phase in oil-water phase; K rgo It can express the relative permeability of gas phase in oil and gas phase.

[0084] In some embodiments of the present specification, the gas diffusion equation may be expressed by the following formula:

[0085]

[0086] Among them, F om and F of can represent the diffusion flux of carbon dioxide from the matrix and artificial fractures into the crude oil respectively; D can represent the carbon dioxide diffusion coefficient, m 2 / s; M can represent the molar mass of carbon dioxide, kg / mol; C om and C of They can represent the molar concentration of carbon dioxide in crude oil in the matrix and artificial fractures, mol / L respectively.

[0087] In some embodiments of the present specification, the crossflow equation can be expressed by the following formula:

[0088]

[0089] Among them, q omf,q gmf and q wmf It can represent the oil phase cross-flow rate, gas phase cross-flow rate and water phase cross-flow rate between fracture and matrix respectively, m 3 / s; σ can represent the shape factor of the contact area between artificial fractures and matrix in unit volume of rock; K m It can represent the matrix permeability; and It can represent the relative permeability of oil phase, gas phase and water phase in the three-phase relative permeability, mD; μ o , μ g and μ w It can represent the viscosity of oil phase, gas phase and water phase respectively, mPa·s; B om , B gm and B wm It can represent the volume coefficient of oil phase, gas phase and water phase in the matrix, m 3 / m 3 ;P om , P gm and P wm It can represent the oil phase pressure, gas phase pressure and water phase pressure in the matrix, Pa; P of , P gf and P wf They can represent the oil phase pressure, gas phase pressure and water phase pressure in the artificial fracture, Pa respectively.

[0090] S103: Solving the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation based on the basic parameters of the tight reservoir in the target area, and calculating the CO 2 -WAG oil recovery and storage capacity data.

[0091] It is understood that the productivity data may include data related to tight reservoir CO 2 - Data related to production capacity of WAG carbon flooding, utilization and storage. For example, it may include data corresponding to parameters such as daily oil production, daily gas production, recovery factor, pressure, saturation, etc.

[0092] Specifically, when solving the equations, the three-phase seepage auxiliary equations including formula (3) to formula (8) can be substituted into the seepage control equations of formula (1) and formula (2), and then the initial conditions and boundary conditions for solving the equations are constructed based on the basic parameters of the tight reservoir in the target area, and formula (1) and formula (2) substituted into formula (3) to formula (8) are solved to obtain the production capacity data.

[0093] In some embodiments of the present specification, the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation are solved based on the basic parameters of the tight reservoir in the target area to calculate the CO 2 -WAG oil recovery and storage capacity data may include: determining the initial conditions and boundary conditions of the calculation based on the basic parameters of the tight reservoir in the target area; decomposing the first seepage control equation and the second seepage control equation into a pressure equation and a saturation equation based on the three-phase seepage auxiliary equation; based on the initial conditions and the boundary conditions, using the implicit pressure and explicit saturation (IMPES) method to solve the pressure equation and the saturation equation to obtain the capacity data.

[0094] It can be understood that when calculating the production capacity, the implicit pressure-explicit saturation IMPES method can be used to calculate the CO 2 -WAG carbon flooding utilization and storage seepage control equations are solved to obtain parameters such as daily oil production, daily gas production, recovery factor, pressure and saturation, and compared with experimental simulation results to verify the accuracy of the model. Figure 2 As shown, the method may specifically include the following steps:

[0095] S1. Calculate the initial and boundary conditions of the given model.

[0096] Among them, the initial condition can be understood as the distribution characteristics of all variables in the reservoir at any time, which can be set based on the basic parameters of the reservoir. Under the initial condition, the reservoir pressure is the original formation pressure. In addition, under the initial condition, there are only oil phase and water phase in the matrix system and the artificial fracture system, and no gas phase. Specifically, the initial condition can be expressed by the following formula:

[0097]

[0098] Among them, P can represent the formation pressure, P i can represent the original formation pressure, C can represent the concentration of carbon dioxide at the initial diffusion moment in the reservoir not affected by water flooding; S o Can represent oil saturation, S oi It can represent the original oil saturation, S w Can be used to represent water saturation, S wi It can be expressed as the initial water saturation, S g It can indicate gas saturation.

[0099] Assuming that the reservoir boundary is a closed boundary with no external supply, there is no flow at the boundary. Furthermore, the boundary condition can be expressed by the following formula:

[0100]

[0101] S2. Use the implicit pressure explicit saturation method to solve the seepage control equation.

[0102] In the process of solving the coupled control equations, the coupled control equations can be decomposed into pressure equations and saturation equations by cutting off the connection between saturation and pressure in the control equations. Subsequently, the coupled equations can be solved by implicit pressure and explicit saturation.

[0103] Specifically, the capacity data can be calculated based on the initial conditions and boundary conditions, and the following parameters can be adjusted based on the changes in the calculation results over time: three-phase relative permeability Capillary pressure (P cow and P cog ), the diffusion flux of carbon dioxide into crude oil (F om 、F of ) and the cross-flow rate of each phase between the fracture and the matrix (q omf ,q gmf and q wmf ). Further, the IMPES model is run based on the adjusted parameters to obtain the production capacity data for each time period (e.g., Δt, 2Δt, ..., nΔt, etc.). The production capacity data may include oil phase, gas phase and water phase saturation, matrix and artificial fracture pressure, gas production, crude oil recovery factor, gas-oil ratio, etc. The calculated production capacity data is compared with the experimental simulation production capacity data to determine whether the constructed IMPES model is accurate. If it is inaccurate, the parameters are readjusted and the production capacity calculation is performed again. If it is accurate, it is determined whether the alternating slug is completed. If the alternating slug is completed, the calculation is stopped to obtain the final required production capacity data, otherwise the parameters are readjusted and the production capacity calculation is performed again.

[0104] In the embodiments of this specification, by decomposing the equation group into pressure equations and saturation equations, the IMPES method is used to solve the production capacity data such as oil, gas and water saturation, fracture and matrix pressure, gas production, crude oil recovery factor and gas-oil ratio.

[0105] In some embodiments of the present specification, after establishing the three-phase seepage auxiliary equation, it may also include: based on the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation, simulating the seepage process of the tight reservoir in the target area by adjusting the engineering parameters to obtain simulation data; determining the change relationship between each parameter in the engineering parameters and the production capacity data based on the simulation data, and optimizing each parameter based on the determined change relationship.

[0106] It can be understood that by considering the CO 2Diffusion mass transfer, fractures, three-phase capillary pressure, three-phase permeability hysteresis and cross-flow between fractures and matrix in tight reservoir CO 2 -WAG carbon flooding utilization and storage seepage control model can be used to determine the CO 2 - Water-gas alternating flooding development to optimize the production system. The optimized engineering parameters may include: injection rate, injection cycle and gas-water ratio.

[0107] The optimization process of the above-mentioned engineering parameters will be further introduced below in combination with specific embodiments with reference to the accompanying drawings.

[0108] In some embodiments of this specification, 4 injection rate schemes are designed for injection rate, namely: 9m3 / d, 12m3 / d, 15m3 / d, 18m3 / d, the simulation time is set to 10 years, the simulation time interval is days, and the simulation results of each scheme are as follows: Figure 3 and Figure 4 As shown. Figure 3 The cumulative oil production curves at different injection rates over time are shown. Figure 4 The curves of gas-oil ratio changing with time at different injection rates are shown. Figure 3 to Figure 4 It can be seen that as the injection rate increases, the cumulative oil production increases and the gas-oil ratio also increases. 3 / d, the cumulative oil production increased at a low rate, indicating that the impact of injection rate on cumulative oil production was reduced. Therefore, the injection rate can be reasonably set to 12m 3 / d.

[0109] In some embodiments of this specification, 4 injection cycle schemes are designed for the injection cycle, namely: 1 month, 2 months, 3 months, and 4 months. The simulation time is set to 10 years, and the simulation time interval is days. The simulation results of each scheme are as follows: Figure 5 to Figure 6 As shown. Figure 5 The cumulative oil production curves with time under different injection cycles are shown. Figure 6 The curves showing the change of gas-oil ratio over time under different injection cycles are shown. Figure 5 to Figure 6 It can be seen that as the injection cycle increases, the gas-oil ratio increases, while the cumulative oil production is negatively correlated. When the injection cycle exceeds 1 month, the cumulative oil production increases at a lower rate as the injection cycle increases, indicating that the impact of the injection cycle on the cumulative oil production decreases. The shorter the injection cycle, the better the injection effect. However, considering the actual situation on site, in order to facilitate production operations, the injection cycle can be reasonably set to 1 month.

[0110] In some embodiments of this specification, five schemes are designed for the gas-water ratio, which are: 0.6:1, 0.8:1, 1:1, 1.2:1, 1.46:1, the simulation time is set to 10 years, the simulation time interval is days, and the simulation results of each scheme are as follows: Figure 7 and Figure 8 As shown. Figure 7 The cumulative oil production curves at different gas-water ratios over time are shown. Figure 8 The curves of gas-oil ratio changing with time under different gas-water ratios are shown. Figures 7 and 8 It can be seen that as the gas-water ratio increases, the cumulative oil production and gas-oil ratio increase. When the gas-water ratio exceeds 0.8:1, the cumulative oil production does not increase significantly as the gas-water ratio increases, indicating that when the gas-water ratio exceeds 0.8:1, the gas-water ratio has no significant effect on the cumulative oil production. Therefore, the gas-water ratio can be reasonably set to 0.8:1.

[0111] Based on the above-mentioned tight reservoir CO 2 -WAG oil recovery and storage capacity calculation method, one or more embodiments of this specification also provide a tight reservoir CO 2 -WAG oil recovery and storage capacity calculation device. The device may include a device (including a distributed system), software (application), module, plug-in, server, client, etc. that uses the method described in the embodiments of this specification and is combined with the necessary implementation hardware. Based on the same innovative concept, the device in one or more embodiments provided in the embodiments of this specification is as described in the following embodiments. Since the implementation scheme and method of the device to solve the problem are similar, the implementation of the specific device in the embodiments of this specification can refer to the implementation of the aforementioned method, and the repetitions will not be repeated. As used below, the term "unit" or "module" can be a combination of software and / or hardware that implements predetermined functions. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceived. Fig. 9 The dense reservoir CO provided in the embodiment of the present application is shown. 2 - A schematic diagram of the WAG oil recovery and storage capacity calculation device. Fig. 9 As shown, the tight reservoir CO 2 -WAG oil recovery and storage capacity calculation device 900 may include:

[0112] The first building module 901 is used to construct a first seepage control equation characterizing the three-phase seepage control of the matrix system and a second seepage control equation characterizing the three-phase seepage control of the artificial fracture system according to the laws of conservation of mass and conservation of momentum.

[0113] The second establishment module 902 is used to establish the three-phase seepage auxiliary equation, which includes the saturation equation, the rock state equation, the capillary pressure equation considering the phase permeability hysteresis and the three-phase phase permeability equation, the gas diffusion equation and the crossflow equation between the matrix and the artificial fracture.

[0114] The production capacity calculation module 903 is used to solve the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation based on the basic parameters of the tight reservoir in the target area, and calculate the CO 2 -WAG oil recovery and storage capacity data.

[0115] In some embodiments of the present specification, the first seepage control equation established by the first establishing module 901 can be expressed by the following formula:

[0116]

[0117] Among them, ▽ can represent the Hamiltonian operator; ρ o , g and ρ w Can represent the density of oil phase, gas phase and water phase respectively; K m It can represent the matrix permeability; and It can represent the relative permeability of oil phase, gas phase and water phase in the three-phase relative permeability respectively; μ o , μ g and μ w It can represent the viscosity of oil phase, gas phase and water phase respectively; B o , B g and B w They can represent the oil phase volume coefficient, gas phase volume coefficient and water phase volume coefficient respectively;

[0118] P m Can represent matrix pressure; G o , G g and G w It can represent the oil phase starting pressure gradient, gas phase starting pressure gradient and water phase starting pressure gradient respectively; q o ,q g and q w It can represent the oil phase injection rate or production rate, gas phase injection rate or production rate, and water phase injection rate or production rate respectively; q omf ,q gmf and q wmf It can represent the oil phase cross-flow rate, gas phase cross-flow rate and water phase cross-flow rate between fracture and matrix respectively; It can represent the matrix porosity; S om , Sgm and S wm It can represent the oil saturation, gas saturation and water saturation in the matrix respectively; F om It can represent the diffusion flux of carbon dioxide into crude oil;

[0119] The second seepage control equation established by the first establishment module 901 can be expressed by the following formula:

[0120]

[0121] Among them, K f Can represent the permeability of artificial fractures; P f It can indicate the pressure of artificial fractures; Can represent the porosity of artificial fractures; S of , S gf and S wf It can represent the oil saturation, gas saturation and water saturation in artificial fractures respectively.

[0122] In some embodiments of the present specification, the rock state equation established by the second establishment module 902 can be expressed by the following formula:

[0123]

[0124] in, and They can represent matrix porosity and artificial fracture porosity respectively; and They can represent the matrix porosity and artificial fracture porosity under atmospheric pressure respectively; C m and C f can represent the rock compression coefficient of the matrix system and the artificial fracture system respectively; P m and P f can represent the matrix pressure and artificial fracture pressure respectively, P a Indicates atmospheric pressure;

[0125] The saturation equation established by the second establishment module 902 can be expressed by the following formula:

[0126] S o +S g +S w =1;

[0127] Among them, S o , S g and S w It can represent oil saturation, gas saturation and water saturation respectively.

[0128] In some embodiments of the present specification, the capillary pressure equation established by the second establishing module 902 may be expressed by the following formula:

[0129]

[0130] Among them, P cow It can represent the capillary pressure of oil and water phases; P cog It can express the capillary pressure of oil and gas phases; σ ow It can represent the interfacial tension between oil and water phases; σ og It can express the interfacial tension between oil and gas phases; θ ow It can represent the contact angle between oil and water phases; θ og It can represent the contact angle between oil and gas phases; φ m Can represent the matrix porosity; K m Can represent matrix permeability; c o 、c w and c g It can represent the oil phase capillary entry pressure, water phase capillary entry pressure and gas phase capillary entry pressure respectively; a o 、a w and a g It can represent the oil phase capillary number, water phase capillary number and gas phase capillary number respectively; S o , S w and S g It can represent oil saturation, water saturation and gas saturation respectively; S or , S wr and S gr They can represent residual oil saturation, irreducible water saturation and residual gas saturation respectively.

[0131] In some embodiments of the present specification, the three-phase permeability equation established by the second establishment module 902 can be expressed by the following formula:

[0132]

[0133] in, It can represent the relative permeability of oil phase, gas phase and water phase in the three-phase relative permeability respectively; S' o , S' w and S' g It can represent the normalized oil saturation, normalized water saturation and normalized gas saturation respectively; K row It can express the relative permeability of the oil phase in the oil-water phase; K rwg It can express the relative permeability of water phase in gas-water phase; K rog It can express the relative permeability of the oil phase in the oil and gas phases; K rgwIt can express the relative permeability of gas phase in oil and gas phases; K rwo It can express the relative permeability of water phase in oil-water phase; K rgo It can express the relative permeability of gas phase in oil and gas phase.

[0134] In some embodiments of the present specification, the crossflow equation established by the second establishment module 902 can be expressed by the following formula:

[0135]

[0136] Among them, q omf ,q gmf and q wmf can represent the oil phase crossover rate, gas phase crossover rate and water phase crossover rate between fractures and matrix respectively; σ can represent the shape factor of the contact area between artificial fractures and matrix per unit volume of rock; K m It can represent the matrix permeability; and It can represent the relative permeability of oil phase, gas phase and water phase in the three-phase relative permeability respectively; μ o , μ g and μ w It can represent the viscosity of oil phase, gas phase and water phase respectively; B om , B gm and B wm can represent the oil phase volume coefficient, gas phase volume coefficient and water phase volume coefficient in the matrix respectively; P om , P gm and P wm can represent the oil phase pressure, gas phase pressure and water phase pressure in the matrix respectively; P of , P gf and P wf It can represent the oil phase pressure, gas phase pressure and water phase pressure in artificial fractures respectively.

[0137] In some embodiments of the present specification, the production capacity calculation module 903 can be specifically used to: determine the initial conditions and boundary conditions of the calculation based on the basic parameters of the tight reservoir in the target area; decompose the first seepage control equation and the second seepage control equation into a pressure equation and a saturation equation based on the three-phase seepage auxiliary equation; based on the initial conditions and the boundary conditions, use the implicit pressure display saturation method to solve the pressure equation and the saturation equation to obtain the production capacity data.

[0138] In some embodiments of the present specification, the device may also include a parameter optimization module, which is specifically used to: based on the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation, simulate the seepage process of the tight reservoir in the target area by adjusting the engineering parameters to obtain simulation data; determine the change relationship between each parameter in the engineering parameters and the production capacity data based on the simulation data, and optimize each parameter based on the determined change relationship.

[0139] The description and functions of the above modules can be found in Tight Reservoir CO 2 -The content of the WAG oil recovery and storage capacity calculation method is not elaborated here.

[0140] The present application also provides an electronic device, such as Fig.10 As shown, the electronic device may include a processor 1001 and a memory 1002, wherein the processor 1001 and the memory 1002 may be connected via a bus or other means. Fig.10 The example of connecting through bus is taken in the following.

[0141] The processor 1001 may be a central processing unit (CPU). The processor 1001 may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips.

[0142] The memory 1002 is a non-transitory computer-readable storage medium that can be used to store non-transitory software programs, non-transitory computer executable programs, and modules, such as the tight reservoir CO2 storage medium in the embodiment of the present invention. 2 - Program instructions / modules corresponding to the WAG flooding and storage capacity calculation method (e.g. Fig. 9 The processor 1001 executes various functional applications and data processing of the processor by running the non-transient software programs, instructions and modules stored in the memory 1002, that is, realizing the CO2 reduction of the tight reservoir in the above method embodiment. 2 -WAG oil recovery and storage capacity calculation method.

[0143] The memory 1002 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required by at least one function; the data storage area may store data created by the processor 1001, etc. In addition, the memory 1002 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 1002 may optionally include a memory remotely arranged relative to the processor 1001, and these remote memories may be connected to the processor 1001 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0144] The one or more modules are stored in the memory 1002, and when executed by the processor 1001, the following method for calculating the oil recovery and storage capacity of CO2-WAG in a tight reservoir is performed:

[0145] According to the laws of conservation of mass and momentum, a first seepage control equation characterizing the three-phase seepage control of the matrix system and a second seepage control equation characterizing the three-phase seepage control of the artificial fracture system are constructed; a three-phase seepage auxiliary equation is established, and the three-phase seepage auxiliary equation includes a saturation equation, a rock state equation, a capillary pressure equation considering phase permeability hysteresis and a three-phase phase permeability equation, a gas diffusion equation, and a crossflow equation between the matrix and the artificial fracture; based on the basic parameters of the tight reservoir in the target area, the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation are solved to calculate the CO 2 -WAG oil recovery and storage capacity data.

[0146] The specific details of the above electronic device can be understood by referring to the corresponding descriptions and effects in the above method embodiments, and will not be repeated here.

[0147] This specification also provides a computer storage medium, wherein the computer storage medium stores computer program instructions, and when the computer program instructions are executed, the above-mentioned tight reservoir CO 2 -Steps of the WAG flooding and storage capacity calculation method.

[0148] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, the storage medium can be a disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD), etc.; the storage medium can also include a combination of the above-mentioned types of memory.

[0149] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0150] The systems, devices, modules or units described in the above embodiments may be implemented by computer chips or entities, or by products with certain functions.

[0151] For the convenience of description, the above device is described in various units according to their functions. Of course, when implementing the present application, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0152] It can be known from the description of the above implementation methods that those skilled in the art can clearly understand that the present application can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present application can be essentially or partly contributed to the prior art in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute certain parts of the methods of each implementation method of the present application.

[0153] The present application can be used in many general or special computer system environments or configurations, such as personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronic devices, network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above systems or devices, etc.

[0154] The present application may be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The present application may also be practiced in distributed computing environments where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules may be located in local and remote computer storage media, including storage devices.

[0155] Although the present application has been described through embodiments, those skilled in the art will appreciate that there are many modifications and variations to the present application without departing from the spirit of the present application, and it is intended that the appended claims include these modifications and variations without departing from the spirit of the present application.

Claims

1. A method for calculating the production capacity of CO2-WAG oil recovery and storage in tight reservoirs, characterized in that: include: According to the laws of conservation of mass and conservation of momentum, a first seepage control equation characterizing the three-phase seepage control of the matrix system and a second seepage control equation characterizing the three-phase seepage control of the artificial fracture system are constructed; Establishing a three-phase seepage auxiliary equation, wherein the three-phase seepage auxiliary equation includes a saturation equation, a rock state equation, a capillary pressure equation considering phase permeability hysteresis and a three-phase phase permeability equation, a gas diffusion equation, and a cross-flow equation between the matrix and the artificial fracture; The first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation are solved based on the basic parameters of the tight reservoir in the target area, and the CO2-WAG oil recovery and storage capacity data of the tight reservoir are calculated.

2. The method for calculating the capacity of CO2-WAG oil recovery and storage in tight reservoirs according to claim 1, characterized in that: The first seepage control equation is expressed by the following formula: Among them, ▽ represents the Hamiltonian operator; ρ o , g and ρ w Respectively represent the density of oil phase, gas phase and water phase; K m represents the matrix permeability; and Respectively represent the relative permeability of oil phase, gas phase and water phase in the three-phase relative permeability; μ o , μ g and μ w Respectively represent the viscosity of oil phase, gas phase and water phase; B o , B g and B w represent the oil phase volume coefficient, gas phase volume coefficient and water phase volume coefficient respectively; P m represents the matrix pressure; G o , G g and G w They represent the oil phase starting pressure gradient, gas phase starting pressure gradient and water phase starting pressure gradient respectively; q o ,q g and q w They represent the oil phase injection rate or production rate, gas phase injection rate or production rate, and water phase injection rate or production rate respectively; q omf ,q gmf and q wmf They represent the oil phase cross-flow rate, gas phase cross-flow rate and water phase cross-flow rate between fractures and matrix respectively; represents the matrix porosity; S om , S gm and S wm Respectively represent the oil saturation, gas saturation and water saturation in the matrix; F om represents the diffusion flux of carbon dioxide into crude oil; The second seepage control equation is expressed by the following formula: Among them, K f represents the permeability of artificial fractures; P f Indicates the artificial fracture pressure; Indicates the porosity of artificial fractures; S of , S gf and S wf They represent the oil saturation, gas saturation and water saturation in the artificial fractures respectively.

3. The method for calculating the capacity of CO2-WAG oil recovery and storage in tight reservoirs according to claim 1, characterized in that: The rock state equation is expressed by the following formula: in, and represent matrix porosity and artificial fracture porosity, respectively; and represent the matrix porosity and artificial fracture porosity under atmospheric pressure respectively; C m and C f represent the rock compression coefficients of the matrix system and artificial fracture system respectively; P m and P f represent the matrix pressure and artificial fracture pressure respectively, P a Indicates atmospheric pressure; The saturation equation is expressed by the following formula: S o +S g +S w =1; Among them, S o , S g and S w They represent oil saturation, gas saturation and water saturation respectively.

4. The method for calculating the capacity of CO2-WAG oil recovery and storage in tight reservoirs according to claim 1, characterized in that: The capillary pressure equation is expressed by the following formula: Among them, P cow Indicates the capillary pressure of oil and water phases; P cog Indicates the capillary pressure of oil and gas phases; σ ow represents the interfacial tension between oil and water phases; σ og represents the interfacial tension between oil and gas phases; θ ow represents the contact angle between oil and water phases; θ og Represents the contact angle between oil and gas phases; φ m represents the matrix porosity; K m represents the matrix permeability; c o 、c w and c g Respectively represent the capillary entry pressure of oil phase, water phase and gas phase; a o 、a w and a g They represent the capillary number of oil phase, water phase and gas phase, respectively; S o , S w and S g Respectively represent oil saturation, water saturation and gas saturation; S or , S wr and S gr They represent residual oil saturation, irreducible water saturation and residual gas saturation respectively.

5. The method for calculating the capacity of CO2-WAG oil recovery and storage in tight reservoirs according to claim 1, characterized in that: The three-phase permeability equation is expressed by the following formula: in, and Respectively represent the relative permeability of the oil phase, the relative permeability of the gas phase and the relative permeability of the water phase in the three-phase relative permeability; S' o , S' w and S' g represent the normalized oil saturation, normalized water saturation and normalized gas saturation respectively; K row Represents the relative permeability of the oil phase in the oil-water phase; K rwg Represents the relative permeability of water phase in gas-water phase; K rog Represents the relative permeability of the oil phase in the oil and gas phases; K rgw Indicates the relative permeability of gas phase in oil and gas phases; K rwo Represents the relative permeability of water phase in oil-water phase; K rgo It represents the relative permeability of gas phase in oil and gas phase.

6. The method for calculating the capacity of CO2-WAG oil recovery and storage in tight reservoirs according to claim 1, characterized in that: The cross-flow equation is expressed by the following formula: Among them, q omf ,q gmf and q wmf represents the oil phase cross-flow, gas phase cross-flow and water phase cross-flow between fractures and matrix respectively; σ represents the shape factor of the contact area between artificial fractures and matrix per unit volume of rock; K m represents the matrix permeability; and Respectively represent the relative permeability of oil phase, gas phase and water phase in the three-phase relative permeability; μ o , μ g and μ w Respectively represent the viscosity of oil phase, gas phase and water phase; B om , B gm and B wm represent the volume coefficient of oil phase, gas phase and water phase in the matrix respectively; P om , P gm and P wm Respectively represent the oil phase pressure, gas phase pressure and water phase pressure in the matrix; P of , P gf and P wf They represent the oil phase pressure, gas phase pressure and water phase pressure in the artificial fractures respectively.

7. The method for calculating the capacity of CO2-WAG oil recovery and storage in tight reservoirs according to claim 1, characterized in that: The first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation are solved based on the basic parameters of the tight reservoir in the target area to calculate the production capacity data of CO2-WAG flooding and storage of the tight reservoir, including: Determining initial conditions and boundary conditions for calculation based on basic parameters of the tight reservoir in the target area; Decomposing the first seepage control equation and the second seepage control equation into a pressure equation and a saturation equation based on the three-phase seepage auxiliary equation; Based on the initial conditions and the boundary conditions, the implicit pressure-explicit saturation method is used to solve the pressure equation and the saturation equation to obtain the production capacity data.

8. The method for calculating the capacity of CO2-WAG oil recovery and storage in tight reservoirs according to claim 1, characterized in that: After establishing the three-phase seepage auxiliary equation, it also includes: Based on the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation, the seepage process of the tight reservoir in the target area is simulated by adjusting engineering parameters to obtain simulation data; Based on the simulation data, the change relationship between each parameter in the engineering parameters and the production capacity data is determined, and each parameter is optimized based on the determined change relationship.

9. A device for calculating the production capacity of CO2-WAG oil recovery and storage in a tight reservoir, characterized in that: include: A first building module is used to construct a first seepage control equation characterizing the three-phase seepage control of the matrix system and a second seepage control equation characterizing the three-phase seepage control of the artificial fracture system according to the laws of conservation of mass and conservation of momentum; The second establishment module is used to establish a three-phase seepage auxiliary equation, which includes a saturation equation, a rock state equation, a capillary pressure equation considering phase permeability hysteresis and a three-phase phase permeability equation, a gas diffusion equation, and a crossflow equation between the matrix and the artificial fracture; The capacity calculation module is used to solve the first seepage control equation, the second seepage control equation and the three-phase seepage auxiliary equation based on the basic parameters of the tight reservoir in the target area, and calculate the CO2-WAG oil recovery and storage capacity data of the tight reservoir.

10. An electronic device, characterized in that: include: A memory and a processor, wherein the processor and the memory are communicatively connected to each other, the memory stores computer instructions, and the processor implements the steps of the method according to any one of claims 1 to 8 by executing the computer instructions.

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