Method, device and equipment for determining maximum operating pressure of gas reservoir type gas storage

Abstract

The invention discloses a method, a device and equipment for determining the maximum operating pressure of a gas reservoir type gas storage. The method comprises the following steps: constructing a seepage-geomechanical model of a target gas storage; performing historical fitting on the basis of the reservoir relative permeability curve, the reservoir PVT parameters, the seepage-geomechanical model and the ground mining data of the target gas storage, and determining formation pressure change data and formation temperature change data in the injection-production process of the target gas storage; and expanding the geomechanical grid based on the reservoir physical property parameters and the covering layer physical property parameters, applying boundary conditions to the expanded geomechanical grid based on the formation pressure change data and the formation temperature change data, and determining the highest operating pressure of the target gas storage after performing geomechanical calculation on the seepage-geomechanical model. The method is based on geomechanical model simulation, the calculated maximum operating pressure of the gas storage is more real and reliable, and an important technical support is provided in the design of a gas storage capacity expansion scheme.

Description

Technical Field

[0001] The present invention relates to the technical field of underground natural gas storage, and in particular to a method, device and equipment for determining the maximum operating pressure of a gas reservoir type gas storage. Background Art

[0002] Typical gas reservoir-type gas storage facilities operate at or below the original reservoir pressure due to concerns about reservoir integrity, fracturing, faulting, and gas loss. However, in actual operation, it is found that the current method of selecting the maximum operating pressure limit based on the initial discovery pressure is often too conservative, which will lead to insufficient utilization of existing storage resources and thus competition restrictions on specific projects. The determination of the maximum operating pressure of a gas storage facility has always been an engineering problem. When the maximum operating pressure is less than the maximum true operating pressure, the gas storage potential of the gas storage facility cannot be fully developed; when the maximum operating pressure is greater than the maximum true operating pressure, the gas storage formation will be broken, resulting in natural gas leakage. In severe cases, the gas storage facility will be scrapped, which will not only cause economic losses, but also have a serious impact on the ecological environment.

[0003] In many cases, if the geomechanical properties of the reservoir and overburden are well defined, it is possible to safely increase the pressure in the reservoir. Many existing gas storage facilities that operate under normal pressure conditions and have reservoirs that also operate at relatively low pressures relative to the overburden stresses are good candidates for increasing the maximum operating pressure. Summary of the invention

[0004] In order to increase the maximum operating pressure of a gas storage and increase the selection space, a method, device and equipment for determining the maximum operating pressure of a gas reservoir type gas storage are provided in an embodiment of the present invention.

[0005] In a first aspect, an embodiment of the present invention provides a method for determining the maximum operating pressure of a gas reservoir type gas storage, which may include:

[0006] Based on the reservoir physical property parameters, overburden physical property parameters, seismic interpretation data and well logging interpretation data of the target gas storage, a seepage-geomechanical model of the target gas storage is constructed;

[0007] Based on the reservoir relative permeability curve, the reservoir PVT parameters, the seepage-geomechanical model, and the well production data of the target gas storage, historical matching is performed to determine the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage;

[0008] The geomechanical grid in the seepage-geomechanical model is expanded based on the reservoir physical property parameters and the overburden physical property parameters, and boundary conditions are applied to the expanded geomechanical grid based on the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage reservoir, so as to determine the maximum operating pressure of the target gas storage reservoir after geomechanical calculation of the seepage-geomechanical model.

[0009] Optionally, determining the maximum operating pressure of the target gas storage after performing geomechanical calculation on the seepage-geomechanical model may include:

[0010] Performing geomechanical calculations on the seepage-geomechanical model to obtain effective stress, shear stress and displacement deformation data of the reservoir, overburden and fracture, and evaluating the change of stress at the fracture with reservoir pressure;

[0011] The stress change caused by the injection-production cycle is compared with the stress change at the fracture with the reservoir pressure to determine the maximum operating pressure of the target gas storage.

[0012] Optionally, comparing the stress change caused by the injection-production cycle with the stress change at the fracture with the reservoir pressure to determine the maximum operating pressure of the target gas storage reservoir may include:

[0013] Compare the effective stress results of the reservoir and overburden obtained by numerical simulation with the reservoir physical property parameters and overburden physical property parameters obtained in advance in the laboratory to determine whether the reservoir and overburden have been tensile damaged;

[0014] Based on the change of stress at the fault with reservoir pressure and the fault slip index obtained by DSA analysis, it is determined whether the fault has slipped;

[0015] The maximum operating pressure of the target gas storage is determined based on whether the reservoir and the overburden are subjected to tensile damage and whether the faults are subjected to slippage.

[0016] Optionally, the determining of formation pressure change data and formation temperature change data during the injection and production process of the target gas storage by performing history matching based on the reservoir relative permeability curve, the reservoir PVT parameter, the seepage-geomechanics model, and the well production data of the target gas storage to determine the formation pressure change data and formation temperature change data during the injection and production process of the target gas storage may include:

[0017] The reservoir relative permeability curve and the reservoir PVT parameters are used as attribute inputs of the software Re module, and historical fitting is performed based on the existing well production data to obtain the formation pressure change data from the production of oil and gas reservoirs to the present;

[0018] Based on the operational measurements of the gas storage design, seepage mechanics simulation is performed to obtain formation pressure change data and temperature change data for different parts of the reservoir and overburden layer at different time points throughout the life cycle of the gas storage.

[0019] Optionally, before constructing the seepage-geomechanical model of the target gas storage, the following steps may also be included:

[0020] Acquiring reservoir physical property parameters and overburden physical property parameters of the target gas storage, as well as seismic interpretation data and well logging interpretation data of the target gas storage;

[0021] The reservoir physical property parameters and overburden physical property parameters include: reservoir mechanical property parameters, reservoir structural parameters, reservoir fracturing parameters, overburden mechanical property parameters, overburden structural parameters, and fault mechanical property parameters in the reservoir and overburden;

[0022] The reservoir mechanical performance parameters include: reservoir stiffness characteristics, reservoir strength characteristics; the reservoir structural parameters include: reservoir porosity, reservoir permeability; the reservoir fracturing parameters include: reservoir fracture pressure and reservoir initial geostress;

[0023] The mechanical performance parameters of the covering layer include: the stiffness characteristics of the covering layer and the strength characteristics of the covering layer;

[0024] The cover layer structural parameters include: cover layer breakthrough pressure;

[0025] The fracture mechanics performance parameters include: fracture stiffness characteristics and fracture strength characteristics.

[0026] In a second aspect, an embodiment of the present invention provides a method for adjusting operating parameters of a gas reservoir type gas storage, wherein the operating parameters of the gas reservoir type gas storage include: a minimum operating pressure and a maximum operating pressure;

[0027] Wherein, the maximum operating pressure is determined based on the method for determining the maximum operating pressure of a gas reservoir-type gas storage facility as described in the first aspect.

[0028] In a third aspect, an embodiment of the present invention provides a device for determining the maximum operating pressure of a gas reservoir type gas storage, which may include:

[0029] A model building module, used to build a seepage-geomechanical model of the target gas storage based on the reservoir physical property parameters, overburden physical property parameters, seismic interpretation data and well logging interpretation data of the target gas storage;

[0030] A change data determination module is used to perform history matching based on the reservoir relative permeability curve, the reservoir PVT parameters, the seepage-geomechanics model, and the well production data of the target gas storage to determine the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage;

[0031] A maximum operating pressure determination module is used to expand the geomechanical grid in the seepage-geomechanical model based on the reservoir physical property parameters and the overburden physical property parameters, so as to apply boundary conditions to the expanded geomechanical grid based on the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage reservoir, so as to determine the maximum operating pressure of the target gas storage reservoir after performing geomechanical calculations on the seepage-geomechanical model.

[0032] Optionally, the device may further include: an acquisition module, used to acquire reservoir physical property parameters and overburden physical property parameters of the target gas storage, as well as seismic interpretation data and well logging interpretation data of the target gas storage;

[0033] The reservoir physical property parameters and overburden physical property parameters include: reservoir mechanical property parameters, reservoir structural parameters, reservoir fracturing parameters, overburden mechanical property parameters, overburden structural parameters, and fault mechanical property parameters in the reservoir and overburden;

[0034] The reservoir mechanical performance parameters include: reservoir stiffness characteristics, reservoir strength characteristics; the reservoir structural parameters include: reservoir porosity, reservoir permeability; the reservoir fracturing parameters include: reservoir fracture pressure and reservoir initial geostress;

[0035] The mechanical performance parameters of the covering layer include: the stiffness characteristics of the covering layer and the strength characteristics of the covering layer;

[0036] The cover layer structural parameters include: cover layer breakthrough pressure;

[0037] The fracture mechanics performance parameters include: fracture stiffness characteristics and fracture strength characteristics.

[0038] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for determining the maximum operating pressure of a gas reservoir-type gas storage facility as described in the first aspect.

[0039] In a fourth aspect, an embodiment of the present invention provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for determining the maximum operating pressure of a gas reservoir-type gas storage facility as described in the first aspect is implemented.

[0040] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0041] The embodiment of the present invention provides a method, device and equipment for determining the maximum operating pressure of a gas reservoir-type gas storage. The method utilizes drilling and logging data, combines test results, and uses a geomechanical model for simulation. The calculated maximum operating pressure of the gas storage is more realistic and reliable. The maximum operating pressure of the gas storage determined by the present invention can provide important technical support in the design of gas storage expansion plans.

[0042] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0043] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0045] Figure 1 A flow chart of a method for determining the maximum operating pressure of a gas reservoir type gas storage provided in an embodiment of the present invention;

[0046] Figure 2 One of the flowcharts of the method for determining the maximum operating pressure of a gas reservoir type gas storage provided in the embodiment of the present invention;

[0047] Figure 3 The second flowchart of the method for determining the maximum operating pressure of a gas reservoir type gas storage provided in the embodiment of the present invention is detailed;

[0048] Figure 4 A displacement pressure curve diagram of a core sample provided in an embodiment of the present invention;

[0049] Figure 5 A permeability evolution curve diagram of a core sample alternating sealing test provided in an embodiment of the present invention;

[0050] Figure 6 A stress-strain curve diagram of a triaxial compression test of a core sample provided in an embodiment of the present invention;

[0051] Figure 7 An example of a field model diagram of a target gas storage provided in an embodiment of the present invention;

[0052] Figure 8 A formation pressure curve variation diagram obtained by seepage mechanics calculation provided in an embodiment of the present invention;

[0053] Fig. 9 The expanded geomechanical model diagram provided in the embodiment of the present invention;

[0054] Fig.10 The cloud diagram of effective vertical stress of the overburden layer of 1.5 times the formation pressure provided in the embodiment of the present invention;

[0055] Fig.11 The effective horizontal stress cloud diagram of the overburden layer of 1.5 times the formation pressure provided in the embodiment of the present invention;

[0056] Fig.12 The cloud diagram of effective vertical stress of a reservoir at 1.5 times the formation pressure provided in the embodiment of the present invention;

[0057] Fig.13 The cloud diagram of effective horizontal stress of a reservoir at 1.5 times the formation pressure provided in the embodiment of the present invention;

[0058] Fig.14 It is a Mohr-Coulomb diagram of the reservoir at 1.5 times the formation pressure provided in an embodiment of the present invention;

[0059] Fig.15 The Mohr-Coulomb diagram of the overburden layer at 1.5 times the formation pressure provided in the embodiment of the present invention;

[0060] Fig.16 The Mohr-Coulomb diagram of the fault with the maximum operating pressure of 1.4 times the formation pressure provided in the embodiment of the present invention;

[0061] Fig.17 The Mohr-Coulomb diagram of the fault with the maximum operating pressure of 1.5 times the formation pressure provided in the embodiment of the present invention;

[0062] Fig.18 It is a schematic structural diagram of a device for determining the maximum operating pressure of a gas reservoir type gas storage provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0063] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0064] The inventors found that the existing methods for increasing the maximum operating pressure mainly include the minimum principal stress determination method and the original gas reservoir pressure determination method. However, the minimum principal stress determination method only considers the minimum principal stress of the gas storage reservoir, but does not consider the rock characteristic parameters of the gas storage reservoir; the original gas reservoir pressure determination method uses the original gas reservoir pressure before the reservoir is built as the maximum operating pressure for expansion. This pressure is often conservative and cannot represent the actual pressure that the gas storage formation can withstand. The latest method for increasing the maximum operating pressure in the prior art takes into account the impact on the rock characteristics of the gas storage reservoir, and uses the improved Huang Rongzun model to predict the formation fracture pressure.

[0065] In general, the existing methods for increasing the maximum operating pressure of gas reservoir-type gas storage are still at the stage of combining experiments and analytical solutions, and are unable to accurately evaluate the reservoir rupture pressure of gas storage. With the development of gas storage, more and more engineering problems and complex working conditions have emerged, and the existing methods cannot be applied to all situations. The inventors have found that numerical simulation technology is becoming increasingly mature, and most of the industry has begun to use geomechanical integrated software for prediction. There is an urgent need for a method to use numerical simulation technology to increase the maximum operating pressure of gas reservoir-type gas storage, and then evaluate the reservoir rupture pressure of gas storage, so as to provide strong technical support for the expansion and production of existing gas storage. In view of the above problems, the present invention is proposed to provide a method, device and equipment for determining the maximum operating pressure of a gas reservoir-type gas storage that overcomes the above problems or at least partially solves the above problems.

[0066] In an embodiment of the present invention, a method for determining the maximum operating pressure of a gas reservoir type gas storage is provided. Figure 1 As shown, the method may include the following steps:

[0067] Step S11: constructing a seepage-geomechanical model of the target gas storage based on the reservoir physical property parameters, overburden physical property parameters, seismic interpretation data and well logging interpretation data of the target gas storage.

[0068] Step S12: Perform history fitting based on the reservoir relative permeability curve, reservoir PVT parameters, seepage-geomechanical model, and well production data of the target gas storage to determine the formation pressure change data and formation temperature change data during the injection and production process of the target gas storage.

[0069] In this step, the reservoir relative permeability curve and reservoir PVT parameters are first used as attribute inputs of the software Re module, and historical fitting is performed based on the existing well production data to obtain the formation pressure change data from oil and gas reservoir production to the present; then, based on the operational measurements of the gas storage design, seepage mechanics simulation is performed to obtain the formation pressure change data and temperature change data of different parts of the reservoir and overburden at different time nodes throughout the life cycle of the gas storage.

[0070] Step S13: Expand the geomechanical grid in the seepage-geomechanical model based on the reservoir physical property parameters and the overburden physical property parameters, and apply boundary conditions to the expanded geomechanical grid based on the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage reservoir, so as to determine the maximum operating pressure of the target gas storage reservoir after performing geomechanical calculations on the seepage-geomechanical model.

[0071] This step first performs geomechanical calculations on the seepage-geomechanical model to obtain the effective stress, shear stress and displacement deformation data of the reservoir, overburden and fault, and evaluates the change of stress at the fault with reservoir pressure; then, the stress change caused by the injection-production cycle is compared with the change of stress at the fault with reservoir pressure to determine the maximum operating pressure of the target gas storage.

[0072] Specifically, the effective stress results of the reservoir and overburden obtained by numerical simulation are compared with the reservoir physical property parameters and overburden physical property parameters obtained in advance in the laboratory to determine whether tensile damage has occurred in the reservoir and overburden; based on the change of stress at the fracture with reservoir pressure and the fault slip index obtained by DSA analysis, it is determined whether slip has occurred in the fracture; based on whether tensile damage has occurred in the reservoir and overburden and whether slip has occurred in the fracture, the maximum operating pressure of the target gas storage is determined.

[0073] The above method for determining the maximum operating pressure of a gas reservoir type gas storage uses drilling and logging data, combined with test results, and simulated using a geomechanical model. The calculated maximum operating pressure of the gas storage is more realistic and reliable. The maximum operating pressure of the gas storage determined by the present invention can provide important technical support in the design of a gas storage expansion plan.

[0074] In another optional embodiment, before executing step S11, the following steps need to be performed, namely:

[0075] Step S10, obtaining reservoir physical property parameters and overburden physical property parameters of the target gas storage, as well as seismic interpretation data and well logging interpretation data of the target gas storage;

[0076] Among them, the reservoir physical property parameters and the overburden physical property parameters may include: reservoir mechanical property parameters, reservoir structural parameters, reservoir fracturing parameters, overburden mechanical property parameters, overburden structural parameters, and fault mechanical property parameters in the reservoir and overburden; the reservoir mechanical property parameters may include: reservoir stiffness characteristics, reservoir strength characteristics; the reservoir structural parameters may include: reservoir porosity, reservoir permeability; the reservoir fracturing parameters may include: reservoir fracture pressure and reservoir initial geostress; the overburden mechanical property parameters may include: overburden stiffness characteristics, overburden strength characteristics; the overburden structural parameters may include: overburden breakthrough pressure; the fracture mechanical property parameters may include: fracture stiffness characteristics, fracture strength characteristics.

[0077] In a detailed embodiment, referring to Figure 2 and Figure 3 As shown, the method for determining the maximum operating pressure of the gas reservoir type gas storage facility may specifically include the following steps:

[0078] Step S21, determining the mechanical property parameters and structural parameters of the reservoir and overburden of the target gas storage.

[0079] In this step, the mechanical properties and structural parameters of the rocks in the reservoir and overburden are obtained through laboratory analysis. The stiffness and strength characteristics of the rocks and the microscopic structural parameters need to be measured on core samples. If there are no core samples and analysis and measurement cannot be performed, the mechanical properties and structural parameters of the rocks are estimated based on existing geological or seismic data. For example, if there are no core samples, the rock stiffness characteristics are mainly determined by acoustic logging, and the compression velocity and shear velocity characteristics are recorded at the same time. The rock strength characteristics are linked to the stiffness characteristics or velocity using empirical correlations. The data used for the microscopic structural parameters are mainly the attribute curves and corresponding attribute inversion bodies at the well points. The compressive or shear strength and microscopic related structural parameters can be estimated based on some empirical correlation rock stiffness values.

[0080] In the specific implementation of this step, the present embodiment removes a core sample with a diameter of 25 mm and a height of 50 mm, and uses the core sample to pass the displacement pressure test (refer to Figure 4 As shown), alternating sealing test (refer to Figure 5 As shown), uniaxial tensile test, triaxial compression test (refer to Figure 6 As shown in the figure), alternating fatigue test, mudstone friction test, mudstone shear test, etc. are used to obtain the stiffness and strength characteristics of the mechanical performance parameters of the reservoir, overburden and fault at different positions, as well as the relevant micro-structural parameters such as porosity, permeability and breakthrough pressure.

[0081] Step S22: Determine the fracturing parameters of the reservoir.

[0082] The reservoir fracturing parameters in the embodiment of the present invention include: reservoir fracture pressure and reservoir initial geostress. In the specific implementation, this step can be carried out by using the same hydraulic fracturing test to determine the reservoir fracturing parameters at multiple locations of the target gas storage. If there is no hydraulic fracturing measurement data, available leakage and borehole fracture data can be used to provide a reasonable estimate of the minimum stress value, and then the vertical well borehole is measured and analyzed to provide the stress direction.

[0083] The above steps S21 and S22 are preliminary data preparation work for modeling, which lays the foundation for establishing the seepage-geomechanical model of the target gas storage in the subsequent step S23, and provides support for the geomechanical calculation in the subsequent steps. It should be noted that the above steps S21 and S22 can be executed in no particular order, and can be executed simultaneously.

[0084] Step S23: constructing a seepage-geomechanical model of the target gas storage based on the reservoir physical property parameters, overburden physical property parameters, seismic interpretation data and well logging interpretation data of the target gas storage.

[0085] In this step, structural modeling and attribute modeling are carried out based on seismic interpretation data and well logging interpretation data, and geostress modeling is carried out based on reservoir physical property parameters and overburden physical property reference. Figure 7 As shown, a seepage-geomechanical model of the target gas storage reservoir is finally constructed. It should be noted that, in the embodiment of the present invention, the PETREL geological engineering integrated software can be used to construct the above-mentioned seepage-geomechanical model.

[0086] Step S24: Perform history fitting based on the reservoir relative permeability curve, reservoir PVT parameters, seepage-geomechanical model, and well production data of the target gas storage to determine the formation pressure change data and formation temperature change data during the injection and production process of the target gas storage.

[0087] In this step, the reservoir relative permeability curve and reservoir PVT parameters are first used as the attribute input of the Re module of the above-mentioned software, and historical fitting is performed according to the existing well production data to obtain the formation pressure change data from oil and gas reservoir production to the present; then, according to the operation strategy designed for the gas storage, the seepage mechanics simulation is performed to obtain the formation pressure change data of different parts of the reservoir and overburden at different time points throughout the life cycle of the gas storage (refer to Figure 8 shown) and temperature variation data.

[0088] Step S25: Expand the geomechanical grid in the seepage-geomechanical model based on the reservoir physical property parameters and the overburden physical property parameters.

[0089] The geomechanical model after the grid expansion in the embodiment of the present invention is a geomechanical model established based on the reservoir seepage model. Generally, the boundary effect is eliminated and an isolation body is set, including an overburden layer, an underburden layer and a lateral layer; a rigid plate (50m) is set around to load stress; the lateral layer is expanded from the I and J directions with a triple reservoir model to obtain a reference Fig. 9 The expanded geomechanical model is shown.

[0090] In the specific implementation of this step, the visage module in the software is used to assign block attributes to the expanded overburden, underburden and lateral overburden. When assigning attributes, it can be based on the average values ​​of the mechanical performance parameters and structural parameters of the test results of each formation determined in the above step S21.

[0091] Step S26: applying boundary conditions to the expanded geomechanical grid based on the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage reservoir, so as to perform geomechanical calculations on the seepage-geomechanical model.

[0092] In this step, the formation pressure change data and the formation temperature change data determined in the above step S24 are used as the boundary conditions of the above expanded geomechanical grid to perform geomechanical calculations on the seepage-geomechanical model. In specific implementation, the results of the above formation pressure change data and formation temperature change data are imported into the visage module of the software. After the boundary conditions are applied, the geomechanical calculation can be started to obtain the results of effective stress, shear stress and deformation of the reservoir, overburden and fracture.

[0093] It should be noted that the fractures in this embodiment include faults and cracks in the reservoir and the overburden.

[0094] Step S27, evaluating the change of stress at the fracture with reservoir pressure.

[0095] This step is based on DSA (Dscontinuity Stability Analysis) analysis to determine whether faults and cracks are activated under different pressure conditions. Figure 10 to Figure 13 The plastic and elastic stress, strain and displacement data of the faults and cracks are used to determine the stability of the faults and cracks. At the same time, DSA (Dscontinuity Stability Analysis) is used to determine whether the faults and cracks are activated under different pressure conditions.

[0096] Step S28, comparing the stress change caused by the injection-production cycle with the stress change at the fracture along with the reservoir pressure to determine the maximum operating pressure of the target gas storage.

[0097] In the specific implementation, the stress changes caused by the injection-production cycle are compared with the assessed formation strength characteristics, the calculated initial ground stress, the reservoir fracture pressure, the overburden breakthrough pressure and the fault activation pressure. The effective stress results of the reservoir and overburden obtained by numerical simulation are compared with the results obtained in step S21 and step S22 to determine whether tensile failure occurs, and the Mohr-Coulomb failure criterion is used to determine whether shear failure occurs; for faults, the fault slip index is obtained by DSA analysis in step S27. If the result is greater than 1, it means that the fault has slipped, and if the result is less than 1, it means that the fault is stable. The minimum value among several critical values ​​of damage is taken, and the corresponding upper limit pressure is used as the highest operating pressure value that can be increased.

[0098] The calculation process in this step is as follows:

[0099] The stresses caused by injection and production cycles in gas storage are estimated by applying the concept of strain from continuum mechanics: the volumetric strain at a point caused by a local change in pore pressure is considered to be the center of expansion of the elastic half-space. The volumetric strain of a cell is ΔV / V, which is assumed to depend on the change in pore pressure multiplied by the compressibility of the reservoir material, C b .

[0100] ΔV / V=C b ΔP (1)

[0101] The stress of the entire elastic body is determined by the volume changes of the reservoir units. The overburden material is assumed to be linear elastic, isotropic and uniformly distributed. By integrating all these unit volume changes, the total shear stress caused by the different stress changes in the reservoir can be obtained.

[0102]

[0103]

[0104] Where: τ yz , τ xz is the horizontal shear stress at position (x0, y0, z0);

[0105] E0 is the Young’s modulus of the covering material;

[0106] v is the Poisson's ratio of the reservoir and the overburden.

[0107] V1 and V2 are distance functions:

[0108]

[0109]

[0110] ΔP(x,y,z) is the change in pressure measured at a reference state, from which the induced stress can be determined. Equations (2) and (3) can be integrated analytically if the pressure distribution is a simple function, or numerically if the pressure is obtained from a simulation model.

[0111] The Mohr-Coulomb criterion is used to determine whether the formation has been damaged. Geomechanical calculations take into account effective stresses that can be expressed mathematically in damage analysis.

[0112] σ′=σ-αp p (6)

[0113] Where, σ′ is the effective stress, MPa;

[0114] σ is the total stress acting on the rock mass, MPa;

[0115] p pis the reservoir pressure, MPa;

[0116] α is the Biot coefficient.

[0117] When the shear stress exceeds the shear strength of the rock, rock shear failure will occur. The Mohr-Coulomb failure criterion is used to describe the relationship between the effective normal stress, shear stress, and shear strength of the material. If for some reason the Mohr circle touches the failure envelope, rock shear failure will occur. The shear strength of the rock (τ max ) is expressed as:

[0118]

[0119] Where: σ′ n is the normal effective stress, MPa;

[0120] τ max is the shear strength, MPa;

[0121] c is cohesion, MPa;

[0122] is the friction angle, °;

[0123] If the effective stress decreases significantly and falls below the tensile cutoff value (T0), unintended hydraulic fracturing may occur.

[0124] σ′≤T0 (8)

[0125] The tensile cutoff value is negative, indicating the direction opposite to the normal direction of the compressive stress. For conservative analysis, it is assumed that hydraulic fracturing will occur if the minimum effective stress σ′ is lower than 0.

[0126] Reference Fig.14 and Fig.15 As shown in the figure, the effective stress results of the reservoir and cap layer use the Mohr-Coulomb failure criterion to determine whether shear failure occurs. When the maximum operating pressure is 1.5 times the formation pressure, the reservoir and cap layer are not damaged. Fig.16 and Fig.17 As shown in the figure, when the maximum operating pressure is 1.4 times the formation pressure, the fault is relatively safe and no slip occurs. When the maximum operating pressure is 1.5 times the formation pressure, the fault is activated. Therefore, the maximum operating pressure of the gas storage is 1.4 times the formation pressure.

[0127] The above method provided in the embodiment of the present invention utilizes drilling and logging data, combines test results, and uses a geomechanical model for simulation, so that the calculated maximum operating pressure of the gas storage reservoir is more realistic and reliable.

[0128] Based on the same inventive concept, a device for determining the maximum operating pressure of a gas reservoir type gas storage is also provided in an embodiment of the present invention. Fig.18 As shown, it may include: a model building module 11, a change data determination module 12 and a maximum operating pressure determination module 13, and its working principle is as follows:

[0129] The model building module 11 is used to build a seepage-geomechanical model of the target gas storage based on the reservoir physical property parameters, overburden physical property parameters, seismic interpretation data and well logging interpretation data of the target gas storage;

[0130] The change data determination module 12 is used to perform history matching based on the reservoir relative permeability curve, the reservoir PVT parameters, the seepage-geomechanics model, and the well production data of the target gas storage reservoir to determine the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage reservoir;

[0131] The maximum operating pressure determination module 13 is used to expand the geomechanical grid in the seepage-geomechanical model based on the reservoir physical property parameters and the overburden physical property parameters, so as to apply boundary conditions to the expanded geomechanical grid based on the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage reservoir, so as to determine the maximum operating pressure of the target gas storage reservoir after performing geomechanical calculations on the seepage-geomechanical model.

[0132] In an optional embodiment, also refer to Fig.18 As shown, the device may further include: an acquisition module 10, the acquisition module 10 is used to acquire reservoir physical property parameters and overburden physical property parameters of the target gas storage reservoir, as well as seismic interpretation data and well logging interpretation data of the target gas storage reservoir;

[0133] The reservoir physical property parameters and overburden physical property parameters include: reservoir mechanical property parameters, reservoir structural parameters, reservoir fracturing parameters, overburden mechanical property parameters, overburden structural parameters, and fault mechanical property parameters in the reservoir and overburden;

[0134] The reservoir mechanical performance parameters include: reservoir stiffness characteristics, reservoir strength characteristics; the reservoir structural parameters include: reservoir porosity, reservoir permeability; the reservoir fracturing parameters include: reservoir fracture pressure and reservoir initial geostress;

[0135] The mechanical performance parameters of the covering layer include: the stiffness characteristics of the covering layer and the strength characteristics of the covering layer;

[0136] The cover layer structural parameters include: cover layer breakthrough pressure;

[0137] The fracture mechanics performance parameters include: fracture stiffness characteristics and fracture strength characteristics.

[0138] In another optional embodiment, the maximum operating pressure determination module 13 is specifically used to: perform geomechanical calculations on the seepage-geomechanical model to obtain effective stress, shear stress and displacement deformation data of the reservoir, overburden and fracture, and evaluate changes in stress at the fracture with reservoir pressure;

[0139] The stress change caused by the injection-production cycle is compared with the stress change at the fracture with the reservoir pressure to determine the maximum operating pressure of the target gas storage.

[0140] In another optional embodiment, the maximum operating pressure determination module 13 is further used to: compare the effective stress results of the reservoir and the overburden obtained by numerical simulation with the reservoir physical property parameters and the overburden physical property parameters obtained in advance in the laboratory to determine whether the reservoir and the overburden are tensile damaged;

[0141] Based on the change of stress at the fault with reservoir pressure and the fault slip index obtained by DSA analysis, it is determined whether the fault has slipped;

[0142] The maximum operating pressure of the target gas storage is determined based on whether the reservoir and the overburden are subjected to tensile damage and whether the faults are subjected to slippage.

[0143] In another optional embodiment, the change data determination module 12 is specifically used to: use the reservoir phase permeability curve and the reservoir PVT parameter as attribute inputs of the software Re module, perform historical matching based on existing well production data, so as to obtain the formation pressure change data from oil and gas reservoir production to the present;

[0144] Based on the operational measurements of the gas storage design, seepage mechanics simulation is performed to obtain formation pressure change data and temperature change data for different parts of the reservoir and overburden layer at different time points throughout the life cycle of the gas storage.

[0145] Based on the same inventive concept, an embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored, and when the program is executed by a processor, the method for determining the maximum operating pressure of the gas reservoir-type gas storage facility is implemented.

[0146] Based on the same inventive concept, a computer device is also provided in an embodiment of the present invention, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for determining the maximum operating pressure of the gas reservoir-type gas storage facility is implemented.

[0147] Based on the same inventive concept, an embodiment of the present invention further provides a method for adjusting operating parameters of a gas reservoir type gas storage, wherein the operating parameters of the gas reservoir type gas storage include: a minimum operating pressure and a maximum operating pressure;

[0148] Among them, the maximum operating pressure is determined based on the above-mentioned method for determining the maximum operating pressure of the gas reservoir type gas storage.

[0149] The principles of the problems solved by the above-mentioned devices, clients, media, related equipment and systems in the embodiments of the present invention are similar to those of the above-mentioned methods, so their implementation can refer to the implementation of the above-mentioned methods, and the repeated parts will not be repeated.

[0150] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) containing computer-usable program code.

[0151] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0152] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0153] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0154] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for determining the maximum operating pressure of a gas reservoir type gas storage facility, characterized in that: include: Based on the reservoir physical property parameters, overburden physical property parameters, seismic interpretation data and well logging interpretation data of the target gas storage, a seepage-geomechanical model of the target gas storage is constructed; Based on the reservoir relative permeability curve, the reservoir PVT parameters, the seepage-geomechanical model, and the well production data of the target gas storage, historical matching is performed to determine the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage; The geomechanical grid in the seepage-geomechanical model is expanded based on the reservoir physical property parameters and the overburden physical property parameters, and boundary conditions are applied to the expanded geomechanical grid based on the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage reservoir, so as to determine the maximum operating pressure of the target gas storage reservoir after geomechanical calculation of the seepage-geomechanical model.

2. The method according to claim 1, characterized in that: Determining the maximum operating pressure of the target gas storage after performing geomechanical calculations on the seepage-geomechanical model includes: Performing geomechanical calculations on the seepage-geomechanical model to obtain effective stress, shear stress and displacement deformation data of the reservoir, overburden and fracture, and evaluating the change of stress at the fracture with reservoir pressure; The stress change caused by the injection-production cycle is compared with the stress change at the fracture with the reservoir pressure to determine the maximum operating pressure of the target gas storage.

3. The method according to claim 2, characterized in that The comparing the stress change caused by the injection-production cycle with the stress change at the fracture with the reservoir pressure to determine the maximum operating pressure of the target gas storage includes: Compare the effective stress results of the reservoir and overburden obtained by numerical simulation with the reservoir physical property parameters and overburden physical property parameters obtained in advance in the laboratory to determine whether the reservoir and overburden have been tensile damaged; Based on the change of stress at the fault with reservoir pressure and the fault slip index obtained by DSA analysis, it is determined whether the fault has slipped; The maximum operating pressure of the target gas storage is determined based on whether the reservoir and the overburden are subjected to tensile damage and whether the faults are subjected to slippage.

4. The method according to claim 1, characterized in that: The method of performing history matching based on the reservoir relative permeability curve, the reservoir PVT parameters, the seepage-geomechanical model, and the well production data of the target gas storage to determine the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage includes: The reservoir relative permeability curve and the reservoir PVT parameters are used as attribute inputs of the software Re module, and historical fitting is performed based on the existing well production data to obtain the formation pressure change data from the production of oil and gas reservoirs to the present; Based on the operational measurements of the gas storage design, seepage mechanics simulation is performed to obtain formation pressure change data and temperature change data for different parts of the reservoir and overburden at different time points throughout the life cycle of the gas storage.

5. The method according to any one of claims 1 to 4, characterized in that: Before constructing the seepage-geomechanical model of the target gas storage, the method further includes: Acquiring reservoir physical property parameters and overburden physical property parameters of the target gas storage, as well as seismic interpretation data and well logging interpretation data of the target gas storage; The reservoir physical property parameters and overburden physical property parameters include: reservoir mechanical property parameters, reservoir structural parameters, reservoir fracturing parameters, overburden mechanical property parameters, overburden structural parameters, and fault mechanical property parameters in the reservoir and overburden; The reservoir mechanical performance parameters include: reservoir stiffness characteristics, reservoir strength characteristics; the reservoir structural parameters include: reservoir porosity, reservoir permeability; the reservoir fracturing parameters include: reservoir fracture pressure and reservoir initial geostress; The mechanical performance parameters of the covering layer include: the stiffness characteristics of the covering layer and the strength characteristics of the covering layer; The cover layer structural parameters include: cover layer breakthrough pressure; The fracture mechanics performance parameters include: fracture stiffness characteristics and fracture strength characteristics.

6. A method for adjusting operating parameters of a gas reservoir type gas storage, characterized in that: The operating parameters of the gas reservoir type gas storage include: minimum operating pressure and maximum operating pressure; Wherein, the maximum operating pressure is determined based on the method for determining the maximum operating pressure of a gas reservoir-type gas storage facility as described in any one of claims 1 to 5.

7. A device for determining the maximum operating pressure of a gas reservoir type gas storage, characterized in that: include: A model building module, used to build a seepage-geomechanical model of the target gas storage based on the reservoir physical property parameters, overburden physical property parameters, seismic interpretation data and well logging interpretation data of the target gas storage; A change data determination module is used to perform history matching based on the reservoir relative permeability curve, the reservoir PVT parameters, the seepage-geomechanics model, and the well production data of the target gas storage to determine the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage; A maximum operating pressure determination module is used to expand the geomechanical grid in the seepage-geomechanical model based on the reservoir physical property parameters and the overburden physical property parameters, so as to apply boundary conditions to the expanded geomechanical grid based on the formation pressure change data and the formation temperature change data during the injection and production process of the target gas storage reservoir, so as to determine the maximum operating pressure of the target gas storage reservoir after performing geomechanical calculations on the seepage-geomechanical model.

8. The apparatus according to claim 7, further comprising: An acquisition module, used to acquire reservoir physical property parameters and overburden physical property parameters of a target gas storage reservoir, as well as seismic interpretation data and well logging interpretation data of the target gas storage reservoir; The reservoir physical property parameters and overburden physical property parameters include: reservoir mechanical property parameters, reservoir structural parameters, reservoir fracturing parameters, overburden mechanical property parameters, overburden structural parameters, and fault mechanical property parameters in the reservoir and overburden; The reservoir mechanical performance parameters include: reservoir stiffness characteristics, reservoir strength characteristics; the reservoir structural parameters include: reservoir porosity, reservoir permeability; the reservoir fracturing parameters include: reservoir fracture pressure and reservoir initial geostress; The mechanical performance parameters of the covering layer include: the stiffness characteristics of the covering layer and the strength characteristics of the covering layer; The cover layer structural parameters include: cover layer breakthrough pressure; The fracture mechanics performance parameters include: fracture stiffness characteristics and fracture strength characteristics.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method for determining the maximum operating pressure of a gas reservoir type gas storage facility as claimed in any one of claims 1 to 5 is implemented.

10. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the method for determining the maximum operating pressure of a gas reservoir type gas storage facility according to any one of claims 1 to 5 is implemented.

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