A method and apparatus for making a model of a pressurizable fractured reservoir

Abstract

The embodiment of the present application provides a kind of method and device for making pressure-bearing fractured reservoir model, obtain the fracture information and matrix information of target area;According to fracture information, first metal pipe, metal screen and second metal pipe are determined;First metal pipe is used to simulate the model fracture of pressure-bearing fractured reservoir model, and the periphery of first metal pipe includes multiple holes;Metal screen is provided with mesh, and metal screen is wrapped around the first metal pipe;Multiple import and export are provided around the second metal pipe;According to matrix information, model filling material is determined;Model filling material is filled in the second metal pipe, and the first metal pipe wrapped with metal screen is arranged in model filling material, to obtain pressure-bearing fractured reservoir model.The pressure-bearing fractured reservoir model obtained by the method can truly reflect the percolation characteristics and displacement effect of displacement medium under formation conditions.

Description

Technical Field

[0001] This invention relates to the field of petroleum exploration and development, and more specifically to a method and apparatus for creating a pressure-bearing fractured reservoir model. Background Technology

[0002] Fractures in oil reservoirs serve as both storage spaces and seepage channels, significantly impacting their development. To improve the development of fractured reservoirs, it is necessary to clarify the effects of different production parameters, displacement media, fracture numbers, fracture sizes, and fracture plugging degrees on displacement efficiency when fractures coexist with the matrix under reservoir conditions.

[0003] Existing physical models for fractured reservoirs mainly include visualized multi-scale fracture models, matrix core-encased quartz sand fracture models, outcrop core fracture models, and parallel models of metal tubes and matrix cores. Application CN114910391A discloses a visualized multi-level fracture model, which consists of two rectangular glass plates encapsulated with epoxy resin, forming an internal cavity. Within the cavity, a multi-level fracture structure using rock plates to simulate fractures is vertically arranged. An inlet is located on one diagonal side of the cavity, and an outlet is located on the other. This model allows for direct observation of oil-water distribution in multi-level fractures during saturated oil and primary waterflooding processes, but it cannot reflect the relationship between the matrix and fractures, nor can it be used to conduct related experiments under formation pressure. Application CN113404470A discloses a physical model for fractured tight reservoirs. This model simulates the matrix and fractures by encasing a matrix core in quartz sand. The matrix core accurately reflects matrix storage, but the quartz sand cannot reflect the morphology of fractures or control their number and direction. Outcrop core fracture simulation models, due to the prior fracture creation of the core, make it difficult for the matrix core to be saturated with crude oil, thus failing to reflect the impact on matrix displacement. Metal capillary tube and matrix core parallel simulation models use metal capillary tubes to simulate fractures and connect them in parallel with a matrix core equipped with a core holder to simulate the interaction between the matrix and fractures; however, this model cannot effectively reflect the interaction when the matrix and fractures are in direct contact. Summary of the Invention

[0004] The purpose of this invention is to provide a method and apparatus for creating a pressure-bearing fractured reservoir model. The pressure-bearing fractured reservoir model obtained by this method can realistically reflect the seepage characteristics and displacement effect of the displacement medium under formation conditions.

[0005] To achieve the above objectives, embodiments of the present invention provide a method for fabricating a pressure-bearing fractured reservoir model, the method comprising:

[0006] Acquire crack and matrix information for the target area;

[0007] Based on the crack information, a first metal tube, a metal screen, and a second metal tube are determined, with the diameters of the first metal tube, the metal screen, and the second metal tube increasing sequentially.

[0008] The first metal tube is used to simulate the model fractures in a pressure-bearing fractured reservoir model, and the first metal tube is surrounded by multiple holes.

[0009] The metal screen has mesh openings and wraps around the first metal tube to simulate the seepage wall surface of the model crack.

[0010] The second metal tube is provided with multiple inlets and outlets, and the two ends of the second metal tube are fitted with caps, which are provided with cap inlets and outlets to simulate the injection end and extraction end of the model fracture.

[0011] The model filling material is determined based on the matrix information, and the model filling material is used to simulate the matrix part of the pressure-bearing fractured reservoir model;

[0012] The second metal tube is filled with model filling material, and the first metal tube wrapped with a metal screen is placed in the model filling material to obtain a pressure-bearing fractured reservoir model.

[0013] Optionally, acquiring the crack information and matrix information of the target area includes:

[0014] Acquire core data, well logging data, well logging data, seismic data, and geophysical data of the target area;

[0015] The fracture information of the target area is determined based on the core data, well logging data, well logging data, seismic data, and geophysical data.

[0016] Obtain the rock mineral composition, reservoir porosity, and reservoir permeability of the target area;

[0017] The matrix information of the target area is determined based on the rock mineral composition, reservoir porosity, and reservoir permeability data.

[0018] Optionally, determining the first metal tube based on the crack information includes:

[0019] The number, diameter, length, and inclination angle of the first metal tubes in the model crack are determined based on the crack information.

[0020] Optionally, determining the model infill material based on the matrix information includes:

[0021] The type and particle size of the filling material are set according to the matrix information.

[0022] Optionally, the number of holes on the first metal tube is positively correlated with the strength of the first metal tube.

[0023] Optionally, the caps at both ends of the second metal tube are threaded, and the inlet and outlet of the second metal tube are used to connect the interior and exterior of the pressure-bearing fractured reservoir model.

[0024] The holes in the first metal tube, the mesh of the metal screen, and the inlet and outlet of the second metal tube are all used to displace the medium.

[0025] Optionally, the model filling material is sand.

[0026] The mesh size of the metal screen is determined based on the diameter of the sand grains;

[0027] The diameter of the sand particles is smaller than the diameter of the metal screen.

[0028] On the other hand, this application also proposes a method for obtaining oil displacement efficiency, the method comprising:

[0029] A pressure-bearing fractured reservoir model was prepared according to the method described above.

[0030] Crude oil displacement was performed on the confined fractured reservoir model to obtain porosity and oil saturation data of the confined fractured reservoir model;

[0031] Displacement data were obtained by displacing the aforementioned pressure-bearing fractured reservoir model;

[0032] The oil displacement efficiency of the pressure-bearing fractured reservoir model is determined based on the porosity, oil saturation, and displacement data.

[0033] The displacement method is any one or more of water drive, gas drive, and polymer injection drive.

[0034] On the other hand, this application also proposes an apparatus for fabricating a pressure-bearing fractured reservoir model, the apparatus comprising:

[0035] The acquisition module is used to acquire crack and matrix information of the target area;

[0036] A first processing module is used to determine a first metal pipe, a metal screen, and a second metal pipe based on the fracture information, wherein the diameters of the first metal pipe, the metal screen, and the second metal pipe increase sequentially; the first metal pipe is used to simulate the model fractures of a pressure-bearing fractured reservoir model, and the first metal pipe includes multiple holes around its perimeter; the metal screen has mesh openings and wraps around the first metal pipe to simulate the seepage wall of the model fracture; the second metal pipe has multiple inlets and outlets around its perimeter, and both ends of the second metal pipe are fitted with caps, and the caps have cap inlets and outlets to simulate the injection end and production end of the model fracture;

[0037] The second processing module is used to determine the model filling material based on the matrix information, and the model filling material is used to simulate the matrix part of the pressure-bearing fractured reservoir model;

[0038] The third processing module is used to fill the second metal tube with model filling material, and to place the first metal tube wrapped with a metal screen in the model filling material to obtain a pressure-bearing fractured reservoir model.

[0039] On the other hand, the present invention also proposes a machine-readable storage medium storing instructions for causing a machine to perform the method of creating a pressure-bearing fractured reservoir model or the method of obtaining oil displacement efficiency.

[0040] A method for fabricating a pressure-bearing fractured reservoir model according to the present invention includes: acquiring fracture information and matrix information of a target area; determining a first metal pipe, a metal screen, and a second metal pipe based on the fracture information, wherein the diameters of the first metal pipe, the metal screen, and the second metal pipe increase sequentially; the first metal pipe is used to simulate the model fractures of the pressure-bearing fractured reservoir model, and the first metal pipe includes multiple holes around its perimeter; the metal screen has mesh openings and wraps around the first metal pipe to simulate the seepage wall of the model fracture; the second metal pipe has multiple inlets and outlets around its perimeter, and caps are fitted at both ends of the second metal pipe, with cap inlets and outlets on the caps to simulate the injection end and production end of the model fracture; determining a model filling material based on the matrix information, the model filling material being used to simulate the matrix portion of the pressure-bearing fractured reservoir model; filling the second metal pipe with the model filling material, and arranging the first metal pipe wrapped with the metal screen within the model filling material to obtain the pressure-bearing fractured reservoir model. This method uses various parameters of the target area to determine a pressure-bearing fractured reservoir model, which reflects the interaction between the matrix and the fractures and can realistically reflect the seepage characteristics and displacement effect of the displacement medium under formation conditions.

[0041] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0042] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0043] Figure 1 This is a flowchart illustrating a method for creating a pressure-bearing fractured reservoir model according to the present invention.

[0044] Figure 2 This is a top view of the crack in the model of the present invention;

[0045] Figure 3 This is a bottom view of the crack in the model of the present invention;

[0046] Figure 4 This is a left view of the crack in the model of the present invention;

[0047] Figure 5 This is a right view of the crack in the model of the present invention;

[0048] Figure 6 This is a side view of the crack in the model of the present invention;

[0049] Figure 7 This is an internal cross-sectional view of the crack in the model of the present invention;

[0050] Figure 8 This is a schematic diagram of a simulated crack in the model crack of the present invention that is not covered with a metal screen;

[0051] Figure 9 This is a schematic diagram of the metal screen used to wrap the simulated crack metal tube in the model crack of the present invention.

[0052] Figure 10 This is a schematic diagram of the crack in the model crack of the present invention;

[0053] Figure 11 This is a schematic diagram of an apparatus for creating a pressure-bearing fractured reservoir model according to the present invention.

[0054] Explanation of reference numerals in the attached figures

[0055] 1-Model crack; 2-First inlet; 3-First outlet;

[0056] 4 - Second import; 5 - Third import; 6 - Fourth import;

[0057] 7 - Second Exit; 8 - Third Exit; 9 - Fourth Exit;

[0058] 10 - First crack; 11 - Second crack; 12 - Third crack;

[0059] 13-Matrix; 14-Metal tube; 15-Pore;

[0060] 100 - Apparatus for constructing models of pressure-bearing fractured oil reservoirs;

[0061] 200 - Acquisition Module;

[0062] 300 - First Processing Module;

[0063] 400 - Second Processing Module;

[0064] 500 - Third processing module. Detailed Implementation

[0065] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0066] It should be noted that the acquisition, transmission, storage, use, and processing of data in the technical solution of this application all comply with the relevant provisions of national laws and regulations. In the embodiments of this application, certain existing industry solutions such as software, components, and models may be mentioned. These should be considered exemplary, intended only to illustrate the feasibility of implementing the technical solution of this application, and do not imply that the applicant has already used or necessarily used such solutions.

[0067] Example 1

[0068] Figure 1 This is a schematic flowchart of a method for fabricating a pressure-bearing fractured reservoir model according to the present invention, as shown below. Figure 1 As shown, a method for creating a pressure-bearing fractured reservoir model according to the present invention includes:

[0069] Step S101 involves obtaining crack information and matrix information for the target area.

[0070] According to one specific implementation, acquiring fracture information and matrix information of the target area includes: acquiring core data, well logging data, well logging data, seismic data, and geophysical data of the target area; determining fracture information of the target area based on the core data, well logging data, well logging data, seismic data, and geophysical data; acquiring rock mineral composition, reservoir porosity, and reservoir permeability of the target area; and determining matrix information of the target area based on the rock mineral composition, reservoir porosity, and reservoir permeability data.

[0071] The crack information includes crack length, crack width, crack direction, and number of cracks. Specifically, the crack direction includes strike, dip, and inclination angle. The crack length and width include penetration length, extension length, width, distribution density, and spacing. The crack strike refers to the direction along the crack surface, also known as azimuth. The crack dip refers to the direction of inclination of the crack surface. The crack inclination angle refers to the angle between the crack surface and its horizontal projection plane.

[0072] The core data, well logging data, well logging data, seismic data, and geophysical data are the field measurement data and / or historical data of the target area.

[0073] Step S102 involves determining a first metal pipe, a metal screen, and a second metal pipe based on the fracture information, wherein the diameters of the first metal pipe, the metal screen, and the second metal pipe increase sequentially; the first metal pipe is used to simulate the model fractures of a pressure-bearing fractured reservoir model, and the first metal pipe is surrounded by multiple holes; the metal screen has mesh openings and wraps around the first metal pipe to simulate the seepage wall of the model fracture; the second metal pipe is surrounded by multiple inlets and outlets, and both ends of the second metal pipe are fitted with caps, which have cap inlets and outlets to simulate the injection end and production end of the model fracture.

[0074] The number of holes in the first metal tube is positively correlated with the strength of the first metal tube.

[0075] The step of determining the first metal tube based on the crack information includes: determining the number, diameter, length, and inclination angle of the first metal tubes in the model crack based on the crack information. In one specific embodiment, the crack information includes crack length, crack width, crack direction, and number of cracks. The step of determining the model crack based on the crack information includes: setting the size of the model crack based on the crack length and crack width; determining the inclination angle of the model crack based on the crack direction; and determining the number of model cracks based on the number of cracks.

[0076] Specifically, the size of the first metal tube is set according to the crack length and crack width, that is, the size of the first metal tube is the same as the crack length and crack width obtained according to the crack information, and / or the size of the first metal tube is proportionally enlarged or reduced according to the crack length and crack width obtained according to the crack information.

[0077] The tilt angle of the first metal tube is determined based on the crack direction, that is, the angle between the tilt angle of the first metal tube and the crack direction obtained from the crack information and the horizontal projection plane.

[0078] The number of the first metal tubes is determined based on the number of cracks, that is, the number of the first metal tubes is the same as the number of cracks obtained from the crack information, or an adaptive adjustment is made based on the size of the first metal tubes.

[0079] The number of holes on the first metal tube is positively correlated with the strength of its material. Specifically, while ensuring the strength of the first metal tube, as many holes as possible are drilled on it, and a layer of metal mesh with a certain mesh size is wrapped and fixed around the first metal tube and at both ends (the mesh size of the metal mesh must ensure that the model filling material cannot pass through the mesh). This is used to simulate the scale of the cracks in the target area and the seepage capacity of the crack walls. At the same time, the metal tube wrapped with the metal mesh and the holes can be bent into the arc required for the experiment according to the crack morphology requirements.

[0080] Step S103 involves determining the model filling material based on the matrix information. This model filling material is used to simulate the matrix portion of the pressure-bearing fractured reservoir model. The model filling material is sand grains; the mesh size of the metal screen is determined based on the sand grain diameter; the diameter of the sand grains is smaller than the diameter of the metal screen.

[0081] The matrix information is determined based on reservoir permeability, reservoir porosity, reservoir rock mineral composition, and reservoir oil saturation. The model filling material is filled into the pressure-bearing fractured reservoir model to enclose the model fractures.

[0082] According to one specific implementation method, determining the model filling material based on the matrix information includes: setting the type and particle size of the filling material based on the matrix information. Specifically, using sand body genetic analysis and various reservoir microscopic testing methods, combined with mathematical statistics methods, the correspondence between sand body genetic type, pore structure, and permeability is determined. Then, the size of the sand particles is determined based on the reservoir porosity and permeability. Based on the reservoir porosity and permeability, the rock minerals are processed into fine particles of different mesh sizes or sand particles of different mesh sizes are screened.

[0083] Step S104 involves filling the second metal tube with model filling material and placing the first metal tube, which is wrapped with a metal screen, in the model filling material to obtain a pressure-bearing fractured reservoir model.

[0084] According to one specific embodiment, the caps at both ends of the second metal tube are provided with threads, and the inlet and outlet of the second metal tube are used to connect the interior and exterior of the pressure-bearing fractured reservoir model; the holes of the first metal tube, the mesh of the metal screen, and the inlet and outlet of the second metal tube are all used for displacement media.

[0085] The model filling material is sand, and the screen is a metal screen; the mesh size of the screen is determined according to the diameter of the sand grains; the diameter of the sand grains is smaller than the diameter of the screen.

[0086] The method also includes fabricating an outer casing for the pressure-bearing fractured reservoir model. Specifically, based on experimental requirements, the length, diameter, and material of the metal cylindrical tube are selected, and threaded caps with effective sealing are fabricated at both ends of the tube, each cap having an inlet / outlet. Simultaneously, a certain number of inlets and outlets are provided on the tube body, allowing for opening or closing, while meeting the experimental temperature and pressure resistance requirements.

[0087] According to one specific implementation method, assembling the pressure-bearing fractured reservoir model includes: arranging first metal tubes wrapped with metal mesh in an alternating direction and number, and placing the first metal tubes wrapped with metal mesh into second metal tubes according to the fracture dip angle. Then, filling the second metal tubes with fine rock and mineral particles of different mesh sizes (i.e., model filling material).

[0088] The pressure-bearing fractured reservoir model of this invention utilizes a metal circular tube (second metal tube) to combine the model body, including the fractures and the matrix (model filling material), together. The metal circular tube is designed according to reservoir temperature and pressure, and its temperature and pressure resistance meets experimental requirements. Each end of the metal circular tube has an effectively sealed, threaded metal cap with an inlet or outlet. In addition to the inlet and outlet on each cap, a different number of inlets and outlets are designed along the tube body according to its length, allowing for opening and closing.

[0089] The model fractures are designed based on collected core data, well logging data, well logging data, seismic data, geophysical data, tracer monitoring data, and production dynamic analysis data. They are designed in a pressure-bearing fractured reservoir model with reference to the dip angle, scale, and number of fractures in actual oil reservoirs. The design can be customized according to specific experimental requirements.

[0090] The pressure-bearing fractured reservoir model obtained by this method can realistically reflect the seepage characteristics and displacement effect of the displacement medium under formation conditions.

[0091] Example 2

[0092] On the other hand, the present invention also proposes a method for obtaining oil displacement efficiency, the method comprising: preparing a pressure-bearing fractured reservoir model according to the above-described method for preparing a pressure-bearing fractured reservoir model; displacing crude oil in the pressure-bearing fractured reservoir model to obtain porosity and oil saturation data of the pressure-bearing fractured reservoir model; displacing the pressure-bearing fractured reservoir model to obtain displacement data; determining the oil displacement efficiency of the pressure-bearing fractured reservoir model based on the porosity, oil saturation data and displacement data; wherein the displacement method is any one or more of water drive, gas drive and polymer injection. Specifically, it includes one or more experimental contents such as model saturated crude oil, water drive, gas drive, polymer injection, water drive followed by gas drive, plugging agent injection, plugging agent followed by water drive / gas drive, and alternating drive with two or more media.

[0093] Specifically, the method for obtaining oil displacement efficiency includes connecting both ends of the pressure-bearing fractured reservoir model and the inlet and outlet ends of the pipe body to the displacement process, checking the airtightness of the device process, setting the injection and production valves of the device, and performing crude oil displacement from different inlet and outlet ends to ensure that the interior of the pressure-bearing fractured reservoir model is fully saturated with crude oil according to experimental requirements, and recording the porosity and oil saturation data of the model.

[0094] The steps for waterflooding a pressure-bearing fractured reservoir model include: connecting the inlet and outlet ends of the pressure-bearing fractured reservoir model saturated with good crude oil to the displacement process; checking the airtightness of the process flow; setting the injection and production valves; setting the back pressure at the outlet end; placing the pressure-bearing fractured reservoir model in an oven at a certain temperature; waterflooding until the water saturation at the outlet end reaches 99% or higher; recording the pressure at the inlet and outlet ends, the injection and discharge rate at the inlet end, the oil production and water production at the outlet end at different time periods, and the cumulative oil production and water production; and calculating the waterflooding efficiency.

[0095] The steps for gas drive in a pressure-bearing fractured reservoir model include: connecting the inlet and outlet ends of the pressure-bearing fractured reservoir model saturated with good crude oil to the displacement process; checking the airtightness of the process flow; setting the injection and production valves; setting the back pressure at the outlet; placing the pressure-bearing fractured reservoir model in an oven at a certain temperature; driving the gas drive until the gas production rate at the outlet reaches 100%; recording the pressure at the inlet and outlet ends, the injection and discharge rate at the inlet end, the oil production rate at the outlet end at different time periods, the cumulative oil production rate, and the gas production rate; and calculating the gas drive oil displacement efficiency.

[0096] The steps for polymer flooding using a pressure-bearing fractured reservoir model include: connecting the inlet and outlet ends of the pressure-bearing fractured reservoir model saturated with good crude oil to the displacement process; checking the airtightness of the process flow; setting the injection and production valves; setting the back pressure at the outlet end; placing the pressure-bearing fractured reservoir model in an oven at a certain temperature; injecting polymer flooding until the polymer content at the outlet end reaches more than 99%; recording the pressure at the inlet and outlet ends, the injection displacement at the inlet end, the oil production at the outlet end at different time periods, the polymer production, and the cumulative oil production and polymer production; and calculating the polymer flooding efficiency.

[0097] The steps for waterflooding followed by gasflooding of a confined fractured reservoir model include: connecting the inlet and outlet ends of the confined fractured reservoir model to the displacement process, checking the airtightness of the process flow, setting the injection and production valves, setting the back pressure at the outlet end, placing the confined fractured reservoir model in an oven at a certain temperature, waterflooding until the water saturation at the outlet end reaches 99% or higher, and then switching to gasflooding. Record the pressure at the inlet and outlet ends, the injection and discharge rate at the inlet end, the oil production, water production, and gas production at the outlet end at different time periods, and the cumulative oil production, water production, and gas production. Calculate the waterflooding efficiency and the gasflooding efficiency after waterflooding.

[0098] The steps for plugging a pressureless fractured reservoir model with plugging agent followed by waterflooding include: connecting the inlet and outlet ends of the pressureless fractured reservoir model saturated with good crude oil to the displacement process; checking the airtightness of the process flow; setting the injection and production valve switches; setting the back pressure at the outlet end; placing the pressureless fractured reservoir model in an oven at a certain temperature; waterflooding until the water saturation at the outlet end reaches 99% or higher; then injecting plugging agent; after the plugging agent injection is completed, closing the inlet and outlet ends of the pressureless fractured reservoir model; placing the pressureless fractured reservoir model at the formation temperature to allow the plugging agent to fully gel; then connecting the pressureless fractured reservoir model to the displacement process for plugging followed by waterflooding; recording the inlet and outlet pressures, inlet injection displacement, oil production and water production at different time periods at different displacement stages, and the cumulative oil production and water production; and calculating the waterflooding efficiency and the waterflooding efficiency after plugging agent.

[0099] The pressure-bearing fractured reservoir model can not only conduct experiments under formation temperature and pressure to better simulate the real formation conditions, but also simulate the seepage process of injected fluid in fractured reservoirs on fracture walls with different permeability, as well as the interaction process between fractures and matrix in fractured reservoirs, effectively solving the problem of matrix crude oil saturation difficulties when fractures and matrix coexist.

[0100] This invention designs different fracture sizes, numbers, and tortuosities based on different reservoir conditions. It can simulate the effects of fracture wall seepage capacity, fracture size, number of fractures, fracture morphology, fracture direction, and displacement medium type on the displacement effect when the matrix and fractures coexist in fractured reservoirs. It can also simulate the effects of injection parameters such as injection pressure and injection volume on the migration law of plugging agent, as well as the effects of different sealing positions and sealing lengths of fractures on the displacement effect, providing a more accurate basis for the development of fractured reservoirs.

[0101] Example 3

[0102] Figure 2 This is a top view of the crack in the model of the present invention. Figure 3 This is a bottom view of the crack in the model of the present invention. Figure 4 This is a left view of the crack in the model of the present invention. Figure 5 This is a right view of the crack in the model of the present invention. Figure 6 This is a side view of the crack in the model of the present invention. Figure 7 This is an internal cross-sectional view of the crack in the model of the present invention, as shown below. Figures 2-7 As shown ( Figure 7 The shaded area represents the filling matrix 13 (i.e., the model filling material). In this embodiment, the model fracture 1 of the pressure-bearing fractured reservoir model is a cylindrical model. The entire model is divided into a first inlet 2, a first outlet 3, a second inlet 4, a third inlet 5, a fourth inlet 6, a second outlet 7, a third outlet 8, and a fourth outlet 9 from the outside to the inside. The matrix 13 (i.e., the model filling material) has a permeability of 51 mD. The first fracture 10 has a diameter of 2 mm and a length of 20 cm and is wrapped with a 0.05 mm sieve. The second fracture 11 has a diameter of 2 mm and a length of 25 cm and is wrapped with a 0.03 mm sieve. The third fracture 12 has a diameter of 1 mm and a length of 25 cm and is wrapped with a 0.03 mm sieve.

[0103] The present invention relates to a method for fabricating a physical model of a fractured reservoir as described above, comprising three steps: structural analysis of the fractured reservoir, design of the fracture physical model, and fabrication of the fracture physical model.

[0104] 1. Structural analysis of the fractured reservoir: Based on well logging data, core data, and seismic data collected in the reservoir field, the characteristics of fractures and matrix were analyzed. This included extensive core observation and field outcrop studies. The analysis showed that the width of the fractures was 1-2 mm, the dip angle of the fractures was between 0° and 50°, and the average permeability of the matrix was 50 mD.

[0105] 2. Dynamic analysis of the fractured reservoir: Based on the monitoring results of the tracer between oil and water wells and the dynamic response results between oil and water wells, the tracer between oil and water wells was detected in 4 days. The water injection wells with a cumulative water injection of 136 m3 and a cumulative water injection of 5 days showed water channeling characteristics, with the dynamic fluid level rising by 200 m, chloride ion decreasing by 40%, water cut rising to 100%, and daily production increasing by 54%, exhibiting the characteristics of water channeling in straight fractures.

[0106] 3. Design of the pressure-bearing fractured reservoir model: The design comprehensively considers experimental requirements, ease of fabrication, pressure bearing capacity, and simulation accuracy. This includes the design of the main exterior and internal structure of the physical model of the fractured reservoir. The model's exterior design is a metal cylindrical tube with a diameter of 25cm and a length of 60cm. Three inlets and three outlets are designed at positions 15cm, 30cm, and 45cm from the ends and the middle, respectively. Figures 2-7 As shown), two matching metal caps with threaded fasteners are designed at both ends of the cylinder, each cap having a first inlet 2 or a first outlet 3; the matrix is ​​designed as 160-200 mesh rock fragment powder; the cracks are designed as metal tubes 14 with holes 15, each with a diameter of 2mm, a length of 35cm, and wrapped with a 0.05mm mesh screen; metal tubes 14 with holes 15, each with a diameter of 2mm, a length of 45cm, and wrapped with a 0.03mm mesh screen screen; and metal tubes 14 with holes 15, each with a diameter of 1mm, a length of 45cm, and wrapped with a 0.03mm mesh screen screen screen. The inclination angles of the cracks are designed as two 0° (first crack 10 and second crack 11, respectively) and one 50° (third crack 12).

[0107] 4. Fabrication of the physical model for the pressure-bearing fractured reservoir: Based on the physical model of the fractured reservoir designed in the above steps, one end of a cylindrical metal tube is sealed with a cap, and rock cuttings powder is filled into the tube from the other end, such as... Figures 8-10 As shown, a metal tube with a metal screen is placed inside a cylindrical tube at the required angle and filled with rock fragments.

[0108] Example 4

[0109] This invention relates to an experimental method for a fractured reservoir model, comprising five steps: model saturation with water, model saturation with oil, simulated reservoir waterflooding development, simulated reservoir injection of profile control agent, and simulated reservoir waterflooding after injection of profile control agent.

[0110] 1. The model saturated water comprises: preparing simulated formation water, weighing the dried model, placing the model in a constant temperature oven to heat to the formation temperature, connecting pipelines to check the airtightness of the device, setting the back pressure to the formation pressure, and injecting simulated formation water into the model (through the first inlet 2, the first outlet 3, the second inlet 4, the third inlet 5, the fourth inlet 6, the second outlet 7, the third outlet 8, and the fourth outlet 9, respectively). After the flow rate at each outlet has been stable for a long period, the pump is stopped, the model is removed, weighed, the volume of saturated water in the model is calculated, and the pressure data is recorded. The formation water is prepared based on the average salinity of the formation water in the actual oil reservoir, and the content of each salt per liter of formation water is obtained through a formation water simulation preparation program.

[0111] 2. The model saturated oil comprises: a simulated oil prepared by mixing kerosene and crude oil in a certain proportion with a viscosity consistent with that of the formation crude oil; placing the model in a constant temperature oven to heat it to the formation temperature; connecting pipelines to check the airtightness of the device; setting the back pressure to the formation pressure; and injecting the simulated oil into the model (through the first inlet 2, the first outlet 3, the second inlet 4, the third inlet 5, the fourth inlet 6, the second outlet 7, the third outlet 8, and the fourth outlet 9, respectively). After only oil and no water are discharged from each outlet, the pump is stopped, and the volume of the saturated crude oil is calculated based on the amount of water discharged, and the pressure data is recorded.

[0112] 3. The steps of the simulated reservoir waterflooding development include connecting the experimental device, placing the model in a constant temperature oven to heat to the formation temperature, connecting pipelines to check the airtightness of the device, setting the back pressure to the formation pressure, setting the injection flow rate of the simulated waterflooding, displacing (first inlet 2 in, first outlet 3 out, other inlets and outlets closed) until the water content at the outlet end is 100%, then stopping the pump, calculating the waterflooding recovery rate and recording the pressure data. The water used for waterflooding is prepared according to the injection water salinity of the actual reservoir.

[0113] 4. The steps of injecting profile control agent into the simulated reservoir include preparing the profile control agent, connecting the experimental device, setting the injection flow rate of the profile control agent, injecting a certain volume of profile control agent (first inlet 2 in, first outlet 3 out, other inlets and outlets closed) and recording pressure data, closing all inlet and outlet valves and placing the model injected with the profile control agent in an oven at formation temperature to wait for the plugging agent to completely gel.

[0114] 5. The steps of injecting profile control agent into the simulated reservoir and then waterflooding include connecting the experimental device, placing the model in a constant temperature oven to heat it to the formation temperature, connecting the pipeline to check the airtightness of the device, setting the back pressure to the formation pressure, setting the injection flow rate of the simulated waterflooding, displacement (first inlet 2 in, first outlet 3 out, other inlets and outlets closed), stopping the pump after the water content at the outlet end reaches 100%, calculating the waterflooding recovery rate after profile control and recording the pressure data.

[0115] Following the above steps, the simulated formation water salinity was 67140 mg / L; the injected water salinity was 794 mg / L; the formation pressure was 13 MPa, and the back pressure design was 13 MPa; the simulated oil used was a mixture of formation crude oil and kerosene in a 4:1 ratio, and the viscosity of the simulated oil at 69℃ (formation temperature) was 3.4 mPa·s; the profile control agent used was phenolic resin plugging agent, and the injection volumes of the plugging agent were 0.1, 0.2, 0.3, 0.4, and 0.5 PV (as shown in Tables 1, 2, and 3).

[0116] Table 1: Mass of each substance in the formation water and injected water used in the experimental case

[0117]

[0118] Table 2: Pressure Changes Before and After Profile Adjustment Using the Fractured Reservoir Physical Model in the Experimental Case

[0119]

[0120] Table 3: Final recovery rate results before and after profile modification using the physical model of fractured reservoirs in the experimental case.

[0121]

[0122] Based on the waterflooding experimental results before and after profile modification in the fractured reservoir model in the experimental examples (as shown in Tables 1, 2, and 3), profile modification has a significant sealing effect on fractures, effectively improving the waterflooding development effect of fractured reservoirs. Furthermore, the larger the injection volume of profile modification agent, the better the sealing effect on fractures, and the more beneficial it is to improving the waterflooding development effect. This fractured reservoir model can simulate fractures of different scales, tortuosities, and directions, better reflecting the true morphology of fractures in the formation. It can also conduct experiments under high temperature and high pressure, reflecting the interaction process between fractures and matrix under real formation conditions. Moreover, it can meet the overall saturation requirements of crude oil and saturated water when fractures and matrix coexist and have a direct interaction relationship.

[0123] Example 5

[0124] On the other hand, such as Figure 11As shown, the present invention also proposes an apparatus for fabricating a pressure-bearing fractured reservoir model. The apparatus 100 includes: an acquisition module 200 for acquiring fracture information, fracture connectivity, reservoir porosity, and reservoir permeability of a target area; a first processing module 300 for determining model fractures based on the fracture information, wherein the model fractures include multiple pores for oil, water, or gas production; a second processing module 400 for determining model filling material based on the reservoir porosity and reservoir permeability; and a third processing module 500 for obtaining a pressure-bearing fractured reservoir model using the model filling material based on the fracture connectivity and model fractures.

[0125] According to a specific implementation, acquiring fracture information in the target area includes: acquiring core data, well logging data, well logging data, seismic data, and geophysical data of the target area; and determining fracture information of the target area based on the core data, well logging data, well logging data, seismic data, and geophysical data. The fracture information includes fracture length, fracture width, fracture direction, and number of fractures. Determining model fractures based on the fracture information includes: setting the size of the model fractures based on the fracture length and fracture width; determining the dip angle of the model fractures based on the fracture direction; and determining the number of model fractures based on the number of fractures. The fracture connectivity includes straight-through fracture connectivity and non-straight-through fracture connectivity; straight-through fracture connectivity is when two adjacent fractures are connected in a straight line; non-straight-through fracture connectivity is when two adjacent fractures are not connected in a straight line. The model fractures are metal pipes; the number of pores in the model fractures is positively correlated with the strength of the metal pipe. This device uses various parameters of the target area to determine a pressure-bearing fractured reservoir model, reflecting the interaction between the matrix and fractures, and can realistically reflect the seepage characteristics and displacement effect of the displacement medium under formation conditions.

[0126] A method for fabricating a pressure-bearing fractured reservoir model according to the present invention includes: acquiring fracture information and matrix information of a target area; determining a first metal pipe, a metal screen, and a second metal pipe based on the fracture information, wherein the diameters of the first metal pipe, the metal screen, and the second metal pipe increase sequentially; the first metal pipe is used to simulate the model fractures of the pressure-bearing fractured reservoir model, and the first metal pipe includes multiple holes around its perimeter; the metal screen has mesh openings and wraps around the first metal pipe to simulate the seepage wall of the model fracture; the second metal pipe has multiple inlets and outlets around its perimeter, and caps are fitted at both ends of the second metal pipe, with cap inlets and outlets on the caps to simulate the injection end and production end of the model fracture; determining a model filling material based on the matrix information, the model filling material being used to simulate the matrix portion of the pressure-bearing fractured reservoir model; filling the second metal pipe with the model filling material, and arranging the first metal pipe wrapped with the metal screen within the model filling material to obtain the pressure-bearing fractured reservoir model. This method uses various parameters of the target area to determine a pressure-bearing fractured reservoir model, which reflects the interaction between the matrix and the fractures and can realistically reflect the seepage characteristics and displacement effect of the displacement medium under formation conditions.

[0127] On the other hand, embodiments of the present invention provide a storage medium on which a program is stored, which, when executed by a processor, implements the method for creating a pressure-bearing fractured reservoir model.

[0128] This invention provides a processor for running a program, wherein the program executes the method for creating a pressure-bearing fractured reservoir model.

[0129] This invention provides a device comprising a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, it performs the following steps: acquiring fracture information and matrix information of a target area; determining a first metal pipe, a metal screen, and a second metal pipe based on the fracture information, wherein the diameters of the first metal pipe, the metal screen, and the second metal pipe increase sequentially; the first metal pipe is used to simulate the model fractures of a pressure-bearing fractured reservoir model, and the first metal pipe is surrounded by multiple holes; the metal screen has mesh openings and wraps around the first metal pipe to simulate the seepage wall of the model fracture; the second metal pipe has multiple inlets and outlets around it, and both ends of the second metal pipe are fitted with caps, the caps having cap inlets and outlets to simulate the injection and production ends of the model fracture; determining a model filling material based on the matrix information, the model filling material being used to simulate the matrix portion of the pressure-bearing fractured reservoir model; filling the second metal pipe with the model filling material, and placing the first metal pipe wrapped with the metal screen within the model filling material to obtain a pressure-bearing fractured reservoir model. The device described herein can be a server, PC, PAD, mobile phone, etc.

[0130] This application also provides a computer program product, which, when executed on a data processing device, is suitable for executing an initialization program with the following method steps: acquiring fracture information and matrix information of a target area; determining a first metal pipe, a metal screen, and a second metal pipe based on the fracture information, wherein the diameters of the first metal pipe, the metal screen, and the second metal pipe increase sequentially; the first metal pipe is used to simulate the model fractures of a pressure-bearing fractured reservoir model, and the first metal pipe includes multiple holes around its perimeter; the metal screen has mesh openings and wraps around the first metal pipe to simulate the seepage wall of the model fracture; the second metal pipe has multiple inlets and outlets around its perimeter, and both ends of the second metal pipe are fitted with caps, the caps having cap inlets and outlets to simulate the injection end and production end of the model fracture; determining a model filling material based on the matrix information, the model filling material being used to simulate the matrix portion of the pressure-bearing fractured reservoir model; filling the second metal pipe with the model filling material, and arranging the first metal pipe wrapped with the metal screen within the model filling material to obtain a pressure-bearing fractured reservoir model.

[0131] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0132] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0133] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0134] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0135] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0136] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0137] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0138] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0139] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for fabricating a pressure-bearing fractured reservoir model, characterized in that, The method includes: Acquire crack and matrix information for the target area; Based on the crack information, a first metal tube, a metal screen, and a second metal tube are determined, with the diameters of the first metal tube, the metal screen, and the second metal tube increasing sequentially. The first metal tube is used to simulate the model fractures in a pressure-bearing fractured reservoir model, and the first metal tube is surrounded by multiple holes. The metal screen has mesh openings and wraps around the first metal tube to simulate the seepage wall surface of the model crack. The second metal tube is provided with multiple inlets and outlets, and the two ends of the second metal tube are fitted with caps, which are provided with cap inlets and outlets to simulate the injection end and extraction end of the model fracture. The model filling material is determined based on the matrix information, and the model filling material is used to simulate the matrix part of the pressure-bearing fractured reservoir model; The second metal tube is filled with model filling material, and the first metal tube wrapped with a metal screen is placed in the model filling material to obtain a pressure-bearing fractured reservoir model.

2. The method according to claim 1, characterized in that, The acquisition of crack information and matrix information of the target area includes: Acquire core data, well logging data, well logging data, seismic data, and geophysical data of the target area; The fracture information of the target area is determined based on the core data, well logging data, well logging data, seismic data, and geophysical data. Obtain the rock mineral composition, reservoir porosity, and reservoir permeability of the target area; The matrix information of the target area is determined based on the rock mineral composition, reservoir porosity, and reservoir permeability data.

3. The method according to claim 1, characterized in that, The step of determining the first metal tube based on the crack information includes: The number, diameter, length, and inclination angle of the first metal tubes in the model crack are determined based on the crack information.

4. The method according to claim 1, characterized in that, The step of determining the model filling material based on the matrix information includes: The type and particle size of the filling material are set according to the matrix information.

5. The method according to claim 1, characterized in that, The number of holes in the first metal tube is positively correlated with the strength of the first metal tube.

6. The method according to claim 1, characterized in that, The caps at both ends of the second metal tube are threaded, and the inlet and outlet of the second metal tube are used to connect the inside and outside of the pressure-bearing fractured reservoir model. The holes in the first metal tube, the mesh of the metal screen, and the inlet and outlet of the second metal tube are all used to displace the medium.

7. The method according to claim 1, characterized in that, The model filling material is sand. The mesh size of the metal screen is determined based on the diameter of the sand grains; The diameter of the sand particles is smaller than the diameter of the metal screen.

8. A method for obtaining oil displacement efficiency, characterized in that, The method includes: A pressure-bearing fractured reservoir model is prepared according to any one of claims 1 to 7 above. Crude oil displacement was performed on the confined fractured reservoir model to obtain porosity and oil saturation data of the confined fractured reservoir model; Displacement data were obtained by displacing the aforementioned pressure-bearing fractured reservoir model; The oil displacement efficiency of the pressure-bearing fractured reservoir model is determined based on the porosity, oil saturation, and displacement data. The displacement method is any one or more of water drive, gas drive, and polymer injection drive.

9. An apparatus for fabricating a pressure-bearing fractured reservoir model, characterized in that, The device includes: The acquisition module is used to acquire crack and matrix information of the target area; A first processing module is used to determine a first metal pipe, a metal screen, and a second metal pipe based on the fracture information, wherein the diameters of the first metal pipe, the metal screen, and the second metal pipe increase sequentially; the first metal pipe is used to simulate the model fractures of a pressure-bearing fractured reservoir model, and the first metal pipe includes multiple holes around its perimeter; the metal screen has mesh openings and wraps around the first metal pipe to simulate the seepage wall of the model fracture; the second metal pipe has multiple inlets and outlets around its perimeter, and both ends of the second metal pipe are fitted with caps, and the caps have cap inlets and outlets to simulate the injection end and production end of the model fracture; The second processing module is used to determine the model filling material based on the matrix information, and the model filling material is used to simulate the matrix part of the pressure-bearing fractured reservoir model; The third processing module is used to fill the second metal tube with model filling material, and to place the first metal tube wrapped with a metal screen in the model filling material to obtain a pressure-bearing fractured reservoir model.

10. A machine-readable storage medium storing instructions thereon, characterized in that, This instruction is used to cause the machine to perform the method of creating a pressure-bearing fractured reservoir model as described in any one of claims 1-7 or the method of obtaining oil displacement efficiency as described in claim 8.

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