Water-drive reservoir carbon dioxide injection oil displacement simulation device and simulation method

Abstract

The invention discloses a water drive reservoir carbon dioxide injection oil displacement simulation device. The device comprises a square box body used for bearing a simulation stratum sand body, a compaction assembly located above the square box body and used for compacting and shaping the simulation stratum sand body, and a simulation shaft embedded in the simulation stratum sand body. By arranging the compaction assembly, simulation of stratums with different thicknesses and heights can be achieved, so that the stratum condition is more truly restored, meanwhile, the position of a well position is truly restored, experimenters can conveniently observe and adjust the injection-production relation, the experiment result is more close to the real oil field condition, and the experiment efficiency is improved. The method is of great significance to adjustment of a water-drive reservoir carbon dioxide injection oil displacement strategy.

Description

Technical Field

[0001] The invention relates to the technical field of oil production engineering, and in particular to a water-driven oil reservoir carbon dioxide injection oil recovery simulation device and a simulation method. Background Art

[0002] Water injection is an important way to develop oil reservoirs in my country. The water-driven recovery rate of onshore oil fields in my country is about 30-40%. After water-driven oil, there is still a large amount of residual oil remaining in the reservoir. How to further improve the recovery rate of water-driven oil fields has become a hot research direction.

[0003] Carbon dioxide flooding technology is a technology that injects carbon dioxide into oil layers to increase the oil recovery rate of oil fields. Carbon dioxide flooding can greatly increase crude oil recovery and effectively realize the geological storage of carbon dioxide. Carbon dioxide flooding has been widely used abroad, but less used in China. Through a large number of domestic and foreign literature surveys, it is believed that as a new energy supplement method, after carbon dioxide is injected into the formation, some physical and chemical effects are produced, which can improve the development effect of ultra-low permeability oil reservoirs, and it is necessary to conduct in-depth research.

[0004] At present, the indoor carbon dioxide flooding simulation device is generally a core displacement or a displacement simulation of the entire formation. For example, patent CN116122805A provides a carbon dioxide flooding and storage simulation device and method, including a formation model, a pressure chamber, a carbon dioxide container assembly, a back pressure element and a monitoring assembly. The formation model is used to be set in the pressure chamber, and the formation model has pores; the pressure chamber is used to maintain a first preset pressure; the carbon dioxide container assembly is used to introduce the configured supercritical carbon dioxide conductive fluid into the formation model; the back pressure element is connected to the formation model, and when the pressure of the formation model pores reaches the second preset pressure, the back pressure element is turned on, and the monitoring assembly is at least used to monitor the pressure and conductivity changes inside the formation model during the supercritical carbon dioxide conductive fluid flooding and storage process. It can simulate the carbon dioxide flooding and storage process, and dynamically monitor the process. However, this type of device cannot simulate the process of well soaking and carbon dioxide huff and puff during carbon dioxide flooding. Summary of the invention

[0005] In view of the above problems, the present invention provides a simulation device and method for water-driven oil reservoir carbon dioxide injection flooding.

[0006] The technical solution of the present invention is: A water-driven oil reservoir carbon dioxide injection flooding simulation device comprises a square box for carrying a simulated formation sand body, a compaction assembly located above the square box for compacting and shaping the simulated formation sand body, and a simulated wellbore embedded in the simulated formation sand body; The compacting assembly includes columns located in the middle of the four sides of the square box body, each of the columns is fixedly connected to a cross slide on the top, a slide slot is provided in the middle of the cross slide, a lifting motor that slides along the slide slot is provided on the top of the cross slide, an output end of the lifting motor passes through the slide slot and an electric shaft is provided at the rear end, a connecting rod is provided at the bottom output end of the electric shaft, a plurality of compacting motors are arranged at equal intervals at the bottom of the connecting rod, a lifting rod is provided at the bottom of each compacting motor, a shaping column is provided at the bottom of the lifting rod, and a pressing plate is detachably provided at the bottom of the shaping column; The simulated wellbore is provided with a plurality of seepage holes at equal intervals.

[0007] Furthermore, push rod motors are provided on the tops of two adjacent columns, and the output shafts of the push rod motors are detachably connected to the lifting motors.

[0008] Furthermore, a first T-shaped groove is provided on one side of the end of the output shaft of the push rod motor, a U-shaped block is provided inside the first groove, a spring is provided at the bottom of the U-shaped block, and the spring is connected to the bottom of the first groove. A second groove is provided on each side of the outer shell of the lifting motor corresponding to the two push rod motors, the output shaft of the push rod motor extends into the inside of the second groove and is slidably connected to the second groove, and the end of the U-shaped block pops up and engages with the limit groove provided at the top of the second groove.

[0009] Note: The U-shaped block is provided to facilitate quick disassembly and installation of the output shaft of the push rod motor and the housing of the lifting motor.

[0010] Furthermore, the number of shaping columns is 6 to 8.

[0011] Furthermore, the lifting motor, the push rod motor and each of the compacting motors are all equipped with a built-in PLC controller, and the PLC controller is connected to an external control system.

[0012] Furthermore, a T-shaped block is provided on the top of the pressure plate, and a T-shaped slot is provided on the bottom of each shaping column, and the T-shaped block is clamped with the T-shaped slot located in a straight line.

[0013] Furthermore, a detachable pressing block which is slidably fitted with the inner wall of the square box is provided inside the square box for compacting the simulated stratum sand body, and a heater is provided on each side of the square box.

[0014] The present invention also provides a method for simulating oil recovery by injecting carbon dioxide into a water-driven oil reservoir, based on a device for simulating oil recovery by injecting carbon dioxide into a water-driven oil reservoir as described in any one of the above, comprising the following steps: S1. Small layer structure simulation: S1-1: X-axis trend simulation: Add simulated formation sand body into the square box, then shape the simulated formation sand body through the compaction component, move the lifting motor of the compaction component to one side of the cross slide through the push rod motor, keep each shaping column at the same horizontal line and install a pressure plate at the bottom of each shaping column, turn on the lifting motor to lower the shaping column, use the pressure plate to compact the edge of the simulated formation sand body, then raise the shaping column, remove the pressure plate, and lower the shaping column to the surface of the simulated formation sand body again, turn on the push rod motor to push the lifting motor to slide along the slide groove while driving the shaping column to slide along the surface of the simulated formation sand body, and at the same time, according to the pre-set elevation map of the small layer, turn on each compaction motor while moving the shaping column, drive the shaping column to slide up and down during movement to highly shape the simulated formation sand body until the shaping column moves to the edge of the square box, then compact the simulated formation sand body on this side, reverse the direction to highly shape again, repeat several times, and complete the X-axis trend simulation of the simulated formation sand body of the small layer; S1-2, Y-axis trend simulation: reset the compaction assembly, move the lifting motor to the middle of the cross slide through the push rod motor, release the connection between the push rod motor and the lifting motor, then dock the output shaft of another push rod motor with the lifting motor, turn on the electric shaft to drive the connecting rod to rotate 90°, then move the lifting motor to one side of the cross slide through the push rod motor, and then use the same compaction and height shaping method as in step S1-1 to complete the Y-axis trend simulation of the small layer simulated formation sand body; S2, oil layer structure simulation: after completing the trend simulation of several small layers of simulated formation sand bodies according to the method in step S1, the oil layer structure simulation is performed. After completing the trend simulation of the simulated formation sand body for the small layer as the oil layer, simulated formation oil is poured on the surface of the simulated formation sand body. After standing for 15-20 minutes, the trend simulation of the next small layer of simulated formation sand body can be performed; S3, stratigraphic structure simulation: after completing the trend simulation of the simulated stratigraphic sand bodies of all sub-layers and oil layers according to the methods in steps S1 and S2, the simulated surface sand body is covered on the last sub-layer to complete the stratigraphic structure simulation; S4. Well location layout: 1 to 3 simulated oil production wells are arranged at any position in the formation structure, and 3 to 6 simulated water injection wells are arranged around the oil production wells. The seepage holes at the positions of the simulated wellbores corresponding to the oil layers are opened, and then the simulated wellbores are inserted into the corresponding well locations, with the top positions of the simulated wellbores being the same; S5, pressurization and compaction: add simulated surface sand again, so that the simulated surface sand is 3-5 cm above the top of each simulated wellbore, mark the top position of each simulated wellbore, then place the pressing block on the simulated surface sand, reset the compaction assembly, move the lifting motor to the middle of the cross slide through the push rod motor, keep each shaping column at the same horizontal line and install a pressing plate at the bottom of each shaping column, turn on the lifting motor to lower the shaping column, use the pressing plate to press the pressing block downward to pressurize and compact the entire simulated stratum structure, and heat the simulated stratum structure through a heater, the heating temperature is 85-90°C, the pressurization and compaction pressure is 15-20MPa, and the pressurization and compaction time is 12-24h; S6, simulated water injection: inject water into the simulated wellbore at the simulated water injection well location to displace the simulated formation oil in the oil layer, and produce it from the simulated wellbore at the simulated oil production well location, and record the recovery rate; S7. Simulate carbon dioxide injection and puff: inject carbon dioxide into the simulated wellbore of the simulated water injection well location for 10-12 hours, stop injection for 5-6 hours, repeat 3-5 times, displace the simulated formation oil in the oil layer, and produce it from the simulated wellbore of the simulated oil production well location, and record the recovery rate.

[0015] Furthermore, the number of repetitions in step S1-1 is 2 to 3 times, the number of repetitions in step S1-2 is 2 to 3 times, the particle size of the simulated formation sand body is 0.05 to 0.1 μm, and the particle size of the simulated surface sand body is 0.5 to 1 μm.

[0016] The beneficial effects of the present invention are: A water-drive oil reservoir carbon dioxide injection flooding simulation device of the present invention can achieve the simulation of strata of different thickness and height through the setting of the compaction component, so as to more realistically restore the strata situation, and at the same time realistically restore the location of the well, so as to facilitate the experimenter to observe and adjust the injection-production relationship, and the experimental results are closer to the actual oil field situation, which is of great significance for the adjustment of the water-drive oil reservoir carbon dioxide injection flooding strategy. A water-drive oil reservoir carbon dioxide injection flooding simulation device of the present invention uses a shaping column with adjustable height to shape the sand body in turn from the X-axis and the Y-axis, so as to more realistically simulate the thickness and trend of the small layer, and has a stronger three-dimensional sense. It is an unprecedented attempt in the current oil field flooding indoor simulation experimental device, and also provides theoretical support for the subsequent water-drive oil reservoir carbon dioxide injection flooding. A water-drive oil reservoir carbon dioxide injection flooding simulation method of the present invention is based on the device of the present invention, and provides a detailed operation method, mainly optimizes the simulation details of the small layer X-axis and Y-axis, and optimizes the layout of the subsequent simulation wellbore, so that the installation of the simulation wellbore is more in line with the actual drilling situation, and finally can more accurately simulate the water-drive oil reservoir carbon dioxide injection flooding result. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1It is a schematic diagram of the overall structure of a water-driven oil reservoir carbon dioxide injection oil recovery simulation device of the present invention; Figure 2 It is a top view of a simulation device for injecting carbon dioxide into a water-driven oil reservoir according to the present invention; Figure 3 It is a schematic diagram of the shaping column structure of a water-driven oil reservoir carbon dioxide injection oil flooding simulation device of the present invention; Figure 4 It is a front view of a compaction component of a water-driven oil reservoir carbon dioxide injection oil recovery simulation device of the present invention; Figure 5 It is a front view of a compaction component of a water-flooding oil reservoir carbon dioxide injection oil flooding simulation device of the present invention when performing structural simulation; Figure 6 It is a structural schematic diagram of the connection between the output end of the push rod motor and the housing of the lifting motor of a water-driven oil reservoir carbon dioxide injection oil flooding simulation device of the present invention; Figure 7 It is a structural schematic diagram of a water-flooding reservoir carbon dioxide injection flooding simulation device of the present invention when a U-shaped block is pressed at the connection between the push rod motor output end and the lifting motor housing; Figure 8 It is a schematic diagram of the interior of a square box after S3 formation structure simulation of a water drive oil reservoir carbon dioxide injection oil recovery simulation method of the present invention; Fig. 9 It is a schematic diagram of the interior of a square box after the S4 well position is arranged in a water drive oil reservoir carbon dioxide injection oil recovery simulation method of the present invention; Fig.10 It is a top view of the internal structure of a square box after the S4 well position is arranged in a water drive oil reservoir carbon dioxide injection oil recovery simulation method of the present invention.

[0017] Among them, 1-square box, 11-pressing block, 12-heater, 2-compacting assembly, 21-column, 22-cross slide, 23-slide, 24-lifting motor, 241-second groove, 242-limiting groove, 25-electric shaft, 26-connecting rod, 27-compacting motor, 28-lifting rod, 3-simulated wellbore, 31-seepage hole, 4-shaping column, 41-T-slot, 5-pressing plate, 51-T-block, 6-push rod motor, 61-first groove, 62-U-block, 63-spring. DETAILED DESCRIPTION

[0018] Example 1 like Figure 1~2As shown, a water-flooding reservoir carbon dioxide injection flooding simulation device is characterized in that it includes a square box 1 for carrying a simulated formation sand body, a compaction component 2 located above the square box 1 for compacting and shaping the simulated formation sand body, a simulated wellbore 3 embedded in the simulated formation sand body, a detachable pressing block 11 that fits and slides with the inner wall of the square box 1, and is used to compact the simulated formation sand body, and a heater 12 is provided on each side of the square box 1; like Figures 3-5 As shown, the compaction assembly 2 includes a column 21 located in the middle of the four sides of the square box body 1, and each column 21 is fixedly connected to a cross slide 22 on the top, and a slide slot 23 is provided in the middle of the cross slide 22. A lifting motor 24 sliding along the slide slot 23 is provided on the upper part of the cross slide 22, and an electric shaft 25 is provided at the rear end after the output end of the lifting motor 24 passes through the slide slot 23, and a connecting rod 26 is provided at the bottom output end of the electric shaft 25, and 6 compaction motors 27 are arranged at equal intervals at the bottom of the connecting rod 26, and each compaction motor 27 is provided with a lifting rod 28 at the bottom, and a shaping column 4 is provided at the bottom of the lifting rod 28, and a pressing plate 5 is detachably provided at the bottom of the shaping column 4, and a T-block 51 is provided on the top of the pressing plate 5, and each shaping column 4 is provided with a T-slot 41 at the bottom, and the T-block 51 is clamped with the T-slot 41 located in a straight line; A push rod motor 6 is provided on the top of two adjacent columns 21, and the output shaft of the push rod motor 6 is detachably connected to the lifting motor 24. A T-shaped first groove 61 is provided on one side of the end of the output shaft of the push rod motor 6, and a U-shaped block 62 is provided inside the first groove 61. A spring 63 is provided at the bottom of the U-shaped block 62, and the spring 63 is connected to the bottom of the first groove 61. A second groove 241 is provided on each side of the housing of the lifting motor 24 corresponding to the two push rod motors 6. The output shaft of the push rod motor 6 extends into the second groove 241 and is slidably connected to the second groove 241. After the end of the U-shaped block 62 pops up, it is clamped with the limiting groove 242 provided on the top of the second groove 241; Five seepage holes 31 are provided at equal intervals on the simulated wellbore 3; The lifting motor 24, the push rod motor 6 and each compacting motor 27 are all equipped with a built-in PLC controller, and the PLC controller is connected to an external control system.

[0019] Example 2 The difference between this embodiment and embodiment 1 is that: Seven compacting motors 27 are arranged at equal intervals at the bottom of the connecting rod 26 .

[0020] Example 3 The difference between this embodiment and embodiment 1 is that: Eight compacting motors 27 are arranged at equal intervals at the bottom of the connecting rod 26 .

[0021] Example 4 A method for simulating oil recovery by injecting carbon dioxide into a water-driven oil reservoir, according to a device for simulating oil recovery by injecting carbon dioxide into a water-driven oil reservoir in Example 1, comprises the following steps: S1. Small layer structure simulation: S1-1: X-axis direction simulation: Add simulated stratum sand body into the square box 1, and then shape the simulated stratum sand body through the compaction component 2, move the lifting motor 24 of the compaction component 2 to the side of the cross slide 22 through the push rod motor 6, keep each shaping column 4 at the same horizontal line and install a pressing plate 5 at the bottom of each shaping column 4, turn on the lifting motor 24 to lower the shaping column 4, use the pressing plate 5 to compact the edge of the simulated stratum sand body, then raise the shaping column 4, remove the pressing plate 5, and lower the shaping column 4 again to the surface of the simulated stratum sand body. Turn on the push rod motor 6 to push the lifting motor 24 to slide along the slide groove 23 and drive the shaping column 4 to slide along the surface of the simulated formation sand body. At the same time, according to the elevation map of the small layer set in advance, turn on each compaction motor 27 while moving the shaping column 4, drive the shaping column 4 to slide up and down while moving to highly shape the simulated formation sand body, until the shaping column 4 moves to the edge of the square box 1, and then compact the simulated formation sand body on this side, reverse the direction and highly shape it again, repeat several times, and complete the simulation of the X-axis trend of the simulated formation sand body of the small layer; S1-2, Y-axis trend simulation: reset the compaction assembly 2, move the lifting motor 24 to the middle of the cross slide 22 through the push rod motor 6, release the connection between the push rod motor 6 and the lifting motor 24, then dock the output shaft of another push rod motor 6 with the lifting motor 24, turn on the electric shaft 25 to drive the connecting rod 26 to rotate 90°, then move the lifting motor 24 to one side of the cross slide 22 through the push rod motor 6, and then use the same compaction and height shaping method as in step S1-1 to complete the Y-axis trend simulation of the small layer simulated formation sand body; The number of repetitions in step S1-1 is 2 to 3 times, the number of repetitions in step S1-2 is 2 to 3 times, the particle size of the simulated formation sand body is 0.05 to 0.1 μm, and the particle size of the simulated surface sand body is 0.5 to 1 μm; S2, oil layer structure simulation: after completing the trend simulation of several small layers of simulated formation sand bodies according to the method in step S1, the oil layer structure simulation is performed. After completing the trend simulation of the simulated formation sand body for the small layer as the oil layer, simulated formation oil is poured on the surface of the simulated formation sand body. After standing for 15-20 minutes, the trend simulation of the next small layer of simulated formation sand body can be performed; S3, stratigraphic structure simulation: after completing the trend simulation of the simulated stratigraphic sand bodies of all sub-layers and oil layers according to the methods in steps S1 and S2, the simulated surface sand body is covered on the last sub-layer to complete the stratigraphic structure simulation; S4, well location layout: 1 to 3 simulated oil production wells are arranged at any position in the formation structure, and 3 to 6 simulated water injection wells are arranged around the oil production wells, the seepage holes 31 corresponding to the oil layer positions of the simulated wellbore 3 are opened, and then the simulated wellbore 3 is inserted into the corresponding well location, and the top positions of each simulated wellbore 3 are the same; S5, pressurization and compaction: add simulated surface sand again, so that the simulated surface sand is 3-5 cm above the top of each simulated wellbore 3, mark the top position of each simulated wellbore 3, then place the pressing block 11 on the simulated surface sand, reset the compaction assembly 2, move the lifting motor 24 to the middle of the cross slide 22 through the push rod motor 6, keep each shaping column 4 at the same horizontal line and install a pressing plate 5 at the bottom of each shaping column 4, turn on the lifting motor 24 to lower the shaping column 4, use the pressing plate 5 to press down the pressing block 11 to pressurize and compact the entire simulated stratum structure, and heat the simulated stratum structure through a heater, the heating temperature is 85-90°C, the pressurization and compaction pressure is 15-20MPa, and the pressurization and compaction time is 12-24h; S6, simulated water injection: inject water into the simulated wellbore 3 at the simulated water injection well location to displace the simulated formation oil in the oil layer, and produce it from the simulated wellbore 3 at the simulated oil production well location, and record the recovery rate; S7. Simulate carbon dioxide intake and discharge: inject carbon dioxide into the simulated wellbore 3 at the simulated water injection well location for 10-12 hours, stop injection for 5-6 hours, repeat 3-5 times, displace the simulated formation oil in the oil layer, and produce it from the simulated wellbore 3 at the simulated oil production well location, and record the recovery rate.

[0022] Experimental example A simulation experiment was carried out according to the apparatus and method in Example 1 and Example 4. Taking the actual working conditions of an oil field in western my country as an example, a real proportionally scaled formation height fluctuation was introduced, and water injection and carbon dioxide injection were simulated successively. When S6, simulated water injection, was performed, it was measured that the recovery rate was 24% when the simulated crude oil water content was greater than 90%. The recovery rate of an oil reservoir refers to the ratio of the amount of crude oil produced to the original geological reserves of the oil reservoir, which is the ratio of the amount of simulated formation oil produced to the total simulated formation oil. When S7, simulated carbon dioxide throughput, was performed, the recovery rate reached 33%, which can reflect the effect of carbon dioxide throughput on the recovery of water-driven oil reservoirs.

Claims

1. A water-flooded oil reservoir carbon dioxide injection simulation device, characterized in that: It comprises a square box (1) for carrying a simulated formation sand body, a compaction assembly (2) located above the square box (1) for compacting and shaping the simulated formation sand body, and a simulated wellbore (3) embedded in the simulated formation sand body; The compaction assembly (2) comprises a column (21) located in the middle of the four sides of the square box (1), each column (21) is fixedly connected to a cross slide (22) at the top, a slide groove (23) is provided in the middle of the cross slide (22), a lifting motor (24) sliding along the slide groove (23) is provided on the top of the cross slide (22), the output end of the lifting motor (24) passes through the slide groove (23) and an electric shaft (25) is provided at the rear end, a connecting rod (26) is provided at the bottom output end of the electric shaft (25), a plurality of compaction motors (27) are arranged at equal intervals at the bottom of the connecting rod (26), each compaction motor (27) is provided with a lifting rod (28) at the bottom, a shaping column (4) is provided at the bottom of the lifting rod (28), and a detachable pressing plate (5) is provided at the bottom of the shaping column (4); The simulated wellbore (3) is provided with a plurality of seepage holes (31) at equal intervals.

2. A water-flooding reservoir carbon dioxide injection oil recovery simulation device according to claim 1, characterized in that: A push rod motor (6) is provided on the top of two adjacent uprights (21), and an output shaft of the push rod motor (6) is detachably connected to the lifting motor (24).

3. A water-flooding reservoir carbon dioxide injection oil recovery simulation device according to claim 2, characterized in that: A T-shaped first groove (61) is provided at one end of the output shaft of the push rod motor (6), a U-shaped block (62) is provided inside the first groove (61), a spring (63) is provided at the bottom of the U-shaped block (62), and the spring (63) is connected to the bottom of the first groove (61). A second groove (241) is provided on each side of the housing of the lifting motor (24) corresponding to the two push rod motors (6), the output shaft of the push rod motor (6) extends into the second groove (241) and is slidably connected to the second groove (241), and the end of the U-shaped block (62) is snapped up and engaged with a limit groove (242) provided at the top of the second groove (241).

4. A water-flooding reservoir carbon dioxide injection oil recovery simulation device according to claim 1, characterized in that: The number of shaping columns (4) is 6 to 8.

5. A water-flooding reservoir carbon dioxide injection oil flooding simulation device according to claim 1, characterized in that: The lifting motor (24), the push rod motor (6) and each of the compacting motors (27) are all equipped with a built-in PLC controller, and the PLC controller is connected to an external control system.

6. A water-flooding reservoir carbon dioxide injection oil flooding simulation device according to claim 1, characterized in that: A T-shaped block (51) is provided on the top of the pressing plate (5), and a T-shaped slot (41) is provided on the bottom of each shaping column (4), and the T-shaped block (51) is clamped with the T-shaped slot (41) located on a straight line.

7. A water-flooding reservoir carbon dioxide injection oil flooding simulation device according to claim 1, characterized in that: The square box (1) is also provided with a detachable pressing block (11) which is slidably fitted with the inner wall thereof and is used for compacting the simulated formation sand body. A heater (12) is provided on each side of the square box (1).

8. A method for simulating oil recovery by injecting carbon dioxide into a water-driven oil reservoir, according to a device for simulating oil recovery by injecting carbon dioxide into a water-driven oil reservoir according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. Small layer structure simulation: S1-1: X-axis direction simulation: Add simulated stratum sand body into the square box (1), then shape the simulated stratum sand body through the compaction component (2), move the lifting motor (24) of the compaction component (2) to the side of the cross slide (22) through the push rod motor (6), keep each shaping column (4) at the same horizontal line and install a pressure plate (5) under each shaping column (4), turn on the lifting motor (24) to lower the shaping column (4), use the pressure plate (5) to compact the edge of the simulated stratum sand body, then raise the shaping column (4), remove the pressure plate (5), and lower the shaping column (4) again to the simulated stratum sand body. The surface of the simulated stratum sand body is moved, the push rod motor (6) is turned on to push the lifting motor (24) to slide along the slide groove (23) and drive the shaping column (4) to slide along the surface of the simulated stratum sand body. At the same time, according to the elevation map of the small layer set in advance, each compaction motor (27) is turned on while the shaping column (4) is moved, so as to drive the shaping column (4) to slide up and down during movement to highly shape the simulated stratum sand body, until the shaping column (4) moves to the edge of the square box (1), and then the simulated stratum sand body on this side is compacted, and the direction is reversed to highly shape again, and this is repeated several times to complete the simulation of the X-axis trend of the simulated stratum sand body of the small layer; S1-2, Y-axis trend simulation: reset the compaction assembly (2), move the lifting motor (24) to the middle of the cross slide (22) through the push rod motor (6), release the connection between the push rod motor (6) and the lifting motor (24), then connect the output shaft of another push rod motor (6) to the lifting motor (24), turn on the electric shaft (25) to drive the connecting rod (26) to rotate 90 degrees, then move the lifting motor (24) to one side of the cross slide (22) through the push rod motor (6), and then use the same compaction and height shaping method as in step S1-1 to complete the Y-axis trend simulation of the small layer simulated formation sand body; S2, oil layer structure simulation: after completing the trend simulation of several small layers of simulated formation sand bodies according to the method in step S1, the oil layer structure simulation is performed. After completing the trend simulation of the simulated formation sand body for the small layer as the oil layer, simulated formation oil is poured on the surface of the simulated formation sand body. After standing for 15-20 minutes, the trend simulation of the next small layer of simulated formation sand body can be performed; S3, stratigraphic structure simulation: after completing the trend simulation of the simulated stratigraphic sand bodies of all sub-layers and oil layers according to the methods in steps S1 and S2, the simulated surface sand body is covered on the last sub-layer to complete the stratigraphic structure simulation; S4, well location layout: 1 to 3 simulated oil production well locations are arranged at any position in the formation structure, and 3 to 6 simulated water injection well locations are arranged around the oil production wells, the seepage holes (31) corresponding to the oil layer positions of the simulated wellbore (3) are opened, and then the simulated wellbore (3) is inserted into the corresponding well location, and the top positions of each simulated wellbore (3) are the same; S5, pressurization and compaction: add simulated surface sand again, so that the simulated surface sand is 3-5 cm above the top of each simulated wellbore (3), mark the top position of each simulated wellbore (3), then place the pressing block (11) on the simulated surface sand, reset the compaction assembly (2), move the lifting motor (24) to the middle of the cross slide (22) through the push rod motor (6), keep each shaping column (4) at the same horizontal line and install a pressing plate (5) under each shaping column (4), start the lifting motor (24) to lower the shaping column (4), use the pressing plate (5) to press down the pressing block (11) to pressurize and compact the entire simulated stratum structure, and heat the simulated stratum structure with a heater, the heating temperature is 85-90°C, the pressurization and compaction pressure is 15-20MPa, and the pressurization and compaction time is 12-24h; S6, simulated water injection: inject water into the simulated wellbore (3) at the simulated water injection well location to displace the simulated formation oil in the oil layer, and produce it from the simulated wellbore (3) at the simulated oil production well location, and record the recovery rate; S7. Simulate carbon dioxide injection: inject carbon dioxide into the simulated wellbore (3) at the simulated water injection well location for 10 to 12 hours, stop injecting for 5 to 6 hours, and repeat 3 to 5 times to displace the simulated formation oil in the oil layer, and then produce it from the simulated wellbore (3) at the simulated oil production well location, and record the recovery rate.

9. A method for simulating oil recovery by injecting carbon dioxide into a water-driven oil reservoir according to claim 8, characterized in that: The number of repetitions in step S1-1 is 2 to 3 times, the number of repetitions in step S1-2 is 2 to 3 times, the particle size of the simulated formation sand body is 0.05 to 0.1 μm, and the particle size of the simulated surface sand body is 0.5 to 1 μm.

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