Replaceable horizontal slot reservoir physical simulation device and method

Abstract

This invention relates to a replaceable and adaptable physical simulation device and method for horizontally fractured reservoirs, specifically in the field of oil and gas field development technology. The device and method include a replaceable horizontally fractured physical model and an injection system and a production system connected to the model. The replaceable horizontally fractured physical model comprises a solidified shell containing several simulated reservoirs arranged sequentially from top to bottom. Each simulated reservoir contains a sealed and fixed simulated core plate. This invention features a simple structure and ease of use. The simulated core plate can be replaced, and horizontally fractured simulation grooves can be etched onto it as needed. This allows for single control of the horizontally fractured size, properties, and spacing, maintaining consistent reservoir conditions and resulting in more accurate experimental results. The replacement and fabrication of the simulated core plate and the etched horizontally fractured simulation grooves are convenient and quick.

Description

Technical Field

[0001] This invention relates to the field of oil and gas field development technology, and in particular to a replaceable and adaptable physical simulation device and method for horizontal fractured reservoirs. Background Technology

[0002] Domestic and international studies have shown that the morphology of fracturing fractures in oil reservoirs at different depths has complex characteristics. It is generally believed that reservoirs at a depth of 600m are mostly horizontal fractures, while those at a depth of 600-1200m are often complex fractures (vertical fractures, torsional fractures, and horizontal fractures may coexist), and deep fractures above 1200m are vertical fractures.

[0003] Oil reservoirs with shallow burial depths and well-developed horizontal fracture systems generally exhibit the following typical development characteristics: low single-well productivity, high overall water cut; significant decline in production and low recovery rate during depletion development; and severe reservoir heterogeneity. Due to the presence of fractured horizontal fractures, oilfields are prone to rapid water flooding within a short period, even experiencing flooding immediately after injection. This results in low injected water utilization, increasingly prominent injection-production contradictions, significant management difficulties, and ineffective replenishment of formation energy, leading to unsatisfactory water injection effects. Bottom water injection, where injection wells inject 3-5 times the conventional injection volume, creates artificial bottom water with a certain energy level at the bottom of the reservoir within a short time. Based on this, gravity differentiation and capillary forces are used to displace and drive away crude oil retained within the micropores. This water injection method can effectively replenish formation energy while slowing the rapid advance of injected water along fractures, increasing the swept volume and utilization rate of injected water, reducing the water cut rise rate, and maintaining stable production for a longer period. This method has significant practical implications for the development of tight, shallow, horizontally fractured oil reservoirs.

[0004] In actual oil recovery processes, reservoir conditions are highly complex, with varying horizontal fracture sizes, spacing, and properties. The impact of different horizontal fracture conditions on reservoir recovery efficiency and time remains unclear, and currently, there are no suitable physical simulation experiments or methods, either domestically or internationally. Currently, there are few physical simulation models for bottom-injection horizontal fractures and their related recovery mechanisms, and the core samples used in these simulations are mostly natural outcrops with fractures created by hydraulic fracturing or artificial splitting. The properties of natural cores lack controllability, resulting in low inter-experimental contrast; the size and scale of hydraulically fractured fractures cannot be precisely controlled, affecting experimental results. To address these issues, this invention develops a replaceable and adaptable horizontal fracture reservoir physical simulation device and its fabrication method. By artificially fabricating replaceable core plates, the size and spacing of horizontal fractures can be controlled while maintaining constant reservoir conditions, enabling simulation analysis of the impact of horizontal fractures under different conditions on reservoir recovery, thus solving the problem of uncontrollable horizontal fracture and model size and properties. Summary of the Invention

[0005] To address the aforementioned issues, this invention provides a method for creating a replaceable horizontal fracture physical model that maintains constant reservoir conditions and controllable horizontal fracture conditions. It also clarifies the impact of different horizontal fracture sizes, properties, and spacings on recovery rate under the same reservoir conditions. This invention provides a replaceable and adaptable horizontal fracture reservoir physical simulation device and method.

[0006] The present invention provides a replaceable and adaptable horizontal fracture reservoir physical simulation device, comprising a replaceable horizontal fracture physical model and an injection system and a production system respectively connected to the replaceable horizontal fracture physical model. The replaceable horizontal fracture physical model includes a solidified shell, and a plurality of simulated reservoirs are arranged sequentially from top to bottom inside the solidified shell. Each simulated reservoir is sealed and fixedly provided with a simulated core plate.

[0007] The simulated core plate located at the top is called the top core plate, the simulated core plate located at the bottom is called the bottom core plate, and the simulated core plate located between the top core plate and the bottom core plate is called the intermediate core plate. There are several intermediate core plates.

[0008] It also includes cylindrical simulated injection wells and simulated production wells. One end of the simulated injection well passes through the top core plate and the middle core plate in sequence and extends into the bottom core plate. The other end of the simulated injection well extends out of the solidified shell and is connected to the injection system.

[0009] One end of the simulated production well extends into the solidified shell, and the other end extends out of the solidified shell and is connected to the production system.

[0010] Each simulated reservoir is equipped with several monitoring sensor groups. Each monitoring sensor group includes a pressure sensor and a resistivity sensor that are respectively installed on both sides of the core plate in the simulated reservoir. The pressure sensor and the resistivity sensor are respectively connected to a data acquisition device installed outside the solidified shell through connecting lines.

[0011] Preferably, it also includes a horizontal joint simulation groove, which is disposed on the top core plate and / or the bottom core plate and / or the middle core plate.

[0012] Preferably, the injection system includes a displacement pump, which is connected to one end of the simulated injection well extending out of the solidification shell via a piston container, and a pressure gauge and a flow metering valve are installed on the pipeline between the piston container and the simulated injection well.

[0013] Preferably, the production system includes an oil-water separator, which is provided with an inlet end, a first liquid outlet end and a second liquid outlet end. The inlet end of the oil-water separator is connected to one end of the simulated production well extending out of the solidified shell through a back pressure valve. The first liquid outlet end and the second liquid outlet end are respectively connected to fluid collectors through flow metering valves.

[0014] Preferably, the simulated core plate is made of ultrafine cement, gypsum and quartz sand in a mass ratio of 1:1:2.

[0015] Preferably, both the simulated reservoir and the horizontal fracture simulation trench are made of cemented quartz sand.

[0016] Preferably, auxiliary replacement devices are provided at both ends of the simulated core plate;

[0017] The auxiliary replacement device includes a fixing rod, one end of which is fixedly connected to the simulated core plate. Each fixing rod is fitted with a nut post for connecting the simulated core plate to the solidified shell.

[0018] A method for manufacturing a simulation device, used to create a replaceable and adaptable physical simulation device for horizontally fractured reservoirs, includes the following steps:

[0019] (1) Replaceable horizontal seam physical model creation:

[0020] A) Simulated reservoir construction: A cemented silica sand construction method is used. Ultrafine cement, silica sand, and gypsum are poured in layers into a replaceable horizontal joint physical model mold according to the required proportions to construct the simulated reservoir. A first-type steel plate, with the same length as the simulated reservoir but a smaller width, is placed inside the simulated reservoir as needed. The distance between the two sides of the first-type steel plate and the edge of the simulated reservoir is 1-3 cm, and the thickness of the first-type steel plate is 1-3 cm. Finally, the simulated reservoir is constructed, forming a replaceable horizontal joint physical model.

[0021] B) Monitoring point layout: After the replaceable horizontal seam physical model is bonded, several pressure monitoring points and resistance monitoring points are laid out alternately on one side of the replaceable horizontal seam physical model according to experimental needs.

[0022] C) After bonding the outer side of the model and placing the pressure sensor and resistivity sensor at the monitoring points, the first type of steel plate is removed and replaced with a second type of steel plate with the same thickness and width as the removed first type of steel plate, but with a length greater than that of the simulated reservoir. The outer layer of the replaceable horizontal seam physical model is then bonded with epoxy resin.

[0023] D) Make a solidified shell using acrylic sheets. Make a frame with a length, width and height greater than the replaceable horizontal seam physical model. Place the replaceable horizontal seam physical model in the frame with the sensor side facing upward. Stir high-strength concrete UHPC. Mix high-strength concrete UHPC with water at a weight ratio of 10:1. Pour the well-mixed high-strength concrete slurry into the frame and let it stand for 5-7 days until the slurry is completely solidified.

[0024] (2) Simulation of core plate fabrication:

[0025] A) Prepare ultrafine cement, gypsum and quartz sand of different mesh sizes, and an acrylic mold that matches the size of the simulated core plate.

[0026] B) Mix ultrafine cement, gypsum and quartz sand in proportion, and dry mix with a mixer for 3-5 minutes to fully mix the three to form cement mortar. The mesh size of the selected quartz sand is determined according to the permeability of the simulated core plate.

[0027] C) Add water at a weight of 10% of the total weight of the mixed cement mortar to the mixed cement mortar, and use a mixer to wet mix for 5-10 minutes to fully mix, remove air bubbles, and mix evenly.

[0028] D) Pour the mixed cement mortar into the acrylic sheet mold;

[0029] E) Place the acrylic sheet mold in a sunny, well-ventilated and dry place to dry and cure for 3-5 days until the cement mortar is completely cured, forming a semi-finished simulated rock core board.

[0030] F) Remove the solidified simulated core plate semi-finished product;

[0031] G) Drill holes in the middle of both ends of the simulated core plate semi-finished product, insert fixing rods, and use adhesive to fix the fixing rods to the simulated core plate semi-finished product.

[0032] H) The simulated core plate semi-finished product is consistent with the second type of steel plate. The length, width and thickness of the horizontal seam are etched according to the requirements to prevent breakage during replacement.

[0033] (3) Simulation of core plate fixation:

[0034] A) Drill holes in a 2mm thick HDPE membrane according to the permeability and porosity requirements of the simulated core board, and then use the drilled HDPE membrane to wrap the semi-finished simulated core board. Do not attach HDPE membrane to the two ends with fixing rods. After the HDPE membrane is attached, let it stand for 1-2 days until the adhesive is completely dry to form the simulated core board.

[0035] B) Remove the second type of steel plate from the replaceable horizontal seam physical model;

[0036] C) Slowly insert the simulated core plate into the position of the second type of steel plate that has been removed, so that the HDPE film can fully contact the physical model of the replaceable horizontal seam;

[0037] D) After the simulated core plate is inserted into the replaceable horizontal seam physical model, the simulated core plate and the solidified shell are fixedly connected at both ends of the replaceable horizontal seam physical model using nut columns. Then, resin glue is used to fix and seal the core plate and the connection between the simulated core plate and the replaceable horizontal seam physical model.

[0038] (4) Set up simulated injection wells and simulated production wells:

[0039] A) The first replacement of the replaceable horizontal fracture physical model containing the simulated core plate was carried out together with drilling. The second replacement of the simulated core plate was carried out in advance with drilling to reserve the well position.

[0040] B) Replaceable horizontal fracture physical model with separate drilling at the injection and production ends;

[0041] C) Wrap a 1mm thick HDPE membrane around the outside of the simulated wellbore using resin adhesive;

[0042] D) Insert a simulated wellbore string, with the bottom of the simulated wellbore string extending into the simulated core plate to form a simulated injection well and a simulated production well.

[0043] A method for using a simulation device, comprising connecting experimental equipment and materials according to a replaceable and adaptable horizontal fractured reservoir physical simulation device, the method including the following steps:

[0044] Set the displacement pressure, adjust the back pressure valve, and connect the displacement pump to the lower inlet of the three containers in the piston container that contain formation water, formation oil, and displacement fluid through a six-way valve.

[0045] Turn on the displacement pump switch, the inlet and outlet switches of the piston container containing formation water, close the inlet and outlet switches of the piston container containing formation crude oil and displacement fluid, and the injection and production system switches of the replaceable horizontal fracture physical model. Inject 20 times the pore volume of water into the replaceable horizontal fracture physical model to fully saturate the replaceable horizontal fracture physical model with water.

[0046] Open the inlet and outlet switches of the piston container containing formation crude oil, close the inlet and outlet switches of the piston container containing formation water and displacement fluid, open other switches, and displace until no more water is produced at the outlet, so that the replaceable horizontal fracture physical model is fully saturated with formation crude oil. Close all valves, observe and record the water production data. The amount of water displaced is the amount of saturated formation crude oil. Divide the amount of saturated formation crude oil by the pore volume of the replaceable horizontal fracture physical model to obtain the oil saturation.

[0047] Open the inlet and outlet switches of the piston container containing the displacement fluid, close the inlet and outlet switches of the piston container containing formation water and formation oil, open other switches, and displace until no more formation crude oil is produced at the outlet. Close all valves and record the experimental data of water injection, oil production, fluid production, pressure and resistivity changes at each monitoring point through the data acquisition system. Calculate the experimental results of recovery rate, water cut, pressure field map, and oil saturation field map.

[0048] This invention has a simple structure and is easy to use. The simulated core plate can be replaced, and horizontal fracture simulation grooves can be etched on the simulated core plate as needed. It can achieve single control of the scale, physical properties and spacing of the horizontal fractures, keep the reservoir conditions unchanged, and make the experimental results more accurate. The simulated core plate and the etched horizontal fracture simulation grooves are easy and quick to replace and manufacture. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of a replaceable and adaptable physical simulation device for horizontal fractured reservoirs.

[0050] Figure 2 This is a schematic diagram of the physical model of a replaceable horizontal seam.

[0051] Figure 3 A top view of a simulated core plate with auxiliary replacement devices and etched horizontal grooves.

[0052] Figure 4 Right view of the replaceable horizontal seam physical model.

[0053] Figure 5 This is a schematic diagram of pressure and resistivity monitoring points.

[0054] Figure 6 This is a schematic diagram of three simulated core plates in the embodiment.

[0055] Figure 7 This is a physical model diagram of an alternative horizontal joint without a simulated core plate installed in the embodiment.

[0056] Figure 8 This is a three-dimensional view of a simulated core plate with horizontal grooves etched in the embodiment.

[0057] Reference numerals: 1-Displacement pump, 2-Piston container; 3-Replaceable horizontal fracture physical model, 4-Data acquisition system, 5-Oil-water separator, 6-Fluid collector, 8-Pressure gauge, 9-Back pressure valve, 10-Flow metering device, 14-Top core plate, 15-Intermediate core plate, 16-Bottom core plate, 17-Horizontal fracture simulation trench, 19-Fixing rod, 22-Nut column, 25-Simulated injection well, 26-Simulated production well, 27-Pressure monitoring point, 28-Resistivity monitoring point, 32-Simulated reservoir. Detailed Implementation

[0058] The present invention provides a replaceable and adaptable horizontal fracture reservoir physical simulation device, comprising a replaceable horizontal fracture physical model 3 and an injection system and a production system respectively connected to the replaceable horizontal fracture physical model 3. The replaceable horizontal fracture physical model 3 includes a solidified shell, and a plurality of simulated reservoirs 32 are arranged sequentially from top to bottom inside the solidified shell. Each simulated reservoir 32 is sealed and fixedly provided with a simulated core plate.

[0059] The simulated core plate located at the top is the top core plate 14, the simulated core plate located at the bottom is the bottom core plate 16, and the simulated core plate located between the top core plate 14 and the bottom core plate 16 is the intermediate core plate 15. Several intermediate core plates 15 are provided.

[0060] It also includes a cylindrical simulated injection well 25 and a simulated production well 26. One end of the simulated injection well 25 passes through the top core plate 14 and the middle core plate 15 in sequence and extends into the bottom core plate 16. The other end of the simulated injection well 25 extends out of the solidified shell and is connected to the injection system.

[0061] One end of the simulated production well 26 extends into the solidified shell, and the other end extends out of the solidified shell and is connected to the production system.

[0062] Each simulated reservoir 32 is equipped with several monitoring sensor groups. Each monitoring sensor group includes a pressure sensor and a resistivity sensor that are respectively installed on both sides of the core plate in the simulated reservoir 32. The pressure sensor and the resistivity sensor are respectively connected to a data acquisition device installed outside the solidified shell through connecting lines.

[0063] It also includes a horizontal joint simulation groove 17, which is disposed on the top core plate 14 and / or the bottom core plate 16 and / or the middle core plate 15.

[0064] The injection system includes a displacement pump 1, which is connected to one end of the simulated injection well 25 extending out of the solidification shell via a piston container 2. A pressure gauge 8 and a flow metering valve are installed on the pipeline between the piston container 2 and the simulated injection well 25.

[0065] The production system includes an oil-water separator 5, which is equipped with an inlet end, a first liquid outlet end and a second liquid outlet end. The inlet end of the oil-water separator 5 is connected to one end of the simulated production well 26 that extends out of the solidified shell through a back pressure valve 9. The first liquid outlet end and the second liquid outlet end are respectively connected to a fluid collector 6 through a flow metering valve.

[0066] The simulated core plate is made of ultrafine cement, gypsum and quartz sand in a mass ratio of 1:1:2.

[0067] Both the simulated reservoir 32 and the horizontal fracture simulation trench 17 were made of cemented quartz sand.

[0068] Auxiliary replacement devices are installed at both ends of the simulated core plate;

[0069] The auxiliary replacement device includes a fixing rod 19, one end of which is fixedly connected to the simulated core plate. Each fixing rod 19 is fitted with a nut post 22 for connecting the simulated core plate to the solidified shell.

[0070] A method for manufacturing a simulation device, used to create a replaceable and adaptable physical simulation device for horizontally fractured reservoirs, includes the following steps:

[0071] (1) Replaceable horizontal seam physical model 3 fabrication:

[0072] A) The simulated reservoir 32 is constructed using a cemented quartz sand method. Ultrafine cement, quartz sand, and gypsum are poured in layers into the replaceable horizontal joint physical model 3 mold according to the required proportions to construct the simulated reservoir 32. A first-type steel plate, with the same length as the simulated reservoir 32 but a smaller width, is placed inside the simulated reservoir 32 as needed for the experiment. The distance between the two sides of the first-type steel plate and the edge of the simulated reservoir 32 is 1-3 cm, and the thickness of the first-type steel plate is 1-3 cm. Finally, the simulated reservoir 32 is formed, creating the replaceable horizontal joint physical model 3.

[0073] B) Monitoring point layout: After the replacement horizontal seam physical model 3 is bonded, several pressure monitoring points 27 and resistivity monitoring points 28 are arranged on one side of the replacement horizontal seam physical model 3 according to experimental needs.

[0074] C) After bonding the outer side of the model and placing the pressure sensor and resistivity sensor at the monitoring points, the first type of steel plate is removed and replaced with a second type of steel plate with the same thickness and width as the removed first type of steel plate, but with a length greater than that of the simulated reservoir 32. The outer layer of the replaceable horizontal seam physical model 3 is then bonded with epoxy resin.

[0075] D) Make a solidified shell. Using acrylic sheets, make a frame with a length, width and height greater than the replaceable horizontal seam physical model 3. Place the replaceable horizontal seam physical model 3 in the frame with the side with the sensor facing upward. Stir high-strength concrete UHPC. Mix high-strength concrete UHPC and water at a weight ratio of 10:1. Pour the well-mixed high-strength concrete slurry into the frame and let it stand for 5-7 days until the slurry is completely solidified.

[0076] (2) Simulation of core plate fabrication:

[0077] A) Prepare ultrafine cement, gypsum and quartz sand of different mesh sizes, and an acrylic mold that matches the size of the simulated core plate.

[0078] B) Mix ultrafine cement, gypsum and quartz sand in proportion, and dry mix with a mixer for 3-5 minutes to fully mix the three to form cement mortar. The mesh size of the selected quartz sand is determined according to the permeability of the simulated core plate.

[0079] C) Add water at a weight of 10% of the total weight of the mixed cement mortar to the mixed cement mortar, and use a mixer to wet mix for 5-10 minutes to fully mix, remove air bubbles, and mix evenly.

[0080] D) Pour the mixed cement mortar into the acrylic sheet mold;

[0081] E) Place the acrylic sheet mold in a sunny, well-ventilated and dry place to dry and cure for 3-5 days until the cement mortar is completely cured, forming a semi-finished simulated rock core board.

[0082] F) Remove the solidified simulated core plate semi-finished product;

[0083] G) Drill holes in the middle of both ends of the simulated core plate semi-finished product, insert fixing rods 19, and use adhesive to fix the fixing rods 19 to the simulated core plate semi-finished product.

[0084] H) The simulated core plate semi-finished product is consistent with the second type of steel plate. The length, width and thickness of the horizontal seam are etched according to the requirements to prevent breakage during replacement.

[0085] (3) Simulation of core plate fixation:

[0086] A) Drill holes in a 2mm thick HDPE membrane according to the permeability and porosity requirements of the simulated core board, and then use the drilled HDPE membrane to wrap the simulated core board semi-finished product. Do not attach HDPE membrane to the two ends with fixing rod 19. After the HDPE membrane is attached, let it stand for 1-2 days until the adhesive is completely dry to form the simulated core board.

[0087] B) Remove the second type of steel plate from the replaceable horizontal seam physical model 3;

[0088] C) Slowly insert the simulated core plate into the position of the second type of steel plate that has been removed, so that the HDPE film can fully contact the replaceable horizontal seam physical model 3;

[0089] D) After the simulated core plate is inserted into the replaceable horizontal seam physical model 3, the simulated core plate and the solidified shell are fixedly connected at both ends of the replaceable horizontal seam physical model 3 using nut posts 22. Then, resin glue is used to fix and seal the core plate around the nut posts 22 and at the junction of the simulated core plate and the replaceable horizontal seam physical model 3.

[0090] (4) Set up simulated injection well 25 and simulated production well 26:

[0091] A) The replacement horizontal fracture physical model 3 containing the simulated core plate, which was replaced for the first time, was drilled together. The simulated core plate was replaced for the second time and holes were drilled in advance to reserve the well position.

[0092] B) Replaceable horizontal fracture physical model 3: Drill wells at the injection and production ends separately;

[0093] C) Wrap a 1mm thick HDPE membrane around the outside of the simulated wellbore using resin adhesive;

[0094] D) Insert a simulated wellbore string, with the bottom of the simulated wellbore string extending into the simulated core plate to form a simulated injection well 25 and a simulated production well 26.

[0095] A method for using a simulation device, comprising connecting experimental equipment and materials according to a replaceable and adaptable horizontal fractured reservoir physical simulation device, the method including the following steps:

[0096] Set the displacement pressure, adjust the back pressure valve 9, and connect the displacement pump 1 to the lower inlet of the three containers in the piston container 2 containing formation water, formation oil, and displacement fluid respectively through the six-way valve.

[0097] Turn on the displacement pump 1 switch, the inlet and outlet switches of the piston container 2 containing formation water, close the inlet and outlet switches of the piston container 2 containing formation crude oil and displacement fluid, and the injection and production system switches of the replaceable horizontal fracture physical model 3. Inject 20 times the pore volume of water into the replaceable horizontal fracture physical model 3 to fully saturate the replaceable horizontal fracture physical model 3 with water.

[0098] Open the inlet and outlet switches of piston container 2 containing formation crude oil, close the inlet and outlet switches of piston container 2 containing formation water and displacement fluid, open other switches, and displace until no more water is produced at the outlet end, so that the replaceable horizontal fracture physical model 3 is fully saturated with formation crude oil. Close all valves, observe and record the water production data. The amount of water displaced is the amount of saturated formation crude oil. Divide the amount of saturated formation crude oil by the pore volume of the replaceable horizontal fracture physical model 3 to obtain the oil saturation.

[0099] Open the inlet and outlet switches of piston container 2 containing displacement fluid, close the inlet and outlet switches of piston container 2 containing formation water and formation oil, open other switches, and displace until no more formation crude oil is produced at the outlet. Close all valves and record the experimental data of water injection, oil production, fluid production, pressure and resistivity changes at each monitoring point through data acquisition system 4. Calculate the experimental results of recovery rate, water cut, pressure field map, and oil saturation field map.

[0100] Example 1

[0101] 1. Construct a replaceable horizontal joint physical model 3 according to the above method. Add mixed mud in three layers to a 30*5*30cm mold to create three simulated reservoirs 32 with a permeability of 5mD, 10mD, and 30mD, each 10cm thick. The simulated reservoir 32 has dimensions of 30*5*30cm. The 5mD simulated reservoir 32 is constructed using ultrafine cement, gypsum, and 80-120 mesh quartz sand in a 1:1:2 weight ratio; the 10mD simulated reservoir 32 is constructed using ultrafine cement, gypsum, and 40-80 mesh quartz sand in a 1:1:2 weight ratio; and the 30mD simulated reservoir 32 is constructed using ultrafine cement, gypsum, and 40-80 mesh quartz sand in a 1:1:2 weight ratio. After the replaceable horizontal seam physical model 3 has cured, take out the first type of steel plate, which is 30cm long, 3cm wide, and 2mm thick, and replace it with the second type of steel plate, which is 40cm long, 3cm wide, and 2mm thick. Add 1cm of sealing resin glue to the outside of the replaceable horizontal seam physical model 3. Then, put the model into the middle of the 40*15*40 mold and pour UHPC mud into the mold to make the reinforced shell.

[0102] 2. Simulated core board production: (1) Use ultrafine cement: gypsum: 80-120 mesh quartz sand in a weight ratio of 1:1:2 to produce a top core board 14 with a permeability of 5mD; use ultrafine cement: gypsum: 40-80 mesh quartz sand in a weight ratio of 1:1:2 to produce an intermediate core board 15 with a permeability of 10mD; use ultrafine cement: gypsum: 20-40 mesh quartz sand in a weight ratio of 1:1:2 to produce a bottom core board 16 with a permeability of 30mD. The core board size is 40*3*1cm. Four simulated core boards of each permeability are produced.

[0103] The completed simulated core plate is etched with horizontal fracture simulation grooves 17. On the top core plate 14 with a permeability of 5mD, the horizontal fracture is etched on the upper right surface, 6cm from the right edge, with a length of 14cm (0.5 times the horizontal well spacing), a width of 2cm, and an etching depth of 1mm. The middle layer simulated core plate with a permeability of 10mD does not need to have horizontal fracture simulation grooves 17 etched. On the bottom core plate 16 with a permeability of 30mD, the horizontal fracture is etched on the upper left surface, 6cm from the left edge, with a length of 14cm (0.5 times the horizontal well spacing), a width of 2cm, and an etching depth of 1mm. The first-time adapted core plate does not require drilling holes.

[0104] (2) On the completed replaceable horizontal joint physical model 3, remove the upper second type of steel plate, insert the simulated core plate with a permeability of 5mD from the left side, pass the nut column 22 through the matching horizontal joint core plate fixing rod 19 and fix it on the replaceable horizontal joint physical model 3, and fix the screws on the nut column 22, as shown in the attached figure. Figure 4 As shown.

[0105] (3) Repeat step (2) to replace the second type of steel plate in the corresponding simulated reservoir 32 with simulated core plates with permeability of 10mD and 30mD in turn. In order to prevent damage to the replaceable horizontal fracture physical model 3, the replacement of simulated core plates needs to be completed in turn.

[0106] (4) Apply resin glue evenly to the junction of the three simulated core plates and the replaceable horizontal joint physical model 3, in order to seal the overall replaceable horizontal joint physical model 3 and reinforce the horizontal joint simulation groove 17.

[0107] (5) After the resin has solidified, drilling is carried out. The injection well is located 6.15 cm from the left edge of the model and the drilling depth is 30 cm. The production well is located 6.15 cm from the right edge of the model and the drilling depth is 10 cm. The longitudinal injection-production well distance is 20 cm and the horizontal well distance is 28 cm.

[0108] (6) Insert simulated injection well 25 and simulated production well 26 with a simulated well diameter of 3mm to form simulated injection well 25 and simulated production well 26, and perform solid sealing treatment.

[0109] 3. Physical simulation experiment: (1) Connect the experimental equipment and materials, as shown in the attached document. Figure 1 As shown, displacement pump 1 is connected to piston container 2, piston container 2 is connected to pressure gauge 8 and flow metering valve, and then to simulated injection well 25. Simulated production well 26 is connected to back pressure valve 9 and flow metering device 10. Production end oil-water separator 5 is connected to flow metering valve and fluid collector 6 respectively.

[0110] (2) Set the displacement pressure to 4MPa and adjust the back pressure valve 9. The displacement pressure should not exceed 10MPa, which would exceed the range that the solidified shell can withstand. The pressure of the back pressure valve 9 should be 0~0.5MPa lower than the displacement pressure. Connect the displacement pump 1 to the lower inlet of the three containers in the piston container 2 containing formation water, formation oil and displacement fluid respectively through a six-way valve.

[0111] (3) Open the displacement pump 1 switch, the inlet and outlet switches of the piston container 2 containing formation water, close the inlet and outlet switches of the piston container 2 containing formation crude oil and displacement fluid, and the injection and production system switches of the replaceable horizontal fracture physical model 3, and inject 20 times the pore volume of the replaceable horizontal fracture physical model 3 to fully saturate the replaceable horizontal fracture physical model 3 with water.

[0112] (4) Open the inlet and outlet switches of the piston container 2 containing formation crude oil, close the inlet and outlet switches of the piston container 2 containing formation water and displacement fluid, open other switches, and displace until no more water is produced at the outlet end, so that the replaceable horizontal fracture physical model 3 is fully saturated with formation crude oil. Close all valves, observe and record the water production data. The amount of water displaced is the amount of saturated formation crude oil. Divide the amount of saturated formation crude oil by the pore volume of the replaceable horizontal fracture physical model 3 to obtain the oil saturation.

[0113] (5) Open the inlet and outlet switches of the piston container 2 containing the displacement fluid, close the inlet and outlet switches of the piston container 2 containing formation water and formation oil, open other switches, displace until no more formation crude oil is produced at the outlet, close all valves, and record the experimental data of water injection, oil production, liquid production, pressure and resistivity changes at each monitoring point through the data acquisition system 4, and calculate the experimental results of recovery rate, water cut, pressure field map and oil saturation field map.

[0114] Example 2 (Controllable Horizontal Seam Size)

[0115] 1. Thoroughly clean the alternative horizontal seam physical model 3 of Example 1 with an organic solvent cleaning agent that has a strong ability to dissolve crude oil, such as benzene or toluene.

[0116] 2. Fabrication of horizontal seam simulation groove 17: (1) Using the 5mD and 30mD simulated core plates fabricated in Example 1, the simulated core plates are etched. The horizontal seam simulation groove 17 of the 5mD simulated core plate is etched on the upper right surface, 6cm from the right edge, with a length of 7cm (0.25 times the horizontal well distance), a width of 2cm, and an etching depth of 1mm. The horizontal seam simulation groove 17 of the 30mD simulated core plate is etched on the upper left surface, 6cm from the left edge, with a length of 7cm (0.25 times the horizontal well distance), a width of 2cm, and an etching depth of 1mm. The core plate needs to be drilled with well holes. The 5mD simulated core plate is drilled with injection well channels. The center of the well is 6.15cm from the left edge of the model, and the outer diameter of the well hole is 3mm.

[0117] (2) Prepare the replaceable horizontal fracture physical model 3 of Example 1. First, take out the simulated injection well 25 and the simulated production well 26. Then, take out the upper simulated core plate in Example 1. Insert the 5mD permeability core plate of Example 2 from the left side. Pass the nut column 22 through the fixing rod 19 on the simulated core plate and fix it on the replaceable horizontal fracture physical model 3. Fix the screw on the nut column 22.

[0118] (3) Replace the 30mD simulated core plate.

[0119] (4) Reinforce and seal the simulated core plate.

[0120] (5) Insert simulated injection well 25 and simulated production well 26 for solidification treatment.

[0121] 3. The physical simulation experiment method and steps are the same as in Example 1. Record experimental data such as water injection volume, oil production volume, liquid production volume, pressure and resistivity changes at each monitoring point, and calculate experimental results such as recovery rate, water cut, pressure field map, and oil saturation field map.

[0122] Example 3 (Horizontal seam material properties are controllable)

[0123] 1. Thoroughly clean the alternative horizontal seam physical model 3 of Example 2 using an organic solvent cleaning agent with strong crude oil dissolving ability, such as benzene or toluene;

[0124] 2. Adapting to horizontal seam fabrication: (1) Using the simulated core plates fabricated in Example 1, etch horizontal seam simulation grooves 17. The horizontal seam simulation grooves 17 of the 5mD simulated core plate are etched on the upper right surface, 6cm from the right edge, with a length of 14cm (0.5 times the horizontal well distance), a width of 2cm, and an etching depth of 1mm. The 10mD simulated core plate does not need to etch horizontal seam simulation grooves 17. The horizontal seam simulation grooves 17 of the 30mD simulated core plate are etched on the upper left surface, 6cm from the left edge, with a length of 14cm (0.5 times the horizontal well distance), a width of 2cm, and an etching depth of 1mm. The simulated core plate needs to be drilled with well holes. The 5mD and 10mD simulated core plates are drilled with injection well channels. The center of the well is 6.15cm from the left edge of the model, and the outer diameter of the well hole is 3mm.

[0125] (2) Use ultrafine cement: gypsum: 40-80 mesh quartz sand 1:1:4, mix thoroughly to form a mixed slurry, pour the mixed slurry into the horizontal joint simulation groove 17 of the 5mD and 30mD simulated core plate after etching in step 2 and fill it. After solidification, it forms a simulated core plate with a permeability of 5mD and 30mD, and a horizontal joint simulation groove 17 with a permeability of 300mD.

[0126] (3) Prepare the replaceable horizontal fracture physical model 3 of Example 2. First, take out the simulated injection well 25 and the simulated production well 26. Then, take out the upper simulated core plate in Example 2. Insert the 5mD permeability simulated core plate of Example 3 from the left side. Pass the nut column 22 through the fixing rod 19 on the simulated core plate and fix it on the replaceable horizontal fracture physical model 3. Fix the screw on the nut column 22.

[0127] (4) Replace the 10mD and 30mD simulated core plates;

[0128] (5) Reinforce and seal the simulated core plate;

[0129] (6) Insert simulated injection well 25 and simulated production well 26 for solidification treatment.

[0130] 3. The physical simulation experiment method and steps are the same as in Example 1. Record experimental data such as water injection volume, oil production volume, liquid production volume, pressure and resistivity changes at each monitoring point, and calculate experimental results such as recovery rate, water cut, pressure field map, and oil saturation field map.

[0131] Example 4 (Controllable Horizontal Joint Spacing)

[0132] 1. Thoroughly clean the alternative horizontal seam physical model 3 of Example 3 with an organic solvent cleaning agent that has a strong ability to dissolve crude oil, such as benzene or toluene.

[0133] 2. Adapting to horizontal seam fabrication: (1) Using the three types of simulated core plates fabricated in Example 1, the simulated core plates are etched. The 5mD simulated core plate does not need to be etched. The horizontal seam simulation groove 17 of the 10mD simulated core plate is etched on the upper right surface, 6cm from the right edge, with a length of 14cm, which is 0.5 times the horizontal well distance, a width of 2cm, and an etching depth of 1mm. The horizontal seam simulation groove 17 of the 30mD simulated core plate is etched on the upper left surface, 6cm from the left edge, with a length of 14cm, which is 0.5 times the horizontal well distance, a width of 2cm, and an etching depth of 1mm. The simulated core plate needs to be drilled with well holes. The 5mD, 10mD and 30mD simulated core plates are drilled with injection well channels. The center of the well is 6.15cm from the left edge of the model, and the outer diameter of the well hole is 3mm.

[0134] (2) Prepare the replaceable horizontal fracture physical model 3 of Example 3. First, take out the simulated injection well 25 and the simulated production well 26. Then, take out the upper simulated core plate in Example 3. Insert the 5mD permeability simulated core plate of Example 4 from the left side. Pass the nut column 22 through the fixing rod 19 on the simulated core plate and fix it on the replaceable horizontal fracture physical model 3. Fix the screw on the nut column 22.

[0135] (3) Replace the 10mD and 30mD simulated core plates;

[0136] (4) Reinforce and seal the simulated core plate;

[0137] (5) After the resin has solidified, drilling is carried out. No drilling is required for injection wells. Drilling location of production wells: 6.15cm from the right edge of the model center, 20cm for drilling depth; 10cm for longitudinal injection wells and 28cm for horizontal wells.

[0138] (5) Insert simulated injection well 25 and simulated production well 26 for solidification treatment.

[0139] 3. The physical simulation experiment method and steps are the same as in Example 1. Record experimental data such as water injection volume, oil production volume, liquid production volume, pressure and resistivity changes at each monitoring point, and calculate experimental results such as recovery rate, water cut, pressure field map, and oil saturation field map.

Claims

1. A replaceable and adaptable horizontal fracture reservoir physical simulation device, comprising a replaceable horizontal fracture physical model and an injection system and a production system respectively connected to the replaceable horizontal fracture physical model, characterized in that, The replaceable horizontal fracture physical model includes a solidified shell, inside which several simulated reservoirs are arranged sequentially from top to bottom, and each simulated reservoir is sealed and fixedly equipped with a simulated core plate; The simulated core plate located at the top is called the top core plate, the simulated core plate located at the bottom is called the bottom core plate, and the simulated core plate located between the top core plate and the bottom core plate is called the intermediate core plate. There are several intermediate core plates. It also includes cylindrical simulated injection wells and simulated production wells. One end of the simulated injection well passes through the top core plate and the middle core plate in sequence and extends into the bottom core plate. The other end of the simulated injection well extends out of the solidified shell and is connected to the injection system. One end of the simulated production well extends into the solidified shell, and the other end extends out of the solidified shell and is connected to the production system. Each simulated reservoir is equipped with several monitoring sensor groups. Each monitoring sensor group includes a pressure sensor and a resistivity sensor that are respectively installed on both sides of the core plate in the simulated reservoir. The pressure sensor and the resistivity sensor are respectively connected to a data acquisition unit installed outside the solidified shell through connecting lines. It also includes a horizontal joint simulation groove, which is set on the top core plate and / or the bottom core plate and / or the middle core plate; The simulated core plate is equipped with auxiliary replacement devices at both ends.

2. The replaceable and adaptable horizontal fractured reservoir physical simulation device as described in claim 1, characterized in that, The injection system includes a displacement pump, which is connected to one end of the simulated injection well extending out of the solidified shell via a piston container. A pressure gauge and a flow metering valve are installed on the pipeline between the piston container and the simulated injection well.

3. The replaceable and adaptable horizontal fractured reservoir physical simulation device as described in claim 2, characterized in that, The production system includes an oil-water separator, which is equipped with an inlet end, a first liquid outlet end and a second liquid outlet end. The inlet end of the oil-water separator is connected to one end of the simulated production well that extends out of the solidified shell through a back pressure valve. The first liquid outlet end and the second liquid outlet end are respectively connected to fluid collectors through flow metering valves.

4. The replaceable and adaptable horizontal fractured reservoir physical simulation device as described in claim 3, characterized in that, The simulated core plate is made of ultrafine cement, gypsum and quartz sand in a mass ratio of 1:1:

2.

5. The replaceable and adaptable horizontal fractured reservoir physical simulation device as described in claim 4, characterized in that, Both the simulated reservoir and the horizontal fractured simulated trench are made of cemented quartz sand.

6. The replaceable and adaptable physical simulation device for horizontal fractured reservoirs as described in claim 1, characterized in that, The auxiliary replacement device includes a fixing rod, one end of which is fixedly connected to the simulated core plate. Each fixing rod is fitted with a nut post for connecting the simulated core plate to the solidified shell.

7. A method for manufacturing a simulation device, used to manufacture a replaceable and adaptable horizontal fractured reservoir physical simulation device as described in claim 6, characterized in that, Includes the following steps: (1) Replaceable horizontal seam physical model creation: A) Simulated reservoir construction: A cemented silica sand construction method is used. Ultrafine cement, silica sand, and gypsum are poured in layers into a replaceable horizontal joint physical model mold according to the required proportions to construct the simulated reservoir. A first-type steel plate, with the same length as the simulated reservoir but a smaller width, is placed inside the simulated reservoir as needed. The distance between the two sides of the first-type steel plate and the edge of the simulated reservoir is 1-3 cm, and the thickness of the first-type steel plate is 1-3 cm. Finally, the simulated reservoir is constructed, forming a replaceable horizontal joint physical model. B) Monitoring point layout: After the replaceable horizontal seam physical model is bonded, several pressure monitoring points and resistance monitoring points are laid out alternately on one side of the replaceable horizontal seam physical model according to experimental needs. C) After bonding the outer side of the model and placing the pressure sensor and resistivity sensor at the monitoring points, the first type of steel plate is removed and replaced with a second type of steel plate with the same thickness and width as the removed first type of steel plate, but with a length greater than that of the simulated reservoir. The outer layer of the replaceable horizontal seam physical model is then bonded with epoxy resin. D) Make a solidified shell using acrylic sheets. Make a frame with a length, width and height greater than the replaceable horizontal seam physical model. Place the replaceable horizontal seam physical model in the frame with the sensor side facing upward. Stir high-strength concrete UHPC. Mix high-strength concrete UHPC with water at a weight ratio of 10:

1. Pour the well-mixed high-strength concrete slurry into the frame and let it stand for 5-7 days until the slurry is completely solidified. (2) Simulation of core plate fabrication: A) Prepare ultrafine cement, gypsum and quartz sand of different mesh sizes, and an acrylic mold that matches the size of the simulated core plate. B) Mix ultrafine cement, gypsum and quartz sand in proportion, and dry mix with a mixer for 3-5 minutes to fully mix the three to form cement mortar. The mesh size of the selected quartz sand is determined according to the permeability of the simulated core plate. C) Add water at a weight of 10% of the total weight of the mixed cement mortar to the mixed cement mortar, and use a mixer to wet mix for 5-10 minutes to fully mix, remove air bubbles, and mix evenly. D) Pour the mixed cement mortar into the acrylic sheet mold; E) Place the acrylic sheet mold in a sunny, well-ventilated and dry place to dry and cure for 3-5 days until the cement mortar is completely cured, forming a semi-finished simulated rock core board. F) Remove the solidified simulated core plate semi-finished product; G) Drill holes in the middle of both ends of the simulated core plate semi-finished product, insert fixing rods, and use adhesive to fix the fixing rods to the simulated core plate semi-finished product. H) The simulated core plate semi-finished product is consistent with the second type of steel plate. The length, width and thickness of the horizontal seam are etched according to the requirements to prevent breakage during replacement. (3) Simulation of core plate fixation: A) Drill holes in a 2mm thick HDPE membrane according to the permeability and porosity requirements of the simulated core board, and then use the drilled HDPE membrane to wrap the semi-finished simulated core board. Do not attach HDPE membrane to the two ends with fixing rods. After the HDPE membrane is attached, let it stand for 1-2 days until the adhesive is completely dry to form the simulated core board. B) Remove the second type of steel plate from the replaceable horizontal seam physical model; C) Slowly insert the simulated core plate into the position of the second type of steel plate that has been removed, so that the HDPE film can fully contact the physical model of the replaceable horizontal seam; D) After the simulated core plate is inserted into the replaceable horizontal seam physical model, the simulated core plate and the solidified shell are fixedly connected at both ends of the replaceable horizontal seam physical model using nut columns. Then, resin glue is used to fix and seal the core plate and the connection between the simulated core plate and the replaceable horizontal seam physical model. (4) Set up simulated injection wells and simulated production wells: A) The first replacement of the replaceable horizontal fracture physical model containing the simulated core plate was carried out together with drilling. The second replacement of the simulated core plate was carried out in advance with drilling to reserve the well position. B) The injection and production ends of the alternative horizontal fracture physical model can be drilled separately; C) Wrap a 1mm thick HDPE membrane around the outside of the simulated wellbore using resin adhesive; D) Insert a simulated wellbore string, with the bottom of the simulated wellbore string extending into the simulated core plate to form a simulated injection well and a simulated production well.

8. A method of using a simulation device, characterized in that, The method of connecting experimental equipment and materials according to the replaceable and adaptable horizontal fractured reservoir physical simulation device as described in claim 3 includes the following steps: Set the displacement pressure, adjust the back pressure valve, and connect the displacement pump to the lower inlet of the three containers in the piston container that contain formation water, formation oil, and displacement fluid through a six-way valve. Turn on the displacement pump switch, the inlet and outlet switches of the piston container containing formation water, close the inlet and outlet switches of the piston container containing formation crude oil and displacement fluid, and the injection and production system switches of the replaceable horizontal fracture physical model. Inject 20 times the pore volume of water into the replaceable horizontal fracture physical model to fully saturate the replaceable horizontal fracture physical model with water. Open the inlet and outlet switches of the piston container containing formation crude oil, close the inlet and outlet switches of the piston container containing formation water and displacement fluid, open other switches, and displace until no more water is produced at the outlet end, so that the replaceable horizontal fracture physical model is fully saturated with formation crude oil. Close all valves, observe and record the water production data. The amount of water displaced is the amount of saturated formation crude oil. Divide the amount of saturated formation crude oil by the pore volume of the replaceable horizontal fracture physical model to obtain the oil saturation. Open the inlet and outlet switches of the piston container containing the displacement fluid, close the inlet and outlet switches of the piston container containing formation water and formation oil, open other switches, and displace until no more formation crude oil is produced at the outlet. Close all valves and record the experimental data of water injection, oil production, fluid production, pressure and resistivity changes at each monitoring point through the data acquisition system. Calculate the experimental results of recovery rate, water cut, pressure field map, and oil saturation field map.

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