Injection-production simulation test system for water-sealed cave underground storage simulation test

Abstract

The application provides an injection and production oil simulation test system for water-sealed rock cave underground storage simulation test, which comprises a tunnel excavation unit, a water injection unit, a grouting unit and an injection and production oil unit; the tunnel excavation unit comprises an oil storage cave excavation device and a water curtain tunnel excavation device; the water injection unit comprises a water curtain tunnel simulation water injection device and a natural underground water level simulation water adding device; the water curtain tunnel simulation water injection device and the natural underground water level simulation water adding device inject water at the same time; the grouting unit is used for grouting reinforcement of the broken zone of the oil storage cave; and the injection and production oil unit is used for sucking or discharging the oil storage in the oil storage cave. One technical effect of the application is that the design is reasonable, the underground storage injection and production oil operation state such as the storage cave excavation, the natural underground water level simulation, the surrounding rock fracture grouting, the injection and production oil storage water sealing and the like can be physically simulated according to the actual working conditions, and a systematic underground storage injection and production oil simulation test system is formed.

Description

Technical Field

[0001] This invention belongs to the field of water-sealed oil storage technology, specifically relating to an oil injection and production simulation test system for simulating water-sealed underground storage tanks. Background Technology

[0002] With its numerous advantages, such as strong regional adaptability, low operating and management costs, low investment, high safety performance, low loss, fast loading and unloading speed, and low pollution, underground water-sealed oil storage has become the best choice for oil reserves and a key development direction.

[0003] Simulation experiments are an important method for studying the water-driven oil recovery behavior in underground reservoir caverns and fractures. Their purpose is to conduct true triaxial, multi-field coupled real-world experimental simulations.

[0004] The current simulation experiments have the following problems:

[0005] Chinese Patent Application No. 201711283165.4 provides an experimental device and method for simulating the oil storage principle of an underground water-sealed oil depot. This device constructs an underground surrounding rock environment model using a water tank and a transparent rock material surrounding the tank. Inside the model, water curtain tunnels, inclined water curtain holes, oil storage chambers, and interconnected oil injection and extraction pipes, water collection tanks, and oil and water pumps are arranged sequentially from top to bottom, thus replicating the entire underground water-sealed oil depot on a scale and simulating the water-sealed oil storage process. However, this device has a small simulation scale, a limited number of oil storage chambers, a simple water curtain design, and lacks a natural groundwater level simulation device. It cannot effectively simulate the uniform seepage process of groundwater and is difficult to change the seepage state of the surrounding rock.

[0006] Chinese patent application number 202021507478.0 discloses an underground reservoir simulation testing device. This device includes surrounding rock, an underground cavern with a cavity structure, a reaction wall, a stress loading device, an oil injection and production device connected to the underground cavern, a water injection device, and a data acquisition device. It can simulate the environment of an underground reservoir under the coupled effects of stress and seepage fields. The oil injection and production device simulates the oil production process of the underground reservoir by adjusting the oil pressure and flow rate during injection. However, this device only applies the seepage field by arranging water inlets and water injection devices on the side away from the underground cavern. Its form is simple, the coupling state of the stress and seepage fields is singular, and there is no water curtain device, making it unable to effectively seal the cavern. Therefore, it cannot realistically simulate actual working conditions during the oil injection and production process.

[0007] Chinese patent application number 202020958681.3 discloses an underground storage tank operation simulation test device, which includes a storage tank, an oil inlet / outlet device, and a water inlet / outlet device. The storage tank is used to store oil, the oil inlet / outlet device injects and discharges oil through inlet / outlet pipes to simulate the oil inlet / outlet process, and the water inlet device injects water into the storage tank to simulate the infiltration process of fissure water in the storage tank. However, this device cannot change the groundwater boundary conditions, cannot simulate the geological and hydrogeological conditions of water-sealed oil depots, and is difficult to use to simulate actual working conditions such as fissure grouting and cavern excavation.

[0008] Therefore, current simulation tests suffer from technical problems such as unreasonable design, inability to accurately simulate the seepage state of the surrounding rock in caverns, and poor universality. Summary of the Invention

[0009] The present invention aims to at least solve one of the technical problems existing in the prior art, and to provide a new technical solution for an oil injection and production simulation test system for water-sealed underground reservoir simulation test.

[0010] According to one aspect of the present invention, an oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caverns is provided, comprising:

[0011] The tunnel excavation unit includes an oil storage cavern excavation device and a water curtain tunnel excavation device. The oil storage cavern excavation device is used to excavate oil storage caverns of any shape and can monitor the data parameters of the excavation process in real time. The water curtain tunnel excavation device is pre-embedded along the excavation direction of the water curtain tunnel to simulate the excavation process of the water curtain tunnel.

[0012] The water injection unit includes a water curtain tunnel simulation water injection device and a natural groundwater level simulation water filling device; the water curtain tunnel simulation water injection device and the natural groundwater level simulation water filling device inject water simultaneously to simulate the superimposed water head pressure of the surrounding rock of the underground oil storage cavern at the natural groundwater level and the artificial water curtain tunnel.

[0013] Grouting unit, the grouting unit is used to grout and reinforce the fractured zone of the oil storage cavern;

[0014] The oil injection and production unit is used to suck in or discharge oil stored in the oil storage cavern, and to control the flow rate and oil pressure of the stored oil.

[0015] Optionally, the oil storage cavern excavation device includes multiple tunnel contour frames, each with a different shape;

[0016] The oil storage cavern excavation device is placed directly in front of the oil storage cavern to be excavated.

[0017] Optionally, the water injection unit includes a high-pressure water pump, a first water tank, a first control cabinet, a first pipeline, a second pipeline, a first flow sensor, and a first pressure sensor; wherein the high-pressure water pump, the first flow sensor, and the first pressure sensor are electrically connected to the first control cabinet.

[0018] The input end of the high-pressure water pump is connected to the first water tank, the first output end is connected to the water curtain tunnel simulation water injection device through the first pipeline, and the second output end is connected to the natural groundwater level simulation water filling device through the second pipeline.

[0019] The first flow sensor and the first pressure sensor are installed on both the first pipeline and the second pipeline.

[0020] Optionally, the water curtain tunnel simulation water injection device includes two water curtain tunnels, which are located on opposite sides above the oil injection and production unit.

[0021] Multiple rows of pre-embedded thin pipes are arranged along the longitudinal direction of the water curtain tunnel. The pre-embedded thin pipes are equipped with drill holes, which form a water curtain surrounding the oil storage cavern.

[0022] Each of the water curtain tunnels is connected to a connecting pipe, and the two connecting pipes are connected to the first pipeline through a T-joint.

[0023] The tee joint is equipped with a valve block, and the water flow rate of the two connecting pipes can be adjusted by moving the position of the valve block.

[0024] Optionally, the natural groundwater level simulation water supply device includes a PVC water pipe located above the water curtain tunnel simulation water injection device; the PVC water pipe includes multiple branch pipes distributed in an alternating manner, and the multiple branch pipes form a rectangular structure, with two water inlets set at opposite corners of the rectangular structure, and each branch pipe having a seepage hole on the side closest to the oil storage chamber.

[0025] Optionally, the grouting unit includes a second control cabinet, a first grouting pump, a second grouting pump, a grouting pipeline, a second flow sensor, and a second pressure sensor; the first grouting pump, the second grouting pump, the second flow sensor, and the second pressure sensor are respectively electrically connected to the second control cabinet;

[0026] The first grouting pump is connected to the first input end of the grouting pipe, and the second grouting pipe is connected to the second input end of the grouting pipe; the first input end and the second input end of the grouting pipe are each equipped with a second flow sensor and a second pressure sensor; the output end of the grouting pipe extends into the fracture zone of the oil storage cavern.

[0027] Optionally, the oil injection and production unit includes a first oil storage chamber, a second oil storage chamber, an oil inlet shaft, an oil outlet shaft, an oil pump, an oil tank, and a two-position three-way solenoid valve;

[0028] The first oil storage chamber is connected to the second oil storage chamber. The first oil storage chamber is connected to the oil outlet shaft, and the second oil storage chamber is connected to the oil inlet shaft. The oil inlet shaft, the oil outlet shaft, and the oil pump are respectively connected to the two-position three-way solenoid valve, and the oil pump is connected to the oil tank.

[0029] The oil pump can deliver oil from the oil storage chamber to the oil tank through the oil outlet riser, or it can deliver oil from the oil tank to the oil storage chamber through the oil inlet riser.

[0030] Optionally, the oil injection and production unit further includes a pump pit, a water pump, and a second water tank;

[0031] The pump pit is located in the lower part of the oil storage chamber corresponding to the oil outlet shaft. The input end of the water pump is connected to the pump pit, and the output end is connected to the second water tank.

[0032] Optionally, the oil injection and production unit further includes an upper connecting roadway and a lower connecting roadway;

[0033] The first oil storage cavern and the second oil storage cavern are connected by the upper connecting tunnel and the lower connecting tunnel, with the upper connecting tunnel located above the lower connecting tunnel.

[0034] Optionally, the oil injection and production unit further includes a third control cabinet, a third flow sensor, a third pressure sensor, and an oil level probe, wherein the third flow sensor and the third pressure sensor are electrically connected to the third control cabinet.

[0035] The third flow sensor and the third pressure sensor are installed on the oil pipeline connecting the oil inlet shaft and the two-position three-way solenoid valve;

[0036] The third flow sensor and the third pressure sensor are installed on the oil pipeline connecting the oil well to the two-position three-way solenoid valve;

[0037] The oil inlet shaft and the oil outlet shaft are respectively equipped with oil level probes, which are used to monitor the oil level position.

[0038] One technical advantage of this invention is that:

[0039] In this embodiment of the invention, the oil injection and production simulation test system for simulating underground reservoirs in water-sealed caverns is set up with four major sub-units: a tunnel excavation unit, a water injection unit, a grouting unit, and an oil injection and production unit. Firstly, it can change the layout and cross-sectional dimensions of the oil storage caverns according to actual working conditions. Secondly, it can dynamically simulate construction procedures such as underground reservoir excavation and grouting. Thirdly, it can change the groundwater boundary conditions and water curtain system settings to obtain parameters such as seepage pressure and inflow rate as a basis for evaluating the water seal effect. Fourthly, it can simulate the oil inflow and outflow within the water-sealed cavern. Thus, a systematic underground reservoir oil injection and production simulation test system is formed.

[0040] Moreover, the oil injection and production simulation test system for water-sealed underground reservoir simulation test is designed for the actual working conditions of oil injection and production in the field. It is equipped with water injection unit, grouting unit and oil injection and production unit. It not only highly simulates the oil injection and production operation process of underground reservoir, but also establishes highly similar stress-water curtain conditions, and truly restores the multi-field coupling occurrence conditions of water-force in underground rock mass. It realizes the simulation of water-sealed oil injection and production under complex working conditions with stress seepage multi-field coupling in underground reservoir.

[0041] In addition, the oil injection and production simulation test system for water-sealed underground reservoir simulation tests has been optimized to address the issue of variable seepage conditions in the surrounding rock fissures during underground water-sealed oil reservoir model tests. By using pump-filled grouting, the highly permeable water curtain boreholes and prefabricated fractured zones are sealed, thereby changing the permeability of the surrounding rock around the oil reservoir chamber. This simulates the entire process of grouting the surrounding rock fissures in the water-sealed oil reservoir chamber and can perform stability assessments on water-sealed oil reservoir models under different surrounding rock conditions and seepage conditions. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of an oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caves, according to an embodiment of the present invention.

[0043] Figure 2 This is a schematic diagram of the structure of a water curtain tunnel excavation device and a water curtain tunnel simulation water injection device in an oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caves, according to an embodiment of the present invention.

[0044] Figure 3 This is a schematic diagram of the water injection unit of an oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caves, according to an embodiment of the present invention.

[0045] Figure 4 This is a schematic diagram of the grouting unit of an oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caves, according to an embodiment of the present invention.

[0046] Figure 5This is a schematic diagram of the oil injection and production unit of an oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caves, according to an embodiment of the present invention.

[0047] In the diagram: 11. Oil storage cavern excavation device; 12. Water curtain tunnel excavation device; 2. Water injection unit; 21. Water curtain tunnel simulation water injection device; 211. Water curtain tunnel; 212. Pre-embedded thin pipe; 213. Connecting pipe; 214. T-joint; 215. Valve block; 22. Natural groundwater level simulation water supply device; 221. PVC water pipe; 222. Water inlet; 23. High-pressure water pump; 24. First water tank; 25. First control cabinet; 26. First pipeline; 27. Second pipeline; 28. First flow sensor; 29. ​​First pressure sensor; 3. Grouting unit; 31. Second control cabinet; 32. First injection... 33. Grouting pump; 34. Grouting pipeline; 35. Second flow sensor; 36. Second pressure sensor; 37. Switch valve; 4. Oil injection and production unit; 411. First oil storage chamber; 412. Second oil storage chamber; 413. Oil intake shaft; 414. Oil outlet shaft; 415. Oil pump; 416. Oil tank; 417. Two-position three-way solenoid valve; 418. Pump pit; 419. Water pump; 420. Second water tank; 421. Upper connecting roadway; 422. Lower connecting roadway; 423. Third control cabinet; 424. Third flow sensor; 425. Third pressure sensor; 5. Water-sealed reservoir model. Detailed Implementation

[0048] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0049] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0050] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0051] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0052] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0053] See Figures 1 to 5 As shown, this application provides an oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caverns. The system includes a tunnel excavation unit, a water injection unit 2, a grouting unit 3, and an oil injection and production unit 4. The water injection unit 2, grouting unit 3, and oil injection and production unit 4 constitute a water-sealed reservoir model 5. The tunnel excavation unit is used to excavate the oil storage cavern and the water curtain tunnel 211, and to monitor the data parameters of the excavation process of the oil storage cavern and the water curtain tunnel 211 in real time.

[0054] It should be noted that the water-sealed storage tank model 5 may include one or more oil storage caverns, and multiple oil storage caverns form an oil storage cavern group.

[0055] Specifically, the tunnel excavation unit includes an oil storage cavern excavation device 11 and a water curtain tunnel excavation device 12. The tunnel excavation unit is suitable for physical model tests of various cavern group types. The oil storage cavern excavation device 11 is used to excavate oil storage caverns of arbitrary shapes and can monitor the data parameters of the excavation process in real time. The water curtain tunnel excavation device 12 is pre-embedded along the excavation direction of the water curtain tunnel 211 to simulate the excavation process of the water curtain tunnel 211.

[0056] For example, the excavation process of oil storage caverns can be comprehensively controlled through an intelligent control cabinet for tunnel excavation.

[0057] See Figure 2The water curtain tunnel excavation device 12 is arranged sequentially along the excavation direction and pre-embedded to form a simulated long, straight water curtain channel at the oil storage chamber. The water curtain tunnel excavation device 12 includes a body, a screw, and wedge blocks, with the wedge blocks fixed to the body by the screw. For example, rotating the positive and negative threads at both ends of the screw can cause the wedge blocks to rise and fall along the inclined plane, allowing them to move towards or away from the body, thereby controlling the height of the entire water curtain tunnel excavation device 12. During testing, the water curtain tunnel excavation device 12 can be adjusted and adjusted sequentially along the excavation direction to simulate the entire process of excavating the water curtain tunnel 211.

[0058] The water injection unit 2 includes a water curtain tunnel simulation water injection device 21 and a natural groundwater level simulation water injection device 22; the water curtain tunnel simulation water injection device 21 and the natural groundwater level simulation water injection device 22 inject water simultaneously to simulate the superimposed water head pressure of the surrounding rock of the underground oil storage cavern under the natural groundwater level and the artificial water curtain tunnel 211.

[0059] Water injection unit 2 has the function of applying water pressure to any part inside the water-sealed reservoir model 5, thereby better realizing the seepage boundary conditions of the water-sealed reservoir model 5, so as to better carry out fluid-structure interaction simulation tests.

[0060] The grouting unit 3 is used to reinforce the fractured zone of the oil storage cavern with grout.

[0061] The oil injection and production unit 4 is used to suck in or discharge the oil stored in the oil storage cavern, and to control the flow rate and oil pressure of the stored oil.

[0062] In this embodiment of the invention, the oil injection and production simulation test system for simulating underground reservoirs in water-sealed caverns is set up with four major sub-units: a tunnel excavation unit, a water injection unit 2, a grouting unit 3, and an oil injection and production unit 4. Firstly, it can change the layout and cross-sectional dimensions of the oil storage caverns according to actual working conditions. Secondly, it can dynamically simulate construction procedures such as underground reservoir excavation and grouting. Thirdly, it can change the groundwater boundary conditions and water curtain system settings to obtain parameters such as seepage pressure and inflow rate as a basis for evaluating the water seal effect. Fourthly, it can simulate the oil inflow and outflow within the water-sealed cavern. Thus, a systematic underground reservoir oil injection and production simulation test system is formed.

[0063] Moreover, the oil injection and production simulation test system for water-sealed underground reservoir simulation test is designed for the actual on-site oil injection and production working environment. It is equipped with water injection unit 2, grouting unit 3 and oil injection and production unit 4. It not only highly simulates the oil injection and production operation process of underground reservoir, but also establishes highly similar stress-water curtain conditions, and truly restores the multi-field coupling occurrence conditions of water-force in the underground rock mass. It realizes the simulation of water-sealed oil injection and production under complex working conditions with stress seepage multi-field coupling in underground reservoir.

[0064] In addition, the oil injection and production simulation test system for water-sealed underground reservoir simulation tests has been optimized to address the issue of variable seepage conditions in the surrounding rock fissures during underground water-sealed oil reservoir model tests. By using pump-filled grouting, the highly permeable water curtain boreholes and prefabricated fractured zones are sealed, thereby changing the permeability of the surrounding rock around the oil reservoir chamber. This simulates the entire process of grouting the surrounding rock fissures in the water-sealed oil reservoir chamber and can perform stability assessments on water-sealed oil reservoir models under different surrounding rock conditions and seepage conditions.

[0065] Optionally, the oil storage cavern excavation device 11 includes multiple tunnel contour frames, each with a different shape;

[0066] The oil storage cavern excavation device 11 is placed directly in front of the oil storage cavern to be excavated.

[0067] In the above embodiments, the oil storage cavern excavation device 11 can realize the automatic control excavation of any cavern shape and the real-time monitoring of excavation process data parameters. The excavation process is easy to control and is suitable for the excavation of oil storage caverns of various shapes, with a wide range of applications.

[0068] Optionally, see Figure 3 The water injection unit 2 includes a high-pressure water pump 23, a first water tank 24, a first control cabinet 25, a first pipeline 26, a second pipeline 27, a first flow sensor 28, and a first pressure sensor 29; wherein the high-pressure water pump 23, the first flow sensor 28, and the first pressure sensor 29 are electrically connected to the first control cabinet 25.

[0069] The input end of the high-pressure water pump 23 is connected to the first water tank 24, the first output end is connected to the water curtain tunnel simulation water injection device 21 through the first pipeline 26, and the second output end is connected to the natural groundwater level simulation water filling device 22 through the second pipeline 27.

[0070] The first flow sensor 28 and the first pressure sensor 29 are both installed on the first pipeline 26 and the second pipeline 27.

[0071] In the above embodiment, the first control cabinet 25 can control the amount of water pumped from the first water tank 24 by adjusting the motor speed of the high-pressure water pump 23. The water in the first water tank 24 is pumped by the high-pressure water pump 23 through the first pipeline 26 to the water curtain tunnel 211 of the water curtain tunnel simulation water injection device 21, or through the second pipeline to the PVC water pipe 221 of the natural groundwater level simulation water filling device 22. Then, after the water flows into the water curtain tunnel 211, it can permeate to the surroundings through horizontal or vertical boreholes. The first pipeline 26 and the second pipeline 27 are both equipped with the first flow sensor 28 and the first pressure sensor 29, which can detect the pressure and flow in the first or second pipeline in real time and immediately feed back to the first control cabinet 25. The first control cabinet 25 further adjusts the motor speed of the high-pressure water pump 23 based on the feedback information.

[0072] Optionally, the water curtain tunnel simulation water injection device 21 includes two water curtain tunnels 211, which are located on opposite sides above the oil injection and production unit 4.

[0073] Multiple rows of pre-embedded thin pipes 212 are arranged along the depth of the water curtain tunnel 211. The pre-embedded thin pipes are provided with drill holes, and a water curtain surrounding the oil storage cavern is formed through the drill holes.

[0074] Each of the water curtain tunnels 211 is connected to a connecting pipe 213, and the two connecting pipes 213 are connected to the first pipeline 26 through a three-way connector 214;

[0075] The tee connector 214 is equipped with a valve block 215, and the water flow rate of the two connecting pipes 213 can be adjusted by moving the position of the valve block 215.

[0076] In the above embodiment, two water curtain tunnels 211 are arranged longitudinally side by side in the upper part of the oil storage cavern group using a pre-embedded strip method. Multiple rows of pre-embedded thin pipes 212 are arranged circumferentially along the depth direction of the water curtain tunnels 211. The pre-embedded thin pipes 212 are provided with connecting boreholes that form the water curtain tunnels 211, so as to form a long straight annular water curtain covering and surrounding the oil storage cavern group. The acrylic glass close to the front end of the water curtain tunnel 211 is perforated to connect with the connecting pipe 213. The connecting pipe 213, the first pipeline 26, the high-pressure water pump 23, the valve block 215, the first flow sensor 28, the first pressure sensor 29, the first control cabinet 25, and the first water tank 24 together form the water injection control circuit of the water curtain.

[0077] For example, valves are installed on both sides of the three-way connector 214. By operating the valves, the water flow into the two water curtain tunnels 211 can be shut off at any time, which is very convenient.

[0078] Therefore, the structural design of the water curtain tunnel simulation water injection device 21 is reasonable and can simulate real working conditions to perform good water injection simulation.

[0079] Optionally, the natural groundwater level simulation water injection device 22 includes a PVC water pipe 221, which is located above the water curtain tunnel simulation water injection device 21. The PVC water pipe 221 includes multiple branch pipes that are distributed in an alternating manner, and the multiple branch pipes form a rectangular structure. Two water inlets 222 are provided at the diagonal of the rectangular structure, and each branch pipe has a seepage hole on the side closer to the oil storage chamber.

[0080] In one specific implementation, the PVC water pipe 221 is arranged in a multi-way interconnected manner to form multiple staggered branch pipes. Seepage holes are evenly distributed on the side of each branch pipe closest to the oil storage chamber. Water inlets 222 are located at the far diagonal points of the rectangular structure, and these inlets are connected to an external water injection hose. The PVC water pipe 221, the second pipeline 27, the high-pressure water pump 23, the first flow sensor 28, the first pressure sensor 29, the first control cabinet 25, and the first water tank 24 together form a water injection control circuit for the natural groundwater level. This effectively simulates the uniform seepage process of the natural groundwater level, highly replicating the geological environment of the cavern storage. It can simulate water replenishment / non-replenishment according to experimental requirements, and the water volume can be controlled by the first flow sensor 28 to achieve precise adjustment of water pressure and volume. The entire water injection unit 2 is simple to operate, safe, reliable, practical, and efficient.

[0081] Optionally, see Figure 4 The grouting unit 3 includes a second control cabinet 31, a first grouting pump 32, a second grouting pump 33, a grouting pipe 34, a second flow sensor 35, and a second pressure sensor 36; the first grouting pump 32, the second grouting pump 33, the second flow sensor 35, and the second pressure sensor 36 are electrically connected to the second control cabinet 31 respectively.

[0082] The first grouting pump 32 is connected to the first input end of the grouting pipe 34, and the second grouting pipe 34 is connected to the second input end of the grouting pipe 34; the first input end and the second input end of the grouting pipe 34 are each provided with a second flow sensor 35 and a second pressure sensor 36; the output end of the grouting pipe 34 extends into the fracture zone of the oil storage cavern.

[0083] In the above embodiment, the grouting unit 3 consists of a second control cabinet 31, a first grouting pump 32, a second grouting pump 33, a grouting pipe 34, a second flow sensor 35, and a second pressure sensor 36. The grouting unit 3 can perform grouting reinforcement of fractured zones such as tunnel cracks and fissures, and achieve grouting under certain pressure conditions through the small first grouting pump 32 and the second grouting pump 33.

[0084] In the simulation test, a prefabricated fractured zone was constructed, filled with large-sized gravel to increase permeability. This fractured zone was connected to a pre-embedded thin-slot pipe 212, which was part of a simulated water curtain borehole. A switch valve 37 was installed on the pre-embedded thin-slot pipe 212 to better control the water injection process. The grouting pipeline was directly connected to the fractured zone via prefabricated holes in the outer frame of the water-sealed reservoir model 5, used for grouting the pre-embedded fractured zone. The grouting pipeline was also directly connected to the fractured zone and the water curtain connecting borehole via prefabricated holes in the outer frame of the water-sealed reservoir model 5. The external pipeline was sequentially connected to the grouting pipe 34, the second flow sensor 35, the second pressure sensor 36, the first grouting pump 32, the second grouting pump 33, and the second control cabinet 31, together forming a grouting simulation control system to realize the fracture grouting process in the water-sealed oil depot model test.

[0085] It should be noted that the grouting simulation process is as follows:

[0086] (1) Water-rich fracture formation stage: Open the switch valve 37 on the pre-embedded fine flower pipe 212 to simulate water injection into the water curtain tunnel 211 and form an artificial water curtain. During this process, water seeps into the prefabricated fracture zone through the pre-embedded fine flower pipe 212 and the surrounding rock pores, so that the fracture zone forms a water-rich state.

[0087] (2) Grouting stage of fracture zone: Close the switch valve 37 on the pre-embedded fine flower pipe 212, and add different grouting materials (liquid A and liquid B) of the first grouting pump 32 and the second grouting pump 33 into the storage tanks of the first grouting pump 32 and the second grouting pump 33 respectively. Set the grouting parameters through the data sensing and the control system of the second control cabinet 31, and start the first grouting pump 32 and the second grouting pump 33. After mixing liquid A and liquid B through the three-way valve, they are injected into the fracture zone through the grouting pipeline. The grouting flow rate and grouting pressure test data are sensed through the data sensing and the control system of the second control cabinet 31.

[0088] (3) Grouting control end stage: When the grouting pressure reaches the final grouting pressure, the grouting system automatically stops grouting, closes the switch valve on the grouting pipeline, dismantles the grouting system, cleans the grouting pipeline and grouting pump, and completes the grouting.

[0089] Therefore, the grouting unit 3 has a reasonable structural design and can effectively grout the fractured zone of the water-sealed oil tunnel model. The operation is very simple.

[0090] Optionally, such as Figure 5As shown, the oil injection and production unit 4 includes a first oil storage chamber 411, a second oil storage chamber 412, an oil inlet shaft 413, an oil outlet shaft 414, an oil pump 415, an oil tank 416, and a two-position three-way solenoid valve 417. The oil injection and production unit 4 can realize the intake and discharge of oil stored in the water-sealed oil cavern, simulating the oil injection and production conditions of an oil storage chamber group in real-world working conditions.

[0091] The first oil storage chamber 411 is connected to the second oil storage chamber 412. The first oil storage chamber 411 is connected to the oil outlet shaft 414, and the second oil storage chamber 412 is connected to the oil inlet shaft 413. The oil inlet shaft 413, the oil outlet shaft 414, and the oil pump 415 are respectively connected to the two-position three-way solenoid valve 417, and the oil pump 415 is connected to the oil tank 416.

[0092] The oil pump 415 can deliver the oil pump 415 in the oil storage cavern to the oil tank 416 through the oil outlet vertical pipe, or it can deliver the oil pump 415 in the oil tank 416 to the oil storage cavern through the oil inlet vertical pipe.

[0093] In the above embodiment, the oil inlet shaft 413 and the oil outlet shaft 414 are arranged side by side at the front end of the oil storage chamber by pre-embedding. Both adopt a telescopic sleeve design, with the outer cylinder fixed in the oil storage chamber and the inner cylinder telescopically set inside the outer cylinder. The end of the inner cylinder is provided with an oil level probe and a probe fixing plate. The oil level probe can be firmly fixed on the inner cylinder through the probe fixing plate, so as to monitor the oil position in real time and facilitate the control of oil injection flow and oil pressure.

[0094] Optionally, the oil injection and production unit 4 further includes a pump pit 418, a water pump 419, and a second water tank 420;

[0095] The pump pit 418 is located in the lower part of the oil storage chamber corresponding to the oil outlet shaft 414. The input end of the water pump 419 is connected to the pump pit 418, and the output end is connected to the second water tank 420.

[0096] In the above embodiment, the pump pit 418 is located in the lower part of the cavern corresponding to the oil well 414, and is connected to the water pump 419 through a soft water pipe. It can extract the water that has seeped into the cavern after water-oil separation, adjust the water-oil ratio and oil level, and is easy to operate.

[0097] Optionally, see Figure 5 The oil injection and production unit 4 also includes an upper connecting roadway 421 and a lower connecting roadway 422;

[0098] The first oil storage chamber 411 and the second oil storage chamber 412 are connected by the upper connecting tunnel 421 and the lower connecting tunnel 422, with the upper connecting tunnel 421 located above the lower connecting tunnel 422.

[0099] Both the upper connecting tunnel 421 and the lower connecting tunnel 422 are located at the rear end of the oil storage chamber. Both the upper connecting tunnel 421 and the lower connecting tunnel 422 are visible connecting pipes, and the connections between the upper connecting tunnel 421 and the lower connecting tunnel 422 and the first oil storage chamber 411 and the second oil storage chamber 412 are sealed.

[0100] The upper connecting tunnel 421 and the lower connecting tunnel 422 can effectively connect the first oil storage chamber 411 and the second oil storage chamber 412, that is, to form a connecting passage between the oil storage chamber group, which is conducive to the intake and discharge of oil stored in the water-sealed oil tunnel.

[0101] Optionally, the oil injection and production unit 4 further includes a third control cabinet 423, a third flow sensor 424, a third pressure sensor 425, and an oil level probe. The third flow sensor 424 and the third pressure sensor 425 are electrically connected to the third control cabinet 423, respectively.

[0102] The third flow sensor 424 and the third pressure sensor 425 are installed on the oil pipeline connecting the oil inlet shaft 413 and the two-position three-way solenoid valve 417.

[0103] The third flow sensor 424 and the third pressure sensor 425 are installed on the oil pipeline connecting the oil well 414 and the two-position three-way solenoid valve 417.

[0104] The oil inlet shaft 413 and the oil outlet shaft 414 are respectively equipped with oil level probes, which are used to monitor the oil level position.

[0105] In the above embodiment, the top ports of the inlet shaft 413 and the outlet shaft 414 are equipped with sealing sleeves that are nested with the oil pipelines. A high-flow, normally open two-position three-way valve, an oil pump 415, and an oil tank 416 are connected in series. The oil pump 415 is a gear pump. During the test, the oil delivery path of the oil pump 415 can be adjusted via the two-position three-way valve to complete the oil injection and production process into the oil storage chamber. The operation is simple and facilitates control of the oil injection and production process.

[0106] It should be noted that the oil injection and production unit 4 includes an information acquisition and control module, comprising: a third flow sensor 424, a third pressure sensor 425, and an oil level probe, all of which are part of the information acquisition and control module. The third flow sensor 424 and the third pressure sensor 425 are installed along the oil pipeline path, while the oil level probe is located at the end of the inner cylinder and connected to the inner cylinder via a probe fixing plate and screws. The third pressure sensor 425 can monitor the oil pressure in real time, and the oil level probe can monitor the oil position, facilitating the control of oil injection flow and pressure. Therefore, the third control cabinet 423 integrates the control elements and wiring for the third flow sensor 424, the third pressure sensor 425, and the oil level probe, enabling control of the normal operation of each component and visual analysis of information data acquisition.

[0107] It should be noted that the simulation process for oil injection and production is as follows:

[0108] (1) Preparation stage: The water curtain tunnel simulation water injection device 21 injects water into the area around the oil storage cavern, so that the pores of the surrounding rock model around the oil storage cavern are filled with water, and the water level of the water seeping into the oil storage cavern reaches the scale line.

[0109] (2) Oil injection stage: Open the two-position three-way solenoid valve 417, and the oil pump 415 rotates in the forward direction to draw oil from the oil tank 416 and pump it into the oil inlet shaft 413. Then, the oil enters the first oil storage chamber 411 through the upper connecting roadway 421 and the lower connecting roadway 422 in the second oil storage chamber 412. Use the oil level probe to sense the oil level in the oil storage chamber and complete the oil injection process.

[0110] (3) Oil pumping stage: Close the two-position three-way solenoid valve 417, and the oil pump 415 rotates in the reverse direction to pump oil from the oil outlet shaft 414 into the oil tank 416, thus completing the oil pumping process.

[0111] In this embodiment, the water-sealed reservoir model 5 is used to simulate a real underground reservoir; the tunnel excavation unit is used to simulate the entire process of excavating the oil storage cavern and the water curtain tunnel 211; the water injection unit 2 injects water into the reservoir model through the water injection port to simulate the superimposed stable water head pressure of the surrounding rock of the underground reservoir under the natural groundwater level and the artificial water curtain tunnel 211, thereby realizing the seepage boundary conditions of the model; the grouting unit 3 can realize the grouting reinforcement of fracture zones such as tunnel cracks and fissures, and realize grouting under certain pressure conditions through a small grouting pump; the oil injection and production unit 4 can realize the intake and discharge of oil stored in the water-sealed oil cavern, simulating the oil injection and production conditions of the oil storage cavern group in real working conditions.

[0112] Therefore, the oil injection and production simulation test system provided in this application for simulating underground reservoirs in water-sealed rock caverns can physically simulate the oil injection and production operation status of underground reservoirs, such as reservoir cavern excavation, natural groundwater level simulation, surrounding rock fissure grouting, and water sealing of the oil injection and production tank, based on actual working conditions, thus forming a systematic underground reservoir oil injection and production simulation test system.

[0113] In summary, the oil injection and production simulation test system used for the simulation test of underground reservoirs in water-sealed rock caves is reasonably designed, can accurately simulate the seepage state of the surrounding rock of the cavern, and has good universality.

[0114] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. An oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caverns, characterized in that, include: The tunnel excavation unit includes an oil storage cavern excavation device and a water curtain tunnel excavation device. The oil storage cavern excavation device is used to excavate oil storage caverns of any shape and can monitor the data parameters of the excavation process in real time. The water curtain tunnel excavation device is pre-embedded along the excavation direction of the water curtain tunnel to simulate the excavation process of the water curtain tunnel. The water injection unit includes a water curtain tunnel simulation water injection device and a natural groundwater level simulation water filling device; the water curtain tunnel simulation water injection device and the natural groundwater level simulation water filling device inject water simultaneously to simulate the superimposed water head pressure of the surrounding rock of the underground oil storage cavern at the natural groundwater level and the artificial water curtain tunnel. Grouting unit, the grouting unit is used to grout and reinforce the fractured zone of the oil storage cavern; The oil injection and production unit is used to suck in or discharge oil stored in the oil storage cavern, and to control the flow rate and oil pressure of the stored oil. The water injection unit includes a high-pressure water pump, a first water tank, a first control cabinet, a first pipeline, a second pipeline, a first flow sensor, and a first pressure sensor; wherein the high-pressure water pump, the first flow sensor, and the first pressure sensor are electrically connected to the first control cabinet. The input end of the high-pressure water pump is connected to the first water tank, the first output end is connected to the water curtain tunnel simulation water injection device through the first pipeline, and the second output end is connected to the natural groundwater level simulation water filling device through the second pipeline. The first flow sensor and the first pressure sensor are both installed on the first pipeline and the second pipeline; The water curtain tunnel simulation water injection device includes two water curtain tunnels, which are located on opposite sides above the oil injection and production unit. Multiple rows of pre-embedded thin pipes are arranged along the depth of the water curtain tunnel. The pre-embedded thin pipes are equipped with drill holes, which form a water curtain surrounding the oil storage cavern. Each of the water curtain tunnels is connected to a connecting pipe, and the two connecting pipes are connected to the first pipeline through a T-joint. The tee joint is equipped with a valve block, and the water flow rate of the two connecting pipes can be adjusted by moving the position of the valve block; The natural groundwater level simulation water supply device includes a PVC water pipe located above the water curtain tunnel simulation water injection device. The PVC water pipe includes multiple branch pipes that are staggered and form a rectangular structure. Two water inlets are set at the diagonal of the rectangular structure, and each branch pipe has a seepage hole on the side closer to the oil storage chamber.

2. The oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caverns according to claim 1, characterized in that, The oil storage cavern excavation device includes multiple tunnel contour frames, each with a different shape. The oil storage cavern excavation device is placed directly in front of the oil storage cavern to be excavated.

3. The oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caverns according to claim 1, characterized in that, The grouting unit includes a second control cabinet, a first grouting pump, a second grouting pump, grouting pipes, a second flow sensor, and a second pressure sensor; the first grouting pump, the second grouting pump, the second flow sensor, and the second pressure sensor are electrically connected to the second control cabinet respectively; The first grouting pump is connected to the first input end of the grouting pipe, and the second grouting pump is connected to the second input end of the grouting pipe; the first input end and the second input end of the grouting pipe are each equipped with a second flow sensor and a second pressure sensor; the output end of the grouting pipe extends into the fracture zone of the oil storage cavern.

4. The oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caverns according to claim 1, characterized in that, The oil injection and production unit includes a first oil storage chamber, a second oil storage chamber, an oil intake shaft, an oil outlet shaft, an oil pump, an oil tank, and a two-position three-way solenoid valve; The first oil storage chamber is connected to the second oil storage chamber. The first oil storage chamber is connected to the oil outlet shaft, and the second oil storage chamber is connected to the oil inlet shaft. The oil inlet shaft, the oil outlet shaft, and the oil pump are respectively connected to the two-position three-way solenoid valve, and the oil pump is connected to the oil tank. The oil pump can pump oil from the oil storage chamber to the oil tank through the oil outlet shaft, or pump oil from the oil tank to the oil storage chamber through the oil inlet shaft.

5. The oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caverns according to claim 4, characterized in that, The oil injection and production unit also includes a pump pit, a water pump, and a second water tank; The pump pit is located in the lower part of the oil storage chamber corresponding to the oil outlet shaft. The input end of the water pump is connected to the pump pit, and the output end is connected to the second water tank.

6. The oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caverns according to claim 5, characterized in that, The oil injection and production unit also includes an upper connecting roadway and a lower connecting roadway; The first oil storage cavern and the second oil storage cavern are connected by the upper connecting tunnel and the lower connecting tunnel, with the upper connecting tunnel located above the lower connecting tunnel.

7. The oil injection and production simulation test system for simulating underground reservoirs in water-sealed rock caverns according to claim 6, characterized in that, The oil injection and production unit also includes a third control cabinet, a third flow sensor, a third pressure sensor, and an oil level probe. The third flow sensor and the third pressure sensor are electrically connected to the third control cabinet. The third flow sensor and the third pressure sensor are installed on the oil pipeline connecting the oil inlet shaft and the two-position three-way solenoid valve; The third flow sensor and the third pressure sensor are installed on the oil pipeline connecting the oil well to the two-position three-way solenoid valve; The oil inlet shaft and the oil outlet shaft are respectively equipped with oil level probes, which are used to monitor the oil level position.

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