An experimental device for simulating reservoir sand production under injection and production conditions in an oil and gas reservoir.

Abstract

This invention relates to the field of oil and gas exploration and development, and particularly to a reservoir sand production simulation experimental device under injection and production conditions in an oil and gas reservoir. The device includes a core holder for holding cores used in the experiment; gas and liquid supply equipment; a temperature control device; an axial pressure loading device for applying axial pressure to the cores within the core holder; a confining pressure loading device for applying confining pressure to the cores within the core holder; a gas-liquid-solid separation device connected to the output end of the core holder for performing solid-liquid-gas analysis on the sand products discharged from the core holder; and a sand production monitoring device for monitoring the critical point and critical time of sand production. This invention can simulate reservoir sand production under different downhole gas and liquid injection / production conditions; it can simulate the influence of different production pressure differentials and different gas volumes on formation sand production; and it can accurately record the critical point of sand production, sand production volume, and sand rate.

Description

Technical Field

[0001] This invention relates to the field of oil and gas exploration and development, and in particular to a simulated experimental device for reservoir sand production under injection and production conditions in an oil and gas reservoir-type gas storage facility. Background Technology

[0002] Unlike ordinary oil and gas wells, injection and production wells in oil and gas reservoir-type gas storage facilities are characterized by long service life, ability to withstand alternating loads, and high requirements for gas sealing. Currently, drilling and completion engineering technologies mainly used for oil and gas field development can no longer meet the special needs of gas storage facilities. The overall single-well injection and production capacity of existing oil and gas reservoir-type gas storage facilities is relatively small, which cannot fully utilize the emergency peak-shaving function of gas storage facilities. Reservoir contamination during the drilling and completion process reduces the single-well injection and production capacity, and unsuitable completion methods fail to fully utilize the reservoir's capacity.

[0003] Currently, sandstone formations are the most common reservoirs in oil and gas reservoirs. Under gas production conditions, some injection and production wells in these reservoirs experience severe sand production problems. Uncontrolled sand production can significantly impact the gas production rate per well, thus limiting the overall gas production efficiency of the reservoir. Therefore, to select appropriate well completion methods, develop suitable production plans, and improve the gas production rate per well, it is necessary to evaluate the sand production situation in sandstone reservoirs.

[0004] In existing technologies, due to the complexity of sandstone reservoirs, it is impractical to collect data on sand production from sandstone reservoirs. Therefore, there is an urgent need for an experimental system that can simulate the sand production of sandstone reservoirs in gas storage facilities. This system would simulate the sand production of sandstone formations in gas storage facilities through indoor experiments, thereby providing a theoretical basis for the actual gas injection and production process and the selection of well completion methods in gas storage injection and production wells. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a reservoir sand production simulation experimental device under the injection and production conditions of an oil and gas reservoir. It can simulate the reservoir sand production under different injection and production gas volumes and different liquid volumes in the well of an oil and gas reservoir, and can accurately record the sand production critical point, sand production volume and sand production rate, and obtain the critical parameters of sand production in the gas reservoir, so as to provide a theoretical basis for the actual gas injection and production process and the selection of well completion methods in the gas reservoir.

[0006] The technical solution of this invention to solve the above-mentioned technical problems is as follows: A simulation experimental device for reservoir sand production under injection and production conditions in an oil and gas reservoir, comprising...

[0007] A core holder for holding cores used in experiments;

[0008] A gas supply device and a liquid supply device, both of which are connected to the input end of the core holder, are used to supply a mixed fluid into the core holder;

[0009] A temperature control device, wherein the temperature control device is used to control the temperature of the fluid supplied by the gas supply device and the liquid supply device;

[0010] An axial compression loading device, which is connected to the core holder, is used to apply axial compression to the core inside the core holder;

[0011] A confining pressure loading device, which is connected to the core holder, is used to apply confining pressure to the core inside the core holder;

[0012] A gas-liquid-solid separation device, wherein the gas-liquid-solid separation device is connected to the output end of the core holder, and is used to perform solid-liquid-gas analysis on the sand products discharged from the core holder;

[0013] A sand discharge monitoring device is installed between the core holder and the gas-liquid-solid separation device to monitor the critical point and critical time of sand discharge from the core.

[0014] The beneficial effects of this invention are: it can simulate reservoir sand production under different downhole gas injection and production rates and liquid volumes; it can simulate the impact of alternating injection and production conditions in the gas storage facility on formation sand production; it can simulate the impact of different production pressure differentials and different gas volumes on formation sand production; and it can accurately record the critical point of sand production, sand production volume, and sand production rate.

[0015] Based on the above technical solution, the present invention can be further improved as follows.

[0016] Furthermore, the core holder includes a cylindrical body. Internal threads are provided on the inner walls of both ends of the cylindrical body. A left pressure cap and a right pressure cap are respectively provided inside each end of the cylindrical body. Both the left and right pressure caps are threadedly connected to the inner walls of the cylindrical body. Tapered sleeves are fixedly provided on the opposite ends of the left and right pressure caps. A rubber sleeve is provided between the two tapered sleeves. The two ends of the rubber sleeve are respectively pressed and fixed to the inner walls of the cylindrical body by the two tapered sleeves. A confining pressure cavity is formed between the middle of the rubber sleeve and the inner wall of the cylindrical body at an interval. A confining pressure port communicating with the confining pressure cavity is provided on the cylindrical body. The confining pressure port is connected to the confining pressure loading device. A small pressure cap is fixedly provided inside the left pressure cap. An axial pressure cylinder is sealed and fixedly connected to the end of the cylindrical body with the right pressure cap. A cap is integrally fixedly provided at the end of the axial pressure cylinder away from the cylindrical body. A steering piston is slidably provided on the inner side of the axial pressure cylinder. One end of the steering piston passes through and extends out of the cover and is slidably and sealingly connected to the cover. An axial pressure port communicating with the inside of the axial pressure cylinder is provided near the cover. The output end of the axial pressure loading device is connected to the axial pressure port for injecting fluid into the axial pressure cylinder to drive the steering piston to move along the axial direction of the axial pressure cylinder. Core plugs are provided on the sides of the small pressure cap and the steering piston facing each other. A core chamber is formed between the two core plugs. One core plug is provided with an inlet channel penetrating both ends of the core plug. The other core plug is provided with an outlet channel penetrating both ends of the core plug. The inlet channel is connected to the gas supply device and the liquid supply device. The outlet channel is connected to the gas-liquid-solid separation device.

[0017] The beneficial effects of adopting the above-mentioned further scheme are as follows: the core is placed in the core chamber, and pressure is applied to the confining pressure chamber through the confining pressure loading device to achieve confining pressure loading on the core. Pressure is applied to the axial pressure cylinder through the axial pressure loading device, which drives the steering piston to move, thereby driving the core plug connected to the steering piston to move and applying a certain axial pressure to the core. The gas supply device and the liquid supply device provide the core with a mixed fluid with a certain flow rate, pressure and a certain gas-liquid ratio. After passing through the core, the mixed fluid carries a certain amount of discrete sand into the solid-liquid separation device to simulate the influence of different production pressure differentials, different gas volumes and different liquid volumes on formation sand production.

[0018] Furthermore, the inlet channel is connected to one end of the first inlet pipe, the other end of the first inlet pipe is connected to the output port of the first valve, the input port of the first valve is connected to the gas supply device and the output port of the liquid supply device through the second inlet pipe, the outlet channel is connected to one end of the first outlet pipe, the other end of the first outlet pipe is connected to the input port of the second valve, the output port of the second valve is connected to one end of the second outlet pipe, the other end of the second outlet pipe is connected to the input port of the gas-liquid-solid separation device, the two ports of the third valve are respectively connected to the second inlet pipe and the first outlet pipe through pipes, and the two ports of the fourth valve are respectively connected to the first inlet pipe and the second outlet pipe through pipes.

[0019] The beneficial effects of adopting the above-mentioned further scheme are as follows: by adjusting the opening and closing of the first valve, the second valve, the third valve, and the fourth valve, the forward drive and directional drive of the fluid can be realized. When the first valve and the second valve are opened and the third valve and the fourth valve are closed, the fluid input from the second inlet pipe passes through the first valve, the first inlet pipe, the core cavity, the first outlet pipe, the second valve, and the second outlet pipe in sequence before entering the gas-liquid-solid separation equipment. When the third valve and the fourth valve are opened and the first valve and the second valve are closed, the fluid input from the second inlet pipe passes through the third valve, the first outlet pipe, the core cavity, the first inlet pipe, the fourth valve, and the second outlet pipe in sequence before entering the gas-liquid-solid separation equipment.

[0020] Furthermore, an annular seat is integrally fixed on the outer wall of the steering piston, and the outer wall of the annular seat is slidably connected to the inner wall of the axial pressure cylinder. The axial pressure port is located between the cover and the annular seat.

[0021] The beneficial effect of adopting the above-mentioned further solution is that the setting of the annular seat protruding from the outer wall of the steering piston creates a cavity between the annular seat and the cover, so that the axial pressure loading device can inject gas or liquid to pressurize and push the annular seat to move, thereby driving the steering piston to move.

[0022] Furthermore, an annular groove is provided on the peripheral wall of the annular seat, and a sealing ring assembly is provided in the annular groove.

[0023] The beneficial effect of adopting the above-mentioned further solution is that by setting an annular groove and setting a sealing ring assembly in the annular groove, the sealing performance between the peripheral wall of the annular seat and the inner wall of the axial pressure cylinder is ensured.

[0024] Furthermore, the two core plugs have a star-shaped groove and / or multiple annular grooves on the side facing each other.

[0025] The beneficial effect of adopting the above-mentioned further scheme is that the setting of the star-shaped groove and / or multiple annular grooves can increase the contact area between the mixed fluid and the core cross section.

[0026] Furthermore, the gas supply equipment includes a gas compressor, a piston container, and a constant speed and constant pressure pump. The first end of the piston container is connected to a multi-way valve. The output end of the gas compressor is connected to one port of the multi-way valve through a pipe. The second end of the piston container is connected to the output end of the constant speed and constant pressure pump through a pipe. The input end of the constant speed and constant pressure pump is connected to a water tank through a pipe. A piston is provided in the middle of the piston container. The other port of the multi-way valve is connected to the input end of the core holder through a pipe.

[0027] The beneficial effects of adopting the above-mentioned further scheme are as follows: the gas compressor provides compressed gas through the pipeline into the piston container, causing the piston in the piston container to move and store a certain amount of compressed gas. Then, the port connected to the gas compressor of the multi-way valve is closed, and the port connected to the core holder of the multi-way valve is opened. Liquid is injected into the piston container by a constant speed and constant pressure pump, which pushes the piston to move, thereby allowing the gas to be injected into the core holder at a constant flow rate.

[0028] Furthermore, the piston is connected to a displacement sensor for detecting the displacement of the piston within the piston container.

[0029] The beneficial effect of adopting the above-mentioned further solution is that the displacement sensor can accurately measure the piston's movement distance in real time, further ensuring the constant flow of gas injection.

[0030] Furthermore, the piston container includes a piston cylinder, the piston is disposed inside the piston cylinder, and the peripheral wall of the piston is slidably connected to the inner wall of the piston cylinder in a sealing manner. Piston plugs are provided at both ends inside the piston cylinder, and piston caps for confining the piston plugs inside the piston cylinder are fixedly provided at both ends of the piston cylinder. One end of each of the two piston plugs passes through and extends out of the two piston caps respectively. Flow channels are provided on the piston plugs, penetrating both ends of the piston plugs. The two flow channels are respectively connected to one port of the multi-way valve and the output end of the constant speed and constant pressure pump.

[0031] The beneficial effect of adopting the above-mentioned further solution is that by sealing the piston plug inside both ends of the piston cylinder with the pressure cap, it is convenient for the piston to be placed inside the piston cylinder and for the entire piston container to be assembled.

[0032] Furthermore, the gas-liquid-solid separation equipment includes a solid-liquid separation device, a gas-liquid separation device, and a sand collection device. The input end of the solid-liquid separation device is connected to the output end of the core holder. The sand collection device is connected to the solid output port of the solid-liquid separation device. The input end of the gas-liquid separation device is connected to the liquid output port of the solid-liquid separation device. A wet flow meter is provided at the gas output port of the gas-liquid separation device.

[0033] The beneficial effects of adopting the above-mentioned further scheme are as follows: the solid-liquid separation device is used to separate sand in the mixed fluid, the sand collection device can measure the sand output in real time, and then record the total time used by the sand discharge equipment to discharge discrete sand, and determine the sand output rate based on the total mass and total time; the gas-liquid separation device is connected after the solid-liquid separation device to separate gas and liquid in the mixed fluid, wherein the gas flow rate is measured by a wet flow meter, and the core permeability can be determined based on the inlet and outlet flow rates of the sand discharge equipment. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of the present invention;

[0035] Figure 2 This is a schematic diagram of the core holder of the present invention;

[0036] Figure 3 This is a schematic diagram of the end face structure of the core plug in this invention;

[0037] Figure 4 This is a schematic diagram of the gas supply device in this invention;

[0038] Figure 5 This is a schematic diagram of the piston container in this invention.

[0039] The attached diagram lists the components represented by each number as follows:

[0040] 1. Core holder; 1-1. Cylinder; 1-2. Left pressure cap; 1-3. Right pressure cap; 1-4. Tapered sleeve; 1-5. Rubber sleeve; 1-6. Confining pressure chamber; 1-7. Confining pressure port; 1-8. Small pressure cap; 1-9. Axial pressure cylinder; 1-10. Cover; 1-11. Steering piston; 1-12. Axial pressure port; 1-13. Core plug; 1-14. Core chamber; 1-15. Inlet channel; 1-16. Outlet channel; 1-17. Annular seat; 1-18. Annular groove; 1-19. Sealing ring assembly; 1-20. Star-shaped groove; 1-21. Annular groove; 1-22. Pad; 2. Gas supply equipment; 2-1. Gas compressor; 2-2. Piston container; 2-3. Constant speed and constant pressure 1. Pump; 2-4. Multi-way valve; 2-5. Water tank; 2-6. Piston; 2-7. Displacement sensor; 2-8. Piston cylinder; 2-9. Piston plug; 2-10. Piston cap; 2-11. Flow channel; 2-12. Annular groove; 2-13. Concave surface; 3. Liquid supply equipment; 4. Temperature control equipment; 5. Axial pressure loading equipment; 6. Confining pressure loading equipment; 7. Sand discharge monitoring equipment; 8. Solid-liquid separation device; 9. Gas-liquid separation device; 10. Sand collection device; 11. Wet flow meter; 12. First inlet pipe; 13. First valve; 14. Second inlet pipe; 15. First outlet pipe; 16. Second valve; 17. Second outlet pipe; 18. Third valve; 19. Fourth valve. Detailed Implementation

[0041] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0042] like Figure 1 As shown, an embodiment of the present invention includes a core holder 1 for holding cores used in experiments; a gas supply device 2 and a liquid supply device 3, both connected to the input end of the core holder 1, for supplying a mixed fluid into the core holder 1; a temperature control device 4 for controlling the temperature of the fluids supplied by the gas supply device 2 and the liquid supply device 3. In this embodiment, the temperature control device 4 is located at the inlet of the core holder 1, meaning that the gas and liquid supplied by the gas supply device 2 and the liquid supply device 3 are first heated by the temperature control device 4 before entering the core holder 1, for heating the mixed fluid supplied by the gas supply device 2 and the liquid supply device 3. The specific structure of the temperature control device 4 is conventional technology in the art and will not be described in detail here; and an axial pressure loading device 5 connected to the core holder 1 for applying pressure to the core holder 1. Axial pressure is applied to the core within the core holder 1; a confining pressure loading device 6, connected to the core holder 1, is used to apply confining pressure to the core within the core holder 1; a gas-liquid-solid separation device, connected to the output end of the core holder 1, is used to perform solid-liquid-gas analysis on the sand products discharged from the core holder 1. In this embodiment, specifically, the gas-liquid-solid separation device includes a solid-liquid separation device 8, a gas-liquid separation device 9, and a sand collection device 10. The solid-liquid separation... The input end of device 8 is connected to the output end of the core holder 1. The sand collecting device 10 is connected to the solid output port of the solid-liquid separation device 8. The input end of the gas-liquid separation device 9 is connected to the liquid output port of the solid-liquid separation device 8. A wet flow meter 11 is provided at the gas output port of the gas-liquid separation device 9. A sand discharge monitoring device 7 is installed between the core holder 1 and the gas-liquid-solid separation device to monitor the critical point and critical time of sand discharge from the core. The sand collecting device 10 is used to separate sand in the mixed fluid and can measure the sand discharge in real time, thereby recording the total time used by the sand discharge device to discharge discrete sand, and determining the sand discharge rate based on the total mass and total time. The gas-liquid separation device is connected after the solid-liquid separation device to separate gas and liquid in the mixed fluid. The gas flow rate is measured by the wet flow meter 11, and the core permeability can be determined based on the inlet and outlet flow rates of the sand discharge device.

[0043] In actual operation, a core of a certain specification is placed in the core holder 1. The core holder 1 is connected to the axial pressure loading device 5 and the confining pressure loading device 6 through pipelines. The axial pressure loading device 5 can apply a certain axial pressure to the core in the core holder 1, and the confining pressure loading device 6 can apply a certain confining pressure to the core in the core holder 1. The gas supply device 2 and the liquid supply device 3 can provide the core with a certain flow rate, pressure and a certain gas-liquid ratio of mixed fluid. At the same time, after the temperature reaches the temperature required for the experiment through the temperature control device 4, the experimental core in the core holder 1 enters the core. After the mixed gas passes through the sand discharge device, it carries a certain amount of discrete sand and enters the solid-liquid separation device through the pipeline. At the same time, the sand discharge monitoring device 7 between the outlet of the core holder 1 and the solid-liquid separation device monitors the critical point and critical time of sand discharge from the core. After the mixed gas passes through the solid-liquid separation device, the discrete sand is separated and enters the sand collection device 10. During the experiment, the total time taken for the discrete sand to be discharged by the sand discharge device is recorded, and the sand discharge rate of the core is determined based on the total mass of discrete sand and the total sand discharge time. After the sand-free mixed gas passes through the gas-liquid separation device, the liquid is separated, and the gas flow rate is measured by the wet flow meter 11, which can further determine the permeability of the experimental core.

[0044] like Figure 2As shown, specifically in this embodiment, the core clamp 1 includes a cylindrical body 1-1. The inner cavity of the cylindrical body 1-1 is cylindrical. Internal threads are provided on the inner walls of both ends of the cylindrical body 1-1. A left pressure cap 1-2 and a right pressure cap 1-3 are respectively provided inside both ends of the cylindrical body 1-1. Both the left pressure cap 1-2 and the right pressure cap 1-3 are threadedly connected to the inner walls of the cylindrical body 1-1. The ends of the left pressure cap 1-2 and the right pressure cap 1-3 are located away from each other. The outer diameter is larger than the inner diameter of the cylinder 1-1, thereby achieving the limiting installation of the left pressure cap 1-2 and the right pressure cap 1-3. Tapered sleeves 1-4 are fixedly provided on the opposite ends of the left pressure cap 1-2 and the right pressure cap 1-3. The two tapered sleeves 1-4 are respectively fixedly connected to the left pressure cap 1-2 and the right pressure cap 1-3 by screws to prevent relative movement of the tapered sleeves 1-4 within the cylinder 1-1. Adhesive is provided between the two tapered sleeves 1-4. Sleeve 1-5, the two ends of which are respectively pressed and fixed to the inner wall of cylinder 1-1 by two tapered sleeves 1-4. A confining cavity 1-6 is formed between the middle of the sleeve 1-5 and the inner wall of cylinder 1-1. Specifically, the sleeve 1-5 has a cylindrical structure, and the outer diameter of the two ends of the sleeve 1-5 is larger than the outer diameter of the middle, thereby forming a concave annular groove structure in the middle of the sleeve 1-5. After the rubber sleeve 1-5 is installed, the outer wall of the middle part of the rubber sleeve 1-5 and the inner wall of the cylinder 1-1 form the confining pressure cavity 1-6. The cylinder 1-1 is provided with a confining pressure port 1-7 that communicates with the confining pressure cavity 1-6. The confining pressure port 1-7 is connected to the confining pressure loading device 6. Since the rubber sleeve 1-5 has a certain elasticity, after the confining pressure loading device 6 applies pressure, the middle part of the rubber sleeve 1-5 is recessed inward, applying confining pressure to the rock core located in the rubber sleeve 1-5.

[0045] Furthermore, a small pressure cap 1-8 is fixedly provided on the inner side of the left pressure cap 1-2. A shaft pressure cylinder 1-9 is sealed and fixedly connected to one end of the cylinder 1-1 where the right pressure cap 1-3 is located. A cap 1-10 is integrally fixed to one end of the shaft pressure cylinder 1-9 away from the cylinder 1-1. A steering piston 2-61-11 is slidably provided on the inner side of the shaft pressure cylinder 1-9. One end of the steering piston 2-61-11 passes through and extends out of the cap 1-10 and is slidably and sealingly connected to the cap 1-10. A shaft pressure port 1-12 communicating with the inside of the shaft pressure cylinder 1-9 is provided near the cap 1-10. The output end of the shaft pressure loading device 5 is connected to the shaft pressure port 1-12 for injecting fluid into the shaft pressure cylinder 1-9, driving the steering piston 2-61-11 to move along the axial direction of the shaft pressure cylinder 1-9. The small pressure cap 1-8 and the steering piston 1-8... -11 Core plugs 1-13 are provided on opposite sides of each other. A core chamber 1-14 is formed between the two core plugs 1-13, which is the same as the core chamber. In this embodiment, a cylindrical pad 1-22 is provided between the small pressure cap 1-8 and the core plug 1-13. The peripheral wall of the pad 1-22 is detachably connected to the inner wall of the left pressure cap 1-2 by threads. One end of the pad 1-22 abuts against the small pressure cap 1-8, and the other end abuts against the core plug 1-13. One core plug 1-13 is provided with an inlet channel 1-15 that passes through both ends of the core plug 1-13. The other core plug 1-13 is provided with an outlet channel 1-16 that passes through both ends of the core plug 1-13. The inlet channel 1-15 is connected to the gas supply device 2 and the liquid supply device 3. The outlet channel 1-16 is connected to the gas-liquid-solid separation device. The core is placed in the core chamber 1-14, and pressure is applied to the confining pressure chamber 1-6 by the confining pressure loading device 6, thereby achieving confining pressure loading on the core. Pressure is applied to the axial pressure cylinder 1-9 by the axial pressure loading device 5, which drives the steering piston 2-61-11 to move, thereby driving the core plug 1-13 connected to the steering piston 2-61-11 to move, applying a certain axial pressure to the core. The gas supply device 2 and the liquid supply device 3 provide the core with a mixed fluid with a certain flow rate, pressure and a certain gas-liquid ratio. After passing through the core, the mixed fluid carries a certain amount of discrete sand into the solid-liquid separation device, which is used to simulate the effects of different production pressure differentials, different gas volumes and different liquid volumes on formation sand production.

[0046] In this embodiment, the inlet channel 1-15 is connected to one end of the first inlet pipe 12, and the other end of the first inlet pipe 12 is connected to the output port of the first valve 13. The input port of the first valve 13 is connected to the output ports of the gas supply device 2 and the liquid supply device 3 through the second inlet pipe 14. The outlet channel 1-16 is connected to one end of the first outlet pipe 15, and the other end of the first outlet pipe 15 is connected to the input port of the second valve 16. The output port of the second valve 16 is connected to one end of the second outlet pipe 17, and the other end of the second outlet pipe 17 is connected to the input port of the gas-liquid-solid separation device. The two ports of the third valve 18 are respectively connected to the second inlet pipe 14 and the first outlet pipe 15 through pipes. The two ports of the fourth valve 19 are respectively connected to the first inlet pipe 12 and the second outlet pipe 17 through pipes. By adjusting the first valve 13, the second valve 16, and the third valve... The opening and closing of valve 18 and the fourth valve 19 realize the forward and reverse driving of the fluid. When the first valve 13 and the second valve 16 are opened and the third valve 18 and the fourth valve 19 are closed, the fluid input from the second inlet pipe 14 passes through the first valve 13, the first inlet pipe 12, the core cavity, the first outlet pipe 15, the second valve 16, and the second outlet pipe 17 in sequence before entering the gas-liquid-solid separation device. When the third valve 18 and the fourth valve 19 are opened and the first valve 13 and the second valve 16 are closed, the fluid input from the second inlet pipe 14 passes through the third valve 18, the first outlet pipe 15, the core cavity, the first inlet pipe 12, the fourth valve 19, and the second outlet pipe 17 in sequence before entering the gas-liquid-solid separation device. By controlling the opening of the first valve 13, the second valve 16, the third valve 18, and the fourth valve 19, the forward and reverse driving of the fluid is realized, thereby realizing the simulation of gas injection and gas extraction in a gas storage facility.

[0047] Based on the above embodiments, the following improvements can be made to this embodiment: an annular seat 1-17 is integrally fixed on the outer wall of the steering piston 1-11, the outer wall of the annular seat 1-17 is slidably connected to the inner wall of the axial pressure cylinder 1-9, the axial pressure port 1-12 is located between the cover 1-10 and the annular seat 1-17, an annular groove 1-18 is provided on the peripheral wall of the annular seat 1-17, and a sealing ring assembly 1-19 is provided in the annular groove 1-18, the sealing ring assembly including a PTFE retaining ring and an O-ring. The annular seat 1-17 protruding from the outer wall of the steering piston 1-11 and the inner wall of the axial pressure cylinder 1-9 form a sealed sliding contact, thereby forming a sealed chamber between the outer wall of the steering piston 1-11, the inner wall of the axial pressure cylinder 1-9, the annular seat 1-17 and the cover 1-10. The axial pressure loading device 5 injects gas or liquid to pressurize and push the annular seat 1-17 to move, thereby driving the steering piston 1-11 to move and realize axial pressure on the rock core. By setting the annular groove 1-18 and setting the sealing ring assembly 1-19 in the annular groove 1-18, the sealing performance and service life between the peripheral wall of the annular seat 1-17 and the inner wall of the axial pressure cylinder 1-9 are ensured.

[0048] like Figure 3 As shown, in this embodiment, the two core plugs 1-13 have a star-shaped groove 1-20 and / or multiple annular grooves 1-21 facing each other. The star-shaped groove 1-20 and / or multiple annular grooves 1-21 can increase the contact area between the mixed fluid and the core cross-section. In this embodiment, the end face of the core plug 1-13 is provided with a star-shaped groove 1-20 and multiple concentric annular grooves 1-21. The inner diameter of the inlet channel 1-15 and the outlet channel 1-16 on the core plug 1-13 is 2mm. The width of the star-shaped groove 1-20 and the annular groove 1-21 is 1.5mm and the depth is 0.5mm, thereby increasing the contact area between the mixed fluid and the core end face.

[0049] like Figure 4As shown, preferably, the gas supply device 2 includes a gas compressor 2-1, a piston container 2-2, a displacement sensor 2-7, and a constant speed and pressure pump 2-3. The first end of the piston container 2-2 is connected to a multi-way valve 2-4. The output end of the gas compressor 2-1 is connected to one port of the multi-way valve 2-4 via a pipe. The second end of the piston container 2-2 is connected to the output end of the constant speed and pressure pump 2-3 via a pipe. The input end of the constant speed and pressure pump 2-3 is connected to a water tank 2-5 via a pipe. A piston 2-6 is located in the middle of the piston container 2-2. The other port of the multi-way valve 2-4 is connected to the input end of the core clamp 1 via a pipe. The piston 2-6 is connected to... Displacement sensor 2-7 is used to detect the displacement of piston 2-6 within piston container 2-2. Gas compressor 2-1 supplies compressed gas through a pipeline into piston container 2-2, causing piston 2-6 to move within the container and storing a certain amount of compressed gas. Then, the port connecting multi-way valve 2-4 to gas compressor 2-1 is closed, and the port connecting multi-way valve 2-4 to core holder 1 is opened. Liquid is injected into piston container 2-2 via constant speed and constant pressure pump 2-3, pushing piston 2-6 to move and thus allowing gas to be injected into core holder 1 at a constant flow rate. The displacement sensor 2-7 can accurately measure the movement distance of piston 2-6 in real time, further ensuring the constant flow rate of gas injection. In this embodiment, a constant speed pump can be used as the liquid supply device 3.

[0050] like Figure 5As shown, further, the piston container 2-2 includes a piston cylinder 2-8, and the piston 2-6 is disposed inside the piston cylinder 2-8. The peripheral wall of the piston 2-6 is slidably connected to the inner wall of the piston cylinder 2-8. Piston plugs 2-9 are provided at both ends inside the piston cylinder 2-8. Piston caps 2-10 are fixedly provided at both ends of the piston cylinder 2-8 to restrict the piston plugs 2-9 inside the piston cylinder 2-8. One end of each of the two piston plugs 2-9 passes through and extends out of the two piston caps 2-10. The piston plugs 2-9 are provided with flow channels 2-11 that penetrate both ends of the piston plugs 2-9. The two flow channels 2-11 are respectively connected to one port of the multi-way valve 2-4 and the output end of the constant speed and constant pressure pump 2-3. The piston plugs 2-9 are sealed inside both ends of the piston cylinder 2-8 by the caps, which facilitates the placement of the piston 2-6 inside the piston cylinder 2-8 and facilitates the assembly of the entire piston container 2-2. In this embodiment, to prevent the piston 2-6 from being tightly pressed together with the piston plug 2-9 after they come into contact, thus preventing the injection of liquid for pressurization, both piston plugs 2-9 have concave surfaces 2-13 on their opposite sides. This ensures that even when the piston 2-6 and piston plug 2-9 come into contact, there is still a gap between their middle parts. This gap facilitates the injection of liquid to pressurize the piston 2-6. Furthermore, an annular groove 2-12 is provided on the outer peripheral wall of piston 2-6. The end face of piston 2-6 facing the constant speed and constant pressure pump 2-3 has a hole communicating with the annular groove 2-12. When the constant speed and constant pressure pump 2-3 adds liquid, some liquid enters into the annular groove 2-12, reducing the friction between the outer peripheral wall of piston 2-6 and piston cylinder 2-8, and facilitating the smooth movement of piston 2-6. Sealing ring assemblies 1-19 are provided on the outer peripheral walls of piston 2-6 on both sides of the annular groove 2-12 to improve the sealing between piston 2-6 and the inner wall of piston cylinder 2-8.

[0051] This invention can simulate reservoir sand production under different downhole gas injection and production volumes and liquid volumes; it can simulate the impact of alternating injection and production conditions in gas storage facilities on formation sand production; it can simulate the impact of different production pressure differentials and different gas volumes on formation sand production; and it can accurately record the critical point of sand production, sand production volume, and sand production rate.

[0052] In the description of this invention, it should be understood that the terms "center," "length," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "inner," "outer," "circumferential," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the system or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0053] In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0054] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0055] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A simulation experimental device for reservoir sand production under injection and production conditions in an oil and gas reservoir, characterized in that, include Core holder (1), the core holder (1) is used to hold the core for the experiment; Gas supply device (2) and liquid supply device (3), both of which are connected to the input end of the core holder (1) and are used to supply mixed fluid into the core holder (1); Temperature control device (4), the temperature control device (4) is used to control the temperature of the fluids supplied by the gas supply device (2) and the liquid supply device (3); Axial pressure loading device (5), which is connected to the core holder (1), is used to apply axial pressure to the core in the core holder (1); A confining pressure loading device (6) is connected to the core holder (1) and is used to apply confining pressure to the core inside the core holder (1). A gas-liquid-solid separation device is connected to the output end of the core holder (1) and is used to perform solid-liquid-gas analysis on the sand discharge product discharged from the core holder (1). Sand discharge monitoring device (7), the sand discharge monitoring device (7) is located between the core holder (1) and the gas-liquid-solid separation device, and is used to monitor the critical point and critical time of sand discharge from the core; The core holder (1) includes a cylindrical body (1-1). The inner walls of both ends of the cylindrical body (1-1) are provided with internal threads. The inner walls of both ends of the cylindrical body (1-1) are respectively provided with a left pressure cap (1-2) and a right pressure cap (1-3). The left pressure cap (1-2) and the right pressure cap (1-3) are both connected to the inner wall of the cylindrical body (1-1) by threads. A small pressure cap (1-8) is fixedly provided on the inner side of the left pressure cap (1-2). The end of the cylinder (1-1) with the right pressure cap (1-3) is sealed and fixedly connected to the axial pressure cylinder (1-9). The end of the axial pressure cylinder (1-9) away from the cylinder (1-1) is integrally fixedly provided with a cover (1-10). A steering piston (1-11) is slidably provided on the inner side of the axial pressure cylinder (1-9). One end of the steering piston (1-11) passes through and extends out of the cover (1-10) and is slidably sealed to the cover (1-10). The axial pressure cylinder (1-9) near the cover (1-10) is provided with an axial pressure port (1-12) communicating with the inside of the axial pressure cylinder (1-9). The output end of the axial pressure loading device (5) is connected to the axial pressure port (1-12) for feeding the axial pressure cylinder (1-9). The injected fluid drives the steering piston (1-11) to move along the axial direction of the axial pressure cylinder (1-9); the small pressure cap (1-8) and the steering piston (1-11) are provided with core plugs (1-13) on opposite sides, and the two core plugs (1-13) form a core chamber (1-14) for placing the core; one core plug (1-13) is provided with an inlet channel (1-15) penetrating both ends of the core plug (1-13), and the other core plug (1-13) is provided with an outlet channel (1-16) penetrating both ends of the core plug (1-13). The inlet channel (1-15) is connected to the gas supply device (2) and the liquid supply device (3), and the outlet channel (1-16) is connected to the gas-liquid-solid separation device; An annular seat (1-17) is integrally fixed on the outer wall of the steering piston (1-11). The outer wall of the annular seat (1-17) is slidably connected to the inner wall of the axial pressure cylinder (1-9). The axial pressure port (1-12) is located between the cover (1-10) and the annular seat (1-17).

2. The reservoir sand production simulation experimental device under injection and production conditions of an oil and gas reservoir-type gas storage facility according to claim 1, characterized in that, Tapered sleeves (1-4) are fixedly provided on the opposite ends of the left pressure cap (1-2) and the right pressure cap (1-3). A rubber sleeve (1-5) is provided between the two tapered sleeves (1-4). The two ends of the rubber sleeve (1-5) are respectively pressed and fixed on the inner wall of the cylinder (1-1) by the two tapered sleeves (1-4). A confining pressure cavity (1-6) is formed between the middle part of the rubber sleeve (1-5) and the inner wall of the cylinder (1-1) at intervals. A confining pressure port (1-7) communicating with the confining pressure cavity (1-6) is provided on the cylinder (1-1). The confining pressure port (1-7) is communicating with the confining pressure loading device (6).

3. The reservoir sand production simulation experimental device under injection and production conditions of an oil and gas reservoir-type gas storage facility according to claim 2, characterized in that, The inlet channel (1-15) is connected to one end of the first inlet pipe (12), and the other end of the first inlet pipe (12) is connected to the output port of the first valve (13). The input port of the first valve (13) is connected to the output ports of the gas supply device (2) and the liquid supply device (3) through the second inlet pipe (14). The outlet channel (1-16) is connected to one end of the first outlet pipe (15), and the other end of the first outlet pipe (15) is connected to the input port of the second valve (16). The output port of the second valve (16) is connected to one end of the second outlet pipe (17), and the other end of the second outlet pipe (17) is connected to the input port of the gas-liquid-solid separation device. The two ports of the third valve (18) are connected to the second inlet pipe (14) and the first outlet pipe (15) through pipes, respectively. The two ports of the fourth valve (19) are connected to the first inlet pipe (12) and the second outlet pipe (17) through pipes, respectively.

4. The reservoir sand production simulation experimental device under injection and production conditions of an oil and gas reservoir-type gas storage facility according to claim 1, characterized in that, The annular seat (1-17) has an annular groove (1-18) on its peripheral wall, and a sealing ring assembly (1-19) is provided in the annular groove (1-18).

5. The reservoir sand production simulation experimental device under injection and production conditions of an oil and gas reservoir-type gas storage facility according to claim 2, characterized in that, The two core plugs (1-13) have a star-shaped groove (1-20) and / or multiple annular grooves (1-21) on their opposite sides.

6. The reservoir sand production simulation experimental device under injection and production conditions of an oil and gas reservoir-type gas storage facility according to any one of claims 1 to 5, characterized in that, The gas supply device (2) includes a gas compressor (2-1), a piston container (2-2), and a constant speed and constant pressure pump (2-3). The first end of the piston container (2-2) is connected to a multi-way valve (2-4). The output end of the gas compressor (2-1) is connected to one port of the multi-way valve (2-4) through a pipe. The second end of the piston container (2-2) is connected to the output end of the constant speed and constant pressure pump (2-3) through a pipe. The input end of the constant speed and constant pressure pump (2-3) is connected to a water tank (2-5) through a pipe. A piston (2-6) is provided in the middle of the piston container (2-2). The other port of the multi-way valve (2-4) is connected to the input end of the core holder (1) through a pipe.

7. The reservoir sand production simulation experimental device under injection and production conditions of an oil and gas reservoir-type gas storage facility according to claim 6, characterized in that, The piston (2-6) is connected to a displacement sensor (2-7) for detecting the displacement of the piston (2-6) within the piston container (2-2).

8. The reservoir sand production simulation experimental device under injection and production conditions of an oil and gas reservoir-type gas storage facility according to claim 6, characterized in that, The piston container (2-2) includes a piston cylinder (2-8), and a piston (2-6) is disposed inside the piston cylinder (2-8). The peripheral wall of the piston (2-6) is slidably connected to the inner wall of the piston cylinder (2-8). Piston plugs (2-9) are provided at both ends inside the piston cylinder (2-8). Piston caps (2-10) for confining the piston plugs (2-9) inside the piston cylinder (2-8) are fixedly provided at both ends of the piston cylinder (2-8). One end of each of the two piston plugs (2-9) passes through and extends out of the two piston caps (2-10). A flow channel (2-11) is provided on the piston plug (2-9) through both ends of the piston plug (2-9). The two flow channels (2-11) are respectively connected to one port of the multi-way valve (2-4) and the output end of the constant speed and constant pressure pump (2-3).

9. A reservoir sand production simulation experimental device under injection and production conditions in an oil and gas reservoir type gas storage facility according to any one of claims 1 to 5, characterized in that, The gas-liquid-solid separation equipment includes a solid-liquid separation device (8), a gas-liquid separation device (9), and a sand collection device (10). The input end of the solid-liquid separation device (8) is connected to the output end of the core holder (1). The sand collection device (10) is connected to the solid output port of the solid-liquid separation device (8). The input end of the gas-liquid separation device (9) is connected to the liquid output port of the solid-liquid separation device (8). A wet flow meter (11) is provided at the gas output port of the gas-liquid separation device (9).

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