Sand production simulation experiment device for gas storage of exhausted gas reservoir

Abstract

The utility model discloses a sand production simulation experiment device for a gas storage of an exhausted gas reservoir, which relates to the technical field of oil-gas exploration and comprises a high-pressure reaction kettle, a rock core holder is arranged in the high-pressure reaction kettle, a rock core is clamped in the rock core holder, and the high-pressure reaction kettle comprises a kettle bottom and a kettle cover which are buckled in a sealing manner. A pressing rod is mounted at the top of the kettle cover corresponding to the upper part of the rock core holder in a sealing and sliding manner; an axial pressure driving device is connected to the pressing rod; the high-pressure reaction kettle is also connected with a confining pressure loading pump set; the rock core holder is connected with a gas supply system and a liquid supply system; a fluid outlet corresponding to the circular groove is formed in the sand outlet unit lower seat, a sand outlet pipe is connected to the fluid outlet, and the sand outlet pipe penetrates out of the kettle bottom and is connected with a sand outlet detection system and a sand collecting system. The high-pressure reaction kettle is arranged, the confining pressure is changed, and mixed fluid with different gas-liquid ratios is introduced, so that more accurate simulation data is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of oil and gas exploration, in particular to a sand production simulation experiment device for a depleted gas reservoir gas storage. Background Art

[0002] Under cyclic alternating loads, the reservoir rock of a depleted gas reservoir gas storage is damaged, and when the damage amount accumulates to a certain extent with the action of the alternating load, sand production will occur in the injection-production wells. The sand production from the reservoir includes loose free sand and sand produced by the fragmentation of the reservoir skeleton. According to the rock mechanics theory, the damage and fragmentation of the reservoir skeleton near the wellbore are the fundamental reasons for sand production.

[0003] However, the existing simulation experiment equipment cannot intuitively simulate the actual working conditions of the injection-production wells of the gas storage, so the measured values are not accurate. Content of the Utility Model

[0004] The purpose of the utility model is to provide a sand production simulation experiment device for a depleted gas reservoir gas storage. By setting a high-pressure reactor and changing the confining pressure and introducing a mixed fluid with different gas-liquid ratios, more accurate simulation data can be achieved.

[0005] To achieve the above purpose, the utility model provides a sand production simulation experiment device for a depleted gas reservoir gas storage, which includes a base. A high-pressure reactor is arranged on the base. A core holder is arranged inside the high-pressure reactor. A core is clamped inside the core holder. The core is of a cylindrical structure, and a circular groove is opened at the center position of its bottom. The high-pressure reactor includes a reactor bottom and a reactor cover that are hermetically buckled. A pressure rod is hermetically and slidably installed above the core holder corresponding to the top of the reactor cover. An axial pressure driving device is connected to the pressure rod. The axial pressure driving device controls the pressure rod to press down and tightly press on the core holder. An inlet and an outlet are also arranged on the high-pressure reactor. The inlet and the outlet are connected to a confining pressure loading pump group. The core holder includes an upper sand production unit seat and a lower sand production unit seat that are arranged opposite to each other up and down. The upper sand production unit seat and the lower sand production unit seat are hermetically connected by a rubber sleeve. The upper sand production unit seat, the lower sand production unit seat and the rubber sleeve enclose a core clamping cavity, and the core is clamped inside the core clamping cavity. A high-permeability layer is clamped between the core and the upper sand production unit seat. The core is in sealed contact with the lower sand production unit seat. A fluid inlet is opened on the upper sand production unit seat. The fluid inlet is connected to a gas supply system and a liquid supply system. A fluid outlet corresponding to the circular groove is arranged on the lower sand production unit seat. A sand production pipe is connected to the fluid outlet. The sand production pipe passes through the reactor bottom and is connected to a sand production detection system and a sand collection system.

[0006] After adopting the above structure, a circular groove is opened at the center of the bottom of the core, the core is clamped in the core clamp, the core clamp is placed in the high-pressure reactor, the bottom and cover of the high-pressure reactor are sealed and buckled, the axial pressure driving device controls the pressure rod to press down and press on the core clamp, and the axial pressure is applied to the core; the confining pressure loading pump group applies confining pressure to the core; then the mixed fluid provided by the gas supply system and the liquid supply system is injected into the core clamp, the mixed fluid enters the core clamp, and the mixed fluid with different gas-liquid ratios is applied to the core, the fluid pressure generates a pressure difference in the central circular groove to simulate the real production pressure difference, and at the same time, the critical point and critical time of sand production of the core are monitored through the sand production detection system and the sand collection system, and the sand production amount and volume are observed, so as to simulate the influence of different production pressure differences, different gas volumes, and different liquid volume parameters on formation sand production, and the experimental data are more intuitive and accurate.

[0007] In order to more conveniently buckle the kettle cover on the kettle bottom and realize the sealing of the high-pressure reactor, the kettle cover is slidably mounted on the base, and a buckling driving device is arranged on the base to drive the kettle cover to buckle on the kettle bottom.

[0008] In order to reduce the investment in the drive device and reduce the cost of the device, the snap-on drive device is shared with the axial pressure drive device, that is, the axial pressure drive device is fixed on the base and located above the high-pressure reactor, and a stopper sleeve is provided on the output shaft of the axial pressure drive device above the reactor cover, and a compression spring is clamped between the stopper sleeve and the reactor cover.

[0009] In order to ensure the sealing between the lower seat of the sand production unit and the rock core, a sealing gasket is clamped between the lower seat of the sand production unit and the rock core.

[0010] In order to realize the rapid positioning of the core holder, a positioning groove is provided on the bottom of the kettle, and the core holder is placed in the positioning groove.

[0011] In order to ensure the sealing of the core clamping cavity, sealing tapes are provided between the rubber sleeve and the upper seat of the sand production unit, and between the rubber sleeve and the lower seat of the sand production unit.

[0012] In order to prevent the output shaft of the axial pressure driving device from slipping out of the through hole; and at the same time, to avoid pressure concentration and uneven axial pressure when the axial pressure driving device applies axial pressure to the core clamp, a pressure plate is fixed at the bottom of the output shaft of the axial pressure driving device, and the diameter of the pressure plate is larger than the diameter of the sliding hole.

[0013] In order to ensure better guidance of the output shaft of the shaft pressure drive device, a guide ring is fixed on the top of the kettle cover, and the pressure rod passes through the guide ring.

[0014] In order to ensure the stability of fluid pressure, the fluid inlet is set at the center of the upper seat of the sand discharge unit.

[0015] After adopting the above technical solution, the beneficial effects of the present utility model are as follows:

[0016] The sand production simulation experiment device for a depleted gas reservoir gas storage of the present utility model solves the technical problem that the detection data of the existing sand production simulation experiment device in the prior art is inaccurate. By setting a high-pressure reactor and changing the confining pressure and introducing a mixed fluid with different gas-liquid ratios, the present utility model can achieve more accurate simulation data. Brief Description of the Drawings

[0017] Figure 1 is a connection schematic diagram of a sand production simulation experiment device for a depleted gas reservoir gas storage of the present utility model;

[0018] Figure 2 is a structural schematic diagram of a sand production simulation experiment device for a depleted gas reservoir gas storage of the present utility model;

[0019] Figure 3 is a structural schematic diagram of the axial pressure driving device, the retaining sleeve and the compression spring in Embodiment 2;

[0020] Figure 4 is a structural schematic diagram of the core holder.

[0021] In the figures, 1 is the base, 11 is the guide post, 12 is the support plate, 2 is the high-pressure reactor, 201 is the inlet, 202 is the outlet, 21 is the bottom of the kettle, 22 is the kettle cover, 221 is the guide ring, 23 is the pressure rod, 24 is the axial pressure driving device, 241 is the retaining sleeve, 25 is the compression spring, 3 is the core holder, 31 is the upper seat of the sand production unit, 311 is the fluid inlet, 32 is the lower seat of the sand production unit, 321 is the fluid outlet, 33 is the rubber sleeve, 34 is the high-permeability layer, 36 is the sealing gasket, 4 is the confining pressure loading pump group, 5 is the core, 51 is the circular groove, 6 is the gas supply system, and 7 is the liquid supply system. Detailed Embodiments

[0022] The present utility model will be further described below with reference to the drawings.

[0023] All orientations mentioned in this specification are based on the orientation when the sand production simulation experiment device for a depleted gas reservoir gas storage of the present utility model is working properly, without limiting its orientation during storage and transportation, only representing the relative positional relationship, not the absolute positional relationship.

[0024] Embodiment 1:

[0025] As Figure 1 、 Figure 2 and Figure 3As shown together, a depleted gas reservoir gas storage sand production simulation experimental device comprises a base 1, a high pressure reactor 2 is arranged on the base 1, a core holder 3 is arranged in the high pressure reactor 2, a positioning groove is arranged at the bottom of the high pressure reactor 2, and the core holder 3 is placed in the positioning groove, so as to realize the rapid positioning of the core holder 3. The core holder 3 holds the experimental core 5.

[0026] Preparation of core 5: The core taken out from the coring well of the gas storage reservoir is prepared into a cylindrical core 5 of 100×50 mm, and a circular groove 51 of two-thirds of the core length is drilled at the center of the lower end surface of the cylindrical core 5, with an inner and outer diameter ratio of 1:3.

[0027] The high-pressure reactor 2 includes a sealed bottom 21 and a lid 22. A through hole is provided on the top of the lid 22 corresponding to the top of the core holder 3. The through hole penetrates the lid 22. A pressure rod 23 is slidably installed in the through hole. A sealing sleeve is provided between the pressure rod 23 and the through hole, so as to ensure that when the pressure rod 23 slides up and down, the position of the through hole remains sealed to avoid leakage. An axial pressure driving device 24 is connected to the pressure rod 23. In this embodiment, the axial pressure driving device 24 is a hydraulic cylinder. In actual applications, an electric cylinder or an electric push rod can also be used to fix the axial pressure driving device 24 on the top of the lid 22. The output shaft of the axial pressure driving device 24 is extended and retracted to drive the pressure rod 23 to press down and press on the core holder 3, so as to apply a certain axial pressure to the core holder 3.

[0028] Furthermore, a pressure plate is fixed at the bottom of the output shaft of the axial pressure driving device 24, and the diameter of the pressure plate is larger than the diameter of the sliding hole. By setting the pressure plate, when the axial pressure driving device 24 does not apply axial pressure to the core clamp 3, the pressure plate prevents the output shaft of the axial pressure driving device 24 from slipping out of the through hole; at the same time, when the axial pressure driving device 24 applies axial pressure to the core clamp 3, the pressure plate increases the contact area with the core clamp 3, avoiding pressure concentration and causing uneven axial pressure.

[0029] In order to ensure that the output shaft of the axial pressure driving device 24 has stronger guiding performance when it is extended and retracted, a guide ring 221 is provided on the top of the kettle cover 22. The guide ring 221 is fixed to the top of the kettle cover 22 through a fixing frame, and the axis of the guide ring 221 is coaxial with the through hole on the top of the kettle cover 22. The output shaft of the axial pressure driving device 24 passes through the guide ring 221 and the through hole in sequence and then penetrates into the bottom of the kettle cover 22.

[0030] The high-pressure reactor 2 is also provided with an inlet 201 and an outlet 202. A confining pressure loading pump set 4 is connected between the inlet 201 and the outlet 202; the confining pressure loading pump set 4 is used to apply confining pressure to the core 5 in the core holder 3. The confining pressure loading pump set 4 injects a liquid or gas of a certain pressure into the high-pressure reactor 2, thereby applying a certain confining pressure to the core holder 3. The confining pressure loading pump set 4 belongs to the prior art, and this embodiment will not be described in detail.

[0031] As shown Figure 4 in the figure, the core holder 3 includes a sand outlet unit upper seat 31 and a sand outlet unit lower seat 32 which are arranged opposite to each other up and down. The sand outlet unit upper seat 31 and the sand outlet unit lower seat 32 are hermetically connected through a rubber sleeve 33. In order to ensure the sealing performance, sealing tapes are provided between the rubber sleeve 33 and the sand outlet unit upper seat 31, and between the rubber sleeve 33 and the sand outlet unit lower seat 32. The sand outlet unit upper seat 31, the sand outlet unit lower seat 32 and the rubber sleeve 33 enclose a closed core holding cavity, and the core 5 is held in the core holding cavity. Since the sand outlet unit upper seat 31 and the sand outlet unit lower seat 32 are connected through a flexible rubber sleeve 33, when axial pressure and confining pressure are applied to the core holder 3, the axial pressure and confining pressure are completely applied to the core 5.

[0032] A high-permeability layer 34 is clamped between the core 5 and the sand outlet unit upper seat 31; the core 5 is in sealed contact with the sand outlet unit lower seat 32. In order to ensure the sealing effect, a sealing gasket 36 is clamped between the core 5 and the sand outlet unit lower seat 32. A fluid inlet 311 is provided on the sand outlet unit upper seat 31. In order to ensure the stability of the mixed fluid pressure application, the fluid inlet 311 is arranged at the center position of the sand outlet unit upper seat 31. The fluid inlet 311 is connected to the gas supply system 6 and the liquid supply system 7; the gas supply system 6 and the liquid supply system 7 are used to provide mixed fluid into the core holder 3. In order to avoid the connection pipe affecting the sealing performance of the high-pressure reactor 2, a connector is provided on the bottom 21 of the kettle in this embodiment. The connector passes through the side of the bottom 21 of the kettle to connect the gas supply system 6 and the liquid supply system 7, and the connector penetrates into the kettle from above the bottom 21 and is connected to the fluid inlet 311 through a quick connector and a connecting pipe.

[0033] A fluid outlet 321 is provided on the sand outlet unit lower seat 32 corresponding to the circular groove 51. A sand outlet pipe (not shown in the figure) is connected to the fluid outlet 321. A sand outlet detection system is provided on the sand outlet pipe. The sand outlet detection system is used to monitor the critical point of sand production and the critical time of sand production of the core 5. The sand outlet pipe is connected to a sand collection system. The sand collection system is used to collect and separate the mixed fluid and the sand and gravel. Since the sand detection system and the sand collection system belong to the prior art, and their principles and related functional structures can be referred to Chinese Patent CN115728444A, so they will not be elaborated here.

[0034] As shown Figure 1 , Figure 2 , Figure 3 and Figure 4 collectively shown, the operation steps of a sand production simulation experimental device for a depleted gas reservoir storage

[0035] First, install the core 5 on the core holder 3, then place the core holder 3 in the positioning groove of the high-pressure reactor 2, and then seal and fasten the kettle lid 22 in the kettle bottom 21. The telescopic movement of the output shaft of the axial pressure driving device 24 drives the pressure rod 23 to press down and tightly press on the core holder 3, applying a certain axial pressure to the core holder 3; the confining pressure loading pump group 4 injects a liquid or gas with a certain pressure into the high-pressure reactor 2, thereby applying a certain confining pressure to the core holder 3; the gas supply system 6 and the liquid supply system 7 inject a mixed fluid with a certain gas-liquid ratio into the fluid inlet 311. After the mixed fluid passes through the core 5, it carries a certain amount of discrete sand and enters the sand collection system through the sand outlet pipe. By changing the values of the gas supply system 6, the liquid supply system 7, and the confining pressure loading pump group 4, it is used to simulate the influence of different production pressure differences, different gas volumes, and different liquid volume parameters on formation sand production.

[0036] Embodiment 2:

[0037] As Figure 1 and Figure 2 collectively shown, this embodiment is further improved on the basis of Embodiment 1. In order to achieve automatic fastening, several guiding columns 11 are provided on the base 1 in this embodiment. Four guiding columns 11 are provided in this embodiment, and two guiding columns can be set according to needs in actual applications. The kettle lid 22 is fixedly installed on the support plate 12. Corresponding to the guiding columns 11 on the support plate 12, sliding holes are provided, and sliding sleeves are sleeved in the sliding holes, so as to realize the up-and-down sliding installation of the kettle lid 22 on the guiding columns 11.

[0038] The up-and-down sliding of the kettle lid 22 is controlled by a fastening driving device. By controlling the fastening driving device, the kettle lid 22 is hermetically fastened on the kettle bottom 21, realizing the sealing of the high-pressure reactor 2. The fastening driving device can adopt an independent driving device, such as a cylinder or an electric cylinder is provided on the base 1, and the kettle lid 22 is hermetically fastened on the kettle bottom 21 by the driving of the cylinder or the electric cylinder.

[0039] In this embodiment, in order to reduce the input of the driving device, the fastening driving device is shared with the axial pressure driving device 24. The specific connection method is as follows:

[0040] As Figure 3 shown, the axial pressure driving device 24 is fixed on the base 1 and is located above the high-pressure reactor 2. A retaining sleeve 241 is provided at a position above the kettle lid 22 on the output shaft of the axial pressure driving device 24. A compression spring 25 is clamped between the retaining sleeve 241 and the kettle lid 22.

[0041] When the output shaft of the axial pressure driving device 24 extends, it drives the high-pressure reactor 2 to move downward until it tightly presses on the kettle bottom 21. Continuing to press down the axial pressure driving device 24, the kettle bottom 21 restricts the continued movement of the kettle lid 22, the compression spring 25 is compressed, and the output shaft of the axial pressure driving device 24 drives the pressure rod 23 to continue to press down, realizing the application of the axial pressure.

[0042] Certainly, the above description is not a limitation to the present utility model, nor is the present utility model limited to the above examples. Changes, modifications, additions or substitutions made by those skilled in the art within the substantial scope of the present utility model shall also fall within the protection scope of the present utility model.

Claims

1. A sand production simulation experimental device for a depleted gas reservoir gas storage, characterized in that: It includes a base, on which a high-pressure reactor is provided. Inside the high-pressure reactor, a core holder is arranged, and a core is clamped inside the core holder. The core is of a cylindrical structure, and a circular groove is opened at the center position of its bottom; The high-pressure reactor includes a bottom and a lid that are hermetically fastened. Above the core holder and hermetically and slidably mounted on the top of the lid is a pressure rod, and an axial pressure driving device is connected to the pressure rod. The axial pressure driving device controls the pressure rod to press down and tightly press on the core holder; An inlet and an outlet are also provided on the high-pressure reactor, and the inlet and the outlet are connected to a confining pressure loading pump group; The core holder includes an upper seat of the sand discharging unit and a lower seat of the sand discharging unit that are arranged opposite to each other up and down. The upper seat of the sand discharging unit and the lower seat of the sand discharging unit are hermetically connected by a rubber sleeve. The upper seat of the sand discharging unit, the lower seat of the sand discharging unit and the rubber sleeve enclose a core clamping cavity, and the core is clamped in the core clamping cavity; A high-permeability layer is clamped between the core and the upper seat of the sand discharging unit; There is a sealed contact between the core and the lower seat of the sand discharging unit; A fluid inlet is opened on the upper seat of the sand discharging unit, and the fluid inlet is connected to a gas supply system and a liquid supply system; A fluid outlet is provided on the lower seat of the sand discharging unit corresponding to the circular groove, and a sand discharging pipe is connected to the fluid outlet. The sand discharging pipe passes through the bottom of the reactor and is connected to a sand discharging detection system and a sand collection system.

2. The sand production simulation experimental device for a depleted gas reservoir storage described in claim 1, wherein: The lid is slidably mounted up and down on the base, and a fastening driving device is provided on the base. The fastening driving device drives the lid to be fastened on the bottom.

3. The sand production simulation experimental device for a depleted gas reservoir gas storage described in claim 2, wherein: The fastening driving device is shared with the axial pressure driving device, that is, the axial pressure driving device is fixed on the base and located above the high-pressure reactor. A retaining sleeve is arranged on the output shaft of the axial pressure driving device above the lid, and a compression spring is clamped between the retaining sleeve and the lid.

4. A sand production simulation experimental device for a depleted gas reservoir gas storage reservoir according to claim 1, characterized in that: A sealing gasket is clamped between the lower seat of the sand discharging unit and the core.

5. The sand production simulation experimental device for a depleted gas reservoir gas storage described in claim 1, characterized in that: A positioning groove is provided on the bottom of the reactor, and the core holder is placed in the positioning groove.

6. The sand production simulation experimental device for a depleted gas reservoir gas storage described in claim 1, wherein: Sealing tapes are provided between the rubber sleeve and the upper seat of the sand discharging unit, and between the rubber sleeve and the lower seat of the sand discharging unit.

7. A sand production simulation experimental device for a depleted gas reservoir gas storage cavern according to claim 1, characterized in that: A pressing piece is fixed to the bottom of the output shaft of the axial pressure driving device, and the diameter of the pressing piece is larger than the diameter of the sliding hole.

8. A sand production simulation experimental device for a depleted gas reservoir gas storage, characterized in that: A guiding ring is fixed to the top of the lid, and the pressure rod passes through the guiding ring.

9. The sand production simulation experimental device for a depleted gas reservoir gas storage described in claim 1, wherein: The fluid inlet is arranged at the center position of the upper seat of the sand discharging unit.

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