Experimental device and method for high-temperature and high-pressure reservoir imbibition / gas reservoir competitive adsorption

Abstract

The invention discloses a high-temperature and high-pressure reservoir imbibition / gas reservoir competitive adsorption experimental device and method.The experimental device comprises an injection system, a metering analysis system and an experimental body located in a constant-temperature box, and the experimental body comprises an imbibition shell and a clamping barrel fixed in the imbibition shell; the bottom of the imbibition shell is provided with an opening communicated with a lower port of the clamping cylinder, a bottom plate is detachably arranged at the opening, the upper end and the lower end of the clamping cylinder are respectively matched with a partition top cover and a partition base in a sealing manner, and a rock core filling chamber is formed between the partition top cover and the partition base; a rotary push rod for pushing and pulling the partition base is arranged on the bottom plate, and a fastener for abutting against the top of the partition top cover is arranged on the imbibition shell; according to the scheme, an imbibition experiment and a gas reservoir competitive adsorption experiment in a high-temperature and high-pressure oil reservoir environment can be realized, and an imbibition rule, imbibition characteristics and imbibition efficiency in a formation oil injection liquid development process can be determined; and gas reservoir gas injection competes for adsorption rules, development characteristics, development efficiency and the like.

Description

Technical Field

[0001] This invention relates to the field of oil and gas reservoir development technology, specifically to an experimental apparatus and method for high-temperature and high-pressure oil reservoir permeation / gas reservoir competitive adsorption. Background Technology

[0002] my country possesses abundant reserves of tight oil, shale oil, tight gas, shale gas, and coalbed methane, with enormous future development potential. Due to the poor physical properties and low permeability of these reservoirs, capillary forces are significant, and adsorption is pronounced. Existing experimental research shows that the adsorption recovery rate of tight oil reservoirs can reach over 30%. In the development of tight oil and shale oil, adsorption is one of the most crucial mechanisms. For unconventional gas reservoirs such as tight gas, shale gas, and coalbed methane, studies have shown that the competitive adsorption of injected gas plays a significant role in enhancing natural gas recovery.

[0003] To clarify the role of percolation in the development of tight oil and shale oil, percolation tubes are commonly used for experimental research. However, currently used percolation tubes are glass tubes that cannot withstand high temperatures and pressures, and can only conduct percolation experiments at normal pressures and lower temperatures, failing to characterize the percolation process of oil reservoirs under high-temperature and high-pressure conditions during development. Currently, research on competitive adsorption in tight gas, shale gas, and coalbed methane often uses rock sample powder testing, which does not match actual gas reservoir conditions. The challenges in characterizing the percolation process in oil reservoirs under high-temperature and high-pressure conditions, and the competitive adsorption process in gas reservoirs, and further clarifying the percolation / competitive adsorption efficiency and elucidating the percolation / competitive adsorption mechanism, lie in: 1. How to successfully transfer cores saturated with formation oil (crude oil containing dissolved natural gas under formation conditions) or formation gas (gas in gas reservoirs under formation conditions) under high-temperature and high-pressure conditions into the percolation apparatus; 2. How to achieve a working environment for the percolation apparatus that matches the high-temperature and high-pressure formation environment.

[0004] Currently, the invention patent with authorization announcement number CN102360001B, entitled "Permeabilizer," includes a quartz cylindrical measuring chamber and a stainless steel cylindrical core chamber. Both the measuring chamber and the core chamber are made of pressure-resistant materials and are sealed together to form a tight, sealed system, enabling experimental research on the detection of permeabilization and deoiling rates under high pressure. However, it can only conduct high-pressure permeabilization experiments by transferring cores after they have been saturated with crude oil into the permeabilizer. At this point, the crude oil in the core has already been degassed to form surface oil, making it impossible to characterize the permeabilization process of saturated formation oil in the core under formation conditions. Furthermore, the crude oil metering system is made of quartz, which has limited pressure resistance, making it unsuitable for testing in ultra-deep reservoirs (such as 10,000-meter deep wells) under high-pressure conditions. How to study the permeabilization of tight oil and shale oil, as well as the competitive adsorption laws of tight gas, shale gas, and coalbed methane injection under high temperature and high pressure conditions in oil and gas reservoirs, has become an urgent problem to be solved. Summary of the Invention

[0005] To address the aforementioned shortcomings of existing technologies, this invention provides an experimental apparatus and method for high-temperature and high-pressure oil reservoir percolation / gas reservoir competitive adsorption, solving the problems that existing percolation instruments cannot perform percolation experiments under high-temperature and high-pressure conditions in oil reservoirs and competitive adsorption testers cannot perform competitive adsorption tests under high-temperature and high-pressure conditions in gas reservoirs.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: Firstly, an experimental apparatus is provided for high-temperature and high-pressure oil reservoir permeation / gas reservoir competitive adsorption, comprising: The experimental body located inside the constant temperature chamber includes an absorption shell and a clamping cylinder fixed inside the absorption shell. The bottom of the absorption shell is provided with an opening that communicates with the lower port of the clamping cylinder. A base plate is detachably provided at the opening. The upper and lower ends of the clamping cylinder are respectively sealed with a partition top cover and a partition base, forming a core filling chamber between the partition top cover and the partition base. A rotating push rod for pushing and pulling the partition base is provided on the base plate. Fasteners for abutting the top of the partition top cover are provided on the absorption shell. The injection system includes a confining pressure pump connected to the side wall of the core filling chamber, a first injection pump connected to the bottom of the core filling chamber, a first back pressure valve connected to the top of the core filling chamber, and a second injection pump and a second back pressure valve, both connected to the side wall of the seepage shell. The first back pressure valve and the second back pressure valve are connected to the first back pressure pump and the second back pressure pump respectively through ball valves. The metering and analysis system includes an absorption metering device and a gas meter, both connected to the second back pressure valve, with the absorption metering device and the gas meter connected together.

[0007] Furthermore, a T-shaped keyway is provided between the opening and the side wall of the base plate, and a locking key is fitted on the T-shaped keyway to fix the base plate at the opening; the rotating push rod is provided with external threads, the base plate is provided with threaded holes that mate with the external threads, the inner end of the rotating push rod is provided with a ball joint, and the bottom of the partition base is provided with a ball groove that mates with the ball joint.

[0008] Furthermore, the fastener includes several fastening rods located around the clamping cylinder. The fastening rods are sealed through the bottom of the permeation shell and rotatably mounted on the permeation shell. The inner end of the fastening rod is provided with a fastening buckle that abuts against the top of the partition cover, and the outer end of the fastening rod is provided with a fastening handle.

[0009] Furthermore, a first sealing ring is provided on the side wall near the outer end of the partition top cover and the partition base, and a second sealing ring with a flexible diaphragm is provided on the side wall near the inner end of the partition top cover and the partition base. The flexible diaphragm is attached to the side wall near the inner end of the partition top cover and the partition base, and the flexible diaphragm has a certain gap with the inner side wall of the clamping cylinder to form a confining pressure chamber.

[0010] Furthermore, the first injection pump is connected to the bottom of the core loading chamber through parallel formation oil / gas containers and formation water containers, the confining pressure pump is connected to the side wall of the core loading chamber through the confining pressure liquid container, and the second injection pump is connected to the side wall of the injection liquid / gas container through the seepage shell. Ball valves are installed at the inlet and outlet of the formation oil / gas container, formation water container, confining pressure liquid container and injection liquid / gas container.

[0011] Furthermore, the percolation metering device includes a metering cup inverted inside a liquid level stabilizer. The upper neck of the metering cup has a scale line, and the lower part of the metering cup is provided with a drain hole. An overflow hole is provided on the side wall of the liquid level stabilizer, and a liquid receiving groove is provided at the overflow hole. The second back pressure valve is connected to the middle part of the upper neck of the metering cup through a ball valve, and the top of the metering cup is connected to a gas metering device through a ball valve.

[0012] Furthermore, the first back pressure valve is connected to the gas meter via a gas-liquid separation device and a ball valve. The gas meter is connected to a gas chromatograph. A high-definition camera for recording the amount of oil absorbed is installed on one side of the neck of the measuring cup. The gas meter, the gas chromatograph, and the high-definition camera are all electrically connected to a computer.

[0013] Secondly, an experimental method based on an experimental apparatus for high-temperature and high-pressure oil reservoir permeation / gas reservoir competitive adsorption is provided, which includes an oil reservoir permeation experimental method, comprising the following steps: S1: After cleaning the core, test its porosity and permeability; inject the compounded formation oil and formation water into the formation oil / gas container and formation water container respectively under reservoir pressure; inject the reservoir injection fluid into the liquid / gas container. S2: Place the core in the core loading chamber, and use the rotating push rod to drive the partition base, core, and partition top cover to be tightly packed until the fasteners abut against the top of the partition top cover; S3: Inject confining pressure fluid into the confining pressure chamber using the confining pressure pump until the required experimental pressure is applied; inject reservoir injection fluid into the absorption chamber of the permeation shell using the second injection pump and purge the air from the chamber, and open the second back pressure pump and the second back pressure valve until the required experimental pressure is reached; close the second injection pump and increase the temperature of the experimental body to the experimental temperature using the constant temperature chamber; S4: Open the formation water container and inject formation water into the core filling chamber through the first injection pump; open the first back pressure pump to apply back pressure to the first back pressure valve to the pressure required for the experiment; after the core is saturated with formation water, heat it to the reservoir temperature through a constant temperature chamber and wait for a certain period of time until the core temperature is uniform and the formation water fully wets the core. S5: Close the formation water container, open the formation oil / gas container, and inject formation oil into the core filling chamber through the first injection pump until the gas-oil ratio of the formation oil discharged from the gas-liquid separator reaches the formation oil dissolved gas-oil ratio; heat to the experimental temperature through a constant temperature chamber and wait for a certain period of time to age the core. S6: By rotating the fastening handle until the top cover of the partition is disengaged from the fastening buckle, the core saturated with formation oil is driven out of the core filling chamber by rotating the push rod and placed in the reservoir injection fluid of the seepage shell absorption chamber; S7: The second injection pump injects reservoir injection fluid into the absorption chamber of the seepage shell at a certain rate until the reservoir injection fluid continuously drives the oil and dissolved gas seeping out of the core to the seepage metering device in real time through the second back pressure valve. The high-definition camera is turned on to record the change of the seepage oil volume over time. The seepage dissolved gas is measured in real time by the gas meter and gas phase component chromatograph, and the collected data is stored by the computer. S8: Extract data from each test point at the same time interval, and finally obtain the seepage and drainage efficiency of the test reservoir under high temperature and high pressure conditions.

[0014] An experimental method is provided based on an experimental apparatus for high-temperature and high-pressure oil reservoir permeation / gas reservoir competitive adsorption, which includes a gas reservoir competitive adsorption experimental method, comprising the following steps: A1: After placing the core in a vacuum drying oven for a certain period of time, test its weight, porosity and permeability at room temperature; A2: The mixed formation gas and formation water are injected into the formation oil / gas container and formation water container respectively under the gas reservoir pressure, and the gas reservoir injection gas is injected into the injection liquid / gas container; A3: Place the core in the core loading chamber, and use the rotating push rod to drive the partition base, core, and partition top cover to be tightly packed until the fasteners abut against the top of the partition top cover; A4: Inject confining pressure liquid into the confining pressure chamber using the confining pressure pump until the required experimental pressure is applied; inject gas into the gas reservoir of the permeation shell using the second injection pump and purge the air in the cavity, and open the second back pressure pump and the second back pressure valve until the required experimental pressure is reached; close the second injection pump and increase the temperature of the experimental body to the experimental temperature using the constant temperature chamber. A5: Open the formation oil / gas container, and while keeping the gas pressure inside the formation oil / gas container constant, inject formation gas into the core filling chamber through the first injection pump. Open the first back pressure pump to apply back pressure to the first back pressure valve to the required experimental pressure until the core is saturated with formation gas. Heat to the experimental temperature using a constant temperature chamber. A6: By rotating the fastening handle until the top cover of the partition is disengaged from the fastening buckle, the core saturated with formation gas is driven out of the core filling chamber by rotating the push rod and placed into the gas reservoir injection gas in the gas absorption chamber of the seepage shell. A7: The second injection pump injects gas into the absorption chamber of the seepage shell at a certain rate until the gas injection gas continuously drives the produced gas competitively adsorbed in the core to the gas meter and gas phase chromatograph in real time through the second back pressure valve. The produced gas is then measured in real time by the gas meter and gas phase chromatograph. A8: By acquiring the real-time composition of the produced gas through competitive adsorption using a computer, the real-time variation patterns of the formation gas components contained in the produced gas can be analyzed.

[0015] The beneficial effects of this invention are as follows: 1. This scheme solves the current problem of being unable to characterize the seepage and competitive adsorption processes under high temperature and high pressure conditions in oil and gas reservoirs. By integrating the saturated core process and the seepage and competitive adsorption processes into the same experimental device, it can simulate the high temperature and high pressure conditions of oil and gas reservoirs as well as the seepage and competitive adsorption processes. It avoids pressure loss and temperature changes during core transportation, ensuring the accuracy of experimental data. At the same time, through mechanical structures such as rotating push rods and several fastening rods, it realizes rapid loading and unloading of cores, thereby achieving rapid switching of cores from the core loading chamber to the absorption chamber, simplifying the experimental procedure.

[0016] 2. The percolation metering device, gas meter, and gas phase component chromatograph in this scheme enable real-time measurement and analysis of oil and gas components, improving the reliability of experimental results. At the same time, this scheme is applicable to the percolation and competitive adsorption studies of various unconventional oil and gas reservoirs such as tight oil, shale oil, tight gas, shale gas, and coalbed methane, providing important experimental means for oil and gas field development. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the experimental setup for high-temperature, high-pressure oil reservoir permeation / gas reservoir competitive adsorption.

[0018] Figure 2 This is a schematic diagram of the structure of the experimental subject.

[0019] Figure 3 for Figure 2 A schematic diagram of the structure at point A in the middle.

[0020] Figure 4 for Figure 2 A schematic diagram of the structure at point B.

[0021] Figure 5 for Figure 2 A schematic diagram of the structure at point C.

[0022] Figure 6 for Figure 2 A schematic diagram of the structure at point D.

[0023] Figure 7 for Figure 2A schematic diagram of the structure at point E in the middle.

[0024] Figure 8 This is a diagram showing the reservoir permeation efficiency under high temperature and high pressure conditions.

[0025] Among them, 101, first injection pump; 102, confining pressure pump; 103, second injection pump; 104, second back pressure pump; 105, first back pressure pump; 201-216, ball valves; 301, formation oil / gas container; 302, formation water container; 303, confining pressure liquid container; 304, injection liquid / gas container; 4, experimental body; 501, first back pressure valve; 502, second back pressure valve; 6, gas-liquid separation device; 7, gas metering device; 8, gas phase component chromatograph; 9, overflow hole; 10, liquid receiving tank; 11, liquid level constant; 12, percolation metering device; 13, drain. 14. Hole; 15. Tripod; 16. High-definition camera; 401. Computer; 402. Fastening handle; 403. Rotating push rod; 404. Partition base; 405. Clamping cylinder; 406. Core filling chamber; 407. Fastening buckle; 408. Partition top cover; 409. Constant temperature chamber; 410. Infiltration shell; 411. Absorption chamber; 412. Internal flow channel; 413. Connecting male connector; 414. Ball joint; 415. External thread; 416. First sealing ring; 417. Flexible diaphragm; 418. Confining pressure chamber; 419. T-shaped keyway; 410. Locking pin. Detailed Implementation

[0026] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0027] like Figures 1 to 7 As shown, the experimental setup for high-temperature, high-pressure reservoir permeation / gas reservoir competitive adsorption in this scheme includes: The experimental body 4, located inside the constant temperature chamber 408, includes an absorption shell 409 and a clamping cylinder 404 fixed inside the absorption shell 409. The bottom of the absorption shell 409 is provided with an opening that communicates with the lower port of the clamping cylinder 404. A base plate is detachably provided at the opening. The upper and lower ends of the clamping cylinder 404 are respectively sealed with a partition top cover 407 and a partition base 403, and a core filling chamber 405 is formed between the partition top cover 407 and the partition base 403. A rotating push rod 402 for pushing and pulling the partition base 403 is provided on the base plate. Fasteners for abutting the top of the partition top cover 407 are provided on the absorption shell 409. The injection system includes a confining pressure pump 102 connected to the side wall of the core filling chamber 405, a first injection pump 101 connected to the bottom of the core filling chamber 405, a first back pressure valve 501 connected to the top of the core filling chamber 405, and a second injection pump 103 and a second back pressure valve 502, both connected to the side wall of the permeation shell 409. The first back pressure valve 501 and the second back pressure valve 502 are connected to the first back pressure pump 105 and the second back pressure pump 104 respectively through ball valve 210 and ball valve 209. In practice, the connection between the core filling chamber 405 and the permeation shell 409 is composed of an internally hollow connecting male connector 412 and a flow channel 411.

[0028] The metering and analysis system includes an absorption metering device 12 and a gas meter 7, both of which are connected to the second back pressure valve 502, and the absorption metering device 12 is connected to the gas meter 7.

[0029] In specific implementation, a T-shaped keyway 418 is provided between the opening and the side wall of the base plate, and a locking key 419 for fixing the base plate at the opening is fitted on the T-shaped keyway 418; an external thread 414 is provided on the rotating push rod 402, a threaded hole that mates with the external thread 414 is provided on the base plate, a ball joint 413 is provided on the inner end of the rotating push rod 402, and a ball groove that mates with the ball joint 413 is provided at the bottom of the partition base 403.

[0030] The fasteners include four fastening rods located around the clamping cylinder 404. All four fastening rods are sealed through the bottom of the seepage housing 409 and are rotatably mounted on the seepage housing 409. The inner end of the fastening rod is provided with a fastening buckle 406 that abuts against the top of the partition cover 407, and the outer end of the fastening rod is provided with a fastening handle 401.

[0031] A first sealing ring 415 is provided on the side wall of the partition top cover 407 and the partition base 403 near the outer end, and a second sealing ring with a flexible diaphragm 416 is provided on the side wall of the partition top cover 407 and the partition base 403 near the inner end. The flexible diaphragm 416 is attached to the side wall of the partition top cover 407 and the partition base 403 near the inner end. The flexible diaphragm 416 has a certain gap with the inner side wall of the clamping cylinder 404 and forms a confining pressure chamber 417.

[0032] The first injection pump 101 is connected to the bottom of the core loading chamber 405 through the parallel formation oil / gas container 301 and formation water container 302. The confining pressure pump 102 is connected to the side wall of the core loading chamber 405 through the confining pressure liquid container 303. The second injection pump 103 is connected to the side wall of the seepage shell 409 of the injection liquid / gas container 304. Ball valves 201 and 203 are respectively installed at the inlet and outlet of the formation oil / gas container 301. Ball valves 202 and 204 are respectively installed at the inlet and outlet of the formation water container 302. Ball valves 205 and 206 are respectively installed at the inlet and outlet of the confining pressure liquid container 303. Ball valves 207 and 208 are respectively installed at the inlet and outlet of the injection liquid / gas container 304.

[0033] The percolation metering device 12 includes a metering cup inverted inside the liquid level constant device 11. The upper neck of the metering cup has a scale line, and the lower part of the metering cup is provided with a drain hole 13. The side wall of the liquid level constant device 11 is provided with an overflow hole 9, and a liquid receiving groove 10 is provided at the overflow hole 9. The second back pressure valve 502 is connected to the middle part of the upper neck of the metering cup through a ball valve 216, and the top of the metering cup is connected to the gas metering device 7 through a ball valve 212.

[0034] The first back pressure valve 501 is connected to the gas meter 7 via the gas-liquid separation device 6 and the ball valve 211. The gas meter 7 is connected to the gas chromatograph 8. A high-definition camera 15 for recording the amount of oil absorbed is installed on one side of the neck of the measuring cup. The high-definition camera 15 is fixed by the tripod 14. The gas meter 7, the gas chromatograph 8 and the high-definition camera 15 are all electrically connected to the computer 16.

[0035] This scheme also provides an experimental method based on an experimental apparatus for high-temperature and high-pressure oil reservoir permeation / gas reservoir competitive adsorption, which includes an oil reservoir permeation experimental method and a gas reservoir competitive adsorption experimental method.

[0036] The reservoir permeation test method specifically includes the following steps: S1: After cleaning the standard core (2.5cm in diameter and 5cm in length), test the porosity and permeability. Inject the compounded formation oil and formation water into the formation oil / gas container 301 and formation water container 302 respectively under reservoir pressure. S2: Rotate the locking pin 419 90°, remove the bottom plate at the bottom of the seepage shell, use the rotating push rod 402 to pull out the partition base 403, and put in the cleaned core; put the high temperature clamping cylinder 404 in the order of partition top cover 407 - core - partition base 403, and then install the locking pin 419 back into the T-shaped keyway 418; S3: Rotate the fastening handle 401 clockwise, and drive the partition base 403, core and partition top cover 407 to be tightly filled by rotating the push rod 402 until the fastening buckle 406 abuts against the top of the partition top cover 407. S4: Turn on the confining pressure pump 102 to inject confining pressure liquid into the confining pressure chamber 417, apply the confining pressure to the pressure required for the experiment, and use the high temperature and high pressure resistant flexible diaphragm 416 and the first sealing ring 415 and the fastening handle 401 on the partition top cover 407 and the partition base 403 to seal the core in the core filling chamber 405. S5: Open the front and rear ball valves 207 and 208 of the injection liquid / gas container 304, turn on the second injection pump 103 to inject reservoir injection liquid into the absorption chamber 410 and purge the air in the cavity, turn on the second back pressure pump 104 and set it to the pressure required for the experiment, start the second back pressure valve 502 to make the pressure in the absorption chamber 410 the pressure required for the experiment, and then close the second injection pump 103 and the front and rear ball valves 207 and 208 of the intermediate container 304, and increase the temperature of the constant temperature chamber 408 to the experimental temperature; S6: After the temperature and pressure of the entire system reach the required temperature and pressure for the experiment, open the ball valves 202 and 204 before and after the formation water container 302, close the ball valves 201 and 203 before and after the formation oil / gas container 301, inject formation water into the core filling chamber 405 at an injection rate of 0.1 ml / min, open the first back pressure pump 105 to increase the back pressure of the first back pressure valve 501 to the required pressure for the experiment, and after the formation water is saturated, heat the constant temperature chamber to the reservoir temperature for 48 hours to ensure that the formation water fully wets the core and the core temperature reaches uniformity; S7: Close the ball valves 202 and 204 before and after the formation water container 302, and open the ball valve 201 before the formation oil / gas container 301 to gradually increase the pressure in the formation oil / gas container 301 to the pressure required for the experiment; S8: After the pressure in the formation oil / gas container 301 reaches the experimental pressure, open the ball valve 203 after the formation oil / gas container 301, and inject formation crude oil (saturated dissolved gas crude oil) into the core at an injection rate of 0.1 ml / min until the gas-oil ratio at the outlet reaches the formation oil dissolved gas-oil ratio. Heat the constant temperature chamber to the experimental temperature for 48 hours so that the system temperature and pressure reach the experimental conditions. Place the saturated core in the constant temperature chamber for aging for more than 7 days to simulate the reservoir environment. S9: Close the ball valve 203, rotate the fastening handle 401 180°, and open the upper partition cover 407 of the high-temperature clamping cylinder 404; S10: Rotate push rod 402 clockwise to push half of the core out of the core cavity, rotate the seepage shell 409 to slide the partition top cover 407 into the absorption chamber 410, then adjust the outer shell 409 of the absorption chamber device to be perpendicular to the horizontal plane, and continue to rotate push rod 402 until the core is completely pushed out of the core saturation cavity, so that the core saturated with formation oil is placed in the reservoir injection fluid; S11: Open the front and rear ball valves 207 and 208 of the injection liquid / gas container 304, and turn on the second injection pump 103 to continuously inject reservoir injection liquid into the absorption chamber 410 at a rate of 0.1 ml / min; S12: The reservoir injection fluid continuously drives the oil and dissolved gas that seep out of the core to the seepage metering device 12 in real time through the second back pressure valve 502. After preliminary separation, the excess seepage fluid flows into the liquid level constant device 11 from the lower discharge hole 13 under the action of gravity separation, and then flows into the liquid receiving tank 10 from the overflow hole 9. The seepage gas moves upward and enters the gas metering device 7 through the ball valve 212 for measurement. The recorded data will be transmitted to the computer for storage in real time. S13: Turn on the high-definition camera 15 to record the change in the amount of oil absorbed over time; S14: Extract data collected by high-definition camera 15 and gas meter 7. Extract data from each test point at the same time interval. Finally, obtain the seepage and drainage efficiency of the test reservoir under high temperature and high pressure conditions. The experimental results are as follows: Figure 8 As shown.

[0037] The competitive adsorption experimental method for gas reservoirs in this scheme specifically includes the following steps: A1: Place a standard rock core or coal core (2.5cm in diameter and 5cm in length) in a vacuum drying oven, heat it to 80℃ and keep it at that temperature for 8 hours. After cooling to room temperature, weigh it and test its porosity and permeability. A2: The compounded formation gas and formation water are injected into the formation oil / gas container 301 and formation water container 302 respectively under the gas reservoir pressure; A3: Rotate the locking pin 419 90°, remove the bottom plate of the seepage shell, use the rotating push rod 402 to pull out the partition base 403, and put in the cleaned core; put the high temperature clamping cylinder 404 in the order of partition top cover 407 - core - partition base 403, and then install the locking pin 419 back into the T-shaped keyway 418; A4: Rotate the fastening handle 401 clockwise to drive the partition base 403, core and partition top cover 407 to be tightly packed by rotating the push rod 402 until the fastening buckle 406 abuts against the top of the partition top cover 407. A5: Turn on the confining pressure pump 102 to inject confining pressure liquid into the confining pressure chamber 417, apply the confining pressure to the pressure required for the experiment, and use the high temperature and high pressure resistant flexible diaphragm 416 of the partition top cover 407 and the partition base 403, the first sealing ring 415, and the fastening handle 401 to seal the core in the core filling chamber 405. A6: Open the front and rear ball valves 207 and 208 of the injection liquid / gas container 304, turn on the second injection pump 103 to inject gas into the gas reservoir into the absorption chamber 410 and vent the air in the cavity, turn on the second back pressure pump 104 and set it to the pressure required for the experiment, start the second back pressure valve 502 to make the pressure in the absorption chamber 410 the pressure required for the experiment, and then close the second injection pump 103 and the front and rear ball valves 207 and 208 of the intermediate container 304, and increase the temperature of the constant temperature chamber 408 to the experimental temperature; A7: After the temperature and pressure of the entire system reach the required temperature and pressure for the experiment, open the ball valves 201 and 203 before and after the formation oil / gas container 301. While keeping the gas pressure in the intermediate container constant, slowly inject formation gas into the core in the core filling chamber 405. Open the first back pressure pump 105 to increase the back pressure of the first back pressure valve 501 to the required pressure for the experiment. After the pressure in the core reaches the required pressure for the experiment, produce more than 5PV of formation gas. Ensure that the gas phase composition in the produced gas is the same as that of the formation gas. Then maintain the system pressure for 24 hours, which is considered as adsorption saturation. At the same time as gas injection, heat the constant temperature box to the reservoir temperature to complete the core saturation formation gas process. A8: Close the first injection pump 101 and ball valve 203, rotate the fastening handle 401 180°, and open the upper partition top cover 407 of the high temperature clamping cylinder 404. A9: Rotate push rod 402 clockwise to push half of the core out of the core cavity, rotate the outer shell 409 of the absorption chamber device to slide the partition top cover 407 into the absorption chamber 410, then adjust the outer shell 409 of the absorption chamber device to be perpendicular to the horizontal plane, and continue to rotate push rod 402 until the core is completely pushed out of the core saturation cavity, so that the core saturated with formation oil is placed in the gas injection gas of the gas reservoir; A10: Open the ball valves 207 and 208 before and after the injection liquid / gas container 304, and turn on the second injection pump 103 to continuously inject gas into the absorption chamber 410 at a rate of 0.1 ml / min; A11: The gas injected into the gas reservoir continuously drives out the produced gas competitively adsorbed in the core through the second back pressure valve 502 in real time from the absorption chamber 410, and then passes through the ball valve 215, gas meter 7, ball valve 214 and gas phase component chromatograph 8 in sequence. The produced gas is measured in real time by the gas meter 7 and the gas phase component chromatograph 8. A12: After data processing, the real-time competitive adsorption components of the produced gas can be obtained through computer 16. This allows for analysis of the real-time variation of formation gas components in the produced gas, and exploration of the impact of competitive adsorption of injected gas on gas recovery rate and adsorption characteristics under high temperature and high pressure conditions in the gas reservoir.

[0038] In summary, this scheme solves the current problem of being unable to characterize the percolation and competitive adsorption processes under high temperature and high pressure conditions in oil and gas reservoirs. By integrating the saturated core process and the percolation and competitive adsorption processes into the same experimental device, it can simulate the high temperature and high pressure conditions of oil and gas reservoirs as well as the percolation and competitive adsorption processes, avoiding pressure loss and temperature changes during core transportation and ensuring the accuracy of experimental data.

Claims

1. An experimental apparatus for high-temperature and high-pressure oil reservoir percolation / gas reservoir competitive adsorption, characterized in that, include: The experimental body located inside the constant temperature chamber includes an absorption shell and a clamping cylinder fixed inside the absorption shell. The bottom of the absorption shell is provided with an opening that communicates with the lower port of the clamping cylinder. A base plate is detachably provided at the opening. The upper and lower ends of the clamping cylinder are respectively sealed with a partition top cover and a partition base, forming a core filling chamber between the partition top cover and the partition base. A rotating push rod for pushing and pulling the partition base is provided on the base plate. Fasteners for abutting against the top of the partition top cover are provided on the absorption shell. The injection system includes a confining pressure pump connected to the side wall of the core filling chamber, a first injection pump connected to the bottom of the core filling chamber, a first back pressure valve connected to the top of the core filling chamber, and a second injection pump and a second back pressure valve, both connected to the side wall of the seepage shell. The first back pressure valve and the second back pressure valve are connected to the first back pressure pump and the second back pressure pump respectively through ball valves. The metering and analysis system includes an absorption metering device and a gas meter, both connected to the second back pressure valve, with the absorption metering device and the gas meter connected together.

2. The experimental apparatus for high-temperature and high-pressure oil reservoir permeation / gas reservoir competitive adsorption according to claim 1, characterized in that, A T-shaped keyway is provided between the opening and the side wall of the base plate, and a locking key is fitted on the T-shaped keyway to fix the base plate at the opening; the rotating push rod is provided with an external thread, the base plate is provided with a threaded hole that mates with the external thread, the inner end of the rotating push rod is provided with a spherical joint, and the bottom of the partition base is provided with a spherical groove that mates with the spherical joint.

3. The experimental apparatus for high-temperature and high-pressure oil reservoir permeation / gas reservoir competitive adsorption according to claim 1, characterized in that, The fastener includes several fastening rods located around the clamping cylinder. Each of the fastening rods is sealed through the bottom of the absorbent housing and is rotatably mounted on the absorbent housing. The inner end of each fastening rod is provided with a fastening buckle that abuts against the top of the partition cover, and the outer end of each fastening rod is provided with a fastening handle.

4. The experimental apparatus for high-temperature and high-pressure oil reservoir permeation / gas reservoir competitive adsorption according to claim 1, characterized in that, A first sealing ring is provided on the side wall near the outer end of the partition top cover and the partition base, and a second sealing ring with a flexible diaphragm is provided on the side wall near the inner end of the partition top cover and the partition base. The flexible diaphragm is attached to the side wall near the inner end of the partition top cover and the partition base. The flexible diaphragm has a certain gap with the inner side wall of the clamping cylinder and forms a confining pressure chamber.

5. The experimental apparatus for high-temperature and high-pressure oil reservoir permeation / gas reservoir competitive adsorption according to claim 1, characterized in that, The first injection pump is connected to the bottom of the core loading chamber through parallel formation oil / gas containers and formation water containers. The confining pressure pump is connected to the side wall of the core loading chamber through a confining pressure fluid container. The second injection pump is connected to the side wall of the injection liquid / gas container through the seepage shell. Ball valves are provided at the inlet and outlet of the formation oil / gas container, formation water container, confining pressure fluid container, and injection liquid / gas container.

6. The experimental apparatus for high-temperature and high-pressure oil reservoir permeation / gas reservoir competitive adsorption according to claim 1, characterized in that, The percolation metering device includes a metering cup inverted inside a liquid level constanter. The upper neck of the metering cup has a scale line, and the lower part of the metering cup is provided with a drain hole. An overflow hole is provided on the side wall of the liquid level constanter, and a liquid receiving groove is provided at the overflow hole. The second back pressure valve is connected to the middle part of the upper neck of the metering cup through a ball valve, and the top of the metering cup is connected to a gas metering device through a ball valve.

7. The experimental apparatus for high-temperature and high-pressure oil reservoir permeation / gas reservoir competitive adsorption according to claim 6, characterized in that, The first back pressure valve is connected to a gas meter via a gas-liquid separation device and a ball valve. The gas meter is connected to a gas chromatograph. A high-definition camera for recording the amount of oil absorbed is installed on one side of the neck of the measuring cup. The gas meter, the gas chromatograph, and the high-definition camera are all electrically connected to a computer.

8. An experimental method based on an experimental setup for high-temperature, high-pressure oil reservoir permeation / gas reservoir competitive adsorption, characterized in that, This includes reservoir permeation testing methods, which include the following steps: S1: After cleaning the core, test its porosity and permeability; inject the compounded formation oil and formation water into the formation oil / gas container and formation water container respectively under reservoir pressure; inject the reservoir injection fluid into the liquid / gas container. S2: Place the core in the core loading chamber, and use the rotating push rod to drive the partition base, core, and partition top cover to be tightly packed until the fasteners abut against the top of the partition top cover; S3: Inject confining pressure fluid into the confining pressure chamber using the confining pressure pump until the required experimental pressure is applied; inject reservoir injection fluid into the absorption chamber of the permeation shell using the second injection pump and purge the air from the chamber, and open the second back pressure pump and the second back pressure valve until the required experimental pressure is reached; close the second injection pump and increase the temperature of the experimental body to the experimental temperature using the constant temperature chamber; S4: Open the formation water container and inject formation water into the core filling chamber through the first injection pump; open the first back pressure pump to apply back pressure to the first back pressure valve to the pressure required for the experiment; after the core is saturated with formation water, heat it to the reservoir temperature through a constant temperature chamber and wait for a certain period of time until the core temperature is uniform and the formation water fully wets the core. S5: Close the formation water container, open the formation oil / gas container, and inject formation oil into the core filling chamber through the first injection pump until the gas-oil ratio of the formation oil discharged from the gas-liquid separator reaches the formation oil dissolved gas-oil ratio; heat to the experimental temperature through a constant temperature chamber and wait for a certain period of time to age the core. S6: By rotating the fastening handle until the top cover of the partition is disengaged from the fastening buckle, the core saturated with formation oil is driven out of the core filling chamber by rotating the push rod and placed in the reservoir injection fluid of the seepage shell absorption chamber; S7: The second injection pump injects reservoir injection fluid into the absorption chamber of the seepage shell at a certain rate until the reservoir injection fluid continuously drives the oil and dissolved gas seeping out of the core to the seepage metering device in real time through the second back pressure valve. The high-definition camera is turned on to record the change of the seepage oil volume over time. The seepage dissolved gas is measured in real time by the gas meter and gas phase component chromatograph, and the collected data is stored by the computer. S8: Extract data from each test point at the same time interval, and finally obtain the seepage and drainage efficiency of the test reservoir under high temperature and high pressure conditions.

9. An experimental method based on an experimental setup for high-temperature, high-pressure oil reservoir permeation / gas reservoir competitive adsorption, characterized in that, This includes a gas reservoir competitive adsorption experimental method, which comprises the following steps: A1: After placing the core in a vacuum drying oven for a certain period of time, test its weight, porosity and permeability at room temperature; A2: The mixed formation gas and formation water are injected into the formation oil / gas container and formation water container respectively under the gas reservoir pressure, and the gas reservoir injection gas is injected into the injection liquid / gas container; A3: Place the core in the core loading chamber, and use the rotating push rod to drive the partition base, core, and partition top cover to be tightly packed until the fasteners abut against the top of the partition top cover; A4: Inject confining pressure liquid into the confining pressure chamber using the confining pressure pump until the required experimental pressure is applied; inject gas into the gas reservoir of the permeation shell using the second injection pump and purge the air in the cavity, and open the second back pressure pump and the second back pressure valve until the required experimental pressure is reached; close the second injection pump and increase the temperature of the experimental body to the experimental temperature using the constant temperature chamber. A5: Open the formation oil / gas container, and while keeping the gas pressure inside the formation oil / gas container constant, inject formation gas into the core filling chamber through the first injection pump. Open the first back pressure pump to apply back pressure to the first back pressure valve to the required experimental pressure until the core is saturated with formation gas. Heat to the experimental temperature using a constant temperature chamber. A6: By rotating the fastening handle until the top cover of the partition is disengaged from the fastening buckle, the core saturated with formation gas is driven out of the core filling chamber by rotating the push rod and placed into the gas reservoir injection gas in the gas absorption chamber of the seepage shell. A7: The second injection pump injects gas into the absorption chamber of the seepage shell at a certain rate until the gas injection gas continuously drives the produced gas competitively adsorbed in the core to the gas meter and gas phase chromatograph in real time through the second back pressure valve. The produced gas is then measured in real time by the gas meter and gas phase chromatograph. A8: By acquiring the real-time composition of the produced gas through competitive adsorption using a computer, the real-time variation patterns of the formation gas components contained in the produced gas can be analyzed.

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