Device and method for monitoring migration of injected gas of dip angle oil reservoir

Abstract

The invention provides an inclination angle oil reservoir injected gas migration monitoring device and method, and belongs to the technical field of oil and gas reservoir development, the device comprises a high pressure injection pump, a water medium container, a gas medium container, a crude oil medium container, an inclination angle simulator, an acquisition module and a data processing module; the high-pressure injection pump is used for respectively controlling the water medium container to introduce water into the inclination angle simulator, controlling the crude oil medium container to introduce gas-containing crude oil and gas-free crude oil into the inclination angle simulator, and controlling the gas medium container to introduce target gas into the inclination angle simulator; and the data processing module is used for acquiring migration tracks of the target gas in the porous medium at different inclination angles based on the mixture. When the device provided by the invention is applied to oil exploitation, the target gas migration rule in different oil reservoir environments can be simulated, so that the injection mode is optimized, the gas channeling occurrence time is slowed down, and the oil and gas recovery efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas reservoir development, and in particular relates to a device and method for monitoring the migration of injected gas in an inclined oil reservoir. Background Art

[0002] Before the exploitation of oil reservoirs, the gas migration characteristics in the reservoirs are generally analyzed in advance. At present, the analysis of oil reservoirs is a one-dimensional simulation of the reservoirs. Different rock layers in the reservoirs have different permeabilities. In the reservoirs, there are various rock pores and cracks, through which gas can penetrate or leak out. In one-dimensional simulation, it is impossible to accurately simulate these vertical penetration or leakage phenomena, which may lead to estimation errors in gas flow. The vertical gas movement has an important impact on the pressure distribution in the reservoir. It only solves the problem of gas channeling that may occur during long-distance migration, and cannot accurately simulate this pressure distribution. The reservoir is a complex dynamic system involving the interaction of multiple factors, such as permeability changes, pressure changes, and fluid interactions.

[0003] Although one-dimensional simulation devices are helpful in understanding and controlling gas channeling problems, they cannot fully reflect the complexity of real reservoirs and cannot fully consider these dynamic changes due to their simplification of reservoirs, which limits the accurate description of reservoir gas behavior and has a significant impact on the development effect of oil and gas reservoirs. Summary of the invention

[0004] In view of the above problems, the embodiments of the present application provide a device and method for monitoring the migration of injected gas in an inclined oil reservoir, so as to overcome the above problems or at least partially solve the above problems.

[0005] The embodiment of the present application provides a device for monitoring migration of injected gas in an inclined oil reservoir, the device comprising: a high-pressure injection pump, a water medium container, a gas medium container, a crude oil medium container, an inclination simulator, a collection module and a data processing module; wherein a porous medium is placed in the inclination simulator;

[0006] The high-pressure injection pump is connected to the inlet valves of the water medium container, the gas medium container and the crude oil medium container respectively, and the outlet valves of the water medium container, the gas medium container and the crude oil medium container are connected to the inclination simulator respectively;

[0007] The high-pressure injection pump is used to control the water medium container to introduce water into the inclination simulator, the crude oil medium container to introduce gas-containing crude oil and gas-free crude oil into the inclination simulator, and to control the gas medium container to introduce target gas into the inclination simulator; wherein the water, the gas-containing crude oil, and the gas-free crude oil flow into the porous medium to form an oil reservoir environment, and the target gas is used to displace the gas-containing crude oil in the oil reservoir environment;

[0008] The inclination simulator is used to control the inclination of the porous medium to simulate the migration of the target gas in the reservoir environment at different inclinations;

[0009] The acquisition module is connected to the inclination simulator and is used to collect a mixture of the target gas flowing out of the reservoir environment during the migration of the porous medium, wherein the mixture includes: the water, the gas-containing crude oil and the gas-free crude oil;

[0010] The data processing module is used to obtain the migration trajectory of the target gas in the porous medium at different inclination angles based on the mixture.

[0011] Optionally, the device further comprises: a gas-liquid separation meter, the gas-liquid separation meter being connected between the acquisition module and the data processing module;

[0012] The gas-liquid separation meter is used to perform gas-liquid separation on the mixture, obtain dynamic data of the mixture, and transmit the dynamic data to the data processing module; wherein the dynamic data includes the volume of the water and the volume of the gas-free crude oil;

[0013] The data processing module is used to calculate the volume of the water and the volume of the gas-free crude oil to obtain the migration trajectory of the target gas in the porous medium at different inclination angles.

[0014] Optionally, the device further comprises a control panel, and the control panel is connected to the inclination simulator and the acquisition module respectively;

[0015] The control panel is used to control the temperature and pressure inside the inclination simulator, the inclination of the porous medium, and the sampling time of the acquisition module.

[0016] Optionally, the tilt simulator comprises: an upper rubber sleeve and a lower rubber sleeve;

[0017] Among them, the upper rubber sleeve has a protrusion, the lower rubber sleeve has a groove, the protrusion and the groove are embedded in each other to form a rubber sleeve, and the porous medium is wrapped in the rubber sleeve.

[0018] Optionally, the inclination simulator further comprises: a clamp and a motor, wherein the clamp is fixedly mounted on the outside of the rubber sleeve; wherein a rotating bearing is mounted between the clamp and the motor, wherein one end of the rotating bearing is connected to the output end of the motor, and the other end is connected to the clamp;

[0019] The motor is used to output power to the rotating bearing so that the rotating bearing rotates the clamp;

[0020] The rubber sleeve is used to rotate under the drive of the clamp to change the inclination angle of the porous medium.

[0021] Optionally, the inclination simulator comprises at least one production outlet, the production outlet is connected to the collection module and communicated with the interior of the inclination simulator, and the device further comprises: a back pressure pump, the back pressure pump is connected to the inclination simulator;

[0022] The back-pressure pump is used to control the internal environmental pressure of the inclination simulator, so as to drive the mixture in the reservoir environment to flow out from the production port under the internal and external pressures of the inclination simulator.

[0023] Optionally, the upper rubber sleeve is provided with a plurality of extraction ports, the upper end of the clamp is provided with a sealing cover plate, and the extraction ports are opened on the sealing cover plate; wherein one extraction port corresponds to one extraction port.

[0024] In a second aspect of the embodiments of the present invention, a method for monitoring the migration of injected gas in an inclined oil reservoir is provided, which is applied to the device for monitoring the migration of injected gas in an inclined oil reservoir described in the first aspect of the embodiments of the present invention, wherein the device comprises: a high-pressure injection pump, a water medium container, a gas medium container, a crude oil medium container, an inclination simulator and a back pressure pump; wherein a porous medium is placed in the inclination simulator; and the method comprises:

[0025] Controlling the water medium container to inject water into the porous medium to simulate formation water saturation;

[0026] Controlling the crude oil medium container to inject gas-free crude oil into the porous medium to displace the water, so as to form bound water in the internal pores of the porous medium;

[0027] Controlling the crude oil medium container to inject gas-containing crude oil into the porous medium to construct an oil reservoir environment; wherein the water, the gas-containing crude oil, and the gas-free crude oil flow into the porous medium to form the oil reservoir environment;

[0028] The inclination simulator is controlled to change the inclination of the porous medium, so as to simulate the migration trajectory of the target gas in the reservoir environment at different inclinations.

[0029] Optionally, before controlling the inclination simulator to change the inclination of the porous medium to simulate the migration trajectory of the target gas in the reservoir environment at different inclinations, the method further includes:

[0030] An aging treatment is performed on the gas-bearing crude oil in the oil reservoir environment.

[0031] Optionally, before controlling the water medium container to inject water into the porous medium to simulate formation water saturation, the method further includes:

[0032] Performing vacuum treatment on the porous medium to remove air from the porous medium;

[0033] In the process of controlling the crude oil medium container to inject gas-containing crude oil into the porous medium to construct the reservoir environment, the method further includes:

[0034] The pressure of the back pressure pump is controlled to be higher than the injection end pressure of the high pressure injection pump, and the pressure is controlled to be higher than the oil saturation pressure of the gas-containing crude oil.

[0035] The device provided by the present invention mainly has the following advantages:

[0036] 1. First, place the porous medium in the inclination simulator, and use a high-pressure injection pump to control the water medium container to introduce water into the inclination simulator, and the crude oil medium container to introduce gas-containing crude oil and gas-free crude oil into the inclination simulator, so as to construct an oil reservoir environment. The oil reservoir environment can more accurately describe the geological conditions and oil reservoir structure. The device provided by the present invention can more accurately simulate the fluid flow. Compared with one-dimensional simulation, the migration law of the target gas in the gas injection development process under three-dimensional conditions can better reflect the complexity and diversity of the real oil reservoir, thereby improving the accuracy.

[0037] 2. Since the inclination simulator can control the inclination of porous media, the gas medium container is controlled by a high-pressure injection pump to introduce the target gas into the inclination simulator. Therefore, the gas migration law in porous media under different inclination angles considering the effect of gravity can be simulated, which is closer to the development law under the actual reservoir environment. In this way, the migration trajectory of the target gas can be obtained, so that the staff can optimize the injection method according to the gas migration law in different reservoir environments in actual applications, control the production oil-gas ratio increase rate, slow down the occurrence time of gas channeling, and improve the oil and gas recovery rate.

[0038] 3. In addition, there is a rubber sleeve in the inclination simulator. Placing the porous medium in the rubber sleeve can effectively block the fluid backflow corrosion in the porous medium, prevent the carbonated water solution formed during the target gas displacement experiment from corroding the clamp, reduce the risk factor during the experiment, and improve durability. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0040] Figure 1 is a schematic diagram of a device for monitoring migration of injected gas in an inclined oil reservoir provided in an embodiment of the present application;

[0041] Figure 2 It is a schematic diagram of the principle of a device for monitoring migration of injected gas in an inclined oil reservoir provided in an embodiment of the present application;

[0042] Figure 3 is a side view of a rubber sleeve provided in an embodiment of the present application;

[0043] Figure 4 is a top view of the interior of a tilt simulator provided in an embodiment of the present application;

[0044] Figure 5 is a top view of the exterior of a tilt simulator provided in an embodiment of the present application;

[0045] Figure 6 is a front view of the exterior of a tilt simulator provided in an embodiment of the present application;

[0046] Figure 7 It is a flowchart of the steps of a method for monitoring migration of injected gas in an inclined oil reservoir provided in an embodiment of the present application;

[0047] Figure 8 This is a migration diagram of carbon dioxide at an inclination angle of 50° provided in an embodiment of the present application;

[0048] Fig. 9 This is a migration diagram of carbon dioxide at an inclination angle of 25° provided in an embodiment of the present application;

[0049] Fig.10 This is a migration diagram of carbon dioxide at an inclination angle of 0° provided in an embodiment of the present application;

[0050] Description of reference numerals:

[0051] 1-high-pressure injection pump; 2-water medium container; 3-gas medium container; 4-crude oil medium container; 5-inclination simulator; 6-acquisition module; 7-data processing module; 8-porous medium; 9-gas-liquid separation meter; 10-back pressure pump; 11-control panel; 12-heat-resistant and pressure-resistant steel pipeline; 501-upper part of rubber sleeve; 502-lower part of rubber sleeve; 503-rotating shaft; 504-motor; 505-sealing plate; 506-suspension arm; 507-turntable; 5051-insulating pull rod; 5052-sealing nut. DETAILED DESCRIPTION

[0052] The exemplary embodiments of the present application will be described in more detail below in conjunction with the accompanying drawings in the embodiments of the present application. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present application and to enable the scope of the present application to be fully communicated to those skilled in the art.

[0053] Embodiment 1

[0054] Reference Figure 1 , Figure 1 This is a schematic diagram of a device for monitoring the migration of injected gas in an inclined oil reservoir provided in an embodiment of the present application, wherein the device comprises: a high-pressure injection pump, a water medium container, a gas medium container, a crude oil medium container, an inclination simulator, an acquisition module and a data processing module; wherein a porous medium is placed in the inclination simulator; the high-pressure injection pump is respectively connected to the inlet valves of the water medium container, the gas medium container and the crude oil medium container, and the outlet valves of the water medium container, the gas medium container and the crude oil medium container are respectively connected to the inclination simulator; the high-pressure injection pump is used to respectively control the water medium container to introduce water into the inclination simulator, the crude oil medium container to introduce gas-containing crude oil and gas-free crude oil into the inclination simulator, and to control the gas The medium container introduces the target gas into the inclination simulator; wherein the water, the gas-containing crude oil and the gas-free crude oil flow into the porous medium to form an oil reservoir environment, and the target gas is used to displace the gas-containing crude oil in the oil reservoir environment; the inclination simulator is used to control the inclination of the porous medium to simulate the migration of the target gas in the oil reservoir environment at different inclinations; the acquisition module is connected to the inclination simulator, and is used to produce a mixture flowing out of the oil reservoir environment during the migration of the target gas in the porous medium, and the mixture includes: the water, the gas-containing crude oil and the gas-free crude oil; the data processing module is used to obtain the migration trajectory of the target gas in the porous medium at different inclinations based on the mixture.

[0055] In this embodiment, refer to Figure 1 , Figure 1 Schematic diagram of a gas migration monitoring device for an inclined oil reservoir provided in an embodiment of the present application, the device comprises: a high-pressure injection pump 1, a water medium container 2, a gas medium container 3, a crude oil medium container 4, an inclination simulator 5, a collection module 6 and a data processing module 7, wherein a porous medium 8 is placed in the inclination simulator. The water medium container 2, the gas medium container 3 and the crude oil medium container 4 in this embodiment are all high-temperature and high-pressure medium containers.

[0056] The high-pressure injection pump 1 is connected to the inlet valves of the water medium container 2, the gas medium container 3 and the crude oil medium container 4 respectively, specifically by adopting a heat-resistant and pressure-resistant steel pipeline. The high-pressure injection pump can generate high pressure. By injecting pressure into the inlet valves of the water medium container 2, the gas medium container 3 and the crude oil medium container 4 respectively through the high-pressure transfer pump 1, the medium in each container can be transferred to the outlet valve.

[0057] Since the outlet valves of the water medium container 2, the gas medium container 3 and the crude oil medium container 4 are respectively connected to the inclination simulator 5, the high-pressure injection pump 1 controls the water medium container 2 to introduce water into the inclination simulator 5, the crude oil medium container 4 to introduce gas-containing crude oil and gas-free crude oil into the inclination simulator 5, and controls the gas medium container 3 to introduce the target gas into the inclination simulator 5. In this embodiment, the target gas can be any one of carbon dioxide, nitrogen and methane. By flowing water, gas-containing crude oil and gas-free crude oil into the porous medium 8, an oil reservoir environment can be formed. The oil reservoir environment is used to simulate the real oil reservoir structure. The target gas is used to displace the gas-containing crude oil in the oil reservoir environment, which can promote the movement of crude oil and increase the yield.

[0058] The inclination simulator 5 is used to control the inclination of the porous medium 8 to simulate the migration of the target gas in the reservoir environment at different inclinations. The purpose is to simulate the actual reservoir exploitation process by injecting the target gas at different angles to perform reservoir exploitation.

[0059] The acquisition module 6 is connected to the inclination simulator 5, and is used to collect the mixture flowing out of the reservoir environment during the migration of the target gas in the porous medium. The mixture includes: water, gas-containing crude oil and gas-free crude oil. The acquisition module can collect the mixture to provide a basis for the changes in data generated when the target gas is injected into the reservoir environment in the later stage.

[0060] The data processing module 7 is used to obtain the migration trajectory of the target gas in the porous medium at different inclination angles based on the content of each component in the mixture, so that the staff can know the migration path of the target gas. Understanding the migration characteristics of the target gas in the reservoir can help optimize the oil recovery strategy. The porous medium is the rock encountered in the process of oil recovery, generally sedimentary rock or igneous rock.

[0061] Through the device provided by the present invention, each medium container is controlled by a high-pressure injection pump to inject different media into the inclination simulator, so that the geological conditions and reservoir structure can be described more accurately, and a more accurate fluid flow simulation can be achieved. During the gas injection development process, the migration law of the target gas can better reflect the complexity and diversity of the real reservoir, thereby improving the accuracy.

[0062] In addition, during the process of injecting the target gas, the inclination angle of the porous medium can be controlled to simulate the gas migration law in the three-dimensional porous medium under different inclination conditions considering the effect of gravity, which is closer to the development law in the real reservoir environment. In this way, the migration trajectory of the target gas obtained can allow the staff to optimize the injection method according to the gas migration law in different reservoir environments in actual applications, control the rate of increase of the production oil-gas ratio, slow down the time of gas channeling, and improve the oil and gas recovery rate.

[0063] In one embodiment, the device also includes: a gas-liquid separation meter, which is connected between the acquisition module and the data processing module; the gas-liquid separation meter is used to perform gas-liquid separation on the mixture, obtain dynamic data of the mixture, and transmit the dynamic data to the data processing module; wherein the dynamic data includes the volume of the water and the volume of the gas-free crude oil; the data processing module is used to calculate the volume of the water and the volume of the gas-free crude oil to obtain the migration trajectory of the target gas in the porous medium at different inclination angles.

[0064] In this embodiment, refer to Figure 1 There is also a gas-liquid separation meter 9 in the inclination reservoir injection gas migration monitoring device. The gas-liquid separation meter 9 is connected between the acquisition module 6 and the data processing module 7. The mixture collected by the acquisition module 6 is subjected to gas-liquid separation to obtain dynamic data of the mixture. The dynamic data refers to the data collected during the migration process. After the dynamic data is obtained, the gas volume and liquid volume in the mixture are measured respectively. The dynamic data includes the volume of water and the volume of crude oil without gas. Then, the dynamic data is processed by the data processing module to obtain the migration trajectory of the target gas in the porous medium at different inclination angles. In addition, the gas front breakthrough time can be analyzed by the gas movement trajectory.

[0065] In one embodiment, the device also includes a control panel, which is respectively connected to the inclination simulator and the acquisition module; the control panel is used to control the temperature and pressure inside the inclination simulator, the inclination of the porous medium, and the sampling time of the acquisition module.

[0066] In this embodiment, combined with Figure 1 The device also includes a control panel 11, which is provided with a temperature control system, a pressure sensing system, a sampling system and an external formation dip simulation system, which can control the temperature and pressure inside the dip simulator 5, the dip of the porous medium 8, and the sampling time of the acquisition module 6, so that the mixture of the same time can be collected at different dips for analysis and comparison.

[0067] In one embodiment, the inclination simulator includes: an upper rubber sleeve and a lower rubber sleeve; wherein the upper rubber sleeve has a protrusion, and the lower rubber sleeve has a groove, the protrusion and the groove are engaged to form a rubber sleeve, and the porous medium is wrapped in the rubber sleeve.

[0068] In this embodiment, refer to Figure 2 and Figure 3 , Figure 2 : is a schematic diagram of the principle of a device for monitoring gas migration injected into an inclined reservoir provided in an embodiment of the present application. Figure 3 is a side view of a rubber sleeve provided in an embodiment of the present application, Figure 2 5 in the figure is the inclination simulator. Figure 3 Exists inside the Tilt Simulator 5, Figure 3 It can be seen that the inclination simulator 5 includes an upper rubber sleeve 501 and a lower rubber sleeve 502. The upper rubber sleeve 501 has a protrusion, and the lower rubber sleeve 502 has a groove that matches the protrusion. The porous medium 8 is placed in the lower rubber sleeve 501. The protrusion and the groove are embedded to form a rubber sleeve, which can wrap the porous medium 8 in the rubber sleeve. During the displacement experiment, the lower rubber sleeve 502 and the upper rubber sleeve 501 can effectively block the fluid backflow corrosion in the porous medium, and can prevent the carbonated water solution formed during the target gas displacement experiment from corroding the core holder, reducing the risk factor during the experiment and improving durability. In addition, Figure 3 12 is a heat-resistant and pressure-resistant steel pipeline, and 508 is a back-pressure valve.

[0069] In one embodiment, the inclination simulator also includes: a clamp and a motor, wherein the clamp is fixedly mounted on the outside of the rubber sleeve; wherein a rotating bearing is installed between the clamp and the motor, wherein one end of the rotating bearing is connected to the output end of the motor, and the other end is connected to the clamp; the motor is used to output power to the rotating bearing so that the rotating bearing rotates the clamp; and the rubber sleeve is used to rotate driven by the clamp to change the inclination angle of the porous medium.

[0070] In this embodiment, combined with Figure 2 , refer to Figure 4 It is a top view of the inside of an inclination simulator provided in an embodiment of the present application. The inclination simulator 5 also includes: a clamp 503 and a motor 504. The clamp is fixedly installed on the outside of the rubber sleeve. A rotating bearing is installed between the clamp 503 and the motor 504. One end of the rotating bearing is connected to the output end of the motor 504, and the other end is connected to the clamp 503; the motor 504 is used to output power to the rotating bearing so that the rotating bearing rotates the clamp; since the clamp is fixedly connected to the rubber sleeve, the rubber sleeve will also rotate driven by the clamp 503 during the rotation of the clamp 503 to change the inclination of the porous medium 8.

[0071] In one embodiment, the inclination simulator includes at least one production outlet, which is connected to the collection module and communicated with the interior of the inclination simulator. The device also includes: a back-pressure pump, which is connected to the inclination simulator; the back-pressure pump is used to control the internal environmental pressure of the inclination simulator so as to drive the mixture in the reservoir environment to flow out of the production outlet under the internal and external pressures of the inclination simulator.

[0072] In this embodiment, combined Figure 1 and Figure 2 The inclination simulator 5 includes at least one production outlet, which is connected to the collection module and communicated with the interior of the inclination simulator 5. The device includes: a back pressure pump 10, which is connected to the back pressure valve inside the inclination simulator 5, and is used to control the internal environmental pressure of the inclination simulator 5, so as to drive the mixture in the reservoir environment to flow out from the production outlet under the internal and external pressures of the inclination simulator 5.

[0073] In one embodiment, the upper rubber sleeve is provided with a plurality of extraction ports, the upper end of the clamp is provided with a sealing cover plate, and the extraction ports are opened on the sealing cover plate; wherein one extraction port corresponds to one extraction port.

[0074] In this embodiment, refer to Figure 5 , Figure 5 is a top view of the exterior of a tilt simulator provided in an embodiment of the present application; Figure 3 and Figure 4 The upper rubber sleeve 501 is provided with a plurality of extraction ports, and the extraction port is a port integrating injection, monitoring and sampling. In this embodiment, 25 extraction ports are provided. There is no limit on the number of extraction ports, which is set according to actual test requirements. A sealing cover plate 505 is provided at the upper end of the clamp 503, and a extraction port 5051 is opened on the sealing plate 505. The extraction port 5051 corresponds one by one to the extraction port (not shown in the figure) of the upper rubber sleeve 501.

[0075] also, Figure 4 5052 is a sealing nut to ensure the safety and accuracy of the equipment during the experiment under high pressure conditions. In this embodiment, 12 sealing nuts are provided, and there is no limit on the number of sealing nuts.

[0076] In addition, refer to Figure 6 , Figure 6 is a front view of the exterior of a tilt simulator provided in an embodiment of the present application; Figure 4 and Figure 5, 506 is a suspension arm, 507 is a turntable, the turntable 507 can be connected to the suspension arm 506 through a transmission shaft, and the suspension arm 506 is also fixedly mounted at both ends of the clamp 503. By rotating the turntable, the height of the suspension arm 506 can be changed, thereby changing the suspension height of the rubber sleeve.

[0077] The following will be combined Figure 2 Here is a detailed description of the use of the device provided by the present invention:

[0078] Assume that the porous medium is a square core and the target gas is carbon dioxide.

[0079] Before the test, the square core is placed in the lower rubber sleeve inside the inclination simulator 5, and then the upper rubber sleeve is engaged with the lower rubber sleeve, and then the upper sealing cover plate of the clamp is connected to the inclination simulator. At this time, the clamp is pressurized to 2MPa through the control panel, and the square core is vacuumed.

[0080] After the preparation work before the experiment is completed, the high-pressure injection pump 1 is controlled to inject high pressure into the water medium container 2, and the water in the water medium container 2 is injected into the square core to saturate the simulated formation water and calculate the pore volume.

[0081] After the simulated formation water is saturated and the void volume is calculated, the high pressure injection into the water medium container 2 is stopped. At the same time, the high pressure injection pump 1 is started to inject high pressure into the crude oil medium container 4. The crude oil medium container 4 injects gas-free crude oil into the square core to drive out the water in the voids of the square core, so that bound water is formed in the voids of the square core. At this time, the crude oil medium container 4 is controlled to inject gas-containing crude oil into the square core until the physical property parameters of the crude oil at the sampling end are consistent with the configured parameters. Saturation is stopped at this time, and the reservoir environment is constructed. In the process of injecting gas-containing crude oil, the control panel 11 sets parameters to control the back pressure valve pressure connected to the back pressure pump 10 to always be higher than the gas-containing crude oil saturation pressure, and the confining pressure is always higher than the injection end pressure by 3MPa. And record the output water volume, calculate the saturated oil volume and oil saturation of the square core. Then set the parameters through the control panel to control the temperature inside the inclination simulator 5 to be constant, and then place the mixture in the constructed reservoir environment in a constant temperature environment for 24 hours for aging treatment to obtain a reservoir environment that is closer to the real reservoir situation.

[0082] Finally, the high-pressure injection pump 1 is started to inject high pressure into the gas medium container 3 to inject carbon dioxide into the square core. At this time, the mixture in the square core is displaced by carbon dioxide, and the displaced mixture passes through the gas-liquid separation meter 9 to record dynamic data, and then calculate relevant parameters. By calculating the values ​​of relevant parameters, the migration trajectory of the carbon dioxide injected into the square core and the front breakthrough time of the carbon dioxide can be analyzed.

[0083] In addition, before injecting carbon dioxide, the inclination of the square core can be changed through the inclination simulator 5, so that the migration trajectory of carbon dioxide at different inclinations can be obtained, which is convenient for later staff to optimize the injection method according to the gas migration law in the oil reservoir environment with different inclinations in actual applications, control the production oil-gas ratio increase rate, slow down the time of gas channeling, and improve the oil and gas recovery rate.

[0084] Embodiment 2

[0085] Reference Figure 7 , Figure 7 The present invention provides a flow chart of the steps of a method for monitoring gas migration in an inclined oil reservoir provided in an embodiment of the present invention; the device for monitoring gas migration in an inclined oil reservoir provided in the present invention comprises: a high-pressure injection pump, a water medium container, a gas medium container, a crude oil medium container, an inclination simulator and a back pressure pump; wherein a porous medium is placed in the inclination simulator; the method steps include:

[0086] Step S701: controlling the water medium container to inject water into the porous medium to simulate formation water saturation.

[0087] In this embodiment, the target gas is carbon dioxide and the porous medium is a square core. First, the square core is placed in the rubber sleeve in the inclination simulator, the upper sealing cover plate of the clamp is connected to the main body, and twelve sealing nuts are tightened. The confining pressure of the core clamp is increased to 2MPa through the control panel and the inclination angle is adjusted. The placed square core is vacuumed, the high-pressure injection pump is started, and the water medium container is connected to inject water into the square core in the inclination simulator. It is saturated with simulated formation water, and relevant data is recorded.

[0088] Step S702: Control the crude oil medium container to inject gas-free crude oil into the porous medium to displace the water so as to form bound water in the internal pores of the porous medium. The produced water volume can be recorded to calculate the saturated oil volume and oil saturation of the core.

[0089] In this embodiment, after step S701 is completed, the high-pressure injection pump is started, and the crude oil medium container is connected to inject gas-free crude oil into the square core to expel the water in the square core and form bound water in the core pores.

[0090] Step S703: controlling the crude oil medium container to inject gas-containing crude oil into the porous medium to construct an oil reservoir environment; wherein the water, the gas-containing crude oil, and the gas-free crude oil flow into the porous medium to form the oil reservoir environment.

[0091] In this embodiment, after step S702 is completed, the high-pressure injection pump is started, and the crude oil medium container is connected to inject gas-containing crude oil into the square core. The gas-containing crude oil is configured according to the high-pressure physical property parameters of the target block, and the injection is stopped until the physical property parameters of the crude oil at the sampling end are consistent with the configured parameters.

[0092] Step S704: controlling the inclination simulator to change the inclination of the porous medium, and simulating the migration trajectory of the target gas in the reservoir environment at different inclinations.

[0093] In this embodiment, after step S703 is completed, the inclination simulator is controlled to change the inclination of the porous medium, and carbon dioxide is injected at different inclinations. The mixture is produced at the production end of the inclination simulator, and the gas volume and liquid volume of the mixture are calculated, thereby intuitively and visually analyzing the migration trajectory of the injected gas.

[0094] In one embodiment, before controlling the inclination simulator to change the inclination of the porous medium to simulate the migration trajectory of the target gas in the reservoir environment at different inclinations, the method further includes: performing an aging treatment on the gas-containing crude oil in the reservoir environment.

[0095] In this embodiment, in order to further simulate the real reservoir environment, the reservoir environment in this embodiment needs to be aged, specifically, placed for 24 hours.

[0096] In one embodiment, before controlling the water medium container to inject water into the porous medium to simulate formation water saturation, the method further includes: vacuuming the porous medium to remove air from the porous medium; and during controlling the crude oil medium container to inject gas-containing crude oil into the porous medium to construct an oil reservoir environment, the method further includes: controlling the pressure of the back pressure pump to be higher than the injection end pressure of the high-pressure injection pump, and the pressure to be higher than the oil saturation pressure of the gas-containing crude oil.

[0097] In this embodiment, before injecting water into the porous medium to simulate formation water saturation, the porous medium needs to be vacuum treated to remove air from the porous medium, thereby avoiding air in the porous medium and improving the accuracy of the experiment.

[0098] In addition, in the process of controlling the construction of the reservoir environment, it is also necessary to control the pressure of the back pressure pump to be higher than the injection end pressure of the high-pressure injection pump to prevent the medium in each container from flowing out from the other end of the inclination simulation device before being injected into the porous medium, and the pressure is higher than the oil saturation pressure of the gas-containing crude oil, specifically the confining pressure. The confining pressure refers to the pressure applied to the formation or reservoir around it. In this embodiment, the confining pressure is always 3MPa higher than the injection end pressure.

[0099] As an example, the calculation process of the migration trajectory of the injected gas is described in detail below:

[0100] Since the matrix of the reservoir is usually non-conductive, the electrical properties of water, crude oil and undissolved gas are very different. The resistivity of crude oil is close to infinity. By adding a certain amount of conductive metal particles, it has a certain conductivity, and the measured data is in the central range. The greater the electrolyte concentration of water in the rock, the smaller the resistance value. Therefore, the dynamic characteristics of gas front migration can be determined based on the changes in the electrical properties of the core.

[0101] First, in step S701, the theoretical method of the relationship between Archie saturation and lithology is used to calibrate the saturation. The saturation index n and the lithology coefficient b in the Archie formula are determined according to formula (1), that is, the water saturation calculation formula:

[0102]

[0103] Among them, Rt is the resistivity of the rock when it contains gas; R0 is the resistivity of the rock when it is completely water-containing; Sw is the water saturation; b is the lithology coefficient; n is the saturation index. There are two general methods for determining the coefficients b and n: the core displacement test method and the empirical coefficient method. For pure sandstone, b = 1 and n = 2 are generally used.

[0104] Based on saturation calibration, an integrated data analysis intelligent system is established. The system uses the material balance method to establish the transport equation, combines the kinetic equation and the physical property change equation in the porous medium to build a mathematical model that considers the gravity factor at different inclination angles, and then uses the finite difference method to discretize the above equations, and obtains the pressure and saturation through implicit pressure and explicit saturation, and then solves and outputs the image.

[0105] In the process of establishing the derivation mathematical model, some conditional assumptions are required to facilitate the solution. The specific assumptions are as follows: consider the existence of gas and liquid two-phase fluid; consider the adsorption and desorption of gas on the rock surface.

[0106] Migration in porous media is mainly affected by capillary force, dispersion force and viscosity force. The component migration equation (2) determines the material balance in the mixture:

[0107]

[0108] Where: C b Indicates the concentration of gas in the liquid phase; C bs It represents the concentration of gas in the attached porous medium under surface conditions; Indicates flow velocity; represents the diffusion tensor; v b represents the reaction rate; φ is the porosity; S wis water saturation, B w is the formation volume coefficient; q w is the injection / production flow rate change; V0 is the total rock volume.

[0109] The first term in the above formula represents the change in gas concentration in the liquid phase, the second term represents the change in the amount of gas adsorption in the porous medium, the first term on the right is the convection phase, the second term is the diffusion phase, the third term is the injection / production phase, and the fourth term is the change phase.

[0110] Flow rate Including the Darcy velocity of the water phase and its own tropism speed Then we have:

[0111]

[0112] It is assumed that the self-tropism velocity The relationship between the concentration and the exponential change is:

[0113]

[0114] Among them, K c is the trend coefficient.

[0115] The dispersion in the liquid phase belongs to the physical dispersion phenomenon. Considering the existence of inclination gravity, molecular diffusion and mechanical dispersion, the total diffusion tensor is determined according to formula (3):

[0116]

[0117] Since the migration in porous media is also mainly affected by capillary force, diffusion force, viscosity force and gravity, and consumption occurs during the migration process, the material balance equation is further determined according to formula (4):

[0118]

[0119] At the same time, carbon dioxide can be adsorbed on the pore surface when it migrates in porous media. According to the material balance equation, the migration equation of formula (4) is corrected by formula (5):

[0120]

[0121] The first term in the above formula represents the change in gas concentration in the liquid phase, the second term represents the change in the amount of gas adsorption in the porous medium, the first term on the right is the convection phase, the second term is the diffusion phase, the third term is the injection / production phase, and the fourth term is the change phase.

[0122] After gas is injected into porous media, some pores are inaccessible to the injected gas due to the gravity effect of the inclination angle. According to formula (6), the porosity in the migration equation at different inclination angles is determined as follows:

[0123] φ=[1-φ(C b ) IPV ]φ0

[0124] Where, φ represents the improved porosity, φ IPV Indicates the inaccessible porosity, φ(C b ) IPV represents the inaccessible porosity, which is related to the concentration C b The related function is obtained by experimental fitting, and φ0 represents the original porosity of the porous medium.

[0125] Since carbon dioxide gas resistance will reduce the permeability of porous media, and the Taylor model is more in line with the actual situation, the model is determined as the permeability equation according to formula (7):

[0126]

[0127] Since the change of residual phase saturation will cause the change of relative permeability, the oil phase permeability is determined according to formula (8), and the water phase permeability is determined according to formula (9):

[0128]

[0129]

[0130] Since dissolved gas will increase the viscosity of the water phase, the change in the viscosity of the water phase can be determined according to formula (10):

[0131] μ pol =μ w +K pol C sp (10)

[0132] Where: μ w C is the viscosity of the water phase without dissolved gas; sp is the concentration of dissolved gas; K pol is a constant.

[0133] In order to facilitate the intelligent solution of mathematical models, a Nx×Ny×Nz grid system is established using deep learning methods, that is, there are Nx grid cells on each row, Ny grid cells on each column, and Nz planes in the vertical direction. The labeling order of the grid blocks in the system is within the row, from one row to another, and from one plane to another.

[0134] The pressure equation is obtained by using the LSOR algorithm, and the component migration equation is solved by using the linear (MOL) method and the third-order Runge-Kutta-Fehlberg (RKF) formula. The displacement pressure is determined by formula (11), the oil saturation is determined by formula (12), the water saturation is determined by formula (13), and the component migration is determined by formula (14):

[0135]

[0136]

[0137]

[0138]

[0139] By changing the inclination of the inclination simulator, the parameters recorded in steps S701 to S704 are substituted into the analysis system including formulas (11) to (14), and the migration trajectory of carbon dioxide can be output. Figure 8 , Fig. 9 and Fig.10 , Figure 8 This is a migration diagram of carbon dioxide at an inclination angle of 50° provided in an embodiment of the present application; Fig. 9 This is a migration diagram of carbon dioxide at an inclination angle of 25° provided in an embodiment of the present application; Fig.10 This is a migration diagram of carbon dioxide at an inclination of 0° provided in an embodiment of the present application. It can be seen that under the same reservoir environment, the migration trajectory of carbon dioxide is different due to the different inclinations of the inclination simulator. The color depth in the figure represents the concentration of carbon dioxide at different depths. Through the change in concentration, the migration trajectory of carbon dioxide can be intuitively seen. After obtaining the migration trajectory of carbon dioxide at different inclinations, the staff can choose the most suitable inclination to inject carbon dioxide into the real reservoir environment for oil recovery and exploitation.

[0140] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0141] The embodiments of the present invention are described with reference to the flowcharts and / or block diagrams of the apparatus according to the embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0142] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0143] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, device, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, device, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a..." do not exclude the existence of other identical elements in the process, device, article or terminal device including the elements.

[0144] The above is a detailed introduction to the device and method for monitoring the migration of gas injected into an inclined oil reservoir provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the device of the present invention and its core idea; at the same time, for general technicians in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A device for monitoring gas migration in an inclined oil reservoir, characterized in that: The device comprises: a high-pressure injection pump, a water medium container, a gas medium container, a crude oil medium container, a dip simulator, a collection module and a data processing module; wherein a porous medium is placed in the dip simulator; The high-pressure injection pump is connected to the inlet valves of the water medium container, the gas medium container and the crude oil medium container respectively, and the outlet valves of the water medium container, the gas medium container and the crude oil medium container are connected to the inclination simulator respectively; The high-pressure injection pump is used to control the water medium container to introduce water into the inclination simulator, the crude oil medium container to introduce gas-containing crude oil and gas-free crude oil into the inclination simulator, and to control the gas medium container to introduce target gas into the inclination simulator; wherein the water, the gas-containing crude oil, and the gas-free crude oil flow into the porous medium to form an oil reservoir environment, and the target gas is used to displace the gas-containing crude oil in the oil reservoir environment; The inclination simulator is used to control the inclination of the porous medium to simulate the migration of the target gas in the reservoir environment at different inclinations; The acquisition module is connected to the inclination simulator and is used to collect a mixture of the target gas flowing out of the reservoir environment during the migration of the porous medium, wherein the mixture includes: the water, the gas-containing crude oil and the gas-free crude oil; The data processing module is used to obtain the migration trajectory of the target gas in the porous medium at different inclination angles based on the mixture.

2. The device according to claim 1, characterized in that The device further comprises: a gas-liquid separation meter connected between the acquisition module and the data processing module; The gas-liquid separation meter is used to perform gas-liquid separation on the mixture, obtain dynamic data of the mixture, and transmit the dynamic data to the data processing module; wherein the dynamic data includes the volume of the water and the volume of the gas-free crude oil; The data processing module is used to calculate the volume of the water and the volume of the gas-free crude oil to obtain the migration trajectory of the target gas in the porous medium at different inclination angles.

3. The device according to claim 2, characterized in that The device also includes a control panel, which is connected to the inclination simulator and the acquisition module respectively; The control panel is used to control the temperature and pressure inside the inclination simulator, the inclination of the porous medium, and the sampling time of the acquisition module.

4. The device according to claim 1, characterized in that The tilt simulator comprises: an upper rubber sleeve and a lower rubber sleeve; Among them, the upper rubber sleeve has a protrusion, the lower rubber sleeve has a groove, the protrusion and the groove are embedded in each other to form a rubber sleeve, and the porous medium is wrapped in the rubber sleeve.

5. The device according to claim 4, characterized in that The tilt simulator further comprises: a clamp and a motor, wherein the clamp is fixedly mounted on the outside of the rubber sleeve; wherein a rotating bearing is mounted between the clamp and the motor, wherein one end of the rotating bearing is connected to the output end of the motor, and the other end is connected to the clamp; The motor is used to output power to the rotating bearing so that the rotating bearing rotates the clamp; The rubber sleeve is used to rotate under the drive of the clamp to change the inclination angle of the porous medium.

6. The device according to claim 5, characterized in that The inclination simulator comprises at least one production outlet, the production outlet is connected to the collection module and communicated with the interior of the inclination simulator, and the device further comprises: a back pressure pump, the back pressure pump is connected to the inclination simulator; The back-pressure pump is used to control the internal environmental pressure of the inclination simulator, so as to drive the mixture in the reservoir environment to flow out from the production port under the internal and external pressures of the inclination simulator.

7. The device according to claim 6, characterized in that The upper rubber sleeve is provided with a plurality of extraction ports, the upper end of the clamp is provided with a sealing cover plate, and the extraction ports are opened on the sealing cover plate; wherein one extraction port corresponds to one extraction port.

8. A method for monitoring the migration of injected gas in an inclined oil reservoir, characterized in that: The device for monitoring migration of injected gas in an inclined oil reservoir as claimed in any one of claims 1 to 7 comprises: a high-pressure injection pump, a water medium container, a gas medium container, a crude oil medium container, an inclination simulator and a back pressure pump; wherein a porous medium is placed in the inclination simulator; and the method comprises: Controlling the water medium container to inject water into the porous medium to simulate formation water saturation; Controlling the crude oil medium container to inject gas-free crude oil into the porous medium to displace the water, so as to form bound water in the internal pores of the porous medium; Controlling the crude oil medium container to inject gas-containing crude oil into the porous medium to construct an oil reservoir environment; wherein the water, the gas-containing crude oil, and the gas-free crude oil flow into the porous medium to form the oil reservoir environment; The inclination simulator is controlled to change the inclination of the porous medium, so as to simulate the migration trajectory of the target gas in the reservoir environment at different inclinations.

9. The method according to claim 8, characterized in that Before the inclination simulator is controlled to change the inclination of the porous medium to simulate the migration trajectory of the target gas in the reservoir environment at different inclinations, the method further includes: An aging treatment is performed on the gas-bearing crude oil in the oil reservoir environment.

10. The method according to claim 8, characterized in that Before controlling the water medium container to inject water into the porous medium to simulate formation water saturation, the method further includes: Performing vacuum treatment on the porous medium to remove air from the porous medium; In the process of controlling the crude oil medium container to inject gas-containing crude oil into the porous medium to construct the reservoir environment, the method further includes: The pressure of the back pressure pump is controlled to be higher than the injection end pressure of the high pressure injection pump, and the pressure is controlled to be higher than the oil saturation pressure of the gas-containing crude oil.

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