Online analysis experiment system for simulating fluid migration and component change under multi-scene multi-medium multi-field coupling

Abstract

The invention discloses an online analysis experiment system for simulating fluid migration and component change under multi-scene multi-medium multi-field coupling, which comprises a model unit and a fluid conveying unit, and the fluid conveying unit injects experiment fluid into the model unit. Each model unit structurally comprises a cylindrical shell with two open ends, a rubber cylinder is arranged in the shell, an annular space between the rubber cylinder and the shell is sealed, experimental fluid can be directly injected into the rubber cylinder, or experimental fluid can be injected into the rubber cylinder after a rock core or a sand filling model is placed, and a plurality of monitoring holes are formed in the side wall of the rubber cylinder at equal intervals. The sampling holes are communicated with the corresponding round pipes on the shell to serve as monitoring channels or sampling holes, and sealing covers or monitoring sensors are selectively installed on the monitoring channels. The experiment system can test and analyze fluid mixing and mixing zone change, displacement migration, component change and other conditions under multi-scene multi-medium multi-field coupling on line, for example, the experiment system is used for oil and gas displacement, gas storage injection and production simulation, underground energy storage and other experiment researches.

Description

Technical Field

[0001] This invention relates to the field of oil and gas reservoir development technology, and in particular to an online experimental system for simulating fluid transport and composition changes under multi-scenario, multi-media, and multi-field coupling. Background Technology

[0002] Indoor seepage experiments serve as a crucial bridge connecting the microscopic characteristics of underground reservoirs with the macroscopic development dynamics, providing intuitive and precise theoretical guidance for clarifying reservoir fluid seepage patterns and optimizing reservoir development effects. Current seepage experiments can be broadly categorized into: traditional oil and gas reservoir development evaluation experiments primarily focused on obtaining single-phase or multi-phase flow characteristics of oil, gas, and water; enhanced oil recovery mechanism experiments centered on multi-phase fluid displacement; and underground gas storage simulation experiments primarily involving multi-cycle injection and production and gas mixing. While all these experiments fall under the category of seepage, their core experimental data focus, required experimental conditions (pressure, temperature, fluid system, measurement accuracy), and process design differ significantly. However, current seepage experimental setups, primarily based on conventional core holders and three-dimensional sand-filled models, can typically only be optimized to accurately realize one of the aforementioned experimental scenarios, resulting in limited equipment functionality. For example, an experimental system primarily designed for displacement may be functionally incompatible with experimental studies of fluid component distribution characteristics, and may also fail to meet the scale requirements of gas storage simulation experiments. The current state of these devices, with their simple structure and limited system functions, makes it impossible to construct a rigorous experimental environment when addressing complex reservoirs or cross-disciplinary research needs. This hinders a deeper understanding and integrated research of the multi-physics coupled seepage mechanism. Therefore, developing seepage experimental devices that are compatible with various experimental scenarios and possess greater adaptability and integration capabilities has become an important direction for promoting the development of seepage experimental technology and addressing the needs of complex energy development. Summary of the Invention

[0003] To address the aforementioned problems with existing experimental devices, this invention provides an online experimental system for simulating fluid transport and composition changes under multi-scenario, multi-medium, and multi-field coupling.

[0004] The present invention provides an online experimental system for simulating fluid transport and composition changes under multi-scenario, multi-media, and multi-field coupling, comprising a model unit and a fluid delivery unit; the model unit is placed in a constant temperature chamber, and the fluid delivery unit injects experimental fluid into the model unit. The experimental fluid is either a gas or a liquid.

[0005] The model unit includes a cylindrical shell open at both ends. Inside the shell, a rubber tube open at both ends is disposed. The outer diameter of the rubber tube is smaller than the inner diameter of the shell. The two ends of the rubber tube are sealed to the inner walls of the shell at both ends, sealing the annular space between the rubber tube and the shell. Sealing plugs are provided at both ends of the shell. The sealing plugs have fluid inlets and outlets for injecting experimental fluid into the rubber tube. Several monitoring holes are evenly spaced on the side wall of the rubber tube, communicating with the internal space of the rubber tube. A circular tube is fixedly installed on each monitoring hole, extending to the outside of the shell as a monitoring channel. A sealing cap or a monitoring sensor can be selectively installed on the monitoring channel located outside the shell. The monitoring sensor can be a sensor for monitoring parameters such as gas composition, water saturation, and pressure. For example, it can be a gas chromatograph sensor for monitoring changes in gas composition, connected to an external gas chromatograph. Preferably, several monitoring channels are symmetrically distributed on both opposite sides of the shell wall.

[0006] The inside of the rubber tube can be used as an intermediate container to directly inject experimental fluids for conducting single-phase or multi-phase dispersion convection experiments between different gases and liquids, such as gas solubility testing and mixed gas preparation.

[0007] The rubber tube can also hold a rock core or be filled with sand as a sand-filled model. In this case, a confining pressure port needs to be provided on the side wall of the shell. The annular sealing space between the rubber tube and the shell is connected to the confining pressure port, which is connected to a confining pressure pump. The annular space between the rubber tube and the shell is used to apply confining pressure to the rock core or sand-filled model.

[0008] The sealing cover includes a plunger A, a sealing ring A, and a cap A. The plunger A consists of two cylindrical sections with different diameters. The diameter of the lower cylindrical section is equal to the inner diameter of the monitoring channel, and the diameter of the upper cylindrical section is greater than the outer diameter of the monitoring channel. After the sealing ring A is fitted onto the lower cylindrical section, the lower cylindrical section is inserted into the monitoring channel, while the upper cylindrical section is located outside the monitoring channel. The cap A is then fitted onto the upper cylindrical section, and the cap A is connected to the outer wall of the monitoring channel via threads to seal and fix the plunger A.

[0009] The installation method of the monitoring sensor is as follows: A plunger B is installed on the monitoring channel. The plunger B consists of two cylindrical sections with different diameters. The diameter of the lower cylindrical section is equal to the inner diameter of the monitoring channel, and the diameter of the upper cylindrical section is greater than the outer diameter of the monitoring channel. After fitting a sealing ring B on the lower cylindrical section, the lower cylindrical section is inserted into the monitoring channel, while the upper cylindrical section is located outside the monitoring channel. The cap B is fitted onto the upper cylindrical section and screwed into the threaded connection on the outer wall of the monitoring channel to seal and fix the plunger B. A through hole for inserting the monitoring sensor is opened at the center of both the plunger B and the cap B. The front end of the monitoring sensor is inserted into the interior of the rubber tube.

[0010] The sealing plug includes a plunger C and a cap C. One end of the plunger C is inserted into the ports at both ends of the housing. The inner wall of the cap C is threaded, and the outer side of the ports at both ends of the housing is also threaded. The cap C19 is fitted onto the plunger C18 and threadedly connected to the housing to achieve a fixed seal. Both the cap C and the plunger C have through holes at their center positions as fluid inlets and outlets.

[0011] The fluid delivery unit includes a fluid storage tank, an intermediate container, a displacement pump, and a vacuum pump. The fluid storage tank is connected to the intermediate container via a pipeline. Branch pipelines A and B are installed on the pipeline connecting the fluid storage tank and the intermediate container. Branch pipeline A is connected to the vacuum pump, and branch pipeline B is connected to the fluid inlet at one end of the model unit. Valves are installed between the branch point of the fluid storage tank and branch pipeline A, between the branch point of branch pipeline B and the intermediate container, and on both branch pipeline A and branch pipeline B. The displacement pump is connected to the bottom of the intermediate container.

[0012] Compared with the prior art, the advantages of the present invention are: (1) The experimental system of the present invention provides a fluid transport and component analysis device suitable for multiple media. The model unit is compatible with both real rock cores and artificial sand-filled models as experimental carriers, and can also be used directly as an intermediate container for single-phase or multi-phase dispersion convection experiments between different gases and liquids, such as gas solubility testing and mixed gas preparation. It is a multifunctional experimental device compatible with multiple experimental scenarios.

[0013] (2) The model unit used in this invention provides a flexible analysis and testing method, which can perform multi-point sampling analysis and online analysis to meet various experimental analysis and testing needs.

[0014] (3) The model unit of the present invention has non-destructive online testing capabilities. During the experiment, no fluid samples need to be extracted from the experimental medium (core, sand-filled model). Fluid information at different locations in the medium can be obtained in real time and in situ, fundamentally eliminating sample loss and pressure fluctuations caused by sampling, and greatly improving the accuracy of experimental results. In addition, by connecting different external testing systems, various physical parameters, such as water saturation, resistivity, gas composition, pressure distribution and other fluid information, can be obtained to realize experimental data under multi-field coupling.

[0015] (4) The experimental system of the present invention is suitable for online testing and analysis of fluid mixing and mixing zone changes, displacement and migration and component changes under multi-scenario, multi-medium and multi-field coupling, such as oil reservoirs, gas reservoirs, multiphase fluid displacement, gas storage injection and production simulation and underground energy storage, etc., which rely on the analysis of gas phase components inside the model.

[0016] (5) The sampling and monitoring design of this invention reduces the complexity of the experiment and the operational risk, reduces the operation steps of frequently disassembling and assembling pipelines in traditional experiments, and reduces the risk of leakage in high-pressure experiments; at the same time, the in-situ monitoring function reduces the operational error of human sampling.

[0017] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the experimental system for online analysis of fluid transport and composition changes under multi-scenario, multi-medium, and multi-field coupling, as described in this invention.

[0019] Figure 2 This is a schematic diagram of the model unit structure.

[0020] Figure 3 This is a cross-sectional view of the model element.

[0021] Figure 4 This is a schematic diagram of the rubber tube structure.

[0022] Figure 5 This is a schematic diagram of the sealing cap.

[0023] Figure 6 This is a schematic diagram of the installation structure of a gas chromatography sensor.

[0024] Figure 7 This is a schematic diagram of the structure of the cap C.

[0025] Numbering on the map: 1-Shell, 2-Rubber tube, 3-Sealing plug, 4-Pressure port, 5-Core, 6-Monitoring channel, 7-Sealing cap, 8-Gas chromatograph sensor, 9-Gas chromatograph, 10-Plunger A, 11-Sealing ring A, 12-Cap A, 13-Plunger B, 14-Sealing ring B, 15-Cap B, 16-Protrusion, 17-Sealing ring C, 18-Plunger C, 19-Cap C, 20-Gas inlet / outlet, 21-Thread, 22-Thread, 23-Model unit, 24-Constant temperature chamber, 25-Pressure pump, 26-Gas storage tank, 27-Intermediate container, 28-Displacement pump, 29-Vacuum pump, 30-Valve, 31-Valve, 32-Valve, 33-Valve, 34-Valve, 35-Thread. Detailed Implementation

[0026] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0027] In this embodiment, the online analysis experimental system for fluid transport and composition changes under simulated multi-scenario, multi-media, and multi-field coupling of the present invention is used to obtain the internal gas composition changes of real reservoir cores online. For example... Figure 1-7 As shown, the experimental system includes a model unit 23 and a fluid delivery unit (specifically a gas delivery unit in this embodiment). The model unit 23 is placed inside a constant temperature chamber 24. The gas delivery unit includes a gas storage tank 26, an intermediate container 27, a displacement pump 28, and a vacuum pump 29. The gas storage tank 26 is connected to the intermediate container 27 via a pipeline. Branch pipelines A and B are installed on the pipeline connecting the gas storage tank 26 and the intermediate container 27. Branch pipeline A is connected to the vacuum pump 29, and branch pipeline B is connected to the air inlet at one end of the model unit 23. A valve 30 is installed between the gas storage tank 26 and the branch point of branch pipeline A. Valves 31 and 32 are installed on branch pipeline A and branch pipeline B, respectively. A valve 33 is installed between the branch point of branch pipeline B and the intermediate container 27. A valve 34 and the displacement pump 28 are connected to the bottom of the intermediate container.

[0028] The model unit 23 comprises a cylindrical shell 1 open at both ends, with a rubber tube 2 also open at both ends inside the shell. The outer diameter of the rubber tube 2 is smaller than the inner diameter of the shell 1. The two ends of the rubber tube 2 are sealed to the inner walls of the shell 1, sealing the annular space between the rubber tube and the shell. Sealing plugs 3 are provided at both ends of the shell. A confining pressure port 4 is provided on the side wall of the shell, communicating with the annular space between the rubber tube 2 and the shell 1. The confining pressure port 4 is connected to a confining pressure pump 25. The interior of the rubber tube 2 is used to hold the core 5. Several monitoring holes are evenly spaced on the side wall of the rubber tube 2, communicating with the interior space of the rubber tube 2. A circular hole is also provided on the shell 1 opposite to the monitoring hole. A cylinder is fixedly installed on the monitoring hole, extending through the circular hole of the shell to the outside of the shell to form a monitoring channel 6. The contact point between the cylinder and the circular hole of the shell is sealed. A sealing cap 7 or a gas chromatograph sensor 8 can be selectively installed on the monitoring channel located outside the shell. The gas chromatograph sensor 8 is connected to an external gas chromatograph 9. In one specific embodiment, a pressure port 4 is provided at each end of the side wall of the housing 1. Nine equally spaced monitoring channels are provided on the two opposite surfaces of the side wall of the housing between the two pressure ports 4, for a total of 18 monitoring channels. Some or all of these monitoring channels can be selectively used to install gas chromatograph sensors 9 according to experimental needs. Unused monitoring channels are sealed with sealing caps 7.

[0029] The sealing cap 7 includes a plunger A10, a sealing ring A11, and a cap A12. The plunger A10 consists of two cylindrical sections with different diameters. The diameter of the lower cylindrical section is equal to the inner diameter of the monitoring channel, and the diameter of the upper cylindrical section is larger than the outer diameter of the monitoring channel. After the sealing ring A11 is fitted onto the lower cylindrical section, the lower cylindrical section is inserted into the monitoring channel 6, with the upper cylindrical section located outside the monitoring channel 6. The cap A12 is fitted onto the upper cylindrical section. The inner wall of the cap A12 is threaded with threads 21, which connect to the outer wall of the monitoring channel 6 to seal and fix the plunger A10. In one specific embodiment, the cap A12 has a central opening at its top.

[0030] The gas chromatograph sensor 8 is installed as follows: a plunger B13 is installed on the monitoring channel. The plunger B13 consists of two cylindrical sections with different diameters. The diameter of the lower cylindrical section is equal to the inner diameter of the monitoring channel 6, and the diameter of the upper cylindrical section is larger than the outer diameter of the monitoring channel 6. After fitting a sealing ring B14 onto the lower cylindrical section, the lower cylindrical section is inserted into the monitoring channel 6, while the upper cylindrical section is located outside the monitoring channel 6. The inner wall of the cap B15 is threaded with threads 22. The cap B15 is fitted onto the upper cylindrical section and tightened to seal the plunger B13. Both the plunger B13 and the cap B15 have through holes at their centers for inserting the gas chromatograph sensor 8. The gas chromatograph sensor 8 is inserted into the rubber sleeve 2. In one specific embodiment, a cylindrical protrusion 16 is provided at the center of the top of the plunger B13, and the cap B15 has a center opening at its top. The protrusion 16 passes through the center hole of the cap B15 and is located outside the cap B15. A through hole is also provided in the center of the protrusion 16. The gas chromatograph sensor 8 is inserted through the through hole in the center of the protrusion 16 and extends into the rubber sleeve 2. A sealing ring C17 is installed at the contact point between the gas chromatograph sensor 8 and the top surface of the protrusion 16.

[0031] The sealing plugs 3 on both sides of the model unit include plungers C18 and caps C19. One end of the plunger C18 is inserted into the ports at both ends of the housing 1. The inner wall of the cap C19 is threaded, and the outer side of the ports at both ends of the housing is also threaded. The cap C19 is fitted onto the plunger C18 and threadedly connected to the housing to achieve a fixed seal. Both the cap C19 and the plunger C18 have through holes at their centers as gas inlets and outlets 20. In one specific embodiment, the cap C19 consists of two cylindrical sections of different diameters, both with threads 35 on their inner walls. Both ends of the plunger C18 have external threads; one end is inserted into the housing and engages with the threads on the inner wall of the housing to achieve a threaded connection. The cap C19 is fitted onto the plunger C18 located outside the housing. The larger diameter cylinder of the cap C19 is fitted onto the housing and threadedly connected to the housing's external threads, while the smaller diameter cylinder is fitted onto the threaded section of the plunger C18 to form a threaded connection. A central through-hole is formed in the center of plunger C18, which serves as a gas inlet / outlet and connects to the interior of the rubber sleeve. Depending on the needs of the actual experiment, one of the central through-holes of plunger C18 at both ends of the shell can be used as an air inlet and the other as an air outlet, or only one central through-hole can be used as an air inlet while the other central through-hole is sealed.

[0032] The specific experimental testing methods are as follows: (1) Cut the long rock core into standard size, with a diameter of 38mm and a length of 1000mm. Then, put the long rock core into the rubber tube 2 of the model unit to ensure that the long rock core is well sealed.

[0033] (2) Install the sealing plug 3, sealing cover 7 and gas chromatograph sensor 8 on the model unit. The gas chromatograph sensor 8 is used to monitor the changes in gas composition along the core length in real time. Place the model unit 23 in a constant temperature chamber 24 with adjustable temperature. Use vacuum pump 29 to evacuate the model unit and connected pipelines to remove air and ensure the system is airtight.

[0034] (3) Close valves 31, 32 and 34, open valves 30 and 33, and inject the experimental gas from the gas storage tank 26 into the intermediate container 27.

[0035] (4) Close valves 30 and 31, and open valves 32, 33, and 34. Use displacement pump 28 to inject the gas from intermediate container 27 into model unit 23 according to experimental requirements. Subsequently, perform gas-driven or mixed-gas-driven experiments according to the experimental plan. If a mixed-gas-driven experiment is performed, different gas storage tanks 26 are needed to store different gases, and different intermediate containers 27 are also required. Gas composition information at corresponding measurement points is collected in real time using gas chromatograph sensor 8 and gas chromatograph 9. After the experiment, shut off the gas source, release the pressure, remove the core sample, and clean and purify the equipment.

[0036] The above embodiments are merely specific application examples of the experimental system of the present invention and are not intended to limit the present invention in any way. Besides gases, the experimental system of the present invention is also suitable for liquids as experimental fluids. The model unit can be used for both core samples and artificial sand-filled models as experimental carriers. Therefore, the experimental system of the present invention can be used for gas or liquid displacement experiments, gas mixing in gas storage facilities, gas injection and production simulations in gas storage facilities, etc., that is, to realize online analysis and simulation experiments of fluid transport and component changes under multi-scenario, multi-media, and multi-field coupling.

Claims

1. An online experimental system for simulating fluid transport and composition changes under multi-scenario, multi-medium, and multi-field coupling, characterized in that, It includes a model unit and a fluid delivery unit. The model unit is placed in a constant temperature chamber, and the fluid delivery unit injects experimental fluid into the model unit. The structure of the model unit includes a cylindrical shell with openings at both ends. Inside the shell, there is a rubber tube with openings at both ends. The outer diameter of the rubber tube is smaller than the inner diameter of the shell. The two ends of the rubber tube are respectively sealed to the inner walls of the two ends of the shell to seal the annular space between the rubber tube and the shell. The two ends of the shell are provided with sealing plugs, and the sealing plugs are provided with fluid inlets and outlets for injecting experimental fluid into the rubber tube. Several monitoring holes are evenly spaced on the side wall of the rubber tube. The monitoring holes are connected to the internal space of the rubber tube. A round tube is fixedly installed on the monitoring hole and extends to the outside of the shell as a monitoring channel. A sealing cover or a monitoring sensor can be selectively installed on the monitoring channel located outside the shell. The experimental fluid is either a gas or a liquid; The monitoring sensor is used for online monitoring of any parameter, including changes in gas composition, water saturation, resistivity, and pressure distribution.

2. The online analysis experimental system for simulating fluid transport and composition changes under multi-scenario, multi-medium, and multi-field coupling as described in claim 1, characterized in that, The sealing cover includes a plunger A, a sealing ring A, and a cap A. The plunger A consists of two cylindrical sections with different diameters. The diameter of the lower cylindrical section is equal to the inner diameter of the monitoring channel, and the diameter of the upper cylindrical section is greater than the outer diameter of the monitoring channel. After the sealing ring A is fitted onto the lower cylindrical section, the lower cylindrical section is inserted into the monitoring channel, while the upper cylindrical section is located outside the monitoring channel. The cap A is fitted onto the upper cylindrical section, and the cap A is connected to the outer wall of the monitoring channel by threads to seal and fix the plunger A.

3. The online analysis experimental system for simulating fluid transport and composition changes under multi-scenario, multi-medium, and multi-field coupling as described in claim 1, characterized in that, The installation method of the monitoring sensor is as follows: A plunger B is installed on the monitoring channel. The plunger B consists of two cylindrical sections with different diameters. The diameter of the lower cylindrical section is equal to the inner diameter of the monitoring channel, and the diameter of the upper cylindrical section is greater than the outer diameter of the monitoring channel. After fitting a sealing ring B on the lower cylindrical section, the lower cylindrical section is inserted into the monitoring channel, while the upper cylindrical section is located outside the monitoring channel. A cap B is fitted onto the upper cylindrical section and screwed into the threaded connection on the outer wall of the monitoring channel to seal and fix the plunger B. A through hole for inserting the monitoring sensor is opened at the center of both the plunger B and the cap B. The front end of the monitoring sensor is inserted into the interior of the rubber tube.

4. The online analysis experimental system for simulating fluid transport and composition changes under multi-scenario, multi-medium, and multi-field coupling as described in claim 1, characterized in that, The sealing plug includes a plunger C and a cap C. One end of the plunger C is inserted into the ports at both ends of the housing. The inner wall of the cap C is threaded, and the outer side of the ports at both ends of the housing is also threaded. The cap C19 is fitted onto the plunger C18 and threadedly connected to the housing to achieve a fixed seal. A through hole is opened at the center of both the cap C and the plunger C as a fluid inlet and outlet.

5. The online analysis experimental system for simulating fluid transport and composition changes under multi-scenario, multi-medium, and multi-field coupling as described in claim 1, characterized in that, The inside of the rubber tube can be selectively filled with rock cores or sand as a sand-filled model.

6. The online analysis experimental system for simulating fluid transport and composition changes under multi-scenario, multi-medium, and multi-field coupling as described in claim 5, characterized in that, The side wall of the housing is provided with a confining pressure port, and the annular sealing space between the rubber tube and the housing is connected to the confining pressure port, which is connected to a confining pressure pump.

7. The online analysis experimental system for simulating fluid transport and composition changes under multi-scenario, multi-medium, and multi-field coupling as described in claim 1, characterized in that, A number of monitoring channels are symmetrically distributed on both sides of the shell wall.

8. The online analysis experimental system for simulating fluid transport and composition changes under multi-scenario, multi-medium, and multi-field coupling as described in claim 1, characterized in that, The fluid delivery unit includes a fluid storage tank, an intermediate container, a displacement pump, and a vacuum pump. The fluid storage tank is connected to the intermediate container via a pipeline. Branch pipelines A and B are installed on the pipeline connecting the fluid storage tank and the intermediate container. Branch pipeline A is connected to the vacuum pump, and branch pipeline B is connected to the fluid inlet at one end of the model unit. Valves are installed between the branch point of the fluid storage tank and branch pipeline A, between the branch point of branch pipeline B and the intermediate container, and on both branch pipeline A and branch pipeline B. The displacement pump is connected to the bottom of the intermediate container.

Images