A simulation device suitable for gas geological storage

Abstract

The present invention relates to the technical field of supergravity physical simulation experimental equipment for geotechnical engineering and energy engineering, and discloses a simulation device suitable for gas geological storage; it is applied to the simulation of CO2 storage in saline aquifers, including: a reaction kettle, an environmental parameter control module, a liquid injection module, a gas injection module and a data acquisition module; the simulation device suitable for gas geological storage can real-time control the environmental parameters of the geology through the environmental parameter control module to ensure that the variables are controllable during the simulation process and ensure the accuracy of the simulation experiment. At the same time, through the data acquisition module, the parameter changes of the saline aquifer during the gas storage process are monitored in real time, so as to obtain accurate simulation experiment parameters.

Description

Technical Field

[0001] The invention relates to the technical field of hypergravity physics simulation experimental equipment for geotechnical engineering and energy engineering, and in particular to a simulation device suitable for geological storage of gas. Background Art

[0002] The global climate change problem is becoming increasingly serious. Reducing greenhouse gas emissions to mitigate climate change has become a hot topic of concern in the international community today. Among the many greenhouse gas emission reduction technology solutions, carbon capture, utilization and storage technology is an emerging technology that can achieve large-scale low-carbon utilization of fossil energy. It is one of the important technical options for mitigating CO2 emissions in the future.

[0003] To date, several types of geological structures for CO2 storage have been identified, including saline aquifers, unmineable coal seams, and depleted oil or hydrocarbon reservoirs. Deep saline aquifers are considered to be the main potential areas for future CO2 geological storage due to their widespread distribution and large reserves.

[0004] In the CO2 storage process, CO2 from anthropogenic sources is injected into deep saline aquifers through injection wells and stored in the aquifers through several capture mechanisms that ensure the long-term stability of the storage process. These mechanisms include stratigraphic and tectonic capture, capillary or residual capture, mineral dissolution and hydrodynamic capture. Among them, capillary or residual capture is widely considered to be the fastest and largest capture mode. The residual capture process starts within a short period of CO2 injection (days to months) and continues to make a significant contribution to the long-term capture process over the following decades. Drainage is achieved by injecting CO2 into the saline reservoir rock mass until the irreducible water saturation and maximum CO2 saturation are reached. Once the saline water reaches the irreducible water saturation state, the imbibition cycle begins and the saline water is reinjected in the rock until the relative permeability of CO2 reaches zero.

[0005] However, the potential irreducible water saturation conditions in the rock pore space of saline aquifers provide less space for CO2 storage, so there is always a greater saturation of captured CO2 in saline aquifers at lower irreducible water saturation (Swirr). The CO2 storage efficiency (Epore) can be defined as the ratio of the injected CO2 volume to the pore space volume of the saline aquifer rock, which means that Epore and Swirr are closely related, and the CO2 storage efficiency / capacity increases with decreasing irreducible water saturation and increases with decreasing residual water saturation of the formation. Therefore, it is crucial to understand the formation of residual water during drainage and the factors that affect its effective storage of CO2 in saline aquifers.

[0006] Therefore, in order to ensure the scientificity and effectiveness of the indoor carbon dioxide storage model experiment, the first thing to be solved is the accurate control of the physical environment and boundary conditions of the saline aquifer reservoir model. Among them, the gravity field, pressure field, and temperature field are three key factors that affect the multi-phase and multi-field interaction process of long-term CO2 injection in the in-situ large-scale saline aquifer reservoir. On the basis of restoring the large-scale reservoir stress gradient, effectively maintaining the reservoir overburden pressure and reproducing the reservoir gradient temperature environment are still the bottleneck problems of the current CO2 saline aquifer storage simulation device. Summary of the invention

[0007] In view of this, the present invention provides a simulation device suitable for gas geological storage to overcome the problems in the prior art of simulating the long-duration injection process of carbon dioxide saline layer storage, which is difficult and the simulation process variable control is complex.

[0008] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0009] In the first aspect, the present invention provides a simulation device suitable for gas geological storage, which is applied to the storage simulation of CO2 in saline water layers, comprising: a reactor, an environmental parameter control module, a liquid injection module, a gas injection module and a data acquisition module; a filling cavity is provided inside the reactor, and a filler is provided in the filling cavity to simulate the saline water layer; the environmental parameter control module is arranged in the reactor to control the environmental parameters of the filling cavity to simulate the environment of the saline water layer; the liquid injection module and the gas injection module are both connected to the filling cavity to introduce liquid and gaseous CO2 into the filling cavity; the data acquisition module is arranged in the filling cavity and located in the filler, and the data acquisition module is suitable for detecting changes in temperature parameters, pressure parameters and resistivity parameters of the filler after the CO2 is injected into the filling cavity.

[0010] The invention has the following advantages: the filler is arranged in the filling cavity, and the environmental parameters of the filling cavity are controlled by the environmental parameter control module, so as to simulate the environmental parameters of the saline layer; the liquid injection module is connected with the filling cavity to inject liquid into the filling cavity to form saline water; after setting the environmental parameters of the saline layer and injecting the liquid, the gas injection module is connected with the filling cavity, and CO2 is injected into the filling cavity to discharge the saline water, so as to realize the sealing of CO2; in this process, the changes of temperature parameters, pressure parameters and resistivity parameters in the gas sealing process are monitored by the data acquisition module, so as to obtain the simulation experiment parameters. The simulation device suitable for geological gas sealing controls the geological environmental parameters in real time through the environmental parameter control module, so as to ensure that the variables are controllable in the simulation process, so as to ensure the accuracy of the simulation experiment. At the same time, the parameter changes of the saline layer in the gas sealing process are monitored in real time through the data acquisition module, so as to obtain accurate simulation experiment parameters.

[0011] In an embodiment of the first aspect of the present invention, the environmental parameters include temperature parameters and pressure parameters, and the environmental parameter control module includes a servo temperature control module and a pressure control module. The servo temperature control module is suitable for controlling the temperature parameters of the filler to simulate the environmental temperature of the saltwater layer; the pressure control module is suitable for controlling the pressure parameters of the filling cavity to simulate the environmental pressure of the saltwater layer.

[0012] In the first aspect of the embodiment of the present invention, the reaction kettle includes a kettle base, a kettle body and a kettle cover which are separately arranged, and the two ends of the kettle body are fixedly connected to the kettle base and the kettle cover by fasteners to enclose and form a filling cavity, and the data acquisition module is passed through the kettle base and partially extends into the filling cavity.

[0013] In an embodiment of the first aspect of the present invention, the servo temperature control module includes a temperature controller and a heating component, the heating component is arranged on the periphery of the kettle body and / or in the filling cavity, and the temperature controller controls the heating of the heating component to simulate the ambient temperature of the saltwater layer.

[0014] In an embodiment of the first aspect of the present invention, the heating assembly is a heating jacket and / or a heating plate, the heating jacket is arranged on the outer periphery of the kettle body, the heating plate is arranged at the bottom of the filling cavity, and the heating jacket and the heating plate are communicatively connected to the temperature controller.

[0015] In an embodiment of the first aspect of the present invention, the pressure control module includes a pressure controller, an axial pressure control component and a confining pressure control component, the axial pressure control component and the confining pressure control component are communicatively connected with the pressure controller, the axial pressure control component is passed through the kettle cover to extend into the filling cavity and abut against the top of the filler, the confining pressure control component is arranged in the filling cavity and is located on the periphery of the filler, the pressure controller controls the axial pressure control component to move in the vertical direction, and the pressure controller controls the confining pressure control component to move in the radial direction to control the filler to simulate the environmental pressure of the saltwater layer.

[0016] In an embodiment of the first aspect of the present invention, the reactor further comprises an injection well, the length direction of the injection well being arranged along the horizontal direction and / or the vertical direction, and a plurality of injection wells are provided. The liquid injection module and the gas injection module are connected to the injection well so as to be suitable for injecting liquid and gas into the filling cavity through the injection well.

[0017] In an embodiment of the first aspect of the present invention, the filler is provided with a first depth layer, a second depth layer and a third depth layer in sequence from top to bottom, the length direction of the injection well is arranged in the horizontal direction, and the injection well includes a first horizontal well, a second horizontal well and a third horizontal well, all of which are penetrated through the side wall of the kettle body; the first horizontal well, the second horizontal well and the third horizontal well are each provided with a plurality, a plurality of the first horizontal wells extend horizontally into the first depth layer and are arranged at intervals along the circumferential direction, a plurality of the second horizontal wells extend horizontally into the second depth layer and are arranged at intervals along the circumferential direction, a plurality of the third horizontal wells extend horizontally into the third depth layer and are arranged at intervals along the circumferential direction; the lengths of the first horizontal well, the second horizontal well and the third horizontal well are the same.

[0018] In an embodiment of the first aspect of the present invention, the filler is provided with a first depth layer, a second depth layer and a third depth layer in sequence from top to bottom, the length direction of the injection well is arranged along the vertical direction, and the injection well comprises a first vertical well, a second vertical well and a third vertical well, all of which are penetrated through the kettle cover, the first vertical well, the second vertical well and the third vertical well are each provided in plurality and distributed in an array, the first vertical well has a first length and its bottom extends to the first depth layer, the second vertical well has a second length and its bottom extends to the second depth layer, the third vertical well has a third length and its bottom extends to the third depth layer, and the third length is greater than the second length and greater than the first length.

[0019] In an embodiment of the first aspect of the present invention, the gas injection module includes a gas preparation device and a first driving pump group, and the first driving pump group is arranged between the gas preparation device and the injection well, so as to be suitable for injecting CO2 in the gas preparation device into the injection well.

[0020] In an embodiment of the first aspect of the present invention, the gas preparation device includes a gas supply bottle and a high-pressure storage tank, the first drive pump group is arranged between the gas supply bottle and the high-pressure storage tank to increase the pressure of CO2, and the gas injection module also includes a first heating element, which is arranged on the periphery of the high-pressure storage tank to increase the temperature of CO2.

[0021] In an embodiment of the first aspect of the present invention, the liquid injection module includes a second driving pump group, a high-pressure liquid container and a second heating element. The second driving pump group is arranged between the high-pressure liquid container and the injection well to be suitable for injecting the liquid in the high-pressure liquid container into the injection well. The second heating element is arranged on the periphery of the high-pressure liquid container to be suitable for heating the liquid.

[0022] In an embodiment of the first aspect of the present invention, a sealing member is provided at the interface between the kettle body, the kettle cover, the confining pressure control member and the axial pressure control member.

[0023] In the first aspect of the embodiment of the present invention, the data acquisition module includes a mounting shaft, a connecting joint, and a sensor module. The mounting shaft is vertically penetrated through the kettle base, and a receiving groove is provided at the bottom of the kettle base. The connecting joint is provided at one end of the mounting shaft and is located in the receiving groove. The sensor module is provided with multiple sensor modules and is spaced apart on the mounting shaft in the vertical direction. The sensor module is communicatively connected with the connecting joint.

[0024] In an embodiment of the first aspect of the present invention, the sensor module includes a temperature sensor, a pressure sensor and a resistivity sensor, and the multiple sensor modules are respectively arranged in the first depth layer, the second depth layer and the third depth layer.

[0025] In the first aspect of the embodiment of the present invention, it also includes a back pressure control module, the top of the kettle cover is provided with a reserved hole, the back pressure control module includes a back pressure plunger pump, a back pressure valve, a liquid collecting tank and a gas collecting tank, one end of the back pressure valve is connected to the reserved hole, and the other end is connected to the back pressure plunger pump, the liquid collecting tank and the gas collecting tank are connected to the back pressure valve through a gas-liquid separator.

[0026] In the first aspect of the present invention, an ultragravity centrifuge basket is also included, and the reactor is arranged on the ultragravity centrifuge basket.

[0027] In a second aspect, the present invention also provides a method for preparing a geological storage model for gas, which is applied to the simulation of CO2 storage in saline aquifers, comprising the following steps:

[0028] A simulated geological layer is prepared by fully stirring and mixing standard sand of simulated original particle size with quantitative deionized water to prepare sand with a specific moisture content, placing the sand with a specific moisture content in a filling cavity of a reactor, and obtaining a specific porosity by a layered compaction method to simulate a saline layer;

[0029] After sealing, test the air tightness. After the reactor is sealed, inject nitrogen through the reserved hole to test the air tightness.

[0030] Loading and setting temperature, placing the reactor in the hanging basket of the ultragravity centrifuge, adjusting the temperature through the servo temperature control module, and controlling the temperature in the reactor to be stable at the set initial temperature;

[0031] Stabilize the gravity field, start the centrifuge, load the centrifugal acceleration to a predetermined acceleration value in a graded acceleration manner, and after the acceleration is stabilized, wait for several hours to allow the simulated geological layer to be fully consolidated under the hypergravity field;

[0032] Ambient temperature and ambient pressure regulation: the temperature of the reactor is regulated by the servo temperature control module so that the temperature of the simulated geological layer rises to the ambient temperature of the saltwater layer; the pressure in the filling chamber is controlled by the pressure control module so that the pressure of the simulated geological layer rises to the ambient pressure of the saltwater layer;

[0033] Liquid injection: Use the liquid injection module to inject formation water or oil and gas into the upper and lower sides of the reactor to reach a predetermined pressure.

[0034] In a third aspect, the present invention also provides a geological storage method for gas, which is applied to the simulation of CO2 storage in saline aquifers, and comprises the following steps:

[0035] The back pressure control module is used to adjust the pressure at a predetermined rate to gradually increase or decrease the pressure in the filling chamber to a production target value, and the servo temperature control module is used to maintain the temperature environment and geothermal gradient in the filling chamber unchanged;

[0036] CO2 is injected into the filling cavity through a gas injection module; CO2 enters the saline layer to displace the saline water, and the saline water enters the liquid collection tank through a gas-liquid separator. When the CO2 displacement is completed and gas is detected in the gas collection tank, the CO2 saline layer sealing is completed;

[0037] The parameter changes during the gas storage process are detected by the data acquisition module to obtain the experimental simulation parameter changes;

[0038] After sealing is completed, the centrifugal acceleration is gradually reduced to 1g, the pressure in the filling chamber is released to normal pressure, and then the reactor is opened to clean the internal fillings. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 A schematic diagram of a flow chart of a simulation device suitable for gas geological storage according to an embodiment of the first aspect of the present invention;

[0041] Figure 2 A three-dimensional plan view of a simulation device suitable for gas geological storage according to an embodiment of the first aspect of the present invention;

[0042] Figure 3 It is a cross-sectional schematic diagram of a reaction kettle according to an embodiment of the first aspect of the present invention;

[0043] Figure 4 It is a schematic structural diagram of a gas injection module according to an embodiment of the first aspect of the present invention;

[0044] Figure 5 It is a structural schematic diagram of a back pressure control module according to an embodiment of the first aspect of the present invention.

[0045] Description of reference numerals:

[0046] 1. Reactor; 11. Reactor body; 12. Reactor cover; 13. Reactor seat; 14. Injection well; 15. Filling chamber; 2. Environmental parameter control module; 21. Pressure control module; 22. Servo temperature control module; 211. Axial pressure control component; 212. Confining pressure control component; 221. Heating component; 3. Liquid injection module; 4. Gas injection module; 41. Gas supply bottle; 42. First drive pump group; 43. High-pressure storage tank; 44. First heating component; 5. Data acquisition module; 51. Mounting shaft; 52. Connection interface; 53. Sensor module; 6. Back pressure control module; 61. Back pressure plunger pump; 62. Back pressure valve; 63. Liquid collection tank; 64. Gas-liquid separator; 65. Gas collection tank. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0048] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0049] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0051] Reference Figure 1 , Figure 2 and Figure 3 As shown, in the first aspect of the present invention, the present invention provides a simulation device suitable for gas geological storage, which is applied to the storage simulation of CO2 in saline water layers, including: a reactor 1, an environmental parameter control module 2, a liquid injection module 3, a gas injection module 4 and a data acquisition module 5; a filling chamber 15 is provided inside the reactor 1, and a filler is provided in the filling chamber 15 to simulate the saline water layer; the environmental parameter control module 2 is arranged in the reactor 1 to control the environmental parameters of the filling chamber 15 to simulate the saline water layer environment; the liquid injection module 3 and the gas injection module 4 are both connected to the filling chamber 15 to be suitable for introducing liquid and gaseous CO2 into the filling chamber 15; the data acquisition module 5 is arranged in the filling chamber 15 and is located in the filler, and the data acquisition module 5 is suitable for detecting changes in temperature parameters, pressure parameters and resistivity parameters of the filler after CO2 is injected into the filling chamber 15.

[0052] Specifically, the filler is arranged in the filling cavity 15, and the environmental parameters of the filling cavity 15 are controlled by the environmental parameter control module to simulate the environmental parameters of the saline layer. The liquid injection module 3 is connected to the filling cavity 15 to inject liquid into the filling cavity 15 to form saline water. After setting the environmental parameters of the saline layer and injecting the liquid, the gas injection module 4 is connected to the filling cavity 15, and CO2 is injected into the filling cavity 15 to discharge the saline water, thereby realizing the sealing of CO2. In this process, the data acquisition module 5 is used to monitor the changes in temperature parameters, pressure parameters and resistivity parameters during the gas sealing process, so as to obtain the simulation experiment parameters. The simulation device suitable for geological sealing of gas controls the geological environmental parameters in real time through the environmental parameter control module 2 to ensure that the variables are controllable during the simulation process, so as to ensure the accuracy of the simulation experiment. At the same time, the data acquisition module 5 is used to monitor the parameter changes of the saline layer during the gas sealing process in real time, so as to obtain accurate simulation experiment parameters.

[0053] In the first aspect of the embodiment of the present invention, the environmental parameters include temperature parameters and pressure parameters. The environmental parameter control module 2 includes a servo temperature control module 22 and a pressure control module 21. The servo temperature control module 22 is suitable for controlling the temperature parameters of the filler to simulate the environmental temperature of the saltwater layer; the pressure control module 21 is suitable for controlling the pressure parameters of the filling chamber 15 to simulate the environmental pressure of the saltwater layer.

[0054] Specifically, the servo temperature control module 22 is used to control the temperature parameters of the filling material in the filling chamber 15 so that the temperature of the filling material is consistent with the temperature of the saltwater layer, so as to be suitable for simulating the environmental temperature of the saltwater layer. The pressure control module 21 is suitable for controlling the pressure parameters of the filling chamber 15 so as to be suitable for simulating the environmental pressure of the saltwater layer. Before the gas is sealed, the pressure parameters and temperature parameters of the filling chamber 15 in the reactor 1 are adjusted by the servo temperature control module 22 and the pressure control module 21 to reach the environmental parameters of the saltwater layer, thereby simulating the sealing state of CO2 in the saltwater layer. During the sealing process, the servo temperature control module 22 and the pressure control module 21 are controlled in real time to ensure the stability of the simulation state, and at the same time ensure the stability of the simulation variables, so as to obtain high-precision simulation parameters.

[0055] In the first aspect of the embodiment of the present invention, the reaction kettle 1 includes a kettle base 13, a kettle body 11 and a kettle cover 12 which are separately arranged. The two ends of the kettle body 11 are fixedly connected to the kettle base 13 and the kettle cover 12 by fasteners to enclose a filling cavity 15. The data acquisition module 5 is penetrated through the kettle base 13 and partially extends into the filling cavity 15.

[0056] Specifically, the reactor 1 is a cylindrical sealed structure, and the reactor base 13, the reactor body 11 and the reactor cover 12 are separately connected and enclosed to form a closed filling cavity 15, and the filler is placed in the filling cavity 15 to simulate the saline layer. The data acquisition module 5 is arranged through the reactor base 13 and extends into the filling cavity 15 to be wrapped by the filler. During the simulated gas sealing process, the temperature parameters, pressure parameters and resistivity parameters in the simulated saline layer are collected and monitored by the data acquisition module 5, so as to obtain accurate simulation data.

[0057] It can be understood that the kettle base 13, kettle body 11 and kettle cover 12 are all made of titanium alloy material, can work under the condition of maximum centrifugal acceleration of 500g, with a pressure range of 0 to 50MPa, an inner diameter of 600mm, an inner height of 200mm, and a volume of about 207L.

[0058] In the first aspect of the present invention, the servo temperature control module 22 includes a temperature controller and a heating component 221. The heating component 221 is arranged on the periphery of the kettle body 11 and / or in the filling cavity 15. The temperature controller controls the heating component 221 to heat so as to be suitable for simulating the ambient temperature of the saltwater layer.

[0059] In the first embodiment of the present invention, the heating assembly 221 is a heating jacket and / or a heating plate. The heating jacket is arranged on the periphery of the kettle body 11, and the heating plate is arranged at the bottom of the filling cavity 15. The heating jacket and the heating plate are communicatively connected to the temperature controller.

[0060] Specifically, the heating component 221 is a heating jacket and / or a heating plate, wherein the heating jacket can be sleeved on the outer periphery of the kettle body 11, and the heating plate can be placed at the bottom of the filling cavity 15, that is, the upper end surface of the kettle seat 13. The heating jacket is an elastic jacket, and the heating jacket is heated by water bath heating to increase the temperature of the filling cavity 15, and the heating controller is a constant temperature water bath. A water bath guide plate is also provided between the kettle body 11 and the heating jacket to guide the water bath circulation path. The heating plate and the heating jacket are connected to the temperature controller in series or in parallel, so as to control the temperature gradient in the filling cavity 15 to simulate the high temperature environment of the deep saline water layer, wherein the high temperature of the saline water layer is 40°C-90°C.

[0061] In the first aspect of the embodiment of the present invention, the pressure control module 21 includes a pressure controller, an axial pressure control component 211 and a confining pressure control component 212. The axial pressure control component 211 and the confining pressure control component 212 are communicatively connected with the pressure controller. The axial pressure control component 211 is penetrated through the kettle cover 12 to extend into the filling cavity 15 and abuts against the top of the filler. The confining pressure control component 212 is arranged in the filling cavity 15 and is located on the periphery of the filler. The pressure controller controls the axial pressure control component 211 to move in the vertical direction, and the pressure controller controls the confining pressure control component 212 to move in the radial direction to control the environmental pressure of the filler to simulate the saline layer.

[0062] Specifically, the axial pressure control component 211 includes an axial pressure piston and an axial pressure plunger pump. The driving end of the axial pressure plunger pump is transmission-connected to the axial pressure piston. The pressure control key controls the start-up of the axial pressure plunger pump to control the axial movement of the axial pressure piston, thereby realizing pressurization or decompression of the filling chamber 15. The confining pressure control component 212 includes a shrinkage jacket. The two ends of the shrinkage jacket are respectively sealed with the kettle cover 12 and the kettle seat 13. Water is injected into the shrinkage jacket through the confining pressure plunger pump to ensure the stability of the formation confining pressure. The start-up of the confining pressure plunger pump is controlled by the pressure controller to control the amount of water injection, thereby controlling the shrinkage or expansion of the shrinkage jacket.

[0063] It is understandable that, through the pressure controller, the axial pressure control component 211 and the confining pressure control component 212 are controlled in real time, so that the filling in the filling cavity 15 can simulate the environmental pressure of the real saltwater layer to improve the authenticity of the simulation. At the same time, the pressure control module 21 can control the pressure variable in real time during the gas sealing process to reduce the simulation error.

[0064] In the first aspect of the embodiment of the present invention, the reactor 1 also includes an injection well 14, the length direction of the injection well 14 is arranged along the horizontal direction and / or the vertical direction, and there are multiple injection wells 14. The liquid injection module 3 and the gas injection module 4 are connected to the injection well 14 to be suitable for injecting liquid and gas into the filling cavity 15 through the injection well 14.

[0065] Specifically, the gas injection module 4 and the liquid injection module 3 are both connected to the injection well 14, and the liquid is injected into the filling cavity 15 through the injection well 14 to simulate the saltwater environment of the saltwater layer, and CO2 is introduced through the injection well 14 to discharge the saltwater, thereby simulating the storage of CO2. According to experimental needs, the length direction of the injection well 14 can be set to be set in the horizontal direction and / or in the vertical direction.

[0066] It can be understood that by setting up multiple injection wells 14, the injection efficiency of liquid / gas is improved to improve the simulation efficiency. In addition, by setting up multiple injection wells 14, uniform injection of liquid is achieved to improve the authenticity of the simulation of the saltwater layer.

[0067] In the first aspect of the embodiment of the present invention, the filler is provided with a first depth layer, a second depth layer and a third depth layer in sequence from top to bottom, the length direction of the injection well 14 is arranged in the horizontal direction, and the injection well 14 includes a first horizontal well, a second horizontal well and a third horizontal well all of which are penetrated through the side wall of the kettle body 11; the first horizontal well, the second horizontal well and the third horizontal well are each provided with a plurality of first horizontal wells, the plurality of second horizontal wells extend horizontally into the first depth layer and are arranged at intervals along the circumferential direction, the plurality of third horizontal wells extend horizontally into the third depth layer and are arranged at intervals along the circumferential direction; the lengths of the first horizontal well, the second horizontal well and the third horizontal well are the same.

[0068] In the first aspect of the embodiment of the present invention, the filler is provided with a first depth layer, a second depth layer and a third depth layer in sequence from top to bottom, the length direction of the injection well 14 is arranged along the vertical direction, the injection well 14 includes a first vertical well, a second vertical well and a third vertical well all of which are penetrated through the kettle cover 12, the first vertical well, the second vertical well and the third vertical well are each provided with a plurality and distributed in an array, the first vertical well has a first length and its bottom extends to the first depth layer, the second vertical well has a second length and its bottom extends to the second depth layer, the third vertical well has a third length and its bottom extends to the third depth layer, and the third length is greater than the second length and greater than the first length.

[0069] Specifically, by dividing the filling material into three different depth layers from top to bottom, namely the first depth layer, the second depth layer and the third depth layer, multiple injection wells 14 are drilled in different depth layers to simulate the state of CO2 storage at different depths, thereby obtaining a variety of simulation experiment parameters and improving the integrity of the simulation experiment.

[0070] In the first embodiment of the present invention, the gas injection module 4 includes a gas preparation device and a first drive pump group 42. The first drive pump group 42 is arranged between the gas preparation device and the injection well 14 to be suitable for injecting CO2 in the gas preparation device into the injection well 14.

[0071] Reference Figure 4 As shown, in the embodiment of the first aspect of the present invention, the gas preparation device includes a gas supply bottle 41 and a high-pressure storage tank 43, and the first driving pump group 42 is arranged between the gas supply bottle 41 and the high-pressure storage tank 43 to increase the pressure of CO2. The gas injection module 4 also includes a first heating element 44, and the first heating element 44 is arranged on the periphery of the high-pressure storage tank 43 to increase the temperature of CO2.

[0072] Specifically, the gas supply bottle 41 stores CO2 at normal temperature and pressure. A first drive pump group 42 is set between the gas supply bottle 41 and the high-pressure storage tank 43. The first drive pump group 42 is a gas booster pump and an air compressor. The CO2 is pressurized by the first drive pump group 42. A first heating element 44 is set on the periphery of the high-pressure storage tank 43. The first heating element 44 is a thermocouple jacket. After being heated by the first heating element 44, the CO2 in the high-pressure storage tank 43 is in a supercritical state to meet the sealing state. A gas flow control valve and a one-way valve are set between the high-pressure storage tank 43 and the injection well 14 to ensure that CO2 is injected into the filling cavity 15 in a one-way manner, simulating the sealing state of CO2 in the saline layer geology.

[0073] In the first aspect embodiment of the present invention, the liquid injection module 3 includes a second driving pump group, a high-pressure liquid container and a second heating element. The second driving pump group is arranged between the high-pressure liquid container and the injection well 14 to be suitable for injecting the liquid in the high-pressure liquid container into the injection well 14. The second heating element is arranged on the periphery of the high-pressure liquid container to be suitable for heating the liquid.

[0074] Specifically, multiple high-pressure liquid containers can be provided to store different types of liquids respectively, so as to be suitable for simulating saline water layers. A second heating element is provided on the periphery of the high-pressure liquid container, and the second heating element is a thermocouple jacket. By heating the high-pressure liquid container, the temperature of the liquid can be accurately controlled to simulate the temperature of deep water or deep oil.

[0075] In the first embodiment of the present invention, sealing members are provided at the interfaces between the kettle body 11 , the kettle cover 12 , the confining pressure control member 212 and the axial pressure control member 211 .

[0076] Specifically, a sealing member is provided to ensure the sealing performance of the filling chamber 15 during the simulation process, thereby improving the experimental accuracy of the simulated CO2 storage.

[0077] In the first aspect of the embodiment of the present invention, the data acquisition module 5 includes an installation shaft 51, a connecting joint, and a sensor module. The installation shaft 51 is vertically penetrated in the kettle base 13. A receiving groove is provided at the bottom of the kettle base 13. The connecting joint is provided at one end of the installation shaft 51 and is located in the receiving groove. A plurality of sensor modules are provided and are spaced apart on the installation shaft 51 in the vertical direction. The sensor module is communicatively connected with the connecting joint.

[0078] In an embodiment of the first aspect of the present invention, the sensor module includes a temperature sensor, a pressure sensor and a resistivity sensor, and the multiple sensor modules are respectively arranged in the first depth layer, the second depth layer and the third depth layer.

[0079] Specifically, the installation shaft 51 is vertically penetrated in the kettle seat 13 and extends into the filling cavity 15, the connection joint is arranged at one end of the installation shaft 51 and placed in the receiving groove, and multiple sensor modules are arranged at intervals along the length direction of the installation shaft 51 to detect experimental parameters at different depths. The sensor modules include temperature sensors, pore pressure sensors, resistivity, soil pressure boxes, displacement sensors, flow meters, and acoustic wave monitoring; each sensor module is connected to a data acquisition system, which is composed of a PLC, a switch, a serial port server, a multi-channel data acquisition device, a fiber optic transceiver, and a computer. The real-time control and acquisition of data is realized through the computer as a whole.

[0080] Reference Figure 5 As shown, in the embodiment of the first aspect of the present invention, a back pressure control module 6 is also included. A reserved hole is provided on the top of the kettle cover 12. The back pressure control module 6 includes a back pressure plunger pump 61, a back pressure valve 62, a liquid collecting tank 63 and a gas collecting tank 65. One end of the back pressure valve 62 is connected to the reserved hole, and the other end is connected to the back pressure plunger pump 61. The liquid collecting tank 63 and the gas collecting tank 65 are connected to the back pressure valve 62 through a gas-liquid separator 64.

[0081] Specifically, the back pressure control module 6 includes a back pressure plunger pump 61, a back pressure valve 62, a gas-liquid separator 64, a liquid collection tank 63 and a gas collection tank 65. One end of the back pressure valve 62 is connected to the reserved hole, and the other end is connected to the back pressure plunger pump 61 to control the pressure boundary, control the back pressure plunger pump to be above 8MPa, ensure the formation pore pressure environment, and the existence conditions of supercritical CO2. The gas-liquid separator 64 connects the liquid collection tank 63 and the gas collection tank 65. When supercritical CO2 is displaced through the injection well 14, the salt water enters the gas-liquid separator 64 through the back pressure valve 62, the formation salt water enters the liquid collection tank 63 for collection, and the gas enters the gas collection tank 65 for collection. It can be understood that when CO2 is detected in the gas collection tank 65, the sealing of CO2 is completed. The mass of salt water collected by the liquid collection tank 63 can accurately calculate the residual water saturation of the salt water layer and the CO2 sealing efficiency.

[0082] In the first aspect of the present invention, an ultragravity centrifuge basket is also included, and the reactor 1 is arranged on the ultragravity centrifuge basket.

[0083] Specifically, the simulation experiment is carried out in an ultra-gravity centrifugal environment. The ultra-gravity centrifuge basket geotechnical centrifuge includes a hanging basket, a power room, a rotating shaft, a rotating arm, and water / gas pipelines. Each module can work under ultra-gravity centrifugal acceleration conditions of 1 to 500g.

[0084] In a second aspect, the present invention also provides a method for preparing a geological storage model for gas, which is applied to the storage simulation of CO2 in a saline layer, comprising the following steps:

[0085] Prepare a simulated geological layer by fully stirring and mixing standard sand of simulated original particle size with quantitative deionized water to prepare sand with specific moisture content, place the sand with specific moisture content in the filling cavity 15 of the reactor 1, and obtain a specific porosity by layered compaction method to simulate a saline layer;

[0086] After sealing, check air tightness. After the reactor 1 is sealed, nitrogen is injected through the reserved hole to check air tightness.

[0087] Loading and setting temperature, loading the reactor 1 into the hanging basket of the ultragravity centrifuge, adjusting the temperature through the servo temperature control module 22, and controlling the temperature in the reactor 1 to be stable at the set initial temperature;

[0088] Stabilize the gravity field, start the centrifuge, and load the centrifugal acceleration to a predetermined acceleration value in a graded acceleration manner. After the acceleration is stabilized, wait for several hours to allow the simulated geological layer to be fully consolidated under the hypergravity field;

[0089] Ambient temperature and ambient pressure regulation: the temperature of the reactor 1 is regulated by the servo temperature control module 22 so that the temperature of the simulated geological layer rises to the ambient temperature of the saline layer; the pressure in the filling chamber 15 is controlled by the pressure control module 21 so that the pressure of the simulated geological layer rises to the ambient pressure of the saline layer;

[0090] Liquid injection: Use the liquid injection module 3 to inject formation water or oil and gas into the upper and lower sides of the reactor to reach a predetermined pressure.

[0091] In a third aspect, the present invention also provides a geological storage method for gas, which is applied to the simulation of CO2 storage in saline aquifers, and comprises the following steps:

[0092] The back pressure control module 6 adjusts the pressure at a predetermined pressure reduction rate to gradually increase or decrease the pressure in the filling chamber 15 to the mining target value, and the servo temperature control module 22 is used to maintain the temperature environment and geothermal gradient in the filling chamber 15 unchanged;

[0093] CO2 is introduced into the filling chamber 15 through the gas injection module 4; CO2 enters the saline layer to displace the saline water, and the saline water enters the liquid collection tank 63 through the gas-liquid separator 64. When the CO2 displacement is completed and gas is detected in the gas collection tank 65, the CO2 saline layer sealing is completed;

[0094] The data acquisition module 5 detects parameter changes during the gas storage process to obtain experimental simulation parameters;

[0095] After sealing is completed, the centrifugal acceleration is gradually reduced to 1g, and after the pressure in the filling chamber 15 is released to normal pressure, the reactor 1 is opened to clean the internal fillings.

[0096] Specifically, when preparing the device model, firstly, in the filling cavity 15, standard sand simulating the original soil particle gradation and quantitative deionized water are fully stirred and mixed to prepare sand with a specific moisture content, and a soil skeleton with a porosity similar to that of the in-situ reservoir of the saline layer (about 0.1) is prepared by a layered compaction method, i.e., a saline layer reservoir model;

[0097] Afterwards, the reactor is installed above the saline water layer reservoir skeleton, and the confining pressure control component 212 is fully fitted with the soil skeleton to ensure the sealed connection between the confining pressure control component 212 and the reactor 1; an axial pressure control component 211 is added above the saline water layer reservoir model, and a seal is set between the axial pressure control component 211 and the confining pressure control component 212, and then the reactor cover 12 is closed; after closing the reactor cover 12, nitrogen is injected into the reserved hole to perform an air tightness test on the device, and if the air tightness is good, subsequent preparation work is carried out.

[0098] The simulation device is loaded into the basket of the ultragravity centrifuge, and the servo temperature control module 22 is turned on to adjust the temperature, so that the temperature inside the container cylinder is stabilized at a specified initial temperature;

[0099] The centrifuge is started, and the centrifugal acceleration is increased to a predetermined acceleration value in a graded acceleration manner. After the acceleration is stable, several hours are waited to allow the model reservoir skeleton to be fully consolidated under the hypergravity field;

[0100] After adjusting the temperature controller to the predetermined preparation temperature, the high-temperature oil bath circulation is started. Under the action of the high-temperature circulating oil bath, the temperature in the filling cavity 15 is raised to the formation temperature condition. At this time, the temperature of the filling cavity 15 is within the range of supercritical CO2, which is suitable for supercritical CO2 injection and will not produce a large phase change;

[0101] Deionized water is injected into the upper part of the axial loading piston from the top of the kettle cover 12 at a constant pressure by an axial pressure plunger pump to provide overburden pressure for the saline layer reservoir model; deionized water is injected into the interlayer of the shrink jacket from the side of the kettle body 11 at a constant pressure by a confining pressure plunger pump to provide formation confining pressure for the saline layer reservoir model;

[0102] The liquid injection module 3 is used to inject formation water or oil and gas from the injection well 14 into the upper and lower sides of the reactor to reach a predetermined pressure;

[0103] After the pressure and temperature values ​​detected by the sensor and the data acquisition system inside the filling chamber 15 are stabilized, the back pressure pump is used to adjust the pressure in the back pressure valve 62 at a predetermined pressure reduction rate to gradually increase or reduce the pressure in the injection well 14 to the target value. In this process, the axial pressure control component 211 is used to servo-regulate the pressure of the overlying water layer to maintain a constant pressure of the seawater layer above the reservoir when CO2 is injected into the injection well 14, and the servo temperature control module 22 is used to maintain the in-situ saltwater reservoir temperature environment and geothermal gradient unchanged;

[0104] After supercritical CO2 is injected into the saline layer to displace the saline water, the saline water enters the liquid collection tank 63 through the gas-liquid separator 64. When the supercritical CO2 displacement is completed and the gas flow meter and the gas collection tank 65 detect the gas, the supercritical CO2 saline layer is sealed. After the sealing is completed, the centrifugal acceleration is gradually reduced to 1g, and the pressure in the container cylinder is released to normal pressure, and then the kettle cover 12 is opened to clean the internal sample.

[0105] It can be understood that, through the simulation device suitable for gas geological storage, a CO2 storage simulation experiment in a saline layer can be realized. During the simulation process, variables are controlled in real time, thereby simplifying the simulation process, improving the accuracy of the simulation experiment, and obtaining high-precision simulation experiment data.

[0106] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A simulation device suitable for gas geological storage, used for CO2 storage simulation in saline aquifers, characterized in that: include: A reaction kettle (1) is provided with a filling chamber (15) therein, wherein a filling material is provided in the filling chamber (15) so as to be suitable for simulating a saltwater layer; An environmental parameter control module (2) is arranged in the reaction kettle (1) and is suitable for controlling the environmental parameters of the filling chamber (15), wherein the environmental parameters include temperature parameters and pressure parameters. The environmental parameter control module (2) includes a servo temperature control module (22) and a pressure control module (21). The servo temperature control module (22) is suitable for controlling the temperature parameters of the filling material so as to simulate the environmental temperature of the saltwater layer; and the pressure control module (21) is suitable for controlling the pressure parameters of the filling chamber (15) so as to simulate the environmental pressure of the saltwater layer. a liquid injection module (3) and a gas injection module (4), wherein the liquid injection module (3) and the gas injection module (4) are both in communication with the filling chamber (15) so as to be suitable for introducing liquid and gaseous CO2 into the filling chamber (15); A data acquisition module (5) is disposed in the filling cavity (15) and is located in the filling material, the data acquisition module (5) being suitable for detecting changes in temperature parameters, pressure parameters and resistivity parameters of the filling material after the CO2 is injected into the filling cavity (15); The reaction kettle (1) comprises a kettle base (13), a kettle body (11) and a kettle cover (12) which are separately arranged; two ends of the kettle body (11) are respectively fixedly connected to the kettle base (13) and the kettle cover (12) by fasteners to enclose a filling cavity (15); the data acquisition module (5) is arranged through the kettle base (13) and partially extends into the filling cavity (15); The pressure control module (21) comprises a pressure controller, an axial pressure control component (211) and a confining pressure control component (212); the axial pressure control component (211) and the confining pressure control component (212) are in communication with the pressure controller; the axial pressure control component (211) is disposed through the kettle cover (12) to extend into the filling cavity (15) and abut against the top of the filler; the confining pressure control component (212) is disposed in the filling cavity (15) and is located at the periphery of the filler; the pressure controller controls the axial pressure control component (211) to move in a vertical direction; and the pressure controller controls the confining pressure control component (212) to move in a radial direction, so as to control the filler to simulate the environmental pressure of the saltwater layer.

2. The simulation device for gas geological storage according to claim 1, characterized in that: The servo temperature control module (22) comprises a temperature controller and a heating component (221); the heating component (221) is arranged on the periphery of the kettle body (11) and / or in the filling cavity (15); the temperature controller controls the heating component (221) to heat so as to simulate the ambient temperature of the saltwater layer.

3. The simulation device for gas geological storage according to claim 2, characterized in that: The heating assembly (221) is a heating jacket and / or a heating plate, the heating jacket is arranged on the outer periphery of the kettle body (11), the heating plate is arranged on the bottom of the filling cavity (15), and the heating jacket and the heating plate are communicatively connected to the temperature controller.

4. The simulation device for gas geological storage according to claim 2, characterized in that: The reactor (1) further comprises an injection well (14), wherein the length direction of the injection well (14) is arranged along the horizontal direction and / or the vertical direction, and a plurality of the injection wells (14) are provided. The liquid injection module (3) and the gas injection module (4) are connected to the injection well (14) so ​​as to be suitable for injecting liquid and gas into the filling cavity (15) through the injection well (14).

5. The simulation device for gas geological storage according to claim 4, characterized in that: The gas injection module (4) comprises a gas preparation device and a first drive pump group (42); the first drive pump group (42) is arranged between the gas preparation device and the injection well (14) so ​​as to be suitable for injecting CO2 in the gas preparation device into the injection well (14).

6. The simulation device for gas geological storage according to claim 5, characterized in that: The gas preparation device comprises a gas supply bottle (41) and a high-pressure storage tank (43), the first driving pump group (42) is arranged between the gas supply bottle (41) and the high-pressure storage tank (43) to increase the pressure of CO2, and the gas injection module (4) further comprises a first heating element (44), the first heating element (44) is arranged on the periphery of the high-pressure storage tank (43) to increase the temperature of CO2.

7. The simulation device for gas geological storage according to claim 6, characterized in that: The liquid injection module (3) comprises a second drive pump group, a high-pressure liquid container and a second heating element, wherein the second drive pump group is arranged between the high-pressure liquid container and the injection well (14) so ​​as to be suitable for injecting the liquid in the high-pressure liquid container into the injection well (14), and the second heating element is arranged on the periphery of the high-pressure liquid container so as to be suitable for heating the liquid.

8. The simulation device for gas geological storage according to claim 1, characterized in that: The data acquisition module (5) comprises a mounting shaft (51), a connecting joint, and a sensor module; the mounting shaft (51) is vertically penetrated through the kettle base (13); a receiving groove is provided at the bottom of the kettle base (13); the connecting joint is provided at one end of the mounting shaft (51) and is located in the receiving groove; a plurality of sensor modules are provided and are spaced apart on the mounting shaft (51) in the vertical direction; and the sensor module is communicatively connected to the connecting joint.

9. The simulation device for gas geological storage according to claim 8, characterized in that: The filler is provided with a first depth layer, a second depth layer and a third depth layer in sequence from top to bottom, the sensor module includes a temperature sensor, a pressure sensor and a resistivity sensor, and a plurality of sensor modules are respectively provided in the first depth layer, the second depth layer and the third depth layer.

10. The simulation device for gas geological storage according to any one of claims 1 to 9, characterized in that: The kettle cover (12) further comprises a back-pressure control module (6). A reserved hole is provided on the top of the kettle cover (12). The back-pressure control module (6) comprises a back-pressure plunger pump (61), a back-pressure valve (62), a liquid collection tank (63) and a gas collection tank (65). One end of the back-pressure valve (62) is connected to the reserved hole, and the other end is connected to the back-pressure plunger pump (61). The liquid collection tank (63) and the gas collection tank (65) are connected to the back-pressure valve (62) via a gas-liquid separator (64).

11. A model preparation method, applicable to the preparation of a simulation device for gas geological storage according to any one of claims 1 to 10, characterized in that: The following steps are involved: Preparing a simulated geological layer by fully stirring and mixing standard sand of simulated original particle size with a certain amount of deionized water to prepare sand with a specific moisture content, placing the sand with a specific moisture content in a filling chamber (15) of a reaction kettle (1), and obtaining a specific porosity by a layered compaction method to simulate a saline layer; After sealing, test the air tightness. After the reaction kettle (1) is sealed, nitrogen is injected through the reserved hole to test the air tightness. Loading and setting the temperature, placing the reactor (1) in the hanging basket of the ultragravity centrifuge, and adjusting the temperature through the servo temperature control module (22) to control the temperature in the reactor (1) to be stable at the set initial temperature; Stabilize the gravity field, start the centrifuge, load the centrifugal acceleration to a predetermined acceleration value in a graded acceleration manner, and after the acceleration is stabilized, wait for several hours to allow the simulated geological layer to be fully consolidated under the hypergravity field; Ambient temperature and ambient pressure regulation: the temperature of the reactor (1) is regulated by the servo temperature control module (22) so that the temperature of the simulated geological layer rises to the ambient temperature of the saltwater layer; the pressure in the filling chamber (15) is controlled by the pressure control module (21) so that the pressure of the simulated geological layer rises to the ambient pressure of the saltwater layer; Liquid injection: using the liquid injection module (3) to inject formation water or oil and gas into the upper and lower sides of the reactor to reach a predetermined pressure.

12. A method for geological storage of gas, using a simulation device for geological storage of gas according to claim 10, characterized in that: The following steps are involved: The back pressure control module (6) is used to adjust the pressure at a predetermined rate so as to gradually increase or decrease the pressure in the filling chamber (15) to a production target value, and the temperature environment and geothermal gradient in the filling chamber (15) are maintained constant by using a servo temperature control module (22); CO2 is introduced into the filling chamber (15) through a gas injection module (4); the CO2 enters the saline water layer to displace the saline water, and the saline water enters the liquid collection tank (63) through a gas-liquid separator (64); when the CO2 displacement is completed and gas is detected in the gas collection tank (65), the CO2 saline water layer sealing is completed; Detecting parameter changes during the gas storage process through a data acquisition module (5) to obtain experimental simulation parameter changes; After sealing is completed, the centrifugal acceleration is gradually reduced to 1g, the pressure in the filling chamber (15) is released to normal pressure, and then the reactor (1) is opened to clean the filling inside.

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