Carbon-sealed storage layer ScCO2 corrosion breakthrough mechanism and permeability evolution experimental device

Abstract

The invention belongs to the technical field of carbon sequestration, and particularly relates to a carbon-sealed storage layer ScCO2 corrosion breakthrough mechanism and permeability evolution experimental device, a main body structure comprises a piston container, a filtering pipeline, a clamp holder, a back pressure pipeline and a gas-liquid separation bottle which are connected in sequence, a filter is arranged on the filtering pipeline, an upstream vacuum stop valve and a downstream vacuum stop valve are arranged at the two ends of the clamping device, balance valves are arranged on the outer sides of the upstream vacuum stop valve and the downstream vacuum stop valve, the back-pressure pipeline is connected with the main pipeline through a back-pressure valve, a buffer container is arranged on the back-pressure pipeline, a gas concentration sensor is arranged in the gas-liquid separation bottle, and an outlet is connected with a balance. The device can simulate the real formation temperature, pressure and fluid conditions, carries out the ScCO2 storage experiment under the simulated formation temperature, pressure and fluid conditions based on a constant-pressure displacement method, and analyzes the adsorption, corrosion and seepage conditions of ScCO2 in a rock core by measuring various parameters under the formation temperature and pressure conditions.

Description

Technical field:

[0001] The present invention belongs to the technical field of carbon storage, and in particular relates to a carbon storage layer ScCO 2 The experimental device for the mechanism of dissolution breakthrough and permeability evolution is used to investigate the CO2 evolution in different geological structures. 2 It provides key data support for storage suitability evaluation. Background technology:

[0002] With the introduction of carbon peak and carbon neutrality goals, how to effectively solve the carbon emission problem has become a research hotspot. Carbon dioxide capture, utilization and storage technology (CCUS), which can effectively improve the carbon emission problem, is an important and indispensable technical choice to support the carbon peak and carbon neutrality goals.

[0003] CO 2 Geological storage is the mainstream research direction of carbon storage. In the depth of 0.8-1.0 km underground, CO 2 With fluid properties, based on CO 2 The physical and chemical properties of carbon can be changed to achieve geological carbon storage. 2 geological structures, including deep saline aquifers, depleted oil and gas fields, unmineable coal seams, abandoned salt mines, and basalt aquifers.

[0004] The reservoir storage capacity of carbon geological storage is crucial. 2 It is a relatively active substance. After being injected into the reservoir, it will be stored in the adsorbed phase, free phase and dissolved phase. 2 When dissolved in formation water, it will react with minerals, causing mineral precipitation and dissolution, changing the permeability of the reservoir, and thus affecting the storage capacity of the reservoir. 2 During the storage process, ScCO 2 To solve the problem of long-term adsorption and dissolution of reservoirs changing the reservoir sealing capacity, a carbon sealing storage layer ScCO was developed and designed. 2 The experimental device for dissolution breakthrough mechanism and permeability evolution is used to analyze the evolution mechanism of reservoir sealing and to provide reference for the CO2 storage layer in different geological structures. 2 Provide data support for storage suitability evaluation. Summary of the invention:

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and develop a carbon sealing storage layer ScCO 2 The experimental device for dissolution breakthrough mechanism and permeability evolution provides effective guidance for the evaluation of carbon storage capacity of carbon storage layers and for efficient and safe carbon storage.

[0006] In order to achieve the above-mentioned object, the present invention relates to a carbon sealing storage layer ScCO 2 The main structure of the experimental device for the dissolution breakthrough mechanism and permeability evolution includes a piston container, a filter pipeline, a clamp, a back pressure pipeline and a gas-liquid separation bottle connected in sequence;

[0007] The piston container is connected to the CO 2 Gas cylinders and He cylinders are connected;

[0008] A filter is provided on the filter pipeline;

[0009] An upstream vacuum cut-off valve and a downstream vacuum cut-off valve are arranged at both ends of the clamp, and a balancing valve is arranged on the outside of the two valves;

[0010] The back pressure pipeline is connected to the main pipeline through a back pressure valve, and a buffer container is arranged on it;

[0011] A gas concentration sensor is provided in the gas-liquid separation bottle, and the outlet is connected to a balance;

[0012] In addition, an upstream stop valve is arranged between the filter pipeline and the reversing valve, and a downstream stop valve is arranged between the balancing valve and the back pressure valve.

[0013] The main structure of the clamper according to the present invention comprises a cylinder and plugs arranged at both ends thereof, and a confining pressure inlet and a confining pressure outlet arranged in the middle;

[0014] A core sample is arranged between the plugs, the outer sides of the plugs and the core sample are wrapped with a silicone heat shrink tube, and a rubber sleeve is arranged on the outer side of the silicone heat shrink tube.

[0015] The piston container, the filter pipeline, the clamp, the back pressure pipeline and the gas-liquid separation bottle of the present invention are connected through a main pipeline;

[0016] The piston container is driven by a constant pressure power pump;

[0017] The on / off of the filter pipeline is controlled by a vacuum shut-off valve, and the filter with a vacuum gauge inside is driven by a vacuum pump;

[0018] The gripper is driven by a confining pressure pump, the on / off of which is controlled by a confining pressure stop valve, and the pressure is monitored by a confining pressure sensor;

[0019] Pressure sensors are provided at both ends of the balancing valve;

[0020] The buffer container is driven by a back pressure pump, the on and off is controlled by a back pressure stop valve, and the pressure is monitored by a back pressure sensor;

[0021] The plug has an adjustable pressure cap to limit the movement of the core sample;

[0022] A vent stop valve is provided at the confining pressure outlet;

[0023] In addition, both the piston container and the filter line have drain valves.

[0024] The back pressure valve involved in the present invention can establish a set pressure difference between the outlet and the inlet of the clamp according to experimental needs:

[0025] During the process of the back pressure pump loading the set pressure on the back pressure port of the back pressure valve, when the back pressure valve inlet pressure is greater than or equal to the back pressure valve back pressure port loading pressure, the back pressure valve inlet pressure breaks through the back pressure valve, causing the fluid to flow in from the back pressure valve inlet and out from the back pressure valve outlet;

[0026] When the back-pressure pump loads the back-pressure port of the back-pressure valve to the set pressure, the saturated fluid in the pipeline connecting the clamp outlet with the downstream vacuum shut-off valve, the downstream pressure sensor, the downstream shut-off valve and the back-pressure valve, and the saturated fluid in the capillary connected with the back-pressure valve outlet with the gas-liquid separation bottle and the balance are used to accurately calculate the displacement fluid.

[0027] The present invention relates to a carbon sealing storage layer ScCO 2 The specific process steps of the dissolution breakthrough mechanism and permeability evolution experimental device for rock displacement testing are as follows:

[0028] A1. Packaging core

[0029] First, the core is saturated with formation water to obtain a core sample;

[0030] Then, wrap the silicone heat shrink tubing tightly around the outside of the plug and the core sample;

[0031] Finally, put it into a rubber sleeve and place it in the cylinder;

[0032] A2. Apply confining pressure

[0033] Apply confining pressure to the holder. When fluid flows out of the vent stop valve, close the vent stop valve and continue to apply confining pressure to the set value.

[0034] A3. Vacuuming

[0035] First, close the upstream vacuum stop valve, the downstream vacuum stop valve, and the downstream stop valve;

[0036] Then, open the vacuum shut-off valve;

[0037] Finally, turn on the vacuum pump to draw a vacuum;

[0038] A4. Apply back pressure

[0039] Turn on the back pressure pump to apply back pressure to the back pressure port of the back pressure valve;

[0040] A5. Displacement experiment

[0041] First, close the vacuum shut-off valve, the upstream vacuum shut-off valve, and the balancing valve;

[0042] Then, open the upstream stop valve and CO 2 Gas cylinder, adjust the reversing valve to make CO 2 The gas cylinder is connected to the piston container, and CO is injected into the piston container. 2 gas;

[0043] Finally, the internal temperature of the piston container is raised to the set value, and the constant pressure power pump is turned on to pump CO 2 The gas pressure is raised to the set value, and the upstream vacuum shut-off valve is opened for pressure displacement;

[0044] A6. Collecting Data

[0045] Collect data from confining pressure sensors, pressure sensors, back pressure sensors, gas concentration sensors and balances. 2 When breakthrough occurs, record the breakthrough time and breakthrough pressure, and calculate ScCO 2 Breakthrough speed, monitoring CO 2 The amount of gas leaking out.

[0046] The present invention relates to a carbon sealing storage layer ScCO 2 The experimental device for dissolution breakthrough mechanism and permeability evolution uses the overburden permeability test method to simulate the in-situ pressure, temperature and fluid conditions of the carbon-sealed storage layer to reveal the ScCO 2 The permeability evolution characteristics under long-term action are analyzed by core CO 2 The specific process steps for sealing capacity are as follows:

[0047] B1. Vacuuming

[0048] First, close the downstream stop valve;

[0049] Then, open the vacuum stop valve, the upstream vacuum stop valve, the upstream stop valve, the downstream vacuum stop valve and the balancing valve;

[0050] Finally, turn on the vacuum pump to draw a vacuum;

[0051] B2. Apply confining pressure

[0052] Apply confining pressure to the holder. When fluid flows out of the vent stop valve, close the vent stop valve and continue to apply confining pressure to the set pressure.

[0053] B3. Overburden permeability test

[0054] First, close the vacuum shutoff valve;

[0055] Then, open the He gas cylinder, adjust the reversing valve to connect the He gas cylinder with the piston container, and inject He gas into the piston container;

[0056] Finally, the constant pressure power pump is turned on to pressurize the He gas. When the pressure measured by the pressure sensor is the first preset value, the constant pressure power pump is kept at the first preset value pressure and balanced for a set period of time, and then the upstream vacuum shut-off valve and the balance valve are closed. After the constant pressure power pump continues to pressurize to the second preset value, the upstream shut-off valve is closed, and the upstream vacuum shut-off valve is opened for testing.

[0057] B4. Collecting Data

[0058] The data from the confining pressure sensor and the pressure sensor are collected, and the effective gas permeability is calculated based on the collected data.

[0059] Compared with the prior art, the present invention simulates the real formation temperature, pressure, and fluid conditions, and carries out ScCO under the simulated formation temperature, pressure, and fluid conditions based on the constant pressure displacement method. 2 The storage experiment was conducted by measuring the CO2 content downstream of the core under the conditions of formation temperature and pressure. 2 The changes in gas concentration and its relationship with time, core length, saturated fluid, and lithology are analyzed to determine the ScCO 2 The adsorption, dissolution and seepage conditions in the core were investigated. The breakthrough mechanism of the carbon-sealed storage layer was analyzed based on experimental data. 2 The permeability of the long-term adsorption and dissolution reservoir is measured to obtain the permeability evolution characteristics of the carbon-sealed storage layer, determine the sealing properties of the cores of different carbon-sealed storage layers, and reveal the ScCO 2 The evolution mechanism of core permeability under long-term dissolution displacement can provide some insights into the CO2 evolution in different geological structures. 2 Storage suitability evaluation provides key data support and effective guidance for efficient and safe carbon storage. Description of the drawings:

[0060] Figure 1 It is a schematic diagram of the main structural principle of the present invention.

[0061] Figure 2 The present invention is a schematic diagram of the main structural principle of the clamper. Specific implementation method:

[0062] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0063] Embodiment 1:

[0064] The carbon sealing storage layer ScCO involved in this embodiment 2 The main structure of the experimental device for dissolution breakthrough mechanism and permeability evolution is as follows: Figure 1As shown, it includes a main pipeline 1, a piston container 2, a filter pipeline 3, a clamp 4, a back pressure pipeline 5, a gas-liquid separation bottle 6, a constant pressure power pump 7, a reversing valve 8, a CO 2 Gas cylinder 9, He gas cylinder 10, vacuum stop valve 11, filter 12, vacuum pump 13, vacuum gauge 14, confining pressure pump 15, upstream vacuum stop valve 16, downstream vacuum stop valve 17, confining pressure stop valve 18, confining pressure sensor 19, balancing valve 20, pressure sensor 21, back pressure valve 22, buffer container 23, back pressure pump 24, back pressure stop valve 25, back pressure sensor 26, gas concentration sensor 27, balance 28, upstream stop valve 29, downstream stop valve 30 and vent valve 31;

[0065] The main pipeline 1 is provided with a piston container 2, a filter pipeline 3, a clamp 4, a back pressure pipeline 5 and a gas-liquid separation bottle 6 in sequence;

[0066] The piston container 2 driven by the constant pressure power pump 7 is connected to the CO 2 The gas cylinder 9 is connected to the He gas cylinder 10;

[0067] A filter 12 is provided on the filter pipeline 3 whose on / off is controlled by a vacuum stop valve 11, and a vacuum gauge 14 is provided in the filter 12 driven by a vacuum pump 13;

[0068] An upstream vacuum cut-off valve 16 and a downstream vacuum cut-off valve 17 are provided at both ends of the clamp 4 driven by a confining pressure pump 15. The on and off of the confining pressure pump 15 is controlled by a confining pressure cut-off valve 18, and the pressure is monitored by a confining pressure sensor 19. A balancing valve 20 is provided outside the upstream vacuum cut-off valve 16 and the downstream vacuum cut-off valve 17, and pressure sensors 21 are provided at both ends of the balancing valve 20.

[0069] A buffer container 23 is provided on the back pressure pipeline 5 connected to the main pipeline 1 through a back pressure valve 22. The on and off of the buffer container 23 driven by a back pressure pump 24 is controlled by a back pressure stop valve 25, and the pressure is monitored by a back pressure sensor 26.

[0070] A gas concentration sensor 27 is provided in the gas-liquid separation bottle 6, and the outlet is connected to a balance 28;

[0071] In addition, on the main pipeline 1: an upstream stop valve 29 is provided between the filter pipeline 3 and the reversing valve 8, and a downstream stop valve 30 is provided between the balancing valve 19 and the back pressure valve 22;

[0072] The piston container 2 and the filter pipeline 3 both have a drain valve 31 .

[0073] The main structure of the clamp 4 involved in this embodiment is as follows Figure 2As shown, it includes a cylinder 40, a plug 41, a confining pressure inlet 42, a confining pressure outlet 43, a clamping chamber 44, an adjusting pressure cap 45, a silicone heat shrink tube 46, a rubber sleeve 47 and a venting stop valve 48;

[0074] Both ends of the cylinder 40 are provided with plugs 41, the middle side wall is provided with a confining pressure inlet 42 and a confining pressure outlet 43, and the hollow part forms a clamping chamber 44;

[0075] A core sample 100 is arranged between the plug 41 with the adjusting pressure cap 45, and the outer sides of the plug 41 and the core sample 100 are wrapped with a silicone heat shrink tube 46, and a rubber sleeve 47 is arranged on the outer side of the silicone heat shrink tube 46;

[0076] The confining pressure inlet 42 and the confining pressure outlet 43 are connected to the clamping chamber 44, and a venting stop valve 48 is provided at the confining pressure outlet 43;

[0077] Among them, the silicone heat shrink tube 46 can prevent CO 2 Corrosion clamping chamber 44 and rubber sleeve 47.

[0078] The connections involved in this embodiment are all sealed with a pan seal, and the material of the connecting pipeline is polyethylene terephthalate (PET) to solve the problem of CO 2 Corrosion problem.

[0079] The gas-liquid separation bottle 6 involved in this embodiment is used to separate CO 2 With displacement fluid, CO 2 The gas concentration is measured by a gas concentration sensor 27 and the displacement fluid is measured by a balance 28;

[0080] The reversing valve 8 is a three-way single-opening valve. When the reversing valve 8 is in the first gear position, the piston container 2 and the CO 2 The gas cylinder 9 is connected. When the reversing valve 8 is in the second gear, the piston container 2 is connected with the He gas cylinder 10, so that the displacement experiment and the overburden permeability experiment are carried out alternately without affecting each other.

[0081] Embodiment 2:

[0082] The carbon sealing storage layer ScCO involved in this embodiment 2 The specific process steps of the dissolution breakthrough mechanism and permeability evolution experimental device for rock displacement testing are as follows:

[0083] A1. Packaging core

[0084] First, a core with a diameter of 25 mm and a length of 30 mm was placed at 60° C. and dried for 24 hours, then placed in a vacuum saturation device and vacuumed for 8 hours and saturated for 4 hours using a pressure of 13 MPa to obtain a core sample 100, wherein the saturated solvent is formation water;

[0085] Then, the silicone heat shrink tube 46 is put on the outside of the plug 41 and the core sample 100, and the silicone heat shrink tube 46 is heated by a heat gun to shrink and wrap the plug 41 and the core sample 100;

[0086] Finally, the plug 41 wrapped with the silicone heat shrink tube 46 and the core sample 100 are placed in the rubber sleeve 47, placed in the clamping chamber 44 of the cylinder 40, and the adjusting pressure cap 45 is screwed to press the plug 41 and the core sample 100 tightly, and the core sample 100 is encapsulated in the clamp 4;

[0087] A2. Apply confining pressure

[0088] Apply confining pressure to the clamp 4 through the confining pressure pump 15. When fluid flows out of the vent stop valve 48, close the vent stop valve 48 and continue to apply confining pressure to 10 MPa.

[0089] A3. Vacuuming

[0090] First, close the upstream vacuum shut-off valve 16, the downstream vacuum shut-off valve 17 and the downstream shut-off valve 30;

[0091] Then, open the vacuum stop valve 11;

[0092] Finally, the vacuum pump 13 is turned on to perform vacuuming;

[0093] A4. Apply back pressure

[0094] Turn on the back pressure pump 24 to apply back pressure to the back pressure port of the back pressure valve 22 through the buffer container 23;

[0095] A5. Displacement experiment

[0096] First, the ambient temperature was set to 35°C, stabilized for 3 hours, and the vacuum shut-off valve 11, the upstream vacuum shut-off valve 16, and the balancing valve 20 were closed;

[0097] Then, open the upstream stop valve 29 and the CO2 gas cylinder 9, adjust the reversing valve 8 to the first gear position, connect the CO2 gas cylinder 9 to the piston container 2, and inject CO2 gas into the piston container 2;

[0098] Finally, the internal temperature of the piston container 2 is raised to 31.25°C, the constant pressure power pump 7 is turned on to raise the pressure of the CO2 gas to 7.38MPa, stabilized for 0.5-1h, and the upstream vacuum stop valve 16 is opened for pressure displacement;

[0099] A6. Collecting Data

[0100] Collect data from the confining pressure sensor 19, the pressure sensor 21, the back pressure sensor 26, the gas concentration sensor 27 and the balance 28, and analyze the collected data;

[0101] A7. Pressure relief

[0102] First, the pressure of the constant pressure power pump 7 is reduced to zero, and then the pressure of the back pressure pump 24 is reduced to zero.

[0103] Embodiment 3:

[0104] The carbon sealing storage layer ScCO involved in this embodiment 2 The dissolution breakthrough mechanism and permeability evolution experimental device conducts a pressure permeability test after the displacement test. The specific process steps are as follows:

[0105] B1. Vacuuming

[0106] First, close the downstream stop valve 30;

[0107] Then, open the vacuum stop valve 11, the upstream vacuum stop valve 16, the upstream stop valve 29, the downstream vacuum stop valve 17 and the balance valve 20;

[0108] Finally, the vacuum pump 13 is turned on to perform vacuuming;

[0109] B2. Apply confining pressure

[0110] Apply confining pressure to the clamp 4 through the confining pressure pump 15. When fluid flows out from the vent stop valve 48, close the vent stop valve 48 and continue to apply confining pressure to the set pressure.

[0111] B3. Overburden permeability test

[0112] First, close the vacuum stop valve 11;

[0113] Then, the He gas cylinder 10 is opened, and the reversing valve 8 is adjusted to the second gear position, so that the He gas cylinder 10 is connected to the piston container 2, and He gas is injected into the piston container 2;

[0114] Finally, the constant pressure power pump 7 is turned on to pressurize the He gas. When the pressure measured by the pressure sensor 21 is the first preset value, the constant pressure power pump 7 is kept at the first preset pressure and balanced for a set period of time, and then the upstream vacuum shut-off valve 16 and the balance valve 20 are closed. After the constant pressure power pump 7 continues to pressurize to the second preset value, the upstream shut-off valve 29 is closed, and the upstream vacuum shut-off valve 16 is opened for testing.

[0115] B4. Collecting Data

[0116] Collect data from the confining pressure sensor 19 and the pressure sensor 21, and based on the collected data, use the dimensionless pressure difference formula: Calculate the effective gas permeability:

[0117] Where: P 1 (t) is the inlet pressure of the clamp 4, P2 (t) is the outlet pressure of the clamp 4, ΔP(t) is the pulse pressure (pressure difference between the two pressure sensors 21);

[0118] C is the unit conversion factor, m 1 = ln(ΔP D )-t curve straight line segment slope, μ g is the viscosity of the gas, L is the length of the core sample 100, fz is the correction factor of the gas compressibility coefficient, f 1 is the mass flow correction factor, A is the cross-sectional area of ​​the core sample 100, and p m is the average pore pressure, V 1 is the volume of the pipeline between the inlet of the holder 4 and the upstream stop valve 29, V 2 is the volume of the pipeline between the outlet of the holder 4 and the downstream stop valve 30;

[0119] The subscript o indicates the initial moment;

[0120] B5. Pressure relief

[0121] First, the pressure of the constant pressure power pump 7 is reduced to zero, and then the pressure of the confining pressure pump 15 is reduced to zero.

Claims

1. An experimental device for the ScCO2 dissolution breakthrough mechanism and permeability evolution of a carbon-sealed storage layer, characterized in that: The main structure includes a piston container, a filter pipeline, a clamp, a back pressure pipeline and a gas-liquid separation bottle which are connected in sequence; wherein, the piston container is connected to the CO2 gas cylinder and the He gas cylinder respectively through a reversing valve, a filter is arranged on the filter pipeline, an upstream vacuum stop valve and a downstream vacuum stop valve are arranged at both ends of the clamp, and a balancing valve is arranged on the outside of the two, the back pressure pipeline is connected to the main pipeline through the back pressure valve, and a buffer container is arranged on it, a gas concentration sensor is arranged in the gas-liquid separation bottle, and the outlet is connected to a balance.

2. The experimental device for the ScCO2 dissolution breakthrough mechanism and permeability evolution of the carbon sealing storage layer according to claim 1 is characterized in that: An upstream stop valve is arranged between the filter pipeline and the reversing valve, and a downstream stop valve is arranged between the balancing valve and the back pressure valve.

3. The experimental device for the ScCO2 dissolution breakthrough mechanism and permeability evolution of the carbon sealing storage layer according to claim 1 or 2, characterized in that: The main structure of the clamp includes a cylinder and plugs arranged at both ends thereof, and a confining pressure inlet and a confining pressure outlet arranged in the middle; a core sample is arranged between the plugs, and the outside of the plugs and the core sample is wrapped with a silicone heat shrink tube, and a rubber sleeve is arranged on the outside of the silicone heat shrink tube.

4. The experimental device for the ScCO2 dissolution breakthrough mechanism and permeability evolution of the carbon sealing storage layer according to claim 3 is characterized in that: The piston container, filter pipeline, clamp, back pressure pipeline and gas-liquid separation bottle are connected through the main pipeline; the piston container is driven by a constant pressure power pump; the on-off of the filter pipeline is controlled by a vacuum stop valve, and the filter with a vacuum gauge inside is driven by the vacuum pump; the clamp is driven by a confining pressure pump, the on-off of the confining pressure pump is controlled by the confining pressure stop valve, and the pressure is monitored by a confining pressure sensor; pressure sensors are provided at both ends of the balancing valve; the buffer container is driven by a back pressure pump, the on-off is controlled by the back pressure stop valve, and the pressure is monitored by the back pressure sensor; the plug has an adjustable pressure cap to limit the movement of the core sample; a vent stop valve is provided at the confining pressure outlet.

5. The experimental device for ScCO2 dissolution breakthrough mechanism and permeability evolution of carbon sealing storage layer according to claim 3 is characterized in that: The back pressure valve establishes a set pressure difference at the outlet and inlet of the gripper according to experimental needs: During the process of the back pressure pump loading the set pressure on the back pressure port of the back pressure valve, when the back pressure valve inlet pressure is greater than or equal to the back pressure valve back pressure port loading pressure, the back pressure valve inlet pressure breaks through the back pressure valve, causing the fluid to flow in from the back pressure valve inlet and out from the back pressure valve outlet; When the back-pressure pump loads the back-pressure port of the back-pressure valve to the set pressure, the saturated fluid in the pipeline connecting the clamp outlet with the downstream vacuum shut-off valve, the downstream pressure sensor, the downstream shut-off valve and the back-pressure valve, and the saturated fluid in the capillary connected with the back-pressure valve outlet with the gas-liquid separation bottle and the balance are used to accurately calculate the displacement fluid.

6. The experimental device for ScCO2 dissolution breakthrough mechanism and permeability evolution of carbon sealing storage layer according to claim 5, characterized in that: Both the piston container and the filter line have drain valves.

7. The experimental device for ScCO2 dissolution breakthrough mechanism and permeability evolution of carbon sealing storage layer according to claim 3, characterized in that: The specific process steps for rock displacement testing are as follows: A1. Packaging core First, the core is saturated with formation water to obtain a core sample; Then, wrap the silicone heat shrink tubing tightly around the outside of the plug and the core sample; Finally, put it into a rubber sleeve and place it in the cylinder; A2. Apply confining pressure Apply confining pressure to the holder. When fluid flows out of the vent stop valve, close the vent stop valve and continue to apply confining pressure to the set value. A3. Vacuuming First, close the upstream vacuum stop valve, the downstream vacuum stop valve, and the downstream stop valve; Then, open the vacuum shut-off valve; Finally, turn on the vacuum pump to draw a vacuum; A4. Apply back pressure Turn on the back pressure pump to apply back pressure to the back pressure port of the back pressure valve; A5. Displacement experiment First, close the vacuum shut-off valve, the upstream vacuum shut-off valve, and the balancing valve; Then, open the upstream stop valve and the CO2 gas cylinder, adjust the reversing valve to connect the CO2 gas cylinder with the piston container, and inject CO2 gas into the piston container; Finally, the internal temperature of the piston container is raised to the set value, the constant pressure power pump is turned on to raise the pressure of the CO2 gas to the set value, and the upstream vacuum stop valve is opened for pressure displacement; A6. Collect data Collect data from the confining pressure sensor, pressure sensor, back pressure sensor, gas concentration sensor and balance. When ScCO2 breaks through, record the breakthrough time and breakthrough pressure, calculate the ScCO2 breakthrough speed, and monitor the overflow of CO2 gas.

8. The experimental device for ScCO2 dissolution breakthrough mechanism and permeability evolution of carbon sealing storage layer according to claim 3, characterized in that: The specific process steps for implementing the overburden permeability test method are as follows: B1. Vacuuming First, close the downstream stop valve; Then, open the vacuum stop valve, the upstream vacuum stop valve, the upstream stop valve, the downstream vacuum stop valve and the balancing valve; Finally, turn on the vacuum pump to draw a vacuum; B2. Apply confining pressure Apply confining pressure to the holder. When fluid flows out of the vent stop valve, close the vent stop valve and continue to apply confining pressure to the set pressure. B3. Overburden permeability test First, close the vacuum shutoff valve; Then, open the He gas cylinder, adjust the reversing valve to connect the He gas cylinder with the piston container, and inject He gas into the piston container; Finally, the constant pressure power pump is turned on to pressurize the He gas. When the pressure measured by the pressure sensor is the first preset value, the constant pressure power pump is kept at the first preset value pressure and balanced for a set period of time, and then the upstream vacuum shut-off valve and the balance valve are closed. After the constant pressure power pump continues to pressurize to the second preset value, the upstream shut-off valve is closed, and the upstream vacuum shut-off valve is opened for testing. B4. Collecting Data The data from the confining pressure sensor and the pressure sensor are collected, and the effective gas permeability is calculated based on the collected data.

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