Simulation experiment device and method for co2 displacement and storage in natural gas reservoir

Abstract

The application relates to the technical field of natural gas exploitation, and discloses a CO2 injection and storage simulation experiment device and method for natural gas reservoirs. The CO2 injection and storage simulation experiment device for natural gas reservoirs comprises a bottom water natural gas reservoir physical simulation system, a production horizontal well system, a resistivity monitoring system, a metering and analyzing system and a CO2 injection system. The CO2 injection and storage simulation experiment device and method for natural gas reservoirs can monitor the resistivity changes of each point of the gas reservoir in real time, and the water invasion pattern and dynamic change rule of the gas reservoir can be obtained through the resistivity change rule. Meanwhile, the gas component is measured and analyzed through a chromatograph, and the gas production rate is monitored in real time, so that the CO2 injection can be quantified to improve the recovery degree of the natural gas and the storage amount after the CO2 injection, the well pattern arrangement can be optimized, the injection and production speed can be optimized, and the injection and production amount can be optimized, so that the production guidance can be provided for the CO2 injection and storage of the natural gas reservoirs.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of natural gas exploitation, and particularly relates to a CO2 injection and storage simulation experiment device and method for natural gas reservoirs. BACKGROUND

[0002] For gas reservoirs in the middle and late stages of development, water breakthrough caused by edge water or bottom water is one of the important factors restricting the development of gas reservoirs. With the continuous production of natural gas in the gas reservoir, the pressure of the gas reservoir gradually decreases, at which time the edge and bottom water will gradually invade the gas reservoir under the action of pressure difference, and gradually push to the bottom of the production well to cause bottom hole liquid loading, which seriously damages the productivity of the gas well. A large amount of natural gas is stranded underground, which seriously threatens the recovery efficiency of the gas reservoir. At this time, injecting carbon dioxide into the gas reservoir can effectively supplement the formation energy, thereby effectively inhibiting water invasion. In addition, the injected carbon dioxide can displace and displace the remaining natural gas in the formation, thereby effectively increasing the production of remaining gas and improving the overall recovery efficiency of the gas reservoir. After injecting carbon dioxide into the formation, most of the carbon dioxide will be stranded in the gas reservoir, thereby effectively achieving the storage of carbon dioxide. The currently disclosed technology lacks a physical simulation characterization technology for carbon dioxide displacement and storage in gas reservoirs.

[0003] Most of the existing natural gas reservoir simulation experiments are mainly carried out on cores, and there is no simulation device and method for CO2 injection. For example, the published CN202210563763.1 invention patent application discloses a simulation experiment device based on gas reservoir step-by-step pressure reduction exploitation, which can carry out multiple small core experiments; and for example, the CN202410051231.9 invention patent application discloses a high-temperature and high-pressure water-bearing gas reservoir CO2 injection water invasion inhibition micro-visualization experiment device and method, which carries out experiments by preparing etching models by replicating core casting thin section pore structures, and studies the water invasion inhibition process from a two-dimensional plane perspective.

[0004] The existing technology cannot characterize the plane and longitudinal morphology of water invasion when CO2 is injected into the gas reservoir, and cannot simultaneously describe the displacement and storage processes. SUMMARY

[0005] The application provides a CO2 injection and storage simulation experiment device and method for natural gas reservoirs, which can realize physical simulation of rigid water drive or elastic water drive development of natural gas reservoirs with edge water or bottom water and simulation experiment of CO2 injection and storage in the middle and late stages of gas reservoir development.

[0006] To achieve the above-mentioned purpose, the CO2 injection and storage simulation experiment device for natural gas reservoirs comprises a bottom water natural gas reservoir physical simulation system, a production horizontal well system, a resistivity monitoring system, a metering and analyzing system, and a CO2 injection system.

[0007] The bottom water natural gas reservoir simulation system comprises an ISCO pump 1, an intermediate container 1 for containing simulated formation water and bottom water, a six-way valve 1, a pressure gauge 1, a simulated gas cylinder, a gas flowmeter 1, a six-way valve 2, a pressure gauge 2, and a gas reservoir simulation device.

[0008] The production horizontal well system comprises several laid production horizontal wells.

[0009] The resistivity monitoring system comprises a computer, a resistivity sensor, and several resistivity monitoring probes.

[0010] The metering and analyzing system comprises a gas flowmeter 2, a six-way valve 3, an output water metering bottle, a balance, and a gas collection bag, wherein the number of the metering and analyzing system is consistent with the number of the production horizontal wells.

[0011] The CO2 injection system comprises an ISCO pump 2, an intermediate container 2, a six-way valve 4, a pressure gauge 3, a gas flowmeter 3, and an injection horizontal well.

[0012] Preferably, the intermediate container 1 and the intermediate container 2 are provided with at least three-way interfaces at the upper and lower ends, and the ISCO pump 1 and the ISCO pump 2 are respectively connected to one end of the intermediate container 1 and the intermediate container 2 through threads.

[0013] Preferably, the gas reservoir simulation device is provided with at least a three-way valve at the outer bottom, the bottom of the gas reservoir simulation device, the pressure gauge 1, and the other end of the intermediate container 1 are connected through the six-way valve 1 by threads, the bottom of the gas reservoir simulation device and the gas flowmeter 1 are connected through the three-way valve by threads, and the other end of the gas flowmeter 1, the pressure gauge 2, and the intermediate container 2 are connected through the six-way valve 2 by threads.

[0014] Preferably, the production horizontal well head is connected with the metering analysis system; the resistivity sensor is connected with a plurality of resistivity monitoring probes through wires, and the resistivity monitoring probes are arranged on the inner bottom of the gas reservoir simulation device through welding.

[0015] Preferably, the gas reservoir simulation device is made of stainless steel, has a water supply grid at the bottom and a end cap at the upper portion, and is sealed through threads.

[0016] Preferably, suitable threaded hole positions are left for wires of the production horizontal well system and the resistivity monitoring system in the upper end cap of the gas reservoir simulation device, and each hole position is connected with a corresponding component through threads and a rubber ring to realize sealing.

[0017] Preferably, in the CO2 injection system, the intermediate container two, the pressure gauge three and the gas flow meter three are connected together through the six-way valve four, and the gas flow meter three is connected with the injection horizontal well through threads.

[0018] Preferably, steel wire screens are laid at each hole position in contact with the sand filling, the mesh number of the screen is greater than the maximum mesh number of the filled sand, so as to prevent the filled sand particles from entering the holes and ensure the normal use of each component.

[0019] The application further provides a method for simulating CO2 injection and gas displacement and storage in a natural gas reservoir.

[0020] S1, gas reservoir simulation sand filling:

[0021] In the gas reservoir simulation device, a rigid development model of a bottom water gas reservoir is constructed by stratified sand filling according to the original formation pressure 35 MPa of the gas reservoir, the porosity of the sand body is from top to bottom 、 、 , and the thicknesses are h1, h2 and h3 respectively, so as to match the porosity and permeability of the gas reservoir.

[0022] S2, sand body saturated fluid:

[0023] ISCO pump one is used to inject simulated formation water into the model at a flow rate of 2 ml / min through the intermediate container one until a saturation amount of 3 PV is reached, then a gas cylinder is used to inject simulated gas CH4 at a constant pressure of 30 MP, the basic resistivity value pw is recorded, the water saturation is monitored until the irreducible water saturation Swor is reached, and the model is kept at a constant pressure of 35 MPa at the same time.

[0024] S3, rigid bottom water gas reservoir depletion development:

[0025] ISCO pump is used to keep the pressure at 35 MPa, the gas production rate and the resistivity value are recorded, and the gas reservoir recovery efficiency ERt is calculated.

[0026] S4, injecting CO2 to drive gas:

[0027] When the production well starts to produce water, the production horizontal well system is closed, CO2 is injected at a speed of 1ml / min through ISCO pump two and gas flow meter three, and the inhibition of water invasion during the CO2 injection process is monitored;

[0028] S5, continue to open the well to produce after injecting CO2:

[0029] Continue to record the gas production, resistivity value, measure the produced gas composition, calculate the gas reservoir recovery and the CO2 storage condition;

[0030] S6, draw the recovery and resistivity variation graph with cumulative gas production time at different times.

[0031] Compared with the related art, the natural gas reservoir CO2 injection and storage simulation experiment device and method provided by the application has the following beneficial effects:

[0032] The application provides a natural gas reservoir CO2 injection and storage simulation experiment device and method:

[0033] 1, water invasion law of bottom water gas reservoir development: the experimental device can realize the simulation experiment of the rigid water drive or elastic water drive development physical model of the bottom water natural gas reservoir, the resistivity change of each point of the natural gas reservoir physical simulation device is monitored in real time through the resistivity monitoring device, and the water invasion law of the gas reservoir is obtained through the resistivity change law;

[0034] 2, CO2 injection and storage effect: the experimental device simulates the injection of CO2 after development for a period of time, measures and analyzes the produced gas composition through the chromatograph, judges the influence of CO2 injection on the water drive of the gas reservoir, and judges the storage condition of the natural gas reservoir after the injection of CO2;

[0035] 3, horizontal well network optimization: through the layout of different horizontal well networks, the corresponding water invasion law and recovery can be obtained, and the best well network layout can be optimized through the comparison of experimental results. DETAILED DESCRIPTION

[0036] Figure 1 The application provides a natural gas reservoir CO2 injection and storage simulation experiment device and method:

[0037] Figure 2 It is a resistivity monitoring system detail view;

[0038] Figure 3 It is a gas reservoir simulation system plan view.

[0039] The figure mark: 1, ISCO pump one; 2, intermediate container one; 3, six-way valve one; 4, pressure gauge one; 5, simulation gas cylinder; 6, gas flowmeter one; 7, six-way valve two; 8, pressure gauge two; 9, gas reservoir simulation device; 10, water supply grid; 11, end cap; 12, production horizontal well system; 13, computer; 14, resistivity sensor; 15, resistivity monitoring probe; 16, gas flowmeter two; 17, six-way valve three; 18, output water measuring bottle; 19, balance; 20, gas collection package; 21, ISCO pump two; 22, intermediate container two; 23, six-way valve four; 24, pressure gauge three; 25, gas flowmeter three; 26, injection horizontal well. DETAILED DESCRIPTION

[0040] The application will be further described below in conjunction with the drawings and embodiments.

[0041] Please refer to Figures 1-3 , wherein, Figure 1 The schematic diagram of the natural gas reservoir CO2 injection and storage simulation experiment device provided by the application is shown in the figure; Figure 2 The detail diagram of the resistivity monitoring system is shown in the figure; Figure 3 The overhead view of the gas reservoir simulation system is shown in the figure.

[0042] The natural gas reservoir CO2 injection and storage simulation experiment device provided by the application comprises a bottom water natural gas reservoir physical simulation system, a production horizontal well system, a resistivity monitoring system, a metering and analysis system, and a CO2 injection system.

[0043] The bottom water natural gas reservoir simulation system comprises ISCO pump one 1, intermediate container one 2 for containing simulated formation water and bottom water, six-way valve one 3, pressure gauge one 4, simulation gas cylinder 5, gas flowmeter one 6, six-way valve two 7, pressure gauge two 8, and gas reservoir simulation device 9.

[0044] The gas reservoir simulation device 9 is made of stainless steel, has a water supply grid 10 at the bottom and an end cap 11 at the upper part, and is sealed by threads.

[0045] The production horizontal well system 12 comprises several laid production horizontal wells.

[0046] The resistivity monitoring system comprises a computer 13, a resistivity sensor 14, and several resistivity monitoring probes 15.

[0047] The metering and analysis system comprises gas flowmeter two 16, six-way valve three 17, output water measuring bottle 18, balance 19, and gas collection package 20, wherein the number of the metering and analysis system is consistent with the number of the production horizontal wells.

[0048] The CO2 injection system comprises ISCO pump two 21, intermediate container two 22, six-way valve four 23, pressure gauge three 24, gas flowmeter three 25, and injection horizontal well 26.

[0049] The connection mode of the above-mentioned components is that the intermediate container one 2 and the intermediate container two 22 are provided with at least three-way interfaces at the upper and lower ends, the ISCO pump one 1 and the ISCO pump two 21 are respectively connected with one end of the intermediate container one 2 and the intermediate container two 22 through threads, the gas reservoir simulation device 9 is provided with at least a three-way valve at the outer bottom, the bottom of the gas reservoir simulation device 9, the pressure gauge one 4 and the other end of the intermediate container one 2 are connected through a six-way valve one 3 by threads, the bottom of the gas reservoir simulation device 9 and the gas flow meter one 6 are connected through a three-way valve by threads, the gas flow meter one 6, the pressure gauge two 8 and the other end of the intermediate container two 22 are connected through a six-way valve two 7 by threads, the production horizontal well head is connected with the metering and analyzing system, the resistivity sensor 14 and a plurality of resistivity monitoring probes 15 are connected through wires, the resistivity monitoring probes 15 are arranged on the inner bottom of the gas reservoir simulation device 9 through welding, and the wires of the production horizontal well system 12 and the resistivity monitoring system in the upper end cover 11 of the gas reservoir simulation device 9 are left with appropriate threaded hole positions, and the hole positions and the corresponding components are connected through threads and rubber rings to realize sealing.

[0050] In the CO2 injection system, the intermediate container two 22, the pressure gauge three 24 and the gas flow meter three 25 are connected together through a six-way valve four 23 by threads, and the gas flow meter three 25 is connected with the injection horizontal well 26 through threads.

[0051] It is particularly emphasized that steel wire screens are laid in all the holes in contact with the sand filling, the mesh number of the screen is greater than the maximum mesh number of the filled sand, so as to prevent the filled sand particles from entering the holes and ensure the normal use of the components.

[0052] In addition, the application also provides a method for simulating CO2 injection and gas displacement and storage in a natural gas reservoir, which comprises the following steps: (in this embodiment, a rigid bottom water drive dry gas reservoir is taken as an example, the model and the gas reservoir are filled with sand to keep the porosity and the permeability consistent, CH4 is used as simulation gas, and formation water is used as simulation water.)

[0053] 1) gas reservoir simulation sand filling

[0054] Taking a bottom water gas reservoir with an original reservoir pressure of 35MPa and rigid development as an example, the gas reservoir simulation device 9 is filled with sand in three layers, and the production horizontal well system 12 is laid in the specified position, taking a five-point well pattern as an example (the injection horizontal well is in the middle), the gas reservoir model is a cuboid, the cross-sectional area is A (m), the porosities of the three layers of sand from top to bottom are , , , the thicknesses from top to bottom are h 1, h 2, h 3 (m), and the pore volume is .

[0055] 2) Sand saturated fluid

[0056] ① Saturation with simulated formation water. Open the middle vessel 2, and inject simulated formation water into the gas reservoir simulation device 9 through the bottom inlet of the gas reservoir simulation device 9 at a rate of 2 ml / min using ISCO pump 1 to saturate the gas reservoir simulation device 9. Stop the injection and close the bottom inlet of the gas reservoir simulation device 9 when the injection volume reaches 3 PV.

[0057] ② Saturation with simulated gas. Open the resistivity measurement system device. Measure the base resistivity value of each point before starting the gas drive p w ; open the production well system, and gas flow meter 6, inject simulated gas into the gas reservoir simulation device 9 through the bottom inlet of the gas reservoir simulation device 9 at a constant pressure of 30 MPa using simulated gas cylinder 5. Record the liquid production of the production horizontal well system 12 through the metering and analysis system V iwt (i = 1, 2, 3, 4) and gas production V igt (i = 1, 2, 3, 4) until there is no water production, stop the injection and close the production well system outlet. Measure a set of resistivity values every 1 min during the entire recording process p wt , and calculate the corresponding water saturation S wt = ( V p -∑ V iwt ) / 100 V p , to obtain the water saturation S wt corresponding to the resistivity profile. Finally, when the irreducible water saturation is reached S wor , measure a set of resistivity values p wor as the base profile for subsequent water invasion.

[0058] ③ Keep the model at a constant pressure of 35 MPa. Inject simulated gas into the gas reservoir simulation device 9 through the bottom inlet of the gas reservoir simulation device 9 at a constant pressure of 35 MPa using simulated gas cylinder 5, so that the model pressure is kept at 35 MPa, the original formation pressure p i = 35 MPa.

[0059] 3) Depletion development of a rigid bottom water gas reservoir

[0060] ① Keep the rigid bottom water gas reservoir depleting by ISCO pump 1 at 35 MPa pressure, open the outlet of the production horizontal well system 12, record the cumulative production time t, the gas production VjCH4t (j = 1, 2, 3, 4), and the resistivity value pt of each point of the resistivity monitoring system;

[0061] ② Calculate the gas reservoir recovery factor at different times t

[0062] Original geological reserves:

[0063] Wherein, S gi =1- S wor , B gi =3.447*10 -4 *( Z * T ) / p i , T =273.15+25=298.15K, Z is the natural gas deviation factor.

[0064] Recovery factor: E Rt = / G*100

[0065] 4) Inject CO2 gas

[0066] ① When the balance appears digital display, it means that the production well starts to produce water at this time, and CO2 gas injection is started. Close the production horizontal well system 12, open the gas flow meter three 25, ISCO pump two 21 to inject 1 ml / min through the injection horizontal well 26 Inject CO2 gas with a volume of V CO2in Close all the above devices after injection, measure a group of resistivity values every 1 min during the injection process, get the three-dimensional resistivity profile at the corresponding time, and observe the inhibition of water invasion during CO2 injection.

[0067] 5) Continue to open well production after CO2 injection

[0068] ① Open the outlet of the production horizontal well system 12, continue to record the cumulative production time t , the gas production V jg1t , and the resistivity value p it of each point of the resistivity monitoring system.

[0069] ​② Every 5 minutes, the gas production of 4 production wells at different times was obtained through the gas collection package, the gas component was measured by a chromatograph, and the CO2 component values at different times were recorded as H CO2jt The CH4 component values at different times were recorded as H CH4jt The coordinate point set of the CO2 and CH4 component values produced by the 4 production wells at different times can be obtained, the smooth curves of the two components changing with time are obtained by interpolation processing, the component values of the two gases at any time are obtained, and the cumulative CO2 volume produced by the 4 production wells at different times after CO2 injection is obtained by integration V CO2jt , the cumulative CH4 volume V 1CH4jt .

[0070] ③ Calculate the gas reservoir recovery factor at different times t

[0071] E Rt = / G*100

[0072] ④ Stop production until no gas is produced.

[0073] ⑤ Calculate the CO2 storage situation

[0074] The final cumulative CO2 volume produced by the 4 production wells is obtained by integration V CO2j

[0075] The CO2 storage volume is: V SCO2 = V CO2in -

[0076] 6) Draw the recovery factor and resistivity curves changing with cumulative gas production time at different times

[0077] Draw the full life cycle production dynamic curve of the rigid bottom water gas reservoir simulation device 9, draw the water influx profile, analyze the water influx change law of the rigid development of the bottom water gas reservoir, and clarify the CO2 injection inhibition effect on water influx and the CO2 storage situation.

[0078] Bound water saturation S wor Resistivity value measured at p p wor ​As the basis of subsequent water invasion profile, the resistivity value measured by the resistivity measuring point of a certain part will increase obviously when water invasion occurs, so as to determine the occurrence of water invasion. If the resistivity value of the water invasion part is obviously low during the middle and late stages of the subsequent CO2 displacement, it can be known that the CO2 displacement has an effect on the water invasion inhibition.

[0079] The resistivity points can be changed according to the experimental needs, and the resistivity changes in the horizontal and vertical directions are reflected by the values measured by the resistivity points at different times, so as to obtain a three-dimensional resistivity profile.

[0080] The ISCO pump two 21 can inject CO2 with different pressures and different volumes into the injection well 26 through the intermediate container one 2 to carry out a control test.

[0081] The above only describes the embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation, or direct or indirect application in other related technical fields, which is made by using the content of the specification and drawings of the present application, is also included in the patent protection scope of the present application.

Claims

1. A simulation experimental device for CO2 injection and burial of natural gas reservoirs, characterized in that, The system comprises a bottom water natural gas reservoir physical simulation system, a production horizontal well system, a resistivity monitoring system, a metering and analyzing system, and a CO2 injection system. The bottom water natural gas reservoir physical simulation system comprises an ISCO pump 1, an intermediate container 2 for containing simulated formation water and bottom water, a six-way valve 3, a pressure gauge 1, a simulated gas cylinder 5, a gas flowmeter 6, a six-way valve 2, a pressure gauge 2, and a gas reservoir simulation device 9. The production horizontal well system 12 comprises a plurality of laid production horizontal wells. The resistivity monitoring system comprises a computer 13, a resistivity sensor 14, and a plurality of resistivity monitoring probes 15. The metering and analyzing system comprises a gas flowmeter 2, a six-way valve 3, a produced water metering bottle 18, a balance 19, and a gas collection bag 20. The CO2 injection system comprises an ISCO pump 2, an intermediate container 2, a six-way valve 4, a pressure gauge 3, a gas flowmeter 3, and an injection horizontal well 26. The intermediate container 2 and the intermediate container 22 are each provided with at least three threaded connections at the upper and lower ends, and the ISCO pump 1 and the ISCO pump 2 are respectively connected to one end of the intermediate container 2 and the intermediate container 22 through threads. The gas reservoir simulation device 9 is provided with at least a three-way valve at the outer bottom, and the bottom of the gas reservoir simulation device 9, the pressure gauge 1, and the other end of the intermediate container 2 are connected through the six-way valve 3 by threads, the bottom of the gas reservoir simulation device 9 and the gas flowmeter 1 are connected through a three-way valve by threads, and the gas flowmeter 1, the pressure gauge 2, and the other end of the intermediate container 2 are connected through the six-way valve 2 by threads.

2. The natural gas reservoir CO2 displacement and storage simulation experiment device according to claim 1, characterized in that, The production horizontal well mouth is connected to the metering and analyzing system, the resistivity sensor 14 and the plurality of resistivity monitoring probes 15 are connected through wires, and the resistivity monitoring probes 15 are arranged at the inner bottom of the gas reservoir simulation device 9 through welding.

3. The natural gas reservoir CO2 injection displacement and storage simulation experiment device according to claim 1, characterized in that, The gas reservoir simulation device 9 is made of stainless steel, is provided with a water grid 10 at the bottom and an end cap 11 at the upper part, and is sealed by threads.

4. The natural gas reservoir CO2 injection displacement and storage simulation experiment device according to claim 1, characterized in that, The end cap 11 of the gas reservoir simulation device 9 is provided with appropriate threaded hole positions for the production horizontal well system 12 and the wires of the resistivity monitoring system, and the hole positions and the corresponding components are connected through threads and rubber rings to realize sealing.

5. The natural gas reservoir CO2 injection displacement and storage simulation experiment device according to claim 1, characterized in that, In the CO2 injection system, the intermediate container 2, the pressure gauge 3, and the gas flowmeter 3 are connected together through the six-way valve 4 by threads, and the gas flowmeter 3 and the injection horizontal well 26 are connected through threads.

6. The natural gas reservoir CO2 displacement and storage simulation experiment device according to claim 1, characterized in that, Steel wire screens are laid in each hole in contact with the sand, the mesh number of the screens is greater than the maximum mesh number of the filled sand, the filled sand particles are prevented from entering the holes, and the normal use of each component is ensured.

7. A method for simulating CO2 injection and sequestration in natural gas reservoirs, characterized in that, The method is applied to the natural gas reservoir CO2 injection displacement gas and storage simulation experiment device in any one of claims 1-6, and the method comprises the following steps: S1, gas reservoir simulation sand filling: In the gas reservoir reservoir simulation device, according to the original formation pressure 35MPa of the gas reservoir, the rigid development model of the bottom water gas reservoir is constructed by stratified sand filling, and the porosity of the sand body is from top to bottom , , , the thickness is h1, h2, h3 respectively, to match the porosity and permeability of the gas reservoir; S2, sand body saturated fluid: An intermediate container is used to inject simulated formation water at a flow rate of 2 ml / min by an ISCO pump until a saturation amount of 3 PV is reached, then a simulated gas CH4 is injected at a constant pressure of 30 MPa using a simulated gas cylinder, a basic resistivity value pw is recorded, water saturation is monitored until a bound water saturation Swor is reached, and the model is kept at a constant pressure of 35 MPa; S3, rigid bottom water gas reservoir depletion development: The pressure is kept at 35 MPa by an ISCO pump, the gas production and resistivity value are recorded, and the gas reservoir recovery ERt is calculated; S4, CO2 injection displacement gas: When the production well starts to produce water, the production horizontal well system is closed, CO2 is injected at a speed of 1 ml / min by an ISCO pump and a gas flow meter three, and the inhibition of water invasion during CO2 injection is monitored; S5, continue to open well production after CO2 injection: The gas production, resistivity value, and gas component are continuously recorded, the gas reservoir recovery and CO2 storage are calculated, and the gas reservoir recovery and CO2 storage are calculated; S6, draw the recovery and resistivity change graph with cumulative gas production time at different times.

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