Device and method for analyzing chemical water plugging recovery efficiency of edge-bottom water gas reservoir

Abstract

The invention relates to the technical field of rock core experiments of oil and gas field development, in particular to a method and device for analyzing edge-bottom water gas reservoir chemical water shutoff recovery efficiency, and the device comprises a second full-diameter rock core holder for clamping a full-diameter rock core and simulating edge-bottom water; the high-pressure gas source is connected with the first full-diameter rock core holder and is used for providing saturated natural gas for the full-diameter rock core in the first full-diameter rock core holder; the high-pressure water source is connected with the second full-diameter core holder and is used for providing saturated formation water for the full-diameter core in the second full-diameter core holder; the standard container is used for collecting and metering gas flowing out of the first full-diameter core holder in real time; the I SCO pump is used for applying confining pressure to the first full-diameter core holder and / or the second full-diameter core holder. According to the method, indoor evaluation of the effect of improving the recovery efficiency by chemical water plugging can be carried out before chemical water plugging tests of gas reservoirs at the edge and the bottom of a mine field, and a direct basis is provided for formulating a recovery efficiency improving scheme.

Description

Technical Field

[0001] The invention relates to the technical field of core experiments for oil and gas field development, and in particular to a device and method for analyzing chemical water plugging recovery efficiency of edge and bottom water gas reservoirs. Background Art

[0002] As the main reservoirs for increasing natural gas reserves and production in my country, edge and bottom water gas reservoirs generally face the problem of low gas recovery due to uneven water intrusion and water production. The average recovery rate of domestic edge and bottom water gas reservoirs is less than 40%. According to first principles, water plugging can effectively reduce the intensity and degree of water intrusion and is considered one of the important means to improve the recovery rate of edge water gas reservoirs in the future. He Dongbo, Jia Ailin, Wei Yunsheng, et al., "Theory and Key Core Technologies for Balanced Development of Conventional Natural Gas Reservoirs" [J]. Natural Gas Industry, 2023, 43(01): 76-85, mentioned that chemical water plugging can be used to optimize the water invasion sweep coefficient and improve the gas reservoir recovery rate.

[0003] In the past decade, water plugging materials have developed rapidly. Domestic and foreign scholars have developed different types of water plugging materials and established a method for evaluating the performance of plugging agents, such as Dai Caili, Feng Haishun, Jian Jiabin, etc. High-temperature resistant gel foam selective water plugging agent - suitable for water plugging and stable production in high-temperature gas reservoirs in the East China Sea gas field [J]. Natural Gas Industry, 2015, 35(03): 60-67. The authors developed a new type of high-temperature resistant selective water plugging agent and used sand filling pipes to evaluate the plugging performance and formation heterogeneity selection performance of the plugging agent. Due to the lack of supporting physical simulation methods and devices for gas reservoir water plugging and enhanced oil recovery, the effect of chemical water plugging and enhanced oil recovery cannot be evaluated and predicted in advance, which greatly limits the field application of chemical water plugging and enhanced oil recovery technology in gas reservoirs, especially edge water gas reservoirs. Summary of the Invention

[0004] The present invention aims to provide a method and apparatus for analyzing the recovery efficiency of chemical water shutoff in edge and bottom water gas reservoirs, thereby providing technical support for the development of chemical water shutoff and recovery enhancement programs for edge and bottom water gas reservoirs. To achieve the above objectives, the present invention provides the following technical solutions:

[0005] A device for analyzing the chemical water shutoff recovery efficiency of an edge-bottom water gas reservoir, comprising a high-pressure water source, a high-pressure gas source, a standard container, a first full-diameter core holder, a second full-diameter core holder, and an ISCO pump, wherein:

[0006] A first full-diameter core holder holds a full-diameter core for simulating a gas reservoir;

[0007] The second full-diameter core holder holds a full-diameter core to simulate edge-bottom water;

[0008] A high-pressure gas source is connected to the first full-diameter core holder and is used to provide saturated natural gas to the full-diameter core in the first full-diameter core holder;

[0009] a high-pressure water source connected to the second full-diameter core holder for providing saturated formation water to the full-diameter core in the second full-diameter core holder;

[0010] A standard container is used to collect and measure the gas flowing out of the first full-diameter core holder in real time;

[0011] An ISCO pump is used to apply confining pressure to the first full-diameter core holder and / or the second full-diameter core holder.

[0012] Furthermore, the device further comprises a first pressure sensor, a second pressure sensor and a third valve, wherein,

[0013] The second pressure sensor and the first pressure sensor are sequentially arranged along the outlet end of the first full-diameter core holder; a third valve is arranged between the second pressure sensor and the first pressure sensor;

[0014] The second pressure sensor is arranged at the outlet end of the first full-diameter core holder and is used to measure the pressure at the outlet end of the first full-diameter core holder;

[0015] The first pressure sensor is arranged between the standard container and the second pressure sensor, and is used to measure the pressure of the standard container;

[0016] A first valve is provided between the first pressure sensor and the standard container.

[0017] Furthermore, the high-pressure water source outlet is provided with a second valve.

[0018] Furthermore, the device further comprises a third pressure sensor and a fifth pressure sensor, wherein the third pressure sensor is used to measure the confining pressure value of the first full-diameter core holder;

[0019] The fifth pressure sensor is used to measure the confining pressure value of the second full-diameter core holder.

[0020] Furthermore, the device further comprises a fourth pressure sensor for measuring the air-water interface pressure between the first full-diameter core holder and the second full-diameter core holder;

[0021] A fourth valve is provided between the fourth pressure sensor and the first full-diameter core holder.

[0022] Furthermore, the device also includes a sixth pressure sensor for measuring water pressure.

[0023] Furthermore,

[0024] A fifth valve is provided between the sixth pressure sensor and the high-pressure water source.

[0025] Furthermore, the device further comprises a computer,

[0026] The computer is connected to the ISCO pump and is used to control the confining pressure of the ISCO pump on the first full-diameter core holder and the confining pressure of the second full-diameter core holder;

[0027] Also used to perform calculations based on recorded data.

[0028] Furthermore, the device further comprises a computer,

[0029] The computer is connected to the first pressure sensor for receiving and recording the standard container pressure;

[0030] The computer is connected to a second pressure sensor for receiving and recording the pressure at the outlet end of the first full-diameter core holder;

[0031] The computer is connected to the third pressure sensor and is used to receive and record the confining pressure of the first full-diameter core holder and control the parameters of the ISCO pump according to the received confining pressure;

[0032] The computer is connected to a fourth pressure sensor for receiving and recording the air-water interface pressure between the first full-diameter core holder and the second full-diameter core holder;

[0033] The computer is connected to the fifth pressure sensor and is used to receive and record the confining pressure of the second full-diameter core holder and control the parameters of the ISCO pump according to the received confining pressure;

[0034] The computer is connected to a sixth pressure sensor for receiving and recording water pressure.

[0035] The present invention also provides a method for analyzing the recovery efficiency of chemical water plugging in edge-bottom water gas reservoirs, the method comprising:

[0036] The first full-diameter core holder clamps a first full-diameter core, and the second full-diameter core holder clamps a second full-diameter core;

[0037] An ISCO pump applies confining pressure to the first full-diameter core and the second full-diameter core;

[0038] Simulating a gas reservoir: Using a high-pressure gas source, saturated natural gas is injected into the first full-diameter core after confining pressure is applied. The injection of saturated natural gas is stopped when the pressure in the first full-diameter core holder reaches a first threshold.

[0039] Simulating edge and bottom water: using a high-pressure water source to inject saturated formation water into the second full-diameter core, and stopping the injection of saturated formation water when the pressure in the second full-diameter core holder reaches a second threshold;

[0040] When the first full-diameter core holder and the second full-diameter core holder are fully connected, a physical simulation is performed for the edge-water gas reservoir without water blocking, and the cumulative gas production and recovery degree of the simulated gas reservoir without water blocking are calculated.

[0041] When a plugging agent is injected between the first full-diameter core holder and the second full-diameter core holder, and the first full-diameter core holder and the second full-diameter core holder are not connected or partially connected, a physical simulation is performed during water plugging of an edge-water gas reservoir to calculate and obtain the cumulative gas production and the first recovery degree during water plugging of the simulated gas reservoir;

[0042] The recovery efficiency of chemical water plugging in edge-bottom water gas reservoirs was analyzed by comparing the cumulative gas production and recovery degree without water plugging with the cumulative gas production and recovery degree with water plugging.

[0043] Furthermore, the calculation formulas for the cumulative gas production and recovery degree when there is no water plugging and / or the cumulative gas production and recovery degree when there is water plugging are as follows:

[0044] G p =10VLP1

[0045]

[0046] Where: V L Indicates the volume of the standard container; P1 indicates the pressure of the standard container; G p Indicates the cumulative gas production of the simulated gas reservoir; V p represents the first full-diameter core pore volume; S wi Indicates the water saturation of the simulated gas reservoir; B gi It represents the natural gas volume coefficient in the initial state of the simulated gas reservoir, which is determined according to the saturated natural gas pressure of the simulated gas reservoir; η represents the recovery degree of the simulated gas reservoir.

[0047] The technical effects and advantages of the present invention are as follows:

[0048] The method and device of the present invention can be used to conduct indoor evaluation of the chemical water plugging effect of improving the recovery rate before the chemical water plugging test of the edge water and bottom water gas reservoirs in the mine, providing a direct basis for the formulation of chemical water plugging to improve the recovery rate of the edge water and bottom water gas reservoirs, and has positive significance for improving the efficient development of the edge water and bottom water gas reservoirs.

[0049] The test device and method of this invention achieve the goal of evaluating the effectiveness of water shutoff for enhanced oil recovery in edge-water gas reservoirs. The device features low hardware requirements, simple operation, and reliable experimental results, enabling rapid, effective, and convenient evaluation of water shutoff for enhanced oil recovery in edge- and bottom-water gas reservoirs. The final test results also provide technical support for the development of water shutoff strategies for enhanced oil recovery in edge- and bottom-water gas reservoirs.

[0050] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 Schematic diagram of the structure of the device of the present invention;

[0052] Figure 2 This is the cumulative gas production curve of the simulation test of the present invention;

[0053] Figure 3 This is the recovery degree curve simulated by the present invention. DETAILED DESCRIPTION

[0054] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only 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 ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0055] In order to solve the deficiencies of the prior art, the present invention discloses a device for analyzing the chemical water plugging recovery efficiency of edge and bottom water gas reservoirs. Figure 1 As shown, the device includes a high-pressure water source, a high-pressure gas source, a standard container, a first full-diameter core holder, a second full-diameter core holder, an ISCO pump, a pressure sensor, a valve and a computer, wherein,

[0056] A first full-diameter core holder holds a full-diameter core for simulating a gas reservoir;

[0057] The second full-diameter core holder holds a full-diameter core to simulate edge-bottom water;

[0058] A high-pressure gas source is connected to the first full-diameter core holder and is used to provide saturated natural gas to the first full-diameter core in the first full-diameter core holder;

[0059] a high-pressure water source connected to the second full-diameter core holder for providing saturated formation water to the second full-diameter core in the second full-diameter core holder;

[0060] A standard container is used to collect and measure the gas flowing out of the first full-diameter core holder in real time;

[0061] An ISCO pump is used to apply confining pressure to the first full-diameter core holder and / or the second full-diameter core holder.

[0062] In some specific embodiments of the present invention, the pressure sensor includes a first pressure sensor, a second pressure sensor, a third pressure sensor, a fourth pressure sensor, a fifth pressure sensor and a sixth pressure sensor, wherein:

[0063] The second pressure sensor and the first pressure sensor are sequentially arranged along the outlet end of the first full-diameter core holder;

[0064] The second pressure sensor is arranged at the outlet end of the first full-diameter core holder and is used to measure the pressure at the outlet end of the first full-diameter core holder;

[0065] The first pressure sensor is arranged between the standard container and the second pressure sensor, and is used to measure the pressure of the standard container.

[0066] The third pressure sensor is used to measure the confining pressure of the first full-diameter core holder;

[0067] The fifth pressure sensor is used to measure the confining pressure of the second full-diameter core holder.

[0068] The fourth pressure sensor is disposed between the first full-diameter core holder and the second full-diameter core holder, and is used to measure the air-water interface pressure between the first full-diameter core holder and the second full-diameter core holder;

[0069] The sixth pressure sensor is used to measure water pressure.

[0070] In some specific embodiments of the present invention, the valve includes a first valve, a second valve, a third valve, a fourth valve and a fifth valve, wherein:

[0071] The first valve is set between the first pressure sensor and the standard container, and the third valve is set between the second pressure sensor and the first pressure sensor; the first valve and the third valve are opened to receive the gas flowing out of the simulated gas reservoir (the first full-diameter core holder).

[0072] The second valve is arranged at the high-pressure water source outlet and is used to control the switch of the high-pressure water source outlet.

[0073] A fourth valve is disposed between the fourth pressure sensor and the first full-diameter core holder.

[0074] The fifth valve is arranged between the sixth pressure sensor and the high-pressure water source.

[0075] The device also includes a computer,

[0076] The computer is connected to the first pressure sensor for receiving and recording the standard container pressure;

[0077] The computer is connected to a second pressure sensor for receiving and recording the pressure at the outlet end of the first full-diameter core holder;

[0078] The computer is connected to the third pressure sensor and is used to receive and record the confining pressure of the first full-diameter core holder and control the parameters of the ISCO pump according to the received confining pressure;

[0079] The computer is connected to a fourth pressure sensor for receiving and recording the air-water interface pressure between the first full-diameter core holder and the second full-diameter core holder;

[0080] The computer is connected to the fifth pressure sensor and is used to receive and record the confining pressure of the second full-diameter core holder and control the parameters of the ISCO pump according to the received confining pressure;

[0081] The computer is connected to a sixth pressure sensor for receiving and recording water pressure;

[0082] The computer is connected to the ISCO pump and is used to control the confining pressure of the ISCO pump on the first full-diameter core holder and the confining pressure of the second full-diameter core holder;

[0083] The computer is also used to record experimental data and process the experimental data according to the records.

[0084] The present invention also provides a method for analyzing the recovery efficiency of chemical water plugging in edge and bottom water gas reservoirs. The method for indoor evaluation of the effect of chemical water plugging on improving the recovery rate of edge and bottom water gas reservoirs comprises the following steps:

[0085] Step 1: Select two full-diameter cores with appropriate water saturation, and place them in the first full-diameter core holder and the second full-diameter core holder respectively. The first full-diameter core holder holds the first full-diameter core, and the second full-diameter core holder holds the second full-diameter core; and follow the Figure 1 The experimental device schematic diagram shown in the figure is connected to the experimental device and all valves are closed;

[0086] In some specific embodiments of the present invention, the full-diameter core holder is preferably made of steel, resistant to high pressure and high temperature, with a maximum pressure of 70 MPa and a maximum temperature of 150° C. The full-diameter core has a diameter of 9.5 to 10.5 cm and a length of 10 to 20 cm.

[0087] The length, diameter, water saturation, pore volume and porosity of the full-diameter core with appropriate water saturation have been obtained by other methods before testing, wherein the second full-diameter core simulates edge water and the core water saturation is 100%; the first full-diameter core simulates a gas reservoir and the core water saturation is equal to the preset water saturation.

[0088] Step 2: An ISCO pump applies confining pressure to the first full-diameter core and the second full-diameter core;

[0089] In some specific embodiments of the present invention, the confining pressure is increased by using an ISCO pump which is a computer-automatically controlled high-pressure injection pump.

[0090] In some specific embodiments of the present invention, the magnitude of the confining pressure is consistent with a preset confining pressure, and the magnitude of the confining pressure is read by a third pressure sensor and a fifth pressure sensor.

[0091] Step 3: Simulating a gas reservoir: Open the second and third valves, and use a high-pressure gas source to inject saturated natural gas into the first full-diameter core after applying confining pressure. When the pressure in the first full-diameter core holder reaches a first threshold, close the second and third valves to stop injecting saturated natural gas.

[0092] Step 4: Simulating edge and bottom water: Open the fifth valve and use a high-pressure water source to inject saturated formation water into the second full-diameter core. When the pressure in the second full-diameter core holder reaches the second threshold, close the fifth valve and stop injecting saturated formation water.

[0093] Step 5: When the first full-diameter core holder and the second full-diameter core holder are connected, a physical simulation is performed when the edge water gas reservoir is not blocked, and the cumulative gas production and recovery degree when the simulated gas reservoir is not blocked are calculated; specifically:

[0094] Fully open the first and fourth valves, and partially open the third valve to conduct a physical simulation of the edge water gas reservoir without water blocking. The physical simulation can obtain real-time pressure data. When water appears at the outlet of the first core holder, stop the experiment and close all valves. The cumulative gas production and recovery degree when the simulated gas reservoir is not blocked are calculated as follows:

[0095] Gp=10VLP1 (1);

[0096]

[0097] Where: V L - standard container volume, mL; P1- intermediate container pressure, MPa, measured by pressure sensor; G p - Cumulative gas production of simulated gas reservoir, mL; V p -Full diameter core pore volume, mL, calculated based on the core diameter, length, and porosity provided by the client; S wi -Simulated gas reservoir water saturation, f; B gi - natural gas volume coefficient in the initial state of the simulated gas reservoir, f, determined according to the saturated natural gas pressure of the simulated gas reservoir; η - the degree of recovery of the simulated gas reservoir, %.

[0098] Step 6: When a plugging agent is injected between the first full-diameter core holder and the second full-diameter core holder, and the first full-diameter core holder and the second full-diameter core holder are partially connected or disconnected, a physical simulation is performed during water plugging of an edge-water gas reservoir to calculate and obtain the cumulative gas production and the degree of recovery during water plugging of the simulated gas reservoir; specifically:

[0099] Step 601: repeating steps 3) and 4) in sequence to simulate pressurized saturation of natural gas in a gas reservoir and pressurized saturation of formation water in edge and bottom water;

[0100] Step 602: Open the fourth valve and inject a plugging agent, which includes inorganic salt plugging agents, epoxy resin plugging agents, polymer gel plugging agents, and foam plugging agents. When the amount of plugging agent injected reaches the client's requirement, stop injecting the plugging agent and close the fourth valve.

[0101] Step 603: Fully open the first and fourth valves, and partially open the third valve to perform a physical simulation of water plugging in an edge-water gas reservoir. This physical simulation can obtain real-time pressure data. When water appears at the outlet of core holder 1, the experiment is terminated and all valves are closed. The cumulative gas production and recovery degree during water plugging in the simulated gas reservoir are calculated using equations (1) and (2).

[0102] The efficiency of chemical water shutoff recovery in edge-bottom water gas reservoirs is analyzed by comparing the cumulative gas production and recovery degree when there is no water shutoff and the cumulative gas production and recovery degree when there is water shutoff. The details are as follows:

[0103] Based on the data obtained from the examples of the present invention, the curves of cumulative gas production and recovery degree with pressure change in the development of edge and bottom water gas reservoirs without water plugging and with water plugging can be obtained ( Figure 2 、 Figure 3 ), the effect of chemical water plugging on enhancing oil recovery in edge and bottom water gas reservoirs was quantitatively evaluated by comparing the cumulative gas production and recovery degree under two conditions.

[0104] The technical solution of the present invention will be further described below with reference to specific embodiments.

[0105] Step 1) Select two full-diameter cores with appropriate water saturation, place them in full-diameter core holder 1 and full-diameter core holder 2, respectively, connect the experimental device according to the experimental device schematic, and close all valves;

[0106] Step 101) The full diameter core has a diameter of 9.5 to 10.5 cm and a length of 10 to 20 cm;

[0107] Step 102) The length, diameter, water saturation, pore volume, and porosity of the full-diameter core with the appropriate water saturation were determined by other methods prior to testing. The second full-diameter core simulated an edge-water porous medium and had a water saturation of 100%. The first full-diameter core simulated a gas reservoir and had a water saturation equal to the client's required water saturation. In this simulation test, the first full-diameter core had a diameter of 10 cm, a length of 14.4 cm, a pore volume of 143.27 mL, a porosity of 12.7%, a water saturation of 32%, and saturated natural gas of 20,382 mL. The second full-diameter core had a diameter of 10 cm, a length of 18.2 cm, a pore volume of 182.75 mL, a porosity of 12.8%, and a water saturation of 100%.

[0108] Step 2) Using an ISCO pump, confining pressure is applied to the first full-diameter core holder and the second full-diameter core holder in sequence.

[0109] Step 201) The full-diameter core holder is made of steel and has high pressure and high temperature resistance, with a maximum pressure of 70 MPa and a maximum temperature of 150°C.

[0110] In step 202), the confining pressure is increased by using an ISCO pump which is a computer-controlled high-pressure injection pump.

[0111] Step 203) The confining pressure is consistent with the confining pressure required by the client, and the confining pressure is read by the third and fifth pressure sensors. The confining pressure in this simulation test is 40 MPa.

[0112] Step 3) Open the second and third valves to pressurize and saturate the first full-diameter core with natural gas using a high-pressure gas source. When the saturation pressure of the full-diameter core holder 1 (obtained by testing with pressure sensor 2) reaches the saturation pressure required by the client, close the second and third valves. The pressurized saturated natural gas pressure in this simulation test is 30 MPa.

[0113] Step 4) Open the fifth valve to pressurize the second full-diameter core with formation water using a high-pressure water source. Close the fifth valve when the saturation pressure in the second full-diameter core holder reaches the saturation pressure required by the client. The pressurized saturated formation water pressure in this simulation test is also 30 MPa.

[0114] Step 5) Fully open the first and fourth valves, and partially open the third valve to conduct a physical simulation of the edge-water gas reservoir without water blocking. This physical simulation can obtain real-time pressure data. The experiment is terminated when water appears at the outlet of the first core holder, and all valves are closed. The standard container volume for this simulation test is 1000 mL. The cumulative gas production and recovery degree when the simulated gas reservoir is not blocked are calculated using the following formula:

[0115] G p=10000P1 (3);

[0116]

[0117] Where: P1-intermediate container pressure, MPa, measured by pressure sensor; G p - Cumulative gas production of simulated gas reservoir, mL; η - Recovery degree of simulated gas reservoir, %.

[0118] In this simulation test, when there is no water plugging, the final cumulative gas production is 12280mL, and the recovery rate is 60.3%.

[0119] Step 6) repeating steps 3) and 4) in sequence to simulate the pressurized saturation of natural gas in the gas reservoir and the pressurized saturation of formation water in the edge and bottom water;

[0120] Step 7) Open the fourth valve and inject the plugging agent provided by the client. When the injection volume reaches the client's requirement, stop injecting the plugging agent and close the fourth valve. The plugging agent used in this simulation test is a gel-type plugging agent with an injection volume of 54 mL.

[0121] Step 8) Fully open the first valve and the fourth valve, and partially open the third valve to conduct a physical simulation of water blocking in the edge water gas reservoir. The physical simulation can obtain real-time pressure data. When water appears at the outlet of the first core holder, stop the experiment and close all valves. The calculation formulas for the cumulative gas production and recovery degree when simulating water blocking in the gas reservoir are as shown in formulas (3) and (4). The test results are as follows: Figure 2 and Figure 3 It can be seen that in this simulation test, the bottom hole pressure when the water plugging development was abandoned was 8.06MPa, the cumulative gas production was 16080mL, and the final recovery rate was 78.9%; the bottom hole pressure when the development was abandoned without water plugging was 17.52MPa, the cumulative gas production was 12280mL, and the final recovery rate was 60.3%. The bottom hole pressure of the abandoned gas reservoir with water plugging development was lower, and the final recovery rate was also higher. The final recovery rate of the water plugging development was increased by 18.6 percentage points compared with the development without water plugging, and the water plugging had a good effect in improving the recovery rate.

[0122] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A device for analyzing the chemical water shutoff recovery efficiency of edge and bottom water gas reservoirs, characterized in that: The device includes a high-pressure water source, a high-pressure gas source, a standard container, a first full-diameter core holder, a second full-diameter core holder and an ISCO pump, wherein: A first full-diameter core holder holds a full-diameter core for simulating a gas reservoir; The second full-diameter core holder holds a full-diameter core to simulate edge-bottom water; A high-pressure gas source is connected to the first full-diameter core holder and is used to provide saturated natural gas to the full-diameter core in the first full-diameter core holder; a high-pressure water source connected to the second full-diameter core holder for providing saturated formation water to the full-diameter core in the second full-diameter core holder; A standard container is used to collect and measure the gas flowing out of the first full-diameter core holder in real time; An ISCO pump is used to apply confining pressure to the first full-diameter core holder and / or the second full-diameter core holder.

2. The device for analyzing the chemical water shutoff recovery efficiency of edge and bottom water gas reservoirs according to claim 1, characterized in that: The device further comprises a first pressure sensor, a second pressure sensor and a third valve, wherein, The second pressure sensor and the first pressure sensor are sequentially arranged along the outlet end of the first full-diameter core holder; a third valve is arranged between the second pressure sensor and the first pressure sensor; The second pressure sensor is arranged at the outlet end of the first full-diameter core holder and is used to measure the pressure at the outlet end of the first full-diameter core holder; The first pressure sensor is arranged between the standard container and the second pressure sensor, and is used to measure the pressure of the standard container; A first valve is provided between the first pressure sensor and the standard container.

3. The device for analyzing chemical water shutoff recovery efficiency of edge and bottom water gas reservoirs according to claim 2, characterized in that: The high-pressure water source outlet is provided with a second valve.

4. The device for analyzing chemical water shutoff recovery efficiency of edge and bottom water gas reservoirs according to claim 2, characterized in that: The device further comprises a third pressure sensor and a fifth pressure sensor, The third pressure sensor is used to measure the confining pressure of the first full-diameter core holder; The fifth pressure sensor is used to measure the confining pressure of the second full-diameter core holder.

5. The device for analyzing chemical water shutoff recovery efficiency of edge and bottom water gas reservoirs according to claim 4, characterized in that: The apparatus further includes a fourth pressure sensor for measuring the air-water interface pressure between the first full-diameter core holder and the second full-diameter core holder; A fourth valve is provided between the fourth pressure sensor and the first full-diameter core holder.

6. The device for analyzing chemical water shutoff recovery efficiency of edge and bottom water gas reservoirs according to claim 5, characterized in that: The device further comprises a sixth pressure sensor for measuring the pressure of the water body.

7. The device for analyzing chemical water shutoff recovery efficiency of edge and bottom water gas reservoirs according to claim 6, characterized in that: A fifth valve is provided between the sixth pressure sensor and the high-pressure water source.

8. The device for analyzing chemical water shutoff recovery efficiency of edge and bottom water gas reservoirs according to any one of claims 1 to 7, characterized in that: The device also includes a computer, The computer is connected to the ISCO pump and is used to control the confining pressure value of the ISCO pump on the first full-diameter core holder and the confining pressure value of the second full-diameter core holder; The computer is also used to perform calculations based on the recorded data.

9. The device for analyzing chemical water shutoff recovery efficiency of edge and bottom water gas reservoirs according to claim 6, characterized in that: The device also includes a computer, The computer is connected to the first pressure sensor for receiving and recording the standard container pressure; The computer is connected to a second pressure sensor for receiving and recording the pressure at the outlet end of the first full-diameter core holder; The computer is connected to the third pressure sensor, and is used to receive and record the confining pressure value of the first full-diameter core holder, and control the parameters of the ISCO pump according to the received confining pressure value; The computer is connected to a fourth pressure sensor for receiving and recording the air-water interface pressure between the first full-diameter core holder and the second full-diameter core holder; The computer is connected to the fifth pressure sensor, and is used to receive and record the pressure value of the second full-diameter core holder, and control the parameters of the ISCO pump according to the received confining pressure value; The computer is connected to a sixth pressure sensor for receiving and recording water pressure.

10. A method for analyzing the recovery efficiency of chemical water shutoff in edge-bottom water gas reservoirs, characterized in that: The method comprises, The first full-diameter core holder clamps a first full-diameter core, and the second full-diameter core holder clamps a second full-diameter core; An ISCO pump applies confining pressure to the first full-diameter core and the second full-diameter core; Simulating a gas reservoir: Using a high-pressure gas source, saturated natural gas is injected into the first full-diameter core after confining pressure is applied. The injection of saturated natural gas is stopped when the pressure in the first full-diameter core holder reaches a first threshold. Simulating edge and bottom water: using a high-pressure water source to inject saturated formation water into the second full-diameter core, and stopping the injection of saturated formation water when the pressure in the second full-diameter core holder reaches a second threshold; When the first full-diameter core holder and the second full-diameter core holder are fully connected, a physical simulation is performed for the edge-water gas reservoir without water blocking, and the cumulative gas production and recovery degree of the simulated gas reservoir without water blocking are calculated. When a plugging agent is injected between the first full-diameter core holder and the second full-diameter core holder, and the first full-diameter core holder and the second full-diameter core holder are not connected or partially connected, a physical simulation is performed during water plugging of an edge-water gas reservoir to calculate and obtain the cumulative gas production and the first recovery degree during water plugging of the simulated gas reservoir; The recovery efficiency of chemical water plugging in edge-bottom water gas reservoirs was analyzed by comparing the cumulative gas production and recovery degree without water plugging with the cumulative gas production and recovery degree with water plugging.

11. The method for analyzing the recovery efficiency of chemical water shutoff in edge-bottom water gas reservoirs according to claim 10, characterized in that: The calculation formulas for the cumulative gas production and recovery degree when there is no water plugging and / or the cumulative gas production and recovery degree when there is water plugging are as follows: G p =10V L P1; Where: V L Indicates the volume of the standard container; P1 indicates the pressure of the standard container; G p Indicates the cumulative gas production of the simulated gas reservoir; V p represents the first full-diameter core pore volume; S wi Indicates the water saturation of the simulated gas reservoir; B gi represents the natural gas volume coefficient in the initial state of the simulated gas reservoir; η represents the recovery degree of the simulated gas reservoir.

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