Method for rapidly evaluating gas reservoir drainage capacity of different injection-production cycles of aquifer type gas reservoir

Abstract

The present application relates to natural gas storage technical field, specifically relates to a kind of method for rapidly evaluating aquifer type gas storage different injection-production cycle gas reservoir drainage volume.The method includes the following steps: according to the development dynamic analysis data or well test analysis data of gas reservoir favorable trap, obtain the cumulative water influx of gas reservoir at a moment;Obtain gas reservoir water influx coefficient;According to the upper and lower limit pressure of gas reservoir operation and the original formation pressure of gas reservoir trap, obtain the pressure variation coefficient of high pressure cycle of gas reservoir and the pressure variation coefficient of low pressure cycle;According to the water influx coefficient of gas reservoir, the pressure variation coefficient of high pressure cycle of gas reservoir and the pressure variation coefficient of low pressure cycle, establish aquifer type gas storage different injection-production cycle gas reservoir drainage volume relationship model, obtain different cycle gas reservoir drainage volume.The method of the present application can quickly and simply and accurately obtain aquifer type gas storage drainage volume, which provides basis for aquifer type gas storage design and production operation.

Description

Technical Field

[0001] This invention relates to the field of natural gas storage technology, and specifically to a method for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles. Background Technology

[0002] Underground gas storage facilities are an effective means of seasonal peak shaving, emergency peak shaving, and strategic energy reserves. Utilizing aquifers to renovate gas storage facilities can effectively break the limitation of gas storage construction revolving around oil and gas production areas, allowing for construction near high-consumption natural gas regions. Aquifer-type gas storage facilities require gas injection exceeding the original formation pressure to drive away water and form storage capacity. However, the pressure-bearing capacity of the trap is limited, necessitating the design of drainage wells to remove water from the trap and achieve pressure reduction and drainage. Accurately evaluating the drainage volume of aquifer-type gas storage facilities during different injection and production cycles remains a challenging technical problem for researchers.

[0003] Developed countries' underground gas storage facilities provide peak-shaving and emergency reserves that account for 17-27% of annual consumption. China's gas storage capacity lags significantly behind that of other countries. At the end of 2018, my country's completed underground gas storage facilities had a working capacity of 10.5 billion cubic meters, accounting for 3.8% of the country's natural gas consumption. This is far below the internationally recognized 10% storage capacity and is insufficient to meet peak-shaving demands during the winter. As of 2019, my country had 25 completed gas storage facilities with a designed working capacity of 18.6 billion cubic meters and an effective working capacity of 8.5 billion cubic meters, mainly concentrated in North China. With my country's ever-increasing demand for natural gas, the domestic expectation for peak-shaving gas volume exceeds the total working capacity of existing depleted oil and gas reservoir and salt cavern type underground gas storage facilities by 179%, indicating a significant shortfall in peak-shaving capacity. Currently, most domestic gas storage facilities are built on depleted oil and gas reservoirs, and the initial capacity assessments often utilize natural gas reserves calculated from crude oil and gas reservoirs. Near major cities and industrial centers with the highest peak demand, there aren't always suitable depleted oil and gas reservoirs or salt cavern structures to be converted into underground gas storage facilities. Long-distance pipeline transportation also places high demands on safe gas supply. However, aquifer structures can always be found. In such cases, utilizing aquifer structures to construct underground gas storage facilities becomes the preferred solution. Currently, most underground gas storage facilities built near major cities and industrial centers worldwide are aquifer-type underground gas storage facilities.

[0004] Currently, there are 86 operational aquifer gas storage facilities worldwide, accounting for 13.7% of all types of gas storage facilities globally, with a total working gas volume of 41.218 billion cubic meters, representing 14.57% of the total working gas volume of global gas storage facilities. These 86 aquifer gas storage facilities are mainly distributed in North America, Europe, and Russia, with 51 in the United States, 12 in France, and 7 each in Germany and Russia. Other countries have fewer facilities. There are no precedents for constructing gas storage facilities using aquifers in China; all projects are in the preliminary research stage, and there is a lack of methods for rapidly and accurately evaluating the drainage volume of drainage wells in aquifer gas storage facilities.

[0005] CN108625823A discloses a method for determining the capacity of a gas storage facility. The method includes the following steps: establishing a formation pressure model based on the real-time radius of the gas layer in the gas storage facility; establishing a bottom-hole flowing pressure model based on the effective permeability of the gas storage facility and the gas layer skin coefficient; establishing a wellhead oil pressure model and a gas injection model for the gas storage facility based on the formation pressure model and the bottom-hole flowing pressure model; and determining the capacity of the gas storage facility based on the wellhead oil pressure model and the gas injection model.

[0006] CN113008752B discloses a method for determining the effective pore volume in oil reservoir-type gas storage capacity calculation. The method includes the following steps: S1, constructing a two-dimensional large-scale planar rock slab model and measuring gas permeability; S2, filling the planar rock slab and saturating it with experimental fluid to establish bound water saturation; S3, conducting multiple rounds of gas injection and production experiments using a two-dimensional sand-filled model; S4, applying the planar radial flow formula to perform calculations, analyzing the changes in production capacity during the experiment, and optimizing the calculation and analysis model; S5, calculating the oil saturation based on the degree of recovery, and constructing a relative permeability curve based on the calculated effective permeability.

[0007] CN104484550B discloses a method and apparatus for obtaining the storage capacity of a gas storage facility converted from a water-flooded gas reservoir. The method includes: obtaining the relationship between the gas-water interface of the gas storage facility and the reservoir pressure; dividing the pore volume occupied by the dynamic gas reserves of the gas storage facility into three gas storage fluid regions: a gas region, a gas-water interaction region, and a water region, based on the relationship, and calculating the pore volume contribution of each gas storage fluid region to the dynamic gas reserves; deducting the pore volume in each gas storage fluid region that cannot be used for gas storage based on the pore volume contribution of each gas storage fluid region to the dynamic gas reserves; and calculating the storage capacity of the gas storage facility based on the deduction of the pore volume in each gas storage fluid region that cannot be used for gas storage. Summary of the Invention

[0008] The main objective of this invention is to provide a method for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles. This method can quickly, easily, and accurately obtain the liquid discharge volume of an aquifer-type gas storage facility, providing a basis for the design and operation of such facilities.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] In a first aspect, the present invention provides a method for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles, the method comprising the following steps:

[0011] Based on the development dynamic analysis data or well test analysis data of the favorable traps of the gas storage, obtain the cumulative water intrusion of the gas storage at a certain moment; obtain the water intrusion coefficient of the gas storage.

[0012] Based on the upper and lower limit pressures of the gas storage operation and the original formation pressure of the gas storage enclosure, the pressure change coefficients of the high-pressure cycle and the low-pressure cycle of the gas storage are obtained.

[0013] Based on the water intrusion coefficient, the pressure change coefficient of the high-pressure cycle, and the pressure change coefficient of the low-pressure cycle, a model is established to determine the relationship between the liquid discharge volume of the aquifer-type gas storage in different injection and production cycles, and to obtain the liquid discharge volume of the gas storage in different cycles.

[0014] A second aspect of the present invention provides a system for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles, the system comprising:

[0015] The first calculation module is used to obtain the gas storage water intrusion coefficient;

[0016] The second calculation module is used to obtain the pressure change coefficient of the high-pressure cycle and the pressure change coefficient of the low-pressure cycle in the gas storage.

[0017] The data processing module, based on the relational model To obtain the liquid discharge volume of the gas storage in different cycles;

[0018] in, —The liquid discharge volume of the gas reservoir, , —Water intrusion coefficient, —High-pressure cycle pressure coefficient, c d —Low-pressure cycle pressure coefficient.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] The method of this invention calculates the liquid discharge volume of aquifer gas storage facilities based on the pressure change coefficients during high-pressure and low-pressure cycles and the water intrusion coefficient, yielding results with high accuracy. This invention enables the rapid, simple, and accurate acquisition of liquid discharge volume for aquifer gas storage facilities, providing a basis for the design and operation of aquifer gas storage facilities.

[0021] Compared with other methods, the method of this invention has the advantages of requiring fewer parameters, fast calculation speed, and accurate evaluation results, and solves the problem that the drainage volume of different injection and production cycles in the design and operation of aquifer gas storage facilities cannot be accurately evaluated. Attached Figure Description

[0022] Figure 1 This is a flowchart of the method for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles, as described in an embodiment of the present invention.

[0023] Figure 2 This is a schematic diagram of the high-voltage cycle and low-voltage cycle described in Embodiment 1 of the present invention;

[0024] Figure 3This is a schematic diagram of the high-voltage cycle and low-voltage cycle described in Embodiment 2 of the present invention. Detailed Implementation

[0025] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0026] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. Furthermore, it should be understood that when the terms "comprising" or "including" are used in this specification, they indicate the presence of features, steps, operations, and combinations thereof.

[0027] To address the problems described in the background art, this invention provides a method for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles. The method includes the following steps:

[0028] Based on the development dynamic analysis data or well test analysis data of the favorable traps of the gas storage, obtain the cumulative water intrusion of the gas storage at a certain moment; obtain the water intrusion coefficient of the gas storage.

[0029] Based on the upper and lower limit pressures of the gas storage operation and the original formation pressure of the gas storage enclosure, the pressure change coefficients of the high-pressure cycle and the low-pressure cycle of the gas storage are obtained.

[0030] Based on the water intrusion coefficient, the pressure change coefficient of the high-pressure cycle, and the pressure change coefficient of the low-pressure cycle, a model is established to determine the relationship between the liquid discharge volume of the aquifer-type gas storage in different injection and production cycles, and to obtain the liquid discharge volume of the gas storage in different cycles.

[0031] As a preferred embodiment, the relational model is represented by the following formula:

[0032] ,

[0033] in, —The liquid discharge volume of the gas reservoir, , —Water intrusion coefficient, —High-pressure cycle pressure coefficient, c d —Low-pressure cycle pressure coefficient.

[0034] As a preferred embodiment, the cumulative water intrusion of the gas storage is obtained according to the following formula:

[0035]

[0036] in, —Cumulative flooding ; —Original gas reserves ; —Cumulative gas production, ; —Cumulative water production, ; —Gas volume coefficient of the original gas reservoir, decimal; —The gas volume factor at time t during gas reservoir development, in decimal form; — Formation water volume factor, decimal.

[0037] As a preferred embodiment, the gas storage water intrusion coefficient is obtained according to the following formula:

[0038]

[0039] in, —Cumulative flooding ; —Water intrusion coefficient, ; —Original formation pressure ; —Formation pressure at time t during gas storage development ; —Gas storage development time, .

[0040] As a preferred embodiment, the high-pressure cycle pressure variation coefficient is obtained using the following formula:

[0041]

[0042] in, —High-pressure cycle pressure coefficient ; —Upper limit pressure for gas storage operation ; —Original formation pressure ; —Number of days the gas storage pressure was higher than the original formation pressure during operation. .

[0043] As a preferred embodiment, the low-pressure cycle pressure change coefficient is obtained using the following formula:

[0044] ,

[0045] Among them, c d —Low-pressure cycle pressure coefficient ; —Lower operating pressure of gas storage ; —Original formation pressure ; —Number of days the gas storage pressure was lower than the original formation pressure during operation. .

[0046] This invention also provides a system for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles, the system comprising:

[0047] The first calculation module is used to obtain the gas storage water intrusion coefficient;

[0048] The second calculation module is used to obtain the pressure change coefficient of the high-pressure cycle and the pressure change coefficient of the low-pressure cycle in the gas storage.

[0049] The data processing module, based on the relational model To obtain the liquid discharge volume of the gas storage in different cycles;

[0050] in, —The liquid discharge volume of the gas reservoir, , —Water intrusion coefficient, —High-pressure cycle pressure coefficient, c d —Low-pressure cycle pressure coefficient.

[0051] As a preferred embodiment, the first calculation module obtains the gas storage water intrusion coefficient according to the following formula:

[0052]

[0053] in, —Cumulative flooding ; —Water intrusion coefficient, ; —Original formation pressure ; —Formation pressure at time t during gas storage development ; —Gas storage development time, .

[0054] As a preferred embodiment, the second calculation module obtains the high-pressure cycle pressure change coefficient according to the following formula:

[0055]

[0056] in, —High-pressure cycle pressure coefficient ; —Upper limit pressure for gas storage operation ; —Original formation pressure ; —Number of days the gas storage pressure was higher than the original formation pressure during operation. .

[0057] As a preferred embodiment, the second calculation module obtains the low-pressure cycle pressure change coefficient according to the following formula:

[0058] ,

[0059] Among them, c d —Low-pressure cycle pressure coefficient ; —Lower operating pressure of gas storage ; —Original formation pressure ; —Number of days the gas storage pressure was lower than the original formation pressure during operation. .

[0060] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0061] Example 1

[0062] like Figure 1 As shown, the method for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles includes the following steps:

[0063] Step 1: Based on the development dynamic analysis data or well test analysis data of the favorable traps of the gas storage facility, obtain the cumulative water intrusion volume of the gas storage facility at a certain moment using the following formula:

[0064] ,

[0065] in, —Cumulative flooding ; —Original gas reserves ; —Cumulative gas production, ; —Cumulative water production, ; —Gas volume coefficient of the original gas reservoir, decimal; —The gas volume factor at time t during gas reservoir development, in decimal form; — Formation water volume factor, decimal.

[0066] Based on dynamic analysis, the original gas reservoir reserves of the favorable trap are estimated to be 1×10⁻⁶. 8 m 3 The original formation pressure was 12 MPa. After 1000 days of development and production, the cumulative gas production was 0.6 × 10⁻⁶. 8m 3 The current formation pressure is 6 MPa, and the original gas reservoir's gas volume factor is 6.6 × 10⁻⁶. -3 The current gas volume factor of the gas reservoir is 4.5 × 10⁻⁶. -3 The formation water volume factor is 1×10 -3 The upper limit pressure of the gas storage facility is 15.5 MPa, and the lower limit pressure is 7 MPa. The gas storage facility operates for 100 days above the original formation pressure (i.e., a 100-day high-pressure operating cycle) and 200 days below the original formation pressure (i.e., a 200-day low-pressure operating cycle). Its injection-production cycle is as follows: Figure 2 As shown.

[0067] Step 2: Calculate the gas storage water intrusion coefficient based on the cumulative water intrusion.

[0068] The formula for calculating the water intrusion coefficient of the gas reservoir is as follows:

[0069] ,

[0070] in, —Cumulative flooding ; —Water intrusion coefficient, ; —Original formation pressure ; —Formation pressure at time t during gas storage development ; —Gas storage development time, .

[0071] Step 3: Calculate the pressure variation coefficients of the high-pressure cycle and low-pressure cycle of the gas storage facility based on the upper and lower limit pressures of the gas storage facility and the original formation pressure of the gas storage facility enclosure.

[0072] The formula for calculating the high-pressure cycle pressure variation coefficient is as follows:

[0073] ,

[0074] in, —High-pressure cycle pressure coefficient ; —Upper limit pressure for gas storage operation ; —Original formation pressure ; —Number of days the gas storage pressure was higher than the original formation pressure during operation. .

[0075] The formula for calculating the low-pressure cycle pressure change coefficient is as follows:

[0076]

[0077] Among them, c d —Low-pressure cycle pressure coefficient ; —Lower operating pressure of gas storage ; —Original formation pressure ; —Number of days the gas storage pressure was lower than the original formation pressure during operation. .

[0078] Step 4: Based on the water intrusion coefficient, the pressure change coefficient of the high-pressure cycle, and the pressure change coefficient of the low-pressure cycle, establish a model for the relationship between the liquid discharge volume of the aquifer-type gas storage facility during different injection and production cycles, and obtain the liquid discharge volume of the gas storage facility in different cycles.

[0079] The model formula is as follows:

[0080] ,

[0081] in, —The liquid discharge volume of the gas reservoir, , —Water intrusion coefficient, —High-pressure cycle pressure coefficient, c d —Low-pressure cycle pressure coefficient.

[0082] The calculated drainage volume for the first injection-production cycle of the gas storage facility is 26,000 m³. 3 .

[0083] Example 2

[0084] like Figure 1 As shown, the method for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles includes the following steps:

[0085] Step 1: Based on the development dynamic analysis data or well test analysis data of the favorable traps of the gas storage facility, obtain the cumulative water intrusion volume of the gas storage facility at a certain moment using the following formula:

[0086] ,

[0087] in, —Cumulative flooding ; —Original gas reserves ; —Cumulative gas production, ; —Cumulative water production, ; —Gas volume coefficient of the original gas reservoir, decimal; —The gas volume factor at time t during gas reservoir development, in decimal form; — Formation water volume factor, decimal.

[0088] Based on dynamic analysis, the original gas reservoir reserves of the favorable trap are estimated to be 2×10⁻⁶. 8 m 3 The original formation pressure was 10 MPa. After 3000 days of development and production, a cumulative gas extraction of 1.0 × 10⁻⁶ MPa was achieved. 8 m 3 A total of 1.0 × 10⁻⁶ water samples were collected. 4 m 3 The current formation pressure is 6 MPa, and the original gas reservoir's gas volume factor is 6.6 × 10⁻⁶. -3 The current gas volume factor of the gas reservoir is 4.5 × 10⁻⁶. -3 The formation water volume factor is 1×10 -3 The upper limit pressure of the gas storage facility is 12 MPa, and the lower limit pressure is 4 MPa. The gas storage facility operates for 150 days above the original formation pressure (i.e., a 150-day high-pressure operating cycle) and 150 days below the original formation pressure (i.e., a 150-day low-pressure operating cycle). Its injection-production cycle is as follows: Figure 3 As shown.

[0089] Step 2: Calculate the gas storage water intrusion coefficient based on the cumulative water intrusion.

[0090] The formula for calculating the water intrusion coefficient of the gas reservoir is as follows:

[0091] ,

[0092] in, —Cumulative flooding ; —Water intrusion coefficient, ; —Original formation pressure ; —Formation pressure at time t during gas storage development ; —Gas storage development time, .

[0093] Step 3: Calculate the pressure variation coefficients of the high-pressure cycle and low-pressure cycle of the gas storage facility based on the upper and lower limit pressures of the gas storage facility and the original formation pressure of the gas storage facility enclosure.

[0094] The formula for calculating the high-pressure cycle pressure variation coefficient is as follows:

[0095] ,

[0096] in, —High-pressure cycle pressure coefficient ; —Upper limit pressure for gas storage operation ; —Original formation pressure ; —Number of days the gas storage pressure was higher than the original formation pressure during operation. .

[0097] The formula for calculating the low-pressure cycle pressure change coefficient is as follows:

[0098] ,

[0099] Among them, c d —Low-pressure cycle pressure coefficient ; —Lower operating pressure of gas storage ; —Original formation pressure ; —Number of days the gas storage pressure was lower than the original formation pressure during operation. .

[0100] Step 4: Based on the water intrusion coefficient, the pressure change coefficient of the high-pressure cycle, and the pressure change coefficient of the low-pressure cycle, establish a model for the relationship between the liquid discharge volume of the aquifer-type gas storage facility during different injection and production cycles, and obtain the liquid discharge volume of the gas storage facility in different cycles.

[0101] The model formula is as follows:

[0102] ,

[0103] in, —The liquid discharge volume of the gas reservoir, , —Water intrusion coefficient, —High-pressure cycle pressure coefficient, c d —Low-pressure cycle pressure coefficient.

[0104] The calculated drainage volume for the first injection-production cycle of the gas storage facility is 22,000 m³. 3 .(like Figure 3 (As shown)

[0105] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles, characterized in that, Includes the following steps: Based on the development dynamic analysis data or well test analysis data of the favorable traps of the gas storage, obtain the cumulative water intrusion of the gas storage at a certain moment; obtain the water intrusion coefficient of the gas storage. Based on the upper and lower limit pressures of the gas storage operation and the original formation pressure of the gas storage enclosure, the pressure change coefficients of the high-pressure cycle and the low-pressure cycle of the gas storage are obtained. Based on the water intrusion coefficient, the pressure change coefficient of the high-pressure cycle and the pressure change coefficient of the low-pressure cycle, a model is established to determine the relationship between the liquid discharge volume of the aquifer gas storage in different injection and production cycles, and the liquid discharge volume of the gas storage in different cycles is obtained. The relational model is represented by the following formula: ， in, —The liquid discharge volume of the gas reservoir, , —Water intrusion coefficient, —High-pressure cycle pressure coefficient, c d —Low-pressure cycle pressure coefficient; The high-pressure cycle pressure variation coefficient is obtained using the following formula: in, —High-pressure cycle pressure coefficient ; —Upper limit pressure for gas storage operation ; —Original formation pressure ; —Number of days the gas storage pressure was higher than the original formation pressure during operation. ; The low-pressure cycle pressure variation coefficient is obtained using the following formula: , Among them, c d —Low-pressure cycle pressure coefficient ; —Lower operating pressure of gas storage ; —Original formation pressure ; —Number of days the gas storage pressure was lower than the original formation pressure during operation. .

2. The method for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles, as described in claim 1, is characterized in that... The cumulative water intrusion volume of the gas storage facility can be obtained using the following formula: in, —Cumulative flooding ; —Original gas reserves ; —Cumulative gas production, ; —Cumulative water production, ; —Gas volume coefficient of the original gas reservoir, decimal; —The gas volume factor at time t during gas reservoir development, in decimal form; — Formation water volume factor, decimal.

3. The method for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles, as described in claim 1, is characterized in that... The gas storage water intrusion coefficient is obtained using the following formula: in, —Cumulative flooding ; —Water intrusion coefficient, ; —Original formation pressure ; —Formation pressure at time t during gas storage development ; —Gas storage development time, .

4. A system for rapidly evaluating the liquid discharge volume of an aquifer-type gas storage facility during different injection and production cycles, characterized in that, The system includes: The first calculation module is used to obtain the gas storage water intrusion coefficient; The second calculation module is used to obtain the pressure change coefficient of the high-pressure cycle and the pressure change coefficient of the low-pressure cycle in the gas storage. The data processing module, based on the relational model To obtain the liquid discharge volume of the gas storage in different cycles; in, —The liquid discharge volume of the gas reservoir, , —Water intrusion coefficient, —High-pressure cycle pressure coefficient, c d —Low-pressure cycle pressure coefficient; The second calculation module obtains the high-pressure cycle pressure change coefficient according to the following formula: in, —High-pressure cycle pressure coefficient ; —Upper limit pressure for gas storage operation ; —Original formation pressure ; —Number of days the gas storage pressure was higher than the original formation pressure during operation. ; The second calculation module obtains the low-pressure cycle pressure change coefficient according to the following formula: , Among them, c d —Low-pressure cycle pressure coefficient ; —Lower operating pressure of gas storage ; —Original formation pressure ; —Number of days the gas storage pressure was lower than the original formation pressure during operation. .

5. The system according to claim 4, characterized in that, The first calculation module obtains the gas storage water intrusion coefficient according to the following formula: in, —Cumulative flooding ; —Water intrusion coefficient, ; —Original formation pressure ; —Formation pressure at time t during gas storage development ; —Gas storage development time, .

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