Method, system, equipment and medium for identifying water invasion quantity in production process of water and gas reservoir well

Abstract

The invention provides a water invasion amount identification method, system and device in a water and gas reservoir well production process, and a medium. The method comprises the following steps: establishing a corresponding equivalent water invasion model based on a relative position relation of a water area and a gas area of a reservoir well; establishing a water invasion substance balance model according to the equivalent water invasion model and the pressure measurement time point division stages over the years; iterating the water invasion material balance model based on the principle that the stage water area pressure is linearly decreased according to the stage water invasion amount; on the basis of the iterated water invasion substance balance model, evaluating water body ranking and guiding water drainage and gas production of well accumulation; according to the method, the equivalent water invasion models corresponding to different well mining geologic models are selected, the iterative algorithm meeting the gas-water flowing material balance equation is established, the well historical pressure parameters and the reservoir parameters are obtained, the current water invasion amount is obtained through calculation, and then the current water invasion amount is used for evaluating the water body and guiding water drainage and gas production of the gas field well. The conditions that a crack water invasion model cannot accurately describe and multi-parameter representation is difficult in the prior art are avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas field development, and in particular relates to a method, system, equipment and medium for identifying water intrusion in a water gas reservoir well production process. Background Art

[0002] During the development of water-containing gas reservoirs, water invasion causes water to come out of the production wells, affecting the well production and gas reservoir recovery rate. It is necessary to evaluate the water body to guide the drainage and gas production of the gas field, and the key technology is the calculation of the water invasion amount.

[0003] In the existing technology, the calculation method of water invasion volume for gas reservoirs with relatively average physical properties such as sandstone is relatively mature, the water invasion model can be directly established using the geological model, and the direction of water invasion is relatively definite.

[0004] However, for fractured gas reservoirs such as carbonate rocks, water invasion is greatly affected by fracture pipe flow, and it is impossible to establish a water invasion model based on the direct use of geological models. The water invasion process is usually also an unstable process. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a method, system, equipment and medium for identifying water intrusion in the production process of water gas reservoir wells, which can avoid the inability to accurately characterize the fracture water intrusion model and the difficulty of multi-parameter characterization in the prior art.

[0006] The present invention is achieved through the following technical solutions:

[0007] A method for identifying water intrusion during the production process of a water gas reservoir well comprises the following steps:

[0008] Based on the relative position relationship between the water zone and the gas zone of the reservoir well, a corresponding equivalent water invasion model is established;

[0009] The water intrusion material balance model is established according to the equivalent water intrusion model and the pressure measurement time points in previous years.

[0010] The water intrusion material balance model is iterated based on the principle that the stage water zone pressure decreases linearly according to the stage water intrusion amount;

[0011] The iterative water intrusion material balance model is used to evaluate the drainability of water bodies and guide the drainage and gas production of reservoir wells.

[0012] Furthermore, the establishment of a corresponding equivalent water invasion model based on the relative position relationship between the water zone and the gas zone of the reservoir well includes:

[0013] Type I model, the type I model is a 1 / 4 sphere, the water zone and the gas zone are nested in the sphere in sequence, the well is located at the center of the sphere and connected to the gas zone;

[0014] Type II model: Type II model is a 1 / 2 sphere, with the water zone and gas zone nested in the sphere in sequence, and the well is located in the center of the sphere and connected to the gas zone

[0015] Type III model: The type III model is a sphere, in which the water zone and the gas zone are nested in sequence, and the well is located at the center of the sphere and connected to the gas zone.

[0016] Furthermore, the water intrusion material balance model is:

[0017] The water intrusion is the sum of the water intrusion in each stage, the integral of the water intrusion velocity in each stage and the stage time.

[0018] Furthermore, the water invasion speed is: the water production index multiplied by the pressure difference between the water zone and the gas zone, and the relationship is Ve=J×(Pw-Pr);

[0019] Among them, the water production index is: J = [0.5428·K·h·f] / [u·(lnr-0.75)], K is the permeability of the gas reservoir, h is the effective thickness of the gas reservoir, which is obtained through the logging interpretation or well test interpretation data of the well, r is the converted radius of the gas-bearing area of ​​the gas reservoir, which is obtained by converting the evaluated reserves of the gas zone into the radius of the corresponding equivalent water invasion model; the parameter Pr is the current formation pore pressure of the gas reservoir, which is obtained through the pressure test of the wells in previous years.

[0020] Furthermore, the process of iterative water intrusion material balance model is:

[0021] The pressure value of the gas zone pressure Pr in the stage is equal to the average of the pressure values ​​measured in the previous stage and the current stage, then the pressure of the gas zone in the nth stage (Pr)n=[(Pr)n+(Pr)n-1] / 2;

[0022] The stage water zone pressure decreases linearly according to the stage water intrusion, so the water zone pressure in the n-1 stage is (Pw)n-1=(Pr)1[1–(We)n-1 / (We)max].

[0023] Furthermore, during the iterative water intrusion material balance model:

[0024] The iteration of type I model is: type I equivalent water intrusion model (We)max = 0.25·Ct·Wi·P1;

[0025] The iteration of type II model is: type II equivalent water intrusion model (We)max = 0.5·Ct·Wi·P1;

[0026] The iteration of type III model is: type III equivalent water intrusion model (We)max = Ct·Wi·P1;

[0027] Wherein, Wi is the movable water body, which is obtained by calculating the product of the water body size and the movable coefficient through the geological model. The water body size is obtained through the geological model using methods including structural extrapolation and / or geological modeling. The movable coefficient is obtained through lithological experiments, including the water inflow and water withdrawal weighing method, the water inflow and water withdrawal nuclear magnetic resonance method and / or the capillary pressure curve method. The elastic compression coefficient of the reservoir space Ct is obtained through lithological mechanics experiments or the empirical formula method of porosity and pressure.

[0028] Furthermore, the process of evaluating the drainability of water bodies and guiding the drainage and gas production of reservoir wells based on the iterative water invasion material balance model is as follows:

[0029] Through the obtained water influx parameters, multiple auxiliary parameters can be calculated to evaluate water bodies and their drainability, such as water influx velocity, water drive index and water influx replacement coefficient.

[0030] A water intrusion identification system in the production process of a water gas reservoir well, comprising:

[0031] The equivalent water invasion model module is used to establish the corresponding equivalent water invasion model based on the relative position relationship between the water zone and the gas zone of the reservoir well;

[0032] The water intrusion material balance model module is used to establish a water intrusion material balance model according to the equivalent water intrusion model and the pressure measurement time points in previous years;

[0033] Iteration module, used to iterate the water intrusion material balance model based on the principle that the stage water zone pressure decreases linearly according to the stage water intrusion amount;

[0034] The application module is used to evaluate the drainability of water bodies and guide the drainage and gas production of reservoir wells based on the iterative water invasion material balance model.

[0035] A computer device comprises a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, steps of a method for identifying water intrusion in a water gas reservoir well production process are implemented.

[0036] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of a method for identifying water intrusion during the production process of a water gas reservoir well.

[0037] Compared with the prior art, the present invention has the following beneficial technical effects:

[0038] The present invention provides a method, system, equipment and medium for identifying water intrusion during the production process of a water gas reservoir well, including the following steps: establishing a corresponding equivalent water intrusion model based on the relative position relationship between the water zone and the gas zone of the reservoir well; establishing a water intrusion material balance model according to the equivalent water intrusion model and the time points of pressure measurement in previous years; iterating the water intrusion material balance model based on the principle that the stage water zone pressure decreases linearly according to the stage water intrusion; evaluating the water body dischargeability and guiding the drainage and gas production of the reservoir well based on the iterated water intrusion material balance model; the present application selects the equivalent water intrusion model corresponding to the geological model of different well production, establishes an iterative algorithm that satisfies the gas-water flow material balance equation, obtains the historical pressure parameters and reservoir parameters of the well, calculates the current water intrusion, and then uses it to evaluate the water body and guide the drainage and gas production of the gas field well. Since the above method adopts the equivalent water intrusion model, the parameters can be simplified, especially for fractured water gas reservoirs, avoiding the situation in which the fracture water intrusion model in the prior art cannot be accurately characterized and the difficulty of multi-parameter characterization. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a flow chart of a method for identifying water intrusion during the production process of a water gas reservoir well according to the present invention;

[0040] Figure 2 It is a diagram of equivalent water invasion model for different gas reservoirs of the present invention;

[0041] Figure 3 It is a schematic diagram of the relationship between the well and the gas-water interface in the equivalent water invasion model diagram of the present invention;

[0042] Figure 4 This is a schematic diagram of the type II equivalent water intrusion model of the present invention;

[0043] Figure 5 This is a schematic diagram of the type III equivalent water intrusion model of the present invention;

[0044] Figure 6 This is a schematic diagram of the type I equivalent water intrusion model of the present invention;

[0045] Figure 7 A display curve graph of the calculation results in the example. DETAILED DESCRIPTION

[0046] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0047] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 creative work should fall within the scope of protection of the present invention.

[0048] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0049] During the development of gas reservoirs with water, water may invade the gas-water zone during the well production process. The amount of intrusion needs to be calculated to evaluate the water body and guide the drainage and gas production of gas field wells.

[0050] In the existing technology, the calculation method of water invasion volume for gas reservoirs with relatively average physical properties such as sandstone is relatively mature, the water invasion model can be directly established using the geological model, and the direction of water invasion is relatively definite.

[0051] However, for fractured gas reservoirs such as carbonate rocks, water invasion is greatly affected by fracture pipe flow, and it is impossible to directly use the geological model to establish a water invasion model. The water invasion process is usually an unstable process. Therefore, based on the actual common geological model of water-bearing gas reservoirs, an equivalent water invasion model chart is established, and an iterative algorithm that satisfies the material balance equation of gas-water flow is used to calculate the water invasion amount.

[0052] The present invention provides a method for identifying water intrusion during the production process of a water gas reservoir well. Figure 1 As shown, the following steps are included:

[0053] Based on the relative position relationship between the water zone and the gas zone of the reservoir well, a corresponding equivalent water invasion model is established;

[0054] The water intrusion material balance model is established according to the equivalent water intrusion model and the pressure measurement time points in previous years.

[0055] The water intrusion material balance model is iterated based on the principle that the stage water zone pressure decreases linearly according to the stage water intrusion amount;

[0056] The iterative water intrusion material balance model is used to evaluate the drainability of water bodies and guide the drainage and gas production of reservoir wells.

[0057] Preferably, the establishing of a corresponding equivalent water invasion model based on the relative position relationship between the water zone and the gas zone of the reservoir well comprises:

[0058] Type I model, such as Figure 6 As shown, the type I model is a 1 / 4 sphere, the water zone and the gas zone are nested in the sphere in sequence, the well is located at the center of the sphere and connected to the gas zone. Specifically, Figure 2 and Figure 3 As shown, the water-driven gas reservoirs in the type I model can be divided into two categories, edge water gas reservoirs and bottom water gas reservoirs, from the perspective of water body production. Among them, the edge water is only partially in contact with the gas reservoir, and mostly exists in layered gas reservoirs. The bottom water gas reservoir is the main form of massive gas reservoirs, and the ground water gas reservoir includes two situations, namely, H1 is less than H2 and H1 is greater than H2, wherein H1 is the opening thickness of the well, and H2 is the distance from the bottom of the opening thickness to the gas-water interface.

[0059] Type II models, such as Figure 4 As shown, the type II model is a 1 / 2 sphere, with the water zone and gas zone nested in the sphere in sequence, and the well is located at the center of the sphere and connected to the gas zone.

[0060] Type III model, such as Figure 5 As shown, the type III model is a sphere, the water zone and the gas zone are nested in the sphere in sequence, and the well is located in the center of the sphere and connected to the gas zone.

[0061] It should be noted that, in the initial state, there is an equivalent gas-water interface between the gas zone and the water zone, and the pressure of the gas zone is equal to the pressure of the water zone at the gas-water interface, and there is no flow. After the well is produced, the pressure of the gas zone begins to drop, the pressure of the water zone is greater than the pressure of the gas zone, and the water zone flows to the gas zone, that is, water invasion occurs, and the size of the invasion amount is the water invasion amount. After the well continues to produce, the pressure of the gas zone continues to drop, and the pressure of the water zone drops due to water invasion, but the pressure of the water zone is still greater than the pressure of the gas zone, and the water zone flows to the gas zone, that is, water invasion continues to occur. After the water invasion amount increases to a certain extent, the fluid produced by the well is gas and water.

[0062] Preferably, the water intrusion material balance model is:

[0063] The water intrusion is the sum of the water intrusion in each stage, the integral of the water intrusion velocity in each stage and the stage time.

[0064] Furthermore, the water invasion speed is: the water production index multiplied by the pressure difference between the water zone and the gas zone, and the relationship is Ve=J×(Pw-Pr);

[0065] The water production index is: J = [0.5428·K·h·f] / [u·(lnr-0.75)], where K is the permeability of the gas reservoir, h is the effective thickness of the gas reservoir, f is the model coefficient, and the I, II, and III models are 0.25, 0.5, and 1, respectively, which is obtained through the logging interpretation or well test interpretation data of the well. r is the converted radius of the gas-bearing area of ​​the gas reservoir, which is obtained by converting the evaluated reserves of the gas zone into the radius of the corresponding equivalent water invasion model; the parameter Pr is the current formation pore pressure of the gas reservoir, which is obtained through the pressure test of the wells in previous years.

[0066] Furthermore, the process of iterative water intrusion material balance model is:

[0067] The pressure value of the gas zone pressure Pr in the stage is equal to the average of the pressure values ​​measured in the previous stage and the current stage, then the pressure of the gas zone in the nth stage (Pr)n=[(Pr)n+(Pr)n-1] / 2;

[0068] The stage water zone pressure decreases linearly according to the stage water intrusion, so the water zone pressure in the n-1 stage is (Pw)n-1=(Pr)1[1–(We)n-1 / (We)max].

[0069] Furthermore, during the iterative water intrusion material balance model:

[0070] The iteration of type I model is: type I equivalent water intrusion model (We)max = 0.25·Ct·Wi·P1;

[0071] The iteration of type II model is: type II equivalent water intrusion model (We)max = 0.5·Ct·Wi·P1;

[0072] The iteration of type III model is: type III equivalent water intrusion model (We)max = Ct·Wi·P1.

[0073] Wherein, Wi is the movable water body, which is obtained by calculating the product of the water body size and the movable coefficient through the geological model. The water body size is obtained through the geological model using methods including structural extrapolation and / or geological modeling. The movable coefficient is obtained through lithological experiments, including the water inflow and water withdrawal weighing method, the water inflow and water withdrawal nuclear magnetic resonance method and / or the capillary pressure curve method. The elastic compression coefficient of the reservoir space Ct is obtained through lithological mechanics experiments or the empirical formula method of porosity and pressure.

[0074] Preferably, the process of evaluating the drainability of water bodies and guiding the drainage and gas production of reservoir wells based on the iterative water invasion material balance model is as follows:

[0075] By obtaining the water invasion parameters, multiple auxiliary parameters can be calculated to evaluate water bodies and their drainability, such as water invasion velocity, that is, the change in water invasion per unit time period, water drive index, that is, the ratio of groundwater invasion to the volume of produced fluid, and water invasion replacement coefficient, that is, the ratio of the volume of net underground water invasion to the volume of gas reserves.

[0076] Embodiment 1:

[0077] The first step is to select equivalent water intrusion, such as Figure 2 As shown, the embodiment illustrated in this embodiment is Model II;

[0078] The second step is to establish the water intrusion material balance equation, type II equivalent water intrusion model (We)max = 0.5·Ct·Wi·P1;

[0079] The third step is to collect and organize parameters and calculate the water production index, as shown in Table 1. The calculation parameters are Ct, Wi, and Pr (where P1 is the initial formation pressure, corresponding to the test pressure in 2014);

[0080] Table 1.

[0081]

[0082] The water production index is calculated by the formula J = [0.5428·K·h·0.5] / [u·(lnr-0.75)].

[0083] The fourth step is to iteratively calculate the water invasion. Pr corresponds to the formation pressure of each test, (Pr)n is [(Pr)n+(Pr)n-1] / 2, (Pw)n-1 is P1×(1-stage cumulative water invasion / (We)max), (We)max) is calculated to be 42662880 square meters. n represents the stage, and the values ​​1, 2, 3, etc. correspond to 2014, 2015, 2016, etc. according to the test time, as shown in Table 2.

[0084] Table 2.

[0085]

[0086] The fifth step is to evaluate the drainability of the water body and guide drainage and gas production. Combined with the gas production, calculate the water drive index (its value is ≤0.1 for weak water drive, 0.1-0.3 for medium water drive, and >0.3 for strong water drive) and the water invasion replacement coefficient (its value is ≤0.15 for inactive, 0.15-0.4 for sub-active, and >0.4 for active). Under normal circumstances, under the conditions of medium water drive and sub-active water invasion, drainage feasibility is strong, drainage difficulty is small, and there are many drainage process options. Figure 7As shown, the cumulative water invasion volume in 2021 was calculated to be 158,288 cubic meters, the water drive index was calculated to be 0.22, and the water invasion replacement coefficient was 0.21, which is characterized by moderate water drive and secondary active water invasion. The conditions for drainage are met, and the next step is to implement drainage gas production development to improve the gas reservoir recovery rate.

[0087] The present invention provides a water intrusion identification system in the production process of a water gas reservoir well, comprising:

[0088] The equivalent water invasion model module is used to establish the corresponding equivalent water invasion model based on the relative position relationship between the water zone and the gas zone of the reservoir well;

[0089] The water intrusion material balance model module is used to establish a water intrusion material balance model according to the equivalent water intrusion model and the pressure measurement time points in previous years;

[0090] Iteration module, used to iterate the water intrusion material balance model based on the principle that the stage water zone pressure decreases linearly according to the stage water intrusion amount;

[0091] The application module is used to evaluate the drainability of water bodies and guide the drainage and gas production of reservoir wells based on the iterative water invasion material balance model.

[0092] In another embodiment of the present invention, a computer device is provided, the computer device comprising a processor and a memory, the memory being used to store a computer program, the computer program comprising program instructions, and the processor being used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, and is specifically suitable for loading and executing one or more instructions in a computer storage medium to implement a corresponding method flow or corresponding function; the processor described in the embodiment of the present invention can be used for the operation of a method for identifying water intrusion in a water gas reservoir well production process.

[0093] In another embodiment of the present invention, the present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device for storing programs and data. It is understandable that the computer-readable storage medium here can include both built-in storage media in the computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the method for identifying water intrusion in the production process of a water gas reservoir well in the above embodiment.

[0094] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0095] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0096] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0097] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for identifying water intrusion during the production process of a water gas reservoir well, characterized in that: The following steps are involved: Based on the relative position relationship between the water zone and the gas zone of the reservoir well, a corresponding equivalent water invasion model is established; The water intrusion material balance model is established according to the equivalent water intrusion model and the pressure measurement time points in previous years. The water intrusion material balance model is iterated based on the principle that the stage water zone pressure decreases linearly according to the stage water intrusion amount; The iterative water intrusion material balance model is used to evaluate the drainability of water bodies and guide the drainage and gas production of reservoir wells.

2. According to claim 1, a method for identifying water intrusion during the production process of a water gas reservoir well, characterized in that: The corresponding equivalent water invasion model established based on the relative position relationship between the water zone and the gas zone of the reservoir well includes: Type I model, the type I model is a 1 / 4 sphere, the water zone and the gas zone are nested in the sphere in sequence, the well is located at the center of the sphere and connected to the gas zone; Type II model: Type II model is a 1 / 2 sphere, with the water zone and gas zone nested in the sphere in sequence, and the well is located in the center of the sphere and connected to the gas zone Type III model: The type III model is a sphere, in which the water zone and the gas zone are nested in sequence, and the well is located at the center of the sphere and connected to the gas zone.

3. The method for identifying water intrusion during the production process of a water gas reservoir well according to claim 2, characterized in that: The material balance model of water intrusion is: The water intrusion is the sum of the water intrusion in each stage, the integral of the water intrusion velocity in each stage and the stage time.

4. The method for identifying water intrusion during the production process of a water gas reservoir well according to claim 3, characterized in that: The water invasion speed is: the water production index multiplied by the pressure difference between the water zone and the gas zone, and the relationship is Ve=J×(Pw-Pr); Among them, the water production index is: J = [0.5428·K·h·f] / [u·(lnr-0.75)], K is the permeability of the gas reservoir, h is the effective thickness of the gas reservoir, which is obtained through the logging interpretation or well test interpretation data of the well, r is the converted radius of the gas-bearing area of ​​the gas reservoir, which is obtained by converting the evaluated reserves of the gas zone into the radius of the corresponding equivalent water invasion model; the parameter Pr is the current formation pore pressure of the gas reservoir, which is obtained through the pressure test of the wells in previous years.

5. A method for identifying water intrusion during the production process of a water gas reservoir well according to claim 4, characterized in that: The process of iterative water intrusion material balance model is: The pressure value of the gas zone pressure Pr in the stage is equal to the average of the pressure values ​​measured in the previous stage and the current stage, then the pressure of the gas zone in the nth stage (Pr)n=[(Pr)n+(Pr)n-1] / 2; The stage water zone pressure decreases linearly according to the stage water intrusion, so the water zone pressure in the n-1 stage is (Pw)n-1=(Pr)1[1–(We)n-1 / (We)max].

6. A method for identifying water intrusion during the production process of a water gas reservoir well according to claim 5, characterized in that: During the iterative water intrusion material balance model: The iteration of type I model is: type I equivalent water intrusion model (We)max = 0.25·Ct·Wi·P1; The iteration of type II model is: type II equivalent water intrusion model (We)max = 0.5·Ct·Wi·P1; The iteration of type III model is: type III equivalent water intrusion model (We)max = Ct·Wi·P1; Wherein, Wi is the movable water body, which is obtained by calculating the product of the water body size and the movable coefficient through the geological model. The water body size is obtained through the geological model using methods including structural extrapolation and / or geological modeling. The movable coefficient is obtained through lithological experiments, including the water inflow and water withdrawal weighing method, the water inflow and water withdrawal nuclear magnetic resonance method and / or the capillary pressure curve method. The elastic compression coefficient of the reservoir space Ct is obtained through lithological mechanics experiments or the empirical formula method of porosity and pressure.

7. The method for identifying water intrusion during the production process of a water gas reservoir well according to claim 1, characterized in that: The process of evaluating the drainability of water bodies and guiding the drainage and gas production of reservoir wells based on the iterative water invasion material balance model is as follows: Through the obtained water influx parameters, multiple auxiliary parameters can be calculated to evaluate water bodies and their drainability, such as water influx velocity, water drive index and water influx replacement coefficient.

8. A water intrusion identification system during the production process of a water gas reservoir well, characterized in that: A method for identifying water intrusion during the production process of a water gas reservoir well according to any one of claims 1 to 7, comprising: The equivalent water invasion model module is used to establish the corresponding equivalent water invasion model based on the relative position relationship between the water zone and the gas zone of the reservoir well; The water intrusion material balance model module is used to establish a water intrusion material balance model according to the equivalent water intrusion model and the pressure measurement time points in previous years; Iteration module, used to iterate the water intrusion material balance model based on the principle that the stage water zone pressure decreases linearly according to the stage water intrusion amount; The application module is used to evaluate the drainability of water bodies and guide the drainage and gas production of reservoir wells based on the iterative water invasion material balance model.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method for identifying water intrusion in the production process of a water gas reservoir well as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of a method for identifying water intrusion in a water gas reservoir well production process as described in any one of claims 1 to 7 are implemented.

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