Fractured water sandstone gas reservoir development production allocation method and system

Abstract

The invention relates to a fractured water sandstone gas reservoir development production allocation method and system, and belongs to the field of oil and gas field dynamic analysis and research. The method comprises the steps that an optimized production allocation well is determined based on the production well testing comprehensive permeability, the storage capacity ratio and the breaking joint directional strength coefficient; establishing a matrix-fracture gas supply coupling chart for the determined optimized production allocation well; on the basis of the matrix-fracture gas supply coupling chart and the critical water invasion pressure difference, energy loss constraints are reduced, and the production allocation area with the optimized production allocation ratio of the production allocation well is obtained through diagrams. The water breakthrough gas well production allocation method is achieved through a critical water invasion pressure difference, gas well pressure drop rate and gas production index linkage dynamic constraint diagram method, the problems that reasonable productivity calibration and scientific and reasonable production allocation are difficult after gas well water breakthrough in a gas field are solved, the scientific production system of the water breakthrough gas well is effectively formulated, and the production efficiency of the gas well is improved. And a foundation is laid for reasonable and efficient development of gas wells and gas fields.

Description

Technical Field

[0001] The invention belongs to the field of oil and gas field dynamic analysis research, and particularly relates to a production allocation method and system for developing fractured water-bearing sandstone gas reservoirs. Background Art

[0002] During the development of fractured, water-bearing sandstone gas reservoirs, water intrusion can cause water production in gas wells, increasing the difficulty of reservoir development and production. It can also lead to gas well productivity loss, reduced gas recovery, and negatively impact the efficiency of gas reservoir development. Therefore, rationally allocating production to gas wells, arranging production capacity, and controlling heterogeneous water intrusion in fractures are crucial for extending the water-free gas production period, reducing water-locked gas in fractures, and improving recovery. Currently, research on production allocation methods after water intrusion in gas reservoirs is still immature, primarily based on methods such as the critical production pressure differential between edge and bottom water and the anisotropic critical water cone yield method. These studies are mostly based on homogeneous gas reservoir conditions and are not applicable to fractured, heterogeneous gas reservoirs. Summary of the Invention

[0003] In response to the above problems, the present invention provides a method and system for development and production allocation of fractured water-bearing sandstone gas reservoirs, which is suitable for gas well production capacity calibration and scientific production allocation after water appears in fractured heterogeneous gas reservoirs, and provides a new method applicable to production allocation of water-invaded gas wells. It helps to formulate scientific production allocation plans for each water-invaded gas well and arrange scientific production. It can control the non-uniform water invasion of fractured water-bearing gas reservoirs to a certain extent, slow down the water invasion speed of the dominant channel of the fracture, avoid the formation of large-scale fracture water-sealed gas, extend the water-free production time of gas wells in fractured water-bearing gas reservoirs, and thus improve the ultimate recovery rate of the gas reservoir.

[0004] A first object of the present invention is to provide a method for developing and allocating production of fractured water-bearing sandstone gas reservoirs, the method comprising:

[0005] Determine the optimal production well allocation based on the comprehensive permeability, storage volume ratio and fracture pointing strength coefficient of the production well test;

[0006] For the optimized production wells, a matrix-fracture gas supply coupling chart is established;

[0007] Based on the matrix-fracture gas supply coupling diagram, as well as the critical water invasion pressure difference and energy loss reduction constraints, the production allocation area with optimized production ratio of the allocated production wells was graphically determined.

[0008] In a specific embodiment of the present invention, the comprehensive permeability and storage-volume ratio are obtained from production well test data.

[0009] In a specific embodiment of the present invention, obtaining the fracture pointing intensity coefficient includes:

[0010] Based on the discrete fractures, the fracture permeability is coarsened into the grid using the Oda Block algorithm;

[0011] According to the roughened curve, the fracture pointing intensity coefficient is obtained.

[0012] In a specific embodiment of the present invention, determining the optimized production well allocation based on the comprehensive permeability, storage-volume ratio and fracture pointing strength coefficient of the production well test includes:

[0013] A correlation scatter plot is established with the logarithm of the comprehensive permeability as the ordinate and the storage capacity ratio as the abscissa;

[0014] According to the linear law of the correlation scatter plot, the flow category of the single well is divided;

[0015] The optimized production wells are determined based on the flow category of the single well and the fault pointing strength coefficient.

[0016] In a specific embodiment of the present invention, the flow categories of the single well include homogeneous fracture network production wells and fracture-dominated production wells.

[0017] In a specific embodiment of the present invention, the production allocation area for optimizing the production ratio of the allocated production wells is illustrated based on the matrix-fracture gas supply coupling diagram, the critical water invasion pressure difference, and the energy loss reduction constraint, including:

[0018] Determine the critical invasion pressure difference of edge and bottom water based on the changes in gas-liquid ratio, chloride radical and production pressure difference of production wells;

[0019] Determine the energy loss reduction constraint based on the relationship between the production well gas production index and the pressure drop rate;

[0020] Taking the critical water invasion pressure difference and the reduction of capacity loss as the limiting conditions, a limiting line is drawn on the single-well matrix-fracture gas supply coupling chart to obtain the production allocation area with the optimized production ratio of the allocated production wells.

[0021] A second object of the present invention is to provide a production allocation system for the development of fractured water-bearing sandstone gas reservoirs, the system comprising:

[0022] The determination module is used to determine the optimized production wells based on the comprehensive permeability, storage volume ratio and fracture pointing strength coefficient of the production well test;

[0023] Establish a chart module to establish a matrix-fracture gas supply coupling chart for the determined optimized production wells;

[0024] The graphical module is used to illustrate the production allocation area based on the matrix-fracture gas supply coupling diagram, critical water invasion pressure difference, and energy loss reduction constraints to optimize the production ratio of the allocated production wells.

[0025] In a specific embodiment of the present invention, obtaining the fracture pointing intensity coefficient includes:

[0026] Based on the discrete fractures, the fracture permeability is coarsened into the grid using the Oda Block algorithm;

[0027] According to the roughened curve, the fracture pointing intensity coefficient is obtained.

[0028] In a specific embodiment of the present invention, the determination module includes a first submodule, a second submodule and a third submodule;

[0029] The first submodule is used to establish a correlation scatter plot with the logarithm of the comprehensive permeability as the vertical coordinate and the storage capacity ratio as the horizontal coordinate;

[0030] The second submodule is used to classify the flow categories of individual wells based on the linear law of the correlation scatter plot;

[0031] The third submodule is used to determine the optimized production wells based on the flow category and fracture pointing intensity coefficient of the single well.

[0032] In a specific embodiment of the present invention, the diagram module includes a fourth submodule, a fifth submodule, and a sixth submodule;

[0033] The fourth submodule is used to determine the critical invasion pressure difference of edge and bottom water based on the changes in the gas-liquid ratio, chloride radical and production pressure difference of the production well;

[0034] The fifth submodule is used to determine the energy loss reduction constraint based on the relationship between the production well gas production index and the pressure drop rate;

[0035] The sixth submodule is used to use the critical water invasion pressure difference and the reduction of capacity loss as constraint conditions, draw constraint lines on the single-well matrix-fracture gas supply coupling map, and obtain the production allocation area with the optimized production ratio of the allocated production wells.

[0036] Beneficial effects of the present invention:

[0037] The present invention provides a method and system for production allocation for the development of fractured water-bearing sandstone gas reservoirs. By adopting a "dynamic constraint graphical method for the linkage of critical water invasion pressure difference, gas well pressure drop rate and gas production index", a method for production allocation for water-bearing gas wells is realized. This solves the problems of reasonable production capacity calibration and scientific and reasonable production allocation difficulties after water is seen in gas wells in gas fields, effectively solves the problem of formulating a scientific production system for water-bearing gas wells, and lays the foundation for the rational and efficient development of gas wells and gas fields.

[0038] The following specific effects were found through the implementation of the gas reservoir production well in Example D of the present invention:

[0039] Improved gas well production stability. Under high-pressure differential production conditions, the pressure drop rate for a well with low fracture development in western China was 1.55 MPa / mon, reducing gas well production from 1.5 million cubic meters per day to 1.2 million cubic meters per day. Through optimized production allocation, the pressure drop rate is now 0.31 MPa / mon, and the open flow rate has been restored to 1.5 million cubic meters per day, significantly improving the stable production of individual wells.

[0040] Water control in gas wells has been significantly effective. Through production control in three abnormally wells, the water-gas ratio has been reduced in a stepwise manner, and the open-flow rate has increased slightly. This has mitigated the influx of edge water, allowing gas to flow primarily as a continuous phase within the channel, reducing energy losses associated with two-phase flow and mitigating the risk of water lock in fractured reservoirs. The water-free gas production period is expected to be extended by 150 to 200 days, resulting in cumulative gas production of 145 million cubic meters and oil production of 12,700 tons.

[0041] The method and system provided by this invention effectively calibrates gas well production capacity and rationally allocates production after water intrusion in fractured, water-bearing sandstone gas reservoirs, helping to delay water intrusion and improve recovery. It can also provide reference and guidance for research on scientific and rational production allocation of gas wells in the mid-to-late development phase of other fractured, water-bearing sandstone gas fields.

[0042] 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, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0044] Figure 1 A flow chart of a production allocation method for developing a fractured water-bearing sandstone gas reservoir according to an embodiment of the present invention is shown;

[0045] Figure 2 shows a crack pointing intensity pointing morphology diagram according to an embodiment of the present invention;

[0046] Figure 3 A scatter plot showing correlations between different flow channel storage capacity ratios and formation coefficients according to an embodiment of the present invention is shown;

[0047] Figure 4 A result diagram showing determination of a production well of a D gas reservoir according to an embodiment of the present invention based on a correlation scatter diagram is shown;

[0048] Figure 5 shows a graph of the productivity and production change of the D5 well before optimization according to an embodiment of the present invention;

[0049] Figure 6 A diagram showing the matrix-fracture gas supply coupling of the eastern production well of the D gas reservoir according to an embodiment of the present invention is shown;

[0050] Figure 7 A diagram showing the matrix-fracture gas supply coupling of a production well in the western part of the D gas reservoir according to an embodiment of the present invention is shown;

[0051] Figure 8 The relationship between the gas production index and the pressure drop rate of the D5 production well according to an embodiment of the present invention is shown;

[0052] Figure 9 The diagram shows the results of the matrix-fracture gas supply coupling diagram of the D5 production well according to an embodiment of the present invention;

[0053] Figure 10 The production curve of D5 well after optimized production allocation according to an embodiment of the present invention is shown;

[0054] Figure 11 A framework diagram of a production allocation system for developing fractured water-bearing sandstone gas reservoirs according to an embodiment of the present invention is shown;

[0055] In the figure: determination module 1; plate creation module 2; diagram module 3. DETAILED DESCRIPTION

[0056] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying 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 making creative efforts shall fall within the scope of protection of the present invention.

[0057] like Figure 1 As shown, a production allocation method for developing a fractured water-bearing sandstone gas reservoir according to an embodiment of the present invention includes:

[0058] Step S1: Determine the optimized production wells based on the comprehensive permeability, storage volume ratio and fracture pointing strength coefficient of the production well test;

[0059] Step S2: establishing a matrix-fracture gas supply coupling chart for the determined optimized production well;

[0060] Step S3: Based on the matrix-fracture gas supply coupling diagram, the critical water invasion pressure difference, and the energy loss reduction constraint, a production allocation area is graphically obtained to optimize the production ratio of the allocated production wells.

[0061] In step S1, the comprehensive permeability and storage-volume ratio are obtained from production well test data.

[0062] In step S1, obtaining the fracture pointing intensity coefficient includes:

[0063] Based on the discrete fractures, the fracture permeability is coarsened into the grid using the Oda Block algorithm (the "Oda Block" algorithm is a parallel calculation method for large-scale data sets. The algorithm divides the data set into multiple small blocks and processes these small blocks in parallel on multiple processors to speed up data processing).

[0064] According to the roughened curve, the fracture pointing intensity coefficient is obtained.

[0065] In steps A1-A2, the fracture permeability is coarsened into the grid using the Oda Block algorithm, and the resulting curve is the relationship between the mesh attribute fracture permeability X and the fracture permeability Y, as shown in FIG. Figure 2 As shown in Figure 2, the relationship between the grid attribute fracture permeability X and fracture permeability Y can express the fracture plane conductivity condition;

[0066] In actual operation, the relationship between the grid attributes crack permeability X and crack permeability Y is Figure 1 Generally divided into two types (weak pointing form and strong pointing form), weak pointing form such as Figure 2 As shown in ab, the strong pointing shape is as follows Figure 2 Shown in cd;

[0067] from Figure 2 Zhongb and Figure 2 From d, we can see that in the weak directional form, if the fault has three or more directions, the intensity coefficient k = (kx1 + kx2 + kx3 + ...kyn) / (ky1 + ky2 + ky3 + ...kyn); in the strong directional form, if the fault has only one direction, the intensity coefficient k = kx1 / ky1. Among them, kx1, kx2, kx3, ..., etc. are the grid attribute fracture permeability X, ky1, ky2, ky3, ...kyn, etc. are the grid attribute fracture permeability Y.

[0068] The larger the fault pointing intensity coefficient, the more it indicates that the single-direction fracture is dominant and the fracture system pressure drop is fast. The closer the fault pointing intensity coefficient is to 1, the more it indicates that the matrix-fracture pressure drop is high due to the homogeneity and fracture network control.

[0069] The above steps are used to characterize the strength of the flow channel. The larger the value, the stronger the directivity, and the closer the value is to 1, the weaker the directivity. Strong directivity is generally the main channel for water intrusion.

[0070] Step S1, determining the optimized production wells based on the comprehensive permeability, storage volume ratio and fracture pointing strength coefficient of the production well test, includes:

[0071] Step A1: Create a correlation scatter plot with the formation coefficient (comprehensive permeability interpreted by well test, i.e., a comprehensive reflection of fracture, matrix, and effective reservoir thickness) as the ordinate and the storage-to-volume ratio as the abscissa;

[0072] Step A2: classify the flow category of the single well according to the linear law of the correlation scatter plot;

[0073] Step A3: Determine the optimized production wells based on the flow type and fracture orientation intensity coefficient of the single well.

[0074] In the embodiment of the present invention, taking the well test of the production well of the D gas reservoir as an example, the comprehensive permeability, storage volume ratio and fracture pointing strength of the well test of the production well of the D gas reservoir are statistically analyzed. According to the method of step A1, the correlation scatter plot is established as follows: Figure 3 As shown;

[0075] Based on the linear law of the correlation scatter plot (this law is based on big data statistics and combined with the water invasion characteristics of individual wells, the regions divided, such as the fracture-dominated region, are known to have production well test parameters and water invasion patterns that conform to the fracture advance characteristics. After taking the test data of unknown production wells, the parameters are placed on the chart to determine whether they also have fracture water invasion), the flow categories of individual wells are divided into homogeneous fracture network production wells and fracture-dominated production wells;

[0076] In step A3, the water invasion risk level is evaluated well by well based on the reservoir heterogeneity analysis and the fracture orientation intensity coefficient as the main parameter, because the speed of water invasion depends on the degree of fracture network cutting around the well and the size of the fracture-matrix range.

[0077] Therefore, combining the flow category and fault orientation intensity coefficient of a single well, the water intrusion risk level of the production well can be directly divided, and the production well with a high water intrusion risk level can be determined as the optimized production well.

[0078] The more fragmented and weakly directed fracture systems are, the higher the well test KH comprehensive permeability is, and the more uniform the water invasion is. For such production wells, production control is less affected by the water invasion rate, and the speed of water invasion is only affected by the overall gas production rate of the gas reservoir. For gas wells with single-fracture cutting and highly directed fracture systems, poor matrix properties, large ranges, and non-uniform water invasion, these are optimized production wells. Excessive production pressure differentials can cause rapid water channeling, resulting in large amounts of water-sealed gas, affecting gas well production and reservoir development.

[0079] In the production well of gas reservoir D, the present invention exemplarily divides the water invasion risk level of the production well into high risk, medium risk and low risk. The specific determination results are as follows: Figure 4 As shown, it is clear that the four wells including D5 have strong fracture seepage capacity, high storage capacity ratio, high fracture pointing strength coefficient and high fracture water channeling risk, and are optimized wells for production allocation;

[0080] In the embodiment of the present invention, taking D5 well as an example, Figure 5 Before optimization, the D5 well productivity and production change curve is as follows: Figure 5 As shown, from Figure 5The single well production curve of D5 well shown in the figure has many abnormal production stages caused by sand production or scaling in the wellbore. It is necessary to select the production stage that can truly reflect the bottom hole flowing pressure. The production stage that can truly reflect the bottom hole flowing pressure is as follows: Figure 5 In the production stages marked ①, ②, ③, ④, ⑤, ⑥, ⑦, and ⑧, the well sections with reaction flow pressure are counted, the gas production index, production pressure difference, and production allocation ratio are calculated, and a matrix-fracture gas supply coupling chart is established (i.e., step S2 is performed). The production allocation ratio is the ratio of daily production to open-flow rate;

[0081] Affected by matrix physical properties, fracture development degree and the matching relationship between the two, the production capacity and stable production capacity of production wells vary. Select a representative stable production section, make the production non-dimensional by allocating production proportions, and establish a correlation with the production pressure difference and gas production index. Two intersecting exponential curves are presented. This chart is the comprehensive production capacity of this well, which reflects the differences in reservoir, seepage and gas supply. Figure 6 and Figure 7 A good matrix-fracture coupling relationship shows the characteristics of high gas recovery index and low production pressure difference, while a poor coupling relationship shows the opposite.

[0082] Figure 6 This is the matrix-fracture gas supply coupling diagram of the production well in the western part of the D gas reservoir, showing poor matrix-fracture coupling relationship; Figure 7 This is the matrix-fracture gas supply coupling diagram of the eastern production well of gas reservoir D, showing a good matrix-fracture coupling relationship;

[0083] like Figure 6 and Figure 7 The eastern single-well production data are all to the right of the "intersection point" on the production capacity chart. They have high gas production indices, low pressure drop rates, low pressure loss under different production allocation conditions, and good matrix-fracture matching. The western reservoirs are mostly to the left of the "intersection point," with a poor balance between fracture seepage and matrix gas supply. The central reservoirs fall somewhere between the east and west. Well D5 is located in the western part of the gas reservoir. Finding a matrix-fracture gas supply balance is particularly important for suppressing water intrusion.

[0084] In step S3, the production allocation area for optimizing the production ratio of the production allocation wells is obtained based on the matrix-fracture gas supply coupling diagram, the critical water invasion pressure difference, and the energy loss reduction constraint, including:

[0085] Step B1: determining the critical edge and bottom water intrusion pressure difference based on the changes in the gas-liquid ratio, chloride radicals, and production pressure difference of the production well;

[0086] Step B2: determining energy loss reduction constraints based on the relationship between the production well gas production index and the pressure drop rate;

[0087] Step B3: Using the critical water invasion pressure difference and the reduction of capacity loss as constraint conditions, draw constraint lines on the single-well matrix-fracture gas supply coupling chart to obtain the production allocation area with the optimized production ratio of the allocated production wells;

[0088] In the embodiment of the present invention, according to step B1, the upper limit of the edge water inrush pressure difference of the D gas reservoir is determined to be 1.5-3.5 MPa, and the bottom water coning pressure difference is determined to be 2-3 MPa;

[0089] According to step B2, the actual bottom hole flowing pressure of well D5 is counted during the production phase, and the relationship between gas production index and pressure drop rate is regressed, as shown in the following example: Figure 8 As shown in the figure, there is an obvious inflection point. Optimizing the production pressure differential with high gas production index and low pressure drop rate is an effective way to maintain stable production and reduce energy loss.

[0090] According to step B3, the critical water invasion pressure difference and the reduction of capacity loss are used as the limiting conditions, and the limiting lines are drawn on the single well matrix-fracture gas supply coupling chart to obtain the production allocation area with the optimized production ratio of the allocated production wells, as shown in the following example: Figure 9 As shown in the gray area;

[0091] After the above steps S1-S3, the D5 well is optimized, the production is dimensionless through the production ratio, and the correlation is established with the production pressure difference and gas production index. Figure 8 As shown in the figure), it is believed that the gas production index is controlled at 150,000 cubic meters / MPa, the wellhead pressure drop rate can be lower than 0.3MPa / mon, and the stable production effect is better. At the same time, considering that the water pressure difference is less than 1.5MPa, the reasonable production allocation area is circled (such as Figure 9 As mentioned above), the comprehensive production of this well should be 200,000 cubic meters per day.

[0092] In mid-April 2022, water was observed in the D5 well, and the oil pressure and production dropped rapidly, while the daily water production rose rapidly to 70 cubic meters per day. After the production allocation method in the above embodiment was applied and the production was reduced to 270,000 cubic meters per day, the oil pressure and daily gas production gradually increased, while the daily water production decreased. Figure 10 This shows that the production allocation method based on production pressure difference and dynamic constraints can effectively reduce water intrusion and weaken fracture water-sealed gas.

[0093] like Figure 11 As shown, a production allocation system for developing a fractured water-bearing sandstone gas reservoir according to an embodiment of the present invention includes:

[0094] The determination module 1 is used to determine the optimized production wells based on the comprehensive permeability, storage volume ratio and fracture pointing strength coefficient of the production well test;

[0095] The chart establishment module 2 is used to establish a matrix-fracture gas supply coupling chart for the determined optimized production well;

[0096] The diagram module 3 is used to diagram the production area with the optimized production ratio of the production wells based on the matrix-fracture gas supply coupling diagram, the critical water invasion pressure difference, and the energy loss reduction constraint.

[0097] In the embodiment of the present invention, obtaining the fracture pointing intensity coefficient includes:

[0098] Based on the discrete fractures, the fracture permeability is coarsened into the grid using the Oda Block algorithm;

[0099] According to the roughened curve, the fracture pointing intensity coefficient is obtained.

[0100] In an embodiment of the present invention, the determination module includes a first submodule, a second submodule and a third submodule;

[0101] The first submodule is used to establish a correlation scatter plot with the logarithm of the comprehensive permeability as the vertical coordinate and the storage capacity ratio as the horizontal coordinate;

[0102] The second submodule is used to classify the flow categories of individual wells based on the linear law of the correlation scatter plot;

[0103] The third submodule is used to determine the optimized production wells based on the flow category and fracture pointing intensity coefficient of the single well.

[0104] In an embodiment of the present invention, the diagram module includes a fourth submodule, a fifth submodule, and a sixth submodule;

[0105] The fourth submodule is used to determine the critical invasion pressure difference of edge and bottom water based on the changes in the gas-liquid ratio, chloride radical and production pressure difference of the production well;

[0106] The fifth submodule is used to determine the energy loss reduction constraint based on the relationship between the production well gas production index and the pressure drop rate;

[0107] The sixth submodule is used to draw constraint lines on the single-well matrix-fracture gas supply coupling diagram, using the critical water intrusion pressure difference and the reduction of capacity loss as constraint conditions, to obtain the production allocation area that optimizes the production ratio of the allocated production wells. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will understand that the technical solutions described in the aforementioned embodiments may be modified or some of the technical features may be replaced by equivalents; such modifications or replacements do not deviate from the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for developing and allocating production of fractured water-bearing sandstone gas reservoirs, characterized in that: include: Determine the optimal production well allocation based on the comprehensive permeability, storage volume ratio and fracture pointing strength coefficient of the production well test; For the optimized production wells, a matrix-fracture gas supply coupling chart is established; Based on the matrix-fracture gas supply coupling diagram, as well as the critical water invasion pressure difference and energy loss reduction constraints, the production allocation area with optimized production ratio of the allocated production wells was graphically determined.

2. The method for developing and allocating production of fractured water-bearing sandstone gas reservoirs according to claim 1, characterized in that: The comprehensive permeability and storage-volume ratio are obtained from production well test data.

3. The method for developing and allocating production of fractured water-bearing sandstone gas reservoirs according to claim 1, characterized in that: The acquisition of the fracture pointing strength coefficient includes: Based on the discrete fractures, the fracture permeability is coarsened into the grid using the Oda Block algorithm; According to the roughened curve, the fracture pointing intensity coefficient is obtained.

4. The method for developing and allocating production of fractured water-bearing sandstone gas reservoirs according to claim 1, characterized in that: The method of determining the optimized production well allocation based on the comprehensive permeability, storage volume ratio and fracture pointing strength coefficient of the production well test includes: A correlation scatter plot is established with the logarithm of the comprehensive permeability as the ordinate and the storage capacity ratio as the abscissa; According to the linear law of the correlation scatter plot, the flow category of the single well is divided; The optimized production wells are determined based on the flow category of the single well and the fault pointing strength coefficient.

5. The method for developing and allocating production of fractured water-bearing sandstone gas reservoirs according to claim 4, characterized in that: The flow categories of the single well include homogeneous fracture network production wells and fracture-dominated production wells.

6. A method for developing and allocating production of fractured water-bearing sandstone gas reservoirs according to any one of claims 1 to 5, characterized in that: Based on the matrix-fracture gas supply coupling diagram, critical water invasion pressure difference, and energy loss reduction constraints, the production allocation area for optimizing the production ratio of the allocated production wells is illustrated, including: Determine the critical invasion pressure difference of edge and bottom water based on the changes in gas-liquid ratio, chloride radical and production pressure difference of production wells; Determine the energy loss reduction constraint based on the relationship between the production well gas production index and the pressure drop rate; Taking the critical water invasion pressure difference and the reduction of capacity loss as the limiting conditions, a limiting line is drawn on the single-well matrix-fracture gas supply coupling chart to obtain the production allocation area with the optimized production ratio of the allocated production wells.

7. A production allocation system for the development of fractured water-bearing sandstone gas reservoirs, characterized in that: include: The determination module is used to determine the optimized production wells based on the comprehensive permeability, storage volume ratio and fracture pointing strength coefficient of the production well test; Establish a chart module to establish a matrix-fracture gas supply coupling chart for the determined optimized production wells; The graphical module is used to illustrate the production allocation area based on the matrix-fracture gas supply coupling diagram, critical water invasion pressure difference, and energy loss reduction constraints to optimize the production ratio of the allocated production wells.

8. A production allocation system for developing fractured water-bearing sandstone gas reservoirs according to claim 7, characterized in that: The acquisition of the fracture pointing strength coefficient includes: Based on the discrete fractures, the fracture permeability is coarsened into the grid using the Oda Block algorithm; According to the roughened curve, the fracture pointing intensity coefficient is obtained.

9. The production allocation system for developing fractured water-bearing sandstone gas reservoirs according to claim 7, characterized in that: The determination module includes a first submodule, a second submodule and a third submodule; The first submodule is used to establish a correlation scatter plot with the logarithm of the comprehensive permeability as the vertical coordinate and the storage capacity ratio as the horizontal coordinate; The second submodule is used to classify the flow categories of individual wells based on the linear law of the correlation scatter plot; The third submodule is used to determine the optimized production wells based on the flow category and fracture pointing intensity coefficient of the single well.

10. A production allocation system for developing fractured water-bearing sandstone gas reservoirs according to any one of claims 7 to 9, characterized in that: The diagram module includes a fourth submodule, a fifth submodule and a sixth submodule; The fourth submodule is used to determine the critical invasion pressure difference of edge and bottom water based on the changes in the gas-liquid ratio, chloride radical and production pressure difference of the production well; The fifth submodule is used to determine the energy loss reduction constraint based on the relationship between the production well gas production index and the pressure drop rate; The sixth submodule is used to use the critical water invasion pressure difference and the reduction of capacity loss as constraint conditions, draw constraint lines on the single-well matrix-fracture gas supply coupling map, and obtain the production allocation area with the optimized production ratio of the allocated production wells.

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