Gas storage gas production prediction method and system based on historical data mining

Abstract

The invention discloses a gas storage gas production prediction method and system based on historical data mining, and belongs to the field of natural gas underground gas storage construction and operation. According to the method, the change rule among the gas production amount, the formation pressure and the wellhead pressure of the gas storage in gas production operation over the years and the formation pressure of the gas storage every day are summarized, and the daily gas production amount of all gas wells of the gas storage, the average oil pressure produced by all the gas wells every day and the formation pressure of the gas storage every day are combined; establishing a mathematical model of the gas reservoir yield, the production oil pressure and the formation pressure, and obtaining the gas production wellhead pressure, the formation pressure after gas production, the daily gas production rate and the accumulated daily gas production rate according to the mathematical model, so as to realize gas production prediction. Therefore, the experience prediction gas production method based on the gas storage gas production historical rule effectively guides the gas storage peak gas production allocation in winter, can effectively judge whether the gas produced by the gas storage has the leakage or overflow risk or not, provides a reliable evaluation method for the safe operation of the gas storage, and provides technical support for the gas storage gas production peak regulation design.

Description

Technical Field

[0001] The present invention belongs to the field of construction and operation of natural gas underground storage, and relates to a method and system for predicting gas production in gas storage based on historical data mining, and specifically to a method for using parameters such as formation pressure before and after gas production in gas storage over the years, gas wellhead pressure, and daily gas production to establish a regular relationship between the parameters, and predict parameters such as average gas wellhead pressure, daily gas production, and remaining formation pressure during gas production in gas storage in combination with the gas production pressure drop law and production stage characteristic evaluation. Background Art

[0002] Gas storage generally refers to the use of existing underground storage space. Natural gas is injected into the gas storage for storage during the off-season and quickly taken out during the peak season, which plays an important role in regulating the balance of natural gas supply and demand. The annual gas production peak-shaving prediction of the gas storage is an important task of the gas storage. It is difficult to predict the gas production peak-shaving of the gas storage due to the influence of the gas storage capacity, gas well gas production capacity, peak-shaving system and gas production time. The combined gas reservoir pressure drop equation and gas well production capacity equation are used to predict the cumulative gas production under the formation pressure condition in the later stage. This method requires accurate calculation of parameters such as gas storage capacity and gas production capacity. It is difficult to accurately predict the gas production peak-shaving of the gas storage in winter, and it is impossible to predict the changing trend of parameters such as gas wellhead pressure, and it is impossible to guide the peak-shaving gas production of the gas storage. Summary of the invention

[0003] The purpose of the present invention is to solve the problems in the prior art that it is difficult to accurately predict the peak gas production of gas reservoirs in winter, and it is impossible to predict the changing trends of parameters such as the gas wellhead pressure, and it is impossible to guide the peak gas production of gas storage reservoirs. A method and system for predicting gas production in gas storage reservoirs based on historical data mining is provided.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] The present invention proposes a method for predicting gas production in a gas storage facility based on historical data mining, comprising the following steps:

[0006] Obtain the formation pressure before and after gas production, and obtain the formation pressure of the gas reservoir every day according to the cumulative gas production of the gas reservoir in each cycle, the formation pressure before and after gas production;

[0007] According to the daily gas production of all gas wells in the gas storage, the average oil pressure of all gas wells produced every day and the daily formation pressure of the gas storage, a mathematical model of gas storage production, production oil pressure and formation pressure is established;

[0008] According to the mathematical model of gas reservoir output, production oil pressure and formation pressure, the wellhead pressure and daily gas production in the gas production decline stage are obtained, and the formation pressure after gas production is obtained according to the daily gas production in the gas production decline stage;

[0009] Based on the wellhead pressure, formation pressure after gas production, daily gas production and cumulative daily gas production, the gas production process curve is obtained to realize the gas storage reservoir gas production prediction.

[0010] Preferably, the formation pressure P before gas production is obtained e0 The method is as follows:

[0011]

[0012] Where H is the depth from the wellhead to the middle of the gas layer, T is the average temperature of the static gas column in the wellbore, T = (T wh +T e ) / 2, Z is the average deviation coefficient of the wellbore static gas column; γ g is the relative density of natural gas.

[0013] Preferably, the formation pressure after gas production is P en The method is as follows:

[0014]

[0015] Where H is the depth from the wellhead to the middle of the gas layer, T is the average temperature of the static gas column in the wellbore, T = (T wh +T e ) / 2,T e is the formation temperature, T wh The wellhead temperature of produced gas, Z is the average deviation coefficient of the static gas column in the wellbore; γ g is the relative density of natural gas.

[0016] Preferably, the formation pressure P of the gas reservoir is obtained every day. ei The method is as follows:

[0017] P ei =β×Q i +ω

[0018] Among them, β is the formation pressure drop required for unit gas production, ω is the formation pressure before gas production, and i has a value range of (0-n).

[0019] Preferably, the formation pressure drop required for unit gas production is

[0020] Preferably, a mathematical model of gas reservoir output, production oil pressure, and formation pressure is established as follows:

[0021]

[0022] Among them, a, b, and c are all empirical parameters of the regression relationship formula of multi-period gas production data; P whi is the gas wellhead pressure, q i It is the daily gas production of the gas storage.

[0023] Preferably, the gas wellhead pressure P whi Equal to the minimum gas wellhead pressure P min When , stable gas production ends.

[0024] The present invention proposes a gas storage reservoir gas production prediction system based on historical data mining, comprising:

[0025] A formation pressure acquisition module, which is used to acquire the formation pressure before and after gas production, and acquire the formation pressure of the gas reservoir every day according to the cumulative gas production of the gas reservoir in each cycle, the formation pressure before and after gas production;

[0026] A mathematical model building module, which is used to build a mathematical model of gas reservoir output, production oil pressure, and formation pressure based on the daily gas production of all gas wells in the gas storage reservoir, the average oil pressure of all gas wells produced every day, and the daily formation pressure of the gas reservoir;

[0027] A gas production parameter acquisition module, which is used to obtain the gas wellhead pressure and the daily gas production volume in the gas production decline stage according to the mathematical model of the gas reservoir output, production oil pressure and formation pressure, and to obtain the formation pressure after gas production according to the daily gas production volume in the gas production decline stage;

[0028] The gas production process curve acquisition module is used to obtain the gas production process curve based on the gas production wellhead pressure, the formation pressure after gas production, the daily gas production and the cumulative daily gas production, so as to realize the gas production prediction of the gas storage.

[0029] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of a gas storage reservoir gas production prediction method based on historical data mining when executing the computer program.

[0030] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of a gas storage reservoir gas production prediction method based on historical data mining.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The present invention proposes a gas storage reservoir gas production prediction method based on historical data mining, which summarizes the change rules between the gas production volume, formation pressure and wellhead pressure in the gas production operation of the gas storage over the years, the formation pressure of the gas storage every day, and combines the daily gas production of all gas wells in the gas storage, the average oil pressure of all gas wells produced every day and the formation pressure of the gas storage every day, to establish a mathematical model of gas storage production and production oil pressure, and formation pressure, and obtains the gas production wellhead pressure, formation pressure after gas production, daily gas production and cumulative daily gas production according to the mathematical model, so as to realize gas production prediction. Therefore, the empirical prediction gas production method based on the historical law of gas storage gas production established by the present invention effectively guides the gas storage winter peak gas production allocation, and can effectively judge whether there is a risk of leakage or spillage of the gas produced by the gas storage, and provide a reliable evaluation method for the safe operation of the gas storage. Provide technical support for the gas production peak regulation design of the gas storage, monitor the gas production operation of the gas storage, provide gas production safety warning, and ensure the safe and stable gas production of the gas storage.

[0033] The present invention proposes a gas storage reservoir gas production prediction system based on historical data mining, which is divided into a formation pressure acquisition module, a mathematical model establishment module, a gas production parameter acquisition module and a gas production process curve acquisition module to realize gas storage reservoir gas production prediction. The modularization concept is adopted to make each module independent of each other, which is convenient for unified management of each module. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 This is a flow chart of the gas storage gas production prediction method based on historical data mining of the present invention.

[0036] Figure 2 This is an overall gas production operation curve diagram of a gas storage facility of the present invention.

[0037] Figure 3 It is a curve diagram showing the relationship between the formation pressure difference before and after gas production and the cumulative gas production volume of the present invention.

[0038] Figure 4 It is the actual data and fitting curve diagram of the Shaanxi 224 gas storage reservoir of the present invention.

[0039] Figure 5 This is a parameter prediction curve diagram of the stable gas production process of the gas storage of the present invention.

[0040] Figure 6 It is a parameter prediction curve diagram of the gas storage gas production decline process of the present invention.

[0041] Figure 7 It is a parameter prediction curve diagram of the whole process of gas production in the gas storage of the present invention.

[0042] Figure 8 This is a comparison chart of the predicted and actual gas injection parameters of a gas storage facility in 2020 of the present invention.

[0043] Fig. 9 This is a diagram of the gas storage gas production prediction system based on historical data mining of the present invention. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions 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 part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0045] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0047] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0048] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0049] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0051] The present invention proposes a method for predicting gas production in a gas storage facility based on historical data mining, such as Figure 1 As shown, the following steps are included:

[0052] S1. Obtain the formation pressure before and after gas production, and obtain the formation pressure of the gas reservoir every day according to the cumulative gas production of the gas reservoir in each cycle, the formation pressure before and after gas production;

[0053] Get the formation pressure P before gas production e0 The method is as follows:

[0054]

[0055] Formation pressure after gas production P en The method is as follows:

[0056]

[0057] Where H is the depth from the wellhead to the middle of the gas layer, T is the average temperature of the static gas column in the wellbore, T = (T wh +T e ) / 2, Z is the average deviation coefficient of the wellbore static gas column; γ g is the relative density of natural gas.

[0058] Get the daily formation pressure P of the gas reservoir ei The method is as follows:

[0059] P ei =β×Q i +ω

[0060] Among them, β is the formation pressure drop required for unit gas production, ω is the formation pressure before gas production, and i has a value range of (0-n).

[0061] The required formation pressure drop per unit gas production

[0062] S2. Establish a mathematical model of gas reservoir output, production oil pressure and formation pressure based on the daily gas production of all gas wells in the gas storage reservoir, the average oil pressure of all gas wells produced every day and the daily formation pressure of the gas storage reservoir;

[0063] The mathematical model of gas reservoir output, production oil pressure and formation pressure is established as follows:

[0064]

[0065] Among them, a, b, and c are all empirical parameters of the regression relationship formula of multi-period gas production data; P whi is the gas wellhead pressure, q i It is the daily gas production of the gas storage.

[0066] S3. According to the mathematical model of gas reservoir output, production oil pressure and formation pressure, the wellhead pressure and the daily gas production volume in the gas production decline stage are obtained, and the formation pressure after gas production is obtained according to the daily gas production volume in the gas production decline stage;

[0067] Gas wellhead pressure P whi Equal to the minimum gas wellhead pressure P min When , stable gas production ends.

[0068] S4. Based on the wellhead pressure, formation pressure after gas production, daily gas production and cumulative daily gas production, the gas production process curve is obtained to realize the gas production prediction of the gas storage.

[0069] The specific steps include:

[0070] Step 1: Analyze the gas production curve of the gas storage. As the gas storage produces gas stably, the formation pressure P ei Reduce the gas wellhead pressure P whi Then it gradually decreases; when the wellhead pressure P whi Reduce to the minimum wellhead pressure P for gas production min After that, the daily gas production q i According to the gas production curve of the gas storage reservoir, the gas production process is divided into two stages: stable gas production and gas production decline.

[0071] Step 2: Balance the wellhead pressure P before gas extraction in the gas reservoir over the years wh0 , Balanced wellhead pressure P of gas reservoir after gas extraction over the years whn , using the formation static pressure calculation formula, the formation pressure P before gas production can be evaluated e0 , Formation pressure after gas production P en ;

[0072]

[0073]

[0074] Where H is the depth from the wellhead to the middle of the gas layer, T is the average temperature of the static gas column in the wellbore, T = (T wh +T e ) / 2,T e is the formation temperature, T wh The wellhead temperature of produced gas, Z is the average deviation coefficient of the static gas column in the wellbore; γ g is the relative density of natural gas;

[0075] Step 3: Based on the cumulative gas production Q of the gas reservoir per cycle n and the formation pressure before gas production P e0 , Formation pressure after gas production P en The data can be regressed to obtain the characteristic curve of the relationship between the cumulative gas production over the years and the formation pressure drop, which obeys the linear law and calculates the formation pressure P of the gas reservoir every day. ei .

[0076]

[0077] P ei =β×Q i +ω (Formula 4)

[0078] Where: β is the formation pressure drop required for unit gas production; ω is the formation pressure P before gas production e0 ; i value range (0-n);

[0079] Step 4: Based on the daily gas production of all gas wells in the gas storage facility over the years, i 、The average oil pressure P of all gas wells produced every day whi and the daily formation pressure P of the gas reservoir ei The daily gas production q can be obtained by i and The relationship curve was obtained by regression, and the relationship formula between gas reservoir production and production oil pressure and formation pressure was established (Formula 5).

[0080]

[0081] Where: a, b, c values ​​are empirical parameters of the multi-period gas production data regression relationship formula;

[0082] Step 5: In the stable gas production stage: the average wellhead pressure P of the old well shut-in before gas production gwh0 It can be read from the wellhead oil pressure gauge. According to step 2, the formation pressure P before gas production can be calculated. e0 ; Designed daily gas production of gas storage q i is a constant, the cumulative gas production Q on the i-th day can be obtained i According to the relationship in step 3, the formation pressure P on the i-th day can be calculated ei Using the relationship in step 4, the gas wellhead pressure P on the i-th day can be calculatedwhi By iterating steps 3 and 4 repeatedly, we can get the wellhead pressure P of the gas storage every day. whi , formation pressure P ei ; When the gas wellhead pressure P whi Equal to the minimum gas wellhead pressure P min , the calculation of this phase ends.

[0083] Step 6: In the gas production decline stage: At the minimum wellhead pressure P min , the formation pressure P calculated in step 5 ei-1 Under known conditions, using step 4, the daily gas production volume q of the gas reservoir during the gas production decline stage can be calculated i According to step 3, the formation pressure P after gas production on the i-th day can be calculated ei By repeatedly iterating steps 4 and 3, we can get the daily gas production of the gas storage q i , formation pressure P ei ; This stage is calculated until the end of the gas injection period.

[0084] Step 7: Combining steps 5 and 6, we can get the gas storage wellhead pressure P whi , formation pressure P ei , daily gas production q i , Cumulative gas production Q i Etc., the entire gas production process curve of the gas storage can be drawn to predict the gas production volume.

[0085] Example

[0086] The gas production relationship of the actual gas storage gas production operation parameters is used to regress the gas production relationship to predict the overall gas production process parameters of the gas storage. The method described in this example mainly includes the following steps:

[0087] Step 1: Based on the dynamic law of gas extraction in a gas storage reservoir ( Figure 2 ), and the formation pressure P is obtained ei Cumulative gas production Q i The decreasing law relationship P ei =5.547×Qi+33.476

[0088] Step 2: Based on the daily gas production q i and The relationship curve ( Figure 3 ), the relation:

[0089]

[0090] Step 3: If Figure 4 It is known that the formation pressure before gas production in the gas reservoir is 34.0MPa, and the minimum wellhead pressure for gas production is 6.4MPa. According to the stable gas production design of 3-3.5-4 million cubic meters per day, the daily cumulative gas production Q can be calculated.i According to step 2, the daily residual formation pressure P can be calculated ei According to step 3, the daily gas wellhead pressure P can be calculated. whi Repeat steps 2 and 3 until the wellhead pressure is equal to 6.4 MPa, and then end the calculation. The formation pressure at the end of stable gas production is 20.98 MPa ( Figure 5 ).

[0091] Step 4: When the minimum wellhead pressure is equal to P min =6.4MPa, stable formation pressure at the end of gas production P ei =20.98MPa. Using the relationship in step 3, the daily gas production volume q of the gas storage reservoir during the gas production decline stage can be calculated. i According to the relationship in step 2, the formation pressure P after gas production on the i-th day can be calculated ei By repeatedly iterating steps 3 and 2, we can get the daily gas production of the gas storage q i , formation pressure P ei ; Until the end of the gas production period ( Figure 6 ).

[0092] Step 5: Combining steps 3 and 4, we can get the gas production curves of the stable gas production stage and the gas production decreasing stage. Combining the two, we can get the gas production curve of the gas storage for 120 days, and predict the gas production volume ( Figure 7 ).

[0093] For the gas production of a gas storage in 2022, this method is used to calculate the gas production parameters of the two stages of stable gas production and gas production decline. The calculated daily gas production and cumulative gas production of the gas storage are highly consistent with the actual gas production, which can be used for gas storage gas production monitoring ( Figure 8 ).

[0094] The present invention proposes a gas storage reservoir gas production prediction system based on historical data mining, such as Fig. 9 As shown, it includes a formation pressure acquisition module, a mathematical model building module, a gas production parameter acquisition module and a gas production process curve acquisition module;

[0095] The formation pressure acquisition module is used to acquire the formation pressure before and after gas production, and acquire the formation pressure of the gas reservoir every day according to the cumulative gas production of the gas reservoir in each cycle, the formation pressure before and after gas production;

[0096] The mathematical model building module is used to build a mathematical model of gas reservoir output, production oil pressure and formation pressure according to the daily gas production of all gas wells in the gas storage reservoir, the average oil pressure of all gas wells produced every day and the formation pressure of the gas reservoir every day;

[0097] The gas production parameter acquisition module is used to obtain the gas wellhead pressure and the daily gas production volume in the gas production decline stage according to the mathematical model of the gas reservoir output, production oil pressure and formation pressure, and obtain the formation pressure after gas production according to the daily gas production volume in the gas production decline stage;

[0098] The gas production process curve acquisition module is used to obtain the gas production process curve based on the gas production wellhead pressure, the formation pressure after gas production, the daily gas production and the cumulative daily gas production, so as to realize the gas production prediction of the gas storage.

[0099] The terminal device provided in an embodiment of the present invention comprises: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps in the above-mentioned method embodiments are implemented. Alternatively, when the processor executes the computer program, the functions of the modules / units in the above-mentioned device embodiments are implemented.

[0100] The computer program may be divided into one or more modules / units, and the one or more modules / units are stored in the memory and executed by the processor to accomplish the present invention.

[0101] The terminal device may be a computing device such as a desktop computer, a notebook, a PDA, a cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0102] The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0103] The memory may be used to store the computer programs and / or modules, and the processor implements various functions of the terminal device by running or executing the computer programs and / or modules stored in the memory and calling the data stored in the memory.

[0104] If the module / unit integrated in the terminal device is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0105] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for predicting gas production in a gas storage facility based on historical data mining, characterized in that: The steps include: Obtain the formation pressure before and after gas production, and obtain the formation pressure of the gas reservoir every day according to the cumulative gas production of the gas reservoir in each cycle, the formation pressure before and after gas production; According to the daily gas production of all gas wells in the gas storage, the average oil pressure of all gas wells produced every day and the daily formation pressure of the gas storage, a mathematical model of gas storage production, production oil pressure and formation pressure is established; According to the mathematical model of gas reservoir output, production oil pressure and formation pressure, the wellhead pressure and daily gas production in the gas production decline stage are obtained, and the formation pressure after gas production is obtained according to the daily gas production in the gas production decline stage; Based on the wellhead pressure, formation pressure after gas production, daily gas production and cumulative daily gas production, the gas production process curve is obtained to realize the gas storage reservoir gas production prediction.

2. The method for predicting gas production in a gas storage facility based on historical data mining according to claim 1, characterized in that: Get the formation pressure P before gas production e0 The method is as follows: Where H is the depth from the wellhead to the middle of the gas layer, T is the average temperature of the static gas column in the wellbore, T = (T wh +T e ) / 2, Z is the average deviation coefficient of the wellbore static gas column; γ g is the relative density of natural gas.

3. The method for predicting gas production in a gas storage facility based on historical data mining according to claim 1, characterized in that: Formation pressure after gas production P en The method is as follows: Where H is the depth from the wellhead to the middle of the gas layer, T is the average temperature of the static gas column in the wellbore, T = (T wh +T e ) / 2,T e is the formation temperature, T wh The wellhead temperature of produced gas, Z is the average deviation coefficient of the static gas column in the wellbore; γ g is the relative density of natural gas.

4. The method for predicting gas production in a gas storage facility based on historical data mining according to claim 1, characterized in that: Get the daily formation pressure P of the gas reservoir ei The method is as follows: P ei =β×Q i +oh Among them, β is the formation pressure drop required for unit gas production, ω is the formation pressure before gas production, and i has a value range of (0-n).

5. The method for predicting gas production in a gas storage facility based on historical data mining according to claim 4 is characterized in that: The required formation pressure drop per unit gas production 6. The method for predicting gas production in a gas storage facility based on historical data mining according to claim 1, characterized in that: The mathematical model of gas reservoir output, production oil pressure and formation pressure is established as follows: Among them, a, b, and c are all empirical parameters of the regression relationship formula of multi-period gas production data; P whi is the gas wellhead pressure, q i It is the daily gas production of the gas storage.

7. The method for predicting gas production in a gas storage facility based on historical data mining according to claim 1, characterized in that: Gas wellhead pressure P whi Equal to the minimum gas wellhead pressure P min When , stable gas production ends.

8. A gas storage reservoir gas production prediction system based on historical data mining, characterized in that: include: A formation pressure acquisition module, which is used to acquire the formation pressure before and after gas production, and acquire the formation pressure of the gas reservoir every day according to the cumulative gas production of the gas reservoir in each cycle, the formation pressure before and after gas production; A mathematical model building module, which is used to build a mathematical model of gas reservoir output, production oil pressure, and formation pressure based on the daily gas production of all gas wells in the gas storage reservoir, the average oil pressure of all gas wells produced every day, and the daily formation pressure of the gas reservoir; A gas production parameter acquisition module, which is used to obtain the gas wellhead pressure and the daily gas production volume in the gas production decline stage according to the mathematical model of the gas reservoir output, production oil pressure and formation pressure, and to obtain the formation pressure after gas production according to the daily gas production volume in the gas production decline stage; The gas production process curve acquisition module is used to obtain the gas production process curve based on the gas production wellhead pressure, the formation pressure after gas production, the daily gas production and the cumulative daily gas production, so as to realize the gas production prediction of the gas storage.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method for predicting gas production in a gas storage facility based on historical data mining 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 the method for predicting gas production in a gas storage facility based on historical data mining as described in any one of claims 1 to 7 are implemented.

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