Method, device and equipment for layered evaluation of productivity of multi-layer commingled recovery gas well and medium

Abstract

The invention discloses a productivity layering evaluation method, device and equipment for a multi-layer commingled recovery gas well and a medium. The method comprises the steps that the effective sand body area of each layer section is determined; according to the effective sand body area of each layer section and the discharge radius of the reference layer section, the discharge radiuses of other layer sections are determined, and the dynamic reserves of each layer section are determined; according to the wellhead oil pressure data, the bottom hole flowing pressure of each layer section is determined; according to the drainage radius of each layer section, the dynamic reserves of each layer section, the pseudo-pressure function matched with the flowing bottomhole pressure of each layer section and the formation pressure of each layer section on the initial day, the daily gas production rate estimated value of each layer section is determined; and if the error between the daily gas production rate estimated value and the target daily gas production rate measured value meets a precision condition, determining a layering evaluation result of the target gas well according to the obtained drainage radius, the dynamic reserves and the daily gas production rate estimated value. According to the scheme, the problem that the productivity layering evaluation accuracy of the multi-layer commingled recovery gas well is low is solved, gas well yield layering splitting is achieved, and the reliability of evaluation factors is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of natural gas reservoir development, and particularly relates to a method and device for evaluating the productivity of a multi-layer commingled gas well, an electronic device and a storage medium. BACKGROUND

[0002] In the development of Sulige-type tight sandstone gas reservoirs, multiple sets of effective sand bodies are developed vertically, and the effective sand bodies are in the form of lenses, and the effective sand bodies have the characteristics of small scale, thin thickness and poor connectivity. In the development of the gas reservoir, in order to improve the single-well production, multiple gas layers are often shot vertically at the same time. However, in the production process, in order to save production costs, only the single-well wellhead production and casing pressure are measured, and no pressure gauges and flowmeters are configured under each small layer, so that the accurate splitting of the production of each small layer in the vertical direction cannot be realized. However, the production layer splitting is an important basis for evaluating the dynamic reserves, drainage radius and remaining gas distribution of the gas well.

[0003] At present, the existing production layer splitting method of the multi-layer commingled gas well includes: (1) formation coefficient method, which takes the ratio of the Kh value of each small layer to the total Kh value of all layers as the fixed gas production contribution rate of each small layer. This method is simple in calculation process, but the gas production contribution rate of each small layer is affected by multiple factors, and only the Kh value is used to constrain the gas production contribution rate of each small layer, which is too single in consideration of factors, and has large calculation error. (2) Production profile testing method, which measures the production of each small layer. However, this method has high cost and can only measure for a short time, and the data is discontinuous and affects the normal production of the gas well. (3) Catastrophe theory method, which uses topology as a tool and structural stability theory as a basis to study the catastrophe phenomenon of uncertain systems with multiple influencing factors. Although this method considers multiple factors, it is based only on mathematical statistical analysis and lacks the theoretical basis of gas reservoir engineering.

[0004] Based on the above defects of the prior art, there is an urgent need for a production layer evaluation method of a multi-layer commingled gas well to realize the production layer splitting of the gas well and improve the accuracy of evaluation factors such as the production of each small layer, the drainage radius and the dynamic reserves. SUMMARY

[0005] The present application provides a production layer evaluation method, device, equipment and storage medium of a multi-layer commingled gas well to solve the problem of low accuracy of production layer evaluation of the multi-layer commingled gas well, realize the production layer splitting of the gas well and improve the reliability of evaluation factors such as the production of each small layer, the drainage radius and the dynamic reserves.

[0006] According to an aspect of the present application, a production layer evaluation method of a multi-layer commingled gas well is provided, and the method comprises:

[0007] obtaining the effective sand body thickness data associated with the target gas well, the pre-fitted thickness-length relationship of the effective sand body and the pre-fitted thickness-width relationship of the effective sand body.

[0008] determine effective sand body areas of each interval of the target gas well according to the effective sand body thickness data, the thickness-length relationship and the thickness-width relationship;

[0009] determine drainage radii of intervals other than the reference interval according to the effective sand body areas of the intervals and the drainage radius of the reference interval, and determine dynamic reserves of the intervals according to the drainage radii of the intervals;

[0010] determine well bottom flow pressures of the intervals according to the well head oil pressure data obtained in advance;

[0011] determine daily gas production estimation values of the intervals according to the drainage radii of the intervals, the dynamic reserves of the intervals, the pseudo-pressure function matched with the well bottom flow pressures of the intervals and the formation pressures of the intervals on the initial day;

[0012] determine a gas production error according to the daily gas production estimation values of the intervals and the measured daily gas production values of the target gas well obtained in advance;

[0013] if the gas production error meets a preset precision condition, determine a layered evaluation result of the target gas well according to the drainage radii of the intervals, the dynamic reserves of the intervals and the daily gas production estimation values of the intervals.

[0014] According to another aspect of the present application, a device for evaluating productivity of each interval of a multi-layer commingled gas well is provided, and the device comprises:

[0015] a data obtaining module for obtaining effective sand body thickness data associated with a target gas well, a thickness-length relationship of the effective sand body fitted in advance and a thickness-width relationship of the effective sand body fitted in advance;

[0016] a sand body area determining module for determining effective sand body areas of each interval of the target gas well according to the effective sand body thickness data, the thickness-length relationship and the thickness-width relationship;

[0017] a radius and reserve determining module for determining drainage radii of intervals other than a reference interval according to the effective sand body areas of the intervals and the drainage radius of the reference interval, and determining dynamic reserves of the intervals according to the drainage radii of the intervals;

[0018] a well bottom flow pressure determining module for determining well bottom flow pressures of the intervals according to well head oil pressure data obtained in advance;

[0019] a daily gas production estimating module for determining daily gas production estimation values of the intervals according to the drainage radii of the intervals, the dynamic reserves of the intervals, a pseudo-pressure function matched with the well bottom flow pressures of the intervals and formation pressures of the intervals on an initial day;

[0020] a gas production error determination module configured to determine a gas production error according to the daily gas production estimation value of each layer section and a daily gas production measured value of the target gas well obtained in advance;

[0021] a first evaluation result determination module configured to determine a layered evaluation result of the target gas well according to the drainage radius of each layer section, the dynamic reserves of each layer section and the daily gas production estimation value of each layer section if the gas production error meets a preset accuracy condition.

[0022] According to another aspect of the present application, an electronic device is provided, which comprises:

[0023] at least one processor; and a memory connected to the at least one processor in communication; wherein the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor to enable the at least one processor to perform the productivity layered evaluation method of the multi-layer commingled gas well according to any one of the embodiments of the present application.

[0024] According to another aspect of the present application, a computer readable storage medium is provided, which stores computer instructions for enabling a processor to implement the productivity layered evaluation method of the multi-layer commingled gas well according to any one of the embodiments of the present application when executed by the processor.

[0025] The technical scheme of the embodiments of the present application determines the effective sand body area of each layer section of the target gas well according to the effective sand body thickness data associated with the target gas well, the thickness-length relationship of the effective sand body fitted in advance and the thickness-width relationship of the effective sand body fitted in advance, determines the drainage radius of other layer sections except the reference layer section according to the effective sand body area of each layer section and the drainage radius of the reference layer section set in advance, determines the dynamic reserves of each layer section according to the drainage radius of each layer section, determines the daily gas production estimation value of each layer section according to the wellhead oil pressure data obtained in advance, determines the gas production error according to the daily gas production estimation value of each layer section and the daily gas production measured value of the target gas well obtained in advance, and determines the layered evaluation result of the target gas well according to the drainage radius of each layer section, the dynamic reserves of each layer section and the daily gas production estimation value of each layer section if the gas production error meets a preset accuracy condition. The technical scheme solves the problem of low accuracy of the productivity layered evaluation of the multi-layer commingled gas well, realizes the layered splitting of the gas well production, and improves the reliability of the evaluation factors such as the layered gas production, the drainage radius and the dynamic reserves.

[0026] It is to be understood that the details set forth in the description contained herein do not limit the scope of the application. Other embodiments of the application will be readily apparent to those skilled in the art from the description herein. It should be understood that the description and drawings are illustrative of the various embodiments and are not intended to limit the scope of the application. Various embodiments of the application will now be described, by way of example only, with reference to the drawings, in which: BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort based on these drawings.

[0028] Figure 1 is a flow chart of a method for evaluating the productivity of each layer of a multi-layered commingled gas well according to an embodiment of the present application;

[0029] Figure 2 is a flow chart of a method for evaluating the productivity of each layer of a multi-layered commingled gas well according to an embodiment of the present application;

[0030] Figure 3 is a structural schematic diagram of a device for evaluating the productivity of each layer of a multi-layered commingled gas well according to an embodiment of the present application;

[0031] Figure 4 is a structural schematic diagram of an electronic device for implementing the method for evaluating the productivity of each layer of a multi-layered commingled gas well according to an embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to make the technical personnel in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, but not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without any creative effort should be within the scope of protection of the present application.

[0033] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and in the above drawings are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices. The acquisition, storage, use, processing and other data in the technical solutions of the present application comply with the relevant provisions of national laws and regulations.

[0034] Embodiment one

[0035] Figure 1 A flowchart of a method for evaluating the productivity of a multi-layer combined gas well is provided for the first embodiment of the present application. This embodiment can be applied to the productivity evaluation of a multi-layer combined gas well in a tight sand gas reservoir of the Sulige type. The method can be executed by a device for evaluating the productivity of a multi-layer combined gas well, which can be realized in the form of hardware and / or software, and can be configured in an electronic device. As shown in Figure 1 The method comprises the following steps:

[0036] S110, obtaining the effective sand thickness data associated with the target gas well, the pre-fitted thickness-length relationship of the effective sand, and the pre-fitted thickness-width relationship of the effective sand.

[0037] The present scheme can be executed by a computer, a server or other electronic devices. The electronic device can obtain the thickness data, length data and width data of the effective sand associated with the target gas well through a gas well management platform. The target gas well can be a multi-layer combined gas well in a tight sand gas reservoir of the Sulige type to be evaluated. The thickness data, length data and width data of the effective sand associated with the target gas well can be the thickness data, length data and width data of the effective sand of a gas well of the same gas reservoir type, which can be used to characterize the thickness-length relationship and thickness-width relationship of the effective sand of the same gas reservoir type.

[0038] The electronic device can obtain the thickness-length relationship of the effective sand body by data fitting the thickness data of the effective sand body with the length data. The electronic device can obtain the thickness-width relationship of the effective sand body by data fitting the thickness data of the effective sand body with the width data. It can be understood that the thickness and length of the effective sand body, and the thickness and width of the effective sand body, are in an exponential relationship. The electronic device can perform data fitting on the thickness data and length data of the effective sand body, and the thickness data and width data of the effective sand body, respectively, according to the exponential relationship, to obtain the thickness-length relationship and the thickness-width relationship.

[0039] S120, determining the effective sand body area of each layer of the target gas well according to the effective sand body thickness data, the thickness-length relationship, and the thickness-width relationship.

[0040] After obtaining the thickness data of the effective sand body, the thickness-length relationship, and the thickness-width relationship, the electronic device can calculate the effective sand body length data of each layer of the target gas well according to the effective sand body thickness data, in combination with the thickness-length relationship. The electronic device can calculate the effective sand body width data of each layer of the target gas well based on the effective sand body thickness data and the thickness-width relationship. The effective sand body area can be determined based on the product of the effective sand body thickness and length. The electronic device can calculate the effective sand body area of each layer of the target gas well according to the effective sand body length data and the effective sand body width data of each layer of the target gas well.

[0041] S130, determining the drainage radius of each layer except the reference layer according to the effective sand body area of each layer and the pre-set drainage radius of the reference layer, and determining the dynamic reserves of each layer according to the drainage radius of each layer.

[0042] Since the effective sand bodies in the Sulige-type tight sandstone gas reservoir are mostly scattered and isolated, the effective sand bodies are small in size and poor in continuity, and are in a lenticular shape. In the area with weak water production and not too large well spacing density (less than 4 wells per square kilometer), the drainage radius can be approximately equal to the effective sand body radius without considering the influence of gas well water production on the drainage radius, and thus the ratio of the effective sand body radius of each layer is approximately equal to the ratio of the drainage radius of each layer.

[0043] It can be understood that the equal relationship between the ratio of the effective sand body radius and the ratio of the drainage radius is equivalent to the equal relationship between the arithmetic square root of the effective sand body area and the ratio of the drainage radius. Therefore, the electronic device can select any one of the multiple layers of the target gas well as the reference layer, and can default to set the first layer from top to bottom as the reference layer for the convenience of management of multiple gas wells. The electronic device can randomly determine the drainage radius of the reference layer in the pre-set drainage radius reference range. The drainage radius reference range can be determined based on the experience of researchers.

[0044] According to the effective sand body area of each layer section and the drainage radius of the preset reference layer section, the electronic device can calculate the drainage radius of other layer sections except the reference layer section according to the proportional relationship between the effective sand body area and the drainage radius, so as to obtain the drainage radius of each layer section of the target gas well. After obtaining the drainage radius of each layer section, the electronic device can calculate the dynamic reserves of each layer section based on the volumetric method formula.

[0045] In S140, the bottom hole flowing pressure of each layer section is determined according to the wellhead oil pressure data obtained in advance.

[0046] The electronic device can obtain the wellhead oil pressure data of each layer section of the target gas well in advance through the gas well management platform. The wellhead oil pressure data of each layer section can include the wellhead oil pressure of the layer section on each production day. According to the wellhead oil pressure data, the electronic device can calculate the bottom hole flowing pressure of each layer section in turn.

[0047] Specifically, the electronic device can calculate the bottom hole flowing pressure of each layer section on each production day according to the wellhead oil pressure of each layer section on each production day, the measured daily gas production of each production day, the average temperature in the oil pipe, the average pressure in the oil pipe of each production day, the average viscosity of natural gas in the oil pipe of each production day obtained in advance, the pipe string parameters obtained in advance, and the middle depth of each layer section obtained in advance.

[0048] In S150, the daily gas production estimate value of each layer section is determined according to the drainage radius of each layer section, the dynamic reserves of each layer section, the pseudo-pressure function matched with the bottom hole flowing pressure of each layer section, and the formation pressure of each layer section on the initial day.

[0049] After obtaining the bottom hole flowing pressure of each layer section on each production day, the electronic device can calculate the daily gas production estimate value of each layer section according to the drainage radius of each layer section, the dynamic reserves of each layer section, the pseudo-pressure function matched with the bottom hole flowing pressure of each layer section, and the formation pressure of each layer section on the initial day based on the gas well productivity binomial model and the material balance model. The formation pressure of each layer section on the initial day can be obtained in advance.

[0050] The electronic device can obtain a pseudo-pressure function matched with the formation pressure of each layer on the initial day according to the formation pressure of each layer on the initial day. The electronic device can obtain the estimated daily gas production of each layer on the initial day by inputting the pseudo-pressure function matched with the formation pressure of each layer on the initial day, the drainage radius of each layer and the pseudo-pressure function matched with the bottom-hole flowing pressure of each layer into the gas well productivity binomial model. The electronic device can obtain the formation pressure of each layer on the second day by inputting the estimated daily gas production of each layer on the initial day, the formation pressure of each layer on the initial day and the dynamic reserves of each layer into the material balance model. The electronic device can determine a pseudo-pressure function matched with the formation pressure of each layer on the second day, and obtain the estimated daily gas production of each layer on the second day by inputting the pseudo-pressure function matched with the formation pressure of each layer on the second day, the drainage radius of each layer and the pseudo-pressure function matched with the bottom-hole flowing pressure of each layer into the gas well productivity binomial model. The electronic device can obtain the formation pressure of each layer on the third day by inputting the estimated daily gas production of each layer on the second day, the formation pressure of each layer on the second day and the dynamic reserves of each layer into the material balance model. In this way, the electronic device can obtain the estimated daily gas production of each layer by continuously using the gas well productivity binomial model and the material balance model to output data alternately.

[0051] S160, determining a gas production error according to the estimated daily gas production of each layer and the measured daily gas production of the target gas well.

[0052] The electronic device can accumulate the estimated daily gas production of each layer according to the number of production days to obtain the estimated cumulative gas production of each layer, and accumulate the estimated cumulative gas production of each layer according to the number of layers to obtain the estimated cumulative gas production of the target gas well. Meanwhile, the electronic device can accumulate the measured daily gas production of the target gas well according to the number of production days to obtain the measured cumulative gas production of the target gas well. The electronic device can determine a gas production error according to the estimated cumulative gas production of the target gas well and the measured cumulative gas production of the target gas well. The gas production error can be determined based on the difference between the estimated cumulative gas production and the measured cumulative gas production.

[0053] S170, if the gas production error meets the preset accuracy condition, determining a layered evaluation result of the target gas well according to the drainage radius of each layer, the dynamic reserves of each layer and the estimated daily gas production of each layer.

[0054] It is easy to understand that the electronic device can pre-set the accuracy condition for evaluating the gas production error. The accuracy condition can be a reasonable value range of the gas production error, for example, 0-0.01, or a gas production error threshold, for example, 0.01. The electronic device can compare the gas production error with the pre-set accuracy condition, and if the gas production error meets the pre-set accuracy condition, the drainage radius of each layer, the dynamic reserves of each layer, and the daily gas production estimation value of each layer are taken as the evaluation results of the target gas well.

[0055] The technical scheme of the embodiment of the present application obtains the effective sand thickness data associated with the target gas well, the pre-fitted thickness-length relationship of the effective sand, and the pre-fitted thickness-width relationship of the effective sand; determines the effective sand area of each layer of the target gas well according to the effective sand thickness data, the thickness-length relationship, and the thickness-width relationship; determines the drainage radius of the layers other than the reference layer according to the effective sand area of each layer and the pre-set drainage radius of the reference layer, and determines the dynamic reserves of each layer according to the drainage radius of each layer; determines the bottom hole flowing pressure of each layer according to the pre-obtained wellhead oil pressure data; determines the daily gas production estimation value of each layer according to the drainage radius of each layer, the dynamic reserves of each layer, the pre-pressure function matched with the bottom hole flowing pressure of each layer, and the initial daily formation pressure of each layer; determines the gas production error according to the daily gas production estimation value of each layer and the pre-obtained measured value of the daily gas production of the target gas well; and if the gas production error meets the pre-set accuracy condition, determines the evaluation results of the target gas well according to the drainage radius of each layer, the dynamic reserves of each layer, and the daily gas production estimation value of each layer. The technical scheme solves the problem of low accuracy of the productivity layer-by-layer evaluation of the multi-layer commingled gas well, realizes the layer-by-layer splitting of the gas well production, and improves the reliability of the evaluation factors such as the layer-by-layer gas production, the drainage radius, and the dynamic reserves.

[0056] Embodiment two

[0057] Figure 2 A flowchart of a method for productivity layer-by-layer evaluation of a multi-layer commingled gas well is provided for the second embodiment of the present application, which is refined based on the above-mentioned embodiments. As shown in Figure 2 , the method comprises:

[0058] S201, obtaining the effective sand thickness data associated with the target gas well, the pre-fitted thickness-length relationship of the effective sand, and the pre-fitted thickness-width relationship of the effective sand.

[0059] In the present scheme, the thickness-width relationship and the thickness-length relationship of the effective sand can be determined by the exponential relationship Y=ah bwherein Y represents the length or width of the effective sand body, a and b represent the exponential term coefficient and the exponential coefficient respectively, and h represents the thickness of the effective sand body. It should be noted that the exponential term coefficient and the exponential coefficient of the thickness-length relationship and the thickness-width relationship can be the same or different, and in general, they should be different. In a specific example, the thickness-length relationship is represented as L = 576.37h 0.2282 , and the thickness-width relationship is represented as W = 315.08h 0.2775 , wherein L represents the length of the effective sand body, and W represents the width of the effective sand body.

[0060] S202. According to the effective sand body thickness data, the thickness-length relationship, and the thickness-width relationship, the effective sand body area of each interval of the target gas well is determined.

[0061] It can be understood that the calculation formula of the effective sand body area can be represented as A k = W k L k ; wherein k represents the interval identifier, W k represents the effective sand body width of the interval k, L k represents the effective sand body length of the interval k, and A k represents the effective sand body area of the interval k.

[0062] S203. The ratio of the effective sand body area of each interval to the effective sand body area of the first interval is determined.

[0063] There is a proportional relationship between the effective sand body area and the drainage radius: wherein r k represents the drainage radius of the interval k, r0 represents the drainage radius of the reference interval, A k represents the effective sand body area of the interval k, and A0 represents the effective sand body area of the reference interval.

[0064] Based on the proportional relationship between the effective sand body area and the drainage radius, the electronic device can first calculate the ratio of the effective sand body area of each interval to the effective sand body area of the first interval.

[0065] S204. According to the ratio of the effective sand body area of each interval to the effective sand body area of the first interval, and the pre-set drainage radius of the first interval, the drainage radius of the intervals other than the reference interval is determined.

[0066] In this scheme, the reference interval is the first interval, and r0 can be the pre-set drainage radius of the first interval. According to the ratio of the effective sand body area of each interval to the effective sand body area of the first interval obtained by S203, and the drainage radius of the first interval, the electronic device can calculate the drainage radius of the intervals other than the reference interval, thereby obtaining the drainage radius of each interval.

[0067] S205, determine the dynamic reserves of each layer section according to the drainage radius of each layer section, the effective sand thickness of each layer section, the wellbore radius obtained in advance, the porosity of each layer section, the gas saturation of each layer section, and the gas volume factor of each layer section.

[0068] Specifically, the calculation formula of the dynamic reserves can be represented as:

[0069] Gk=πr2hφkSgkBkZk k Gk represents the dynamic reserves of the layer section k, r represents the wellbore radius, h represents the effective sand thickness of the layer section k, φ represents the porosity of the layer section k, S represents the original gas saturation of the layer section k, B represents the gas volume factor corresponding to the original formation pressure of the layer section k, and Z represents the gas compressibility factor. w k k gik gik

[0070] S206, determine the bottom-hole flowing pressure of each layer section according to the wellhead oil pressure data obtained in advance.

[0071] In the scheme, optionally, the bottom-hole flowing pressure of each layer section is determined according to the wellhead oil pressure data obtained in advance, including:

[0072] The bottom-hole flowing pressure of each layer section is calculated according to the wellhead oil pressure data of each layer section obtained in advance, the daily gas production measured value of each layer section obtained in advance, the average temperature in the oil pipe determined in advance, the average pressure in the oil pipe determined in advance, the average viscosity of natural gas in the oil pipe obtained in advance, the pipe string parameter obtained in advance, and the middle depth of each layer section obtained in advance.

[0073] On the basis of the above scheme, optionally, the pipe string parameter includes the roughness of the inner wall of the oil pipe and the inner diameter of the oil pipe.

[0074] The bottom-hole flowing pressure of each layer section is calculated according to the wellhead oil pressure data of each layer section obtained in advance, the daily gas production measured value of each layer section obtained in advance, the average temperature in the oil pipe determined in advance, the average pressure in the oil pipe determined in advance, the average viscosity of natural gas in the oil pipe obtained in advance, the pipe string parameter obtained in advance, and the middle depth of each layer section obtained in advance.

[0075] The Reynolds number of the fluid flowing in the oil pipe is calculated according to the daily gas production measured value of each layer section, the inner diameter of the oil pipe, the relative density of natural gas obtained in advance, and the average viscosity of natural gas in the oil pipe.

[0076] The wall friction coefficient of the oil pipe is calculated according to the Reynolds number, the roughness of the inner wall of the oil pipe, and the inner diameter of the oil pipe.

[0077] ​​​​​determining an average deviation factor of the natural gas in the tubing based on the average pressure in the tubing, the average temperature in the tubing, the average relative density of the natural gas, the tubing wall friction coefficient, the tubing diameter, the average temperature in the tubing, and the average deviation factor of the natural gas in the tubing;

[0078] calculating the bottom hole flowing pressure of each layer based on the wellhead oil pressure data of each layer, the daily gas production measured value of each layer, the average relative density of the natural gas, the middle depth of each layer, the tubing wall friction coefficient, the tubing diameter, the average temperature in the tubing, and the average deviation factor of the natural gas in the tubing.

[0079] In this embodiment, the average temperature in the tubing is the average of the bottom hole temperature and the wellhead temperature of the target gas well; the average pressure in the tubing includes the average pressure in the tubing of at least two days, and in the case that the current day is not the initial day, the average pressure in the tubing of the current day is determined based on the wellhead oil pressure data of the current day and the bottom hole flowing pressure of the target gas well on the previous day.

[0080] Specifically, the bottom hole flowing pressure calculation formula of the initial day of the target gas well production can be expressed as:

[0081] P wj1 =(1+7.523×10 -5 H k )P t1 ; wherein P wj1 represents the bottom hole flowing pressure of the initial day of the target gas well production, H k represents the middle depth of layer k, and P t1 represents the wellhead oil pressure of the initial day of the target gas well production.

[0082] The bottom hole flowing pressure calculation formula of other days except the initial day of the target gas well production can be expressed as:

[0083]

[0084] wherein j represents the target gas well production day index, P wjk represents the bottom hole flowing pressure of layer k on the jth day of the target gas well production, P tj represents the wellhead oil pressure on the jth day of the target gas well production, represents the average temperature in the tubing, represents the average deviation factor of the natural gas in the tubing on the jth day of the target gas well production, q mj represents the daily gas production measured value on the jth day of the target gas well production, f j represents the tubing wall friction coefficient on the jth day of the target gas well production, d represents the tubing diameter, and C j represents the intermediate coefficient.

[0085] In the bottom hole flowing pressure calculation formula, wherein T w represents the bottom hole temperature of the target gas well, T t represents the wellhead temperature of the target gas well, and Hk r represents the depth at the middle of segment k. g Re represents the relative density of natural gas. j This represents the Reynolds number of the fluid flow inside the tubing on day j of the target gas well's production. This represents the average viscosity of natural gas in the tubing on day j after the target gas well begins production.

[0086] It can be determined based on the average pressure in the tubing on the j-th day after the target gas well is put into production and the mapping relationship between the average pressure and the average deviation factor of natural gas. The formula for calculating the average pressure in the tubing can be expressed as: in, P represents the average pressure in the tubing on day j after the target gas well begins production. w(j-1) This represents the bottom hole flowing pressure on day j-1 of the target gas well's production.

[0087] S207. Based on the discharge radius of each layer, the gas phase permeability of each layer, the effective sand body thickness of each layer, the formation temperature of each layer, and the wellbore radius, determine the first coefficient of the gas well productivity binomial model.

[0088] It's easy to understand that the binomial expression for the gas well production capacity per production day can be represented as:

[0089]

[0090] Where, q jk t represents the estimated daily gas production of section k on day j of the target gas well's production. j ψ represents the well start-up time on the j-th day after the target gas well begins production. jk The pseudo-pressure function representing the pressure matching of formation k is denoted by a. k b represents the first coefficient of segment k. jk The second coefficient of the k-th layer on the j-th day after the target gas well is put into production.

[0091] The electronic equipment can calculate the first matching coefficient for each layer based on the discharge radius, gas phase permeability, effective sand body thickness, formation temperature, and wellbore radius of each layer.

[0092] Specifically, the formula for calculating the first coefficient can be expressed as: Among them, T k K represents the formation temperature of section k. gk h represents the gas phase permeability of segment k. k The effective sand body thickness of segment k is represented by S, and the wellbore contamination skin coefficient is represented by S.

[0093] S208. Calculate the inertial turbulence skin coefficient for each layer based on the gas phase permeability, natural gas viscosity, wellbore radius, and relative density of natural gas for each layer.

[0094] In this scheme, the formula for calculating the inertial turbulence skin coefficient for each production day can be expressed as: Among them, D jk u represents the inertial turbulence skin coefficient of layer k on day j of the target gas well's production. jk K represents the viscosity of natural gas in formation k on day j of the target gas well's production. gk r represents the gas phase permeability of segment k. g h represents the relative density of natural gas k r represents the effective sand body thickness of layer k. w Represents the wellbore radius.

[0095] S209. Based on the inertial turbulence skin coefficient of each layer, the gas phase permeability of each layer, the effective sand body thickness of each layer, and the formation temperature of each layer, determine the second coefficient of the gas well productivity binomial model.

[0096] Based on the inertial turbulence skin coefficient, gas permeability, effective sand body thickness, and formation temperature of each layer, the electronic equipment can calculate the matching second coefficient for each layer. Specifically, the formula for calculating the second coefficient can be expressed as: T k K represents the formation temperature of section k. gk h represents the gas phase permeability of segment k. k This indicates the effective sand body thickness of layer k.

[0097] S210. Based on the first coefficient, the second coefficient, the well opening time of the target gas well, the pseudo-pressure function matching the bottom-hole flowing pressure of each section, and the pseudo-pressure function matching the formation pressure of each section, determine the binomial model of gas well production capacity.

[0098] After obtaining the bottomhole flowing pressure of each segment output by S206, the electronic equipment can determine the pseudo-pressure function corresponding to the bottomhole flowing pressure of each segment. Specifically, the pseudo-pressure function matching the bottomhole flowing pressure of each segment can be expressed as: Where, ψ wjk P represents the pseudo-pressure function representing the bottomhole flowing pressure matching of section k on the j-th day after the target gas well is put into production. wjk The bottomhole flowing pressure of section k on day j of the target gas well's production is represented by u, the viscosity of natural gas is represented by Z, the deviation factor of natural gas is represented by P, and the pressure is represented by P.

[0099] Substituting the first coefficient obtained from S207, the second coefficient obtained from S209, the well opening time of the target gas well, the pseudo-pressure function matching the bottom-hole flowing pressure of each section, and the pseudo-pressure function matching the formation pressure of each section into the gas well productivity binomial equation, we obtain the gas well productivity binomial model. It should be noted that the first coefficient, the second coefficient, the well opening time of the target gas well, and the pseudo-pressure function matching the bottom-hole flowing pressure of each section are known quantities, while the pseudo-pressure function matching the formation pressure of each section is an unknown quantity.

[0100] S211. Based on the gas well production binomial model and the formation pressure of each layer on the initial day, calculate the estimated daily gas production of each layer on the initial day.

[0101] Understandably, the pseudo-pressure function corresponding to the formation pressure of each layer on each production day can be expressed as: Where, ψ jk P represents the pseudo-pressure function representing the formation pressure matching of segment k on day j of the target gas well's production. jk Let represent the formation pressure of segment k on day j of the target gas well's production, u represent the natural gas viscosity, Z represent the natural gas deviation factor, and P represent the pressure.

[0102] By substituting the formation pressure of each segment on the initial day into the pseudo-pressure function expression corresponding to the formation pressure of each segment on each production day, the electronic equipment can obtain the pseudo-pressure function matching the formation pressure of each segment on the initial day. Substituting the pseudo-pressure function matching the formation pressure of each segment on the initial day as a known quantity into the gas well production binomial model obtained in S210, the electronic equipment can calculate the estimated daily gas production of each segment on the initial day, i.e., q. 1k .

[0103] S212. Based on the estimated daily gas production of each layer on the initial day, and using the material balance model and the gas well production binomial model, calculate the estimated daily gas production of each layer on each production day after the initial day.

[0104] The mass balance model can be expressed as: Where, N jk This represents the cumulative gas production of section k on day j after the target gas well is put into production. G k Z represents the dynamic reserves of segment k. jk Z represents the natural gas deviation factor of formation k on day j of the target gas well's production. (j+1)k P represents the natural gas deviation factor of section k on day j+1 of the target gas well's production. jk P represents the formation pressure in section k on day j of the target gas well's production. (j+1)k This represents the formation pressure of segment k on day j+1 after the target gas well is put into production.

[0105] After obtaining the estimated daily gas production of each layer on the initial day, the electronic equipment can use a material balance model to obtain the formation pressure of each layer on the second day. Then, based on the pseudo-pressure function expression corresponding to the formation pressure of each layer on each production day, it obtains the pseudo-pressure function matching the formation pressure of each layer on the second day. Substituting the pseudo-pressure function matching the formation pressure of each layer on the second day into the gas well productivity binomial model obtained in S210, the electronic equipment can calculate the estimated daily gas production of each layer on the second day, i.e., q. 2k Similarly, electronic equipment can obtain the estimated daily gas production of each layer on each production day based on the material balance model and the binomial model of gas well production capacity.

[0106] S213. Determine the gas production error based on the estimated daily gas production of each layer and the pre-obtained measured daily gas production of the target gas well.

[0107] After obtaining the estimated daily gas production for each layer, the electronic equipment can sum the estimated daily gas production for each layer on each production day to obtain the estimated daily gas production for the target gas well. Specifically, the formula for calculating the estimated daily gas production for the target gas well can be expressed as: Where, q j This represents the estimated daily gas production on day j of the target gas well's commissioning, where n represents the number of formations, and q represents the daily gas production. jk This represents the estimated daily gas production of section k on day j of the target gas well's production.

[0108] The electronic equipment can calculate the estimated cumulative gas production of the target gas well based on the estimated daily gas production. The formula for calculating the cumulative gas production of the target gas well is as follows: Where, q j N represents the estimated daily gas production on day j after the target gas well is put into production, where J represents the cumulative number of days, and N represents the cumulative number of days. J This represents the estimated cumulative gas production over J days. Based on the measured daily gas production of the target gas well, electronic equipment can calculate the measured cumulative gas production of the target gas well. By comparing the estimated cumulative gas production of the target gas well with the measured cumulative gas production, the gas production error of the target gas well within the cumulative time period can be obtained. The formula for calculating the gas production error can be expressed as: Where, N m δ represents the measured cumulative gas production of the target gas well over J days, and δ represents the error in the cumulative gas production of the target gas well over J days.

[0109] S214. Determine whether the gas production error meets the preset accuracy condition.

[0110] The electronic device can compare the gas production error with the preset accuracy condition. If the gas production error meets the preset accuracy condition, then S215 is executed; if the gas production error does not meet the preset accuracy condition, then S216 is executed.

[0111] S215. Based on the discharge radius of each layer, the dynamic reserves of each layer, and the estimated daily gas production of each layer, determine the stratified evaluation results of the target gas well.

[0112] If the gas production error meets the preset accuracy conditions, it means that the estimated daily gas production of each layer is reasonable. The electronic equipment can generate the stratified evaluation results of the target gas well based on the discharge radius of each layer, the dynamic reserves of each layer, and the estimated daily gas production of each layer.

[0113] S216. Adjust the discharge radius of the first layer.

[0114] If the gas production error does not meet the preset accuracy condition, it indicates that the estimated daily gas production value of each section has a large estimation error. The electronic equipment can further determine the adjustment result of the discharge radius of the first section based on the gas production error, for example, by increasing or decreasing the value based on the discharge radius of the first section set in S204. The adjusted discharge radius of the first section is used as the new preset discharge radius, and the process returns to execute S204-S214 until the gas production error meets the preset accuracy condition, at which point the stratification evaluation result of the target gas well is output.

[0115] The technical solution of this invention involves acquiring effective sand body thickness data associated with the target gas well, a pre-fitted thickness-length relationship of the effective sand body, and a pre-fitted thickness-width relationship of the effective sand body; determining the effective sand body area of ​​each segment of the target gas well based on the effective sand body thickness data, the thickness-length relationship, and the thickness-width relationship; determining the drainage radius of other segments besides the reference segment based on the effective sand body area of ​​each segment and the drainage radius of a pre-set reference segment; and determining the dynamic reserves of each segment based on the drainage radius of each segment. The pre-acquired wellhead oil pressure data is used to determine the bottomhole flowing pressure of each section. Based on the drainage radius of each section, the dynamic reserves of each section, the pseudo-pressure function matching the bottomhole flowing pressure of each section, and the formation pressure of each section on the initial day, the estimated daily gas production of each section is determined. Based on the estimated daily gas production of each section and the pre-acquired measured daily gas production of the target gas well, the gas production error is determined. If the gas production error meets the preset accuracy conditions, the stratified evaluation result of the target gas well is determined based on the drainage radius of each section, the dynamic reserves of each section, and the estimated daily gas production of each section. This technical solution solves the problem of low accuracy in the stratified evaluation of production capacity of multi-layered syndicated gas wells, realizes stratified division of gas well production, and improves the reliability of evaluation factors such as stratified gas production, drainage radius, and dynamic reserves.

[0116] Example 3

[0117] Figure 3This is a schematic diagram of a multi-layered gas well production capacity stratification evaluation device provided in Embodiment 3 of the present invention. Figure 3 As shown, the device includes:

[0118] Data acquisition module 310 is used to acquire effective sand body thickness data associated with the target gas well, pre-fitted thickness-length relationship of effective sand body, and pre-fitted thickness-width relationship of effective sand body;

[0119] The sand body area determination module 320 is used to determine the effective sand body area of ​​each segment of the target gas well based on the effective sand body thickness data, the thickness-length relationship, and the thickness-width relationship.

[0120] The radius and reserve determination module 330 is used to determine the discharge radius of other layers besides the reference layer based on the effective sand body area of ​​each layer and the discharge radius of the pre-set reference layer, and to determine the dynamic reserve of each layer based on the discharge radius of each layer.

[0121] The bottom hole pressure determination module 340 is used to determine the bottom hole pressure of each section based on the pre-acquired wellhead oil pressure data.

[0122] The daily gas production estimation module 350 is used to determine the estimated daily gas production of each layer based on the discharge radius of each layer, the dynamic reserves of each layer, the pseudo-pressure function of the bottom hole flowing pressure matching of each layer, and the formation pressure of each layer on the initial day.

[0123] The gas production error determination module 360 ​​is used to determine the gas production error based on the estimated daily gas production of each layer and the pre-acquired measured daily gas production of the target gas well.

[0124] The first evaluation result determination module 370 is used to determine the stratified evaluation result of the target gas well based on the discharge radius of each stratum, the dynamic reserves of each stratum, and the estimated daily gas production of each stratum if the gas production error meets the preset accuracy conditions.

[0125] Optionally, in this solution, the device further includes:

[0126] The first evaluation result determination module 370 is used to, after determining the gas production error, if the gas production error does not meet the preset accuracy conditions, adjust the discharge radius of the reference layer, return to execute the determination of the discharge radius of other layers besides the reference layer based on the effective sand body area of ​​each layer and the pre-set discharge radius of the reference layer, until the gas production error meets the preset accuracy conditions, and output the stratification evaluation result of the target gas well.

[0127] Based on the above scheme, optionally, the reference segment is the first segment from top to bottom among all segments;

[0128] The radius and reserve determination module 330 is specifically used for:

[0129] Determine the ratio of the effective sand body area of ​​each layer to the effective sand body area of ​​the first layer;

[0130] Based on the ratio of the effective sand body area of ​​each layer to the effective sand body area of ​​the first layer, and the pre-set discharge radius of the first layer, the discharge radius of other layers besides the reference layer is determined.

[0131] The dynamic reserves of each layer are determined based on the discharge radius of each layer, the effective sand body thickness of each layer, the pre-obtained wellbore radius, the porosity of each layer, the gas saturation of each layer, and the natural gas volume coefficient of each layer.

[0132] In one feasible embodiment, the bottom hole flowing pressure determination module 340 is specifically used for:

[0133] Based on the pre-acquired wellhead oil pressure data of each section, the pre-acquired measured daily gas production of each section, the pre-determined average temperature inside the tubing, the pre-determined average pressure inside the tubing, the pre-acquired average viscosity of natural gas inside the tubing, the pre-acquired tubing string parameters, and the pre-acquired mid-depth of each section, the bottom hole flowing pressure of each section is calculated.

[0134] Based on the above scheme, optionally, the tubing string parameters include the inner wall roughness of the tubing and the inner diameter of the tubing;

[0135] The bottom hole flowing pressure determination module 340 is specifically used for:

[0136] The Reynolds number of the fluid flow in the oil pipe is calculated based on the measured daily gas production of each layer, the inner diameter of the oil pipe, the pre-obtained relative density of natural gas, and the average viscosity of natural gas in the oil pipe.

[0137] The friction coefficient of the inner wall of the oil pipe is calculated based on the Reynolds number, the roughness of the inner wall of the oil pipe, and the inner diameter of the oil pipe.

[0138] Determine the average deviation factor of natural gas in the tubing for matching the average pressure in the tubing.

[0139] Based on the wellhead oil pressure data of each section, the measured daily gas production of each section, the relative density of the natural gas, the mid-depth of each section, the friction coefficient of the tubing inner wall, the inner diameter of the tubing, the average temperature inside the tubing, and the average deviation factor, the bottom hole flowing pressure of each section is calculated.

[0140] Optionally, the average temperature inside the tubing is the average of the bottom hole temperature and the wellhead temperature of the target gas well;

[0141] The average pressure inside the tubing includes the average pressure inside the tubing for at least two days. If the current day is not the initial day, the average pressure inside the tubing for the current day is determined based on the wellhead oil pressure data for the current day and the bottom hole flowing pressure of the target gas well on the previous day.

[0142] In a preferred embodiment, the daily gas production estimation module 350 is specifically used for:

[0143] The first coefficient of the gas well productivity binomial model is determined based on the discharge radius of each layer, the gas phase permeability of each layer, the effective sand body thickness of each layer, the formation temperature of each layer, and the wellbore radius.

[0144] The inertial turbulence skin coefficient of each layer is calculated based on the gas phase permeability, natural gas viscosity of each layer, wellbore radius, and natural gas relative density.

[0145] The second coefficient of the gas well productivity binomial model is determined based on the inertial turbulence skin coefficient, gas phase permeability, effective sand body thickness, and formation temperature of each layer.

[0146] Based on the first coefficient, the second coefficient, the well opening time of the target gas well, the pseudo-pressure function matching the bottom-hole flowing pressure of each section, and the pseudo-pressure function matching the formation pressure of each section, the binomial model of gas well production capacity is determined.

[0147] Based on the aforementioned binomial model of gas well production capacity and the formation pressure of each section on the initial day, the estimated daily gas production of each section on the initial day is calculated.

[0148] Based on the estimated daily gas production of each layer on the initial day, and using the material balance model and the gas well production binomial model, the estimated daily gas production of each layer on each production day after the initial day is calculated.

[0149] The multi-layer gas well production capacity stratification evaluation device provided in this embodiment of the invention can execute the multi-layer gas well production capacity stratification evaluation method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0150] Example 4

[0151] Figure 4A schematic diagram of an electronic device 410 that can be used to implement embodiments of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0152] like Figure 4 As shown, the electronic device 410 includes at least one processor 411 and a memory, such as a read-only memory (ROM) 412 or a random access memory (RAM) 413, communicatively connected to the at least one processor 411. The memory stores computer programs executable by the at least one processor. The processor 411 can perform various appropriate actions and processes based on the computer program stored in the ROM 412 or loaded from storage unit 418 into the RAM 413. The RAM 413 may also store various programs and data required for the operation of the electronic device 410. The processor 411, ROM 412, and RAM 413 are interconnected via a bus 414. An input / output (I / O) interface 415 is also connected to the bus 414.

[0153] Multiple components in electronic device 410 are connected to I / O interface 415, including: input unit 416, such as keyboard, mouse, etc.; output unit 417, such as various types of displays, speakers, etc.; storage unit 418, such as disk, optical disk, etc.; and communication unit 419, such as network card, modem, wireless transceiver, etc. Communication unit 419 allows electronic device 410 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0154] Processor 411 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 411 include, but are not limited to, central processing unit (CPU), graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, digital signal processors (DSPs), and any suitable processor, controller, microcontroller, etc. Processor 411 performs the various methods and processes described above, such as the production capacity stratification evaluation method for multi-layered gas wells.

[0155] In some embodiments, the method for evaluating the production capacity stratification of multi-layered gas wells can be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 418. In some embodiments, part or all of the computer program can be loaded and / or installed on electronic device 410 via ROM 412 and / or communication unit 419. When the computer program is loaded into RAM 413 and executed by processor 411, one or more steps of the method for evaluating the production capacity stratification of multi-layered gas wells described above can be performed. Alternatively, in other embodiments, processor 411 can be configured to perform the method for evaluating the production capacity stratification of multi-layered gas wells by any other suitable means (e.g., by means of firmware).

[0156] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), system-on-a-chip (SoCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transferring data and instructions to the storage system, the at least one input device, and the at least one output device.

[0157] Computer programs used to implement the methods of this invention can be written in any combination of one or more programming languages. These computer programs can be provided to the processor of a general-purpose computer, a special-purpose computer, or other programmable multi-layered gas well production stratification evaluation device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The computer programs can be executed entirely on a machine, partially on a machine, as a standalone software package partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0158] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0159] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0160] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0161] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0162] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0163] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for evaluating the production capacity of multi-layered syndicated gas wells, characterized in that, The method includes: Acquire the effective sand body thickness data associated with the target gas well, the pre-fitted thickness-length relationship of the effective sand body, and the pre-fitted thickness-width relationship of the effective sand body; Based on the effective sand body thickness data, the thickness-length relationship, and the thickness-width relationship, determine the effective sand body area of ​​each section of the target gas well; Based on the effective sand body area of ​​each layer and the pre-set discharge radius of the reference layer, the discharge radius of other layers besides the reference layer is determined, and the dynamic reserves of each layer are determined based on the discharge radius of each layer. Based on the pre-acquired wellhead oil pressure data, determine the bottom hole flowing pressure of each section; Based on the discharge radius of each layer, the dynamic reserves of each layer, the pseudo-pressure function for bottom hole pressure matching of each layer, and the formation pressure of each layer on the initial day, the estimated daily gas production of each layer is determined. Based on the estimated daily gas production of each layer and the pre-obtained measured daily gas production of the target gas well, the gas production error is determined. If the gas production error meets the preset accuracy conditions, the stratified evaluation result of the target gas well is determined based on the discharge radius of each stratum, the dynamic reserves of each stratum, and the estimated daily gas production of each stratum.

2. The method according to claim 1, characterized in that, After determining the gas production error, the method further includes: If the gas production error does not meet the preset accuracy condition, the discharge radius of the reference section is adjusted, and the process returns to determine the discharge radius of other sections besides the reference section based on the effective sand body area of ​​each section and the pre-set discharge radius of the reference section, until the gas production error meets the preset accuracy condition, and the stratification evaluation result of the target gas well is output.

3. The method according to claim 2, characterized in that, The reference segment is the first segment from top to bottom in each segment; The step of determining the discharge radius of other layers besides the reference layer based on the effective sand body area of ​​each layer and the discharge radius of the pre-set reference layer includes: Determine the ratio of the effective sand body area of ​​each layer to the effective sand body area of ​​the first layer; Based on the ratio of the effective sand body area of ​​each layer to the effective sand body area of ​​the first layer, and the pre-set discharge radius of the first layer, the discharge radius of other layers besides the reference layer is determined. The determination of the dynamic reserves of each layer based on the discharge radius of each layer includes: The dynamic reserves of each layer are determined based on the discharge radius of each layer, the effective sand body thickness of each layer, the pre-obtained wellbore radius, the porosity of each layer, the gas saturation of each layer, and the natural gas volume coefficient of each layer.

4. The method according to claim 3, characterized in that, The step of determining the bottom hole flowing pressure of each section based on pre-acquired wellhead oil pressure data includes: Based on the pre-acquired wellhead oil pressure data of each section, the pre-acquired measured daily gas production of each section, the pre-determined average temperature inside the tubing, the pre-determined average pressure inside the tubing, the pre-acquired average viscosity of natural gas inside the tubing, the pre-acquired tubing string parameters, and the pre-acquired mid-depth of each section, the bottom hole flowing pressure of each section is calculated.

5. The method according to claim 4, characterized in that, The tubing string parameters include the inner wall roughness of the tubing and the inner diameter of the tubing. The calculation of bottom hole flowing pressure for each section, based on pre-acquired wellhead oil pressure data, pre-acquired measured daily gas production values ​​for each section, pre-determined average tubing temperature, pre-determined average tubing pressure, pre-acquired average natural gas viscosity in the tubing, pre-acquired tubing string parameters, and pre-determined mid-depth of each section, includes: The Reynolds number of the fluid flow in the oil pipe is calculated based on the measured daily gas production of each layer, the inner diameter of the oil pipe, the pre-obtained relative density of natural gas, and the average viscosity of natural gas in the oil pipe. The friction coefficient of the inner wall of the oil pipe is calculated based on the Reynolds number, the roughness of the inner wall of the oil pipe, and the inner diameter of the oil pipe. Determine the average deviation factor of natural gas in the tubing for matching the average pressure in the tubing. Based on the wellhead oil pressure data of each section, the measured daily gas production of each section, the relative density of the natural gas, the mid-depth of each section, the friction coefficient of the tubing inner wall, the inner diameter of the tubing, the average temperature inside the tubing, and the average deviation factor, the bottom hole flowing pressure of each section is calculated.

6. The method according to claim 5, characterized in that, The average temperature inside the tubing is the average of the bottom hole temperature and the wellhead temperature of the target gas well. The average pressure inside the tubing includes the average pressure inside the tubing for at least two days. If the current day is not the initial day, the average pressure inside the tubing for the current day is determined based on the wellhead oil pressure data for the current day and the bottom hole flowing pressure of the target gas well on the previous day.

7. The method according to claim 3, characterized in that, The method of determining the estimated daily gas production of each layer based on the discharge radius of each layer, the dynamic reserves of each layer, the pseudo-pressure function for bottom hole flowing pressure matching of each layer, and the formation pressure of each layer on the initial day includes: The first coefficient of the gas well productivity binomial model is determined based on the discharge radius of each layer, the gas phase permeability of each layer, the effective sand body thickness of each layer, the formation temperature of each layer, and the wellbore radius. The inertial turbulence skin coefficient of each layer is calculated based on the gas phase permeability, natural gas viscosity of each layer, wellbore radius, and natural gas relative density. The second coefficient of the gas well productivity binomial model is determined based on the inertial turbulence skin coefficient, gas phase permeability, effective sand body thickness, and formation temperature of each layer. Based on the first coefficient, the second coefficient, the well opening time of the target gas well, the pseudo-pressure function matching the bottom-hole flowing pressure of each section, and the pseudo-pressure function matching the formation pressure of each section, the binomial model of gas well production capacity is determined. Based on the aforementioned binomial model of gas well production capacity and the formation pressure of each section on the initial day, the estimated daily gas production of each section on the initial day is calculated. Based on the estimated daily gas production of each layer on the initial day, and using the material balance model and the gas well production binomial model, the estimated daily gas production of each layer on each production day after the initial day is calculated.

8. A production capacity stratification evaluation device for multi-layered syngas wells, characterized in that, The device includes: The data acquisition module is used to acquire the effective sand body thickness data associated with the target gas well, the pre-fitted thickness-length relationship of the effective sand body, and the pre-fitted thickness-width relationship of the effective sand body. The sand body area determination module is used to determine the effective sand body area of ​​each segment of the target gas well based on the effective sand body thickness data, the thickness-length relationship, and the thickness-width relationship. The radius and reserve determination module is used to determine the discharge radius of other layers besides the reference layer based on the effective sand body area of ​​each layer and the discharge radius of the pre-set reference layer, and to determine the dynamic reserve of each layer based on the discharge radius of each layer. The bottom hole flowing pressure determination module is used to determine the bottom hole flowing pressure of each section based on the pre-acquired wellhead oil pressure data; The daily gas production estimation module is used to determine the estimated daily gas production of each layer based on the discharge radius of each layer, the dynamic reserves of each layer, the pseudo-pressure function for bottom hole pressure matching of each layer, and the formation pressure of each layer on the initial day. The gas production error determination module is used to determine the gas production error based on the estimated daily gas production of each layer and the pre-acquired measured daily gas production of the target gas well. The first evaluation result determination module is used to determine the stratified evaluation result of the target gas well based on the discharge radius of each stratum, the dynamic reserves of each stratum, and the estimated daily gas production of each stratum if the gas production error meets the preset accuracy conditions.

9. An electronic device, characterized in that, The electronic device includes: At least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the production capacity stratification evaluation method for multi-layered gas wells according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that cause a processor to execute the production capacity stratification evaluation method for multi-layered gas wells as described in any one of claims 1-7.

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