Method for determining sealing performance of injection-production tubular column of injection-production gas well and related equipment

Abstract

The invention discloses a method for determining the sealing performance of an injection-production pipe column of an injection-production gas well and related equipment, and relates to the technical field of oil and gas exploitation, and the method comprises the steps that the depth of a leakage point of the injection-production pipe column is determined according to a target annular pressure value of a target injection-production gas well at a preset time node; according to the annulus state parameters of the target injection-production gas well, the annulus protection liquid compression volume and the annulus upper gas column compression volume are determined; according to the annulus protection liquid compression volume, the annulus upper gas column compression volume and the injection-production pipe column leakage point depth, the leakage point equivalent aperture is determined; and according to the leakage point depth and the leakage point equivalent aperture, the tubular column sealing degree of the target injection-production gas well is determined. The leakage point depth and the equivalent aperture are calculated through the annular pressure data and the dynamic change rule, then the sealing performance of the injection-production pipe column of the injection-production gas well is accurately evaluated, complex downhole operation is not needed, and the detection convenience, the calculation accuracy and the treatment efficiency are improved.

Description

Technical Field

[0001] The present application relates to the technical field of oil and gas production, and more specifically, to a method for determining the sealing performance of an injection and production pipe string in an injection and production gas well and related equipment. Background Art

[0002] With the continuous development of oil and gas field exploitation technology, injection and production wells play an important role in application fields such as gas production, gas injection and gas storage; however, the long-term use of injection and production strings and complex working conditions may lead to leakage problems, thereby causing the A annulus pressure phenomenon, affecting wellbore safety and production efficiency. Especially in conventional gas production wells, CCUS gas injection wells and gas storage injection and production wells, the A annulus pressure problem has become a technical problem that needs to be solved urgently.

[0003] In the related art, the detection of leakage points in injection and production wells mostly relies on traditional downhole testing methods or test equipment. This method is not only costly and inefficient, but may also limit the accuracy of data due to the complex downhole environment. At the same time, in the existing technology, leakage point detection usually focuses on simple leakage depth analysis, and fails to conduct in-depth research in combination with the dynamic change law of the annular pressure of the injection and production string. This limitation makes it difficult for traditional methods to accurately predict the location of leakage points and their equivalent apertures, which limits the accurate evaluation of the sealing performance of the injection and production string of the injection and production gas well, and thus affects the design and implementation of the treatment plan for the A annular pressure problem. That is, there are technical problems in the related art for the determination of the sealing performance of the injection and production string of the injection and production gas well, such as insufficient accuracy, complex process, and low efficiency. Summary of the invention

[0004] A series of simplified concepts are introduced in the summary of the invention, which will be further described in detail in the detailed description. The summary of the invention of this application does not mean to attempt to define the key features and essential technical features of the technical solution claimed for protection, nor does it mean to attempt to determine the scope of protection of the technical solution claimed for protection.

[0005] The method for determining the sealing performance of the injection and production tubing of an injection and production gas well and the related devices provided in the present application can calculate the depth of the leakage point and the equivalent pore size through the annular space pressure data and the dynamic change law, and then accurately evaluate the sealing performance of the injection and production tubing of the injection and production gas well, without the need for complicated downhole operations, thereby improving the convenience of detection, calculation accuracy and control efficiency.

[0006] In a first aspect, the present application provides a method for determining the sealing performance of an injection and production tubing of an injection and production gas well, comprising: determining the depth of a leakage point of the injection and production tubing according to a target annulus pressure value of a target injection and production gas well at a preset time node; determining the compression volume of annulus protection liquid and the compression volume of an upper gas column in the annulus according to annulus state parameters of the target injection and production gas well; determining the equivalent pore size of the leakage point according to the compression volume of annulus protection liquid, the compression volume of the upper gas column in the annulus and the depth of the leakage point of the injection and production tubing; determining the sealing degree of the tubing of the target injection and production gas well according to the depth of the leakage point and the equivalent pore size of the leakage point.

[0007] In a feasible implementation, determining the depth of the leakage point of the injection and production tubing string based on the target annulus pressure value of the target injection and production gas well at a preset time node includes: determining the final value of annulus pressure recovery based on the target annulus pressure value; determining the depth of the leakage point of the injection and production tubing string based on the final value of annulus pressure recovery.

[0008] In a feasible implementation, determining the final value of annular pressure recovery according to the target annular pressure value includes: determining the annular pressure recovery change rate at the preset time node according to the target annular pressure value; performing function fitting according to the annular pressure recovery change rate to obtain a change rate fitting function; and determining the final value of the annular pressure recovery when the annular pressure recovery change rate is 0 based on the change rate fitting function.

[0009] In a feasible implementation manner, determining the depth of the leakage point of the injection and production string according to the final value of the annular space pressure recovery includes: substituting the final value of the annular space pressure recovery into a preset depth calculation function to obtain the depth of the leakage point of the injection and production string, wherein the preset depth calculation function is:

[0010]

[0011] In the formula, h tg is the depth of the leakage point of the injection and production string, P head is the wellhead pressure of the target gas injection and production well, P end is the final value of the annular pressure recovery, L g is the length of the gas column at the top of the annulus of the target gas injection and production well, g is the gravitational acceleration, ρ l is the annular protection fluid density of the target gas injection and production well, ρ g is the injection and production gas density of the target injection and production gas well.

[0012] In a feasible embodiment, the annulus state parameters include annulus protection liquid compression coefficient, annulus protection liquid volume, first annulus air column pressure, second annulus air column pressure and first annulus air column volume, wherein the first annulus air column pressure is the annulus air column pressure at the first preset time node, the second annulus air column pressure is the annulus air column pressure at the second preset time node, and the first annulus air column volume is the annulus air column volume at the first preset time node; the annulus protection liquid compression volume and the annulus protection liquid compression volume are determined according to the annulus state parameters of the target injection and production gas well. The compressed volume of the upper gas column in the annulus comprises: calculating the product of the annulus protection liquid compression coefficient, the annulus protection liquid volume and the air column pressure difference to obtain the compressed volume of the annulus protection liquid, wherein the air column pressure difference is the difference between the second annulus air column pressure and the first annulus air column pressure; obtaining the compressed volume of the upper gas column in the annulus according to the product of the first annulus air column volume and the pressure ratio complement, wherein the pressure ratio complement is the complement of the air column pressure ratio with respect to 1, and the air column pressure ratio is the ratio of the second annulus air column pressure to the first annulus air column pressure.

[0013] In a feasible implementation manner, the equivalent pore size of the leakage point is determined according to the compressed volume of the annulus protection liquid, the compressed volume of the upper gas column of the annulus and the depth of the leakage point of the injection and production string, including: determining the leakage gas volume at the second preset time node according to the compressed volume of the annulus protection liquid, the compressed volume of the upper gas column of the annulus and the depth of the leakage point of the injection and production string; substituting the leakage gas volume into the small hole model to calculate the equivalent pore size of the leakage point.

[0014] In a feasible implementation manner, the determining of the leakage gas volume at the second preset time node according to the compressed volume of the annular protection liquid, the compressed volume of the gas column above the annular space and the depth of the leakage point of the injection and production string comprises: substituting the compressed volume of the annular protection liquid, the compressed volume of the gas column above the annular space and the depth of the leakage point of the injection and production string into a preset volume calculation function to obtain the leakage gas volume, wherein the preset volume calculation function is:

[0015]

[0016] Where V tg is the gas volume leaked from the leakage point at the second preset time node, P g ' is the air column pressure of the second ring, g is the acceleration due to gravity, M l is the mass of the annular protection fluid of the target gas injection and production well, P tube is the pressure inside the injection and production pipe at the leakage point of the target injection and production well, V l is the volume of the annular protection liquid, V gis the volume of the first ring air column, h tg is the depth of the leakage point of the injection and production string, S A is the annular cross-sectional area of ​​the target gas injection and production well, DV l is the compressed volume of the annular protection fluid, DV g is the compressed volume of the gas column above the annulus.

[0017] In the second aspect, the present application also provides a device for determining the sealing performance of an injection and production tubing of an injection and production gas well, comprising: a depth determination unit, used to determine the depth of the leakage point of the injection and production tubing according to the target annulus pressure value of the target injection and production gas well at a preset time node; a volume determination unit, used to determine the compression volume of the annulus protection liquid and the compression volume of the upper gas column in the annulus according to the annulus state parameters of the target injection and production gas well; an aperture determination unit, used to determine the equivalent aperture of the leakage point according to the compression volume of the annulus protection liquid, the compression volume of the upper gas column in the annulus and the depth of the leakage point of the injection and production tubing; a sealing determination unit, used to determine the degree of sealing of the tubing of the target injection and production gas well according to the depth of the leakage point and the equivalent aperture of the leakage point.

[0018] In a third aspect, the present application further provides an electronic device, comprising: a memory and a processor, wherein the processor is used to implement the steps of the method for determining the sealing performance of the injection and production tubing of an injection and production gas well as described in the first aspect when executing the computer program stored in the memory.

[0019] In a fourth aspect, the present application further provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the method for determining the sealing performance of an injection and production tubing string of an injection and production gas well as described in the first aspect.

[0020] In a fifth aspect, the present application also provides a computer program product, including a computer program or computer executable instructions. When the computer program or computer executable instructions are executed by a processor, the method for determining the sealing performance of the injection and production tubing of an injection and production gas well provided in an embodiment of the present application is implemented.

[0021] In summary, the present application uses the annulus pressure value of the target injection and production gas well at a preset time node and the dynamic pressure change law to accurately calculate the depth of the leakage point of the injection and production string, thereby achieving positioning only through ground data analysis without relying on complex downhole detection instruments or test equipment, thereby improving the convenience of detection; according to the annulus state parameters, the compressed volume of the annulus protection fluid and the compressed volume of the upper gas column in the annulus are calculated respectively, and the fluid characteristics and pressure change law in the annulus are fully considered, thereby improving the accuracy of the volume parameter calculation, and laying a solid foundation for the subsequent calculation of the equivalent aperture of the leakage point; the detection of key parameters is completed through pressure data and calculation models, thus avoiding the complex process of traditional downhole operations and greatly reducing the workload of operations; accurate leakage point positioning and rapid determination of the equivalent aperture can realize accurate judgment of the sealing of the string, which is efficient and economical, and can greatly improve the efficiency of the treatment of the annulus pressure problem of the injection and production well A. To summarize, the method for determining the sealing performance of the injection and production tubing of a gas injection and production well provided in the present application calculates the depth of the leakage point and the equivalent pore size through the annular space pressure data and the dynamic change law, and then accurately evaluates the sealing performance of the injection and production tubing of the gas injection and production well, without the need for complicated downhole operations, thereby improving detection convenience, calculation accuracy and management efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present specification. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0023] Figure 1 A flow chart of a method for determining the sealing performance of an injection and production string of an injection and production gas well provided in an embodiment of the present application;

[0024] Figure 2 A schematic diagram of the composition structure of a device for determining the sealing performance of an injection and production pipe string in an injection and production gas well provided in an embodiment of the present application;

[0025] Figure 3 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0026] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "is" and "has" and any variations thereof involved in the present application are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0027] The term "module" or "unit" in this application refers to a computer program or a part of a computer program that has a predetermined function and works together with other related parts to achieve a predetermined goal, and can be implemented in whole or in part by using software, hardware (such as processing circuits or memories) or a combination thereof. Similarly, a processor (or multiple processors or memories) can be used to implement one or more modules or units. In addition, each module or unit can be part of an overall module or unit that includes the function of the module or unit.

[0028] It should be noted that the wellbore structure of conventional gas production wells, CCUS gas injection wells and gas storage injection and production wells includes surface casing, technical casing and oil layer casing from outside to inside; the space between the injection and production tubing and the oil layer casing is the A annulus, and outwards are the B, C, and D annuli (some injection and production gas wells may not have C and D annuli); the injection and production tubing usually adopts an airtight tubing (applicable to gas production wells and gas storage injection and production wells) or a continuous oil pipe (applicable to CCUS gas injection wells), and is equipped with auxiliary tools such as downhole packers. The A annulus is usually filled with protective fluid (in the gas storage injection and production well, a certain amount of nitrogen may be reserved in the upper part of the A annulus), and its pressure can be monitored and recorded in real time by a pressure gauge at the wellhead. Unless otherwise specified, the expressions involving "annulus" in the following text of this application are all abbreviations of "A annulus".

[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. In the following description, it is related to "some embodiments", which describes a subset of all possible embodiments, but it can be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict.

[0030] See also Figure 1 , Figure 11 is a flow chart of a method for determining the sealing performance of an injection and production pipe string of an injection and production gas well provided in an embodiment of the present application. The method may specifically include the following steps 101 to 104:

[0031] Step 101, determining the depth of the leakage point of the injection and production string according to the target annular pressure value of the target injection and production gas well at a preset time node;

[0032] Specifically, the target injection and production gas well is the specific injection and production well (such as a conventional gas production well, a CCUS injection well, or a gas storage injection and production well) that is currently being tested or analyzed. The preset time node is a specific moment divided according to the time series when analyzing the annular pressure change, which is used to record and calculate the pressure recovery data; each preset time node corresponds to a pressure value, and the time node interval (such as every second, every minute) can be reasonably set according to the pressure recovery after the annular discharge and the corresponding time data to ensure data accuracy. The target annular pressure value is the actual pressure value of the annulus A of the target injection and production gas well at each preset time node. The annular pressure value can be collected by a pressure sensor. The depth of the injection and production tubing leakage point is the depth position of the injection and production tubing leakage point of the target injection and production gas well in the wellbore, that is, the vertical distance from the wellhead to the leakage point. The leakage point depth is calculated by analyzing the final value of the annular pressure recovery.

[0033] By implementing step 101, the dynamic change pattern of the annular space pressure at a specific time point is analyzed, and the depth position of the leakage point can be accurately calculated; by using the ground pressure data, there is no need to rely on complex downhole detection equipment, thus avoiding the high cost and cumbersome process of traditional downhole detection methods.

[0034] Step 102, determining the annular protection liquid compression volume and the annular upper gas column compression volume according to the annular state parameters of the target gas injection and production well;

[0035] Specifically, the annulus state parameters are multiple parameters used to describe the physical state of the annulus of the target injection and production gas well. They can be obtained by field measurements or laboratory tests and are used to calculate the compression behavior of the annulus protection fluid and the gas column. The annulus protection fluid compression volume refers to the compression of the protection fluid volume caused by the annulus pressure change. The annulus protection fluid compression volume reflects the compressibility change of the protection fluid under different pressure conditions and can be used to analyze the pressure transmission effect of the annulus. The annulus upper gas column compression volume refers to the compression of the gas column volume caused by the annulus pressure change. The gas column volume compression is based on the compressibility characteristics of the gas and is nonlinearly related to the pressure change.

[0036] By implementing step 102, the compressed volumes of the annular protection fluid and the gas column are calculated, and the mechanical properties and compression behavior of the fluid in the annular space are fully captured to ensure the scientific nature and integrity of the parameters, thus providing reliable input data for the subsequent equivalent pore size analysis of the leakage point.

[0037] Step 103, determining the equivalent aperture of the leakage point according to the compressed volume of the annular space protection liquid, the compressed volume of the gas column above the annular space and the depth of the leakage point of the injection and production string;

[0038] Specifically, the equivalent pore size of the leakage point refers to the equivalent pore size of the leakage point of the injection and production string, which characterizes the leakage capacity of the leakage point. It is usually assumed that the leakage point is a regular small circular hole. It can be used to quantify the size of the leakage point and the gas leakage rate. It is a key parameter for assessing the severity of leakage and designing control measures. The equivalent pore size of the leakage point can be calculated based on the small hole model through parameters such as the leakage gas volume, pressure difference and gas physics.

[0039] Through the implementation of step 103, based on the depth and volume parameters of the leakage point, combined with fluid mechanics and the small hole model, the equivalent pore size of the leakage point can be scientifically calculated, which helps to quickly evaluate the scale and nature of the leakage based on the accurately obtained equivalent pore size.

[0040] Step 104, determining the sealing degree of the pipe string of the target gas injection and production well according to the depth of the leakage point and the equivalent pore size of the leakage point;

[0041] Specifically, the sealing degree of the tubing string is an indicator that quantitatively describes the sealing integrity of the injection and production tubing string of the target gas injection and production well at the leakage point. Through the calculation results of the leakage point depth and equivalent aperture, it can be determined whether the tubing string has a sealing defect at this location and the severity of the defect; the sealing degree can be evaluated by comparing the actual measured leakage point depth, equivalent aperture and design sealing requirements (such as maximum depth, maximum allowable leakage), and combined with downhole pressure, temperature and other working parameters for comprehensive analysis; if the leakage point equivalent aperture exceeds the design allowable value, it can be determined that the seal has failed; the tubing string sealing degree can be expressed in specific grades or percentages.

[0042] For example, first, the depth of the leakage point of the target gas injection and production well can be compared with the maximum leakage depth allowed in the design; if the actual leakage point depth is less than the maximum depth required by the design, it is considered that the sealing performance in terms of depth is good; if the actual leakage point depth exceeds the maximum design depth, it is considered that the sealing performance is poor; the quantitative value of the influence of the leakage point depth on the sealing degree (the ratio of the actual leakage point depth to the maximum design leakage point depth) can account for a part of the evaluation result (for example, 30%). Then, the actual equivalent aperture of the leakage point is compared with the maximum equivalent aperture allowed in the design; the smaller the actual equivalent aperture, the smaller the leakage point and the better the sealing performance; and if the actual equivalent aperture exceeds the maximum design value, it means that there is a larger leakage aperture and the sealing performance is poor; the quantitative value of the influence of the aperture (the complement of the ratio of the actual leakage point equivalent aperture to the maximum design equivalent aperture about 1) also accounts for a part of the evaluation (for example, 70%). Finally, by weighted average, the evaluation results of the leakage point depth and the equivalent aperture are synthesized into an overall sealing degree percentage.

[0043] For example, the target gas injection and production well has a leakage point depth of 2500 meters, an equivalent hole of 4 mm, a maximum allowable leakage depth of 3000 meters, and a maximum allowable equivalent aperture of 5 mm. The quantitative value of the influence of the leakage point depth on the sealing degree accounts for 30% of the evaluation result, and the quantitative value of the influence of the equivalent aperture accounts for 70% of the evaluation result. Then, the sealing degree of the tubing string can be calculated as follows: (2500 / 3000)×30%+(1-4 / 5)×70%=39.00%. If the design standard sealing degree is 50%, the sealing performance of the target gas injection and production well does not meet the design standard. For another example, the leakage point depth of the target gas injection and production well is 2100 meters, the equivalent hole of the leakage point is 1mm, the maximum allowable leakage depth is 3000 meters, and the maximum allowable equivalent aperture is 5mm. The quantitative value of the influence of the leakage point depth on the sealing degree accounts for 20% of the evaluation result, and the quantitative value of the influence of the equivalent aperture accounts for 80% of the evaluation; then, the sealing degree of the tubing string can be calculated = (2100 / 3000) × 20% + (1-1 / 5) × 80% = 78.00%. If the design standard sealing degree is 50%, the sealing performance of the target gas injection and production well meets the design standard.

[0044] Through the implementation of step 104, it is possible to quickly and accurately determine whether the pipe string seal meets the design standard based on the leakage point depth and equivalent pore diameter, and quantify the degree of its sealing failure, thereby providing a scientific basis for wellbore integrity management and providing data support for subsequent repair or control measures.

[0045] In summary, the embodiment of the present application uses the annulus pressure value of the target injection and production gas well at a preset time node and the dynamic pressure change law to accurately calculate the depth of the leakage point of the injection and production string, so that there is no need to rely on complex downhole detection instruments or test equipment, and positioning can be achieved only through ground data analysis, thereby improving the convenience of detection; according to the annulus state parameters, the compressed volume of the annulus protection fluid and the compressed volume of the upper gas column in the annulus are calculated respectively, and the fluid characteristics and pressure change law in the annulus are fully considered, thereby improving the accuracy of volume parameter calculation, and laying a solid foundation for the subsequent calculation of the equivalent aperture of the leakage point; the detection of key parameters is completed through pressure data and calculation models, which avoids the complex process of traditional downhole operations and greatly reduces the workload of operations; accurate leakage point positioning and rapid determination of the equivalent aperture can realize accurate judgment of the sealing of the tubing string, which is efficient and economical, and can greatly improve the efficiency of controlling the annulus pressure problem of the injection and production well A. In summary, the method for determining the sealing performance of the injection and production tubing of the injection and production gas well provided in the embodiment of the present application calculates the leakage point depth and equivalent pore size through the annulus pressure data and dynamic change law, and then accurately evaluates the sealing performance of the injection and production tubing of the injection and production gas well, without the need for complicated downhole operations, thereby improving detection convenience, calculation accuracy and management efficiency.

[0046] In some embodiments, the aforementioned step 101 may include: determining a final value of annular pressure recovery according to a target annular pressure value; and determining a depth of a leakage point of the injection-production string according to the final value of annular pressure recovery.

[0047] Specifically, the final value of annulus pressure recovery is determined by fitting the annulus pressure change curve to determine the final pressure value when the pressure recovers to a stable state, which is used to reflect the steady-state characteristics of the annulus system; the depth of the leakage point of the injection-production tubing is the leakage point position calculated based on the final value of pressure recovery, combined with the structural parameters and fluid characteristics of the injection-production well, which indicates the vertical distance of the leakage point from the wellhead.

[0048] For example, after the annular pressure of a gas storage well was released, the pressure value recorded at the preset time node gradually recovered; by fitting the pressure change curve, the final value of the annular pressure recovery was calculated; further combined with the wellhead pressure, gas column length and protective fluid density, it was determined that the leakage point was located at a depth of about 1,500 meters. Through this process, not only can the pressure recovery state be accurately captured, but the specific depth of the leakage point can also be effectively located, providing accurate data basis for subsequent treatment.

[0049] Through the implementation of the above embodiment, the final value of pressure recovery is calculated to capture the real state of leakage of the injection and production string, and the final value of pressure recovery is used to reflect the depth position of the leakage point, thereby avoiding the depth deviation in the traditional detection method.

[0050] In some embodiments, determining the final value of annular pressure recovery based on the target annular pressure value may include: determining the annular pressure recovery change rate at a preset time node based on the target annular pressure value; performing function fitting based on the annular pressure recovery change rate to obtain a change rate fitting function; and determining the final value of the annular pressure recovery when the annular pressure recovery change rate is 0 based on the change rate fitting function.

[0051] Specifically, the annular pressure recovery change rate represents the rate of pressure change at each preset time node, which is calculated from the pressure values ​​at adjacent preset time nodes; the change rate fitting function is an expression obtained by mathematically fitting the change rate data of multiple preset time nodes, which is used to predict the pressure change trend; the annular pressure recovery final value is the pressure value when the change rate is zero calculated by the change rate fitting function, which represents the final value of the pressure recovery to a stable state. The calculation formula for the annular pressure recovery change rate is as follows.

[0052]

[0053] In the formula, vp t is the recovery change rate of annulus A pressure at the t-th preset time node, P t+1 is the pressure value of annulus A at the preset time node t+1, P tis the A annulus pressure value at the t-th preset time node, Δt is the difference between the time values ​​at the t+1-th preset time node and the t-th preset time node, and t is an integer greater than or equal to 1.

[0054] For example, in the operation of a gas storage well, after the annular pressure is released, the pressure gauge records the annular pressure value every 5 minutes; by calculation, the pressure recovery change rate between every two adjacent preset time nodes is obtained, and these data are fitted into a change rate curve in the form of a linear function; when the change rate curve extends to 0, the corresponding pressure value is determined as the final value of the annular pressure recovery, indicating that the pressure has reached a balanced state. This final value is then used to infer the depth of the injection and production string leakage point.

[0055] Through the implementation of the above embodiment, the fitting function is used to accurately determine the final value of pressure recovery when the change rate is 0, thereby improving the depth calculation accuracy, being able to cope with pressure fluctuations under complex working conditions, and ensuring stable data results.

[0056] In some embodiments, the aforementioned determination of the depth of the leakage point of the injection and production string according to the final value of the annular space pressure recovery may include: substituting the final value of the annular space pressure recovery into a preset depth calculation function to obtain the depth of the leakage point of the injection and production string, wherein the preset depth calculation function is:

[0057]

[0058] In the formula, h tg is the depth of the leakage point of the injection and production string, P head is the wellhead pressure of the target gas injection and production well, P end is the final value of annular pressure recovery, L g is the length of the gas column at the top of the annulus of the target gas injection and production well, g is the gravitational acceleration, ρ l is the annular protection fluid density of the target gas injection and production well, ρ g is the injection and production gas density of the target injection and production gas well.

[0059] Specifically, the final value of annulus pressure recovery is a stable pressure value determined by collecting annulus pressure data of target injection and production gas wells and using a fitting method, which reflects the final equilibrium state in the annulus. The calculation of the depth of the leakage point of the injection and production string requires the combination of known parameters such as wellhead pressure, length of the gas column at the top of the annulus, density of the protective fluid, and density of the injection and production gas. The specific location of the leakage point is obtained by substituting the final value of the annulus pressure recovery into the depth calculation formula. This process fully considers the density difference between the annular gas column and the protective fluid and its impact on the pressure distribution.

[0060] For example, in a gas storage injection well, the wellhead pressure is 10 MPa, the annular pressure recovery final value is calculated to be 9 MPa, the length of the annular top gas column is 100 meters, and the density of the protective fluid is 1100 kg / m 3The density of injected gas is 1.2kg / m 3 , the acceleration due to gravity is 9.8 m / s 2 ; After substituting these parameters into the depth calculation formula, the depth of the leakage point is calculated to be 194 meters.

[0061] Through the implementation of the above-mentioned embodiments, a depth calculation model is established using physical parameters (annulus pressure, gas column length, protective fluid density, etc.), which comprehensively considers key parameters such as wellhead pressure, annulus top gas column length, protective fluid density and gas density to ensure the theoretical basis of the calculation results and adapt to the complex working conditions of different injection and production wells.

[0062] In some embodiments, the aforementioned annulus state parameters may include annulus protection liquid compression coefficient, annulus protection liquid volume, first annulus air column pressure, second annulus air column pressure and first annulus air column volume, wherein the aforementioned first annulus air column pressure is the annulus air column pressure at a first preset time node, the second annulus air column pressure is the annulus air column pressure at a second preset time node, and the first annulus air column volume is the annulus air column volume at the first preset time node; step 102 may include: calculating the product of the annulus protection liquid compression coefficient, the annulus protection liquid volume and the air column pressure difference to obtain the annulus protection liquid compression volume, wherein the air column pressure difference is the difference between the second annulus air column pressure and the first annulus air column pressure; according to the product of the first annulus air column volume and the pressure ratio complement, obtaining the annulus upper air column compression volume, wherein the pressure ratio complement is the complement of the air column pressure ratio with respect to 1, and the air column pressure ratio is the ratio of the second annulus air column pressure to the first annulus air column pressure.

[0063] Specifically, the annular protection fluid compressibility coefficient is a function that describes the compression characteristics of the annular protection fluid under pressure (unit: MPa). -1 ), that is, the unit volume compression caused by unit pressure change, which reflects the compressibility of the protection fluid when the pressure changes. The annular protection fluid volume is the total initial volume of the protection fluid filled in the annular space (unit: m 3 ), the volume of protective fluid is usually the value set during the construction design of the injection and production well, which is related to the well depth and the cross-sectional area of ​​the annulus, and is recorded in the design parameters of the injection and production well. The first-ring air column pressure is the actual pressure (unit: MPa) of the gas column at the top of the annulus at the first preset time node (that is, the initial moment), which can be obtained by real-time measurement of the pressure gauge at the wellhead, and is used as the initial value for subsequent pressure change rate and gas column compression volume calculation. The second-ring air column pressure is the actual pressure (unit: MPa) of the gas column at the top of the annulus at the second preset time node, which indicates the state of the pressure in the annulus after changing with time. The difference between the pressure of the first-ring air column and the pressure of the first-ring air column reflects the degree of pressure change. The volume of the first-ring air column is the total initial volume of the gas column at the top of the annulus at the first preset time node (unit: m 3), represents the initial state of the gas column and is used to calculate the compressed volume of the gas column; the volume of the first ring gas column can be calculated based on the length and cross-sectional area of ​​the gas column at the top of the annulus, which is part of the construction parameters of the injection and production well.

[0064] The compressed volume of the annular protection fluid can be calculated by the following formula (3), and the compressed volume of the gas column above the annular space can be calculated by the following formula (4):

[0065] DV l =C l V l (P g ′-P g ) (3)

[0066]

[0067] Where DV l is the compressed volume of the annular protection fluid, C l is the annulus protection fluid compressibility coefficient, V l is the volume of the annular protection fluid, P g is the air column pressure of the first ring, P g ' is the air column pressure of the second ring, DV g is the compressed volume of the gas column above the annulus, V g is the volume of the air column in the first ring.

[0068] For example, in the analysis of a certain injection and production well, the pressure of the first ring air column is 8MPa, the pressure of the second ring air column is 9MPa, and the volume of the first ring air column is 10m 3 , the compression coefficient of the annular protection liquid is 0.0001MPa -1 , the volume of annular protection liquid is 20m 3 ; Through calculation, the compressed volume of the annular protection fluid is 0.002m 3 The compressed volume of the gas column above the annulus is 1.11m 3 .

[0069] Through the implementation of the above embodiment, the compression effects of liquid and gas are comprehensively considered, the dynamic characteristics of the medium in the annulus are fully reflected, and the accuracy of key parameters is improved by step-by-step calculation of the protective liquid and gas column volumes, providing reliable data for subsequent calculations.

[0070] In some embodiments, the aforementioned step 103 may include: determining the leakage gas volume at a second preset time node based on the compression volume of the annulus protection liquid, the compression volume of the upper gas column in the annulus, and the depth of the leakage point of the injection and production string; substituting the leakage gas volume into the small hole model to calculate the equivalent pore size of the leakage point.

[0071] Specifically, the leakage gas volume refers to the amount of gas that leaks into the annulus through the leakage point at the second preset time node, which is calculated in combination with the compressed volume of the annulus protection fluid and the compressed volume of the gas column to reflect the gas leakage characteristics of the leakage point; by utilizing the depth of the leakage point of the injection and production string and the fluid parameters of the injection and production well (such as protection fluid density, gas density, wellhead pressure, etc.), the pressure conditions and flow changes near the leakage point can be quantitatively described; the equivalent aperture of the leakage point can be calculated through the small hole model: assuming that the leakage point is a regular small circular hole, the equivalent aperture size of the leakage point is comprehensively obtained according to the leakage gas volume, the pressure difference at the leakage point and the gas density, so as to accurately evaluate its leakage capacity. The specific calculation of the small hole model can be referred to the relevant paper materials, such as the relevant research results of Wang Zhaoqin in "Research on Leakage Model of High-Pressure Gas Pipeline and Analysis of Consequence Impact Area".

[0072] For example, in the analysis of a gas injection well, the annular protection fluid compression volume is calculated to be 0.3m 3 The compressed volume of the gas column above the annulus is calculated to be 1.2m 3 The depth of the injection and production pipe leakage point is 600 meters; the wellhead pressure is 10MPa, the pressure in the pipe at the leakage point is 8MPa, and the gas density is 1.2kg / m 3 ; Through calculation, the volume of gas leakage at the second preset time node is 0.00002m 3 After substituting this volume into the small hole model, it can be calculated that the equivalent pore diameter of the leakage point is 0.0005 m (0.5 mm).

[0073] Through the implementation of the above embodiments, the pore model is combined with the volume of leaking gas to comprehensively characterize the pore size characteristics of the leakage point, and the pore size measurement results can intuitively reflect the leakage scale of the leakage point, providing a key basis for the design of the treatment plan.

[0074] In some embodiments, the aforementioned determination of the leakage gas volume at the second preset time node based on the annular space protection liquid compression volume, the annular space upper gas column compression volume and the injection and production string leakage point depth may include: substituting the annular space protection liquid compression volume, the annular space upper gas column compression volume and the injection and production string leakage point depth into the preset volume calculation function to obtain the leakage gas volume, wherein the preset volume calculation function is:

[0075]

[0076] Where V tg is the gas volume leaked from the leakage point at the second preset time node, P g ' is the air column pressure of the second ring, g is the acceleration due to gravity, M l is the quality of the annular protection fluid of the target gas injection and production well, P tube is the pressure inside the injection and production string at the leakage point of the target injection and production gas well, Vl is the volume of the annular protection fluid, V g is the volume of the first ring air column, h tg is the depth of the leakage point of the injection and production string, S A is the annular cross-sectional area of ​​the target gas injection and production well, DV l is the compressed volume of the annular protection fluid, DV g It is the compressed volume of the gas column above the annulus.

[0077] Specifically, the calculation process of the leakage gas volume comprehensively considers the compression effect of the annulus protection fluid and the compression effect of the gas column, as well as the influence of the depth of the leakage point of the injection and production string on the volume change; the calculation of the compressed volume of the annulus protection fluid and the compressed volume of the gas column are based on the dynamic characteristics of the pressure change and the physical parameters, respectively, and the introduction of the leakage point depth ensures the consistency between the volume calculation results and the actual downhole working conditions; by substituting the above parameters into the preset volume calculation formula, the leakage gas volume at the second preset time node is accurately obtained, which provides basic data for the subsequent analysis of the leakage scale and control measures of the leakage point.

[0078] Through the implementation of the above-mentioned embodiments, the volume calculation formula comprehensively considers various physical parameters (protective liquid volume, mass, gas column pressure, etc.), ensures the scientific nature of the leakage gas volume calculation results, and can reflect the leakage characteristics of different preset time nodes according to the dynamic changes of the annular space compression volume and the leakage point depth.

[0079] Furthermore, as an implementation of the aforementioned method embodiment, the present application also provides a device for determining the sealing performance of an injection and production tubing string in an injection and production gas well, which is used to implement the aforementioned method embodiment. The device embodiment corresponds to the aforementioned method embodiment. For ease of reading, the present device embodiment for determining the sealing performance of an injection and production tubing string in an injection and production gas well will no longer repeat the details of the aforementioned method embodiment one by one, but it should be clear that the device in the embodiment of the present application can correspond to and implement all the contents of the aforementioned method embodiment. Figure 2 As shown, the device 20 for determining the sealing performance of the injection and production tubing of the injection and production gas well includes: a depth determination unit 201, a volume determination unit 202, an aperture determination unit 203 and a sealing determination unit 204, wherein the depth determination unit 201 is used to determine the depth of the leakage point of the injection and production tubing according to the target annulus pressure value of the target injection and production gas well at a preset time node; the volume determination unit 202 is used to determine the compression volume of the annulus protection liquid and the compression volume of the upper gas column in the annulus according to the annulus state parameters of the target injection and production gas well; the aperture determination unit 203 is used to determine the equivalent aperture of the leakage point according to the compression volume of the annulus protection liquid, the compression volume of the upper gas column in the annulus and the depth of the leakage point of the injection and production tubing; the sealing determination unit 204 is used to determine the sealing degree of the tubing of the target injection and production gas well according to the leakage point depth and the equivalent aperture of the leakage point.

[0080] In some embodiments, the depth determination unit 201 is further used to determine the final value of annular pressure recovery according to the target annular pressure value; and to determine the depth of the leakage point of the injection and production string according to the final value of annular pressure recovery.

[0081] In some embodiments, the depth determination unit 201 is also used to determine the annular pressure recovery change rate at a preset time node based on the target annular pressure value; perform function fitting based on the annular pressure recovery change rate to obtain a change rate fitting function; and determine the annular pressure recovery final value when the annular pressure recovery change rate is 0 based on the change rate fitting function.

[0082] In some embodiments, the depth determination unit 201 is further used to substitute the final value of the annular pressure recovery into a preset depth calculation function to obtain the depth of the injection and production string leakage point, wherein the preset depth calculation function is the above formula (2), where h tg is the depth of the leakage point of the injection and production string, P head is the wellhead pressure of the target gas injection and production well, P end is the final value of annular pressure recovery, L g is the length of the gas column at the top of the annulus of the target gas injection and production well, g is the gravitational acceleration, ρ l is the annular protection fluid density of the target gas injection and production well, ρ g is the injection and production gas density of the target injection and production gas well.

[0083] In some embodiments, the annulus state parameters include annulus protection liquid compression coefficient, annulus protection liquid volume, first annulus air column pressure, second annulus air column pressure and first annulus air column volume, wherein the first annulus air column pressure is the annulus air column pressure at a first preset time node, the second annulus air column pressure is the annulus air column pressure at a second preset time node, and the first annulus air column volume is the annulus air column volume at the first preset time node; the volume determination unit 202 is also used to calculate the product of the annulus protection liquid compression coefficient, the annulus protection liquid volume and the air column pressure difference to obtain the annulus protection liquid compression volume, wherein the air column pressure difference is the difference between the second annulus air column pressure and the first annulus air column pressure; according to the product of the first annulus air column volume and the pressure ratio complement, the compression volume of the upper annulus air column is obtained, wherein the pressure ratio complement is the complement of the air column pressure ratio with respect to 1, and the air column pressure ratio is the ratio of the second annulus air column pressure to the first annulus air column pressure.

[0084] In some embodiments, the aperture determination unit 203 is also used to determine the volume of leakage gas at a second preset time node based on the compression volume of the annulus protection fluid, the compression volume of the gas column above the annulus, and the depth of the leakage point of the injection and production string; the leakage gas volume is substituted into the small hole model to calculate the equivalent aperture of the leakage point.

[0085] In some embodiments, the aperture determination unit 203 is further used to substitute the compressed volume of the annular protection liquid, the compressed volume of the gas column above the annular space, and the depth of the leakage point of the injection and production string into a preset volume calculation function to obtain the leakage gas volume, wherein the preset volume calculation function is the above formula (5), where V tg is the gas volume leaked from the leakage point at the second preset time node, P g ' is the air column pressure of the second ring, g is the acceleration due to gravity, M l is the quality of the annular protection fluid of the target gas injection and production well, P tube is the pressure inside the injection and production string at the leakage point of the target injection and production gas well, V l is the volume of the annular protection fluid, V g is the volume of the first ring air column, h tg is the depth of the leakage point of the injection and production string, S A is the annular cross-sectional area of ​​the target gas injection and production well, DV l is the compressed volume of the annular protection fluid, DV g It is the compressed volume of the gas column above the annulus.

[0086] The present application also provides a computer-readable storage medium, which stores computer-executable instructions or computer programs. When the computer-executable instructions or computer programs are executed by a processor, the processor will be caused to execute any step of the method for determining the sealing performance of the injection and production tubing of an injection and production gas well provided in the present application.

[0087] In some embodiments, the computer-readable storage medium may be a memory such as RAM, read-only memory (ROM), flash memory, magnetic surface memory, optical disk, or compact disc read-only memory (CD-ROM); or it may be various devices including one or any combination of the above memories.

[0088] In some embodiments, computer executable instructions may be in the form of a program, software, software module, script or code, written in any form of programming language (including compiled or interpreted languages, or declarative or procedural languages), and may be deployed in any form, including as a stand-alone program or as a module, component, subroutine or other unit suitable for use in a computing environment.

[0089] In some embodiments, computer-executable instructions may, but need not, correspond to a file in a file system, may be stored as part of a file storing other programs or data, for example, in one or more scripts in a HyperText Markup Language (HTML) document, in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files storing one or more modules, subroutines, or code portions).

[0090] In some embodiments, computer executable instructions may be deployed to be executed on one electronic device, or on multiple electronic devices located at one site, or on multiple electronic devices distributed at multiple sites and interconnected by a communication network.

[0091] like Figure 3 As shown, the present application also provides an electronic device 30, including a memory 310, a processor 320, and a computer program 311 stored in the memory 310 and executable on the processor. When the processor 320 executes the computer program 311, any step of the above-mentioned method for determining the sealing performance of the injection and production tubing of the injection and production gas well is implemented.

[0092] The present application also provides a computer program product, which includes a computer program or a computer executable instruction, and the computer program or the computer executable instruction is stored in a computer-readable storage medium. The processor of the electronic device reads the computer program or the computer executable instruction from the computer-readable storage medium, and the processor executes the computer program or the computer executable instruction, so that the electronic device executes any step of the method for determining the sealing performance of the injection and production pipe string of the injection and production gas well described in the present application.

[0093] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for determining the sealing performance of an injection and production pipe string in an injection and production gas well, characterized in that: include: Determine the depth of the leakage point of the injection and production string according to the target annular pressure value of the target injection and production gas well at the preset time node; Determine the annular protection fluid compression volume and the annular upper gas column compression volume according to the annular space state parameters of the target gas injection and production well; Determine the equivalent aperture of the leakage point according to the compressed volume of the annulus protection liquid, the compressed volume of the gas column above the annulus and the depth of the leakage point of the injection and production string; The sealing degree of the pipe string of the target gas injection and production well is determined according to the depth of the leakage point and the equivalent pore size of the leakage point.

2. The method according to claim 1, characterized in that Determining the depth of the leakage point of the injection and production string according to the target annular pressure value of the target injection and production gas well at a preset time node includes: Determining a final value of annular pressure recovery according to the target annular pressure value; The depth of the leakage point of the injection-production string is determined according to the final value of the annular space pressure recovery.

3. The method according to claim 2, characterized in that Determining the final value of annular pressure recovery according to the target annular pressure value includes: According to the target annular pressure value, determining the annular pressure recovery change rate at the preset time node; Perform function fitting according to the annular space pressure recovery change rate to obtain a change rate fitting function; Based on the change rate fitting function, the annular space pressure recovery final value when the annular space pressure recovery change rate is 0 is determined.

4. The method according to claim 2, characterized in that: Determining the depth of the leakage point of the injection and production string according to the final value of the annular space pressure recovery includes: Substitute the final value of the annular pressure recovery into the preset depth calculation function to obtain the depth of the leakage point of the injection and production string, wherein the preset depth calculation function is: In the formula, h tg is the depth of the leakage point of the injection and production string, P head is the wellhead pressure of the target gas injection and production well, P end is the final value of the annular pressure recovery, L g is the length of the gas column at the top of the annulus of the target gas injection and production well, g is the gravitational acceleration, ρ l is the annular protection fluid density of the target gas injection and production well, ρ g is the injection and production gas density of the target injection and production gas well.

5. The method according to claim 1, characterized in that The annulus state parameters include annulus protection liquid compressibility coefficient, annulus protection liquid volume, first annulus air column pressure, second annulus air column pressure and first annulus air column volume, wherein the first annulus air column pressure is the annulus air column pressure at the first preset time node, the second annulus air column pressure is the annulus air column pressure at the second preset time node, and the first annulus air column volume is the annulus air column volume at the first preset time node; The step of determining the compression volume of the annulus protection fluid and the compression volume of the gas column above the annulus according to the annulus state parameters of the target gas injection and production well comprises: Calculating the product of the annular space protection liquid compression coefficient, the annular space protection liquid volume and the air column pressure difference to obtain the annular space protection liquid compression volume, wherein the air column pressure difference is the difference between the second annular air column pressure and the first annular air column pressure; The compressed volume of the upper air column in the annulus is obtained according to the product of the volume of the first ring air column and the pressure ratio complement, wherein the pressure ratio complement is the complement of the air column pressure ratio with respect to 1, and the air column pressure ratio is the ratio of the pressure of the second ring air column to the pressure of the first ring air column.

6. The method according to claim 5, characterized in that Determining the equivalent aperture of the leakage point according to the compressed volume of the annulus protection liquid, the compressed volume of the gas column above the annulus and the depth of the leakage point of the injection and production string includes: Determine the volume of leaking gas at the second preset time node according to the compressed volume of the annular protection liquid, the compressed volume of the gas column above the annular space and the depth of the leakage point of the injection and production string; The leakage gas volume is substituted into the small hole model to calculate the equivalent pore diameter of the leakage point.

7. The method according to claim 6, characterized in that The step of determining the leakage gas volume at the second preset time node according to the compressed volume of the annular protection liquid, the compressed volume of the gas column above the annular space and the depth of the leakage point of the injection and production string comprises: Substitute the compressed volume of the annular protection liquid, the compressed volume of the upper gas column of the annular space and the depth of the leakage point of the injection and production string into the preset volume calculation function to obtain the leakage gas volume, wherein the preset volume calculation function is: Where V tg is the gas volume leaked from the leakage point at the second preset time node, P g ' is the air column pressure of the second ring, g is the acceleration due to gravity, M l is the mass of the annular protection fluid of the target gas injection and production well, P tube is the pressure inside the injection and production pipe at the leakage point of the target injection and production well, V l is the volume of the annular protection liquid, V g is the volume of the first ring air column, h tg is the depth of the leakage point of the injection and production string, S A is the annular cross-sectional area of ​​the target gas injection and production well, DV l is the compressed volume of the annular protection fluid, DV g is the compressed volume of the gas column above the annulus.

8. A device for determining the sealing performance of an injection and production pipe string of an injection and production gas well, characterized in that: include: A depth determination unit, used to determine the depth of the leakage point of the injection and production string according to the target annular pressure value of the target injection and production gas well at a preset time node; A volume determination unit, used to determine the compression volume of the annulus protection fluid and the compression volume of the gas column above the annulus according to the annulus state parameters of the target gas injection and production well; An aperture determination unit is used to determine the equivalent aperture of the leakage point according to the compressed volume of the annular space protection liquid, the compressed volume of the gas column above the annular space and the depth of the leakage point of the injection and production string; The sealing determination unit is used to determine the sealing degree of the pipe string of the target injection and production gas well according to the depth of the leakage point and the equivalent pore size of the leakage point.

9. An electronic device, comprising: A memory and a processor, wherein the processor is used to implement the steps of the method for determining the sealing performance of an injection and production tubing string in an injection and production gas well as described in any one of claims 1 to 7 when executing the computer program stored in the memory.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for determining the sealing performance of an injection and production string of an injection and production gas well as described in any one of claims 1 to 7 are implemented.

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