Method and system for evaluating gas lift process of water-producing gas well

Abstract

The invention discloses a method and system for evaluating the gas lift process of a water-producing gas well, and the method comprises the steps: obtaining a liquid discharge factor and a yield increase factor which represent the liquid discharge and yield increase characteristics of the gas lift process according to the production data of the water-producing gas well; according to the liquid drainage factor and the yield increase factor, a pre-constructed liquid drainage and yield increase relation model is utilized to obtain the working condition of the gas lift process of the current gas well; when the working condition is a first working condition type, obtaining an income index of each alternative operation scheme according to the operation data and the production data of each alternative operation scheme of the current gas lift process; and on the basis of the income index of each alternative operation scheme, the optimal gas production strategy of the gas lift process of the current water-producing gas well is optimized, so that the gas lift device of the current water-producing gas well operates according to the optimal gas production strategy. According to the method, the double effects of yield increasing and liquid discharging are accurately evaluated, the problem that the gas well effect evaluation index is single is solved, comparison and selection of different gas lift combination operation schemes are achieved, and the decision-making level of the gas well gas lift process is improved.

Description

Technical Field

[0001] This invention relates to the field of oil and gas extraction technology, and in particular to a method and system for evaluating gas lift processes in water-producing gas wells. Background Technology

[0002] In recent years, with the continuous expansion of the application of intelligent gas lift technology in water-producing gas wells, a series of intelligent gas lift devices and control systems have emerged. However, the current evaluation methods for intelligent gas lift technology mainly rely on changes in single indicators such as gas production, liquid production, and oil-casing pressure difference to evaluate the process effect.

[0003] However, existing evaluation methods face the following challenges: First, if the trends of different indicators are inconsistent, it is often difficult to determine the effectiveness, and there is no unified quantitative evaluation index; second, there is a lack of process effect evaluation methods that simultaneously consider drainage, production increase, and economic efficiency; finally, when the same well is used with different combined gas lift schemes, it is difficult to conduct quantitative evaluation and comparison, resulting in the determination of non-optimal gas lift process parameters. Summary of the Invention

[0004] The purpose of this invention is to provide an evaluation scheme for a gas lift process for water-producing gas wells that simultaneously considers both production enhancement and fluid drainage effects.

[0005] To address the aforementioned technical problems, this invention provides an evaluation method for evaluating gas lift processes in water-producing gas wells, comprising: obtaining a discharge factor and a production enhancement factor characterizing the discharge and production enhancement features of the gas lift process based on the production data of the water-producing gas well; obtaining the operating conditions of the current gas lift process of the gas well using a pre-constructed discharge-production relationship model based on the discharge factor and the production enhancement factor; when the operating conditions are of the first type, obtaining a benefit index for each alternative operating scheme based on the operating data of each alternative operating scheme of the current gas lift process and the production data; and, based on the benefit index of each alternative operating scheme, selecting the optimal gas production strategy for the current water-producing gas well gas lift process, so that the gas lift device of the current water-producing gas well operates according to the optimal gas production strategy.

[0006] Preferably, when the operating condition is the second type of operating condition, the gas lift process of the current water-producing gas well is replaced.

[0007] Preferably, the drainage-production enhancement relationship model includes a production enhancement effective zone, a drainage effective zone, and a process ineffective zone. The step of obtaining the operating condition of the gas lift process of the current gas well based on the drainage factor and the production enhancement factor using the pre-constructed drainage-production enhancement relationship model includes: when the drainage factor is less than or equal to a first threshold and the production enhancement factor is less than or equal to a second threshold, the operating condition is process ineffective; when the drainage factor is greater than the first threshold and the production enhancement factor is less than or equal to the second threshold, the operating condition is drainage effective; and when the drainage factor is greater than the first threshold and the production enhancement factor is greater than the second threshold, the operating condition is production enhancement effective.

[0008] Preferably, the effective production increase zone and the effective drainage zone both belong to the first type of operating condition; and the ineffective process zone belongs to the second type of operating condition.

[0009] Preferably, the revenue indicators include: unit gas consumption cost and total investment return rate. The step of selecting the optimal gas production strategy for the current water-producing gas well gas lift process based on the revenue indicators of each alternative operating scheme includes: when the unit gas consumption cost of an alternative operating scheme is less than a preset unit gas consumption cost threshold, and the total investment return rate is greater than a preset total investment return rate threshold, the current operating scheme is determined as the optimal gas production strategy. The preset unit gas consumption cost threshold is determined based on the minimum unit gas consumption cost of all alternative operating schemes, and the preset total investment return rate threshold is determined based on the maximum total investment return rate of all alternative operating schemes.

[0010] Preferably, the step of obtaining the drainage factor and production enhancement factor characterizing the drainage and production enhancement features of the gas lift process based on the production data of the water-producing gas well includes: using a gas-liquid two-phase flow model based on the production data of the water-producing gas well to obtain the annular pressure drop, tubing friction pressure drop, and tubing pressure drop, and further obtaining the real-time wellbore fluid accumulation; calculating the initial drainage volume of the gas well, and calculating the real-time drainage volume based on the real-time wellbore fluid accumulation, thereby obtaining the drainage factor based on the initial drainage volume and the real-time drainage volume; setting the daily production decline rate of the gas well, predicting the real-time daily gas production of the gas well, thereby obtaining the production enhancement factor based on the predicted and measured daily gas production values.

[0011] Preferably, the drainage factor is calculated using the following expression:

[0012]

[0013] Where, α i represents the drainage factor, q wi q represents the real-time drainage volume on day i of construction. w0 Q represents the initial drainage volume. j0Q represents the initial wellbore fluid volume. ji η represents the real-time wellbore fluid accumulation. i η0 represents the real-time drainage rate, and η0 represents the initial drainage rate.

[0014] Preferably, the yield-increasing factor is calculated using the following expression:

[0015] q yui =q g0 *(1-ε) i

[0016]

[0017] Where, λ i q represents the production increase factor. gi q represents the measured daily gas production on day i of construction. g0 ε represents the initial daily gas production, ε represents the preset daily production decline rate per well, i represents the number of days of construction, and q represents the initial daily gas production. yui This represents the predicted daily gas production for day i.

[0018] Preferably, the unit gas consumption cost and the total investment return rate are calculated using the following expressions:

[0019]

[0020] Where ΔQ represents the total increased gas production, C represents the cost per cubic meter of gas consumed, C1 represents the sum of the equipment and installation costs of the gas lift devices used in different operating schemes, C2 represents the operating cost of different gas lift devices, C3 represents the maintenance cost of different gas lift devices, and q gi q represents the measured daily gas production on day i of construction. g0 ε represents the initial daily gas production, ε represents the preset daily production decline rate per well, i represents the number of construction days, C4 represents the natural gas price excluding tax, ROI represents the total return on investment, and q represents the initial daily gas production. yui This represents the predicted daily gas production for day i.

[0021] On the other hand, embodiments of the present invention provide a system for evaluating gas lift technology in water-producing gas wells, comprising: a process evaluation factor generation module configured to obtain a discharge factor and a production enhancement factor characterizing the discharge and production enhancement features of the gas lift technology based on the production data of the water-producing gas well; a process effect condition generation module configured to obtain the operating condition of the gas lift technology of the current gas well based on the discharge factor and the production enhancement factor using a pre-constructed discharge-production relationship model; an operation plan benefit index generation module configured to obtain a benefit index for each alternative operation plan based on the operation data of each alternative operation plan of the current gas lift technology and the production data when the operating condition is a first type of operating condition; and an operation plan adjustment module configured to optimize the gas production strategy of the current water-producing gas well gas lift technology based on the benefit index of each alternative operation plan, so that the gas lift device of the current water-producing gas well operates according to the optimal gas production strategy.

[0022] Compared with the prior art, one or more embodiments of the above solutions may have the following advantages or beneficial effects:

[0023] This invention proposes a method and system for evaluating gas lift technology in water-producing gas wells. The method and system, through a model of the relationship between fluid drainage and production enhancement, obtain the operating conditions of the gas lift technology. When the operating conditions are effective for either production enhancement or fluid drainage, the system further calculates the benefit index and determines the optimal gas production strategy based on the benefit index. This achieves accurate evaluation of both production enhancement and fluid drainage effects without increasing surface investment, solving the problem of a single evaluation index for gas well performance. Furthermore, by determining the optimal gas production strategy through the benefit index of all alternative schemes, it enables comparison and selection among different operating schemes of the gas lift technology, improving the decision-making level of the gas lift technology, enhancing the intelligence level of the gas lift control system, and simultaneously improving economic efficiency.

[0024] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims and drawings. Attached Figure Description

[0025] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0026] Figure 1 This is a schematic diagram of the steps in a method for evaluating a gas lift process in a water-producing gas well, according to an embodiment of this application.

[0027] Figure 2 This is an example diagram illustrating the relationship between fluid discharge and production enhancement in a method for evaluating the gas lift process of a water-producing gas well, as described in an embodiment of this application.

[0028] Figure 3 This is a schematic diagram of the system for evaluating the gas lift process of a water-producing gas well, according to an embodiment of this application. Detailed Implementation

[0029] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings and examples, so that the process of how the present invention uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that, as long as there is no conflict, the various embodiments and features in the various embodiments of the present invention can be combined with each other, and the resulting technical solutions are all within the protection scope of the present invention.

[0030] Furthermore, the steps illustrated in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Also, although a logical order is shown in the flowcharts, in some cases the steps shown or described may be performed in a different order than that shown here.

[0031] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments. Unless the context clearly indicates otherwise, the singular forms “a” and “an” as used herein are also intended to include the plural. It should also be understood that the terms “comprising” and / or “including” as used herein specify the presence of the stated features, integers, steps, operations, units, and / or components, without excluding the presence or addition of one or more other features, integers, steps, operations, units, components, and / or combinations thereof.

[0032] In recent years, with the continuous expansion of the application of intelligent gas lift technology in water-producing gas wells, a series of intelligent gas lift devices and control systems have emerged. However, the current evaluation methods for intelligent gas lift technology mainly rely on changes in single indicators such as gas production, liquid production, and oil-casing pressure difference to evaluate the process effect.

[0033] However, existing evaluation methods face the following challenges: First, if the trends of different indicators are inconsistent, it is often difficult to determine the effectiveness, and there is no unified quantitative evaluation index; second, there is a lack of process effect evaluation methods that simultaneously consider drainage, production increase, and economic efficiency; and finally, it is difficult to compare and select among multiple drainage and gas production processes for the same well, resulting in the determined gas lift process being non-optimal.

[0034] Figure 1 This is a schematic diagram of the steps involved in evaluating the gas lift process for producing gas wells. See below for reference. Figure 1 The specific steps and flow of the method for evaluating the gas lift process of a water-producing gas well, as described in the embodiments of the present invention, will be explained.

[0035] Step S110: Based on the production data of the water-producing gas well, obtain the discharge factor and production enhancement factor that characterize the discharge and production enhancement features of the gas lift process.

[0036] Production data of the gas wells to be evaluated are collected, and based on the collected production data, a drainage factor characterizing the drainage characteristics of the gas lift process is calculated using an expression, and a production enhancement factor characterizing the production enhancement characteristics of the gas lift process is also calculated using an expression. In this way, both drainage and production enhancement characteristics are considered in the evaluation of the gas lift process, making the evaluation results of the gas lift process more accurate.

[0037] In this embodiment, when collecting production data from water-producing gas wells, the well casing wing outlet is connected to the gas lift drainage device, and the control system collects the daily wellhead oil pressure, wellhead casing pressure, daily gas production, and daily water production of the gas well. Specifically, the production data includes, but is not limited to: the daily wellhead oil pressure, wellhead casing pressure, daily gas production, daily water production, and production time of the water-producing gas well.

[0038] In this embodiment, the specific methods of obtaining the drainage factor and the yield-increasing factor are not limited, and can be reasonably selected according to actual application needs.

[0039] Optionally, to make the calculated drainage factor and production enhancement factor more accurate, the real-time wellbore liquid accumulation can be obtained from the production data of the water-producing gas wells, thereby obtaining the drainage factor, and the production enhancement factor can be obtained by setting the daily decline rate of single-well production for the gas well. Specifically, step S110 includes the following sub-steps A1-A3:

[0040] Sub-step A1: Based on the production data of the water-producing gas well to be evaluated, the pressure drop of the tubing annulus, the pressure drop of the tubing module, and the pressure drop of the tubing-carried fluid are obtained using a gas-liquid two-phase flow model, and the real-time wellbore fluid accumulation is further obtained.

[0041] Sub-step A2 calculates the initial discharge rate of the water-producing gas well and the real-time discharge rate based on the real-time wellbore liquid accumulation, thereby obtaining the discharge factor based on the initial discharge rate and the real-time discharge rate.

[0042] Sub-step A3: Set the daily decline rate of single-well production of gas wells, predict the real-time daily gas production of gas wells, and obtain the production enhancement factor based on the predicted and measured values ​​of daily gas production.

[0043] Furthermore, in sub-step A1, the real-time wellbore fluid accumulation volume is calculated using the following expression:

[0044]

[0045] Among them, Q ji P represents the real-time wellbore fluid accumulation. ci P represents the measured wellhead oil pressure on day i of construction. tiΔP represents the measured wellhead casing pressure on day i of construction. ani Indicates the pressure drop of the tubing annulus, ΔP fi Indicates the pressure drop due to friction in the oil pipe, ΔP li This indicates the hydraulic pressure drop across the oil pipe, where A represents the cross-sectional area of ​​the oil pipe, ρ. L represents the wellbore liquid phase density, and g represents the gravity acceleration.

[0046] Furthermore, in sub-step A2, the drainage factor is calculated using the following expression:

[0047]

[0048] Where, α i represents the drainage factor, q wi q represents the real-time drainage volume on day i of construction. w0 Q represents the initial drainage volume. j0 Q represents the initial wellbore fluid volume. ji η represents the real-time wellbore fluid accumulation. i η0 represents the real-time drainage rate, and η0 represents the initial drainage rate.

[0049] When i starts taking values ​​from the day before construction begins, the initial value i = 0. When i = 0, it represents the initial time, and the corresponding value is the initial value. When i is the i-th day of construction, it represents the real-time time, and the corresponding value is the real-time value.

[0050] Furthermore, in sub-step A3, the yield increase factor is calculated using the following expression:

[0051] q yui =q g0 *(1-ε) i (5)

[0052]

[0053] Where, λ i q represents the production increase factor. gi q represents the measured daily gas production on day i of construction. g0 ε represents the initial daily gas production, ε represents the preset daily production decline rate per well, i represents the number of days of construction, and q represents the initial daily gas production. yui This represents the predicted daily gas production for day i.

[0054] Step S120: Based on the drainage factor and production enhancement factor, the operating conditions of the gas lift process of the current gas well are obtained using a pre-constructed model of the relationship between drainage and production enhancement.

[0055] First, a model of the relationship between drainage and production enhancement is constructed based on the historical relationship between drainage factors and production enhancement factors and operating conditions. Then, based on the drainage factors and production enhancement factors of the gas lift process, the constructed model of the relationship between drainage and production enhancement is used for analysis to obtain the current operating conditions of the gas lift process of the gas well.

[0056] The model for the relationship between wastewater discharge and increased production includes an effective zone for increased production, an effective zone for wastewater discharge, and a zone where the process is ineffective. In one embodiment, the model for the relationship between wastewater discharge and increased production can be represented using a diagram.

[0057] The process of constructing the model of the relationship between drainage and increased production includes the following steps B1-B3:

[0058] Step B1: When the discharge factor is less than or equal to the first threshold and the production increase factor is less than or equal to the second threshold, the operating condition is that the process is invalid.

[0059] Step B2: When the drainage factor is greater than the first threshold and the production increase factor is less than or equal to the second threshold, the operating condition is that drainage is effective.

[0060] Step B3: When the discharge factor is greater than the first threshold and the production increase factor is greater than the second threshold, the operating condition is considered to be effective for production increase.

[0061] Specifically, when the gas lift process of the current gas well is ineffective, the control system sends a message to the staff indicating insufficient drainage intensity and suggests switching to other drainage and gas production processes; when the gas lift process of the current gas well is effective in draining liquid, the gas lift device corresponding to the gas lift process continues to operate, but the operating parameters of the gas lift process need to be adjusted to improve the production enhancement effect of the gas well; when the gas lift process of the current gas well is effective in enhancing production, the gas lift device corresponding to the gas lift process continues to operate, and there is no need to adjust the operating parameters of the gas lift device.

[0062] In step B1, the specific values ​​of the first threshold and the second threshold are not limited and can be reasonably selected according to the actual application requirements.

[0063] Furthermore, in order to make the operating conditions of the gas lift process of the current gas well more accurate by constructing the model of the relationship between drainage and production increase, it is preferable that both the first threshold and the second threshold are 1.

[0064] Optionally, Figure 2 A graphical example of the constructed model showing the relationship between wastewater discharge and increased production is provided. In this model, Zone I represents the effective zone for increased production, Zone II represents the effective zone for wastewater discharge, and Zone III represents the zone where the process is ineffective. (Reference) Figure 2 The first threshold is a threshold for the drainage factor used to distinguish between the effective drainage zone and the ineffective process zone, and the second threshold is a threshold for the production factor used to distinguish between the second type of operating condition and the effective production zone. The second type of operating condition includes the effective drainage zone and the ineffective process zone.

[0065] Step S130: When the operating condition is the first type of operating condition, obtain the revenue index of each alternative operating scheme based on the operating data and production data of each alternative operating scheme of the current air lift process.

[0066] The method for evaluating the gas lift process of water-producing gas wells in this embodiment comprehensively considers both liquid drainage and production enhancement. Only when the operating conditions meet the requirements will the efficiency index of each alternative operating scheme be obtained based on the operating data and production data of the alternative operating schemes that meet the requirements, thereby facilitating the comparison between different alternative operating schemes.

[0067] In this embodiment, the current gas lift process includes a single gas lift process and a combined gas lift process. The single gas lift process is selected from one of the following: compressor gas lift process, gas lift valve gas lift process, plunger gas lift process, inter-well gas lift process, skid-mounted gas lift process, and tank truck gas lift process. The combined gas lift process includes: a combination of multiple single gas lift processes and a combination of a single gas lift process and a bubble discharge process.

[0068] In this embodiment, in order to enable the evaluation method of the air lift process to accurately evaluate the dual effects of increased production and liquid drainage, and considering the benefit index, it is preferable that both the effective area for increased production and the effective area for liquid drainage belong to the first type of operating condition, and that the ineffective area of ​​the process belongs to the second type of operating condition.

[0069] In this embodiment, when acquiring operational data for the operational plan, factors need to be considered, including the purchase cost of the gas lift equipment used in the operational plan, the residual value rate of the gas lift equipment, the comprehensive depreciation period of the gas lift equipment, the power of the gas lift equipment, the daily operating time of the gas lift equipment, and the maintenance cost of the gas lift equipment. External factors such as industrial electricity costs and the price of natural gas excluding tax also need to be considered. Specifically, the operational data for each alternative operational plan includes: the purchase cost of the gas lift equipment used in different operational plans, the residual value rate of different gas lift equipment, the daily operating time of different gas lift equipment, the maintenance cost of different gas lift equipment, and the price of natural gas excluding tax.

[0070] In this embodiment, to ensure that the selected operating scheme maximizes the benefits of the water-producing gas well, both consumption costs and return on investment can be considered comprehensively. Specifically, the return on investment indicators include the cost per cubic meter of gas consumed and the total return on investment.

[0071] The unit gas consumption cost and the total investment return rate are calculated using the following expressions:

[0072]

[0073] Where ΔQ represents the total increased gas production, C represents the cost per cubic meter of gas consumed, C1 represents the sum of the equipment and installation costs of the gas lift devices used in different operating schemes, C2 represents the operating cost of different gas lift devices, C3 represents the maintenance cost of different gas lift devices, and q gi q represents the measured daily gas production on day i of construction. g0 ε represents the initial daily gas production, ε represents the preset daily production decline rate per well, i represents the number of construction days, C4 represents the natural gas price excluding tax, ROI represents the total return on investment, and q represents the initial daily gas production. yui This represents the predicted daily gas production for day i.

[0074] The gas lift devices used in different operating schemes can be obtained by purchasing or by leasing; the operating costs of different gas lift devices include the electricity cost or the gas cost of the gas lift device.

[0075] In this embodiment, in order to further improve the efficiency of the water-producing gas well, the process type should be changed in a timely manner when the current gas lift process of the gas well is an ineffective process. Specifically, when the operating condition is the second type of operating condition, the gas lift process of the current water-producing gas well should be changed.

[0076] Step S140: Based on the revenue indicators of each alternative operating scheme, select the optimal gas production strategy for the current water-producing gas well gas lift process, so that the gas lift device of the current water-producing gas well operates according to the optimal gas production strategy.

[0077] After calculating the benefit index of each alternative operating scheme, the benefit indexes of different alternative operating schemes are compared. Based on the comparison results, the optimal gas production strategy of the current water-producing gas well gas lift process is selected. In order to maximize the benefits of the water-producing gas well, the gas lift device of the water-producing gas well can be operated according to the selected optimal gas production strategy after the optimal gas production strategy is obtained.

[0078] In this embodiment, the specific method for obtaining the optimal strategy is not limited, and can be reasonably selected according to the actual application requirements.

[0079] Optionally, to ensure the optimal gas extraction strategy is accurately and simply obtained, it is preferable to set thresholds through different operating schemes, and then compare the profitability indicators of alternative schemes with the thresholds to obtain the optimal gas extraction strategy. Specifically, step S140 includes the following sub-step C1:

[0080] Sub-step C1: When the unit gas consumption cost of a candidate operating scheme is less than a preset unit gas consumption cost threshold, and the total investment return rate is greater than a preset total investment return rate threshold, the current operating scheme is determined as the optimal gas extraction strategy.

[0081] To maximize the efficiency of the water-producing gas wells, the optimal gas extraction strategy is selected based on the operating scheme with the lowest unit gas consumption cost and the highest total return on investment. Specifically, the preset unit gas consumption cost threshold is determined based on the minimum unit gas consumption cost among all alternative operating schemes, and the preset total return on investment threshold is determined based on the maximum total return on investment among all alternative operating schemes.

[0082] Figure 3 This is a schematic diagram of a system for evaluating the gas lift process of a water-producing gas well, according to an embodiment of this application. Figure 3 As shown in the embodiment of the present invention, the system for evaluating the gas lift process of a water-producing gas well includes: a process evaluation factor generation module 301, a process effect condition generation module 302, an operation plan benefit index generation module 303, and an operation plan adjustment module 304.

[0083] Specifically, the process evaluation factor generation module 301 is implemented according to the method described in step S110 above, and is configured to obtain the discharge factor and production enhancement factor characterizing the discharge and production enhancement features of the gas lift process based on the production data of the water-producing gas well; the process effect condition generation module 302 is implemented according to the method described in step S120 above, and is configured to obtain the operating condition of the gas lift process of the current gas well based on the discharge factor and production enhancement factor and using a pre-constructed discharge and production enhancement relationship model; the operation plan benefit index generation module 303 is implemented according to the method described in step S130 above, and is configured to obtain the benefit index of each alternative operation plan based on the operation data and production data of each alternative operation plan of the current gas lift process when the operating condition is the first type of operating condition; the operation plan adjustment module 304 is implemented according to the method described in step S140 above, and is configured to select the best gas production strategy for the gas lift process of the current water-producing gas well based on the benefit index of each alternative operation plan, so that the gas lift device of the current water-producing gas well operates according to the best gas production strategy.

[0084] This invention discloses a method and system for evaluating gas lift technology in water-producing gas wells. The method and system obtain the operating conditions of the gas lift technology through a model of the relationship between fluid drainage and increased production. When the operating conditions are effective for either increased production or effective for fluid drainage, the system further calculates the benefit index and determines the optimal gas production strategy based on the benefit index. This achieves accurate evaluation of both increased production and fluid drainage effects without increasing surface investment, solving the problem of a single evaluation index for gas well performance. Furthermore, by determining the optimal gas production strategy through the benefit index of all alternative schemes, it enables comparison and selection among multiple operating schemes, improving the decision-making level of the gas lift technology, enhancing the intelligence level of the gas lift control system, and simultaneously improving economic efficiency.

[0085] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

[0086] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0087] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0088] It should be understood that the embodiments disclosed herein are not limited to the specific structures, processing steps, or materials disclosed herein, but should be extended to equivalent substitutions of these features as understood by those skilled in the art. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0089] The phrase "an embodiment" or "an embodiment" used in this specification means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Therefore, the phrase "an embodiment" or "an embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment.

[0090] The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

[0091] While the embodiments disclosed in this invention are as described above, the content is merely for the purpose of facilitating understanding of the invention and is not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and changes in form and detail of the implementation without departing from the spirit and scope disclosed herein; however, the scope of patent protection of this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A method for evaluating gas lift technology in water-producing gas wells, characterized in that, include: Based on the production data of the water-producing gas wells, the discharge factor and production enhancement factor characterizing the discharge and production enhancement features of the gas lift process were obtained. Based on the drainage factor and the production enhancement factor, the operating conditions of the gas lift process of the current gas well are obtained using a pre-constructed model of the relationship between drainage and production enhancement. When the operating condition is the first type of operating condition, the revenue index of each alternative operating scheme is obtained based on the operating data of each alternative operating scheme of the current air lift process and the production data. Based on the profitability indicators of each alternative operating scheme, the optimal gas production strategy for the current water-producing gas well gas lift process is selected so that the gas lift device of the current water-producing gas well operates in accordance with the optimal gas production strategy.

2. The method according to claim 1, characterized in that, When the operating condition is the second type, the gas lift process of the current water-producing gas well is replaced.

3. The method according to claim 2, characterized in that, The model for the relationship between drainage and production enhancement includes an effective production enhancement zone, an effective drainage zone, and a process ineffective zone. The step of obtaining the operating conditions of the gas lift process for the current gas well based on the drainage factor and the production enhancement factor using the pre-constructed model includes: When the discharge factor is less than or equal to the first threshold and the production increase factor is less than or equal to the second threshold, the operating condition is an invalid process. When the drainage factor is greater than the first threshold and the production increase factor is less than or equal to the second threshold, the operating condition is effective for drainage. When the drainage factor is greater than the first threshold and the production increase factor is greater than the second threshold, the operating condition is considered to be effective in increasing production.

4. The method according to claim 3, characterized in that, Both the effective production increase zone and the effective drainage zone belong to the first type of operating condition; and The ineffective process zone belongs to the second type of operating condition.

5. The method according to any one of claims 1 to 4, characterized in that, The profitability indicators include: unit gas consumption cost and total investment return rate. The step of selecting the optimal gas production strategy for the current water-producing gas well gas lift process based on the profitability indicators of each alternative operating scheme includes: When the unit gas consumption cost of a certain alternative operating scheme is less than a preset unit gas consumption cost threshold, and the total investment return rate is greater than a preset total investment return rate threshold, the current operating scheme is determined as the optimal gas extraction strategy. The preset unit gas consumption cost threshold is determined based on the minimum unit gas consumption cost of all alternative operating schemes, and the preset total investment return rate threshold is determined based on the maximum total investment return rate of all alternative operating schemes.

6. The method according to any one of claims 1 to 5, characterized in that, The steps of obtaining the drainage factor and production enhancement factor, which characterize the drainage and production enhancement features of the gas lift process, based on the production data of the water-producing gas wells, include: Based on the production data of the water-producing gas well, the pressure drop of the tubing annulus, the pressure drop of tubing friction, and the pressure drop of tubing carrying capacity are obtained using a gas-liquid two-phase flow model, and the real-time wellbore liquid accumulation is further obtained. The initial discharge rate of the gas well is calculated, and the real-time discharge rate is calculated based on the real-time wellbore fluid accumulation, thereby obtaining the discharge factor based on the initial discharge rate and the real-time discharge rate. The daily decline rate of single-well production is set, and the real-time daily gas production of the gas well is predicted. Then, the production enhancement factor is obtained based on the predicted and measured values ​​of the daily gas production.

7. The method according to claim 6, characterized in that, The drainage factor is calculated using the following expression: Where, α i represents the drainage factor, q wi q represents the real-time drainage volume on day i of construction. w0 Q represents the initial drainage volume. j0 Q represents the initial wellbore fluid volume. ji η represents the real-time wellbore fluid accumulation. i η0 represents the real-time drainage rate on day i of construction, and η0 represents the initial drainage rate.

8. The method according to claim 6 or 7, characterized in that, The production enhancement factor is calculated using the following expression: what yui =q go *(1-ε) i Where, λ i q represents the production increase factor. gi q represents the measured daily gas production on day i of construction. g0 ε represents the initial daily gas production, ε represents the preset daily production decline rate per well, i represents the number of days of construction, and q represents the initial daily gas production. yui This represents the predicted daily gas production for day i.

9. The method according to claim 5, characterized in that, The unit gas consumption cost and the total investment return rate are calculated using the following expressions: Where ΔQ represents the total increased gas production, C represents the cost per cubic meter of gas consumed, C1 represents the sum of the equipment and installation costs of the gas lift devices used in different operating schemes, C2 represents the operating cost of different gas lift devices, C3 represents the maintenance cost of different gas lift devices, and q gi q represents the measured daily gas production on day i of construction. g0 ε represents the initial daily gas production, ε represents the preset daily production decline rate per well, i represents the number of construction days, C4 represents the natural gas price excluding tax, ROI represents the total return on investment, and q represents the initial daily gas production. yui This represents the predicted daily gas production for day i.

10. A system for evaluating gas lift technology in water-producing gas wells, characterized in that, include: The process evaluation factor generation module is configured to obtain the discharge factor and production enhancement factor characterizing the discharge and production enhancement features of the gas lift process based on the production data of the water-producing gas wells. The process effect condition generation module is configured to obtain the current gas lift process condition of the gas well based on the drainage factor and the production enhancement factor, using a pre-built drainage and production enhancement relationship model. The operation plan revenue index generation module is configured to, when the operating condition is the first type of operating condition, obtain the revenue index of each alternative operation plan based on the operating data of each alternative operation plan of the current gas lift process and the production data. The operation plan adjustment module is configured to select the optimal gas production strategy for the current water-producing gas well gas lift process based on the benefit index of each alternative operation plan, so that the gas lift device of the current water-producing gas well operates according to the optimal gas production strategy.

Images