Single-well yield and recoverable reserve prediction method and device, storage medium, and terminal

Abstract

A single-well yield and recoverable reserve prediction method and device. The method comprises: acquiring production data of a production well and a total injection amount of a fracturing fluid, and preprocessing the production data; selecting a historical data time stage for fitting, and on the basis of fitting by using a cumulative yield and a flowback rate at each moment in the historical data time stage, determining a relation between the cumulative yield and the flowback rate at each moment; selecting a historical data time stage for fitting, and on the basis of fitting by using a flowback rate and time of the historical data time stage, determining a relation between the flowback rate and time; setting extension time, and on the basis of the determined relation between the flowback rate and the time, determining a flowback rate at a future moment after the extension time; on the basis of the flowback rate after the extension time and the determined relation between the cumulative yield and the flowback rate at each moment, determining a cumulative yield at the future moment after the extension; and on the basis of the extension time and the cumulative yield at the future moment after the extension time, calculating a daily yield at the future moment.

Description

Single well production and recoverable reserves prediction method, device, storage medium and terminal Technical Field

[0001] The present invention relates to the field of oil and gas field development, and in particular to a method, device, storage medium and terminal for predicting single well production and recoverable reserves. Background Art

[0002] In the current field of oil and gas field development technology, production prediction is a key research area. Currently, the commonly used production prediction methods at home and abroad mainly include empirical methods, analytical methods, numerical simulation methods, and machine learning-based production prediction methods.

[0003] Empirical methods are widely popular due to their simplicity and reasonable prediction results. This is particularly true in complex unconventional oil and gas reservoir systems, such as those involving multi-stage fractured horizontal well completions. Engineers favor empirical methods, which can provide reasonable production forecasts for individual wells based on simple time-to-production relationships. These methods are typically based on historical data, predicting future production by observing and summarizing past patterns. This approach relies on an understanding of historical data and empirical judgment, offering the advantage of rapid results.

[0004] Analytical methods require reservoir simplification and input parameters with high uncertainty for production forecasting, thus limiting their application. Analytical methods are based on specific physical models and mathematical formulas, using analytical solutions to predict production. This approach requires advanced physics knowledge and computational skills, as well as high parameter accuracy.

[0005] Numerical simulation methods are computationally intensive, difficult to perform, inefficient, and suffer from high uncertainty in their results, limiting their application. Numerical simulation methods simulate reservoir physical processes to predict production, allowing for more influencing factors. However, they are computationally intensive and require high computer resources.

[0006] Yield forecasting methods based on machine learning require large amounts of data and complex algorithms. Prediction accuracy is closely related to the amount and quality of the data, resulting in a high degree of uncertainty. Machine learning methods analyze large amounts of historical data, allowing the model to learn patterns and regularities within the data, thereby enabling yield forecasting.

[0007] In recent years, new decline curve models specifically tailored for multi-stage fractured horizontal well completions (shale / tight oil wells) have been proposed and widely used. However, different empirical decline curve models have different applicable conditions and phases. Generally, engineers need to preprocess data, diagnose flow patterns, and select appropriate prediction methods. This involves a complex process and requires a high level of expertise. Furthermore, these empirical methods require at least two years of historical production data to provide a reasonable forecast of future production.

[0008] Furthermore, the aforementioned empirical methods all rely on historical production data to predict future production. However, in actual production, oil and gas well performance is often affected by numerous factors, such as geological conditions and stimulation measures. Therefore, future production predictions based solely on historical production often fail to fully account for the impact of these factors on production forecasts, resulting in limitations and poor accuracy.

[0009] Currently, user demands are growing. They want to be able to predict individual well production and future recoverable reserves well in advance, and they want the prediction methods to be simple, easy to use, and produce results quickly. Furthermore, users want the prediction results to be highly accurate to facilitate subsequent decision-making and development planning.

[0010] Summary of the Invention

[0011] Based on this, it is necessary to provide a single well production and recoverable reserves prediction method, device, storage medium and terminal to address at least some of the above problems.

[0012] A method for predicting single well production and recoverable reserves, comprising:

[0013] Obtain production data and total injection volume of fracturing fluid from production wells, and pre-process the production data;

[0014] Selecting a historical data time period for fitting, and determining a relationship between the cumulative production and the flowback rate at each moment based on the cumulative production and the flowback rate at each moment in the historical data time period;

[0015] Selecting a time period of historical data for fitting, and determining a relationship between the flowback rate and time based on the flowback rate and time fitting in the time period of the historical data;

[0016] Setting an extension time, and determining the return rate at a future time after the extension time based on the determined relationship between the return rate and time;

[0017] Determining the cumulative production at a future time after the extended time based on the flowback rate after the extended time and the determined relationship between the cumulative production at each time and the flowback rate;

[0018] Based on the extended time and the cumulative output at future times after the extended time, the daily output at future times is calculated.

[0019] Optionally, the preprocessing of the production data includes:

[0020] Determine the flowback rate at each moment based on the cumulative water production and the total injection volume of fracturing fluid at each moment;

[0021] Determine the time logarithm corresponding to each moment based on the accumulated production time at each moment;

[0022] A flowback rate function at each moment is determined based on the flowback rate at each moment.

[0023] Optionally, the step of fitting the cumulative production and flowback rate at each moment in the historical data time period to determine the relationship between the cumulative production and flowback rate at each moment may include:

[0024] Draw a scatter plot of the cumulative production and flowback rate at each moment in the historical data time period;

[0025] Based on the scatter plot of the cumulative production at each moment and the flowback rate, a first fitting formula for characterizing the relationship between the cumulative production at each moment and the flowback rate is obtained by fitting.

[0026] Optionally, the determining the relationship between the flowback rate and time based on the flowback rate of the time period of historical data and time fitting includes:

[0027] Draw a scatter plot of the flowback rate and time during the historical data period;

[0028] Based on the scatter plot of the flowback rate and time, a second fitting formula for characterizing the relationship between the flowback rate and time is obtained by fitting.

[0029] Optionally, the step of determining the flowback rate at a future time after the extended time based on the determined relationship between the flowback rate and time includes:

[0030] Will extend the time t i Substitute into the second fitting formula to calculate the extension time t i The return rate at future times.

[0031] Optionally, determining the cumulative production at a future time after the extended time based on the flowback rate after the extended time and the determined relationship between the cumulative production at each time and the flowback rate includes:

[0032] Substitute the flowback rate into the first fitting formula to obtain the extended time t i The cumulative output at future times.

[0033] A single well production and recoverable reserves prediction device, comprising:

[0034] A preprocessing module is used to obtain production data of production wells and the total injection volume of fracturing fluid, and to preprocess the production data;

[0035] A first fitting module is used to select a historical data time period for fitting, and determine the relationship between the cumulative production and the flowback rate at each moment in the historical data time period based on the cumulative production and the flowback rate at each moment;

[0036] A second fitting module is used to select a time period of historical data for fitting, and determine a relationship between the flowback rate and time based on the flowback rate and time fitting of the time period of the historical data;

[0037] A flowback rate calculation module, configured to determine the flowback rate at a future time after the extended time based on the set extended time and the relationship between the determined flowback rate and time;

[0038] a cumulative production calculation module, configured to determine the cumulative production at a future moment after the extended time based on the flowback rate after the extended time and the relationship between the cumulative production and the flowback rate at each moment;

[0039] The daily output calculation module is used to calculate the daily output at a future time based on the extended time and the cumulative output at a future time after the extended time.

[0040] A storage medium stores a computer program, which, when executed by a processor, implements the single-well production and recoverable reserves prediction method.

[0041] A terminal comprising: a processor and a memory;

[0042] The memory is used to store computer programs;

[0043] The processor is used to execute the computer program stored in the memory, so that the terminal executes the single well production and recoverable reserves prediction method.

[0044] The above-mentioned single well production and recoverable reserves prediction method and device have at least the following beneficial technical effects:

[0045] In summary, the present invention provides a method, device, storage medium, and terminal for predicting single-well production and recoverable reserves based on the flowback rate. The method introduces the flowback rate as a factor, takes into account the impact of factors such as production stimulation measures on production prediction, and solves the problems existing in the prior art by specifically studying the relationship between the cumulative production of a single well and the flowback rate, as well as the relationship between the flowback rate of a single well and time.

[0046] This method uses a small amount of historical production data from the previous six months or year, combined with historical flowback rates, to provide a more reasonable forecast of future daily production. Comparison with actual production reveals high accuracy. This method can accurately predict future daily production and recoverable reserves for individual wells, providing a reliable reference for future production planning.

[0047] In addition, this method reduces the demand for data and computing resources, requiring only historical production data from the previous six months or one year, greatly reducing data requirements and improving prediction efficiency.

[0048] This method also simplifies the analysis steps, reduces the professional requirements for engineers, and provides a more efficient solution for production forecasting.

[0049] Based on the above reasons, the present invention fully demonstrates the advantages of the empirical method of using early production data to make reasonable output forecasts in practical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] FIG1 is a flow chart of a method for predicting single well production and recoverable reserves according to the present invention;

[0051] FIG2 is a partial flow chart of step S101 in the method for predicting single well production and recoverable reserves of the present invention;

[0052] FIG3 is a flow chart of step S102 in the method for predicting single well production and recoverable reserves of the present invention;

[0053] FIG4 is a flow chart of step S103 in the method for predicting single well production and recoverable reserves of the present invention;

[0054] FIG5 is a schematic diagram of the present invention showing the relationship between the cumulative production and the flowback rate at each moment determined by fitting the cumulative production and the flowback rate at each moment in the historical data time period;

[0055] FIG6 is a schematic diagram of the relationship between flowback rate and time (oil well) determined based on the flowback rate of the historical data time stage and time fitting according to the present invention;

[0056] FIG7 is a schematic diagram of the relationship between flowback rate and time (gas well) determined based on the flowback rate of the historical data time stage and time fitting according to the present invention;

[0057] FIG8 is a detailed logic flow chart of the present invention. DETAILED DESCRIPTION

[0058] The present invention will be further described below with reference to the accompanying drawings.

[0059] To facilitate understanding of the present invention, various embodiments defined in the claims of the present invention will be described more fully below with reference to the relevant drawings. Preferred embodiments of the present invention are shown in the drawings, which contain various specific details to assist in such understanding, but these details should be considered as merely exemplary. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Accordingly, those of ordinary skill in the art will recognize that changes and improvements may be made to the various embodiments described herein without departing from the scope of the present invention as defined by the appended claims. In addition, descriptions of well-known functions and configurations may be omitted for clarity and brevity.

[0060] It will be apparent to those skilled in the art that the following description of various embodiments of the present invention is provided for the purpose of illustration only and not for the purpose of limiting the invention as defined by the appended claims.

[0061] Throughout the specification and claims of this application document, the words "comprise" and "include" and variations of the words, such as "including" and "comprising" mean "including but not limited to", and are not intended to (and will not) exclude other components, integers or steps. Features, integers or characteristics described in conjunction with a particular aspect, embodiment or example of the invention will be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith.

[0062] It should be understood that the singular forms "a", "an", and "the" include plural references unless the context clearly dictates otherwise. The expressions "including" and / or "may include" as used in the present invention are intended to indicate the presence of corresponding functions, operations, or elements, and are not intended to limit the presence of one or more functions, operations, and / or elements. In addition, in the present invention, the terms "including" and / or "having" are intended to indicate the presence of the characteristics, quantities, operations, elements, and components disclosed in the application documents, or a combination thereof. Therefore, the terms "including" and / or "having" should be understood as additional possibilities of the presence of one or more other characteristics, quantities, operations, elements, and components, or a combination thereof.

[0063] In the present invention, the expression "or" includes any or all combinations of the words listed together. For example, "A or B" may include A or B, or may include both A and B.

[0064] It should be understood that when an element is referred to as being “fixed to” another element, it can be directly on the other element or there may also be an intervening element; when an element is considered to be “connected” or “coupled” to another element, it can be directly connected or coupled to the other element or there may also be an intervening element.

[0065] The terms "up", "down", "left", "right", etc. mentioned in the text are only used to indicate relative position relationships. When the absolute position of the described object changes, the relative position relationship may also change accordingly.

[0066] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention pertains. It should also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with the context of the relevant art and this specification, and should not be interpreted in an idealized or overly formal sense unless explicitly defined as such herein. The term "and / or" as used herein includes any and all combinations of one or more of the relevant listed items.

[0067] As shown in FIG1 , in one embodiment of the present invention, a method for predicting single-well production and recoverable reserves is provided, comprising:

[0068] S101: Acquire production data of production wells and the total injection volume of fracturing fluid, and pre-process the production data.

[0069] Referring to FIG2 , in some embodiments, preprocessing the production data includes:

[0070] S201: determining a flowback rate at each moment based on the cumulative water production and the total injection volume of the fracturing fluid at each moment;

[0071] S202: Determine the time logarithm corresponding to each moment based on the accumulated production time at each moment;

[0072] S203: Determine a flow-back rate function at each moment based on the flow-back rate at each moment.

[0073] The production data obtained from the production wells includes the production at each moment, the cumulative production at each moment, and the cumulative water production at each moment. After obtaining the data, it is necessary to identify the rationality of the data based on the actual situation and conduct appropriate verification and correction.

[0074] Specifically, the production data is preprocessed, including:

[0075] Calculate the flowback rate at each moment: The flowback rate at each moment is calculated by dividing the cumulative water production at each moment by the total injection volume of the fracturing fluid. The calculation formula is: Where W p The cumulative water production at each moment, W i is the total injection volume of fracturing fluid;

[0076] Calculate the logarithm of time corresponding to each moment: Calculate the logarithm of time based on the cumulative production time at each moment. The calculation formula is ln(t), where t is the cumulative production time corresponding to each moment, and the initial production moment corresponds to t = 0;

[0077] Calculate the return rate function at each moment: According to the return rate at each moment, the return rate function at each moment is calculated. The calculation formula is: in is the flowback rate at each moment.

[0078] S102: Selecting a historical data time period for fitting, and determining the relationship between the cumulative production and the flowback rate at each moment in the historical data time period based on the cumulative production and the flowback rate at each moment in the fitting.

[0079] 3 and 5 , in some embodiments, the method of fitting the cumulative production and flowback rate at each moment in the historical data time period to determine the relationship between the cumulative production and flowback rate at each moment includes:

[0080] S301: Draw a scatter plot of the cumulative production and flowback rate at each moment in the historical data time period;

[0081] S302: Based on the scatter plot of the cumulative production and the flowback rate at each moment, a first fitting formula for characterizing the relationship between the cumulative production and the flowback rate at each moment is obtained by fitting.

[0082] Specifically, taking the oil well in Figure 5 as an example, a scatter plot is made with the horizontal axis representing the flowback rate and the vertical axis representing the cumulative oil production. After fitting, the first fitting formula is obtained as follows: where N p is the cumulative oil production at each moment; is the flowback rate at each moment.

[0083] For gas wells, a scatter plot is made with the horizontal axis being the flowback rate and the vertical axis being the cumulative gas production. After fitting, the first fitting formula is: Among them G p The cumulative gas production at each moment.

[0084] In this embodiment, first fitting formulas of the corresponding cumulative production and flowback rate at each moment are fitted for oil wells and gas wells, respectively, to ensure the accuracy of subsequent oil and gas production predictions.

[0085] S103: Selecting a time period of historical data for fitting, and determining a relationship between the flowback rate and time based on the flowback rate and time fitting in the time period of the historical data.

[0086] 4 , in some embodiments, the determining the relationship between the flowback rate and time based on the flowback rate of the time period of historical data and time fitting includes:

[0087] S401: Draw a scatter plot of the return flow rate and time during the historical data time period;

[0088] S402: Based on the scatter plot of the flowback rate and time, a second fitting formula for characterizing the relationship between the flowback rate and time is obtained by fitting.

[0089] Specifically, as shown in FIG6 , for an oil well, a scatter plot is drawn with the horizontal axis being the logarithm of time and the vertical axis being the flowback rate; after fitting, the second fitting formula is obtained: Where C and D are fitting parameters.

[0090] As shown in Figure 7, for a gas well, a scatter plot is drawn with time as the horizontal axis and the flowback rate function as the vertical axis; the second fitting formula is obtained by fitting: Where m and n are fitting parameters.

[0091] In this embodiment, the second fitting formulas for the corresponding flowback rate and time are fitted for the oil wells and gas wells respectively, which can ensure the accuracy of subsequent oil and gas production predictions.

[0092] S104: Setting an extension time, and determining the return rate at a future time after the extension time based on the determined relationship between the return rate and time.

[0093] In some embodiments, determining the flowback rate at a future time after the extended time based on the determined relationship between the flowback rate and time comprises:

[0094] Will extend the time t i Substitute into the second fitting formula to calculate the extension time t i The return rate at a later time

[0095] Specifically, after the relevant fitting parameters in the second fitting formula are determined, the relationship between the return rate and time is determined. At this time, the extended time t is introduced. i The extended time t can be obtained i The return rate at a later time (predicted value).

[0096] S105: Based on the flowback rate after the extension time and the determined relationship between the cumulative production and the flowback rate at each moment, determine the cumulative production at a future moment after the extension time.

[0097] In some embodiments, determining the cumulative production at a future time after the extended time based on the flowback rate after the extended time and the determined relationship between the cumulative production at each time and the flowback rate comprises:

[0098] The flowback rate (Predicted value) is substituted into the first fitting formula to obtain the extended time t i The cumulative output at future times (forecast value).

[0099] Specifically, after the relevant fitting parameters in the first fitting formula are determined, the relationship between the cumulative production and the flowback rate at each moment is determined. At this time, the flowback rate at the future moment is introduced. (Predicted value) can be used to obtain the cumulative output (predicted value) at future times.

[0100] S106: Based on the extended time and the cumulative production at the future time after the extended time, the daily production at the future time is calculated.

[0101] In some embodiments, the calculation of the daily production at a future time based on the extended time and the cumulative production at a future time after the extended time includes:

[0102] The calculation formula is: (for oil wells) or (For gas wells) Calculate daily production.

[0103] Among them, the subscript i is the extended time sequence number, is the daily oil production corresponding to the i-th moment, is the cumulative oil production corresponding to the i-th moment (predicted value), is the cumulative oil production (predicted value) corresponding to the (i+1)th moment, t i+1 is the cumulative production time corresponding to the (i+1)th moment, t i is the cumulative production time corresponding to the i-th moment, is the daily gas production corresponding to the i-th moment, is the cumulative gas production corresponding to the i-th moment (predicted value).

[0104] As shown in Figure 8, in response to the problems existing in the existing technology, this application introduces the factor of return flow rate, takes into account the impact of factors such as production stimulation measures on production prediction, and specifically studies the relationship between the cumulative production of a single well and the return flow rate, as well as the relationship between the return flow rate of a single well and time, and proposes a single well production and recoverable reserves prediction method based on the return flow rate.

[0105] The flowback rate-based single-well production and recoverable reserves prediction method provided by this invention utilizes a small amount of historical production data from the previous six months or year, combined with historical flowback rates, to provide a more reasonable forecast of future daily production. Comparison with actual results reveals high accuracy in the prediction results. This method can accurately predict future daily production and recoverable reserves for a single well, providing a reliable reference for future production planning.

[0106] In addition, this method reduces the demand for data and computing resources, requiring only historical production data from the previous six months or one year, greatly reducing data requirements and improving prediction efficiency.

[0107] This method also simplifies the analysis steps, reduces the professional requirements for engineers, and provides a more efficient solution for production forecasting.

[0108] Based on the above reasons, the present invention can take advantage of the practical application of the empirical method of making reasonable output forecasts by utilizing early production data.

[0109] The present invention also provides a single well production and recoverable reserves prediction device, comprising:

[0110] A preprocessing module is used to obtain production data of production wells and the total injection volume of fracturing fluid, and to preprocess the production data;

[0111] A first fitting module is used to select a historical data time period for fitting, and determine the relationship between the cumulative production and the flowback rate at each moment in the historical data time period based on the cumulative production and the flowback rate at each moment;

[0112] A second fitting module is used to select a time period of historical data for fitting, and determine a relationship between the flowback rate and time based on the flowback rate and time fitting of the time period of the historical data;

[0113] A flowback rate calculation module, configured to determine the flowback rate at a future time after the extended time based on the set extended time and the relationship between the determined flowback rate and time;

[0114] a cumulative production calculation module, configured to determine the cumulative production at a future moment after the extended time based on the flowback rate after the extended time and the relationship between the cumulative production and the flowback rate at each moment;

[0115] The daily output calculation module is used to calculate the daily output at a future time based on the extended time and the cumulative output at a future time after the extended time.

[0116] Since the principles and functions of each module in the above-mentioned shale oil and gas production prediction system correspond one-to-one to the steps of the above-mentioned shale oil and gas production prediction method, they will not be repeated here.

[0117] It should be understood that the division of the modules of the above devices is merely a division of logical functions. In actual implementation, they may be fully or partially integrated into a single physical entity or physically separated. Furthermore, these modules may be implemented entirely in software called by a processing element, or entirely in hardware. Alternatively, some modules may be implemented in software called by a processing element, while others may be implemented in hardware. For example, module x may be a separate processing element, or integrated into a chip of the above device. Furthermore, it may be stored in the form of program code in the memory of the above device, and called by a processing element of the device to perform the functions of module x. The implementation of other modules is similar. Furthermore, these modules may be fully or partially integrated or implemented independently. The processing element described herein may be an integrated circuit with signal processing capabilities. During implementation, the steps of the above method or the modules above may be performed by hardware integrated logic circuits in the processor element or by software instructions.

[0118] For example, the above modules may be one or more integrated circuits configured to implement the above methods, such as one or more application-specific integrated circuits (ASICs), one or more digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs). For another example, when a module is implemented by scheduling program code through a processing element, the processing element may be a general-purpose processor, such as a central processing unit (CPU) or other processor that can call program code. For another example, these modules may be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0119] The storage medium of the present invention stores a computer program that, when executed by a processor, implements the above-mentioned shale gas production prediction method. The storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disk, USB flash drive, memory card, or optical disk.

[0120] The terminal of the present invention includes a processor and a memory.

[0121] The memory is used to store computer programs. Preferably, the memory includes: ROM, RAM, magnetic disk, USB flash drive, memory card or optical disk, etc., various media that can store program codes.

[0122] The processor is connected to the memory and is used to execute the computer program stored in the memory so that the terminal executes the above-mentioned shale gas production prediction method.

[0123] Preferably, the processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0124] It should be noted that the single-well production and recoverable reserves prediction system of the present invention can implement the single-well production and recoverable reserves prediction method of the present invention, but the implementation device of the single-well production and recoverable reserves prediction method of the present invention includes but is not limited to the structure of the single-well production and recoverable reserves prediction device listed in this embodiment. All structural deformations and replacements of the existing technology made according to the principles of the present invention are included in the protection scope of the present invention.

[0125] In summary, the present invention provides a method, device, storage medium, and terminal for predicting single-well production and recoverable reserves based on the flowback rate. The method introduces the flowback rate as a factor, takes into account the impact of factors such as production stimulation measures on production prediction, and solves the problems existing in the prior art by specifically studying the relationship between the cumulative production of a single well and the flowback rate, as well as the relationship between the flowback rate of a single well and time.

[0126] This method uses a small amount of historical production data from the previous six months or year, combined with historical flowback rates, to provide a more reasonable forecast of future daily production. Comparison with actual production reveals high accuracy. This method can accurately predict future daily production and recoverable reserves for individual wells, providing a reliable reference for future production planning.

[0127] In addition, this method reduces the demand for data and computing resources, requiring only historical production data from the previous six months or one year, greatly reducing data requirements and improving prediction efficiency.

[0128] This method also simplifies the analysis steps, reduces the professional requirements for engineers, and provides a more efficient solution for production forecasting.

[0129] Based on the above reasons, the present invention fully demonstrates the advantages of the empirical method of using early production data to make reasonable output forecasts in practical applications.

[0130] In the above description, although expressions such as "first" and "second" may be used to describe various elements of the present invention, they are not intended to limit the corresponding elements. For example, the above expressions are not intended to limit the order or importance of the corresponding elements. The above expressions are used to distinguish one component from another.

[0131] The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. A singular expression includes a plural expression unless there is a significant difference in context or scheme between them.

[0132] The above description is merely an exemplary embodiment of the present invention and is not intended to limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the appended claims.

[0133] Those skilled in the art will understand that the various technical features of the above-described embodiments may be omitted, added, or combined in any manner accordingly. To make the description concise, not all possible combinations of the various technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, and simple transformation methods that can be thought of by those skilled in the art, as well as solutions for making adaptive and functional structural transformations of existing technologies, should be considered to be within the scope of this specification.

[0134] The embodiments described above merely represent several implementations of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patented invention. It should be noted that while the present invention has been shown and described with reference to various embodiments, it will be apparent to those skilled in the art that various variations and improvements in form and detail may be made without departing from the spirit of the present invention, and without departing from the scope of the present invention as defined by the appended claims, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patented invention shall be based on the appended claims.

Claims

1. A method for predicting single well production and recoverable reserves, characterized in that: include: Obtain production data of production wells and total injection volume of fracturing fluid, and pre-process the production data; Selecting a historical data time period for fitting, and determining the relationship between the cumulative production and the flowback rate at each moment based on the cumulative production and the flowback rate at each moment in the historical data time period; Selecting a time period of historical data for fitting, and determining a relationship between the flowback rate and time based on the flowback rate and time fitting in the time period of historical data; Setting an extended time, and determining the return rate at a future time after the extended time based on the determined relationship between the return rate and time; Determine the cumulative production at a future time after the extended time based on the flowback rate after the extended time and the relationship between the cumulative production at each time point and the flowback rate; Based on the extended time and the cumulative output at future times after the extended time, the daily output at future times is calculated.

2. The method for predicting single well production and recoverable reserves according to claim 1, characterized in that: The preprocessing of the production data includes: Determine the flowback rate at each moment based on the cumulative water production and the total injection volume of the fracturing fluid at each moment; Determine the time logarithm corresponding to each moment based on the accumulated production time at each moment; A backflow rate function at each moment is determined based on the backflow rate at each moment.

3. The method for predicting single well production and recoverable reserves according to claim 1, characterized in that: The method of fitting and determining the relationship between the cumulative production and the flowback rate at each moment in the historical data time period is based on the cumulative production and the flowback rate at each moment; comprises: Draw a scatter plot of the cumulative production and flowback rate at each moment in the historical data time period; Based on the scatter plot of the cumulative production at each moment and the flowback rate, a first fitting formula for characterizing the relationship between the cumulative production at each moment and the flowback rate is obtained by fitting.

4. The method for predicting single well production and recoverable reserves according to claim 1, characterized in that: The relationship between the flowback rate and time is determined based on the flowback rate of the historical data time stage and time fitting, including: Draw a scatter plot of the return rate and time during the historical data period; Based on the scatter plot of the backflow rate and time, a second fitting formula for characterizing the relationship between the backflow rate and time is obtained by fitting.

5. The method for predicting single well production and recoverable reserves according to claim 1, characterized in that: The method of determining the return flow rate at a future time after the extended time based on the determined relationship between the return flow rate and time comprises: Will extend the time t i Substitute into the second fitting formula to calculate the extension time t i The return rate at future times.

6. The method for predicting single well production and recoverable reserves according to claim 1, characterized in that: The method of determining the cumulative production at a future time after the extended time based on the flowback rate after the extended time and the relationship between the cumulative production at each time and the flowback rate that has been determined comprises: Substituting the backflow rate into the first fitting formula, the extended time t is obtained. i The cumulative output at future times.

7. A single well production and recoverable reserves prediction device, characterized in that: include: A preprocessing module is used to obtain the production data of the production well and the total injection volume of the fracturing fluid, and to preprocess the production data; A first fitting module is used to select a historical data time stage for fitting, and determine the relationship between the cumulative production and the flowback rate at each moment in the historical data time stage based on the cumulative production and the flowback rate at each moment in the historical data time stage; A second fitting module is used to select a time period of historical data for fitting, and determine the relationship between the flowback rate and time based on the flowback rate and time fitting of the time period of the historical data; A return rate calculation module, used to determine the return rate at a future time after the extended time based on the set extended time and the relationship between the determined return rate and time; A cumulative production calculation module, used to determine the cumulative production at a future time after the extended time based on the return flow rate after the extended time and the relationship between the cumulative production and the return flow rate at each time point that has been determined; The daily production calculation module is used to calculate the daily production at a future time based on the extended time and the cumulative production at a future time after the extended time.

8. A storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the single well production and recoverable reserves prediction method described in any one of claims 1 to 6 is implemented.

9. A terminal, characterized in that: include: Processor and memory; The memory is used to store computer programs; The processor is used to execute the computer program stored in the memory so that the terminal executes the single well production and recoverable reserves prediction method according to any one of claims 1 to 6.

Images