Shale gas single well gas production prediction method and device

Abstract

The application discloses a shale gas single-well gas production rate prediction method and device. The method comprises the following steps: acquiring the fracturing section length, original daily gas production rate and original pressure data of multiple shale gas wells in a target block; constructing a daily gas production rate reference curve and a pressure data reference curve based on the fracturing section length, original daily gas production rate and original pressure data; determining a shale gas well to be predicted in the target block, and determining the target predicted daily gas production rate of the shale gas well to be predicted based on the daily gas production rate reference curve and the pressure data reference curve. The problem of low geological reserve prediction accuracy of shale gas wells is solved, and the beneficial effect of improving the geological reserve prediction accuracy of shale gas wells is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of shale gas exploration and development, and particularly relates to a shale gas single-well gas production prediction method and device. BACKGROUND

[0002] At present, the future production scale and annual deployment well workload are usually predicted by combining conventional dynamic analysis methods and analogy methods for shale gas reservoirs. For the produced wells, the gas reservoir engineering theory and dynamic analysis procedures are usually used as the basis, and gas reservoir description, gas reservoir production dynamic analysis, gas reservoir engineering method calculation and productivity evaluation are integrated. In terms of gas well production prediction, the algorithms mainly include analytical model method, production decline method, material balance method and probability method, etc. The analogy method is usually used to predict the drilled but not produced and planned deployment wells. The shale gas reservoir production scale and annual deployment prediction involves the continuous update of multiple dimension data, including the continuous update of the production history data of the stage produced wells, the change of the drilled but not produced well properties to the drilled and fractured wells, and the change of the fractured well properties to the produced wells.

[0003] The existing shale gas reservoir production scale and annual deployment prediction method has the following limitations: (1) The production history of the gas reservoir produced wells is continuously updated in the prediction stage, and the workload of the production prediction method based on the conventional gas reservoir dynamic analysis is huge, and the prediction period is relatively long; (2) In the process of gas reservoir development, the properties of the drilled but not produced wells are continuously changed to the properties of the produced wells, and the number of the produced wells, the drilled wells, the drilled and completed wells and the fractured wells in the target block changes dynamically, which is difficult to adjust in real time and has a low production prediction accuracy; (3) The properties of the drilled but not produced wells are continuously changed to the properties of the drilled and completed wells or the fractured wells, and the horizontal section length and the fractured section length of the drilled and completed wells and the fractured wells need to be continuously updated, and the production of the drilled and completed wells and the fractured wells cannot be accurately predicted. SUMMARY

[0004] The present application provides a shale gas single-well gas production prediction method and device to solve the problem of low shale gas single-well gas production prediction accuracy.

[0005] According to an aspect of the present application, a shale gas single-well gas production prediction method is provided, which comprises:

[0006] obtaining the fractured section length, the original daily gas production and the original pressure data of a plurality of produced shale gas wells in a target block;

[0007] constructing a daily gas production reference curve and a pressure data reference curve based on the fractured section length, the original daily gas production and the original pressure data;

[0008] determining a shale gas well to be predicted in the target block, determining a target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve.

[0009] According to another aspect of the present application, there is provided a shale gas single well production prediction device, comprising:

[0010] a data acquisition module configured to acquire a fractured section length, an original daily gas production and an original pressure data of a plurality of shale gas wells in a target block;

[0011] a curve construction module configured to construct a daily gas production reference curve and a pressure data reference curve based on the fractured section length, the original daily gas production and the original pressure data respectively;

[0012] a production prediction module configured to determine a shale gas well to be predicted in the target block, and determine a target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve.

[0013] According to another aspect of the present application, there is provided an electronic device, comprising:

[0014] at least one processor; and

[0015] a memory connected with the at least one processor; wherein,

[0016] the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor to enable the at least one processor to execute the shale gas single well production prediction method according to any one of the embodiments of the present application.

[0017] According to another aspect of the present application, there is provided a computer readable storage medium storing computer instructions for enabling a processor to execute the shale gas single well production prediction method according to any one of the embodiments of the present application.

[0018] The technical scheme of the embodiment of the present application comprises the following steps: obtaining the fracturing section length, original daily gas production and original pressure data of multiple already-produced shale gas wells in a target block; accurately obtaining the associated data of the already-produced shale gas wells; then, constructing a daily gas production reference curve and a pressure data reference curve based on the fracturing section length, original daily gas production and original pressure data; the associated data of the already-produced shale gas wells can be used to accurately construct the daily gas production reference curve and the pressure data reference curve; finally, determining a shale gas well to be predicted in the target block, and determining the target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve, so as to solve the problem of low geological reserve prediction accuracy of shale gas wells and obtain the beneficial effect of improving the geological reserve prediction accuracy of shale gas wells.

[0019] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present application, nor is it used to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0021] Figure 1 is a flow chart of a shale gas single well production prediction method according to the first embodiment of the present application;

[0022] Figure 2a is a flow chart of a shale gas single well production prediction method according to the second embodiment of the present application;

[0023] Figure 2b is a flow chart of an optional example of a shale gas single well production prediction method according to the second embodiment of the present application;

[0024] Figure 2c is a sample schematic diagram of a daily gas production reference curve of an optional example of a shale gas single well production prediction method according to the second embodiment of the present application;

[0025] Figure 2d is a sample schematic diagram of a pressure data reference curve of an optional example of a shale gas single well production prediction method according to the second embodiment of the present application;

[0026] Figure 3 is a structural schematic diagram of a shale gas single well production prediction device according to the third embodiment of the present application;

[0027] Figure 4 is a structural schematic diagram of an electronic device for implementing a shale gas single well gas production prediction method according to an embodiment of the present application. DETAILED DESCRIPTION

[0028] In order for those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should fall within the scope of protection of the present application.

[0029] It should be noted that the terms "first", "second", and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0030] Embodiment one

[0031] Figure 1 A flowchart of a shale gas single well gas production prediction method is provided for the first embodiment of the present application. The present embodiment can be applicable to shale gas exploration and development. The method can be executed by a shale gas single well gas production prediction device. The shale gas single well gas production prediction device can be realized in the form of hardware and / or software. The shale gas single well gas production prediction device can be configured in an electronic device. As shown in the figure, the method comprises: Figure 1

[0032] S110, obtaining the length of the fractured section, the original daily gas production and the original pressure data of the multiple shale gas wells in the target block.

[0033] Wherein, shale gas can be understood as natural gas in a reservoir rock system mainly composed of organic matter-rich shale. The shale gas well that has been put into production can be understood as a shale gas well that has been put into production. The length of the fractured section can be understood as the length of the shale gas well that is fractured after the shale gas well is fractured. The daily gas production can be understood as the amount of shale gas produced by the shale gas well per day. It can be understood that the pressure data and the daily gas production have a correlation.​

[0034] Specifically, the single-well horizontal section length, the fracturing section length, the original daily gas production and the original pressure data of the multi-well shale gas well in the target block are acquired. The single-well horizontal section length and the fracturing section length are static data, and the original daily gas production and the original pressure data are dynamic data. The horizontal section length can be understood as the length of the horizontal section of the horizontal gas well, which can be the length from the point of drilling into the predetermined gas layer group and reaching the basic level of the well inclination to the depth of the completed well.

[0035] S120, constructing a daily gas production reference curve and a pressure data reference curve based on the fracturing section length, the original daily gas production and the original pressure data.

[0036] The daily gas production reference curve can be understood as a fitting curve in a unit fracturing section length daily gas production and production time coordinate system. The pressure data reference curve can be understood as a fitting curve in a casing pressure and production time coordinate system.

[0037] Specifically, the fracturing section length, the original daily gas production and the original pressure data are subjected to curve fitting and extrapolation to finally acquire the continuous and smooth unit fracturing section length daily gas production reference curve and the pressure data reference curve of the target block. It can be understood that the daily gas production reference curve contains the known original daily gas production and the predicted daily gas production; and the pressure data reference curve contains the known original pressure data and the predicted pressure data.

[0038] S130, determining the shale gas well to be predicted in the target block, and determining the target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve.

[0039] The shale gas well to be predicted is the shale gas well to be predicted in daily gas production. The target predicted daily gas production can be understood as the daily gas production of the predicted shale gas well at the target prediction time point.

[0040] Specifically, the shale gas well to be predicted in the target block can be determined by a preselected manner, and the daily gas production of the shale gas well to be predicted at the target prediction time point is determined based on the daily gas production reference curve and the pressure data reference curve. The preselected manner can be pre-set by experience, for example, manual selection or automatic selection by the system according to the type of the shale gas well, whether it is put into production or the production time, which is not limited in the embodiment.

[0041] Optionally, the target predicted daily gas production of the shale gas well to be predicted is determined based on the daily gas production reference curve and the pressure data reference curve, including: when the shale gas well to be predicted is the shale gas well that has been put into production, determining the first predicted time point and the production time corresponding to the shale gas well that has been put into production; when the production time reaches a preset production time threshold, determining the actual cumulative daily gas production corresponding to the production time, and determining the actual cumulative daily gas production corresponding to the production time based on the actual casing pressure data of the shale gas well that has been put into production. actual pressure drop-time integral; determine the reference cumulative daily gas production corresponding to the produced time and the first predicted daily gas production corresponding to the predicted time point based on the daily gas production reference curve, and determine the reference pressure drop-time integral corresponding to the produced time based on the pressure data reference curve; determine the second predicted daily gas production of the produced shale gas well at the first predicted time point based on the first predicted daily gas production, the actual cumulative daily gas production, the reference cumulative daily gas production, the actual pressure drop-time integral and the reference pressure drop-time integral.

[0042] The "existing production time" can be understood as the number of days of production. The preset production time threshold can be set based on experience, for example, 90 days, and this embodiment does not impose any restrictions thereon. The "actual cumulative daily gas production" can be understood as the sum of the daily gas production from the first day of a shale gas well's production to the current day. For example, if a shale gas well has been in production for 30 days, the "actual cumulative daily gas production" is the sum of the daily gas production for those 30 days. The "casing pressure" can be understood as the casing pressure, which is the residual pressure after the flow pressure lifts oil and gas from the bottom of the well through the annular space between the oil and casing to the wellhead. The "reference cumulative daily gas production" can be understood as the sum of all daily gas production within the "existing production time" on the daily gas production reference curve. The "first predicted daily gas production" can be understood as the daily gas production corresponding to a future predicted time point on the daily gas production reference curve. The "first predicted time point" can be understood as the time point at which the shale gas well's gas production is predicted within a future time range based on the current time point. The "second predicted daily gas production" can be understood as the potential daily gas production of the shale gas well at the first predicted time point.

[0043] For example, when the production time reaches a preset production time threshold, the sum of the daily gas production of the production days is determined as the actual cumulative daily gas production corresponding to the production days; the formula is as follows:

[0044]

[0045] Among them, Q i (n) is the cumulative gas production corresponding to the production time n of the i-th production well, in m 3 ;q i (t) is the daily gas production of the i-th well that has been put into production corresponding to the actual production time t;

[0046] The actual pressure drop-time integral corresponding to the produced time length of the shale gas well in production is determined according to the actual casing pressure data of the shale gas well in production, and is expressed by the following formula:

[0047] S i (n)=∫1 n P i (t)dt-∫1 n P i (n)dt

[0048] Wherein, S i (n) is the actual pressure drop-time integral corresponding to the produced time length n of the i th well in production, and the unit is MPa·d; P i (t) is the pressure corresponding to different produced time of the i th well, MPa; P i (n) is the average pressure level corresponding to the produced time length n of the i th well, and the unit is MPa.

[0049] It is worth mentioning that, since the pressure corresponding to the produced time length n of the well in production will have abnormal values due to shut-in or other measures, the data points are extended forward by a, and all data points (P i (n-a+1), P i (n-a+2), P i (n-a+1)…P i (n-2), P i (n-1), P i (n) are taken, and the average pressure level corresponding to the actual production time n is determined by the M50 statistical method. For example, if n is 100, the first 25 values and the last 25 values are deleted by the M50 statistical method, and only the remaining 50 middle values are retained for summation and average value operation. Wherein, a is the total number of data points extended forward, and the value range of a can be set according to experience, for example, 6-10, which is not limited in the embodiment.

[0050] Specifically, based on the daily gas production reference curve, the reference cumulative daily gas production corresponding to the produced time length and the first predicted daily gas production corresponding to the predicted time point on the daily gas production reference curve are determined; wherein, the calculation formula of the reference cumulative daily gas production corresponding to the produced time length is as follows:

[0051]

[0052] Wherein, Q s (n) is the reference cumulative daily gas production corresponding to the produced time length n; n is the produced time length; q s (t) is the unit fracturing section length daily gas production corresponding to the actual production time t of the well in production.

[0053] determining a reference pressure drop-time integral corresponding to the produced time length based on the pressure data reference curve, and the calculation formula of the reference pressure drop-time integral corresponding to the produced time length is as follows:

[0054] S D (n) = ∫1 n P D (n)dt n P D (n)dt

[0055] Wherein, S D (n) is the reference pressure drop-time integral corresponding to the pressure data when the production time is n, and the unit is MPa·d; P D (n) is the pressure value on the pressure data curve when the produced time length is n, and the unit is MPa.

[0056] Optionally, the product of the first predicted daily gas production, the first ratio of the actual cumulative daily gas production to the reference cumulative daily gas production, the second ratio of the actual pressure drop-time integral to the reference pressure drop-time integral, and the fracturing section length is taken as the second predicted daily gas production of the produced shale gas well at the predicted time point. The specific calculation formula is as follows:

[0057]

[0058] Wherein, q i (n+k) is the daily gas production corresponding to the predicted produced time n+k of the i th produced well; the unit is m 3 / d; k is the predicted time point in the future time range, k=(1, 2, 3…); q S (n+k) is the daily gas production corresponding to the produced time n+k in the daily gas production reference curve, and the unit is m 3 / (d·m); is the fracturing section length of the i th produced well.

[0059] Optionally, after determining the produced time length of the produced shale gas well based on the first predicted time point corresponding to the produced shale gas well, if the produced time length is shorter than the preset production time length threshold, the second predicted daily gas production of the produced shale gas well at the first predicted time point is determined based on the fracturing section length of the produced shale gas well and the first predicted daily gas production.

[0060] For example, if the preset production time length threshold is 90 days, when the produced time length is less than 90 days, the daily gas production of the shale gas well decreases rapidly and fluctuates greatly in the early production stage, and the future daily gas production can be directly predicted by using the fracturing section length of the produced well and the daily gas production reference curve of the unit fracturing section length, and the calculation formula is as follows:

[0061]

[0062] wherein, q i (n+k) is the predicted daily gas production of the shale gas well with the production time n less than 90 days, in units of m 3 (n+k) is the daily gas production corresponding to the production time n+k in the daily gas production reference curve, in units of m S (n+k) is the daily gas production corresponding to the production time n+k in the daily gas production reference curve, in units of m 3 / (d·m); is the fractured length of the i-th well with the production time n less than 90 days, in units of m.

[0063] Optionally, the method further comprises: in the case that the shale gas well to be predicted is a drilled but not yet produced shale gas well, determining a target well type corresponding to the drilled but not yet produced shale gas well and a second prediction time point corresponding to the drilled but not yet produced shale gas well, wherein the target well type is a drilling well, a completed well or a fractured well; determining a third predicted daily gas production of the drilled but not yet produced shale gas well at the second prediction time point based on the daily gas production reference curve; determining a single-well horizontal section length of the drilled but not yet produced shale gas well based on the target well type, and determining a cumulative fractured length and a cumulative horizontal section length of the produced shale gas well in the target block; and determining a fourth predicted daily gas production of the drilled but not yet produced shale gas well based on the third predicted daily gas production, the single-well horizontal section length, the cumulative fractured length and the cumulative horizontal section length.

[0064] The third predicted daily gas production can be understood as a predicted daily gas production of a drilling well, and the fourth predicted daily gas production can be understood as a predicted daily gas production of a completed well or a fractured well.

[0065] Specifically, in the case that the shale gas well to be predicted is a drilled but not yet produced shale gas well, a target well type to which the shale gas well to be predicted belongs is determined, and a predicted daily gas production of the shale gas well to be predicted is determined in different manners based on different target well types.

[0066] In the embodiments of the present application, in the case that the shale gas well to be predicted is a drilled but not yet produced shale gas well, a target well type corresponding to the shale gas well to be predicted is determined, and a predicted daily gas production of the shale gas well to be predicted is accurately calculated according to a corresponding calculation manner of the target well type, thereby improving the accuracy of the predicted daily gas production.

[0067] Optionally, the determining the single-well horizontal section length of the drilled but not put-into-production shale gas well based on the target well type comprises: in the case that the target well type is the drilling well, obtaining a preset horizontal section length of the drilling well as the single-well horizontal section length of the drilled but not put-into-production shale gas well; and in the case that the target well type is the drilled well or the fractured well, obtaining an actual drilled horizontal section length of the drilled well or the fractured well as the single-well horizontal section length of the drilled but not put-into-production shale gas well.

[0068] Specifically, in the case that the target well type is the drilling well, the actual length at the time of drilling completion cannot be accurately obtained because the gas well is still being drilled, and thus a preset drilling horizontal section length is taken as the single-well horizontal section length; in the case that the target well type is the drilled well or the fractured well, the actual drilled horizontal section length of the drilled well or the fractured well is obtained as the single-well horizontal section length of the drilled but not put-into-production shale gas well.

[0069] Exemplarily, the predicted daily gas production of the drilling well is determined based on a designed horizontal section length of the drilling well, a cumulative fractured section length of the put-into-production well and a cumulative horizontal section length of the put-into-production well in the target block. Assuming that there are j drilled but not put-into-production wells:

[0070]

[0071] wherein q Drilling (t) is the predicted daily gas production of the drilling well, in units of m 3 / d; is the unit fractured section length daily gas production corresponding to the actual production time t of the i-th put-into-production well; L LD is the designed horizontal section length of the drilling well; is the cumulative fractured section length of the put-into-production well in the target block, in units of m; is the cumulative horizontal section length of the put-into-production well in the target block, in units of m.

[0072] The drilled well and the fractured well utilize the actual drilled horizontal section length and the horizontal section length fractured utilization rate to predict the production:

[0073]

[0074] q rest (t) is the daily gas production of the drilled well or the fractured well, in units of m 3 / d; L LA is the actual drilled horizontal section length of the drilled well or the fractured well, in units of m. is the cumulative fractured section length of the put-into-production well in the target block, in units of m; is the cumulative horizontal section length of the put-into-production well in the target block, in units of m.

[0075] Optionally, the determining the target predicted daily gas production of the to-be-predicted shale gas well based on the daily gas production reference curve and the pressure data reference curve comprises: in the case that the to-be-predicted shale gas well is a planned deployment well, determining a fifth predicted daily gas production of the planned deployment well at a third predicted time point based on the daily gas production reference curve; determining a cumulative fracturing section length and a cumulative horizontal section length of all the produced shale gas wells in the target block, and determining an average horizontal section length corresponding to the planned deployment well based on an actual drilled horizontal section length of the produced shale gas well; determining a sixth predicted daily gas production of the planned deployment well based on the fifth predicted daily gas production, the average horizontal section length, the cumulative fracturing section length and the cumulative horizontal section length.

[0076] The sixth predicted daily gas production can be understood as a predicted daily gas production of a block deployment well.

[0077] For example, assuming that w wells need to be deployed in the next year in the block, the single-well production is predicted according to the average drilled horizontal section length and the average horizontal section length fracturing utilization rate of the block, and the specific calculation formula is as follows:

[0078]

[0079] The sixth predicted daily gas production of the planned deployment well is determined based on the fifth predicted daily gas production, the average horizontal section length, the cumulative fracturing section length and the cumulative horizontal section length. Deploy The sixth predicted daily gas production of the planned deployment well is determined based on the fifth predicted daily gas production, the average horizontal section length, the cumulative fracturing section length and the cumulative horizontal section length. 3 / d. The sixth predicted daily gas production of the planned deployment well is determined based on the fifth predicted daily gas production, the average horizontal section length, the cumulative fracturing section length and the cumulative horizontal section length. The sixth predicted daily gas production of the planned deployment well is determined based on the fifth predicted daily gas production, the average horizontal section length, the cumulative fracturing section length and the cumulative horizontal section length. The sixth predicted daily gas production of the planned deployment well is determined based on the fifth predicted daily gas production, the average horizontal section length, the cumulative fracturing section length and the cumulative horizontal section length.

[0080] The technical scheme of the embodiment of the present application obtains the fracturing section length, the original daily gas production and the original pressure data of a plurality of produced shale gas wells in a target block, accurately obtains the associated data of the produced shale gas well, then constructs a daily gas production reference curve and a pressure data reference curve based on the fracturing section length, the original daily gas production and the original pressure data, accurately constructs the daily gas production reference curve and the pressure data reference curve based on the associated data of the produced shale gas well, finally determines a to-be-predicted shale gas well in the target block, and determines the target predicted daily gas production of the to-be-predicted shale gas well based on the daily gas production reference curve and the pressure data reference curve, thereby solving the problem of low geological reserve prediction accuracy of a shale gas well and achieving the beneficial effect of improving the geological reserve prediction accuracy of the shale gas well.

[0081] Embodiment two

[0082] Figure 2aA flow chart of a method for predicting the gas production of a single shale gas well provided in Example 2 of the present invention is a further refinement of how to construct a daily gas production reference curve and a pressure data reference curve based on the fracturing section length, original daily gas production and original pressure data in this embodiment and the above embodiment. Optionally, the daily gas production reference curve and the pressure data reference curve are respectively constructed based on the fracturing section length, the original daily gas production and the original pressure data, including: determining the target daily gas production and target pressure data of the shale gas well in production based on the original daily gas production and the original pressure data corresponding to the shale gas well in production; determining the unit fracturing section daily gas production for each shale gas well in production based on the target daily gas production and the fracturing section length; determining the reference daily gas production corresponding to the production time point for each production time point based on at least part of the unit fracturing section daily gas production corresponding to multiple shale gas wells in production, and constructing a daily gas production reference curve based on the reference daily gas production corresponding to multiple production time points; determining the reference pressure data corresponding to the production time point based on at least part of the target pressure data corresponding to multiple shale gas wells in production, and constructing a pressure data reference curve based on the reference pressure data corresponding to multiple production time points.

[0083] like Figure 2a As shown, the method includes:

[0084] S210: Obtaining data on the length of the fracturing section, original daily gas production, and original pressure of multiple shale gas wells already in production in the target block.

[0085] S220. Determine the target daily gas production and target pressure data of the shale gas well that has been put into production based on the original daily gas production and the original pressure data corresponding to the shale gas well that has been put into production.

[0086] The target daily gas production can be understood as valid daily gas production data, and the target pressure data can be understood as valid pressure data.

[0087] Specifically, based on all original daily gas production and original pressure data corresponding to the shale gas wells that have been put into production, valid daily gas production data and valid pressure data are screened out.

[0088] Optionally, the target daily gas production and target pressure data of the shale gas well that has been put into production are determined based on the original daily gas production and the original pressure data corresponding to the shale gas well that has been put into production, including: taking the original daily gas production of the shale gas well that has been put into production as a benchmark, eliminating the data that is zero in the original daily gas production, and obtaining the target daily gas production of the shale gas well that has been put into production; eliminating the original pressure data corresponding to the eliminated original daily gas production, and obtaining the target pressure data of the shale gas well that has been put into production.

[0089] Specifically, taking the daily gas production data of the shale gas well as a benchmark, the data with zero daily gas production is removed to form the continuous daily gas production and pressure data of each shale gas well, and is sequentially sorted as the produced time, and the produced time is marked as 1, 2, 3, …, and the unit of the produced time is day.

[0090] In the embodiment of the present application, by removing the data with zero daily gas production, the data with zero daily gas production caused by well shut-in or other conditions is avoided, and the accuracy of the daily gas production prediction is improved.

[0091] S230, for each of the produced shale gas well, based on the target daily gas production and the length of the fracturing section, the daily gas production per unit length of the fracturing section is determined.

[0092] Specifically, based on the obtained continuous daily gas production data of each shale gas well and the specific length of the fracturing section, the daily gas production data corresponding to each well per unit length of the fracturing section is obtained. For example, assuming that the target block has produced m wells:

[0093]

[0094] wherein, is the daily gas production per unit length of the fracturing section corresponding to the actual production time t of the i-th produced well, m 3 (d·m); t is the actual production time after removing the data with zero daily gas production, d, t=(1, 2, 3, …); q i (t) is the daily gas production corresponding to the actual production time t of the i-th produced well, unit m 3 / d, t=(1, 2, 3, …); is the actual length of the fracturing section of the i-th produced well, m, i=(1, 2, 3, … m).

[0095] Optionally, the M50 statistical method is used to process the unit length of the fracturing section and the pressure data corresponding to each production time, and finally the reference daily gas production and reference pressure data corresponding to each production time point are obtained. The unit length of the fracturing section corresponding to the actual production time t is the M50 statistical value of all produced wells , the pressure corresponding to t is the M50 statistical value of all produced wells 1 (t), P 2 (t), P 3 (t) … P m-2 (t), P m-1 (t), P mM50 statistics value of the unit fracturing length reference daily gas production curve. The M50 statistics method is to sort all the unit fracturing length daily gas production and pressure data corresponding to each production time from large to small and to calculate the arithmetic mean value of the data in the interval of 25% to 75% as the unit fracturing length daily gas production and pressure corresponding to the production time. According to the above statistical process, the reference daily gas production and reference pressure data of the target area are finally obtained, and the reference daily gas production is expressed as q S (t) represents the daily gas production corresponding to the tth day of the unit fracturing length reference daily gas production curve, m 3 / (d·m). D (t) represents the pressure corresponding to the tth day of the pressure data reference curve, MPa.

[0096] S240, for each production time point, determining the reference daily gas production corresponding to the production time point based on at least part of the unit fracturing length daily gas production of the multiple wells, and constructing a daily gas production reference curve based on the reference daily gas production corresponding to multiple production time points.

[0097] Specifically, the actual unit fracturing length reference daily gas production is curve-fitted and extrapolated to finally obtain a continuous and smooth unit fracturing length reference daily gas production curve of the target block. The daily gas production of a shale gas well shows a short-time rise in the initial production stage, reaches a peak, and then rapidly enters a decline stage. The initial production rise stage is removed from the actual unit fracturing length reference daily gas production data of the target block, and the unit fracturing length peak daily gas production data is curve-fitted. The actual reference pressure data of the target block is curve-fitted. The unit fracturing length reference daily gas production fitting formula is:

[0098]

[0099] wherein q S (t) is the daily gas production corresponding to the tth day of the unit fracturing length reference daily gas production curve, m 3 / (d·m). C1, C2, C3, C4, and C5 are coefficients to be solved.

[0100] Specifically, the reference daily gas production corresponding to multiple production time points is substituted into the unit fracturing length reference daily gas production fitting formula to solve the value of t. Given q S (t) is the daily gas production corresponding to the tth day of the unit fracturing length reference daily gas production curve, m S (t) and the value of t, the q S (t) and the value of t of multiple production time points are substituted into the unit fracturing length reference daily gas production fitting formula to obtain the coefficient values of C1, C2, C3, C4, and C5.

[0101] S250, determining reference pressure data corresponding to the production time points based on at least part of the target pressure data corresponding to the plurality of the produced shale gas wells, and constructing a pressure data reference curve based on the reference pressure data corresponding to the plurality of the production time points.

[0102] Specifically, the actual reference pressure data is curve-fitted and extrapolated to obtain a continuous and smooth pressure data reference curve of the target block. The fitting formula of the pressure data reference curve is as follows:

[0103]

[0104] P (t) = C6 + C7t + C8t2 + C9t3 + C10t4 D P (t) is the pressure corresponding to the t time of the pressure data reference curve, and the unit is MPa.

[0105] C6, C7, C8, C9, C 10 are coefficients to be solved.

[0106] Specifically, the reference pressure data corresponding to the plurality of the production time points determined above is substituted into the fitting formula of the pressure data reference curve to obtain the value of t. P D (t) is the pressure corresponding to the t time of the pressure data reference curve, and P D (t) and the value of t are known, the P D (t) and the value of t of the plurality of the production time points are substituted into the unit fracture length reference daily gas production fitting formula to obtain the coefficient values of C6, C7, C8, C9, C 10 .

[0107] In the fitting process of the daily gas production reference curve and the pressure data reference curve, the fitting precision control parameters are the determination coefficient and the adjusted determination coefficient, and the control conditions are R 2 > 0.9 and R 2 (Adj) > 0.9, and interpolation processing is performed when the fitting precision meets the control conditions.

[0108] The determination coefficient calculation formula is as follows:

[0109]

[0110] y is the actual observed daily gas production value; is the regression predicted daily gas production value, is the average value of all actual observation values.

[0111] The adjusted determination coefficient calculation formula is as follows:

[0112]

[0113] Wherein, k is the number of data points in the data set, and p is the number of independent variables (including constant term) in the regression equation. After the fitting accuracy meets the above conditions, the unit fracturing length daily gas production reference curve and the pressure data reference curve are extrapolated for iterative production prediction.

[0114] S260, determining the shale gas well to be predicted in the target block, determining the target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve.

[0115] Optionally, the method further comprises: acquiring the shale gas well to be counted in the target block, wherein the shale gas well to be counted comprises the shale gas well that has been put into production, the shale gas well that has been drilled but not put into production, and the planned deployment well; determining the average production time rate corresponding to the target block based on the historical production time of the shale gas well that has been put into production, wherein the average production time rate is associated with the natural time and the actual production time; for each of the shale gas well to be counted, determining the target predicted production time period corresponding to the shale gas well to be counted based on the preset production prediction time, the average production time rate, and the production date corresponding to the shale gas well to be counted; determining the single-well predicted production of each of the shale gas well to be counted in the corresponding target predicted production time period, and determining the target block production of the target block at the production prediction time based on the single-well predicted production corresponding to all the shale gas well to be counted in the target block.

[0116] Specifically, if the shale gas well to be counted comprises the shale gas well that has been put into production, the single-well predicted future production is continuous production data, and the predicted production needs to be batched to the natural year according to the average production time rate of the target block. Given the remaining effective production time of the shale gas well that has been put into production in the current year, which is the product of the natural production time in the current year and the average production time rate of the target block minus the actual effective production time in the current year, and the actual production time in the subsequent years is the product of the average production time rate and the natural year time. If the shale gas well to be counted comprises the drilled but not produced well, the predicted production is superimposed, and each drilled but not produced well is assigned a production date according to the drilling date and the average well construction period (the period from drilling to production of shale gas well) of the average actual production well in the target block. If the shale gas well to be counted comprises the planned deployment well, it is evenly distributed to the beginning of each month in the next year, and the predicted production of each planned deployment well is distributed to a specified production date according to the assigned drilling date and the average well construction period of the target block. The target block production scale is composed of three parts, including the predicted production of the shale gas well that has been put into production, the predicted production of the drilled but not produced well (positive drilling well and fracturing well), and the predicted production of the planned deployment well. The target block production scale production prediction profile can be automatically adjusted according to the number of future deployment wells, and timely provide basis for shale gas reservoir future production capacity construction deployment and long-term planning.

[0117] The embodiment of the present application can accurately determine the effective data in the original data by determining the target daily gas production and target pressure data of the produced shale gas well based on the original daily gas production and the original pressure data corresponding to the produced shale gas well; then, for each of the produced shale gas well, the unit fracturing section daily gas production is determined based on the target daily gas production and the fracturing section length; the unit fracturing section daily gas production corresponding to the produced shale gas well is accurately determined based on the effective data; then, for each production time point, the reference daily gas production corresponding to the production time point is determined based on at least part of the unit fracturing section daily gas production corresponding to the plurality of produced shale gas wells, and the reference daily gas production reference curve is constructed based on the reference daily gas production corresponding to the plurality of production time points; the reference curve of the daily gas production containing the reference daily gas production corresponding to the plurality of time points is constructed; finally, the reference pressure data corresponding to the production time point is determined based on at least part of the target pressure data corresponding to the plurality of produced shale gas wells, and the pressure data reference curve is constructed based on the reference pressure data corresponding to the plurality of production time points. The more accurate daily gas production reference curve and pressure data reference curve are determined, which provides a reference basis for the subsequent accurate prediction of the daily gas production, and improves the accuracy of the daily gas production prediction.

[0118] Figure 2b A flowchart of an optional example of a shale gas single well gas production prediction method is provided. As shown in Figure 2b , the shale gas single well gas production prediction method can specifically include the following steps:

[0119] (1) Basic data preparation

[0120] ① Production data preparation: obtain static data such as single well horizontal section length and fracturing section length of the produced shale gas well in the target block, and dynamic data such as daily gas production and pressure;

[0121] ② Basic data processing: taking the shale gas well daily gas production data as the benchmark, the daily gas production of zero (shut-in) data is removed to form the continuous daily gas production and pressure data of each shale gas well, and is sequentially sorted and marked as the produced time length, which is marked as 1, 2, 3……, unit: day;

[0122] ③ Unit gas production calculation: the continuous daily gas production data and the specific fracturing section length of each shale gas well obtained in step ② are used to calculate the unit fracturing section length daily gas production data of each well, assuming that there are m wells in the target block:

[0123]

[0124] wherein, is the unit fracturing section length daily gas production corresponding to the actual production time t of the i th produced well, m 3(m3 / d); t is the produced time length after removing the data of zero daily gas production, d, t = (1, 2, 3…); q i (t) is the daily gas production corresponding to the actual production time t of the i th well, unit: m 3 / d, t = (1, 2, 3…); is the actual fracturing length of the i th well, m, i = (1, 2, 3…m).

[0125] ④Unit data processing: using M50 statistical method to process the unit fracturing length daily gas production and pressure data corresponding to each production time, finally obtaining the reference daily gas production and reference pressure data corresponding to each production time point. The unit fracturing length daily gas production corresponding to the actual production time t is the M50 statistical value of all the wells (P 1 (t), P 2 (t), P 3 (t)…P m-2 (t), P m-1 (t), P m (t)). M50 statistical method is to sort all the unit fracturing length daily gas production and pressure data corresponding to each production time from large to small and take the arithmetic mean value of the 25% to 75% interval data as the unit fracturing length daily gas production and pressure corresponding to the production time. According to the above statistical process, the reference daily gas production and reference pressure data of the target area are finally obtained, and q S (t) represents the unit fracturing length reference gas production curve corresponding to the daily gas production of the t th day, m 3 / (d·m); P D (t) represents the pressure data reference curve t time corresponding pressure, MPa.

[0126] ⑤Unit fracturing length daily gas production reference curve and pressure data reference curve data fitting

[0127] Figure 2c A sample schematic diagram of the daily gas production reference curve of an optional example of a shale gas single well gas production prediction method is provided. As Figure 2cAs shown, the actual unit fracturing section length reference daily gas production data obtained is curve fitted and extrapolated, and finally a continuous and smooth unit fracturing section length reference gas production curve is obtained for the target block. The daily gas production of shale gas wells shows a short-term increase in the initial production period, and then quickly enters a decreasing stage after reaching the peak. For the target block unit fracturing section length reference daily gas production data that has been obtained, the initial production increase stage is eliminated, and the unit fracturing section length peak daily gas production data is curve fitted. Curve fitting is performed on the actual target block reference pressure data. The fitting formula for the unit fracturing section length reference daily gas production is:

[0128]

[0129] Among them, q S (t) is the daily gas production per unit fracturing section length in the reference curve of daily gas production on the tth day, in m 3 / (d·m). C1, C2, C3, C4, and C5 are the coefficients to be solved.

[0130] The value of t is obtained by substituting the reference daily gas production corresponding to the multiple production time points determined above into the fitting formula of the reference daily gas production per unit fracturing stage length. S (t) is the reference daily gas production per unit fracturing section length. The daily gas production on the production curve corresponds to the daily gas production on day t. s (t) and t value, q s Substituting (t) and t values ​​into the fitting formula of reference daily gas production per unit fracturing section length can obtain the coefficient values ​​of C1, C2, C3, C4, and C5.

[0131] Figure 2d A sample diagram of a pressure data reference curve for an optional example of a method for predicting gas production of a single shale gas well is provided. Figure 2d As shown in the figure, the actual reference pressure data obtained is subjected to curve fitting and extrapolation, and finally a continuous and smooth pressure data reference curve of the target block is obtained. The pressure data reference curve fitting formula is:

[0132]

[0133] Among them, P D (t) is the pressure corresponding to time t of the pressure data reference curve, in MPa.

[0134] C6, C7, C8, C9, C 10 are the coefficients to be solved.

[0135] Specifically, the reference pressure data corresponding to the multiple production time points determined above are substituted into the pressure data reference curve fitting formula to obtain the value of t. D(t) is the pressure corresponding to the time t of the pressure data reference curve, and P D On the basis of P D (t) and t, the values of C6, C7, C8, C9, C 10 can be obtained by substituting them into the reference daily gas production fitting formula of unit fracturing section length.

[0136] In the fitting process of the daily gas production curve and the pressure data reference curve, the fitting accuracy control parameters are the determination coefficient and the adjusted determination coefficient, and the control conditions are R 2 > 0.9 and R 2 (Adj) > 0.9, and interpolation processing is performed when the fitting accuracy meets the control conditions.

[0137] The determination coefficient calculation formula is as follows:

[0138]

[0139] Wherein, y is the actual observed daily gas production value; is the regression predicted daily gas production value, is the average value of all actual observation values.

[0140] The adjusted determination coefficient calculation formula is as follows:

[0141]

[0142] Wherein, k is the number of data points in the data set, and p is the number of independent variables (including constant term) in the regression equation. After the fitting accuracy meets the above conditions, the unit fracturing section length reference daily gas production curve and the pressure data reference curve are extrapolated for yield iterative prediction.

[0143] 6. Actual cumulative gas production of the well in production and pressure drop-time integral

[0144] Suppose the actual production time of the well in production is n,

[0145]

[0146] Wherein, Q i (n) is the cumulative gas production corresponding to the actual production time n of the i th well in production, with the unit of m 3 ; q i (t) is the daily gas production corresponding to the actual production time t of the i th well in production;

[0147] According to the actual casing pressure data of the produced shale gas well, the actual pressure drop-time integral corresponding to the production time is determined, which is expressed by the formula as follows:

[0148] S i (n) = ∫1n P i (t)dt-∫1 n P i (n)dt

[0149] Wherein, S i (n) is the actual pressure drop-time integral corresponding to the production time n of the i-th well, with the unit of MPa·d; P i (t) is the pressure corresponding to different production time of the i-th well, MPa; P i (n) is the average pressure level corresponding to the production time n of the i-th well, with the unit of MPa.

[0150] It is worth mentioning that, since the pressure corresponding to the production time n of the i-th well will have abnormal values due to shut-in or other measures, the data points are extended forward by a, and all data points (P i (n-a+1), P i (n-a+2), P i (n-a+1)…P i (n-2), P i (n-1), P i (n) are taken, and the average pressure level corresponding to the actual production time n is determined by the M50 statistical method. For example, if n is 100, the first 25 values and the last 25 values are deleted by the M50 statistical method, and only the remaining 50 middle values are retained for summation and average operation. Wherein, a is the total number of data points extended forward, and the value range of a can be set according to experience, for example, 6-10, which is not limited in the embodiment.

[0151] (2) Production prediction of the i-th well

[0152] ① The production time n of the i-th well is obtained, and the reference cumulative daily gas production per unit fracturing section length and the reference pressure drop-time integral corresponding to the reference daily gas production per unit fracturing section length and the reference pressure data are obtained:

[0153] The reference cumulative daily gas production corresponding to the production time n is calculated according to the following formula:

[0154]

[0155] Wherein, Q s (n) is the reference cumulative daily gas production corresponding to the production time n; n is the production time; q s (t) is the daily gas production per unit fracturing section length corresponding to the actual production time t of the i-th well.

[0156] determine a reference pressure drop-time integral corresponding to the produced time length based on the pressure data reference curve, and the calculation formula of the reference pressure drop-time integral corresponding to the produced time length is as follows:

[0157] S D (n)=∫1 n P D (t)dt-∫1 n P D (n)dt

[0158] Wherein, S D (n) is the reference pressure drop-time integral corresponding to the pressure data when the production time is n, and the unit is MPa·d; P D (n) is the pressure value on the pressure data curve when the produced time length is n, and the unit is MPa.

[0159] ②The product of the first predicted daily gas production, the first ratio of the actual cumulative daily gas production to the reference cumulative daily gas production, the second ratio of the actual pressure drop-time integral to the reference pressure drop-time integral, and the fracturing section length is taken as the second predicted daily gas production of the produced shale gas well at the predicted time point. For example, according to all the production history data corresponding to the produced time length n, the future daily gas production of the produced well whose actual production time satisfies n≥90d (days) is predicted:

[0160]

[0161] Wherein, q i (n+k) is the daily gas production corresponding to the predicted produced time n+k of the ith produced well; the unit is m 3 / d; k is the predicted time point in the future time range, k=(1, 2, 3…); q S (n+k) is the daily gas production corresponding to the produced time n+k in the daily gas production reference curve, and the unit is m 3 / (d·m); is the fracturing section length of the ith produced well.

[0162] ③In the case where the produced time length is shorter than the preset production time length threshold, the second predicted daily gas production of the produced shale gas well at the first predicted time point is determined based on the fracturing section length of the produced shale gas well and the first predicted daily gas production. For example, for the produced well whose actual production time n<90d (days), the daily gas production decreases rapidly and fluctuates greatly at the initial stage of the gas well production, and the future daily gas production can be directly predicted by using the fracturing section length of the produced well and the daily gas production reference curve of the unit fracturing section length, and the calculation formula is as follows:

[0163]

[0164] wherein q i (n+k) is the predicted daily gas production of the shale gas well with the production time n less than 90 days, in unit of m 3 / d; q S (n+k) is the daily gas production corresponding to the production time n+k in the daily gas production reference curve, in unit of m 3 / (d·m); is the fractured length of the i-th well with the production time n less than 90 days, in unit of m.

[0165] (2) Production prediction of drilled but not yet put into production wells

[0166] In the actual shale gas reservoir development process, drilled but not yet put into production wells include drilling wells, completed wells and fractured wells. The drilling wells directly use the unit fractured length reference daily gas production to fit and extrapolate data, design the horizontal length and the product of the block average horizontal length utilization rate to predict the daily production. Assuming that there are j drilled but not yet put into production wells:

[0167]

[0168] wherein q Drilling (t) is the predicted daily gas production of the drilling well, in unit of m 3 / d; is the unit fractured length daily gas production corresponding to the actual production time t of the i-th well; L LD is the designed horizontal length of the drilling well; is the cumulative fractured length of the wells put into production in the target block, in unit of m; is the cumulative horizontal length of the wells put into production in the target block, in unit of m.

[0169] The completed wells and the fractured wells use the actual completed horizontal length and the horizontal length utilization rate to predict the production:

[0170]

[0171] q rest (t) is the daily gas production of the completed well and the fractured well, in unit of m 3 / d; L LA is the actual completed horizontal length of the completed well or the fractured well, in unit of m. is the cumulative fractured length of the wells put into production in the target block, in unit of m; is the cumulative horizontal length of the wells put into production in the target block, in unit of m.

[0172] (3) Production prediction of planned deployment wells

[0173] For example, assuming that the block needs to deploy w wells next year, the single well production is predicted according to the average completed horizontal section length and average horizontal section length fracturing utilization rate of the block, and the specific calculation formula is as follows:

[0174]

[0175] Wherein, q Deploy (t) is the predicted daily gas production of the planned deployment well, with the unit of m 3 / d; is the actual production time t corresponding to the unit fracturing section length daily gas production of the ith well that has been put into production; w is the number of planned deployment wells; is the cumulative horizontal section length of the well that has been put into production in the target block, with the unit of m; is the cumulative fracturing section length of the well that has been put into production in the target block, with the unit of m.

[0176] (4) Yield superposition of the target block

[0177] ① The predicted daily gas production of the well that has been put into production is superimposed, and the single well predicted future production is the continuous production data, which needs to be batched to the natural year according to the average production rate of the target block. The remaining effective production time of the well that has been put into production in the current year is given as the product of the natural production time in the current year and the average production rate of the target block minus the actual effective production time in the current year, and the actual production time in the subsequent years is the product of the average production rate and the natural year time.

[0178] ② The predicted production of the drilled but not yet put into production well is superimposed, and each drilled but not yet put into production well is distributed according to the drilling date and the average well construction period of the average actual put-into-production well in the target block (the shale gas well from drilling to production cycle);

[0179] ③ The predicted production of the planned deployment well is distributed to the beginning of each month next year, and the predicted production of each planned deployment well is distributed to the specified production date according to the assigned drilling date and the average well construction period of the target block;

[0180] ④ The yield scale of the target block is composed of three parts, including the predicted production of the well that has been put into production, the predicted production of the drilled but not yet put into production well (drilling well and fracturing well), and the predicted production of the planned deployment well. The yield prediction profile of the target block can be automatically adjusted according to the number of future deployment wells, so as to provide basis for the future production capacity construction and deployment of shale gas reservoir and long-term planning.

[0181] The embodiment of the present application predicts the future production of the drilled but not yet put into production well and the planned and deployed well through the learning and iteration of the production data of the target block well that has been put into production, superimposes the future production scale according to the production timeliness and the well construction cycle, dynamically predicts the overall production scale and the workload of the planned and deployed well. The dynamic real-time prediction of the shale gas reservoir production scale and the annual workload of the planned and deployed well is realized by comprehensively considering the production history data update and the dynamic change of the number of wells with different properties, the future production scale can be predicted in time according to the workload of the planned and deployed well, and the accuracy of the reserve prediction is improved.

[0182] Embodiment three

[0183] Figure 3 A shale gas single well gas production prediction device provided by the third embodiment of the present application is shown in a structural schematic diagram. Figure 3 As shown in the figure, the device comprises a data acquisition module 310, a curve construction module 320 and a gas production prediction module 330.

[0184] The data acquisition module 310 is used to acquire the fracturing section length, the original daily gas production and the original pressure data of the target block well that has been put into production; the curve construction module 320 is used to construct the daily gas production reference curve and the pressure data reference curve based on the fracturing section length, the original daily gas production and the original pressure data; and the gas production prediction module 330 is used to determine the shale gas well to be predicted in the target block, and determine the target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve.

[0185] The technical scheme of the embodiment of the present application acquires the fracturing section length, the original daily gas production and the original pressure data of the target block well that has been put into production through the data acquisition module; accurately acquires the associated data of the shale gas well that has been put into production; then, constructs the daily gas production reference curve and the pressure data reference curve based on the fracturing section length, the original daily gas production and the original pressure data through the curve construction module; accurately constructs the daily gas production reference curve and the pressure data reference curve based on the associated data of the shale gas well that has been put into production; finally, determines the shale gas well to be predicted in the target block through the gas production prediction module, and determines the target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve, thereby solving the problem of low geological reserve prediction accuracy of the shale gas well, and achieving the beneficial effect of improving the geological reserve prediction accuracy of the shale gas well.

[0186] Optionally, the curve construction module comprises:

[0187] A target gas amount and pressure acquisition unit is used to determine the target daily gas production and the target pressure data of the shale gas well that has been put into production based on the original daily gas production and the original pressure data corresponding to the shale gas well that has been put into production.

[0188] unit fracture section daily gas production acquisition unit, configured to determine, for each of the produced shale gas well, a unit fracture section daily gas production based on the target daily gas production and the fracture section length;

[0189] daily gas production reference curve construction unit, configured to determine, for each of the production time points, a reference daily gas production corresponding to the production time point based on at least part of the unit fracture section daily gas production corresponding to a plurality of the produced shale gas wells, and construct a daily gas production reference curve based on the reference daily gas production corresponding to a plurality of the production time points;

[0190] pressure data reference curve construction unit, configured to determine, for each of the production time points, a reference pressure data corresponding to the production time point based on at least part of the target pressure data corresponding to a plurality of the produced shale gas wells, and construct a pressure data reference curve based on the reference pressure data corresponding to a plurality of the production time points.

[0191] Optionally, the target gas production and pressure acquisition unit comprises:

[0192] target daily gas production acquisition sub-unit, configured to take the original daily gas production of the produced shale gas well as a benchmark, eliminate data of zero in the original daily gas production, and obtain a target daily gas production of the produced shale gas well;

[0193] target pressure data acquisition sub-unit, configured to eliminate original pressure data corresponding to the eliminated original daily gas production, and obtain a target pressure data of the produced shale gas well.

[0194] Optionally, the gas production prediction module comprises:

[0195] produced duration determination unit, configured to, in a case where the to-be-predicted shale gas well is the produced shale gas well, determine a produced duration of the produced shale gas well based on a first prediction time point corresponding to the produced shale gas well;

[0196] actual pressure drop-time integral determination unit, configured to, in a case where the produced duration reaches a preset production duration threshold, determine an actual cumulative daily gas production corresponding to the produced duration, and determine an actual pressure drop-time integral corresponding to the produced duration according to actual casing pressure data of the produced shale gas well;

[0197] reference pressure drop-time integral determination unit, configured to determine a reference cumulative daily gas production corresponding to the produced duration and a first prediction daily gas production corresponding to the prediction time point based on the daily gas production reference curve, and determine a reference pressure drop-time integral corresponding to the produced duration based on the pressure data reference curve;

[0198] The second predicted daily gas production determination unit is configured to determine a second predicted daily gas production of the shale gas well at a first predicted time point based on the first predicted daily gas production, the actual cumulative daily gas production, the reference cumulative daily gas production, the actual pressure drop-time integral, and the reference pressure drop-time integral.

[0199] Optionally, the device further comprises a second gas production prediction module.

[0200] The second gas production prediction module is configured to, after determining the produced duration of the shale gas well at the first predicted time point, determine a second predicted daily gas production of the shale gas well at the first predicted time point based on the fractured length of the shale gas well and the first predicted daily gas production when the produced duration is shorter than a preset production duration threshold.

[0201] Optionally, the gas production prediction module comprises:

[0202] The information determination unit is configured to, when the shale gas well to be predicted is a drilled but not yet produced shale gas well, determine a target well type corresponding to the drilled but not yet produced shale gas well and a second predicted time point corresponding to the drilled but not yet produced shale gas well, wherein the target well type is a drilling well, a completed well, or a fractured well.

[0203] The third predicted daily gas production determination unit is configured to determine a third predicted daily gas production of the drilled but not yet produced shale gas well at a second predicted time point based on the daily gas production reference curve.

[0204] The cumulative length determination unit is configured to determine a single-well horizontal length of the drilled but not yet produced shale gas well based on the target well type, and determine a cumulative fractured length and a cumulative horizontal length of the shale gas well in the target block.

[0205] The fourth predicted daily gas production determination unit is configured to determine a fourth predicted daily gas production of the drilled but not yet produced shale gas well based on the third predicted daily gas production, the single-well horizontal length, the cumulative fractured length, and the cumulative horizontal length.

[0206] Optionally, the third information determination unit comprises:

[0207] The first single-well horizontal length acquisition subunit is configured to, when the target well type is the drilling well, acquire a preset horizontal length of the drilling well as the single-well horizontal length of the drilled but not yet produced shale gas well.

[0208] The second single-well horizontal section length obtaining sub-unit is configured to, in a case where the target well type is the drilled well or the fractured well, obtain an actual drilled horizontal section length of the drilled well or the fractured well as the single-well horizontal section length of the drilled but not put-into-production shale gas well.

[0209] Optionally, the gas production amount prediction module comprises:

[0210] The fifth predicted daily gas production amount determining unit is configured to, in a case where the shale gas well to be predicted is a planned deployment well, determine a fifth predicted daily gas production amount of the planned deployment well at a third predicted time point based on the daily gas production amount reference curve.

[0211] The average horizontal section length determining unit is configured to determine a cumulative fractured section length and a cumulative horizontal section length of all the put-into-production shale gas wells in the target block, and determine an average horizontal section length corresponding to the planned deployment well based on the actual drilled horizontal section length of the put-into-production shale gas well.

[0212] The sixth predicted daily gas production amount determining unit is configured to determine a sixth predicted daily gas production amount of the planned deployment well based on the fifth predicted daily gas production amount, the average horizontal section length, the cumulative fractured section length and the cumulative horizontal section length.

[0213] The device further comprises a shale gas well to be counted obtaining module, an average production time rate obtaining module, a target predicted time period determining module and a target block production amount determining module.

[0214] The shale gas well to be counted obtaining module is configured to obtain shale gas wells to be counted in the target block, wherein the shale gas wells to be counted comprise the put-into-production shale gas well, the drilled but not put-into-production shale gas well and the planned deployment well.

[0215] The average production time rate obtaining module is configured to determine an average production time rate corresponding to the target block based on historical production time of the put-into-production shale gas well, wherein the average production time rate is associated with a natural time and an actual production time.

[0216] The target predicted time period determining module is configured to, for each of the shale gas wells to be counted, determine a target predicted time period corresponding to the shale gas well to be counted based on a preset production amount prediction time, the average production time rate and a put-into-production date corresponding to the shale gas well to be counted.

[0217] The target block production amount determining module is configured to respectively determine a single-well predicted production amount of each of the shale gas wells to be counted in a corresponding target predicted time period of the shale gas well to be counted, and determine a target block production amount of the target block at the production amount prediction time based on the single-well predicted production amounts corresponding to all the shale gas wells to be counted in the target block.

[0218] The shale gas single well gas production prediction device provided by the embodiment of the present application can execute the shale gas single well gas production prediction method provided by any of the embodiments of the present application, and has the function modules and beneficial effects corresponding to the execution method.

[0219] Embodiment Four

[0220] Figure 4 A structural schematic diagram of an electronic device 10 that can be used to implement embodiments of the present application is shown. The electronic device is intended to represent various forms of digital computers, such as laptops, desktops, tablets, personal digital assistants, servers, blade servers, mainframes, and other appropriate computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular telephones, smart phones, wearable devices (e.g., headsets, glasses, watches, etc.), and other similar computing devices. The components shown here, their connections and relationships, and their functions, are meant to be examples only, and are not intended to limit the implementations of the present application described and / or claimed in this document.

[0221] As shown in Figure 4 The electronic device 10 includes at least one processor 11, and a memory, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., which is communicatively connected to the at least one processor 11, wherein the memory stores a computer program that can be executed by the at least one processor. The processor 11 can execute various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0222] A plurality of components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, a loudspeaker, etc.; a storage unit 18, such as a magnetic disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network, such as the Internet, and / or various telecommunication networks.

[0223] The processor 11 can be various general and / or special purpose processing components having processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various specialized artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The processor 11 performs various methods and processes described above, such as the method of shale gas single well gas production prediction.

[0224] In some embodiments, the method of shale gas single well gas production prediction can be implemented as a computer program tangibly embodied in a computer readable storage medium, such as the storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed onto the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded onto the RAM 13 and executed by the processor 11, one or more steps of the method of shale gas single well gas production prediction described above can be performed. Alternatively, in other embodiments, the processor 11 can be configured to perform the method of shale gas single well gas production prediction by any other suitable means, such as by means of firmware.

[0225] Various implementations of the systems and techniques described above can be realized in digital electronic circuitry, integrated circuitry, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on a chip (SOC), a programmable logic device (PLD), a computer hardware, firmware, software, and / or combinations thereof. These various implementations can include implementation in one or more computer programs that are executable and / or interpretable on a programmable system including at least one programmable processor, which can be special or general purpose, coupled to receive data and instructions from, and to transmit data and instructions to, a storage system, at least one input device, and at least one output device.

[0226] Computer programs used to implement the methods of the application can be written in any combination of one or more programming languages. These computer programs can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the computer program, when executed by the processor of the machine, implements the functions / acts specified in the flowcharts and / or block diagrams. The computer program can be executed entirely on a machine, partially on a machine, partially on a machine as a stand-alone software package, partially on a machine and partially on a remote machine or entirely on a remote machine or server.

[0227] In the context of the present application, a computer-readable storage medium can be a tangible medium that can contain or store a computer program for use by or in connection with an instruction execution system, apparatus, or device. A computer-readable storage medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium can be a machine-readable signal medium. More specific examples of a machine-readable storage medium will include one or more lines of a program of instructions in a transitory signal, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0228] To provide for interaction with a user, the systems and techniques described here can be implemented on an electronic device having a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user and a keyboard and a pointing device (e.g., a mouse or a trackball) by which the user can provide input to the electronic device. Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form, including acoustic, speech, or tactile input.

[0229] The systems and techniques described here can be implemented in a computing system that includes a back end component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front end component (e.g., a user computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such back end, middleware, or front end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0230] The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system, to solve the defects of large management difficulty and weak business scalability in traditional physical host and VPS service.

[0231] It should be understood that the various forms of flow shown above can be reordered, added to, or have steps deleted. For example, the steps described in the present application can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions of the present application can be achieved, which are not limited herein.

[0232] The above detailed description does not constitute a limitation on the protection scope of the present application. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for predicting the gas production of a single shale gas well, characterized in that: include: Obtain the fracturing section length, original daily gas production, and original pressure data of multiple shale gas wells already in production in the target block; Constructing a daily gas production reference curve and a pressure data reference curve based on the fracturing section length, the original daily gas production and the original pressure data respectively; Determining a shale gas well to be predicted in the target block, and determining a target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve; The constructing of a daily gas production reference curve and a pressure data reference curve based on the fracturing section length, the original daily gas production and the original pressure data respectively includes: Determining target daily gas production and target pressure data of the shale gas well in production based on the original daily gas production and the original pressure data corresponding to the shale gas well in production; For each of the shale gas wells that have been put into production, determining a daily gas production per unit fracturing stage based on the target daily gas production and the length of the fracturing stage; For each production time point, determining a reference daily gas production corresponding to the production time point based on the daily gas production of at least a portion of the unit fracturing stages corresponding to the plurality of shale gas wells that have been put into production, and constructing a daily gas production reference curve based on the reference daily gas productions corresponding to the plurality of production time points; determining reference pressure data corresponding to the production time point based on at least part of the target pressure data corresponding to the plurality of shale gas wells that have been put into production, and constructing a pressure data reference curve based on the reference pressure data corresponding to the plurality of production time points; The determining of the target daily gas production and target pressure data of the shale gas well in production based on the original daily gas production and the original pressure data corresponding to the shale gas well in production includes: Taking the original daily gas production of the shale gas well in production as a benchmark, eliminating zero data in the original daily gas production to obtain the target daily gas production of the shale gas well in production; The original pressure data corresponding to the original daily gas production is eliminated to obtain the target pressure data of the shale gas well that has been put into production.

2. The method according to claim 1, characterized in that The determining the target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve includes: In a case where the shale gas well to be predicted is the shale gas well that has been put into production, determining a first prediction time point and an already produced time duration corresponding to the shale gas well that has been put into production; When the production time reaches a preset production time threshold, determining the actual cumulative daily gas production corresponding to the production time, and determining the actual pressure drop-time integral corresponding to the production time based on the actual casing pressure data of the shale gas well in production; determining a reference accumulated daily gas production corresponding to the production duration and a first predicted daily gas production corresponding to a predicted time point based on the daily gas production reference curve, and determining a reference pressure drop-time integral corresponding to the production duration based on the pressure data reference curve; The second predicted daily gas production of the put into production shale gas well at the first predicted time point is determined based on the first predicted daily gas production, the actual cumulative daily gas production, the reference cumulative daily gas production, the actual pressure drop-time integral and the reference pressure drop-time integral.

3. The method according to claim 2, characterized in that After determining the production time of the shale gas well in production based on the first predicted time point corresponding to the shale gas well in production, the method further includes: When the production time is shorter than the preset production time threshold, the second predicted daily gas production of the shale gas well in production at the first predicted time point is determined based on the fracturing section length of the shale gas well in production and the first predicted daily gas production.

4. The method according to claim 1, wherein The determining the target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve includes: In the case that the shale gas well to be predicted is a drilled but unproduced shale gas well, determining a target well type corresponding to the drilled but unproduced shale gas well and a second prediction time point corresponding to the drilled but unproduced shale gas well, wherein the target well type is a drilling well, a completed well, or a fractured well; Determining a third predicted daily gas production of the drilled but unproduced shale gas well corresponding to the second predicted time point based on the daily gas production reference curve; Determining the horizontal section length of a single well of the drilled but unproduced shale gas well based on the target well type, and determining the cumulative fracturing section length and cumulative horizontal section length of the produced shale gas wells in the target block; The fourth predicted daily gas production of the drilled but unproduced shale gas well is determined based on the third predicted daily gas production, the single well horizontal section length, the cumulative fracturing section length and the cumulative horizontal section length.

5. The method according to claim 4, characterized in that The determining of the horizontal section length of the single well of the drilled but unproduced shale gas well based on the target well type includes: In a case where the target well type is the drilling well, obtaining a preset horizontal section length of the drilling well as the single well horizontal section length of the drilled but unproduced shale gas well; In the case where the target well type is the completed well or the fractured well, the actual completed horizontal section length of the completed well or the fractured well is obtained as the single well horizontal section length of the drilled but unproduced shale gas well.

6. The method according to claim 1, characterized in that The determining the target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve includes: In a case where the shale gas well to be predicted is a planned deployment well, determining a fifth predicted daily gas production corresponding to the planned deployment well at a third prediction time point based on the daily gas production reference curve; Determine the cumulative fracture section length and the cumulative horizontal section length of all the shale gas wells that have been put into production in the target block, and determine the average horizontal section length corresponding to the planned deployment well based on the actual completed horizontal section length of the shale gas wells that have been put into production; A sixth predicted daily gas production of the planned deployment well is determined based on the fifth predicted daily gas production, the horizontal horizontal section length, the cumulative fracturing section length, and the cumulative horizontal section length.

7. The method according to claim 1, characterized in that Also includes: Obtaining the shale gas wells to be counted in the target block, wherein the shale gas wells to be counted include the shale gas wells that have been put into production, the shale gas wells that have been drilled but not put into production, and the planned deployment wells; Determine an average production time rate corresponding to the target block based on the historical production time of the shale gas well that has been put into production, wherein the average production time rate is associated with natural time and actual production time; For each of the shale gas wells to be counted, determining a target predicted production time period corresponding to the shale gas well to be counted based on a preset production prediction time, the average production hour rate, and a production start date corresponding to the shale gas well to be counted; The single-well predicted production of each of the shale gas wells to be counted within the corresponding target predicted production time period is determined respectively, and the target block production of the target block at the production prediction time is determined based on the single-well predicted production corresponding to all the shale gas wells to be counted in the target block.

8. A shale gas single well gas production prediction device, characterized in that: include: The data acquisition module is used to obtain the fracturing section length, original daily gas production and original pressure data of multiple shale gas wells in the target block; A curve construction module, configured to respectively construct a daily gas production reference curve and a pressure data reference curve based on the fracturing section length, the original daily gas production and the original pressure data; A gas production prediction module, configured to determine a shale gas well to be predicted in the target block, and determine a target predicted daily gas production of the shale gas well to be predicted based on the daily gas production reference curve and the pressure data reference curve; The curve construction module includes: a target gas production and pressure acquisition unit, configured to determine target daily gas production and target pressure data of the shale gas well in production based on the original daily gas production and original pressure data corresponding to the shale gas well in production; a unit fracturing stage daily gas production acquisition unit, configured to determine, for each of the shale gas wells in production, the unit fracturing stage daily gas production based on the target daily gas production and the fracturing stage length; A daily gas production reference curve construction unit is configured to determine, for each production time point, a reference daily gas production corresponding to the production time point based on the daily gas production of at least a portion of the unit fracturing stages corresponding to the plurality of shale gas wells that have been put into production, and to construct a daily gas production reference curve based on the reference daily gas productions corresponding to the plurality of production time points; a pressure data reference curve construction unit, configured to determine reference pressure data corresponding to the production time point based on at least a portion of the target pressure data corresponding to the plurality of shale gas wells that have been put into production, and to construct a pressure data reference curve based on the reference pressure data corresponding to the plurality of production time points; The target gas volume and pressure acquisition unit includes: a target daily gas production acquisition subunit, configured to obtain the target daily gas production of the shale gas well in production by taking the original daily gas production of the shale gas well in production as a benchmark and eliminating zero data in the original daily gas production; The target pressure data acquisition subunit is used to eliminate the original pressure data corresponding to the eliminated original daily gas production to obtain the target pressure data of the shale gas well that has been put into production.

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