Fracture-vug type gas field inter-well yield replacement method and device

Abstract

The invention discloses a fracture-vug gas field inter-well yield replacement method and device, and the method comprises the steps: determining a yield decline rule of a current put-into-production gas well according to historical production data, and obtaining the pre-estimated annual yield data of the put-into-production gas well; all economic well positions are determined according to actual gas reservoir geological data, and the positions and the number of gas wells to be put into production are determined according to the final recovery degree change curve; according to the single well production indication curve, reasonable production allocation corresponding to the gas well to be put into production is determined; and the production succession sequence of the to-be-produced gas well and the production time corresponding to the to-be-produced gas well are determined. According to the method, the yield decline rule of the current put-into-production gas well is determined through the historical production data of the put-into-production gas well of the fracture-vug type gas field, meanwhile, the distance factor and the economic factor are comprehensively considered, quantitative analysis of the priority weight selected by the to-be-put-into-production well position is achieved by calculating the single well priority coefficient, it is ensured that more gas is developed with low cost, and the development efficiency is improved. And the optimal economic scheme guidance is provided for optimizing the sequence of the production wells.

Description

Technical Field

[0001] The present invention relates to the technical field of gas reservoir exploitation, and particularly relates to a method and device for well - to - well production succession in a fractured - vuggy gas field. Background Technique

[0002] At present, carbonate reservoirs play an important role in oil and gas production. The fractured - vuggy carbonate reservoirs have a large scale span, including micron - scale dissolution secondary pores, tectonic micro - fractures, dissolution fractures, and meter - scale dissolution caves. This determines that there are various forms of fluid flow patterns inside the reservoir space, such as fissure flow, cave flow, and pore flow.

[0003] According to statistics, the oil and gas production of carbonate reservoirs in the world accounts for about 60% of the total world oil and gas production. The fractured - vuggy carbonate gas reservoirs represented by the Sinian system in the Tazhong No.1 and the Gaoshiti - Moxi block of Anyue gas field in China are an important force for the growth of natural gas production since the 21st century. As an important type of carbonate reservoir, the fractured - vuggy gas field has extremely strong heterogeneity, poor connectivity, and the characteristic of "one well, one reservoir". The distance between wells is relatively far. Therefore, the impact of the gas pipeline in the fractured - vuggy gas field on production cannot be ignored.

[0004] In the actual production process, due to different production start times, formation pressures, reservoir characteristics, and connection relationships with water bodies among production wells, the production stages may vary. The production well with an earlier production start time may be the first to enter the production decline stage. During the production contract period of a certain block, in order to ensure the goal of maximizing the recovery rate at the end of the contract in this area, under the limitation of the maximum annual transportation capacity of the existing pipeline, it is necessary to put into new wells, clarify the production start time of each new well in this gas reservoir, and thus clarify the optimal production succession plan for new wells in this area to ensure that the pipeline operates at the maximum gas transmission capacity for a long time. For example, during the formulation of the development plan for a certain fractured - vuggy gas field, not only factors such as reserves and production capacity need to be considered, but also multiple indicators such as pipeline transportation capacity and exploitation period need to be comprehensively considered. The optimization idea of how to maximize the benefit under the existing pipeline transportation capacity at the end of the exploitation period remains to be explored.

[0005] At present, the research on production succession mainly focuses on the succession research between combined production horizons within a single well section, such as the prior art CN114592834, a method and system for inter - stage production capacity succession in horizontal well gas injection three - dimensional development, and CN111894528, a method for multi - gas combined production and production capacity succession in coal - measure strata. However, there is little research on the succession between wells in the same gas reservoir, and the well - to - well succession optimization method is lacking, and it is impossible to optimize and sort the production start times of new wells from the overall benefit of the entire gas reservoir development.

[0006] Based on this, there is an urgent need for a method for well - to - well production succession in a fractured - vuggy gas field to enable the already - put - into - production gas field to more efficiently achieve the goal of long - term stable production and is expected to improve economic benefits. Summary of the Invention

[0007] In view of the above problems, the present invention is proposed to provide a method and device for inter-well production succession in a fractured-vuggy gas field that overcomes or at least partially solves the above problems.

[0008] Other features and advantages of the present invention will become apparent from the following detailed description, or will be learned in part through the practice of the present invention.

[0009] According to a first aspect of an embodiment of the present invention, there is provided a method for inter-well production succession in a fractured-vuggy gas field, the method for inter-well production succession in a fractured-vuggy gas field comprising:

[0010] S1. Obtain the historical production data of the gas wells that have been put into production in the fractured-vuggy gas field, determine the production decline law of the currently produced gas wells according to the historical production data, fit a corresponding production decline change curve according to the production decline law, and predict and obtain the estimated annual production data of the produced gas wells according to the production decline change curve;

[0011] S2. Determine all economic well locations according to the actual gas reservoir geological data, simulate the final recovery degree change curves corresponding to different numbers of development wells among all economic well locations at different gas production rate values through reservoir numerical simulation software, and determine the locations and quantities of the gas wells to be put into production according to the final recovery degree change curves;

[0012] S3. Obtain a single-well production indicator curve corresponding to the gas well production and the production pressure difference based on the gas production index curve method, and determine the reasonable gas production allocation corresponding to the gas wells to be put into production according to the single-well production indicator curve, where the reasonable gas production allocation is the maximum value of the single-well gas production allocation;

[0013] S4. Determine the production succession order of the gas wells to be put into production and the corresponding production start times of the gas wells to be put into production respectively according to the estimated annual production data of the produced gas wells and the reasonable gas production allocation corresponding to the gas wells to be put into production.

[0014] In some embodiments of the present invention, step S1 specifically includes:

[0015] Obtain the initial moment decline rate, the current annual production data, and the initial annual production at the start of the decline period of the production of the gas wells that have been put into production in the current year according to the obtained historical production data of the fractured-vuggy gas field;

[0016] For the annual production change law of the gas wells that have been put into production in the current year when entering the decline period, the following formula is used for fitting:

[0017]

[0018]

[0019] Wherein, a(t) is the production decline rate; a i is the decline rate at the initial moment; Q(t) is the current annual production data, m 3 / a; Q i is the initial annual production at the beginning of the decline period; n is the decline exponent;

[0020] According to the production decline law, the corresponding production decline change curve is fitted, and based on the production decline change curve, the estimated annual production data of the put-into-production gas wells are predicted.

[0021] In some embodiments of the present invention, in step S4, the production succession order of the to-be-put-into-production gas wells is judged by the single-well priority coefficient, and the judgment index is that the weight priority of the production succession order of the to-be-put-into-production gas wells is positively correlated with the single-well priority coefficient. Among them, the single-well priority coefficient is composed of the pipeline priority coefficient and the production priority coefficient through weighting, and the calculation formula is as follows:

[0022]

[0023]

[0024]

[0025]

[0026]

[0027] Wherein, η j is the single-well priority coefficient of the j-th single well; y G is the weight of the production priority coefficient; is the production priority coefficient of the j-th single well; is the pipeline priority coefficient of the j-th single well; y l is the weight of the pipeline priority coefficient of the j-th single well; is the reasonable production allocation of the j-th single well; is the sum of the production allocations of all to-be-put-into-production gas wells, m is the total number of to-be-put-into-production gas wells, and m is a positive integer; L j is the distance from the j-th single well to the gas field gathering station pipeline; p G is the unit production cost; p line is the cost per meter of pipeline.

[0028] In some embodiments of the present invention, in step S4, the production time of the to-be-put-into-production gas wells is determined according to the maximum pipeline transportation volume. Among them, according to the production succession order of the to-be-put-into-production gas wells and the corresponding reasonable production allocation, the year when the fracture-vug type gas field maintains the maximum pipeline transportation volume is the production time of the corresponding to-be-put-into-production gas well.

[0029] In some embodiments of the present invention, in step S4, the method further includes: when the sum of the reasonable production allocation of the currently succeeding gas well to be put into production and the production allocation of the already-produced gas wells is less than the maximum pipeline transportation volume of the fracture-vug type gas field, calculating and determining the production start time of the subsequent succeeding gas wells to be put into production respectively, and the production allocation result of the subsequent succeeding gas wells to be put into production is the difference between the sum of the production allocations of the already-produced gas wells and the maximum pipeline transportation volume of the fracture-vug type gas field, so as to maintain the maximum pipeline transportation volume of the fracture-vug type gas field.

[0030] According to a second aspect of the embodiments of the present invention, there is provided a device for inter-well production succession in a fracture-vug type gas field, the device for inter-well production succession in a fracture-vug type gas field includes:

[0031] A production decline calculation module, configured to obtain the historical production data of the already-produced gas wells in the fracture-vug type gas field, determine the production decline law of the currently already-produced gas wells according to the historical production data, fit a corresponding production decline change curve according to the production decline law, and predict and obtain the estimated annual production data of the already-produced gas wells according to the production decline change curve;

[0032] A well location determination module, configured to determine all economic well locations according to the actual gas reservoir geological data, simulate the final recovery degree change curves corresponding to different numbers of development wells among all economic well locations under different gas production rate values through reservoir numerical simulation software, and determine the location and quantity of the gas wells to be put into production according to the final recovery degree change curves;

[0033] A production allocation calculation module, configured to obtain a single-well production indication curve corresponding to the gas well production and the production pressure difference based on the gas production index curve method, and determine the reasonable production allocation corresponding to the gas well to be put into production according to the single-well production indication curve, where the reasonable production allocation is the maximum value of the single-well production allocation;

[0034] A well location succession calculation module, configured to determine the production succession order of the gas wells to be put into production and the production start time corresponding to the gas wells to be put into production respectively according to the estimated annual production data of the already-produced gas wells and the reasonable production allocation corresponding to the gas wells to be put into production.

[0035] In some embodiments of the present invention, the production decline calculation module is specifically configured to:

[0036] According to the obtained historical production data of the fracture-vug type gas field, obtain the initial moment decline rate of the production of the already-produced gas wells in the current year, the current annual production data, and the initial annual production in the decline period;

[0037] For the annual production change law of the already-produced gas wells in the current year entering the decline period, the following formula is used for fitting:

[0038]

[0039]

[0040] where a(t) is the production decline rate; a i is the decline rate at the initial moment; Q(t) is the current annual production data, m 3 / a; Q i is the initial annual production at the beginning of the decline period; n is the decline exponent;

[0041] According to the production decline law, the corresponding production decline change curve is fitted, and based on the production decline change curve, the estimated annual production data of the put-into-production gas wells are predicted.

[0042] In some embodiments of the present invention, the well position succession calculation module is configured to: use the single-well priority coefficient as a judgment index according to the production succession order of the to-be-produced gas wells, and the judgment index is positively correlated with the weight priority of the production succession order of the to-be-produced gas wells. Among them, the single-well priority coefficient is composed of a pipeline priority coefficient and a production priority coefficient through weighting, and the calculation formula is as follows:

[0043]

[0044]

[0045]

[0046]

[0047]

[0048] where η j is the single-well priority coefficient of the j-th single well; y G is the weight of the production priority coefficient; is the production priority coefficient of the j-th single well; is the pipeline priority coefficient of the j-th single well; y l is the weight of the pipeline priority coefficient of the j-th single well; is the reasonable production allocation of the j-th single well; is the sum of the production allocations of all to-be-produced gas wells, m is the total number of to-be-produced gas wells, and m is a positive integer; L j is the distance from the j-th single well to the gas field gathering station pipeline; p G is the unit production cost; p line is the cost per meter of pipeline.

[0049] In some embodiments of the present invention, the well position succession calculation module is configured to: determine the production time of the to-be-produced gas wells according to the maximum pipeline transportation volume, wherein, according to the production succession order of the to-be-produced gas wells and the corresponding reasonable production allocations, the year when the fractured-vuggy gas field maintains the maximum pipeline transportation volume is the production time of the corresponding to-be-produced gas wells.

[0050] In some embodiments of the present invention, the well position succession calculation module is configured to: when the sum of the reasonable production allocation of the gas wells to be put into production in the current succession and the production allocation of the gas wells that have been put into production is less than the maximum pipeline transportation volume of the fracture-vug type gas field, calculate and determine the production start time of the subsequent gas wells to be put into production to be succeeded respectively, and the production allocation result of the subsequent gas wells to be put into production to be succeeded is the difference between the sum of the production allocations of the gas wells that have been put into production and the maximum pipeline transportation volume of the fracture-vug type gas field, so as to maintain the maximum pipeline transportation volume of the fracture-vug type gas field.

[0051] The technical solution provided in the embodiments of the present invention has at least the following technical effects or advantages:

[0052] A method and device for inter-well production succession in a fracture-vug type gas field provided in an embodiment of the present invention. The method for inter-well production succession in a fracture-vug type gas field determines the production decline law of the currently produced gas wells through the historical production data of the produced gas wells in the fracture-vug type gas field, so as to estimate the subsequent production of the produced gas wells, which can be used as a reference for the subsequent gas wells to be put into production to be succeeded. At the same time, considering the distance factor and economic factor comprehensively, by calculating the single-well priority coefficient composed of the weighted pipeline priority coefficient and production priority coefficient, a quantitative analysis of the priority weight for the selection of the well positions to be put into production is realized, ensuring the development of as much gas volume as possible with as little cost as possible, and providing an optimal economic scheme guidance for optimizing the production start well sequence.

[0053] The above description is only an overview of the technical solution of the present invention. In order to be able to understand the technical means of the present invention more clearly, it can be implemented according to the content of the description. And in order to make the above and other purposes, features and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention are given below. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0055] Figure 1 It is a schematic flow chart of a method for inter-well production succession in a fracture-vug type gas field according to the present invention;

[0056] Figure 2 It is a reference schematic diagram of the production decline change curve of the annual production of the produced gas wells with time;

[0057] Figure 3 It is a reference schematic diagram of all economic well positions in a fracture-vug type gas field;

[0058] Figure 4It is a reference schematic diagram of the variation curve of the final recovery degree;

[0059] Figure 5 It is a reference schematic diagram of the gas production indication curve of a single well;

[0060] Figure 6 It is a reference schematic diagram of the gas production indication curve of the single well of the gas well X-5 to be put into production;

[0061] Figure 7 It is a reference schematic diagram of the gas production indication curve of the single well of the gas well X-6 to be put into production;

[0062] Figure 8 It is a reference schematic diagram of the production prediction after the optimization of the production replacement between wells;

[0063] Figure 9 It is a schematic diagram of the principle structure of the device for replacing production between wells in the fracture-vug type gas field described in the present invention. Detailed implementation manners

[0064] Hereinafter, exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings.

[0065] Various schematic structural diagrams according to embodiments of the present disclosure are shown in the drawings. These figures are not drawn to scale, in which for the purpose of clear expression, some details are enlarged and some details may be omitted. The shapes of various regions and layers shown in the figures, as well as their relative sizes and positional relationships, are merely exemplary. In practice, there may be deviations due to manufacturing tolerances or technical limitations, and those skilled in the art can design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0066] In the context of the present disclosure, when a layer / component is referred to as being "on" another layer / component, the layer / component can be directly on the other layer / component, or there may be an intermediate layer / component between them. Additionally, if a layer / component is "on" another layer / component in one orientation, then when the orientation is reversed, the layer / component can be "under" the other layer / component. In the context of the present disclosure, similar or identical components may be denoted by the same or similar reference numerals.

[0067] In order to better understand the above technical solutions, the above technical solutions will be described in detail below in combination with specific implementation manners. It should be understood that the embodiments of the present disclosure and the specific features in the embodiments are detailed descriptions of the technical solutions of the present application, rather than limitations on the technical solutions of the present application. Without conflict, the technical features in the embodiments of the present application and the embodiments can be combined with each other.

[0068] Figure 1It is a schematic flow chart of a method for inter-well production replacement in a fracture-cavity gas field provided by an embodiment of the present invention. As Figure 1 shown, the method for inter-well production replacement in the fracture-cavity gas field includes:

[0069] S1. Obtain the historical production data of the already-produced gas wells in the fracture-cavity gas field, determine the production decline law of the currently already-produced gas wells according to the historical production data, fit a corresponding production decline change curve according to the production decline law, and predict and obtain the estimated annual production data of the already-produced gas wells according to the production decline change curve;

[0070] In the embodiment of the present invention, in step S1, the obtaining of the historical production data of the already-produced gas wells in the fracture-cavity gas field and determining the production decline law of the already-produced gas wells in the current year according to the historical production data include:

[0071] According to the obtained historical production data of the fracture-cavity gas field, obtain the initial moment decline rate of the production of the already-produced gas wells in the current year, the current annual production data, and the initial annual production in the decline period;

[0072] For the annual production change law of the already-produced gas wells in the current year entering the decline period, the following formula is used for fitting:

[0073]

[0074]

[0075] In the formula, a(t) is the production decline rate, which changes with time; a i is the initial moment decline rate, determined by the historical production data, and is a fixed value; Q(t) is the current annual production data, which changes with time, m 3 / a; Q i is the initial annual production in the decline period, determined by the historical production data, and is a fixed value; n is the decline index, and its value range is [0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1], and n takes the value with the highest fitting correlation coefficient as the final fitting parameter.

[0076] In the embodiment of the present invention, according to the annual production change law in the decline period, the production of the already-produced gas wells in the current year is predicted by using reservoir numerical simulation software.

[0077] Referring to Figure 2 shown, in the embodiment of the present invention, the production of the already-produced gas wells is predicted by using reservoir numerical simulation software. Figure 2 It is a reference schematic diagram of the production decline change curve of the annual production of the already-produced gas wells changing with time.

[0078] S2. Determine all economic well positions according to the actual gas reservoir geological data. By using reservoir numerical simulation software, simulate the variation curves of the ultimate recovery factor corresponding to different numbers of development wells among all economic well positions under different gas production rates. Determine the positions and quantities of the gas wells to be put into production according to the said variation curves of the ultimate recovery factor.

[0079] In an embodiment of the present invention, for example, refer to Figure 3 as shown in Figure 3 which is a reference schematic diagram of the controlled reserves of single non - put - into - production wells in a fractured - vuggy gas field. First, determine all economic well positions according to the actual geological data of the X fractured - vuggy gas field. Among them, X - 1, X - 2, X - 3, and X - 4 are the gas wells that have been put into production, and X - 5, X - 6, X - 7, and X - 8 are all economic well positions that have not been put into production. Their naming numbers can increase as the controlled reserves of a single well decrease. There can be different naming rules according to actual needs, and the present invention has no limitation in this regard. Table 1 is the reference table of the controlled reserves of single non - put - into - production wells in the X fractured - vuggy gas field.

[0080] Table 1 Reference table of the controlled reserves of single non - put - into - production wells in the X fractured - vuggy gas field

[0081]

[0082] In the embodiment of the present invention, the variation curve of the ultimate recovery factor with different numbers of development wells is simulated by using reservoir numerical simulation software. Specifically, in the simulation process of the embodiment of the present invention, the number of development wells is increased based on the principle of giving priority to high - reserve control. The simulation results are as Figure 4 shown. According to the plotted variation curve of the ultimate recovery factor corresponding to the ultimate recovery factor and the number of development wells, taking the abscissa corresponding to the inflection point of the variation curve of the ultimate recovery factor as the optimal number of development wells, and its determination principle is to develop as much gas volume as possible with as little cost as possible. Then, it can be determined that the number of economic development wells is 6, that is, the gas wells to be put into production are determined as X - 5 and X - 6.

[0083] S3. Obtain the single - well production indicator curve corresponding to the gas well production and the production pressure difference based on the gas production index curve method. Determine the reasonable gas production allocation corresponding to the gas wells to be put into production according to the said single - well production indicator curve. The said reasonable gas production allocation is the maximum value of the single - well gas production allocation.

[0084] In the embodiment of the present invention, the reasonable gas production allocation of each gas well to be put into production is determined according to the gas production indicator curve method. The gas production index is the gas production volume under a unit production pressure difference, and the size of the gas production index is equal to the ratio of the gas well production to the production pressure difference. The larger the gas production index, the more favorable it is for the production of the gas well. When the gas well production is low, the natural gas flows slowly in the reservoir, and the gas production indicator curve is a straight line. When the gas well production is high, the natural gas is in non - Darcy flow in the reservoir, and the gas production indicator curve is a curve, and additional non - Darcy flow resistance needs to be overcome, which affects the gas well production.

[0085] Figure 5It is a reference schematic diagram of the gas production indication curve for a single well. As the gas production rate (assigned production) increases, the gas production indication curve changes from a straight line to a curve, and the slope becomes larger and larger, that is, the gas production volume under a unit production pressure difference becomes smaller and smaller, and the energy required to produce a unit volume of natural gas becomes more and more. To ensure the reasonable energy consumption of the gas well and ensure that the gas well has a stable production period and recovery rate as long as possible, the embodiment of the present invention selects the inflection point that deviates from the straight line segment earliest as the reasonable assigned production of the gas well.

[0086] Refer to Figures 6-7 as shown Figure 6 It is a reference schematic diagram of the gas production indication curve for a single well of the to-be-produced gas well X-5. Figure 7 It is a reference schematic diagram of the gas production indication curve for a single well of the to-be-produced gas well X-6. According to Figure 6 it can be determined that the reasonable assigned production of the to-be-produced gas well X-5 is 500×10 3 m 3 / d. According to Figure 7 it can be determined that the reasonable assigned production of the to-be-produced gas well X-6 is 300×10 3 m 3 / d.

[0087] S4. According to the estimated annual production data of the already-produced gas wells and the reasonable assigned production corresponding to the to-be-produced gas wells, respectively determine the production succession order of the to-be-produced gas wells and the corresponding production start times of the to-be-produced gas wells.

[0088] In the embodiment of the present invention, in step S4, the production succession order of the to-be-produced gas wells uses the single-well priority coefficient as a judgment index. The judgment index is that the weight priority of the production succession order of the to-be-produced gas wells is positively correlated with the single-well priority coefficient. The larger the single-well priority coefficient, the higher the weight priority of the production succession order of the to-be-produced gas well. Specifically, it includes two factors, namely the distance factor and the economic factor; the distance factor considers the difference in the distance between the single well and the gas field gas gathering station. As the distance increases, the production priority decreases; the economic factor considers the difference in the controlled reserves of the single well. As the well-controlled reserves increase, the production priority increases.

[0089] Among them, the single-well priority coefficient is composed of a pipeline priority coefficient (i.e., the distance factor) and a production priority coefficient (i.e., the economic factor) through weighting. The calculation formula is as follows:

[0090]

[0091]

[0092]

[0093]

[0094]

[0095] In the formula, η j is the single-well priority coefficient of the j-th single well; y G is the weight of the production priority coefficient; is the production priority coefficient of the j-th single well; is the pipeline priority coefficient of the j-th single well; y l is the weight of the pipeline priority coefficient of the j-th single well; is the reasonable production allocation of the j-th single well; is the sum of the production allocations of all gas wells to be put into production, m is the total number of gas wells to be put into production, and m is a positive integer; L j is the distance from the j-th single well to the gas gathering station pipeline of the gas field; p G is the cost per unit production; p line is the cost per meter of pipeline.

[0096] For example, according to the above calculation formula of the single-well priority coefficient, calculate the single-well priority coefficients corresponding to the gas well X-5 to be put into production and the gas well X-6 to be put into production respectively, and the calculation parameters are shown in Table 2 below.

[0097] Table 2 Calculation parameter table of single-well priority coefficients of gas wells X-5 and X-6 to be put into production

[0098]

[0099] Among them, the construction cost per meter of the pipeline is 30 yuan / meter, and the cost per unit production is 3 yuan / cubic meter. The distance from the gas well X-5 to be put into production to the gas gathering station of this gas field is 15.6 km, and the distance from the gas well X-6 to be put into production to the gas gathering station of this gas field is 30.8 km. Since the single-well priority coefficient of the gas well X-5 to be put into production is greater than that of the gas well X-6 to be put into production, that is, the priority weight of the gas well X-5 to be put into production is greater than that of the gas well X-6 to be put into production, it is determined to put X-5 into production first and then X-6.

[0100] In the embodiment of the present invention, the production time of the gas well to be put into production is determined according to the maximum pipeline transportation volume. Among them, according to the production succession order of the gas well to be put into production and the corresponding reasonable production allocation, the year when the fractured-vuggy gas field maintains the maximum pipeline transportation volume is the production time of the corresponding gas well to be put into production.

[0101] Specifically, the embodiment of the present invention takes the maximum pipeline transportation volume Q max as a constraint, and based on the production order (assuming the single-well priority coefficient ranking: Well-4 > Well-3 > Well-2 > Well-1) and the single-well production allocation result, the year when the pipeline transportation capacity of the fractured-vuggy gas field always maintains the maximum transportation capacity is the production time of the corresponding gas well to be put into production. Among them, if the maximum pipeline transportation volume Q maxIf the difference between the predicted annual production of the gas field in the next year by the fitting formula in step S1 and the production allocation of the to-be-commissioned gas well Well-4 is less than the production allocation of Well-4, then the difference between the two is used as the production allocation of Well-4 (the single-well production allocation determined here is less than or equal to the reasonable production allocation determined in step S3). In subsequent production years, the production allocation of the to-be-commissioned gas well Well-4 is increased sequentially to meet the maximum pipeline throughput Q. max When the production allocation of Well-4 reaches the maximum production allocation of this well (the reasonable production allocation determined in step S3) and still cannot meet the maximum pipeline throughput Q max the year is the commissioning time of the second to-be-commissioned gas well Well-3.

[0102] For example, in the embodiment of the present invention, the corresponding predicted annual production data are obtained according to the production decline law of the commissioned gas wells obtained in step S1, and it can be known from Figure 2 that the commissioned gas wells start to enter the decline stage in 2030. With the constraint of the maximum pipeline throughput of 1.1 billion cubic meters, the to-be-commissioned gas well X-5 should be commissioned in 2030 with an annual production of 0.1325 billion cubic meters. According to the reasonable production allocation of the to-be-commissioned gas well X-5, the maximum annual production of X-5 is 1.8 billion cubic meters. Then, when the sum of the annual production of all gas wells except the to-be-commissioned gas well X-5 is less than 11 - 1.8 = 9.2 billion cubic meters, it is the commissioning time of the second new well. At this time, the to-be-commissioned gas well X-6 should be commissioned in 2033 with an annual production of 0.218 billion cubic meters. According to the reasonable production allocation of the to-be-commissioned gas well X-5, the maximum annual production of X-5 is 1.08 billion cubic meters.

[0103] In step S4, the method in the embodiment of the present invention further includes: when the sum of the reasonable production allocation of the currently succeeding to-be-commissioned gas well and the production allocation of the commissioned gas wells is less than the maximum pipeline throughput of the fracture-vug type gas field, calculate and determine the commissioning time of the subsequent succeeding to-be-commissioned gas wells respectively, and the production allocation result of the subsequent succeeding to-be-commissioned gas wells is the difference between the sum of the production allocations of the commissioned gas wells (the previous to-be-commissioned gas wells are in the commissioned state at this time) and the maximum pipeline throughput of the fracture-vug type gas field, so as to maintain the maximum pipeline throughput of the fracture-vug type gas field.

[0104] Specifically, after the gas well to be put into production (such as X-5) is put into production, if the production allocation of the newly added X-5 reaches the maximum value, and the sum of the production allocation of the currently put into production gas wells cannot meet the maximum pipeline transportation volume of the fractured-vuggy gas field, then a new gas well X-6 to be put into production needs to be added at this time. If there are multiple gas wells to be put into production, it is necessary to repeat step S1 to obtain the production decline change curve corresponding to the currently put into production gas wells and the estimated annual production data respectively, and then determine the production replacement order of the gas wells to be put into production and the corresponding production time according to step S4, and repeat step S1 and step S4 to continue production in sequence until all the gas wells to be put into production are put into production, then the well-to-well production optimization replacement plan of the gas reservoir is completed, that is, the production replacement order of the gas wells to be put into production and the corresponding production time are determined; refer to Figure 8 As shown, repeat step S1 to obtain the production decline law of the entire fractured-vuggy gas field after putting X-5 and X-6 into production, and then repeat step S4 to determine the production time of the third and fourth gas wells to be put into production. For every two newly added gas wells to be put into production, it is necessary to repeat step S1 and step S4 until all the newly added gas wells to be put into production are put into production.

[0105] The method for well-to-well production replacement in the fractured-vuggy gas field described in the embodiment of the present invention has the following advantages compared with the prior art:

[0106] 1. Determine the production decline law of the currently put into production gas wells through the historical production data of the put into production gas wells in the fractured-vuggy gas field, so as to estimate the subsequent production of the put into production gas wells, which can be used as a reference for the subsequent replaced gas wells to be put into production;

[0107] 2. Considering the distance factor and economic factor comprehensively, by calculating the single-well priority coefficient weighted by the pipeline priority coefficient and the production priority coefficient, the quantitative analysis of the priority weight of the selection of the gas well to be put into production is realized, ensuring that as much gas volume as possible is developed at the lowest cost, and providing the optimal economic scheme guidance for optimizing the production order of the production wells;

[0108] 3. At the same time, according to the estimated annual production data of the put into production gas wells and the reasonable production allocation corresponding to the gas wells to be put into production, determine the production replacement order of the gas wells to be put into production and the corresponding production time respectively. Constrained by the maximum pipeline transportation volume, the production time of a single well to be put into production is determined, the stable production period of the entire gas field is extended, the development of the entire gas field is managed with the concept of the whole life cycle, the efficient development of the gas field is realized, the problem of optimizing the production replacement with variable pipeline maximum transportation capacity is solved, it is applicable to the situation where multiple gas wells are put into production in the same year, and the weight function in the constructed production order judgment model is not affected by human factors, the calculation is simple, and it is easy to operate, with better applicability.

[0109] On the basis of the above embodiment, the present invention also provides a device for well-to-well production replacement in a fractured-vuggy gas field, refer to Figure 9As shown Figure 9 is a schematic diagram of the principle structure of the well - to - well production replacement device for the fracture - cavity type gas field of the present invention. The well - to - well production replacement device for the fracture - cavity type gas field includes:

[0110] A production decline calculation module 100, which is used to obtain the historical production data of the gas wells that have been put into production in the fracture - cavity type gas field, determine the production decline law of the currently put - into - production gas wells according to the historical production data, fit the corresponding production decline change curve according to the production decline law, and predict and obtain the estimated annual production data of the put - into - production gas wells according to the production decline change curve;

[0111] A well location determination module 200, which is used to determine all economic well locations according to the actual gas reservoir geological data, simulate the change curves of the ultimate recovery degree corresponding to different numbers of development wells among all economic well locations under different gas production rate values through reservoir numerical simulation software, and determine the location and quantity of the gas wells to be put into production according to the ultimate recovery degree change curves;

[0112] A production allocation calculation module 300, which is used to obtain the single - well production indicator curve corresponding to the gas well production and the production pressure difference based on the gas production index curve method, and determine the reasonable production allocation corresponding to the gas wells to be put into production according to the single - well production indicator curve. The reasonable production allocation is the maximum value of the single - well production allocation;

[0113] A well location replacement calculation module 400, which is used to determine the production replacement order of the gas wells to be put into production and the corresponding production start time of the gas wells to be put into production respectively according to the estimated annual production data of the put - into - production gas wells and the reasonable production allocation corresponding to the gas wells to be put into production.

[0114] In the embodiment of the present invention, the production decline calculation module 100 is specifically used for:

[0115] According to the obtained historical production data of the fracture - cavity type gas field, obtain the initial - moment decline rate of the production of the gas wells put into production in the current year, the current annual production data, and the initial annual production in the decline period;

[0116] For the annual production change law of the gas wells put into production in the current year entering the decline period, the following formula is used for fitting:

[0117]

[0118]

[0119] In the formula, a(t) is the production decline rate; a i is the initial - moment decline rate; Q(t) is the current annual production data, m 3 / a; Q i is the initial annual production in the decline period; n is the decline index;

[0120] According to the production decline law, the corresponding production decline curve is fitted, and the estimated annual production data of the put-into-production gas wells are predicted based on the production decline curve.

[0121] In an embodiment of the present invention, the well position succession calculation module 400 is configured to: use the single-well priority coefficient as a judgment index according to the production succession order of the to-be-produced gas wells, and the judgment index is positively correlated with the weight priority of the production succession order of the to-be-produced gas wells. Among them, the single-well priority coefficient is composed of a pipeline priority coefficient and a production priority coefficient through weighting, and the calculation formula is as follows:

[0122]

[0123]

[0124]

[0125]

[0126]

[0127] In the formula, η j is the single-well priority coefficient of the j-th single well; y G is the weight of the production priority coefficient; is the production priority coefficient of the j-th single well; is the pipeline priority coefficient of the j-th single well; y l is the weight of the pipeline priority coefficient of the j-th single well; is the reasonable production allocation of the j-th single well; is the sum of the production allocations of all to-be-produced gas wells, m is the total number of to-be-produced gas wells, and m is a positive integer; L j is the distance from the j-th single well to the gas field gathering station pipeline; p G is the unit production cost; p line is the cost per meter of pipeline.

[0128] In an embodiment of the present invention, the well position succession calculation module 400 is configured to: determine the production time of the to-be-produced gas wells according to the maximum pipeline transportation volume, wherein, according to the production succession order of the to-be-produced gas wells and the corresponding reasonable production allocations, the year when the fracture-vug type gas field maintains the maximum pipeline transportation volume is the production time of the corresponding to-be-produced gas wells.

[0129] In an embodiment of the present invention, the well position succession calculation module 400 is configured to: when the sum of the reasonable production allocation of the to-be-produced gas well currently in succession and the production allocation of the already-produced gas well is less than the maximum pipeline transportation volume of the fracture-vug type gas field, calculate and determine the production start time of the subsequent to-be-produced gas well in succession respectively, and the production allocation result of the subsequent to-be-produced gas well in succession is the difference between the sum of the production allocations of the already-produced gas wells and the maximum pipeline transportation volume of the fracture-vug type gas field, so as to maintain the maximum pipeline transportation volume of the fracture-vug type gas field.

[0130] The fracture-vug type gas field well-to-well production succession device described in the embodiment of the present invention can execute the fracture-vug type gas field well-to-well production succession method provided in the above embodiment. The fracture-vug type gas field well-to-well production succession device has the corresponding functional steps and beneficial effects of the fracture-vug type gas field well-to-well production succession method described in the above embodiment. For details, please refer to the embodiment of the fracture-vug type gas field well-to-well production succession method. The embodiment of the present invention will not be elaborated here.

[0131] The embodiment of the present invention further provides an electronic device, which may include a processor and a memory, and the processor and the memory may be connected through a bus or other means. The processor may be a central processing unit (CPU). The processor may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. chips, or a combination of the above various chips. The memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the fracture-vug type gas field well-to-well production succession method in the embodiment of the present invention. The processor executes various functional applications and data processing of the processor by running the non-transitory software programs, instructions, and modules stored in the memory, that is, to implement the fracture-vug type gas field well-to-well production succession method in the above method embodiment.

[0132] The memory may include a program storage area and a data storage area. Among them, the program storage area may store an operating system and application programs required for at least one function; the data storage area may store data created by the processor, etc. In addition, the memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one magnetic disk storage device, flash memory device, or other non-transitory solid-state storage devices. The one or more modules are stored in the memory and, when executed by the processor, execute as Figure 1The method for replacing well - to - well production in a fractured - vuggy gas field in the illustrated embodiment. The specific details of the above - mentioned electronic device can be correspondingly referred to Figure 1 the relevant descriptions and effects corresponding to the illustrated embodiment for understanding, which will not be elaborated here. Those skilled in the art can understand that to implement all or part of the processes in the above - mentioned embodiment methods, it can be completed by instructing relevant hardware through a computer program. The program can be stored in a computer - readable storage medium. When the program is executed, it can include the processes of the above - mentioned method embodiments. Among them, the storage medium can be a Read - Only Memory (ROM), a Random Access Memory (RAM), a Flash Memory, a Hard Disk Drive (abbreviation: HDD), or a Solid - State Drive (SSD), etc.; the storage medium can also include a combination of the above - mentioned types of memories.

[0133] In the specification provided here, a large number of specific details are described. However, it can be understood that the embodiments of the present invention can be practiced without these specific details. In some instances, well - known methods, structures, and technologies are not shown in detail so as not to obscure the understanding of this specification.

[0134] Similarly, it should be understood that in order to streamline the present disclosure and help understand one or more of the various inventive aspects, in the above description of the exemplary embodiments of the present invention, the various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, the disclosed method should not be construed as reflecting the intention that the claimed invention requires more features than those expressly recited in each claim. Rather, as reflected in the following claims, the inventive aspects lie in less than all the features of the single embodiment disclosed previously. Therefore, the claims following the detailed description are hereby expressly incorporated into the detailed description, where each claim itself serves as a separate embodiment of the present invention.

[0135] It should be noted that the above - mentioned embodiments illustrate the present invention rather than limit the present invention, and those skilled in the art can design alternative embodiments without departing from the scope of the appended claims.

Claims

1. A method for well - to - well production succession in a fractured - vuggy gas field, characterized in that, The method for inter-well production replacement in a fractured-vuggy gas field includes: S1. Obtain the historical production data of the already-produced gas wells in the fractured-vuggy gas field, determine the production decline law of the currently already-produced gas wells according to the historical production data, fit the corresponding production decline change curve according to the production decline law, and predict and obtain the estimated annual production data of the already-produced gas wells according to the production decline change curve; S2. Determine all economic well positions according to the actual gas reservoir geological data, simulate the change curves of the ultimate recovery degree corresponding to different numbers of development wells among all economic well positions under different gas production rate values through reservoir numerical simulation software, and determine the positions and quantities of the gas wells to be put into production according to the ultimate recovery degree change curves; S3. Obtain the single-well production indicator curve corresponding to the gas well production and the production pressure difference based on the gas production index curve method, and determine the reasonable production allocation corresponding to the gas wells to be put into production according to the single-well production indicator curve, where the reasonable production allocation is the maximum value of the single-well production allocation; S4. Determine the production replacement sequence of the gas wells to be put into production and the corresponding production start time of the gas wells to be put into production respectively according to the estimated annual production data of the already-produced gas wells and the reasonable production allocation corresponding to the gas wells to be put into production.

2. The method for inter-well production succession in a fractured-vuggy gas field according to claim 1, wherein Step S1 specifically includes: According to the obtained historical production data of the fractured-vuggy gas field, obtain the initial moment decline rate of the production of the already-produced gas wells in the current year, the current annual production data, and the initial annual production in the decline period; For the annual production change law of the already-produced gas wells in the current year entering the decline period, the following formula is used for fitting: Where a(t) is the production decline rate; a i is the decline rate at the initial moment; Q(t) is the current annual production data, m 3 / a;Q i is the initial annual output of the decline period; n is the decline index; Fit the corresponding production decline change curve according to the production decline law, and predict and obtain the estimated annual production data of the already-produced gas wells according to the production decline change curve.

3. The method for replacing well - to - well production in a fractured - vuggy gas field according to claim 1, wherein In step S4, the production replacement sequence of the gas wells to be put into production uses the single-well priority coefficient as the judgment index, and the judgment index is that the weight priority of the production replacement sequence of the gas wells to be put into production is positively correlated with the single-well priority coefficient, where the single-well priority coefficient is composed of the pipeline priority coefficient and the production priority coefficient weighted, and the calculation formula is as follows: Where, η j is the single-well priority coefficient of the j-th single well; y G is the weight of the production priority coefficient; is the production priority coefficient of the j-th single well; is the pipeline priority coefficient of the j-th single well; y l is the weight of the pipeline priority coefficient of the j-th single well; is the reasonable production allocation of the j-th single well; is the sum of the production allocations of all gas wells to be put into production, m is the total number of gas wells to be put into production, and m is a positive integer; L j is the distance from the j-th single well to the gas gathering station pipeline of the gas field; p G is the cost per unit of production; p line is the cost per meter of pipeline.

4. The method for inter-well production succession in a fracture-vug gas field according to claim 1, wherein In step S4, the production start time of the gas wells to be put into production is determined according to the maximum pipeline transportation volume. Among them, according to the production replacement sequence of the gas wells to be put into production and the corresponding reasonable production allocation, the year when the fractured-vuggy gas field maintains the maximum pipeline transportation volume is the production start time of the corresponding gas wells to be put into production.

5. The method for well - to - well production succession in fractured - vuggy gas fields according to claim 4, wherein In step S4, the method further includes: when the sum of the reasonable production allocation of the currently replaced gas wells to be put into production and the production allocation of the already-produced gas wells is less than the maximum pipeline transportation volume of the fractured-vuggy gas field, calculate and determine the production start times of the subsequent replaced gas wells to be put into production respectively, and the production allocation result of the subsequent replaced gas wells to be put into production is the difference between the sum of the production allocations of the already-produced gas wells and the maximum pipeline transportation volume of the fractured-vuggy gas field, so as to maintain the maximum pipeline transportation volume of the fractured-vuggy gas field.

6. A device for replacing well - to - well production in a fracture - cave gas field, characterized in that, The device for inter-well production replacement in a fractured-vuggy gas field includes: A production decline calculation module, which is used to obtain the historical production data of the already-produced gas wells in the fractured-vuggy gas field, determine the production decline law of the currently already-produced gas wells according to the historical production data, fit the corresponding production decline change curve according to the production decline law, and predict and obtain the estimated annual production data of the already-produced gas wells according to the production decline change curve; The well location determination module is used to determine all economic well locations according to the actual gas reservoir geological data, simulate the final recovery degree change curves corresponding to different numbers of development wells among all economic well locations under different gas production rate values through reservoir numerical simulation software, and determine the location and quantity of gas wells to be put into production according to the final recovery degree change curves; The production allocation calculation module is used to obtain the single-well production indication curve corresponding to the gas well production and the production pressure difference based on the gas production index curve method, and determine the reasonable production allocation corresponding to the gas wells to be put into production according to the single-well production indication curve. The reasonable production allocation is the maximum value of the single-well production allocation; The well location succession calculation module is used to determine the production succession order of the gas wells to be put into production and the corresponding production time of the gas wells to be put into production respectively according to the estimated annual production data of the gas wells that have been put into production and the reasonable production allocation corresponding to the gas wells to be put into production.

7. The inter-well production succession device for fractured-vuggy gas fields according to claim 6, characterized in that, The specific operation of the production decline calculation module is as follows: Based on the historical production data of the fractured-vuggy gas field obtained, obtain the initial moment decline rate of the production of the gas wells that have been put into production in the current year, the current annual production data, and the initial annual production in the decline period; For the annual production change law of the gas wells that have been put into production in the current year when entering the decline period, the following formula is used for fitting: In the formula, a(t) is the production decline rate; a i is the decline rate at the initial moment; Q(t) is the current annual production data, m 3 / a; Q i is the initial annual production at the beginning of the decline period; n is the decline exponent; According to the production decline law, fit the corresponding production decline change curve, and predict and obtain the estimated annual production data of the gas wells that have been put into production according to the production decline change curve.

8. The inter-well production replacement device for fractured-vuggy gas fields according to claim 6, characterized in that The well location succession calculation module is used to: take the single-well priority coefficient as the judgment index according to the production succession order of the gas wells to be put into production. The judgment index is positively correlated with the weight priority of the production succession order of the gas wells to be put into production. Among them, the single-well priority coefficient is composed of the pipeline priority coefficient and the production priority coefficient through weighting, and the calculation formula is as follows: Where η j is the single - well priority coefficient of the j - th single well; y G is the weight of the production - priority coefficient; is the production - priority coefficient of the j - th single well; is the pipeline - priority coefficient of the j - th single well; y l is the weight of the pipeline - priority coefficient of the j - th single well; is the reasonable production allocation of the j - th single well; is the sum of the production allocations of all gas wells to be put into production, m is the total number of gas wells to be put into production, and m is a positive integer; L j is the distance from the j - th single well to the pipeline of the gas - field gathering station; p G is the cost per unit of production; p line is the cost per meter of pipeline.

9. The inter-well production succession device for a fractured-vuggy gas field according to claim 6, characterized in that, The well location succession calculation module is used to: determine the production time of the gas wells to be put into production according to the maximum pipeline transportation volume. Among them, according to the production succession order of the gas wells to be put into production and the corresponding reasonable production allocation, the year when the fractured-vuggy gas field maintains the maximum pipeline transportation volume is the production time corresponding to the gas wells to be put into production.

10. The inter-well production succession device for fractured-vuggy gas fields according to claim 9, characterized in that, The well location succession calculation module is used to: when the sum of the reasonable production allocation of the gas wells to be put into production currently being succeeded and the production allocation of the gas wells that have been put into production is less than the maximum pipeline transportation volume of the fractured-vuggy gas field, calculate and determine the production time of the subsequent gas wells to be put into production respectively, and the production allocation result of the subsequent gas wells to be put into production is the difference between the sum of the production allocations of the gas wells that have been put into production and the maximum pipeline transportation volume of the fractured-vuggy gas field, so as to maintain the maximum pipeline transportation volume of the fractured-vuggy gas field.

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