Method, device, equipment and medium for recovering productivity of coal bed gas fracturing sweep well

Abstract

The invention relates to the technical field of coal bed gas development, and discloses a coal bed gas fracturing wave and well productivity recovery method, device, equipment and medium, and the method comprises the following steps: determining a fracturing wave and well and an adjacent fracturing well in a region; determining relevance characteristics between the fracturing wave and well and the adjacent fracturing well, wherein the relevance characteristics comprise the distance between the fracturing wave and well and the adjacent fracturing well, the height relation between the coal top altitude of the fracturing wave and well and the coal top altitude of the fracturing point of the adjacent fracturing well, and the consistency between the fracturing wave and direction and the crack direction; determining the influence degree of fracturing on the immediate vicinity of wellbore based on the relevance characteristics; and based on the influence degree of fracturing on the immediate vicinity of the wellbore, determining the productivity recovery method of the fracturing waves and the well. The productivity recovery method has high pertinence, applicability and operability, the adjacent wells can be prevented from being affected in the measure process, and the measure efficiency and the block recovery efficiency are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of coalbed methane development, and in particular to a method, device, equipment and medium for recovering the productivity of a coalbed methane fracturing well. Background Art

[0002] As coalbed methane development progresses, the existing well spacing will be increased, or inefficient old wells will need to be re-fractured, to address key issues that restrict the overall recovery rate of gas reservoirs, such as low reserve utilization and unbalanced utilization. As the number of infilled wells and renovation of old wells increases, the well spacing will shorten. Fracturing of new wells or re-fracturing of old wells will often affect adjacent wells. After the fracturing is affected, the daily water production of adjacent wells increases, and some wells will experience fracturing sand backflow, resulting in a decrease in daily gas production. After the gas production decreases, it is basically impossible to return to normal production, affecting the overall development effect.

[0003] Restoring the productivity of affected wells requires not only considering how to restore production but also how to restore production without affecting the production of adjacent wells. Currently, methods for restoring the productivity of affected wells include acid cleaning, hydraulic shock, plasma pulse, and secondary fracturing. These methods only describe the characteristics, processes, and parameters of the processes, but do not address specific construction parameter settings for affected wells. These methods are applicable to all reservoir-blocked wells and do not consider whether the measures will affect adjacent wells. Consequently, they lack applicability and specificity.

[0004] Based on this, the existing technology still needs to be improved. Summary of the Invention

[0005] The main purpose of the present invention is to provide a method, device, equipment and medium for recovering the productivity of coalbed methane fracture-affected wells, so as to solve the problem in the prior art of lacking a targeted productivity recovery method for fracture-affected wells.

[0006] According to one aspect of the present invention, a method for recovering the productivity of a coalbed methane fracturing well is provided, comprising:

[0007] Determine the affected wells and adjacent fracturing wells in the area;

[0008] Determining correlation characteristics between the affected well and the adjacent fractured well, wherein the correlation characteristics include: the distance between the affected well and the adjacent fractured well, the elevation relationship between the coal top elevation of the affected well and the coal top elevation of the fracture point of the adjacent fractured well, and the consistency between the affected direction of the fracture and the fracture direction of the adjacent fractured well determined based on the azimuth relationship between the affected well and the adjacent fractured well;

[0009] Determining the impact of hydraulic fracturing on the near-wellbore area based on the correlation characteristics;

[0010] Based on the degree of impact of fracturing on the area near the wellbore, a method for recovering the productivity of the well affected by the fracturing is determined.

[0011] According to one embodiment of the present invention, the step of determining the affected wells in the fracturing region includes:

[0012] Determine a gas production decline well in the area, and obtain fracturing construction data of adjacent fracturing wells of the gas production decline well and production data of the gas production decline well;

[0013] Based on the fracturing construction data of the adjacent fracturing wells and the production data of the gas production decline wells, fracturing affected wells are determined from the gas production decline wells.

[0014] According to one embodiment of the present invention, the fracturing operation data includes fracturing operation pressure and fracturing time; the production data includes bottom hole flowing pressure, gas production, and water production; and determining the fracturing affected wells from the gas production decline wells includes: determining the gas production decline wells that meet any of the following conditions as fracturing affected wells:

[0015] The fracturing pressure of the adjacent fracturing well suddenly drops or the fracturing pressure of the adjacent fracturing well is lower than the fracturing pressure of the surrounding wells, and the gas production of the gas production well decreases during the fracturing process of the adjacent fracturing well;

[0016] There is no abnormality in the fracturing construction pressure of the adjacent fracturing wells. The well with gas production decline experiences a rebound in bottom hole flow pressure, an increase in water production, and a decrease in gas production during or after fracturing of the adjacent fracturing wells.

[0017] According to one embodiment of the present invention, determining the impact of fracturing on the near-wellbore area based on the correlation feature includes:

[0018] When the distance between the fracturing affected well and the adjacent fracturing well is smaller, the coal top elevation of the fracturing affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and there is consistency between the fracturing affected direction and the crack direction, it is determined that the impact of fracturing on the near-well area is greater.

[0019] According to one embodiment of the present invention, determining the impact of fracturing on the near-wellbore area based on the correlation feature includes:

[0020] For the following situations, the impact level is classified as Level I:

[0021] The distance between the affected well and the adjacent fracturing well is less than or equal to a first predetermined value, the coal top elevation of the affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the affected direction of the fracturing is consistent with the direction of the crack;

[0022] For any of the following situations, the impact level is classified as Level II:

[0023] The distance between the fracturing affected well and the adjacent fracturing well is less than or equal to the first predetermined value, the coal top elevation of the fracturing affected well is higher than the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is consistent with the crack direction;

[0024] The distance between the affected well and the adjacent fracturing well is less than or equal to the first predetermined value, the coal top elevation of the affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the affected direction of the fracturing is inconsistent with the direction of the crack;

[0025] The distance between the affected well and the adjacent fracturing well is between the first predetermined value and the second predetermined value, the coal top elevation of the affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the affected direction of the fracturing is consistent with the direction of the fracture;

[0026] For any of the following situations, the impact level is classified as Level III:

[0027] The distance between the fracturing affected well and the adjacent fracturing well is between the first predetermined value and the second predetermined value, the coal top elevation of the fracturing affected well is higher than the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is consistent with the fracture direction;

[0028] The distance between the affected well and the adjacent fracturing well is between the first predetermined value and the second predetermined value, the coal top elevation of the affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the affected direction of the fracturing is inconsistent with the direction of the fracture;

[0029] For any of the following situations, the impact level is classified as Level IV:

[0030] The distance between the fracturing affected well and the adjacent fracturing well is between the first predetermined value and the second predetermined value, the coal top elevation of the fracturing affected well is higher than the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is inconsistent with the fracture direction;

[0031] The distance between the affected well and the adjacent fracturing well is greater than or equal to the second predetermined value, the coal top elevation of the affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the affected direction of the fracturing is consistent with the direction of the crack;

[0032] For any of the following situations, the impact level is classified as Level V:

[0033] The distance between the fracturing affected well and the adjacent fracturing well is greater than or equal to the second predetermined value, the coal top elevation of the fracturing affected well is higher than the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is consistent with the crack direction;

[0034] The distance between the affected well and the adjacent fracturing well is greater than or equal to the second predetermined value, the coal top elevation of the affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the affected direction of the fracturing is inconsistent with the direction of the crack;

[0035] For the following situations, the impact level is classified as Level VI:

[0036] The distance between the fracturing affected well and the adjacent fracturing well is greater than or equal to a second predetermined value, the coal top elevation of the fracturing affected well is higher than the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is inconsistent with the crack direction;

[0037] Among them, the lower the level of impact, the greater the impact.

[0038] According to one embodiment of the present invention, the method for determining the productivity recovery of the affected wells based on the impact of the fracturing on the near-wellbore area includes:

[0039] The fluid volume and displacement of the fracturing operation in the affected well are determined based on the impact degree, and when the impact degree is greater, the fluid volume and displacement of the fracturing operation in the affected well are smaller.

[0040] According to one embodiment of the present invention, the method for determining the productivity recovery of the affected wells based on the impact of the fracturing on the near-wellbore area includes:

[0041] When the impact level is classified as level I, the liquid volume and displacement of the fracturing operation of the affected well are determined to be the first liquid volume level and the first displacement level respectively;

[0042] When the impact level is classified as level II, the fluid volume and displacement of the fracturing operation of the affected well are determined to be the second fluid volume level and the first displacement level respectively;

[0043] When the impact level is classified as level III, the fluid volume and displacement of the fracturing operation of the affected well are determined to be the third fluid volume level and the second displacement level respectively;

[0044] When the impact level is classified as level IV, the liquid volume and displacement of the fracturing operation of the affected well are determined to be the fourth liquid volume level and the second displacement level respectively;

[0045] When the impact level is classified as level V, the liquid volume and displacement of the fracturing operation of the affected well are determined to be the fifth liquid volume level and the third displacement level respectively;

[0046] When the impact level is classified as level VI, the fluid volume and displacement of the fracturing operation of the affected well are determined to be level 5 fluid volume and level 4 displacement, respectively;

[0047] Among them, the higher the level of liquid volume and displacement, the larger the values ​​of liquid volume and displacement.

[0048] According to one embodiment of the present invention, the first predetermined value is 100 meters, the second predetermined value is 200 meters; and / or the first liquid volume level is 100 cubic meters, the second liquid volume level is 100-150 cubic meters, the third liquid volume level is 150-200 cubic meters, the fourth liquid volume level is 200-250 cubic meters, and the fifth liquid volume level is 250-300 cubic meters; and / or the first displacement level is 1-1.5 cubic meters / minute, the second displacement level is 1.5-2 cubic meters / minute, the third displacement level is 2-3 cubic meters / minute, and the fourth displacement level is 3-3.5 cubic meters / minute.

[0049] According to another aspect of the present invention, a device for recovering productivity of a coalbed methane fracturing well is provided, comprising:

[0050] A first module is configured to determine a fracture-affected well and its adjacent fracture wells within a region;

[0051] A second module is configured to determine correlation features between the affected well and the adjacent fractured well, wherein the correlation features include: a distance between the affected well and the adjacent fractured well, a height relationship between the coal top elevation of the affected well and the coal top elevation of the fracture point of the adjacent fractured well, and a consistency between a fracture direction determined based on the azimuth relationship between the affected well and the adjacent fractured well and a fracture direction of the adjacent fractured well;

[0052] A third module is configured to determine the impact of the fracturing on the near-wellbore area based on the correlation feature;

[0053] The fourth module is configured to determine a method for restoring the productivity of the wells affected by the fracturing based on the degree of impact of the fracturing on the near-wellbore area.

[0054] According to another aspect of the present invention, a computer device is provided, comprising:

[0055] at least one processor; and

[0056] A memory storing a computer program that can be run on the processor, wherein the processor implements the method described in any of the above embodiments when executing the program.

[0057] According to another aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the method described in any one of the above embodiments is implemented.

[0058] In the technical solution of the present invention, the degree of influence of fracturing on the near-wellbore area is evaluated based on the correlation characteristics between the fracturing-affected wells and the adjacent fracturing wells, and the corresponding production capacity recovery method is determined based on the degree of influence of fracturing on the near-wellbore area. It has strong pertinence, applicability and operability, can avoid the adjacent wells from being affected during the measure process, improve the efficiency of the measure, and is of great significance to improving the overall recovery rate of the block. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0060] Figure 1 A flow chart showing a method for recovering productivity of a coalbed methane fracturing well according to an embodiment of the present invention;

[0061] Figure 2 A schematic diagram of a coalbed methane fracturing well productivity recovery device according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0062] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0063] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. Subsequent embodiments will not explain this one by one.

[0064] Figure 1 FIG. 1 is a flow chart showing a method for recovering the productivity of a coalbed methane fracturing well according to an embodiment of the present invention. Figure 1 As shown, the method includes the following steps:

[0065] S1, determine the affected wells and adjacent fracturing wells in the area;

[0066] S2, determining correlation characteristics between the affected well and the adjacent fractured well, wherein the correlation characteristics include: the distance between the affected well and the adjacent fractured well, the elevation relationship between the coal top elevation of the affected well and the coal top elevation of the fracture point of the adjacent fractured well, and the consistency between the affected direction determined based on the azimuth relationship between the affected well and the adjacent fractured well and the fracture direction of the adjacent fractured well;

[0067] S3, determining the impact of the hydraulic fracturing on the near-wellbore area based on the correlation characteristics;

[0068] S4, determining a method for restoring the productivity of the affected wells based on the impact of the fracturing on the area near the wellbore.

[0069] In embodiments of the present invention, the impact of fracturing on the near-wellbore zone is evaluated based on the correlation characteristics between the affected well and adjacent fracturing wells, and a corresponding production recovery method is determined based on the impact of fracturing on the near-wellbore zone. This method is highly targeted, applicable, and operational, can avoid affecting adjacent wells during the process, improve the efficiency of the method, and is of great significance for increasing the overall recovery rate of the block. The method of the present invention can be performed manually or through automated means using corresponding programs.

[0070] In embodiments of the present invention, the distance between a fracturing affected well and an adjacent fracturing well can be calculated using the horizontal and vertical coordinates of the bottom holes of the two wells. The fracturing affected well and the adjacent fracturing well can be projected onto a structural map, and the azimuth relationship between the two wells can be determined from the map. The fracturing affected direction can be the direction from the adjacent fracturing well toward the fracturing affected well. The fracture direction of the adjacent fracturing well can be obtained based on regional single-well fracture monitoring reports and can represent the direction in which the fracture in the adjacent fracturing well extends outward from the fracturing point.

[0071] In some embodiments, the determining of the fracturing impact wells within the region includes:

[0072] Determine a gas production decline well in the area, and obtain fracturing construction data of adjacent fracturing wells of the gas production decline well and production data of the gas production decline well;

[0073] Based on the fracturing construction data of the adjacent fracturing wells and the production data of the gas production decline wells, fracturing affected wells are determined from the gas production decline wells.

[0074] In some embodiments, the fracturing construction data includes fracturing construction pressure and fracturing time; the production data includes: bottom hole flow pressure, gas production, and water production; the determination of fracturing affected wells (i.e., wells whose gas production has decreased due to fracturing of adjacent wells) from the gas production decline wells includes: determining gas production decline wells that meet any of the following conditions as fracturing affected wells: (1) the fracturing construction pressure of the adjacent fracturing well suddenly drops or the fracturing construction pressure of the adjacent fracturing well is lower than the fracturing construction pressure of the surrounding wells, and the gas production of the gas production decline well decreases during the fracturing process of the adjacent fracturing well; (2) the fracturing construction pressure of the adjacent fracturing well is normal, and the bottom hole flow pressure of the gas production decline well rises, the water production increases, and the gas production decreases during or after the fracturing of the adjacent fracturing well (for example, the instantaneous gas production decreases rapidly). In an embodiment of the present invention, the fracturing construction pressure can be obtained through the fracturing curve of a single well. The bottom hole flow pressure can be obtained by reading the bottom hole flow pressure gauge of a single well. Gas production can be daily or instantaneous. Instantaneous gas production can be read using a wellhead flow meter. Water production can be daily. Daily water production can be calculated by measuring the water volume at the outlet with a measuring cup. The formula for calculating daily water production is as follows:

[0075]

[0076] Among them, Q W - Daily water production of a single well (m 3 );Q M - the amount of water measured by the measuring cup (L); t - the time it takes for the measuring cup to measure the water (s).

[0077] In some embodiments, the determination of the degree of impact of fracturing on the near-wellbore area based on the correlation features includes: determining that the degree of impact of fracturing on the near-wellbore area is greater when the distance between the fracturing affected well and the adjacent fracturing well is smaller, the coal top elevation of the fracturing affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and there is consistency between the fracturing affected direction and the fracture direction. The present invention evaluates the degree of impact based on multiple correlation features such as the distance, the height relationship, and the consistency, which can obtain more accurate evaluation results and help to more effectively guide subsequent production capacity recovery methods. When evaluating the degree of impact of fracturing on the near-wellbore area, the distance, the height relationship, and the consistency can have different importance or contribution levels. In addition to using the table shown below for grading, in some feasible embodiments, the evaluation score can be calculated by, for example, weighted averaging and graded according to the evaluation score. Different weights can be set for the distance, the height relationship, and the consistency.

[0078] In some embodiments, determining the impact degree of fracturing on the near-wellbore area based on the correlation feature includes: grading the impact degree according to the following Table 1:

[0079] Table 1: Classification of the impact of fracturing on the near-wellbore area

[0080]

[0081]

[0082] The lower the level of impact, the greater the impact. In some embodiments, the first predetermined value is 100 meters and the second predetermined value is 200 meters. Although the impact level is divided into six levels as described above in some embodiments of the present invention, the present invention is not limited thereto. Those skilled in the art may divide the impact level into more or fewer levels according to actual circumstances, and may also adaptively adjust the actual values ​​of the first and second predetermined values.

[0083] In some embodiments, the method for determining the productivity recovery of the affected wells based on the impact of fracturing on the near-wellbore area includes: determining the liquid volume and displacement of the fracturing construction of the affected wells based on the impact, and when the impact is greater, the liquid volume and displacement of the fracturing construction of the affected wells are smaller, so as to avoid affecting the adjacent wells when the productivity of the affected wells is recovered. During the fracturing construction, a pump truck and a liquid storage tank that meet the corresponding liquid volume and displacement are prepared at the construction site. Use a pump truck to inject clean water into the formation, increase the displacement step by step, and adjust the displacement according to the pump truck fracturing dynamics. If the pump truck pressure is lower than the formation fracture pressure, continue to increase the displacement until the displacement is maximum. After fracturing, use a rapid flowback process, and immediately return the fracturing fluid, and continuously release it, with the goal of returning the most fracturing fluid.

[0084] In some embodiments, the method for determining the productivity recovery of the affected well based on the impact of fracturing on the near-wellbore area includes: determining the fluid volume and displacement of the fracturing operation of the affected well according to Table 2 below:

[0085] Table 2: Classification of fluid volume and displacement selection for fracturing well fracturing operation

[0086]

[0087]

[0088] The higher the level of liquid volume and displacement, the larger the values ​​of the liquid volume and displacement. In some embodiments, the first liquid volume level is 100 cubic meters, the second liquid volume level is 100-150 cubic meters, the third liquid volume level is 150-200 cubic meters, the fourth liquid volume level is 200-250 cubic meters, and the fifth liquid volume level is 250-300 cubic meters; the first displacement level is 1-1.5 cubic meters per minute, the second displacement level is 1.5-2 cubic meters per minute, the third displacement level is 2-3 cubic meters per minute, and the fourth displacement level is 3-3.5 cubic meters per minute. Those skilled in the art can adjust the values ​​or value ranges of each liquid volume level and each arrangement level according to actual conditions.

[0089] In a specific embodiment, the method for recovering the productivity of a coalbed methane fracturing well of the present invention is performed as follows:

[0090] There are 50 wells with declining production in the X well area. It is necessary to take measures to restore the production capacity of the wells affected by the fracturing.

[0091] 1) Obtain the fracturing pressure, fracturing time, and production data for the gas-decreasing well and adjacent wells. Collect fracturing curves for all wells and read the fracturing pressure. Calculate the bottomhole pressure, water production, and instantaneous gas production of the current well based on on-site or automated readings of the gas-decreasing well.

[0092] 2) Determine whether the production decline well is affected by the fracturing spread well. Based on the currently collected data, determine whether the production decline well has any of the following conditions:

[0093] a. When fracturing an adjacent well, the construction pressure suddenly drops or the construction pressure is lower than that of the surrounding wells, and the gas production of the well decreases during the fracturing process of the adjacent well.

[0094] b. There is no abnormality in the construction pressure of the adjacent well. During or after the fracturing of the adjacent well, the bottom hole flow pressure of this well rises, the water production increases, and the instantaneous gas production drops rapidly.

[0095] Through comparative analysis, it was found that 10 wells met the category a condition and 5 wells met the category b condition, as shown in the following table:

[0096] Table 3: Fracturing affected wells

[0097]

[0098]

[0099] 3) Obtain the distance between the fracturing affected well and the fracturing well, and calculate the distance using the horizontal and vertical coordinates of the bottom of the two wells. The specific distance is shown in Table 4:

[0100] Table 4: Distance of the affected wells from the fracking well

[0101]

[0102]

[0103] 4) Obtain the relative height relationship between the affected well and the adjacent well fracturing point. The relative height relationship between the two wells is obtained by the difference in coal top elevation between the affected well and the adjacent well fracturing point. The specific height relationship is shown in Table 5:

[0104] Table 5: Relative height relationship between the fracturing points of the affected wells and adjacent wells

[0105] Serial number hashtag Altitude of the coal top of this well (m) Altitude of coal top at adjacent well fracturing point (m) Relative height relationship 1 X1 222 230 Low 2 X3 225 230 Low 3 X4 210 220 Low 4 X15 239 232 high 5 X17 226 230 Low 6 X18 232 236 Low 7 X20 233 230 high 8 X21 235 233 high 9 X22 226 226 Low 10 X31 233 235 Low 11 X33 210 218 Low 12 X35 215 210 high 13 X36 219 220 Low 14 X40 229 226 high 15 X42 227 224 high

[0106] 5) Determine whether the fracturing impact direction is consistent with the regional fracture direction. Project the affected well and the adjacent well onto the structural map and obtain the orientation relationship between the two wells from the map. Based on the regional single-well fracture monitoring report, obtain the regional fracture orientation and compare whether the fracturing impact direction is consistent with the regional fracture direction. See Table 6 for details:

[0107] Table 6: Fracturing direction and regional crack direction

[0108]

[0109] 6) Evaluate the impact of fracturing. The impact of fracturing on the area near the wellbore is determined based on the distance between the affected well and the adjacent well, the relative height relationship between the fracturing points of the affected well and the adjacent well, and the consistency between the fracturing impact direction and the regional crack direction. The impact of fracturing is shown in Table 7:

[0110] Table 7: Impact of fracturing on the near-wellbore area

[0111] The impact of fracturing on the area near the wellbore hashtag Ⅰ X1 Ⅱ X3, X15, X18, X33, X31 Ⅲ X4, X17, X20, X21, X22 Ⅳ X36, X40 Ⅴ X35, X42

[0112] 7) Develop appropriate production capacity recovery methods based on the impact of fracturing. First, determine the amount of fluid and displacement required for well construction based on the extent of fracturing's impact on the area near the wellbore. Prepare pump trucks and liquid storage tanks that meet the corresponding fluid and displacement requirements at the construction site. Use the pump truck to inject clean water into the formation, gradually increasing the displacement. Adjust the displacement based on the pump truck's fracturing dynamics. If the pump truck pressure is lower than the formation's fracture pressure, continue to increase the displacement until the maximum displacement is reached. After fracturing, use a rapid flowback process, immediately flow back the fracturing fluid, and continuously release the fluid, with the goal of returning the most fracturing fluid. See Table 8 for specific construction fluid volume and displacement selection methods:

[0113] Table 8: Fracturing wave and well fluid volume, displacement determination method

[0114]

[0115] Figure 2A schematic diagram of a coalbed methane fracturing well productivity recovery device 100 according to an embodiment of the present invention is shown. Figure 2 As shown, the apparatus 100 includes:

[0116] The first module 10 is configured to determine the affected wells and adjacent fracture wells in the region;

[0117] The second module 20 is configured to determine correlation characteristics between the affected well and the adjacent fractured well, wherein the correlation characteristics include: the distance between the affected well and the adjacent fractured well, the elevation relationship between the coal top elevation of the affected well and the fracture point coal top elevation of the adjacent fractured well, and the consistency between the fracture direction determined based on the azimuth relationship between the affected well and the adjacent fractured well and the fracture direction of the adjacent fractured well;

[0118] The third module 30 is configured to determine the impact of the fracturing on the near-wellbore area based on the correlation feature;

[0119] The fourth module 40 is configured to determine a method for restoring the productivity of the wells affected by the fracturing based on the degree of impact of the fracturing on the near-wellbore area.

[0120] The present invention further proposes a computer device, comprising: at least one processor; and a memory, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the program, the method described in any of the above embodiments is implemented.

[0121] The present invention further provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the method described in any one of the above embodiments is implemented.

[0122] In summary, the present invention fully considers the characteristics of the fracturing affected wells, and formulates a coalbed methane fracturing affected well productivity recovery method from three aspects: judging the wells in the region whose gas production has decreased due to the fracturing affected by the adjacent wells, evaluating the degree of fracturing affected near-well zones, and appropriate productivity recovery methods. It has strong pertinence, applicability and operability, can avoid the adjacent wells from being affected during the measures, improves the efficiency of the measures, and is of great significance to improving the overall recovery rate of the block. The coalbed methane fracturing affected well productivity recovery method provided by the present invention can achieve single well production recovery without affecting adjacent wells, thereby improving the efficiency of the measures and the recovery rate of the block. In the technical solution of the present invention, based on the construction pressure, production data, well spacing, relative height and impact direction of the fracturing affected wells and the fracturing wells, the degree of fracturing affected near-well zones is obtained as I-VI. According to the degree of fracturing affected near-well zones, appropriate displacement and fracturing are formulated, and production recovery fracturing construction is performed on the fracturing affected wells, achieving the purpose of not affecting the production of adjacent wells and restoring the productivity of the fracturing affected wells.

[0123] It should be noted that a person skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods.

[0124] Furthermore, it should be appreciated that the computer-readable storage media (eg, memory) herein can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory.

[0125] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples. Within the spirit of the embodiments of the present invention, the technical features of the above embodiments or different embodiments may be combined, and there are many other variations of the different aspects of the embodiments of the present invention described above, which are not provided in detail for the sake of clarity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included within the scope of protection of the embodiments of the present invention.

Claims

1. A method for recovering the productivity of a coalbed methane fracturing affected well, characterized in that: include: Determine the affected wells and adjacent fracturing wells in the area; Determining correlation characteristics between the affected well and the adjacent fractured well, wherein the correlation characteristics include: the distance between the affected well and the adjacent fractured well, the elevation relationship between the coal top elevation of the affected well and the coal top elevation of the fracture point of the adjacent fractured well, and the consistency between the affected direction of the fracture and the fracture direction of the adjacent fractured well determined based on the azimuth relationship between the affected well and the adjacent fractured well; Determining the impact of hydraulic fracturing on the near-wellbore area based on the correlation characteristics; Based on the degree of impact of fracturing on the area near the wellbore, a method for recovering the productivity of the well affected by the fracturing is determined.

2. The method according to claim 1, characterized in that The fracturing affected wells in the determined area include: Determine a gas production decline well in the area, and obtain fracturing construction data of adjacent fracturing wells of the gas production decline well and production data of the gas production decline well; Based on the fracturing construction data of the adjacent fracturing wells and the production data of the gas production decline wells, fracturing affected wells are determined from the gas production decline wells.

3. The method according to claim 2, characterized in that The fracturing operation data includes fracturing operation pressure and fracturing time; the production data includes bottom hole flowing pressure, gas production, and water production; and determining the fracturing affected wells from the gas production decline wells includes: determining the gas production decline wells that meet any of the following conditions as fracturing affected wells: The fracturing pressure of the adjacent fracturing well suddenly drops or the fracturing pressure of the adjacent fracturing well is lower than the fracturing pressure of the surrounding wells, and the gas production of the gas production well decreases during the fracturing process of the adjacent fracturing well; There is no abnormality in the fracturing construction pressure of the adjacent fracturing wells. The well with gas production decline experiences a rebound in bottom hole flow pressure, an increase in water production, and a decrease in gas production during or after fracturing of the adjacent fracturing wells.

4. The method according to claim 1, wherein Determining the impact of hydraulic fracturing on the near-wellbore area based on the correlation characteristics includes: When the distance between the fracturing affected well and the adjacent fracturing well is smaller, the coal top elevation of the fracturing affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and there is consistency between the fracturing affected direction and the crack direction, it is determined that the impact of fracturing on the near-well area is greater.

5. The method according to claim 4, characterized in that Determining the impact of hydraulic fracturing on the near-wellbore area based on the correlation characteristics includes: For the following situations, the impact level is classified as Level I: The distance between the affected well and the adjacent fracturing well is less than or equal to a first predetermined value, the coal top elevation of the affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the affected direction of the fracturing is consistent with the direction of the crack; For any of the following situations, the impact level is classified as Level II: The distance between the fracturing affected well and the adjacent fracturing well is less than or equal to the first predetermined value, the coal top elevation of the fracturing affected well is higher than the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is consistent with the crack direction; The distance between the affected well and the adjacent fracturing well is less than or equal to the first predetermined value, the coal top elevation of the affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the affected direction of the fracturing is inconsistent with the direction of the crack; The distance between the affected well and the adjacent fracturing well is between the first predetermined value and the second predetermined value, the coal top elevation of the affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the affected direction of the fracturing is consistent with the direction of the fracture; For any of the following situations, the impact level is classified as Level III: The distance between the fracturing affected well and the adjacent fracturing well is between the first predetermined value and the second predetermined value, the coal top elevation of the fracturing affected well is higher than the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is consistent with the fracture direction; The distance between the fracturing affected well and the adjacent fracturing well is between the first predetermined value and the second predetermined value, the coal top elevation of the fracturing affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is inconsistent with the fracture direction; For any of the following situations, the impact level is classified as Level IV: The distance between the fracturing affected well and the adjacent fracturing well is between the first predetermined value and the second predetermined value, the coal top elevation of the fracturing affected well is higher than the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is inconsistent with the fracture direction; The distance between the fracturing affected well and the adjacent fracturing well is greater than or equal to the second predetermined value, the coal top elevation of the fracturing affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is consistent with the crack direction; For any of the following situations, the impact level is classified as Level V: The distance between the fracturing affected well and the adjacent fracturing well is greater than or equal to the second predetermined value, the coal top elevation of the fracturing affected well is higher than the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is consistent with the crack direction; The distance between the affected well and the adjacent fracturing well is greater than or equal to the second predetermined value, the coal top elevation of the affected well is lower than or equal to the coal top elevation of the fracturing point of the adjacent fracturing well, and the affected direction of the fracturing is inconsistent with the direction of the crack; For the following situations, the impact level is classified as Level VI: The distance between the fracturing affected well and the adjacent fracturing well is greater than or equal to a second predetermined value, the coal top elevation of the fracturing affected well is higher than the coal top elevation of the fracturing point of the adjacent fracturing well, and the fracturing affected direction is inconsistent with the crack direction; Among them, the lower the level of impact, the greater the impact.

6. The method according to claim 4, characterized in that The method for determining the productivity recovery of the well affected by the fracturing based on the degree of impact of the fracturing on the near-wellbore area includes: The fluid volume and displacement of the fracturing operation in the affected well are determined based on the impact degree, and when the impact degree is greater, the fluid volume and displacement of the fracturing operation in the affected well are smaller.

7. The method according to claim 5, characterized in that The method for determining the productivity recovery of the well affected by the fracturing based on the degree of impact of the fracturing on the near-wellbore area includes: When the impact level is classified as level I, the liquid volume and displacement of the fracturing operation of the affected well are determined to be the first liquid volume level and the first displacement level respectively; When the impact level is classified as level II, the fluid volume and displacement of the fracturing operation of the affected well are determined to be the second fluid volume level and the first displacement level respectively; When the impact level is classified as level III, the fluid volume and displacement of the fracturing operation of the affected well are determined to be the third fluid volume level and the second displacement level respectively; When the impact level is classified as level IV, the liquid volume and displacement of the fracturing operation of the affected well are determined to be the fourth liquid volume level and the second displacement level respectively; When the impact level is classified as level V, the liquid volume and displacement of the fracturing operation of the affected well are determined to be the fifth liquid volume level and the third displacement level respectively; When the impact level is classified as level VI, the liquid volume and displacement of the fracturing operation of the affected well are determined to be the fifth liquid volume level and the fourth displacement level respectively; Among them, the higher the level of liquid volume and displacement, the larger the values ​​of liquid volume and displacement.

8. The method according to claim 7, characterized in that The first predetermined value is 100 meters, the second predetermined value is 200 meters; and / or the first liquid volume level is 100 cubic meters, the second liquid volume level is 100-150 cubic meters, the third liquid volume level is 150-200 cubic meters, the fourth liquid volume level is 200-250 cubic meters, and the fifth liquid volume level is 250-300 cubic meters; and / or the first displacement level is 1-1.5 cubic meters / minute, the second displacement level is 1.5-2 cubic meters / minute, the third displacement level is 2-3 cubic meters / minute, and the fourth displacement level is 3-3.5 cubic meters / minute.

9. A coalbed methane fracturing impact well productivity recovery device, characterized in that: include: A first module is configured to determine a fracture-affected well and its adjacent fracture wells within a region; A second module is configured to determine correlation features between the affected well and the adjacent fractured well, wherein the correlation features include: a distance between the affected well and the adjacent fractured well, a height relationship between the coal top elevation of the affected well and the coal top elevation of the fracture point of the adjacent fractured well, and a consistency between a fracture direction determined based on the azimuth relationship between the affected well and the adjacent fractured well and a fracture direction of the adjacent fractured well; A third module is configured to determine the impact of the fracturing on the near-wellbore area based on the correlation feature; The fourth module is configured to determine a method for restoring the productivity of the wells affected by the fracturing based on the degree of impact of the fracturing on the near-wellbore area.

10. A computer device comprising: at least one processor; as well as A memory storing a computer program executable on the processor, wherein the processor implements the method according to any one of claims 1 to 8 when executing the program.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 8 is implemented.

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