Shale oil fracturing recovery device and method

Abstract

The invention discloses a shale oil fracturing recovery device and method. The device comprises an oil extraction machine, an oil extraction device, a fracturing fluid injection system and at least one gap separator set, and the oil extraction end of the oil extraction machine is arranged in a drilling well through the oil extraction device; the fracturing fluid injection system comprises a fracturing fluid input pipe, a pipe section, extending into a drilling well, of the fracturing fluid input pipe is fixedly sleeved with a mining assisting device, and the mining assisting device is used for accelerating mixing of fracturing fluid and shale oil and pushing mixed fluid of the fracturing fluid and the shale oil to move towards the outer side of the drilling well. The mining assisting device is connected with a driving unit for driving the mining assisting device to move along a drilling well; at least one gap separator set is used for being arranged in an inner side well section of the mining assisting device so as to conduct packing and sectioning on a drilling well, and each gap separator set comprises two gap separators which are arranged at the interval of one drilling hole and provided with movable power sources. By means of the shale oil fracturing recovery device and method, efficient development of shale oil resources can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas extraction, and in particular to a shale oil fracturing recovery device and method. Background Art

[0002] Shale oil, a key component of unconventional oil and gas resources, is stored in shale formations. Due to the extremely hard geological structure of shale formations, which resists natural formation of voids, its development is significantly more challenging than conventional oil resources. During shale oil extraction, fracturing technology is commonly used to effectively extract the oil from the shale. This involves injecting large amounts of fracturing fluid into the wellbore through a fracturing device, using hydraulic pressure to expand the formation and create a complex network of fractures, thereby increasing the yield of shale oil.

[0003] However, the existing shale oil extraction technology still has much room for improvement. During the drilling operation, the horizontal section of the well where oil and gas exist is usually fully covered. When the length of the horizontal section is too long, the number of fracturing holes increases, which will cause excessive shale oil outflow during the oil production process. The excessive outflow of shale oil not only increases the difficulty of on-site processing, but also causes waste of shale oil recovery and reduces resource utilization. In addition, the existing fracturing equipment is prone to oil blockage or poor fluidity during the oil production process, which seriously affects the flow transmission efficiency of shale oil, thereby significantly reducing the recovery efficiency of shale oil and increasing the cost of extraction.

[0004] Therefore, there is an urgent need to develop a fracturing device with a high recovery rate for shale oil development to improve shale oil production efficiency, reduce production costs, and achieve efficient development and utilization of shale oil resources. Summary of the Invention

[0005] The purpose of the present invention is to provide a shale oil fracturing recovery device and method to solve the problems of recovery waste and low recovery efficiency in existing shale oil extraction technologies.

[0006] The above-mentioned purpose of the present invention can be achieved by adopting the following technical solutions:

[0007] The present invention provides a shale oil fracturing and recovery device, comprising an oil production machine, an oil production device, a fracturing fluid injection system and at least one group of gap separator groups, the oil production end of the oil production machine is arranged in a wellbore through the oil production device; the fracturing fluid injection system comprises a fracturing fluid inlet pipe, the outer portion of the pipe section of the fracturing fluid inlet pipe extending into the wellbore is fixedly sleeved with a production aid, when the shale oil fracturing and recovery device is in fracturing operation, the production aid is used to accelerate the mixing of fracturing fluid and shale oil; when the shale oil fracturing and recovery device is in recovery operation, the production aid is used to push the mixture of fracturing fluid and shale oil to move outside the wellbore; the production aid is connected to a driving unit for driving it to move along the wellbore; at least one group of the gap separator groups is used to be arranged in the inner well section of the production aid to isolate and segment the wellbore, and the gap separator group comprises two gap separators arranged at a borehole distance apart and having a mobile power source.

[0008] Preferably, the production aid includes a power module, an intermediate transmission assembly and a spiral production aid. Along the extension direction of the fracturing fluid inlet pipe, the intermediate transmission assembly and the spiral production aid are staggered and connected to form a bendable production aid body, and both ends of the production aid body are the intermediate transmission assemblies. The two ends of the production aid body are symmetrically connected to the drive unit through the power module. The intermediate transmission assembly, the spiral production aid and the drive unit are all provided with a channel for the fracturing fluid inlet pipe to pass through.

[0009] Preferably, the drive unit includes: a telescopic sleeve having a cylinder barrel and a piston barrel in sliding connection, the free end of the piston barrel extending radially outward to form an anti-slip baffle, and the cylinder barrel is connected to the power module; a sliding sleeve slidably arranged outside the cylinder barrel; an elastic member, which is sleeved outside the piston barrel, and the two ends of the elastic member respectively abut the sliding sleeve and the anti-slip baffle; a plurality of drive components are evenly distributed along the circumferential direction of the sliding sleeve, and the drive component includes a driving motor, a first connecting rod group, a second connecting rod group and a traveling wheel, one end of the second connecting rod group is hinged to the cylinder barrel, the other end of the second connecting rod group is hinged to the middle of the first connecting rod group, one end of the first connecting rod group is hinged to the sliding sleeve, and the other end of the first connecting rod group is rotatably connected to the traveling wheel, the first connecting rod is fixedly connected to the driving motor, and the output shaft of the driving motor is transmission-connected to the traveling wheel.

[0010] Preferably, the power module includes a transmission member and a power group, the power group is fixedly connected to the free end of the cylinder barrel, and the transmission member is transmission-connected between the power group and the auxiliary mining body.

[0011] Preferably, the intermediate transmission assembly includes: a protective body having an outer telescopic connecting tube and a protective outer tube symmetrically connected to both ends of the outer telescopic connecting tube, one end of the protective outer tube connected to the outer telescopic connecting tube being connected to a first end plate, and the other end of the protective outer tube being connected to a second end plate; a plurality of transmission rod groups uniformly distributed in the protective outer tube along the circumferential direction of the protective body, the transmission rod group including a positioning sleeve and a transmission connecting rod slidably inserted into the positioning sleeve, the positioning sleeve being embedded in the first end plate, the transmission connecting rod having an end close to the second end plate being sleeved with an elastic connecting piece, the other end of the elastic connecting piece being fixedly connected to the second end plate, and the plurality of transmission rod groups in the two protective outer tubes being correspondingly transmission-connected via the transmission connecting rods; the intermediate transmission assembly located in the middle of the auxiliary procurement body is fixedly embedded between the two spiral auxiliary procurement members through the protective outer tube; the intermediate transmission assemblies located at both ends of the auxiliary procurement body are rotationally connected to the transmission member through one of the protective outer tubes, and are fixedly embedded with the spiral auxiliary procurement member through the other protective outer tube.

[0012] Preferably, the intermediate transmission assembly further comprises a protective inner tube coaxially embedded in the protective outer tube, an inner telescopic connecting tube is connected between the protective inner tubes in the two protective outer tubes, and the other end of the protective inner tube is sealed with the second end plate.

[0013] Preferably, the gap separator includes the driving unit, a support member is fixedly connected to the anti-slip baffle, and a sealing airbag is sheathed on the support member.

[0014] The present invention also provides a method for applying the above-mentioned shale oil fracturing and recovery device, comprising: placing at least one group of gap separator groups in a well and isolating and segmenting the well; after the isolation and segmentation are completed, placing a production aid in the well; starting a power group to enable the production aid to enter the production aid operation; performing a fluid injection fracturing operation on the bottom of the well through a fracturing fluid inlet pipe; and performing a shale oil recovery operation through an oil production machine.

[0015] Preferably, starting the power group to enable the production aid to enter the production aid operation includes: when the shale oil fracturing and recovery device is in the fracturing operation, rotating the power group in a first direction so that the spiral production aid pushes the injection fluid along the internal direction of the drilling well; when the shale oil fracturing and recovery device is in the recovery operation, rotating the power group in a second direction so that the spiral production aid pushes the shale oil along the external direction of the drilling well.

[0016] Preferably, when the shale oil production in the current isolation segment shows a downward trend, after at least one group of the gap separator groups is unsealed, at least one group of the gap separator groups and the production aid are moved to the inside of the well by a distance of a borehole, and the production aid operation, hydraulic fracturing operation and shale oil recovery operation are repeated, and this process is repeated until the oil production work of the entire drilling well is completed.

[0017] The characteristics and advantages of the present invention are:

[0018] The shale oil fracturing and recovery device provided by the present invention realizes the segmented recovery of shale oil in the well by setting a gap separator group, thereby avoiding the waste caused by the large-scale outflow of shale oil; and by setting a production aid to improve the problems of oil blockage or poor fluidity, thereby increasing the recovery rate of shale oil. The present invention can realize the efficient development of shale oil resources.

[0019] The method provided by the present invention for use in a shale oil fracturing and recovery device utilizes the shale oil fracturing and recovery device to recover shale oil, thereby enabling stable and efficient recovery of shale oil in a well. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. 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 creative work.

[0021] Figure 1 A schematic diagram of the composition of a shale oil fracturing and recovery device provided in an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the operating state of the shale oil fracturing recovery device provided in an embodiment of the present invention;

[0023] Figure 3 This is a connection diagram of the extraction aid provided in an embodiment of the present invention;

[0024] Figure 4 A schematic structural diagram of a driving unit provided in an embodiment of the present invention;

[0025] Figure 5 This is a schematic diagram of the connection of the power module provided in an embodiment of the present invention;

[0026] Figure 6 A schematic structural diagram of an intermediate transmission assembly provided in an embodiment of the present invention;

[0027] Figure 7 Schematic diagram of the structure of the gap separator provided in an embodiment of the present invention.

[0028] Description of Figure Numbers:

[0029] 1. Oil production machine;

[0030] 2. Oil extraction device;

[0031] 3. Fracturing fluid inlet pipe;

[0032] 4. Mining aid; 41. Power module; 411. Transmission member; 412. Power group; 42. Intermediate transmission assembly; 421. External telescopic connecting pipe; 422. Protective outer tube; 423. First end plate; 424. Second end plate; 425. Positioning sleeve; 426. Transmission connecting rod; 427. Elastic connector; 428. Protective inner tube; 429. Liquid-proof assembly; 43. Spiral mining aid;

[0033] 5. Drive unit; 51. Telescopic sleeve; 511. Cylinder; 512. Piston; 52. Sliding sleeve; 53. Elastic member; 54. Drive assembly; 541. Drive motor; 542. First connecting rod group; 543. Second connecting rod group; 544. Travel wheel;

[0034] 6. Gap separator; 61. Support member; 62. Blocking airbag;

[0035] 7. Fracturing fluid mixing tank;

[0036] 8. Fracturing fluid booster;

[0037] 9. Oil separator. DETAILED DESCRIPTION

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] like Figures 1 to 7As shown, the present invention provides a shale oil fracturing recovery device, including an oil production machine 1, an oil production device 2, a fracturing fluid injection system and at least one group of gap separators 6. The oil production end of the oil production machine 1 is arranged in a well through the oil production device 2; the fracturing fluid injection system includes a fracturing fluid input pipe 3, and the outer portion of the pipe section of the fracturing fluid input pipe 3 extending into the well is fixedly sleeved with a production aid 4. When the shale oil fracturing recovery device is in a fracturing operation, the production aid 4 is used to accelerate the mixing of the fracturing fluid and the shale oil. When the shale oil fracturing recovery device is in a recovery operation, the production aid 4 is used to promote the mixing of the fracturing fluid and the shale oil. The mixed liquid moves toward the outside of the wellbore to improve oil blockage or poor fluidity and increase the recovery rate of shale oil. The production aid 4 is connected to a drive unit 5 for driving it along the wellbore to achieve movement of the production aid 4 and the fracturing fluid inlet pipe 3 within the wellbore. At least one set of gap dividers 6 is used to be set in the inner well section of the production aid 4 to isolate and segment the wellbore. The gap divider 6 group includes two gap dividers 6 arranged at a distance from the borehole and having a mobile power source to achieve segmented recovery of shale oil and avoid waste caused by large-scale shale oil outflow. Preferably, the production aid 4 is fixedly sleeved on the fracturing fluid inlet pipe 3 via a pipe holder set inside the drive unit 5. In this way, under the drive of the drive unit 5, the output end of the fracturing fluid inlet pipe 3 can move with the production aid 4, further improving the recovery efficiency. In this embodiment, the mobile power source of the gap dividers 6 is the same as the drive unit 5 that drives the production aid 4 along the wellbore.

[0040] Among them, such as Figure 1 As shown, the fracturing fluid injection system also includes a fracturing fluid mixing tank 7 and a fracturing fluid booster 8, which are connected to the input end of the fracturing fluid inlet pipe 3. An oil pipeline is provided inside the oil extraction unit 2, the input end of the pipeline being located at the oil extraction end, and the output end of the pipeline being connected to an oil-liquid separator 9. Preferably, the fracturing fluid mixing tank 7 is provided with a fracturing fluid storage chamber and a proppant storage chamber.

[0041] Preferably, the shale oil fracturing recovery device also includes a ground control system, which is used to perform ground control on at least the oil extractor 2, the drive unit 5, and the slit separator 6 to achieve efficient recovery of shale oil in the entire well.

[0042] Preferably, the shale oil fracturing recovery device includes multiple groups of slit separators 6, which are spaced apart along the inner side of the wellbore, with the interval between two adjacent slit separators 6 being at most one borehole distance. This ensures that if a slit separator 6 fails, the adjacent slit separator 6 can be quickly moved and replaced. This ensures that the isolation segments within the wellbore remain effective during the shale oil staged recovery process, preventing large-scale shale oil outflow, thereby achieving stable shale oil recovery. As a preferred embodiment, the distance between each borehole is 20m to 30m.

[0043] The shale oil fracturing and recovery device provided by the present invention realizes the segmented recovery of shale oil in the well by setting up 6 groups of gap separators, thereby avoiding the waste caused by the large-scale outflow of shale oil; and by setting up a production aid 4, it improves the problems of oil blockage or poor fluidity, thereby increasing the recovery rate of shale oil. The present invention can realize the efficient development of shale oil resources.

[0044] According to one embodiment of the present invention, Figure 3 and Figure 5 As shown, the production aid 4 comprises a power module 41, an intermediate transmission assembly 42, and a spiral production aid 43. Along the extension of the fracturing fluid inlet pipe 3, the intermediate transmission assembly 42 and the spiral production aid 43 are interlaced to form a flexible production aid body. This allows the production aid body to adapt to complex wellbore trajectories and facilitates the movement of bottomhole oil toward the wellhead during the vertical climb curve of the drilling process. Furthermore, both ends of the production aid body are connected symmetrically to the drive unit 5 via the power module 41, thereby enhancing the stability and reliability of the production aid 4. By controlling the rotation direction of the two power modules 41, the production aid body's delivery direction can be controlled. This allows the production aid body to deliver fracturing fluid to the inside of the wellbore during fracturing fluid injection, reducing injection and fracturing time. It also acts as a stirring mechanism, rapidly and thoroughly mixing the fracturing fluid with the shale oil, preventing shale oil blockage and improving shale oil fluidity. Furthermore, the production aid body can deliver a mixture of fracturing fluid and shale oil to the outside of the wellbore during oil recovery, improving recovery efficiency. The intermediate transmission assembly 42 , the spiral production aid 43 , and the drive unit 5 are all provided with a passage for the fracturing fluid input pipe 3 to pass through.

[0045] As a preferred embodiment, when the mining aid 4 is driven to move along the borehole, the ground control system activates the drive units 5 at both ends of the mining aid 4. By controlling the drive output directions of the two drive units 5, the drive unit 5 at the front end of the movement direction applies a pulling force to the mining aid 4, while the drive unit 5 at the rear end of the movement direction applies a pushing force to the mining aid 4, thereby quickly moving the mining aid 4 to the target position. Of course, it is also possible to activate only one of the drive units 5 to move the mining aid 4, while the other is kept in reserve, and this is not limited to this application.

[0046] According to one embodiment of the present invention, Figure 4As shown, the drive unit 5 includes a telescopic sleeve 51, a sliding sleeve 52, an elastic member 53 and a plurality of drive assemblies 54. The telescopic sleeve 51 has a cylinder barrel 511 and a piston barrel 512 that are slidably connected. The free end of the piston barrel 512 extends radially outward to form an anti-slip baffle. The cylinder barrel 511 is connected to the power module 41; the sliding sleeve 52 is slidably sleeved on the outside of the cylinder barrel 511; the elastic member 53 is sleeved on the outside of the piston barrel 512, and the two ends of the elastic member 53 respectively abut the sliding sleeve 52 and the anti-slip baffle; the plurality of drive assemblies 54 are arranged along the sliding sleeve 52. Uniformly distributed along the circumference, the drive assembly 54 includes a drive motor 541, a first connecting rod assembly 542, a second connecting rod assembly 543, and travel wheels 544. One end of the second connecting rod assembly 543 is hinged to the cylinder barrel 511, and the other end of the second connecting rod assembly 543 is hinged to the middle of the first connecting rod assembly 542. One end of the first connecting rod assembly 542 is hinged to the sliding sleeve 52, and the other end of the first connecting rod assembly 542 is rotatably connected to the travel wheels 544. The first connecting rod is fixedly connected to the drive motor 541, and the output shaft of the drive motor 541 is transmission-connected to the travel wheels 544. In this way, the drive unit 5 located in the well contacts the well wall via the multiple travel wheels 544, ensuring that the telescopic sleeve 51 is always on the well centerline. This in turn limits the position of the extraction aid 4 relative to the wellbore, preventing collision between the extraction aid 4 and the well wall, thereby ensuring the extraction efficiency and service life of the extraction aid 4. By extending and retracting the telescopic sleeve 51, the distance between the traveling wheel 544 and the center line of the well can be changed, so that the drive unit 5 can move in wells of different diameters, so that the production aid 4 can adapt to the production work of wells of different diameters. Driven by each drive motor 541, multiple traveling wheels 544 move along the well wall, driving the production aid 4 and the fracturing fluid input pipe 3 to move along the inside of the well, facilitating the recovery of shale oil in the entire well. As a preferred embodiment, the drive unit 5 includes three drive assemblies 54 arranged at intervals of 120° along the circumferential direction of the sliding sleeve 52, so that the drive unit 5 can always be stably supported on the center line of the well through the three traveling wheels 544, thereby ensuring that the drive unit 5 can obtain better driving stability. Preferably, the elastic member 53 is a spring.

[0047] According to one embodiment of the present invention, Figure 5 As shown, power module 41 includes a transmission member 411 and a power pack 412. Power pack 412 is fixedly connected to the free end of cylinder barrel 511. Transmission member 411 is drivingly connected between power pack 412 and the main body of the extraction aid. Exemplarily, transmission member 411 is a drive pulley that meshes with power pack 412 and is rotationally connected to intermediate transmission assembly 42 at the end of the main body of the extraction aid, thereby transmitting power to the rotation of the main body.

[0048] According to one embodiment of the present invention, Figure 6As shown, the intermediate transmission assembly 42 includes a protective body and multiple transmission rod groups. The protective body has an outer telescopic connecting tube 421 and a protective outer tube 422 symmetrically connected to both ends of the outer telescopic connecting tube 421. One end of the protective outer tube 422 connected to the outer telescopic connecting tube 421 is connected to a first end plate 423, and the other end of the protective outer tube 422 is connected to a second end plate 424; multiple transmission rod groups are evenly distributed in the protective outer tube 422 along the circumferential direction of the protective body. The transmission rod group includes a positioning sleeve 425 and a transmission connecting rod 426 that slides through the positioning sleeve 425. The positioning sleeve 425 is embedded in the first end plate 423. 3, a transmission link 426 is sleeved with an elastic connector 427 at one end near the second end plate 424, and the other end of the elastic connector 427 is fixedly connected to the second end plate 424. Multiple transmission rod groups within the two protective outer tubes 422 are correspondingly connected through the transmission link 426. The intermediate transmission assembly 42, located in the middle of the auxiliary body, is fixedly engaged between the two spiral auxiliary members 43 via the protective outer tube 422. The intermediate transmission assemblies 42, located at both ends of the auxiliary body, are rotationally connected to the transmission member 411 via one of the protective outer tubes 422 and fixedly engaged with the spiral auxiliary member 43 via the other protective outer tube 422. Thus, the intermediate transmission assembly 42 forms a universal joint system, where the sliding movement of the transmission link 426 relative to the positioning sleeve 425 offsets changes in the diameter of the protective outer tube 422. The elastic connector 427, which uses elastic force to force the two interconnected transmission links 426 to extend the same distance, thus ensuring the universal joint system is implemented. The elastic connector 427 also assists in resetting the transmission links 426. Preferably, the elastic connecting member 427 is a spring.

[0049] According to one embodiment of the present invention, Figure 6 As shown, the intermediate transmission assembly 42 also includes a protective inner tube 428 coaxially embedded within the protective outer tube 422. An inner telescopic connecting tube is connected between the protective inner tubes 428 within the two protective outer tubes 422. The other end of the protective inner tube 428 is sealed with the second end plate 424. A through hole is provided on the first end plate 423 for the protective inner tube 428 to pass through. The protective inner tube 428 and the inner telescopic connecting tube are connected to form an internal passage for the fracturing fluid input pipe 3 to pass through, thereby isolating the fracturing fluid input pipe 3 from the transmission rod assembly to avoid mutual interference. The other end of the protective inner tube 428 is sealed with the second end plate 424 via a liquid-proof assembly 429 to prevent fracturing fluid and shale oil from entering the interior of the intermediate transmission assembly 42, thereby preventing the fracturing fluid and shale oil from corroding the internal components of the intermediate transmission assembly 42, maintaining the stable operation of the production aid 4, and further improving the service life of the production aid 4.

[0050] According to one embodiment of the present invention, Figure 7As shown, the gap separator 6 includes the above-mentioned drive unit 5, a support member 61 fixedly connected to the anti-slip baffle, and a sealing airbag 62 is sheathed on the support member 61. For example, an air supply system consisting of a micro high-pressure gas tank, an electric air pump, an airbag pipeline, a two-way solenoid valve, a pressure sensor and a lithium battery pack is integrated in the internal space of the telescopic sleeve 51 and the support member 61 to provide a sealing air source for the sealing airbag 62. When the gap separator 6 moves to the target position, each drive motor 541 stops and the sealing airbag 62 enters the inflation stage. The ground control system sends an inflation command, starts the electric air pump and opens the air inlet valve of the two-way solenoid valve. The compressed gas in the micro high-pressure gas tank is transported to the sealing airbag 62 through the airbag pipeline, causing the sealing airbag 62 to expand and adhere to the well wall to form a partial blockage. During this process, the pressure sensor monitors the pressure in the sealing airbag 62 in real time. When the preset threshold is reached, the electric air pump and the air inlet valve are turned off, and the sealing airbag 62 remains in a blocked state. When the gap divider 6 needs to be moved, the plugging airbag 62 enters the exhaust phase. The ground control system sends a deflation command, opening the exhaust valve of the two-way solenoid valve. The gas in the plugging airbag 62 is recovered through the exhaust valve to the miniature high-pressure gas tank. After the gas is exhausted for a preset time, the plugging airbag 62 is reset, and the drive motors 541 are activated, pushing the gap divider 6 along the drilling path via the travel wheels 544. The airbag piping, solenoid valve, and lithium battery pack are all designed with sealed protective structures to prevent liquid intrusion and affect performance. As a preferred embodiment, the sealing airbag 62 is made of high-strength rubber composite material with a pressure resistance of ≥20MPa and a temperature resistance of ≥150°C; the micro high-pressure gas tank and the airbag pipeline are made of 316L stainless steel to be suitable for the underground environment, and the sealing gas source stored in the micro high-pressure gas tank is an inert gas; the electric air pump adopts a high-temperature resistant and explosion-proof micro electric air pump; the lithium battery pack adopts a high-capacity and high-temperature resistant lithium battery and is equipped with a thermal management system (such as phase change material heat dissipation) to ensure stable power supply in a high-temperature environment; the ground control system transmits instructions through an anti-interference wireless module and monitors the airbag status and the lithium battery pack power in real time.

[0051] The present invention also provides a method for applying the above-mentioned shale oil fracturing and recovery device, comprising: placing at least one group of gap separators 6 in a well to isolate and segment the well; after the isolation and segmentation are completed, placing a production aid 4 in the well; starting the power group 412 to enable the production aid 4 to enter the production aid operation; performing a fluid injection fracturing operation on the bottom of the well through the fracturing fluid input pipe 3; and performing a shale oil recovery operation through the oil production machine 1.

[0052] Exemplarily, the method applied to the above-mentioned shale oil fracturing recovery device includes:

[0053] Step S0: Through detailed geological exploration and modeling, understand the distribution, thickness, porosity and other characteristics of the shale layer, use this data to formulate an accurate mining plan, ensure the optimization of drilling location and direction, and make drill holes and wells, determine the actual oil production efficiency (maximum oil production area per unit time) based on the actual drilling situation, and formulate an actual oil production plan.

[0054] Step S1: After the ground control system controls at least one group of slot dividers 6 to move to a target location, the ground control system sends an inflation command. The air supply system receives the inflation command and initiates the inflation process, causing the sealing airbags 62 of each slot divider 6 to inflate and seal the current well section. Moving the at least one group of slot dividers 6 to the target location includes positioning one slot divider 6 in the at least one group of slot dividers 6 near the fracturing hole at the maximum oil production area, and positioning the other slot divider 6 further inboard of the wellbore, with a horizontal borehole distance between the two slot dividers 6.

[0055] Step S2: placing the production aid 4 connected with the driving unit 5 and the fracturing fluid inlet pipe 3 in the well.

[0056] Step S3: Start the fracturing fluid injection system, and use the fracturing fluid booster 8 to first inject the fracturing fluid stored in the fracturing fluid storage chamber in the fracturing fluid mixing tank 7 into the bottom of the well through the fracturing fluid inlet pipe 3. The fracturing fluid forms a high-pressure environment at the bottom of the well, which propagates the formation and generates cracks; then, the proppant stored in the proppant storage chamber in the fracturing fluid mixing tank 7 is injected into the cracks through the fracturing fluid inlet pipe 3 to maintain the stability of the cracks.

[0057] Step S4: The ground control system controls the power group 412 to start and control its rotation direction to accelerate the mixing of shale oil and fracturing fluid, and push the mixture of shale oil and fracturing fluid toward the outside of the wellbore, thereby accelerating the recovery of shale oil; at the same time, the shale oil is led out into the wellbore through the oil production end of the oil production machine 1, and introduced into the oil separator 9 through the oil pipeline, thereby achieving the purpose of extraction.

[0058] The method provided by the present invention for use in a shale oil fracturing and recovery device utilizes the shale oil fracturing and recovery device to recover shale oil, thereby enabling stable and efficient recovery of shale oil in a well.

[0059] According to one embodiment of the present invention, activating the power assembly 412 to enable the recovery aid 4 to begin the recovery operation includes: when the shale oil fracturing and recovery device is in the fracturing operation, rotating the power assembly 412 in a first direction to cause the spiral recovery aid 43 to push the injection fluid toward the interior of the wellbore; and when the shale oil fracturing and recovery device is in the recovery operation, rotating the power assembly 412 in a second direction to cause the spiral recovery aid 43 to push the shale oil toward the exterior of the wellbore. For example, when the ground control system controls the power assembly 412 at both ends of the recovery aid body to rotate clockwise at the same speed, the spiral recovery aid 43 pushes the injection fluid toward the interior of the wellbore, accelerating the mixing of the injection fluid and shale oil and reducing the injection and fracturing operation time; when the ground control system controls the power assembly 412 at both ends of the recovery aid body to rotate counterclockwise at the same speed, the spiral recovery aid 43 pushes the mixture of the injection fluid and shale oil toward the exterior of the wellbore, accelerating the extraction and recovery of shale oil and improving shale oil recovery efficiency.

[0060] According to one embodiment of the present invention, when the shale oil production in the current isolation segment shows a downward trend, after at least one group of gap separators 6 is unsealed, at least one group of gap separators 6 and the production aid 4 are moved to the inside of the well by the distance of a borehole, and the production aid operation, hydraulic fracturing operation and shale oil recovery operation are repeated, and this process is repeated until the oil production work of the entire drilling well is completed.

[0061] For example, if the shale oil production in the current isolated segment shows a downward trend, it means that the shale oil in the current isolated segment has been basically recovered. At this time, the ground control system sends a deflation command, the gas supply system receives the deflation command and initiates the deflation process, the plugging airbag 62 deflates and contracts to release the seal, and a release completion signal is fed back to the ground control system. The ground control system then controls the drive unit 5 and the gap dividers 6 of the production aid 4 to start, driving at least one group of gap dividers 6 and the production aid 4 to continue moving inward of the wellbore by the distance of the borehole, repeating the above inflation and plugging process. After the new wellbore segment is plugged, the above-mentioned production aid operation, hydraulic fracturing operation, and shale oil recovery operation are repeated, and this process is repeated until the staged oil production of the entire drilling well is completed. In a preferred embodiment, the ground control system first controls the power group 412 to stop rotating and output before controlling the production aid 4 to continue moving inward of the wellbore, so that the production aid 4 can move smoothly and quickly inward of the wellbore.

[0062] The above descriptions are only several embodiments of the present invention. Those skilled in the art may make various changes or modifications to the embodiments of the present invention based on the contents disclosed in the application documents without departing from the spirit and scope of the present invention.

Claims

1. A shale oil fracturing recovery device, characterized in that: It includes an oil production machine, an oil production device, a fracturing fluid injection system and at least one set of gap separators, wherein the oil production end of the oil production machine is arranged in a well through the oil production device; The fracturing fluid injection system includes a fracturing fluid inlet pipe, a section of the fracturing fluid inlet pipe extending into the well having a production aid fixedly sleeved thereon. When the shale oil fracturing and recovery device is in a fracturing operation, the production aid is used to accelerate the mixing of the fracturing fluid and shale oil; when the shale oil fracturing and recovery device is in a recovery operation, the production aid is used to push the mixture of the fracturing fluid and shale oil toward the outside of the well; the production aid is connected to a drive unit for driving it to move along the well; At least one of the gap separator groups is used to be arranged in the inner well section of the production aid to isolate and segment the well. The gap separator group includes two gap separators arranged at a borehole distance and having a mobile power source.

2. The shale oil fracturing recovery device according to claim 1, characterized in that: The production aid includes a power module, an intermediate transmission assembly and a spiral production aid. Along the extension direction of the fracturing fluid inlet pipe, the intermediate transmission assembly and the spiral production aid are staggered and connected to form a bendable production aid body, and both ends of the production aid body are the intermediate transmission assemblies. The two ends of the production aid body are symmetrically connected to the drive unit through the power module. The intermediate transmission assembly, the spiral production aid and the drive unit are all provided with a channel for the fracturing fluid inlet pipe to pass through.

3. The shale oil fracturing recovery device according to claim 2, characterized in that: The driving unit includes: A telescopic sleeve having a cylinder barrel and a piston barrel that are slidably connected, wherein the free end of the piston barrel extends radially outward to form an anti-slip baffle, and the power module is connected to the cylinder barrel; A sliding sleeve, which is arranged outside the cylinder; an elastic member, sleeved on the outside of the piston cylinder, with two ends of the elastic member respectively abutting against the sliding sleeve and the anti-slip baffle; Multiple drive components are evenly distributed along the circumferential direction of the sliding sleeve, and the drive components include a drive motor, a first connecting rod group, a second connecting rod group and a traveling wheel. One end of the second connecting rod group is hinged to the cylinder barrel, and the other end of the second connecting rod group is hinged to the middle part of the first connecting rod group. One end of the first connecting rod group is hinged to the sliding sleeve, and the other end of the first connecting rod group is rotatably connected to the traveling wheel. The drive motor is fixedly connected to the first connecting rod, and the output shaft of the drive motor is transmission-connected to the traveling wheel.

4. The shale oil fracturing recovery device according to claim 3, characterized in that: The power module includes a transmission member and a power group. The power group is fixedly connected to the free end of the cylinder barrel. The transmission member is transmission-connected between the power group and the auxiliary mining body.

5. The shale oil fracturing recovery device according to claim 4, characterized in that: The intermediate transmission assembly comprises: The protective body comprises an external telescopic connecting pipe and a protective outer pipe symmetrically connected to both ends of the external telescopic connecting pipe, wherein one end of the protective outer pipe connected to the external telescopic connecting pipe is connected to a first end plate, and the other end of the protective outer pipe is connected to a second end plate; A plurality of transmission rod groups are evenly distributed in the protective outer tube along the circumferential direction of the protective body, the transmission rod group includes a positioning sleeve and a transmission connecting rod slidably inserted into the positioning sleeve, the positioning sleeve is embedded in the first end plate, and the end of the transmission connecting rod close to the second end plate is sleeved with an elastic connector, and the other end of the elastic connector is fixedly connected to the second end plate. The plurality of transmission rod groups in the two protective outer tubes are correspondingly connected through the transmission connecting rods; The intermediate transmission assembly located in the middle of the procurement aid body is fixedly embedded between the two spiral procurement aid parts through the protective outer tube; the intermediate transmission assembly located at both ends of the procurement aid body is rotationally connected to the transmission part through one of the protective outer tubes, and is fixedly embedded with the spiral procurement aid part through the other protective outer tube.

6. The shale oil fracturing recovery device according to claim 5, characterized in that: The intermediate transmission assembly also includes a protective inner tube coaxially embedded in the protective outer tube, an inner telescopic connecting tube is connected between the two protective inner tubes in the protective outer tubes, and the other end of the protective inner tube is sealed with the second end plate.

7. The shale oil fracturing recovery device according to claim 3, characterized in that: The gap separator includes the driving unit, the anti-slip baffle is fixedly connected to a support member, and the support member is sheathed with a blocking airbag.

8. A method for applying the shale oil fracturing recovery device according to any one of claims 1 to 7, characterized in that: include: placing at least one set of seam separators in the wellbore and isolating and segmenting the wellbore; After the isolation and segmentation are completed, the production aid is placed in the borehole; Turning on the power group to enable the mining aid to start the mining aid operation; Perform hydraulic fracturing operations on the bottom of the well through the fracturing fluid input pipe; Shale oil recovery operations are carried out using oil recovery machines.

9. The method of shale oil fracturing recovery device according to claim 8, characterized in that: Turning on the power group to enable the production aid to enter the production aid operation includes: when the shale oil fracturing and recovery device is in the fracturing operation, rotating the power group in a first direction so that the spiral production aid pushes the injection fluid along the direction inside the well; when the shale oil fracturing and recovery device is in the recovery operation, rotating the power group in a second direction so that the spiral production aid pushes the shale oil along the direction outside the well.

10. The method of shale oil fracturing recovery device according to claim 8, characterized in that: When the shale oil production in the current isolation segment shows a downward trend, after at least one group of the gap separator groups is unsealed, at least one group of the gap separator groups and the production aid are moved to the inside of the well by the distance of a borehole, and the production aid operation, hydraulic fracturing operation and shale oil recovery operation are repeated, and this process is repeated until the oil production work of the entire drilling well is completed.

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