Shale oil fracturing recovery apparatus and method

Abstract

The application discloses a shale oil fracturing recovery device and method. The device comprises an oil extraction machine, an oil extractor, a fracturing fluid injection system and at least one set of fracture spacer groups. The oil extraction end of the oil extraction machine is arranged in a well through the oil extractor. The fracturing fluid injection system comprises a fracturing fluid input pipe. An outside fixed sleeve of a pipe section of the fracturing fluid input pipe extending into the well is sleeved with a recovery aid. The recovery aid is used for accelerating the mixing of fracturing fluid and shale oil and for pushing the mixed liquid of the fracturing fluid and the shale oil to move to the outside of the well. A driving unit for driving the recovery aid to move along the well is connected to the recovery aid. At least one set of the fracture spacer groups is arranged in the inside well section of the recovery aid to seal and segment the well. The fracture spacer groups comprise two fracture spacers arranged at an interval of a drilling hole distance and provided with a moving power source. The shale oil fracturing recovery device and method can realize the efficient development of shale oil resources.

Description

Technical Field

[0001] This invention relates to the field of oil and gas extraction technology, and in particular to a shale oil fracturing and recovery device and method. Background Technology

[0002] Shale oil, as an important component of unconventional oil and gas resources, is stored in shale formations. Due to the extremely hard geological structure of shale formations, it is difficult for voids to form naturally, making its development significantly more challenging than that of conventional oil resources. In the process of shale oil extraction, fracturing technology is commonly used to effectively extract oil from the shale. This involves injecting a large amount of hydraulic fluid into the bottom of the well using a fracturing device, utilizing hydraulic force to open up the formation and form a complex network of fractures, thereby increasing the amount of shale oil extracted.

[0003] However, existing shale oil extraction technologies still have many areas for improvement. Current drilling operations typically involve full-coverage drilling of the horizontal sections containing oil and gas. When these horizontal sections are too long, the number of fracturing holes increases, leading to excessive shale oil outflow during production. This excessive outflow not only increases the difficulty of on-site processing but also wastes shale oil recovery time and reduces resource utilization. Furthermore, existing fracturing devices are prone to oil blockage or poor flowability during production, severely impacting shale oil flow and transport efficiency, thus significantly reducing recovery efficiency and increasing extraction costs.

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

[0005] The purpose of this invention is to provide a shale oil fracturing and 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 objectives of the present invention can be achieved by the following technical solutions:

[0007] This invention provides a shale oil fracturing and recovery device, including an oil production machine, an oil production unit, a fracturing fluid injection system, and at least one set of fracture separators. The oil production end of the oil production machine is located inside the well via the oil production unit. The fracturing fluid injection system includes a fracturing fluid input pipe, and an auxiliary production device is fixedly sleeved on the outside of the section of the fracturing fluid input pipe extending into the well. When the shale oil fracturing and recovery device is in fracturing operation, the auxiliary production device 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 auxiliary production device is used to push the mixture of fracturing fluid and shale oil to move outward from the well. A drive unit is connected to the auxiliary production device to drive its movement along the well. At least one set of fracture separators is used to be installed inside the well section of the auxiliary production device to isolate and segment the well. The fracture separator set includes two fracture separators spaced one borehole distance apart and having a moving power source.

[0008] Preferably, the fracturing fluid extraction device includes a power module, an intermediate transmission assembly, and a spiral extraction component. Along the extension direction of the fracturing fluid input pipe, the intermediate transmission assembly and the spiral extraction component are alternately connected to form a flexible extraction body. Both ends of the extraction body are the intermediate transmission assembly. The two ends of the extraction body are symmetrically connected to the drive unit through the power module. The intermediate transmission assembly, the spiral extraction component, and the drive unit are all provided with channels for the fracturing fluid input pipe to pass through.

[0009] Preferably, the drive unit includes: a telescopic sleeve having a cylinder and a piston cylinder slidably connected, the free end of the piston cylinder extending radially outward to form an anti-detachment baffle, and the power module connected to the cylinder; a sliding sleeve slidably sleeved outside the cylinder; an elastic element sleeved outside the piston cylinder, with both ends of the elastic element abutting against the sliding sleeve and the anti-detachment baffle respectively; and multiple drive components evenly distributed along the circumference of the sliding sleeve. Each drive component includes 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, and 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 drive motor is fixedly connected to the first connecting rod, and the output shaft of the drive motor is drively connected to the traveling wheel.

[0010] Preferably, the power module includes a transmission component and a power unit, the power unit is fixedly connected to the free end of the cylinder, and the transmission component is drivingly connected between the power unit and the mining auxiliary body.

[0011] Preferably, the intermediate transmission assembly includes: a protective body having an outer telescopic connecting pipe and protective outer pipes symmetrically connected to both ends of the outer telescopic connecting pipe, one end of the protective outer pipe connected to the outer telescopic connecting pipe being connected to a first end plate, and the other end of the protective outer pipe being connected to a second end plate; multiple transmission rod groups evenly distributed within the protective outer pipes along the circumferential direction of the protective body, each transmission rod group including a positioning sleeve and a transmission connecting rod slidably passing through the positioning sleeve, the positioning sleeve being fitted onto the first end plate, one end of the transmission connecting rod near the second end plate being sleeved with an elastic connecting member, and the other end of the elastic connecting member being fixedly connected to the second end plate; the multiple transmission rod groups within the two protective outer pipes being correspondingly connected via the transmission connecting rods; the intermediate transmission assembly located in the middle of the mining auxiliary body being fixedly embedded between the two spiral mining auxiliary components via the protective outer pipe; and the intermediate transmission assemblies located at both ends of the mining auxiliary body being rotatably connected to the transmission component via one of the protective outer pipes and fixedly embedded to the spiral mining auxiliary component via the other protective outer pipe.

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

[0013] Preferably, the gap separator includes the drive unit, a support member is fixedly connected to the anti-detachment baffle, and a sealing airbag is fitted over the support member.

[0014] The present invention also provides a method for use in the above-mentioned shale oil fracturing and recovery device, comprising: placing at least one set of fracture separators in the well and isolating and segmenting the well; after the isolation and segmentation are completed, placing the production aid in the well; activating the power unit to enable the production aid to enter the production operation; performing hydraulic fracturing operation by injecting hydraulic fluid into the bottom of the well through the fracturing fluid input pipe; and performing shale oil recovery operation by using the oil production machine.

[0015] Preferably, activating the power unit to enable the production aid to enter the production operation includes: when the shale oil fracturing and recovery device is in fracturing operation, rotating the power unit in a first direction to push the injection fluid along the inside of the well; and when the shale oil fracturing and recovery device is in recovery operation, rotating the power unit in a second direction to push the shale oil along the outside of the well.

[0016] Preferably, when the shale oil production in the current sealed section is declining, after at least one set of the fracture separator group is unsealed, at least one set of the fracture separator group and the production aid are moved to the inside of the well by the distance of one borehole, and the production aid operation, hydraulic fracturing operation and shale oil recovery operation are repeated, and so on, until the oil production work of the entire well is completed.

[0017] The features and advantages of this invention are:

[0018] The shale oil fracturing and recovery device provided by this invention enables segmented recovery of shale oil within the well by setting up a fracture separator group, avoiding the waste caused by large-scale shale oil outflow; and by setting up an auxiliary recovery device, it improves the problem of oil blockage or poor fluidity, thereby increasing the shale oil recovery rate. This invention can achieve efficient development of shale oil resources.

[0019] The method for shale oil fracturing and recovery equipment provided by the present invention utilizes the aforementioned shale oil fracturing and recovery equipment to recover shale oil, enabling stable and efficient recovery of shale oil within the well. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the composition of the shale oil fracturing and recovery device provided in the embodiments of the present invention;

[0022] Figure 2 This is a schematic diagram of the operational status of the shale oil fracturing and recovery device provided in the embodiments of the present invention;

[0023] Figure 3 This is a schematic diagram of the connection of the data acquisition aid provided in the embodiment of the present invention;

[0024] Figure 4 This is a schematic diagram of the structure of the driving unit provided in the embodiment of the present invention;

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

[0026] Figure 6 This is a schematic diagram of the intermediate transmission assembly provided in an embodiment of the present invention;

[0027] Figure 7 This is a schematic diagram of the gap separator provided in an embodiment of the present invention.

[0028] Explanation of icon numbers:

[0029] 1. Oil extraction machine;

[0030] 2. Oil pumping unit;

[0031] 3. Fracturing fluid inlet pipe;

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

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

[0034] 6. Gap separator; 61. Support component; 62. Sealing airbag;

[0035] 7. Fracturing fluid mixing tank;

[0036] 8. Fracturing fluid booster;

[0037] 9. Oil separator. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] like Figures 1 to 7As shown, this invention provides a shale oil fracturing and recovery device, including an oil production machine 1, an oil production unit 2, a fracturing fluid injection system, and at least one set of fracture separators 6. The oil production end of the oil production machine 1 is installed inside the well via the oil production unit 2. The fracturing fluid injection system includes a fracturing fluid inlet pipe 3, and an auxiliary production device 4 is fixedly sleeved on the outside of the section of the fracturing fluid inlet pipe 3 that extends into the well. When the shale oil fracturing and recovery device is in fracturing operation, the auxiliary production device 4 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 auxiliary production device 4 is used to promote the mixing of fracturing fluid and shale oil. The mixed fluid moves outward from the wellbore to improve oil blockage or poor flowability, thereby increasing the shale oil recovery rate. The production aid 4 is connected to a drive unit 5 for moving along the wellbore, enabling the movement of the production aid 4 and the fracturing fluid inlet pipe 3 within the wellbore. At least one set of fracture separators 6 is installed within the inner section of the production aid 4 to isolate and segment the wellbore. Each set of fracture separators 6 includes two fracture separators 6 spaced one borehole distance apart and equipped with a power source for movement, enabling segmented shale oil recovery and preventing waste caused by large-scale shale oil outflow. Preferably, the production aid 4 is fixedly sleeved onto the fracturing fluid inlet pipe 3 by a pipe retainer located inside the drive unit 5. Thus, 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 recovery efficiency. In this embodiment, the power source for the movement of the fracture separators 6 is the same as that for the drive unit 5 that drives the production aid 4 to move along the wellbore.

[0040] Among them, such as Figure 1 As shown, the fracturing fluid injection system also includes a connected fracturing fluid mixing tank 7 and a fracturing fluid booster 8. The fracturing fluid booster 8 is connected to the input end of the fracturing fluid input pipe 3. The oil production unit 2 is equipped with an oil delivery pipe, the input end of which is located at the oil production end, and the output end of which is connected to an oil separator 9. Preferably, the fracturing fluid mixing tank 7 is equipped with a fracturing fluid storage chamber and a proppant storage chamber.

[0041] Preferably, the shale oil fracturing and recovery device also includes a surface control system, which is used to control the oil pump 2, drive unit 5, and fracture separator 6 from the ground to achieve efficient recovery of shale oil throughout the well.

[0042] Preferably, the shale oil fracturing and recovery device includes multiple sets of six fracture separators, which are spaced apart along the inner side of the wellbore. The interval between two adjacent sets of six fracture separators is at most one borehole distance. This ensures that if one fracture separator fails, an adjacent fracture separator can quickly move and replace the failed one, guaranteeing the effectiveness of the wellbore isolation sections during shale oil staged recovery and preventing large-scale shale oil outflow, thus achieving stable shale oil recovery. In one preferred embodiment, the distance between boreholes is 20m to 30m.

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

[0044] According to one embodiment of the present invention, such as Figure 3 and Figure 5 As shown, the production aid 4 includes a power module 41, an intermediate transmission assembly 42, and a spiral production aid 43. Along the extension direction of the fracturing fluid input pipe 3, the intermediate transmission assembly 42 and the spiral production aid 43 are interleaved to form a flexible production aid body, allowing it to adapt to complex wellbore trajectories and facilitating the movement of bottomhole oil towards the wellhead within the vertical climbing and bending sections of the drilling. Furthermore, both ends of the production aid body are connected to the intermediate transmission assembly 42, and both ends are symmetrically connected to drive units 5 via the power module 41, thus enhancing the stability and reliability of the production aid 4. By controlling the rotation direction of the two power modules 41, the delivery direction of the production aid body can be controlled, enabling it to deliver fracturing fluid to the inside of the well during fracturing fluid injection, reducing injection fracturing time. Simultaneously, it acts as a stirrer, ensuring rapid and thorough mixing of the fracturing fluid and shale oil, preventing shale oil blockage and improving shale oil fluidity. It can also deliver the mixture of fracturing fluid and shale oil to the outside of the well during oil production, improving recovery efficiency. The intermediate transmission assembly 42, the spiral extraction aid 43, and the drive unit 5 are all equipped with channels for the fracturing fluid input pipe 3 to pass through.

[0045] In a preferred embodiment, when the production aid 4 moves along the borehole, the surface control system activates the drive units 5 at both ends of the production aid 4. By controlling the output direction of the two drive units 5 respectively, the drive unit 5 at the front end of the movement direction applies a pulling force to the production aid 4, and the drive unit 5 at the rear end of the movement direction applies a pushing force to the production aid 4, so that the production aid 4 moves quickly to the target position. Of course, it is also possible to activate only one drive unit 5 to move the production aid 4, with the other as a backup; this application does not impose any restrictions on this.

[0046] According to one embodiment of the present invention, such as Figure 4As shown, the drive unit 5 includes a telescopic sleeve 51, a sliding sleeve 52, an elastic element 53, and multiple drive components 54. The telescopic sleeve 51 has a cylinder 511 and a piston cylinder 512 slidably connected. The free end of the piston cylinder 512 extends radially outward to form an anti-detachment baffle. A power module 41 is connected to the cylinder 511. The sliding sleeve 52 is slidably sleeved outside the cylinder 511. The elastic element 53 is sleeved outside the piston cylinder 512, and both ends of the elastic element 53 abut against the sliding sleeve 52 and the anti-detachment baffle, respectively. The multiple drive components 54 extend along the sliding sleeve 52. The drive assembly 54, evenly distributed circumferentially, includes a drive motor 541, a first connecting rod group 542, a second connecting rod group 543, and traveling wheels 544. One end of the second connecting rod group 543 is hinged to the cylinder 511, and the other end is hinged to the middle of the first connecting rod group 542. One end of the first connecting rod group 542 is hinged to the sliding sleeve 52, and the other end of the first connecting rod group 542 is rotatably connected to the traveling wheel 544. The drive motor 541 is fixedly connected to the first connecting rod, and the output shaft of the drive motor 541 is driven by the traveling wheel 544. Thus, the drive unit 5, located inside the well, contacts the well wall through multiple traveling wheels 544, ensuring that the telescopic sleeve 51 remains on the centerline of the well, thereby limiting the position of the production aid 4 relative to the well and preventing collisions between the production aid 4 and the well wall. This ensures the efficiency and service life of the production aid 4. By extending and retracting the telescopic sleeve 51, the distance between the traveling wheel 544 and the drilling centerline can be changed, allowing the drive unit 5 to move within wells of different diameters, thus enabling the production aid 4 to adapt to production operations in wells of varying diameters. Driven by the drive motors 541, multiple traveling wheels 544 move along the well wall, driving the production aid 4 and fracturing fluid inlet pipe 3 to move along the inner side of the well, facilitating shale oil recovery throughout the well. In a preferred embodiment, the drive unit 5 includes three drive components 54 arranged at 120° intervals along the circumference of the sliding sleeve 52, ensuring that the drive unit 5 is always stably supported on the drilling centerline by the three traveling wheels 544, thereby guaranteeing better drive stability. Preferably, the elastic element 53 is a spring.

[0047] According to one embodiment of the present invention, such as Figure 5 As shown, the power module 41 includes a transmission component 411 and a power assembly 412. The power assembly 412 is fixedly connected to the free end of the cylinder 511, and the transmission component 411 is drivingly connected between the power assembly 412 and the mining assistance body. For example, the transmission component 411 is a transmission pulley, which meshes with the power assembly 412 and is rotatably connected to the intermediate transmission component 42 at the end of the mining assistance body to achieve power transmission for the rotation of the mining assistance body.

[0048] According to one embodiment of the present invention, such as Figure 6As shown, the intermediate transmission assembly 42 includes a protective body and multiple transmission rod assemblies. The protective body has an outer telescopic connecting pipe 421 and protective outer pipes 422 symmetrically connected to both ends of the outer telescopic connecting pipe 421. One end of the protective outer pipe 422 connected to the outer telescopic connecting pipe 421 is connected to a first end plate 423, and the other end of the protective outer pipe 422 is connected to a second end plate 424. Multiple transmission rod assemblies are evenly distributed in the protective outer pipe 422 along the circumferential direction of the protective body. Each transmission rod assembly 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 424. On the 3rd, an elastic connector 427 is sleeved at one end of the transmission connecting rod 426 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 inside the two protective outer tubes 422 are correspondingly connected through the transmission connecting rod 426. The intermediate transmission assembly 42 located in the middle of the mining auxiliary body is fixedly embedded between the two spiral mining auxiliary components 43 through the protective outer tube 422. The intermediate transmission assemblies 42 located at both ends of the mining auxiliary body are rotatably connected to the transmission component 411 through one of the protective outer tubes 422, and fixedly embedded to the spiral mining auxiliary component 43 through the other protective outer tube 422. In this way, the intermediate transmission assembly 42 forms a universal coupling system. The change in the diameter of the protective outer tube 422 is offset by the sliding of the transmission connecting rod 426 relative to the positioning sleeve 425. The elastic connector 427 is provided so that the two interconnected transmission connecting rods 426 extend by the same distance through the elastic force, thereby ensuring the realization of the universal coupling system. At the same time, the elastic connector 427 is used to assist the transmission connecting rod 426 in resetting. Preferably, the elastic connector 427 is a spring.

[0049] According to one embodiment of the present invention, such as 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 pipe connects the two protective inner tubes 428 within the two protective outer tubes 422. The other end of the protective inner tube 428 is sealed to the second end plate 424. The first end plate 423 has a through hole for the protective inner tube 428 to pass through. The connection between the protective inner tube 428 and the inner telescopic connecting pipe forms an internal channel for the fracturing fluid input pipe 3 to pass through, thus isolating the fracturing fluid input pipe 3 from the transmission rod assembly and preventing mutual interference. Furthermore, the other end of the protective inner tube 428 is sealed to the second end plate 424 via a liquid-proof assembly 429 to prevent fracturing fluid and shale oil from entering 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, such as Figure 7As shown, the slot separator 6 includes the aforementioned drive unit 5, and a support member 61 is fixedly connected to the anti-detachment baffle. A sealing airbag 62 is fitted over the support member 61. Exemplarily, an air supply system consisting of a miniature high-pressure gas tank, an electric air pump, airbag tubing, a two-way solenoid valve, a pressure sensor, and a lithium battery pack is integrated within the internal space of the telescopic sleeve 51 and the support member 61 to provide a sealing gas source for the sealing airbag 62. When the slot 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 inlet valve of the two-way solenoid valve. Compressed gas from the miniature high-pressure gas tank is delivered to the sealing airbag 62 through the airbag tubing, causing the sealing airbag 62 to inflate and adhere to the well wall, forming a partial seal. During this process, the pressure sensor monitors the pressure inside the sealing airbag 62 in real time. Once a preset threshold is reached, the electric air pump and inlet valve are shut off, and the sealing airbag 62 remains in a sealed state. When the gap separator 6 needs to be moved, the sealing airbag 62 enters the venting stage. The ground control system sends a venting command, opening the vent valve of the two-way solenoid valve. The gas inside the sealing airbag 62 is recovered to the miniature high-pressure gas tank through the vent valve. After venting for a preset time, the sealing airbag 62 resets, and each drive motor 541 starts, pushing the gap separator 6 along the wellbore via the travel wheels 544. The airbag piping, solenoid valve, and lithium battery pack are all designed with sealed protection structures to prevent liquid intrusion from affecting performance. In 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℃; the miniature high-pressure gas tank and airbag pipeline are made of 316L stainless steel to suit the downhole environment, and the sealing gas source stored in the miniature high-pressure gas tank is an inert gas; the electric air pump is a high-temperature resistant and explosion-proof miniature electric air pump; the lithium battery pack uses a high-capacity, 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 high-temperature environments; the ground control system transmits commands through an anti-interference wireless module and monitors the airbag status and lithium battery pack power in real time.

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

[0052] For example, a method applied to the above-mentioned shale oil fracturing and recovery device includes:

[0053] Step S0: Through detailed geological exploration and modeling, understand the distribution, thickness, porosity and other characteristics of shale layers, use this data to formulate a precise mining plan, ensure the optimization of drilling location and direction, and make boreholes and drill 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 surface control system controls at least one set of fracture separators 6 to move to the target position, the surface control system sends an inflation command. The air supply system receives the inflation command and starts the inflation procedure. The sealing airbags 62 of each fracture separator 6 inflate and seal the current well section. Moving at least one set of fracture separators 6 to the target position includes: placing one fracture separator 6 near the fracturing hole at the maximum oil production area, and placing the other fracture separator 6 further inside the well, maintaining a distance of one horizontal borehole between the two fracture separators 6.

[0055] Step S2: Place the production aid 4, which is connected to the drive unit 5 and the fracturing fluid input pipe 3, inside the well.

[0056] Step S3: Start the fracturing fluid injection system. Using the fracturing fluid booster 8, first inject the fracturing fluid stored in the fracturing fluid storage chamber of the fracturing fluid mixing tank 7 into the bottom of the well through the fracturing fluid input pipe 3. The fracturing fluid creates a high-pressure environment at the bottom of the well, which opens up the formation and generates fractures. Then, inject the proppant stored in the proppant storage chamber of the fracturing fluid mixing tank 7 into the fractures through the fracturing fluid input pipe 3 to maintain the stability of the fractures.

[0057] Step S4: The ground control system controls the power unit 412 to start and controls its rotation direction to accelerate the mixing of shale oil and fracturing fluid, and pushes the mixture of shale oil and fracturing fluid towards the outside of the well, thereby accelerating the recovery of shale oil; at the same time, the shale oil is drawn 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 for shale oil fracturing and recovery equipment provided by the present invention utilizes the aforementioned shale oil fracturing and recovery equipment to recover shale oil, enabling stable and efficient recovery of shale oil within the well.

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

[0060] According to one embodiment of the present invention, when the shale oil production in the current sealed section is declining, after at least one set of fracture separators 6 is unsealed, at least one set of fracture separators 6 and the production aid 4 are moved to the inside of the well by the distance of one borehole, and the production aid operation, hydraulic fracturing operation and shale oil recovery operation are repeated, and so on, until the oil production work of the entire well is completed.

[0061] For example, if the shale oil production in the current isolation section shows a downward trend, it indicates that the shale oil in the current isolation section has been basically harvested. At this time, the surface control system sends a venting command, the gas supply system receives the venting command and starts the venting procedure, the sealing gasbag 62 vents and contracts to release the seal, and sends a signal to the surface control system indicating that the seal is complete. Subsequently, the surface control system controls the drive unit 5 of the production aid 4 and the slot separator 6 to start, driving at least one set of slot separators 6 and the production aid 4 to continue moving inwards to the inside of the wellbore a distance of one borehole. The above-mentioned gas filling and sealing process is repeated. After the new well section is sealed, the above-mentioned production aid operation, hydraulic fracturing operation, and shale oil harvesting operation are repeated, and so on, until the entire well section production operation is completed. In a preferred embodiment, the surface control system controls the power unit 412 to stop rotating before controlling the production aid 4 to continue moving inwards to the inside of the well, so as to facilitate the smooth and rapid movement of the production aid 4 inwards.

[0062] The above descriptions are merely a few embodiments of the present invention. Those skilled in the art can make various modifications or variations to the embodiments of the present invention based on the content disclosed in the application documents without departing from the spirit and scope of the present invention.

Claims

1. A shale oil fracturing and 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 fracture separators, wherein the oil production end of the oil production machine is installed inside the well via the oil production device; The fracturing fluid injection system includes a fracturing fluid inlet pipe. An auxiliary production device is fixedly sleeved on the outside of the section of the fracturing fluid inlet pipe that extends into the wellbore. When the shale oil fracturing and recovery device is in fracturing operation, the auxiliary production device 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 auxiliary production device is used to push the mixture of fracturing fluid and shale oil towards the outside of the wellbore. A drive unit is connected to the auxiliary production device to drive its movement along the wellbore. At least one set of the slot separator group is used to be installed in the inner well section of the production aid to isolate and segment the well. The slot separator group includes two slot separators spaced apart by one borehole distance and having a moving power source. The fracturing fluid extraction device includes a power module, an intermediate transmission assembly, and a spiral extraction component. Along the extension direction of the fracturing fluid input pipe, the intermediate transmission assembly and the spiral extraction component are alternately connected to form a flexible extraction body. Both ends of the extraction body are the intermediate transmission assembly. The two ends of the extraction body are symmetrically connected to the drive unit through the power module. The intermediate transmission assembly, the spiral extraction component, and the drive unit are all provided with channels for the fracturing fluid input pipe to pass through. The drive unit includes: a telescopic sleeve, a cylinder and a piston cylinder slidably connected, the free end of the piston cylinder extending radially outward to form an anti-detachment baffle, and the power module connected to the cylinder; a sliding sleeve slidably sleeved outside the cylinder; an elastic element sleeved outside the piston cylinder, with both ends of the elastic element abutting against the sliding sleeve and the anti-detachment baffle respectively; and multiple drive components evenly distributed along the circumference of the sliding sleeve. Each drive component includes 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, and 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 drive motor is fixedly connected to the first connecting rod group, and the output shaft of the drive motor is drively connected to the traveling wheel. The power module includes a transmission component and a power unit. The power unit is fixedly connected to the free end of the cylinder, and the transmission component is drivingly connected between the power unit and the mining auxiliary body. The intermediate transmission assembly includes: a protective body having an outer telescopic connecting pipe and protective outer pipes symmetrically connected to both ends of the outer telescopic connecting pipe, one end of the protective outer pipe connected to the outer telescopic connecting pipe being connected to a first end plate, and the other end of the protective outer pipe being connected to a second end plate; multiple transmission rod groups evenly distributed along the circumference of the protective body within the protective outer pipes, each transmission rod group including a positioning sleeve and a transmission connecting rod slidably passing through the positioning sleeve, the positioning sleeve being fitted onto the first end plate, one end of the transmission connecting rod near the second end plate being sleeved with an elastic connecting member, the other end of the elastic connecting member being fixedly connected to the second end plate, and the multiple transmission rod groups within the two protective outer pipes being correspondingly connected via the transmission connecting rods; the intermediate transmission assembly located in the middle of the mining auxiliary body being fixedly embedded between the two spiral mining auxiliary components via the protective outer pipe; and the intermediate transmission assemblies located at both ends of the mining auxiliary body being rotatably connected to the transmission component via one of the protective outer pipes and fixedly embedded to the spiral mining auxiliary component via the other protective outer pipe.

2. The shale oil fracturing and recovery device according to claim 1, characterized in that, The intermediate transmission assembly also includes a protective inner tube coaxially embedded in the protective outer tube, and an inner telescopic connecting tube connecting the two protective inner tubes in the two protective outer tubes. The other end of the protective inner tube is sealed to the second end plate.

3. The shale oil fracturing and recovery device according to claim 1, characterized in that, The gap separator includes the drive unit, a support member is fixedly connected to the anti-detachment baffle, and a sealing airbag is fitted over the support member.

4. A method for use in the shale oil fracturing and recovery apparatus according to any one of claims 1-3, characterized in that, include: Place at least one set of slot separators inside the well and isolate and segment the well. After the isolation sections are completed, the production aid is placed inside the well. Turn on the power unit to enable the mining aid to begin mining operations; Hydraulic fracturing operations are performed at the bottom of the well via fracturing fluid input pipe; Shale oil is extracted using oil extraction machines.

5. The method of shale oil fracturing and recovery apparatus according to claim 4, characterized in that, Activating the power unit to enable the production aid to enter the production operation includes: when the shale oil fracturing and recovery device is in fracturing operation, rotating the power unit in a first direction to cause the spiral production aid to push the fracturing fluid along the inside of the well; when the shale oil fracturing and recovery device is in recovery operation, rotating the power unit in a second direction to cause the spiral production aid to push the shale oil along the outside of the well.

6. The method of shale oil fracturing and recovery apparatus according to claim 4, characterized in that, When shale oil production in the current isolation section is declining, after at least one set of the fracture separators is unsealed, at least one set of the fracture separators and the production aid are moved one borehole distance to the inside of the well, and the production aid operation, hydraulic fracturing operation and shale oil recovery operation are repeated, and so on, until the oil production of the entire well is completed.

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