Gas lift process and device

Abstract

The invention belongs to the technical field of oil and gas well gas production engineering, and particularly relates to a gas lift process and a gas lift device. The gas lift technology comprises the following steps that S1, at least one gas lift device is connected to an oil pipe in series and is put into a position, flooded by water, in a well, and the lower end of the oil pipe is in a closed state; s2, a pipeline is tripped into the oil pipe, and the lower end of the pipeline at least reaches the position, flooded by water, in the well; and S3, gas is pumped into the pipeline or the annulus of the pipeline and the oil pipe.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas well gas production engineering technology, specifically, it relates to a gas lift process and a gas lift device. Background Technology

[0002] Oil and gas development is a systematic project encompassing geology, drilling, well completion, production enhancement, and extraction and transportation. With rapid economic development, energy demand is rising sharply, and oil and gas development has shifted from conventional resources to unconventional resources such as tight oil and gas, shale oil and gas, and coalbed methane. Horizontal well fracturing technology has become the mainstream technology. Unconventional oil and gas resources are buried deep and have low porosity, often requiring hydraulic fracturing to establish oil and gas channels in the formation. To improve oil and gas recovery, it is necessary to increase the hydraulic fracturing displacement, pumped fluid volume, and proppant quantity to crush the oil and gas reservoir formation as much as possible. As oil and gas well development enters the middle and late stages, formation energy gradually decreases, fluid accumulates in the well, and oil and gas production declines rapidly. The solution to the above technical problems is to inject high-pressure gases such as compressed natural gas and nitrogen into the well. The compressed gas is injected through the annulus or tubing and enters through the gas lift valve on the tubing string to reduce the liquid density. Under fluid circulation, the liquid in the oil and gas well is lifted to the surface, reducing the resistance of the accumulated liquid to the natural gas in the formation, thereby releasing production capacity. Summary of the Invention

[0003] To address the technical problems described above, this invention aims to propose a gas lift process that can improve the efficiency of drainage and gas production in oil and gas wells.

[0004] According to the present invention, an air lift process is provided, comprising the following steps:

[0005] S1. Connect at least one air lift device in series to the tubing and lower it into the water-flooded part of the well, wherein the lower end of the tubing is in a closed state;

[0006] S2. A pipe is lowered into the tubing, and the lower end of the pipe reaches at least the position in the well that is flooded by water.

[0007] S3. Pump gas into the annulus of the pipeline or the pipeline and the oil pipe.

[0008] According to the present invention, an air-lift device is also provided, comprising:

[0009] Eccentric cylindrical body;

[0010] An air lift valve is disposed on the outside of the eccentric cylinder; and

[0011] A filter mechanism is installed on the outside of the eccentric cylinder. The filter mechanism is connected to the air lift valve. Fluid outside the eccentric cylinder enters the interior of the eccentric cylinder through the filter mechanism and the air lift valve in sequence.

[0012] In one specific embodiment, the filtration mechanism includes a second eccentric cylinder arranged parallel to the outside of the eccentric cylinder body, the end of the second eccentric cylinder being connected to the air lift valve, a first screen tube being provided inside the second eccentric cylinder, and at least one liquid inlet hole being provided on the side of the second eccentric cylinder corresponding to the position of the first screen tube.

[0013] In one specific embodiment, a scraping ring is slidably disposed between the first screen tube and the second eccentric cylinder. The scraping ring is configured to reciprocate along the axial direction of the first screen tube in response to pressure fluctuations of the fluid, thereby removing impurities from the surface of the first screen tube.

[0014] In one specific embodiment, the second eccentric cylinder includes a first sand-proof working cylinder and a second sand-proof working cylinder arranged coaxially, and the first sand-proof working cylinder and the second sand-proof working cylinder are connected by a connecting hole, the diameter of which is smaller than the inner diameter of the first screen tube.

[0015] In one specific embodiment, a second screen tube is provided inside the second sand-proof working cylinder.

[0016] In one specific embodiment, a conversion connector is provided at the end of the second sand control working cylinder away from the connection hole. One end of the conversion connector extends into the second sand control working cylinder and is connected to the second screen tube, and the other end of the conversion connector is connected to the air lift valve.

[0017] In one specific embodiment, the air lift valve includes a first eccentric cylinder arranged parallel to the outside of the eccentric cylinder body, a bypass hole provided on the outer wall of the eccentric cylinder body corresponding to the first eccentric cylinder, and a piston movable inside the first eccentric cylinder capable of blocking the bypass hole, the piston being configured to allow fluid to flow only from the first eccentric cylinder to the eccentric cylinder body.

[0018] In one specific embodiment, an adjusting head is provided at the end of the first eccentric cylinder by means of a threaded connection, and a spring is provided between the adjusting head and the piston, so that the elastic force of the spring can be adjusted by the adjusting head.

[0019] In one specific embodiment, a connecting sleeve for connecting to the filter mechanism is provided at the end of the first eccentric cylinder away from the adjusting head, and a limit ring is provided between the connecting sleeve and the piston.

[0020] In one specific embodiment, the connecting sleeve is connected to the filtration mechanism via a transition ring and a liquid transfer tube.

[0021] Compared with the prior art, the advantages of this application are as follows.

[0022] The gas injected using the gas lift process provided by this invention does not affect formation pressure, ensuring safe and reliable construction. Because the pipe inserted into the tubing is smaller, the gas flows faster within the pipe or in the small annulus between the pipe and the tubing due to the capillary effect, thus creating a greater negative pressure and enabling more efficient removal of accumulated fluid from the well.

[0023] The gas lift device provided by the present invention includes an eccentric cylinder, a gas lift valve, and a filtering mechanism. During operation, the fluid outside the eccentric cylinder needs to be filtered by the filtering mechanism before entering the eccentric cylinder through the gas lift valve, thereby preventing the gas lift valve from being blocked and improving the efficiency of drainage and gas production in oil and gas wells.

[0024] The present invention provides a movable sand scraping ring between the first screen pipe and the first sand control working cylinder. When the fluid passes through the sand scraping ring, under the pressure fluctuation of the fluid, the sand scraping ring will form an irregular reciprocating motion along the axial direction of the first screen pipe, thereby scraping off the dirt on the surface of the first screen pipe, preventing the surface of the first screen pipe from being blocked by dirt, thereby improving the efficiency of drainage and gas production in oil and gas wells. Attached Figure Description

[0025] The invention will now be described with reference to the accompanying drawings.

[0026] Figure 1 A schematic diagram of one embodiment of the air-lift device according to the present invention is shown;

[0027] Figure 2 A schematic diagram of an embodiment of the gas lift device according to the present invention installed in a wellbore is shown;

[0028] Figure 3 Showing Figure 1 A magnified view of part A in the middle;

[0029] Figure 4 Showing Figure 1 A magnified view of part B in the middle section;

[0030] Figure 5 Showing Figure 1 A magnified view of part C in the middle;

[0031] Figure 6 A schematic diagram of the air lift device in the vertical section is shown;

[0032] Figure 7 A schematic diagram of the air lift device in the horizontal section is shown.

[0033] In the diagram: 1. Eccentric cylinder; 11. Bypass hole; 12. First cylinder; 13. Second cylinder; 14. Eccentric flow channel; 15. Machining hole;

[0034] 2. Air lift valve; 21. First eccentric cylinder; 22. Piston; 23. Adjusting head; 24. Spring; 25. Connecting sleeve; 26. Limit ring;

[0035] 3. Filtration mechanism; 31. Second eccentric cylinder; 311. Liquid inlet; 312. First sand-proof working cylinder; 313. Second sand-proof working cylinder; 314. Connecting hole; 32. First screen tube; 33. Sand scraper ring; 34. Second screen tube; 35. Adaptor; 36. Retaining ring; 37. Plug;

[0036] 4. Transition loop;

[0037] 5. Liquid transfer tube;

[0038] 6. Protective sleeve;

[0039] 7. Pipelines;

[0040] 8. Oil pipes;

[0041] 10. Shaft;

[0042] 100. Air lift device.

[0043] In this application, all drawings are schematic and are used only to illustrate the principles of the invention, and are not drawn to scale. Detailed Implementation

[0044] The invention will now be described with reference to the accompanying drawings.

[0045] It should be noted that the directional terms or qualifiers such as "up" and "down" used in this application are all specific to the referenced [reference]. Figure 1 In other words, they are not used to define the absolute position of the components involved, but can vary depending on the specific circumstances.

[0046] According to the present invention, an air lift process is provided, such as Figure 6 and Figure 7 As shown, at least one air lift device 100 is first connected in series to the tubing 8 and lowered into the vertical or horizontal section of the well that is flooded by water. At this time, the bottom end of the tubing 8 is blocked. Then, a pipe 7 (usually a small-sized continuous tubing) is lowered into the tubing 8. The pipe 7 is inserted into the bottom end of the tubing 8 and the bottom end of the pipe 7 is open.

[0047] When the formation energy is sufficient, under the action of formation energy (formation pressure, natural gas pressure, etc.), due to the pressure difference between the inside and outside of the tubing 8, the accumulated liquid in the large annulus between the tubing 8 and the wellbore 10 is squeezed into the small annulus between the tubing 8 and the pipeline 7 through the gas lift device 100. The formation compressed gas (natural gas, etc.) enters the small annulus together and moves towards the surface along the tubing 8. During the movement, the natural gas expands in volume, continuously carrying the accumulated liquid to the surface, thereby achieving the effect of drainage and gas production.

[0048] When the formation energy is insufficient, the fluid accumulated in the large annulus between the tubing 8 and the wellbore 10 can enter the small annulus between the tubing 8 and the pipe 7 through the gas lift device 100, but its energy is insufficient to transport it to the surface along the tubing 8. When there is no fluid in the tubing 8, the pressure of the fluid in the large annulus can push the piston 22 to overcome the spring force and move upward, thereby connecting the bypass hole 11 with the large annulus. The fluid in the large annulus can enter the tubing 8 through the bypass hole 11. As the fluid in the large annulus continuously enters the tubing 8, the pressure in the large annulus gradually decreases, eventually decreasing to a level insufficient to push the piston 22 to overcome the spring force, thus opening the bypass hole 11 on the pipe wall of the piston 22. At this point, nitrogen, natural gas, or other gases are injected into pipe 7 (or the small annulus between pipe 7 and oil pipe 8) via a ground-based gas lift vehicle to pressurize it. Due to the pressure difference between the inside and outside of pipe 7, the liquid accumulated in oil pipe 8 will move from the small annulus between pipe 7 and oil pipe 8 (or from pipe 7) to the ground. The compressed gas expands in volume during the movement, continuously carrying the liquid accumulated in oil pipe 8 to the ground, thereby achieving the effect of drainage and gas extraction. When the liquid in the large annulus is replenished again to the point that it can push piston 22 upward, the above steps are repeated.

[0049] According to the present invention, an air-lift device 100 is also provided. For example... Figure 1 As shown, the air lift device 100 includes an eccentric cylinder 1, an air lift valve 2, and a filter mechanism 3.

[0050] In this embodiment, the eccentric cylinder 1 is generally cylindrical in shape. An eccentric flow channel 14 is provided through the interior of the eccentric cylinder 1. The central axis of the eccentric flow channel 14 is offset from the central axis of the eccentric cylinder 1, and the central axis of the eccentric flow channel 14 is parallel to the central axis of the eccentric cylinder 1. An upper connector for threaded connection with an oil pipe is provided at the upper end of the eccentric cylinder 1.

[0051] Due to the eccentric structure of the eccentric cylinder 1, there is space on its side to accommodate the air lift valve 2 and the filter mechanism 3. Both the air lift valve 2 and the filter mechanism 3 are located on the outside of the eccentric cylinder 1, and their central axes are parallel to and coincide with the central axis of the eccentric cylinder 1. The filter mechanism 3 connects the external space of the eccentric cylinder 1 to the air lift valve 2, while the air lift valve 2 connects the filter mechanism 3 to the internal space of the eccentric cylinder 1. In this configuration, fluid from outside the eccentric cylinder 1 must pass through the filter mechanism 3 and the air lift valve 2 sequentially to enter the interior of the eccentric cylinder 1. The filter mechanism 3 filters the fluid, preventing sand and other contaminants carried in the fluid from clogging the air lift valve 2.

[0052] According to the present invention, the eccentric cylinder 1 includes a first cylinder 12 and a second cylinder 13 coaxially and fixedly connected, and the air lift valve 2 and the filter mechanism 3 are respectively disposed on the outside of the first cylinder 12 and the second cylinder 13.

[0053] In this embodiment, as Figure 1 As shown, the first cylinder 12 is positioned above the second cylinder 13, the air lift valve 2 is positioned outside the first cylinder 12, and the filter mechanism 3 is positioned outside the second cylinder 13. By dividing the eccentric cylinder 1 into two parts, the first cylinder 12 and the second cylinder 13, the assembly of the various components can be facilitated. The specific assembly process is detailed below.

[0054] In a specific embodiment, such as Figure 1 and Figure 4 As shown, the filtration mechanism 3 includes a second eccentric cylinder 31 arranged parallel to the outside of the second cylinder 13. The upper end of the second eccentric cylinder 31 is connected to the air lift valve 2. A first screen tube 32 is arranged inside the second eccentric cylinder 31. At least one liquid inlet hole 311 is arranged on the side of the second eccentric cylinder 31 corresponding to the position of the first screen tube 32. A plug 37 is sealed and fixed at the lower end of the second eccentric cylinder 31. In this configuration, the liquid inlet hole 311 connects the inner cavity of the second eccentric cylinder 31 with the external space of the eccentric cylinder 1. The first screen tube 32 is arranged in the inner cavity of the second eccentric cylinder 31. The upper end of the second eccentric cylinder 31 is connected to the air lift valve 2. Therefore, fluid outside the eccentric cylinder 1 can enter the inner cavity of the second eccentric cylinder 31 through the liquid inlet hole 311. After being filtered by the first screen tube 32, the fluid enters the eccentric flow channel 14 of the eccentric cylinder 1 through the air lift valve 2.

[0055] In a preferred embodiment, the outer diameter of the first screen tube 32 is smaller than the inner cavity size of the second eccentric cylinder 31, meaning that an annular space exists between the inner walls of the first screen tube 32 and the second eccentric cylinder 31. A scraping ring 33 is movably disposed on the outer wall of the first screen tube 32, meaning that the scraping ring 33 can reciprocate axially within the annular space between the first screen tube 32 and the second eccentric cylinder 31. When fluid passes through the filter mechanism 3, the scraping ring 33 can reciprocate axially along the first screen tube 32 in response to fluid pressure fluctuations, thereby removing impurities from the surface of the first screen tube 32, preventing the first screen tube 32 from becoming clogged, and extending its service life.

[0056] In one specific embodiment, the second eccentric cylinder 31 includes a first sand-proof working cylinder 312 and a second sand-proof working cylinder 313 coaxially arranged, connected by a connecting hole 314. The diameter of the connecting hole 314 is smaller than the inner diameter of the first screen tube 32. The first screen tube 32 is coaxially fixed inside the first sand-proof working cylinder 312, and the upper end of the first screen tube 32 axially abuts against the connecting hole 314. A retaining ring 36 is provided between the plug 37 and the first screen tube 32, and the lower end of the first screen tube 32 axially abuts against the retaining ring 36. A plurality of liquid inlet holes 311 are arranged axially on the side of the first sand-proof working cylinder 312. In this configuration, when the fluid enters the inner cavity of the first sand-proof working cylinder 312 through the inlet hole 311, the fluid can only be filtered from the side of the first screen tube 32 and then enter the interior of the first screen tube 32 through the connection hole 314 and the retaining ring 36 respectively, since the upper and lower ends of the first screen tube 32 are sealed and abutted. Then, the fluid enters the second sand-proof working cylinder 313 from the upper end of the first screen tube 32 through the connection hole 314.

[0057] In this embodiment, as Figure 1 and Figure 4 As shown, the second eccentric cylinder 31 and the second cylinder body 13 are integrally formed. During the manufacturing process, a hole is drilled axially downwards from the upper end of the second eccentric cylinder 31 to form the second sand-proof working cylinder 313. A hole is drilled axially upwards from the lower end of the second eccentric cylinder 31 to form the first sand-proof working cylinder 312. Then, an axial hole is drilled between the first sand-proof working cylinder 312 and the second sand-proof working cylinder 313 to form a connecting hole 314. The first screen tube 32, the sand scraping ring 33, the retaining ring 36, and the plug 37 are inserted sequentially from the lower end of the first sand-proof working cylinder 312. Finally, the plug 37 is fixed and sealed to the first sand-proof working cylinder 312 by a threaded connection. The retaining ring 36 is used to install the first screen tube 32. The first screen tube 32 is connected to the retaining ring 36 by threads. The lower side of the retaining ring 36 abuts against the plug 37. Here, the retaining ring 36 actually plays a transition role. If the first screen tube 32 and the plug 37 are connected by threads, it will be difficult to connect the plug 37 and the second eccentric cylinder 31 by threads during installation because the center of gravity is too far away.

[0058] In a preferred embodiment, a second screen tube 34 is provided inside the second sand control working cylinder 313. With this arrangement, after the fluid is filtered by the first screen tube 32 inside the first sand control working cylinder 312, it can be filtered again by the second screen tube 34 inside the second sand control working cylinder 313, thereby enhancing the filtration effect on the fluid.

[0059] Furthermore, a conversion joint 35 is provided at the upper end of the second sand-proof working cylinder 313. For example... Figure 1 and 4 As shown, the upper end of the adapter 35 is connected to the air lift valve 2, and the lower end of the adapter 35 extends into the interior of the second sand control working cylinder 313, and is fixedly connected to the second screen tube 34. The adapter 35 is fixedly connected to the second sand control working cylinder 313 by a threaded connection. When it is necessary to replace the second screen tube 34, simply loosen the thread between the adapter 35 and the second sand control working cylinder 313, and then remove the adapter 35 from the top of the second sand control working cylinder 313 to remove the second screen tube 34 from the second sand control working cylinder 313, thereby replacing the second screen tube 34.

[0060] According to the present invention, such as Figure 1 and Figure 3 As shown, the air lift valve 2 includes a first eccentric cylinder 21 arranged parallel to the outside of the eccentric cylinder body 1. A bypass hole 11 is provided on the outer wall of the corresponding first eccentric cylinder 21 of the eccentric cylinder body 1. A piston 22 capable of blocking the bypass hole 11 is movably arranged inside the first eccentric cylinder 21. The piston 22 is configured to allow fluid to flow from the first eccentric cylinder 21 to the eccentric cylinder body 1.

[0061] In one specific embodiment, the first eccentric cylinder 21 is disposed on the outer side of the first cylinder body 12. The first eccentric cylinder 21 and the first cylinder body 12 are integrally formed. A through hole is drilled axially inside the first eccentric cylinder 21 to form a space capable of accommodating the piston 22. Figure 3 As shown, holes are drilled from the right side to the left of the first eccentric cylinder 21, forming machining holes 15 and bypass holes 11 on the outer right side of the first eccentric cylinder 21 and the inner wall of the first cylinder 12 in sequence. Then the machining holes 15 are completely sealed, for example, by welding.

[0062] An adjusting head 23 is provided at the upper end of the first eccentric cylinder 21 via a threaded connection. An elastic element is provided between the adjusting head 23 and the piston 22. The elastic force of the elastic element can be adjusted by adjusting the position of the adjusting head 23 relative to the first eccentric cylinder 21 via the thread. Specifically, the elastic element is constructed as a spring 24, or a bellows filled with inert gas can be provided between the adjusting head 23 and the piston 22 to serve as the elastic element.

[0063] In this embodiment, as Figure 3 As shown, the upper end of the piston 22 inside the first eccentric cylinder 21 axially abuts against the lower end of the spring 24. Without external force, the piston 22 is positioned at the bypass hole 11, thus blocking the bypass hole 11. The lower part of the piston 22 is connected to the external space of the eccentric cylinder 1 through the filter mechanism 3. When the pressure in the external space of the eccentric cylinder 1 exceeds the elastic force of the spring 24 and pushes the piston 22 upward, the piston 22 no longer blocks the bypass hole 11. At this time, the bypass hole 11 is connected to the external space of the eccentric cylinder 1 through the filter mechanism 3, and the fluid in the external space of the eccentric cylinder 1 can enter the eccentric flow channel 14 of the eccentric cylinder 1 through the filter mechanism 3 and the bypass hole 11.

[0064] In one specific embodiment, a connecting sleeve 25 for connection with the filter mechanism 3 is provided at the end of the first eccentric cylinder 21 furthest from the adjusting head 23, and a limit ring 26 is provided between the connecting sleeve 25 and the piston 22. Figure 3 As shown, the limiting ring 26 is inserted into the lower end of the first eccentric cylinder 21 through a clearance fit, and a step is provided on the limiting ring to axially abut against the lower end face of the first eccentric cylinder 21. The clearance fit of the limiting ring 26 facilitates installation; a threaded connection is unnecessary, and direct insertion into the first eccentric cylinder 21 is the simplest installation method. The connecting sleeve 25 is fixedly installed at the lower end of the limiting ring 26 through a threaded connection. The upper and lower ends of the limiting ring 26 abut against the piston 22 and the connecting sleeve 25, respectively. By setting the limiting ring 26, the piston 22 can be limited, allowing the piston 22 to move to the position of the bypass hole 11 under the action of the spring 24 without external force, thus sealing the bypass hole 11.

[0065] According to the present invention, the connecting sleeve 25 is connected to the filter mechanism 3 via the transition ring 4 and the liquid transfer tube 5. The transition ring 4 and the liquid transfer tube 5 facilitate assembly of the present invention.

[0066] like Figure 1 and Figure 5 As shown, a protective cylinder 6 is fixedly installed on the outside of the second sand-proof working cylinder 313. In this embodiment, the central axis of the protective cylinder 6 coincides with the central axis of the first eccentric cylinder 21 and the second eccentric cylinder 31. There is an axial gap between the upper end of the protective cylinder 6 and the first eccentric cylinder 21, and an axial gap between the lower end of the protective cylinder 6 and the second eccentric cylinder 31. The protective cylinder 6 provides a mounting base for fixing the liquid transfer pipe 5.

[0067] The protective cylinder 6 and the second sand-proof working cylinder 313 are integrally formed, with a through-hole drilled along the axial direction of the protective cylinder 6 to form a cavity for accommodating the liquid transfer pipe 5. That is, the liquid transfer pipe 5 passes through the interior of the protective cylinder 6, with its upper end extending above the protective cylinder 6 and connected to the connecting sleeve 25 via a transition ring 4. Specifically, both the upper and lower ends of the transition ring 4 are connected to the connecting sleeve 25 and the liquid transfer pipe 5 respectively via threaded connections. The lower end of the liquid transfer pipe 5 extends below the protective cylinder 6 and is connected to the conversion joint 35 via a threaded connection.

[0068] Figure 2 The structure of the sand control gas lift device 100 after entering the wellbore 10 is shown. During the gas lift process, gas is pumped into the annulus between the sand control gas lift device 100 and the wellbore 10, causing the annulus liquid column to be depressurized and the liquid column pressure to be superimposed with the gas pressure, pushing the piston 22 to overcome the spring force and expose the bypass hole 11 for automatic pressure relief and drainage; the gas pushes the annulus liquid into the device and the tubing string, and the gas flows and expands in the pipe towards the surface, forming a negative pressure, which carries the accumulated liquid in the pipe out of the well.

[0069] When the multi-stage air lift devices 100 are connected in series, when the annular fluid pressure is higher than the position of the first-stage air lift device 100, all the lower multi-stage air lift devices 100 will open to participate in the hydraulic diversion. As the annular fluid level decreases, the multi-stage air lift devices 100 will automatically close one by one from top to bottom (until the annular fluid pressure can no longer push the piston 22 in the last-stage air lift device 100).

[0070] It is easy to understand that although this embodiment provides a specific embodiment of an air lift device 100, the scope of protection of the air lift process claimed by the present invention is not limited to the use of the air lift device 100 given in this embodiment. Those skilled in the art can use any air lift device in the prior art based on the present invention.

[0071] In the description of this invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0072] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0073] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0074] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An air-lift process, characterized in that, The steps include the following: S1. Connect at least one air lift device in series to the tubing and lower it into the water-flooded part of the well, wherein the lower end of the tubing is in a closed state; S2. A pipe is lowered into the tubing, and the lower end of the pipe reaches at least the position in the well that is flooded by water. S3. Pump gas into the annulus of the pipeline or the pipeline and the oil pipe.

2. An air-lift device, characterized in that, For implementing the air lift process according to claim 1, comprising: Eccentric cylindrical body (1); An air lift valve (2) disposed on the outside of the eccentric cylinder (1); and Pipe (7) passing through the eccentric cylinder (1).

3. The air-lift device according to claim 2, characterized in that, The air lift device also includes a filter mechanism (3) disposed on the outside of the eccentric cylinder (1). The filter mechanism (3) is connected to the air lift valve (2). Fluid outside the eccentric cylinder (1) enters the interior of the eccentric cylinder (1) through the filter mechanism (3) and the air lift valve (2) in sequence. The filtration mechanism (3) includes a second eccentric cylinder (31) arranged parallel to the outside of the eccentric cylinder body (1). The end of the second eccentric cylinder (31) is connected to the air lift valve (2). A first screen tube (32) is provided inside the second eccentric cylinder (31). At least one liquid inlet hole (311) is provided on the side of the second eccentric cylinder (31) at a position corresponding to the first screen tube (32).

4. The air-lift device according to claim 3, characterized in that, A scraping ring (33) is slidably disposed between the first screen tube (32) and the second eccentric cylinder (31). The scraping ring (33) is configured to reciprocate along the axial direction of the first screen tube (32) in response to pressure fluctuations of the fluid, thereby removing impurities from the surface of the first screen tube (32).

5. The air-lift device according to claim 4, characterized in that, The second eccentric cylinder (31) includes a first sand-proof working cylinder (312) and a second sand-proof working cylinder (313) arranged coaxially. The first sand-proof working cylinder (312) and the second sand-proof working cylinder (313) are connected by a connecting hole (314), and the diameter of the connecting hole (314) is smaller than the inner diameter of the first screen tube (32).

6. The air-lift device according to claim 5, characterized in that, A second screen tube (34) is installed inside the second sand-proof working cylinder (313).

7. The air-lift device according to claim 6, characterized in that, A conversion connector (35) is provided at the end of the second sand control working cylinder (313) away from the connection hole (314). One end of the conversion connector (35) extends into the second sand control working cylinder (313) and is connected to the second screen tube (34). The other end of the conversion connector (35) is connected to the air lift valve (2).

8. The air-lift device according to any one of claims 2 to 7, characterized in that, The air lift valve (2) includes a first eccentric cylinder (21) arranged parallel to the outside of the eccentric cylinder body (1). A bypass hole (11) is provided on the outer wall of the eccentric cylinder body (1) corresponding to the first eccentric cylinder (21). A piston (22) capable of blocking the bypass hole (11) is movably arranged inside the first eccentric cylinder (21). The piston (22) is configured to allow fluid to flow from the first eccentric cylinder (21) to the eccentric cylinder body (1).

9. The air-lift device according to claim 8, characterized in that, An adjusting head (23) is provided at the end of the first eccentric cylinder (21) by means of a threaded connection. A spring (24) is provided between the adjusting head (23) and the piston (22). The elastic force of the spring (24) can be adjusted by the adjusting head (23).

10. The air-lift device according to claim 9, characterized in that, A connecting sleeve (25) is provided at the end of the first eccentric cylinder (21) away from the adjusting head (23), and a limit ring (26) is provided between the connecting sleeve (25) and the piston (22).

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