Oil extraction wellhead natural gas recovery device

Abstract

The oil extraction wellhead natural gas recovery device comprises a filter, a compressor and a storage tank, the filter comprises an arc barrel, the top end and the bottom end of the arc barrel are fixedly connected with an outlet pipe and an inlet pipe respectively, an inner plate is arranged in the arc barrel, and two gas holes are formed in the middle of the inner plate; by means of the arrangement, when natural gas is filtered through the filter screens, the air pressure is small, impurities are only located on the surfaces of the filter screens and do not permeate into the filter screens, the adhesive force of the impurities is low, and the impurities attached to the surfaces of the filter screens can be separated from the filter screens more easily; and when the natural gas is subjected to back flushing from the upper side to the lower side of the filter screen, the air pressure is relatively high, so that impurities blocked at the lower side of the filter screen can be better blown off, and the whole wellhead gas recovery device can be better and continuously operated.

Description

Technical Field

[0001] The invention relates to a natural gas recovery device, in particular to an oil wellhead natural gas recovery device applied in the field of natural gas recovery. Background Art

[0002] A Chinese patent with publication number CN117052369B discloses a skid-mounted wellhead gas recovery device, which uses a filter and a compressor to recover natural gas from an oil wellhead. When the filter is in use, the airflow of the natural gas drives the centrifugal cylinder to rotate to separate impurities in the natural gas, and cooperates with the filter to intercept impurities in the natural gas. When the filter is used to intercept impurities in the natural gas, the filter is driven to vibrate by striking a vibration sleeve. The vibrating filter is conducive to ejecting fine particles intercepted on the filter from the mesh of the filter, thereby playing an automatic cleaning role.

[0003] Since the pressure of natural gas out of the wellhead is not fixed, the cleaning effect of the centrifugal drum is limited, and the filter plays the main filtering role. However, the cleaning effect is limited if the filter is only cleaned by knocking, and the entire wellhead gas recovery device cannot be operated continuously for a long time. Summary of the invention

[0004] In view of the above-mentioned prior art, the technical problem to be solved by the present invention is that since the pressure of the natural gas outlet from the wellhead is not fixed, the cleaning effect of the centrifugal cylinder is limited, and the filter screen plays a major filtering role, but the filter screen is only cleaned by knocking, and the cleaning effect is limited, and the entire wellhead gas recovery device cannot be operated continuously for a long time.

[0005] In order to solve the above problems, the present invention provides a natural gas recovery device at the oil wellhead, including a filter, a compressor and a storage tank, the filter includes an arc cylinder, the top and bottom ends of the arc cylinder are respectively fixedly connected with an outlet pipe and an inlet pipe, an inner plate is arranged inside the arc cylinder, two air holes are opened in the middle of the inner plate, and filter screens are installed inside the two air holes, the top and bottom surfaces of the inner plate are fixedly connected with an electric adjustment rod, the top and bottom surfaces of the inner plate are also fixedly connected with an air blowing pipe and an air collecting pipe, and one end of the air blowing pipe and the air collecting pipe are sealed and slidable A collection and extension pipe is connected, one end of which is fixedly connected to a cover sleeve, one end of which is in contact with the inner plate, a backblowing pipe and an external release pipe are fixedly connected to the side wall of the arc tube, the backblowing pipe and the external release pipe are respectively located on the upper and lower sides of the inner plate, one end of the backblowing pipe and the air blowing pipe, one end of the external release pipe and the air collection pipe are all connected through a flexible connecting pipe, a recovery pipe is fixedly connected to the side wall of the outlet pipe, the outer walls of the backblowing pipe and the recovery pipe are respectively fixedly connected to an upper air valve and a lower air valve, one end of the recovery pipe is connected to the compressor, and the compressor is connected to a storage tank.

[0006] As a further improvement of the present application, one end of the external tube is fixedly connected to a mounting block, the middle of the mounting block is rotatably connected to a rotating shaft, one end of the mounting block is fixedly connected to a motor, and the output end of the motor is fixedly connected to one end of the rotating shaft.

[0007] As a further improvement of the present application, one end of the rotating shaft is fixedly connected to a vertical pipe, the top end of the vertical pipe is fixedly connected to an igniter, and a flexible intermediate pipe is fixedly connected between the vertical pipe and the external tube.

[0008] As a further improvement of the present application, a heat-conducting ring is fixedly connected to the outer wall of the backflush tube close to the arc tube.

[0009] As another improvement of the present application, the filter screen comprises a square frame, the inner wall of the square frame is fixedly connected to two pairs of plates, and a movable plate is slidably connected between the two pairs of plates.

[0010] As another improved supplement of the present application, a cylinder is fixedly connected to the side wall of the square frame near the movable plate, a piston is slidably connected to the inner wall of the cylinder, a push rod is fixedly connected to the side wall of the piston, and an output end of the push rod is fixedly connected to the movable plate.

[0011] As another improved supplement of the present application, a plurality of flexible steel wire ropes arranged in a line are fixedly connected between the side walls of the movable panel and the inner walls of the plurality of square frames.

[0012] As another improvement of the present application, the middle portion of the arc tube is set to be an inverted cone, the upper portion of the arc tube is set to be a positive cone, and the inner plate is located in the middle portion of the arc tube.

[0013] As another improvement of the present application, an electric telescopic rod is fixedly connected to the top of the arc tube, the telescopic end of the electric telescopic rod is fixedly connected to one end of the inner plate, and an elastic sealing membrane is fixedly connected between the outer wall of the inner plate and the arc tube.

[0014] In summary, when natural gas is filtered through the filter, the air pressure is relatively low, so the impurities are only located on the surface of the filter and do not penetrate into the inside of the filter. In this way, the adhesion of impurities is relatively low, making it easier for impurities attached to the surface of the filter to detach from the filter, making subsequent cleaning more efficient. When natural gas is back-blown from the upper side to the lower side of the filter, the air pressure is relatively high, so the impurities blocking the lower side of the filter can be better blown away, so that the entire wellhead gas recovery device can operate continuously better.

[0015] By setting up an inverted cone arc tube and an electric telescopic rod, the position of the inner plate can be automatically adjusted according to the pressure change of the natural gas at the wellhead, optimizing the gas pressure borne by the filter, thereby improving the gas circulation effect and preventing impurities from entering the filter;

[0016] During the back-flushing cleaning process of the filter, the gas can also be heated to keep the filter loose, further improving the cleaning effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a flow chart of recovery of wellhead natural gas in the first and second embodiments of the present application;

[0018] Figure 2 This is a front cross-sectional view of the arc tube in the first embodiment of the present application;

[0019] Figure 3 This is a state diagram when the inner plate is located in the middle of the inverted cone in the first embodiment of the present application;

[0020] Figure 4 This is a front cross-sectional view of the inner plate in the first embodiment of the present application;

[0021] Figure 5 This is a state diagram of the cover sleeve covering the filter screen in the first embodiment of the present application;

[0022] Figure 6 This is a front cross-sectional view of the frame in the second embodiment of the present application;

[0023] Figure 7 It is a top view of the cross section of the frame in the second embodiment of the present application;

[0024] Figure 8 This is a top view of the cross-section of the mounting block in the second embodiment of the present application.

[0025] Description of the numbers in the figure:

[0026] 1. Filter; 2. Compressor; 3. Storage tank; 4. Arc tube; 5. Outlet pipe; 6. Inlet pipe; 7. Inner plate; 701. Air hole; 8. Filter; 801. Frame; 802. Counter plate; 803. Movable plate; 804. Cylinder; 805. Piston; 806. Push rod; 807. Flexible steel wire rope; 9. Electric telescopic rod; 10. Electric adjustment rod; 11. Blowing pipe; 12. Air collecting pipe; 13. Air collecting and extending pipe; 14. Elastic sealing membrane; 15. Cover; 16. Back-blowing pipe; 1601. Upper air valve; 17. External pipe; 18. Flexible connecting pipe; 19. Recovery pipe; 1901. Lower air valve; 20. Mounting block; 21. Rotating shaft; 22. Motor; 23. Vertical pipe; 24. Ignitor; 25. Heat-conducting ring; 26. Flexible intermediate pipe. DETAILED DESCRIPTION

[0027] Two implementation modes of the present application are described in detail below with reference to the accompanying drawings.

[0028] The first implementation method:

[0029] Figure 1-5The invention shows a natural gas recovery device at an oil wellhead, which includes a filter 1, a compressor 2 and a storage tank 3. The filter 1 includes an arc tube 4, the top and bottom ends of which are fixedly connected to an outlet pipe 5 and an inlet pipe 6, respectively. An inner plate 7 is arranged inside the arc tube 4, and two air holes 701 are opened in the middle of the inner plate 7. A filter screen 8 is installed inside the two air holes 701. An electric adjustment rod 10 is fixedly connected to the top and bottom surfaces of the inner plate 7. An air blowing pipe 11 and an air collecting pipe 12 are also fixedly connected to the top and bottom surfaces of the inner plate 7. One end of the air blowing pipe 11 and the air collecting pipe 12 are sealed and slidably connected to a collecting and extending pipe 13. The collecting and extending pipe 13 is A cover sleeve 15 is fixedly connected to one end, and one end of the cover sleeve 15 is in contact with the inner plate 7. A backblowing pipe 16 and an external pipe 17 are fixedly connected to the side wall of the arc tube 4. The backblowing pipe 16 and the external pipe 17 are respectively located on the upper and lower sides of the inner plate 7. The backblowing pipe 16 and one end of the air blowing pipe 11, and the external pipe 17 and one end of the air collecting pipe 12 are all connected through a flexible connecting pipe 18. A recovery pipe 19 is fixedly connected to the side wall of the outlet pipe 5. The outer walls of the backblowing pipe 16 and the recovery pipe 19 are respectively fixedly connected with an upper air valve 1601 and a lower air valve 1901. One end of the recovery pipe 19 is connected to the compressor 2, and the compressor 2 is connected to the storage tank 3.

[0030] The natural gas from the wellhead enters the interior of the arc cylinder 4 through the inlet pipe 6 and is discharged from the outlet pipe 5. Since the space inside the arc cylinder 4 is large, the gas pressure decreases when the natural gas circulates inside the arc cylinder 4. At the same time, impurities in the natural gas are filtered through the filter 8. When the filtered natural gas is discharged through the outlet pipe 5, the gas pressure increases. The lower gas valve 1901 is opened to allow the filtered natural gas to be discharged into the interior of the compressor 2 for compression and storage in the storage tank 3.

[0031] When the filter 8 is clogged, the two electric adjustment rods 10 are started at the same time to drive the retractable extension tube 13 to move, so that the cover sleeve 15 covers one of the filter screens 8, and the lower air valve 1901 is closed, and the upper air valve 1601 is opened. The filtered natural gas is back-blown on the filter screen 8 through the back-blowing pipe 16 and the blowing pipe 11, and the impurities clogging the filter screen 8 are discharged to the outside through the air collecting pipe 12 and the external discharge pipe 17.

[0032] Since the gas pressure is relatively low when it is filtered through the filter 8, the impurities are only located on the surface of the filter 8 and do not penetrate into the inside of the filter 8. In this way, the adhesion of the impurities is relatively low, making it easier for the impurities attached to the surface of the filter 8 to separate from the filter 8, making subsequent cleaning more efficient. When the natural gas is back-blown from the upper side to the lower side through the filter 8, the gas pressure is relatively high, so the impurities blocking the lower side of the filter 8 can be better blown away, allowing the entire wellhead gas recovery device to operate continuously better.

[0033] The second implementation method:

[0034] Figure 2-8A natural gas recovery device at an oil wellhead is shown. Different from the first embodiment, one end of the external tube 17 is fixedly connected to a mounting block 20, the middle part of the mounting block 20 is rotatably connected to a rotating shaft 21, one end of the mounting block 20 is fixedly connected to a motor 22, the output end of the motor 22 is fixedly connected to one end of the rotating shaft 21, one end of the rotating shaft 21 is fixedly connected to a vertical pipe 23, the top of the vertical pipe 23 is fixedly connected to an igniter 24, a flexible intermediate pipe 26 is fixedly connected between the vertical pipe 23 and the external tube 17, and a heat-conducting ring 25 is fixedly connected to the outer wall of the back-blowing tube 16 near the arc tube 4.

[0035] The filter screen 8 includes a square frame 801, the inner wall of which is fixedly connected to two pairs of plates 802, a movable plate 803 is slidably connected between the two pairs of plates 802, a cylinder 804 is fixedly connected to the side wall of the square frame 801 near the movable plate 803, a piston 805 is slidably connected to the inner wall of the cylinder 804, a push rod 806 is fixedly connected to the side wall of the piston 805, an output end of the push rod 806 is fixedly connected to the movable plate 803, and a plurality of flexible steel ropes 807 arranged in a line are fixedly connected between the side wall of the movable plate 803 and the inner walls of multiple boxes 801.

[0036] When natural gas is discharged from the external pipe 17, it will be discharged into the interior of the vertical pipe 23. At this time, the igniter 24 is started to ignite the natural gas, and the motor 22 is started to drive the igniter 24 to rotate to the lower side of the heat-conducting ring 25 to heat it. At this time, the natural gas inside the backflush pipe 16 is heated, so that the temperature of the natural gas blown back onto the filter 8 increases, and then the temperature inside the cylinder 804 increases and the pressure increases, so that the movable plate 803 moves to the right, causing the multiple flexible steel wire ropes 807 to relax, so that the dust blocked on the flexible steel wire ropes 807 is more easily blown off, and when the flexible steel wire ropes 807 are cleaned, the motor 22 is started to rotate to move the compressor 2 away from the heat-conducting ring 25. At this time, the temperature of the natural gas blown back onto the filter 8 decreases, the temperature inside the cylinder 804 decreases and the pressure decreases, so that the cylinder 804 moves to the left, and the flexible steel wire ropes 807 resume the filtering state. Through the above arrangement, the filter 8 can be better cleaned.

[0037] The middle part of the arc tube 4 is set to an inverted cone, the upper part of the arc tube 4 is set to a positive cone, the inner plate 7 is located in the middle part of the arc tube 4, the top of the arc tube 4 is fixedly connected with an electric telescopic rod 9, the telescopic end of the electric telescopic rod 9 is fixedly connected to one end of the inner plate 7, and an elastic sealing membrane 14 is fixedly connected between the outer wall of the inner plate 7 and the arc tube 4.

[0038] Since the pressure of natural gas discharged from the oil well varies, excessive pressure will cause impurities to enter the interior of the filter 8. Through the above arrangement, the middle part of the arc tube 4 is set to an inverted cone, and the air pressure on the lower side of the inverted cone is greater than the air pressure on the upper side. Starting the electric telescopic rod 9 can drive the inner plate 7 to move up and down, changing the air pressure on the filter 8 to be within a reasonable range.

[0039] In view of current practical needs, the above-mentioned implementation mode adopted in this application is not limited to the scope of protection. Various changes made within the knowledge scope of technical personnel in this field without departing from the concept of this application still fall within the scope of protection of the present invention.

Claims

1. A natural gas recovery device at an oil wellhead, comprising a filter (1), a compressor (2) and a storage tank (3), characterized in that: The filter (1) comprises an arc tube (4), the top and bottom ends of the arc tube (4) are respectively fixedly connected with an outlet pipe (5) and an inlet pipe (6), an inner plate (7) is arranged inside the arc tube (4), two air holes (701) are provided in the middle of the inner plate (7), and filter screens (8) are installed inside the two air holes (701), the top and bottom surfaces of the inner plate (7) are fixedly connected with an electric adjustment rod (10), the top and bottom surfaces of the inner plate (7) are also fixedly connected with an air blowing pipe (11) and an air collecting pipe (12), one end of the air blowing pipe (11) and the air collecting pipe (12) are sealed and slidably connected with a collecting and extending pipe (13), one end of the collecting and extending pipe (13) is fixedly connected with a cover sleeve (15), and the cover sleeve (15) is fixedly connected with the cover sleeve (15). The arc tube (4) is provided with a back-blowing pipe (16) and an externally-released pipe (17) fixedly connected to one end of the outlet pipe (5) and the inner plate (7); the back-blowing pipe (16) and the externally-released pipe (17) are respectively located on the upper side and the lower side of the inner plate (7); the back-blowing pipe (16) and one end of the air blowing pipe (11), and the externally-released pipe (17) and one end of the air collecting pipe (12) are all connected through a flexible connecting pipe (18); the side wall of the outlet pipe (5) is fixedly connected with a recovery pipe (19); the outer walls of the back-blowing pipe (16) and the recovery pipe (19) are respectively fixedly connected with an upper air valve (1601) and a lower air valve (1901); one end of the recovery pipe (19) is connected to the compressor (2); and the compressor (2) is connected to the storage tank (3).

2. The oil wellhead natural gas recovery device according to claim 1, characterized in that: One end of the external tube (17) is fixedly connected to a mounting block (20), the middle of the mounting block (20) is rotatably connected to a rotating shaft (21), one end of the mounting block (20) is fixedly connected to a motor (22), and the output end of the motor (22) is fixedly connected to one end of the rotating shaft (21).

3. The oil wellhead natural gas recovery device according to claim 2, characterized in that: One end of the rotating shaft (21) is fixedly connected to a vertical tube (23), the top end of the vertical tube (23) is fixedly connected to an igniter (24), and a flexible intermediate tube (26) is fixedly connected between the vertical tube (23) and the external tube (17).

4. The oil wellhead natural gas recovery device according to claim 3, characterized in that: The backflush pipe (16) is fixedly connected to the outer wall of the arc tube (4) close to a heat-conducting ring (25).

5. The oil wellhead natural gas recovery device according to claim 1, characterized in that: The filter screen (8) comprises a square frame (801), the inner wall of the square frame (801) is fixedly connected to two pairs of plates (802), and a movable plate (803) is slidably connected between the two pairs of plates (802).

6. The oil wellhead natural gas recovery device according to claim 5, characterized in that: The side wall of the square frame (801) close to the movable plate (803) is fixedly connected to a cylinder (804), the inner wall of the cylinder (804) is slidably connected to a piston (805), the side wall of the piston (805) is fixedly connected to a push rod (806), and the output end of the push rod (806) is fixedly connected to the movable plate (803).

7. The oil wellhead natural gas recovery device according to claim 6, characterized in that: A plurality of flexible steel wire ropes (807) arranged in a line are fixedly connected between the side walls of the movable plate (803) and the inner walls of the plurality of square frames (801).

8. The oil wellhead natural gas recovery device according to claim 1, characterized in that: The middle portion of the arc tube (4) is configured as an inverted cone, the upper portion of the arc tube (4) is configured as a forward cone, and the inner plate (7) is located in the middle portion of the arc tube (4).

9. The oil wellhead natural gas recovery device according to claim 8, characterized in that: The top end of the arc tube (4) is fixedly connected to an electric telescopic rod (9), the telescopic end of the electric telescopic rod (9) is fixedly connected to one end of the inner plate (7), and an elastic sealing membrane (14) is fixedly connected between the outer wall of the inner plate (7) and the arc tube (4).

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