High-pressure wellhead two-stage tandem connection self-energy-charging water pumping desander and working method

Abstract

The invention discloses a high-pressure well mouth two-stage tandem connection self-energy-charging water pumping desander and a working method. A first-stage water pumping pipe is arranged in an inner side cavity of a first-stage separator, a second-stage water pumping pipe is arranged at the bottom of an inner side cavity of a second-stage separator, an energy storage electric device is arranged in the second-stage separator, a self-energy-charging element is arranged in the second-stage separator, and the self-energy-charging element is arranged in the second-stage separator. A water suction pump body is arranged at the end part of the first-stage water suction pipe or the second-stage water suction pipe; the energy storage electric device comprises a motor and an energy storage device, and an energy converter is arranged in the self-charging element; and a cleaning triggering mechanism is arranged in the first-stage water pumping pipe. By arranging the internal water pumping mechanism, internal accumulated water is automatically discharged, the adopted drainage pipe does not need to be communicated with the outside of the sand remover, continuous work of the sand remover is guaranteed, energy is generated by means of gas power of natural gas, water is pumped, and the accumulated water is pumped and discharged.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas field development, and in particular relates to a high-pressure wellhead two-stage series-connected self-charging water pumping desander and a working method thereof. Background Art

[0002] During natural gas extraction, the raw gas directly extracted from the gas well often contains a small amount of sand particles. In particular, in recent years, in order to increase production, a large number of fracturing operations have been used. Some of the proppant gravel carried in the fracturing fluid will also rise to the wellhead with the extracted natural gas. If the gravel is not removed, it will erode the pipeline and even block the pipeline, which will seriously affect the service life of the gas transmission system. Therefore, desanders are generally used in gas fields to remove sand.

[0003] The desanders in the prior art generally use the effect of gravity separation, that is, the sand particles are retained in the sand accumulation tube at the bottom, and the natural gas continues to flow in the upper part. Natural gas extraction has its own characteristics. First of all, natural gas, like crude oil, is often a storage system with bottom water or edge water. With the process of natural gas extraction, the elastic energy of the water body will drive water into the gas reservoir along the high permeability zone, and will be carried out of the wellhead together with the natural gas. Since the natural gas extracted from the well contains water droplets or water vapor, it is easy to condense and remain in the desander during the desandering process. Once too much accumulates in the desander, it will block the pipeline and make the removed sand particles adhere to the equipment, making it difficult to remove, causing trouble for the normal operation of the desander, and even blocking the desander.

[0004] The patent publication number is CN209228350U, and the name is a patent application for a natural gas extraction desanding and dewatering device. It provides a three-stage separation method, in which copper sulfate desiccant is used to dry the gas. However, this method is difficult to process and install, and there are consumables that need to be replaced from time to time. The desander itself is a high-pressure mechanism. Once disassembled and installed, it will have a great impact on the sealing performance, and it will greatly consume manpower and cause the desanding work to be suspended. It is not easy to use in the actual natural gas purification process. Summary of the invention

[0005] In order to overcome the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a high-pressure wellhead two-stage series self-charging water pumping and desander and a working method. By adding a set of internal water removal devices inside, it can automatically generate energy inside without destroying the internal pressure and without the help of any external energy supply mechanism, and intelligently operate to adjust the pumping timing to achieve automatic discharge of internal accumulated water.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A high-pressure wellhead two-stage series self-charging pumping desander, comprising:

[0008] A primary separator, wherein the primary separator is connected to a primary sand accumulation cylinder via a gas-sand cut-off valve;

[0009] A secondary separator, wherein the secondary separator is connected to a secondary sand accumulation cylinder via a gas sand cut-off valve;

[0010] A connecting pipeline, both ends of which are connected to the primary separator and the secondary separator respectively;

[0011] Wherein, the inner cavity of the first-level separator is provided with a first-level water pumping pipe, the bottom of the inner cavity of the second-level separator is provided with a second-level water pumping pipe, and the first-level water pumping pipe is connected with the second-level water pumping pipe; the second-level separator is provided with an energy storage electric device, and the second-level separator is provided with a self-charging element, and the self-charging element is arranged at the outlet of the second-level separator; the end of the first-level water pumping pipe or the second-level water pumping pipe is provided with a water pump body; the energy storage electric device includes an electric motor and an energy storage device, and the electric motor is connected with the water pump body; the energy storage device Arranged in the cavity of the secondary separator, the energy storage device is connected to the self-charging element; an energy converter is arranged inside the self-charging element; a cleaning trigger mechanism is arranged in the primary water pumping pipe, and the cleaning trigger mechanism includes a retaining ring and a retaining cylinder assembly; a water pumping hole is arranged at the bottom of the primary water pumping pipe, the retaining ring is fixed on the water pumping hole, and the retaining cylinder assembly is movably sleeved on one end of the primary water pumping pipe close to the bottom of the primary separator; a touch segment is arranged at the end of the retaining ring close to the retaining cylinder assembly, and the touch segment is connected to the motor.

[0012] Optionally, neither the primary water pumping pipe nor the secondary water pumping pipe extends into the valve plate of the gas-sand cut-off valve.

[0013] Optionally, the retaining cylinder assembly includes an upper retaining cylinder, a lower buoy and a connecting rod, the upper retaining cylinder and the lower buoy are respectively arranged on the upper and lower sides of the retaining ring, and the upper retaining cylinder and the lower buoy are connected by the connecting rod.

[0014] Optionally, the first-stage separator is connected to an inlet pipeline, the second-stage separator is connected to an outlet pipeline, and the self-charging element is arranged between the contact surface of the second-stage separator and the outlet pipeline.

[0015] Optionally, the self-charging element is a hollow rotating body structure, a reduced diameter section is provided inside the self-charging element, and the energy converter is arranged at the end of the reduced diameter section.

[0016] Optionally, the energy converter is a spiral blade structure.

[0017] Optionally, a water suction channel connected from the water pump body to the outlet pipeline is provided in the wall of the self-charging element.

[0018] Optionally, the retaining ring includes a retaining ring body, and a plurality of fixing buckles are provided on both sides of the retaining ring body, and the fixing buckles are hollow arc-shaped notches with outer openings smaller than inner openings.

[0019] Optionally, a plurality of rows of small holes are provided on the side surface of the end of the secondary pumping pipe.

[0020] The working method of the high-pressure wellhead two-stage series self-charging pumping desander comprises the following steps:

[0021] S1: The natural gas with sand and water is flushed into the primary desander and enters the secondary desander through the connecting pipeline. The gas drives the energy converter to generate electricity and is stored in the energy storage device.

[0022] S2: When the water level in the first-stage desander contacts the retaining cylinder assembly, the entire cleaning trigger mechanism is driven to move upward, touching the touch section, and the pumping pump is started to form a vacuum area in the first-stage pumping pipe and the second-stage pumping pipe, and the gas and water are pumped away;

[0023] S3: After ensuring that the touch section does not contact the cleaning trigger mechanism, the water pump body stops, the cleaning trigger mechanism falls, and the cleaning trigger mechanism is limited by the retaining ring.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention realizes the automatic removal of the internal accumulated water by setting up an internal pumping mechanism, so that the accumulated water can flow into the subsequent dewatering and drying process. In addition, the drainage pipe used in the present invention does not need to be connected to the outside of the desander, avoiding possible influence on the internal pressure. The internal has its own production capacity and energy supply equipment. Through the design and improvement of the internal structure, without the need for additional modification of the desander structure, the newly added components can be installed, and the gas power of the natural gas itself can be relied on to generate energy and pump water, so that the accumulated water can be extracted and discharged, without the need for additional disassembly and replacement of the energy supply device or the installation of the energy supply mechanism through the wall of the desander, and the pipeline can be automatically cleaned and the pumping time can be adjusted according to the water level, so as to ensure the safety of construction and use on site and guarantee the service life of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings described herein are for explanation purposes only and are not intended to limit the scope of the present invention in any way. In addition, the shapes and proportional dimensions of the components in the drawings are only for illustration purposes to help understand the present invention, and are not intended to specifically limit the shapes and proportional dimensions of the components of the present invention. In the drawings:

[0027] Figure 1 It is a three-dimensional diagram of the external structure of the present invention;

[0028] Figure 2It is a schematic diagram of the cross-section internal structure of the present invention;

[0029] Figure 3 It is a rear longitudinal sectional view of the present invention;

[0030] Figure 4 for Figure 3 A magnified view of the middle detail;

[0031] Figure 5 for Figure 3 A local schematic diagram of area A;

[0032] Figure 6 for Figure 5 Schematic diagram of local section;

[0033] Figure 7 for Figure 3 A local schematic diagram of area B;

[0034] Figure 8 A cross-sectional view of the cleaning trigger mechanism;

[0035] Fig. 9 It is a bottom view of the retaining ring;

[0036] Among them, 1-first-level separator, 2-first-level sand accumulation cylinder, 3-second-level separator, 4-second-level sand accumulation cylinder, 5-gas sand cut-off valve, 6-inlet pipeline, 7-outlet pipeline, 8-connecting pipeline, 9-connecting column, 10-first-level water pumping pipe, 11-second-level water pumping pipe, 12-self-charging element, 13-energy storage electric device, 101-pipe section 1, 102-pipe section 2, 103-pipe section 3, 104-adapter, 105-adapter fixing ring, 106-cleaning Trigger mechanism, 121-self-charging element body, 122-charging flow channel, 123-water suction flow channel, 124-energy converter, 131-water pump body 1031-blocking ring, 1032-water pumping hole, 1061-upper blocking cylinder, 1062-lower buoy, 1063-connecting rod, 1061-upper blocking cylinder, 1062-lower buoy, 1063-connecting rod, 10311-blocking ring body, 10312-tactile segment, 10313-fixing buckle. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0038] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only embodiment.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0040] The present invention is described in detail below with reference to the accompanying drawings.

[0041] like Figure 1-9 As shown, a high-pressure wellhead two-stage series self-charging water pumping desander of the present invention includes a primary desander and a secondary desander, wherein the primary desander includes a primary separator 1 and a primary sand accumulation cylinder 2, and the secondary desander includes a secondary separator 3 and a secondary sand accumulation cylinder 4.

[0042] The primary separator 1 is connected to the primary sand accumulation cylinder 2 via a gas sand cut-off valve 5 , and the secondary separator 3 is connected to the secondary sand accumulation cylinder 4 via a gas sand cut-off valve 5 .

[0043] The primary separator 1 is connected to an inlet pipeline 6, and the secondary separator 3 is connected to an outlet pipeline 7. The primary separator 1 and the secondary separator 3 are connected via a connecting pipeline 8. The connecting pipeline 8 is parallel to the axis of the inlet pipeline 6 and the outlet pipeline 7 but not colinear.

[0044] like Figure 2 As shown, a primary water pumping pipe 10 is provided in the inner cavity of the primary separator 1, and a secondary water pumping pipe 11 is provided at the bottom of the inner cavity of the secondary separator 3. The primary water pumping pipe 10 is connected to the secondary water pumping pipe 11 and neither of them extends into the valve plate of the gas sand cut-off valve 5. The primary water pumping pipe 10 passes through the connecting pipeline 8 from the primary separator 1 and is connected to the secondary water pumping pipe 11.

[0045] The primary water pumping pipe 10 and the secondary water pumping pipe 11 converge to the self-charging element 12 and the energy storage electric device 13 arranged in the secondary separator 3, and the liquid in the primary desander and the secondary desander can be pumped out through the energy storage electric device 13.

[0046] like Figure 5As shown, the self-charging element 12 is disposed between the contact surfaces of the secondary separator 3 and the outlet pipeline 7 . Specifically, the self-charging element 12 is embedded in the outlet pipeline 7 .

[0047] The first-stage pumping pipe 10 and the second-stage pumping pipe 11 are both provided with a pump body 131 at one end close to the self-charging element 12. The energy storage motor 13 includes an energy storage device and an electric motor. The energy storage device is a battery for storing electrical energy. The electric motor is connected to the pump body 131 and is used to drive the pump body 131. The energy storage device is arranged in the upper part of the cavity of the second-stage separator 3 so as not to hinder the flow of natural gas. The electric motor is connected to the self-charging element 12, which is a hollow rotating body structure. A reduced diameter section is provided inside the self-charging element 12, and the reduced diameter section is the charging flow channel 122.

[0048] The end of the charging channel 122 is provided with an energy converter 124 with a spiral blade structure. The energy converter 124 can be rotated by the impact of natural gas and generate induced electrical energy, which is transmitted to the energy storage device for energy storage. The wall of the self-charging element 12 is provided with a water suction channel 123 connected from the water pump body 131 to the outlet pipeline 7. The water suction channel 123 can directly send the pumped water into the outlet pipeline 7 for discharge.

[0049] like Figure 4 As shown, the secondary water pumping pipe 11 is bent downward directly from the vicinity of the water pump body 131 and extends to the bottom of the secondary separator 3 . A plurality of rows of small holes are provided on the side of the end of the secondary water pumping pipe 11 .

[0050] The opening of the connecting pipeline 8 on one side close to the secondary separator 3 is provided with an adapter fixing ring 105. The primary water pumping pipe 10 includes a pipe section 1 101, a pipe section 2 102, and a pipe section 3 103. One end of the pipe section 101 is connected to the water pump body 131, and the other end is connected to the adapter fixing ring 105. An internal liquid channel connected to the primary water pumping pipe 10 is provided in the adapter fixing ring 105. The other end of the internal liquid channel is connected to the pipe section 2 102. The pipe section 2 102 is connected to the pipe section 3 103 through a connector 104.

[0051] like Figure 6 , 7As shown, the pipe section three 103 is vertically arranged in the first-stage separator 1 and extends to the bottom of the first-stage separator 1, and multiple rows of water extraction holes 1032 are provided at the bottom of the first-stage water extraction pipe 10. A cleaning trigger mechanism 106 is provided in the pipe section three 103, and the cleaning trigger mechanism 106 includes a retaining ring 1031, an upper retaining cylinder 1061, a lower buoy 1062 and a connecting rod 1063. A threaded section is provided on the water extraction hole 1032 for fixing the retaining ring 1031. The retaining ring 1031 is inserted upward from the bottom of the pipe section three 103 and fixed in the threaded section on the water extraction hole 1032. The upper retaining cylinder 1061 and the lower buoy 1062 are connected by a connecting rod 1063, and the diameter of the connecting rod 1063 is smaller than the fixing buckle 10313 but larger than the opening of the fixing buckle 10313.

[0052] The retaining ring 1031 includes a retaining ring body 10311, and a plurality of fixing buckles 10313 are arranged on both sides of the retaining ring body 10311. The fixing buckles 10313 are hollow arc-shaped notches with a small opening and a large interior. A touch segment 10312 is arranged at the end of the threaded hole of the retaining ring 1031. The touch segment 10312 is connected with an electric wire inside and connected to the motor through the primary pumping pipe 10. The electric wire is arranged on the inner wall of the primary pumping pipe 10 or in the through hole on the wall of the primary pumping pipe 10. When the touch segment 10312 is contacted by the lower buoy 1062, the pressure-sensitive sensor on the touch segment 10312 is triggered, and then the motor is started to pump water in the primary desander. The touch segment 10312 is close to the inner side of the retaining ring body 10311, and is not easily accidentally touched by gravel particles. The tactile segment 10312 is made of alloy material, which can ensure the rigidity and deformation recovery of the tactile segment and has good corrosion resistance.

[0053] The upper retaining cylinder 1061 and the lower buoy 1062 are respectively arranged on the upper and lower sides of the retaining ring 1031. When installing the retaining ring 1031, the cleaning trigger mechanism 106 and the retaining ring 1031 are first connected together, and then inserted from the bottom of the primary water pumping pipe 10, and installed on the threaded section of the primary water pumping pipe 10 through the threaded fixing sleeve of the retaining ring 1031. If there is any damage, it is also convenient to disassemble and replace it separately when disassembling and repairing the whole set of sand removers. The connecting rod 1063 is squeezed and slightly deformed and respectively inserted into the fixing buckle 10313.

[0054] like Figure 7 As shown, the adapter fixing ring 105 is connected to two identical primary water pumping pipes 10. The primary water pumping pipe 10 includes a first primary water pumping pipe and a second primary water pumping pipe, wherein the length of the pipe section 3 103 of the first primary water pumping pipe is less than the length of the pipe section 3 103 of the second primary water pumping pipe. The bottom end of the second primary water pumping pipe is higher than the bottom end of the first primary water pumping pipe.

[0055] There is a certain height difference between the cleaning trigger mechanism 106 of the first-level pumping pipe and the second-level pumping pipe, which can ensure that the pumping time of the first-level pumping pipe and the second-level pumping pipe are inconsistent, so as to reduce the energy consumption of pumping when the water accumulation height is relatively low, and increase the pumping force when the water accumulation height is relatively high. The cleaning positions are different, which can ensure that when the sand height is too high, even if the first-level pumping pipe below is accidentally blocked, the second-level pumping pipe can still work normally.

[0056] The upper retaining cylinder 1061 and the lower buoy 1062 are both plastic parts with a density less than that of water, and a conical section is provided at the top of the upper retaining cylinder 1061, and a sponge layer is provided inside the lower buoy 1062, and the sponge layer can contact the outer wall of the pipe section 3 103. The upper retaining cylinder 1061 and the lower buoy 1062 can cooperate to enable the axial movement on the retaining ring 1031 and be relatively fixed, and can both provide buoyancy, and the conical top of the upper retaining cylinder 1061 can block the sand particles falling from above, so as to avoid the difficulty of upward movement due to the buoyancy of water caused by too much sand particles accumulated on the top of the upper retaining cylinder 1061.

[0057] The first-level pumping pipe 10 includes two side-by-side structures, which are respectively used as the first-level pumping pipe 10 one and the first-level pumping pipe 10 two. Since the first-level separator 1 is the main separator, more water is generated inside it, so two parallel first-level pumping pipes 10 are set here to better meet the pumping needs.

[0058] A water pumping method of a high-pressure wellhead two-stage series self-charging water pumping desander comprises the following steps:

[0059] S1: Natural gas rushes into the primary desander with sand and water, most of the sand falls down and falls into the primary sand accumulation tube 2, and some water is retained inside. At this time, natural gas enters the secondary desander 3 from the connecting pipeline 8 with the remaining water and sand, and some sand and water are also allowed to fall in the secondary desander 3. At this time, the gas drives the energy converter 124 to generate electricity and store it in the energy storage device. When it is fully charged, charging stops.

[0060] S2: When there is a lot of water in the first-stage desander, if it touches the lower buoy 1062, it drives the entire cleaning trigger mechanism 106 to move upward, touches the touch segment 10312, and starts the water pump body 131 to form a vacuum area in the first-stage water pumping pipe 10 and the second-stage water pumping pipe 11, and drives the gas to be pumped away and then pumps water, and sends the water away through the outlet pipeline 7.

[0061] S3: After the device completes the set time and ensures that the touch segment 10312 does not contact the cleaning trigger mechanism 106, the pump body 131 stops, the cleaning trigger mechanism 106 falls under the action of gravity, and the pumping hole 1032 is scrubbed by the sponge, and the cleaning trigger mechanism 106 is limited by the retaining ring 1031. Optionally, the set pumping time is 3 minutes.

[0062] Unless otherwise specified, the device elements involved in the above embodiments are all conventional device elements, and the structural settings, working modes or control modes involved are all conventional settings, working modes or control modes in the art unless otherwise specified.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in the field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. A high-pressure wellhead two-stage series self-charging pumping desander, characterized in that: include: A primary separator (1), wherein the primary separator (1) is connected to a primary sand accumulation cylinder (2) via a gas sand cut-off valve (5); A secondary separator (3), wherein the secondary separator (3) is connected to a secondary sand accumulation cylinder (4) via a gas sand cut-off valve (5); A connecting pipeline (8), the two ends of which are respectively connected to the primary separator (1) and the secondary separator (3); The first-stage separator (1) is provided with a first-stage water pumping pipe (10) in the inner cavity, and the second-stage separator (3) is provided with a second-stage water pumping pipe (11) at the bottom of the inner cavity, and the first-stage water pumping pipe (10) is communicated with the second-stage water pumping pipe (11); the second-stage separator (3) is provided with an energy storage electric device (13), and the second-stage separator (3) is provided with a self-charging element (12), and the self-charging element (12) is arranged at the outlet of the second-stage separator (3); a water pump body (131) is arranged at the end of the first-stage water pumping pipe (10) or the second-stage water pumping pipe (11); the energy storage electric device (13) comprises an electric motor and an energy storage device, and the electric motor is connected to the water pump body (131); the energy storage device is arranged at the second-stage separator (3) ), the energy storage device is connected to the self-charging element (12); an energy converter (124) is arranged inside the self-charging element (12); a cleaning trigger mechanism (106) is arranged inside the primary water pumping pipe (10), and the cleaning trigger mechanism (106) comprises a retaining ring (1031) and a retaining cylinder assembly; a water pumping hole (1032) is arranged at the bottom of the primary water pumping pipe (10), the retaining ring (1031) is fixed on the water pumping hole (1032), and the retaining cylinder assembly is movably sleeved on one end of the primary water pumping pipe (10) close to the bottom of the primary separator (1); a touch segment (10312) is arranged at the end of the retaining ring (1031) close to the retaining cylinder assembly, and the touch segment (10312) is connected to the motor.

2. A high-pressure wellhead two-stage series self-charging pumping desander according to claim 1, characterized in that: The primary water pumping pipe (10) and the secondary water pumping pipe (11) do not extend into the valve plate of the gas sand cut-off valve (5).

3. A high-pressure wellhead two-stage series self-charging pumping desander according to claim 1, characterized in that: The retaining cylinder assembly comprises an upper retaining cylinder (1061), a lower buoy (1062) and a connecting rod (1063); the upper retaining cylinder (1061) and the lower buoy (1062) are respectively arranged on the upper and lower sides of the retaining ring (1031); and the upper retaining cylinder (1061) and the lower buoy (1062) are connected via the connecting rod (1063).

4. A high-pressure wellhead two-stage series self-charging pumping desander according to claim 1, characterized in that: The first-stage separator (1) is connected to an inlet pipeline (6), the second-stage separator (3) is connected to an outlet pipeline (7), and the self-charging element (12) is arranged between the contact surfaces of the second-stage separator (3) and the outlet pipeline (7).

5. A high-pressure wellhead two-stage series self-charging pumping desander according to claim 1, characterized in that: The self-charging element (12) is a hollow rotating body structure, a reduced diameter section is provided inside the self-charging element (12), and the energy converter (124) is arranged at the end of the reduced diameter section.

6. A high-pressure wellhead two-stage series self-charging pumping desander according to claim 1, characterized in that: The energy converter (124) is a spiral blade structure.

7. A high-pressure wellhead two-stage series self-charging pumping desander according to claim 1, characterized in that: A water suction channel (123) connected from a water pump body (131) to an outlet pipeline (7) is provided in the wall of the self-charging element (12).

8. A high-pressure wellhead two-stage series self-charging pumping desander according to claim 1, characterized in that: The retaining ring (1031) comprises a retaining ring body (10311), and a plurality of fixing buckles (10313) are provided on both sides of the retaining ring body (10311). The fixing buckles (10313) are hollow arc-shaped notches with outer openings smaller than inner openings.

9. A high-pressure wellhead two-stage series self-charging pumping desander according to claim 1, characterized in that: The end side of the secondary water pumping pipe (11) is provided with multiple rows of small holes.

10. A method for operating a high-pressure wellhead two-stage series self-charging pumping desander according to any one of claims 1 to 9, characterized in that: The steps include: S1: The natural gas is flushed into the primary desander with sand and water, and enters the secondary desander (3) through the connecting pipeline (8), and the gas drives the energy converter (124) to generate electricity, which is stored in the energy storage device; S2: When the water level in the first-stage desander contacts the retaining cylinder assembly, the entire cleaning trigger mechanism (106) is driven to move upward, touching the touch section (10312), and the pumping pump body (131) is started to form a vacuum area in the first-stage pumping pipe (10) and the second-stage pumping pipe (11), and the gas and water are pumped away; S3: After ensuring that the touch-sensing section (10312) does not contact the cleaning trigger mechanism (106), the water pump body (131) stops, the cleaning trigger mechanism (106) falls, and the cleaning trigger mechanism (106) is limited by the retaining ring (1031).

Images