Nonmetal cable sheathed velocity string matched with electric high-speed booster pump at well bottom and mining technology

Abstract

The application discloses a well bottom electric high-speed booster pump matched nonmetal cable-coated velocity string and mining technology, relates to the underground gas production technical field, and the string comprises a cable-coated pipe group, a gas compressor group, a siphon pipe group, an induction sensor, a control valve and a separator. The application can change the original various gas production technologies which solve the liquid damping of the accumulated water layer in the well into a new technology of directly collecting the natural gas through the downhole boosting and artificial siphon induction below the liquid surface, artificially intervenes the blocked natural gas which cannot naturally rise, makes the natural gas cross the accumulated water layer in the well and is released to the ground in a controllable manner for collection. The separator can realize the separation and communication between the accumulated water layer and the natural gas collecting layer in the well through the control of the external total control component, prevents the sinking of the accumulated water layer, and avoids the influence on the stability of the natural gas collecting layer. The separation of the underwater gas on the separator greatly reduces the interference of the accumulated water layer on the bottom shaft flow gas compressor in the initial gas production period.

Description

Technical Field

[0001] This invention relates to the field of downhole gas production technology, specifically to a bottom-hole electric high-speed booster pump with a non-metallic cable-laid speed tubing string and production process. Background Technology

[0002] During natural gas production, as formation pressure decreases, the gas-water interface rises, and natural gas reserves diminish, formation water gradually infiltrates the wellbore. This forms a water-accumulated layer within the wellbore, increasing bottomhole back pressure and hindering the natural ascent of natural gas. Therefore, drainage production technology is a key technique for maintaining stable natural gas production and improving recovery rates.

[0003] Currently, gas extraction techniques such as bubble drainage, gas lift, and pumping water are commonly used. However, these methods are not very effective for existing low-yield, old, and marginal wells with low gas reserves and low formation pressure. Increasing production costs would lead to persistently high costs, complicated construction processes resulting in a large workload, and uncontrollable production fluctuations. Furthermore, existing extraction techniques require addressing the presence of aquifers beforehand, and cannot artificially remove the obstruction to the natural ascent of natural gas, further increasing the difficulty of extraction.

[0004] Therefore, a combination of a bottom-hole electric high-speed booster pump, a non-metallic cable-laying speed string, and mining technology is needed to solve the above-mentioned technical problems. Summary of the Invention

[0005] To achieve the above objectives, the present invention provides the following technical solution: On the one hand, a bottom-hole electric high-speed booster pump is equipped with a non-metallic cable laying speed string, including: a cable laying pipe assembly, an air compressor assembly, a siphon assembly, an induction sensor, a control valve, and a separator;

[0006] The cable laying pipe assembly is connected to an external gas collection mechanism at one end and to the compressor unit at the other end. The end of the compressor unit away from the cable laying pipe assembly is connected to the siphon pipe assembly. The sensing sensor is installed at the end of the siphon pipe assembly away from the compressor unit.

[0007] The cable-laying pipe assembly, the air compressor assembly, the siphon assembly, and the sensing sensor constitute a gas production tubing string, which can move within the gas production well.

[0008] The siphon assembly is equipped with the control valve, which can control the connection and blockage of the overall gas passage in the gas production string. The outer wall of the siphon assembly is equipped with the separator, which can isolate and connect the water accumulation layer and the natural gas gathering layer in the gas production well.

[0009] Furthermore, as a preferred embodiment, the cable laying conduit assembly includes: an outer cable laying conduit, an inner cable laying conduit, and a cable laying connecting conduit.

[0010] The outer cable conduit contains the inner cable conduit, and the cable connecting pipe is provided between the outer wall of the inner cable conduit and the inner wall of the outer cable conduit. The inner wall of the cable connecting pipe is in contact with the outer wall of the inner cable conduit, and the outer wall of the cable connecting pipe is in contact with the inner wall of the outer cable conduit.

[0011] The end of the cable-laying connecting pipe away from the inner cable-laying pipe is connected to the external gas collection mechanism, and the end of the inner cable-laying pipe away from the cable-laying connecting pipe is connected to the air compressor unit.

[0012] Furthermore, as a preferred embodiment, an electrical channel for the cable laying tube is formed between the inner wall of the outer cable laying tube, the outer wall of the inner cable laying tube, and the end of the cable laying connecting tube away from the external gas collection mechanism; an air channel for the cable laying tube is formed inside the inner cable laying tube; and the air channel for the cable laying tube is connected to the cable laying connecting tube.

[0013] Furthermore, as a preferred embodiment, the compressor unit includes: an axial flow compressor, an outlet adapter, and an inlet adapter;

[0014] The axial compressor is connected at one end to the inner cable tube via the outlet adapter, and at the other end to the siphon tube assembly via the inlet adapter.

[0015] Furthermore, as a preferred embodiment, the axial compressor includes: a housing, a body, an end cover, a rotor shaft, an impeller assembly, a guide shroud, an inner support sleeve, a compressor air passage, and an air inlet;

[0016] The impeller assembly is connected to one end of the outer casing via the end cover, and the end of the impeller assembly away from the end cover is connected to the air inlet adapter.

[0017] The housing contains the machine body, which is connected to the impeller assembly via the rotor shaft and the inner support sleeve. The inner support sleeve is provided with the flow guide at one end away from the rotor shaft.

[0018] The outer casing has multiple compressor air passages circumferentially located on the outer side of the machine body. The end cover is a cavity with multiple air ports circumferentially located, and each of the multiple air ports is connected to a corresponding multiple compressor air passage.

[0019] Furthermore, preferably, the air inlet adapter includes: an air inlet chamber;

[0020] The air intake chamber is located inside the air intake adapter. The air intake chamber includes a cylindrical cavity and a conical cavity. The conical cavity is shaped to match the guide shroud. The end of the conical cavity away from the cylindrical cavity is connected to the end cap cavity, and the end of the cylindrical cavity away from the conical cavity is connected to the siphon tube assembly.

[0021] Furthermore, preferably, the air outlet adapter includes an air outlet chamber;

[0022] The air outlet chamber is located inside the air outlet adapter. The air outlet chamber has multiple openings around its circumference, and each of the multiple openings is connected to a corresponding air passage of the compressor. The end of the air outlet chamber away from the opening is connected to the inner cable tube.

[0023] Furthermore, as a preferred embodiment, the siphon assembly includes: a sleeve, a siphon tube, a storage tube, a strip-shaped inlet, an internal gas intake inlet, and an external gas intake inlet;

[0024] The siphon tube is provided inside the sleeve, one end of the siphon tube is connected to the cylindrical cavity, and the outer wall of the other end is provided with the storage tube located inside the sleeve.

[0025] The casing has multiple strip-shaped openings around its circumference, the siphon pipe has multiple internal gas intake ports evenly distributed on the pipe wall inside the storage pipe, and the storage pipe wall has multiple external gas intake ports evenly distributed.

[0026] Furthermore, on the other hand, a mining process based on a bottom-hole electric high-speed booster pump coupled with a non-metallic cable-laying speed string includes the following steps:

[0027] S1 gas production tubing was inserted into the well;

[0028] S11: Inject the assembled gas production tubing string into the gas production well. At this time, the control valve and the separator are both closed. When the front end of the gas production tubing string enters and exits the water layer in the well, the sensor sends a signal. By analysis, the thickness and depth of the water layer in the well can be determined.

[0029] S12: The gas production tubing string continues to descend, and is anchored when the siphon tube group descends to the natural gas gathering layer in the well.

[0030] S13: Activate the separator to separate the water accumulation layer from the natural gas gathering layer in the well;

[0031] S2 Gas Gathering Channel Opening: Depending on the gas gathering conditions, different methods are used to control the valve to open, thus opening the gas gathering channel.

[0032] S3 gas production process: The compressor unit is started to generate a pressure difference in the siphon tube group, and then the natural gas in the natural gas gathering layer in the well is sucked into the siphon tube group. Under the action of the compressor unit, it is pushed directly towards the wellhead through the water accumulation layer in the well. The natural gas is finally transported to the surface through the cable pipe group.

[0033] Compared with existing technologies, this invention provides a bottom-hole electric high-speed booster pump with a non-metallic cable-laying speed string and a mining process, which has the following beneficial effects:

[0034] Advantage 1: The present invention can change various gas production processes that originally solve the liquid damping of the water accumulation layer in the well through the siphon section and the pressurization and pushing section into a new process of directly inducing gas production under the liquid surface through downhole pressurization and artificial siphon. Artificial intervention is carried out on the natural gas that is blocked and unable to rise naturally, enabling it to smoothly cross the water accumulation layer in the well and be controllably released to the ground for collection.

[0035] Advantage 2: The separator of the present invention is a process gate valve, which can achieve the isolation and connection between the water accumulation layer in the well and the natural gas gathering layer through the control of the external total control component. The separator prevents the sinking of the water accumulation layer in the well and avoids affecting the stability of the natural gas gathering layer. The isolation function of the separator with water below and gas above greatly reduces the interference of the water accumulation layer on the bottom axial flow compressor at the initial stage of gas production.

[0036] Advantage 3: The present invention can select different ways to open the gas production channels according to the gas production requirements, including electric control method, reverse nitrogen injection method, etc. And in the present invention, the control valve can be selected from electromagnetic slide valves, mechanical pressure slide valves, etc., to match the corresponding gas production channel opening methods. Brief Description of the Drawings

[0037] Figure 1 Schematic diagram of the non-metallic cable laying speed string structure for the bottom hole electric high-speed booster pump;

[0038] Figure 2 Schematic diagram of the cable laying pipe group structure of the non-metallic cable laying speed string for the bottom hole electric high-speed booster pump;

[0039] Figure 3 For Figure 1 A - A cross-sectional view in

[0040] Figure 4 Schematic diagram of the compressor air duct structure of the non-metallic cable laying speed string for the bottom hole electric high-speed booster pump;

[0041] Figure 5 Schematic diagram of the end cover cavity structure of the non-metallic cable laying speed string for the bottom hole electric high-speed booster pump;

[0042] Figure 6 Schematic diagram of the gas outlet adapter structure of the non-metallic cable laying speed string for the bottom hole electric high-speed booster pump;

[0043] Figure 7 Schematic diagram of the gas inlet adapter structure of the non-metallic cable laying speed string for the bottom hole electric high-speed booster pump;

[0044] Figure 8 Schematic diagram of the siphon pipe group structure of the non-metallic cable laying speed string for the bottom hole electric high-speed booster pump;

[0045] Figure 9This is a flowchart of the mining process described in this application;

[0046] In the diagram: 1. Cable laying duct assembly; 11. External cable laying duct; 12. Internal cable laying duct; 13. Cable laying connecting pipe; 14. Cable laying duct air passage; 15. Cable laying duct electrical passage; 2. Compressor unit; 21. Axial flow compressor; 211. Outer casing; 212. Body; 213. End cover; 214. Rotor shaft; 215. Impeller assembly; 216. Draft shield; 217. Inner support sleeve; 218. Compressor air passage; 219. 1. Gas inlet; 22. Gas outlet adapter; 221. Opening; 23. Gas inlet adapter; 231. Cylindrical cavity; 232. Conical cavity; 3. Siphon tube assembly; 31. Casing; 32. Siphon tube; 33. Storage tube; 34. Strip-shaped inlet; 35. Internal gas inlet; 36. External gas inlet; 4. Induction sensor; 5. Gas well; 6. Control valve; 7. Divider; 8. Internal vertical inlet; 9. External vertical inlet. Detailed Implementation

[0047] Please see Figures 1-9 The present invention provides a non-metallic cable laying speed string for a bottom hole electric high-speed booster pump, including: cable laying pipe assembly 1, air compressor assembly 2, siphon assembly 3, induction sensor 4, control valve 6, and separator 7.

[0048] Among them, one end of the cable laying pipe group 1 is connected to the external gas collection mechanism, and the other end is connected to the compressor group 2. The end of the compressor group 2 away from the cable laying pipe group 1 is connected to the siphon pipe group 3. The end of the siphon pipe group 3 away from the compressor group 2 is equipped with a sensing sensor 4.

[0049] The gas production tubing string consists of cable pipe assembly 1, compressor assembly 2, siphon assembly 3, and sensor 4. The gas production tubing string can move within the gas production well 5.

[0050] A control valve 6 is installed inside the siphon tube assembly 3. The control valve 6 can control the connection and blockage of the overall gas passage in the gas production string. A separator 7 is installed on the outer wall of the siphon tube assembly 3. The separator 7 can isolate and connect the water accumulation layer and the natural gas gathering layer in the gas production well 5.

[0051] In this embodiment, please refer to Figure 1 As shown, the entire gas duct within the gas sampling string adopts a fully enclosed structure. Its front end includes a siphon tube assembly 3 and a sensing sensor 4, the middle end includes a compressor unit 2, and the rear end includes a cable-laying tube assembly 1. The gas sampling string includes a siphon section and a pressurization and lift section. The siphon section includes a compressor unit 2 and a siphon tube assembly 3, and the pressurization and lift section includes a compressor unit 2 and a cable-laying tube assembly 1.

[0052] As a preferred embodiment, the present invention can replace the original gas production processes that first solve the liquid damping of the water layer in the well with a new process that directly induces gas production below the liquid surface through downhole pressurization and artificial siphon by means of a siphon section and a pressurization and lifting section. This process artificially intervenes to allow natural gas that cannot rise naturally due to the obstruction of the water layer in the well to successfully cross the water layer in the well and be released to the surface for collection in a controlled manner.

[0053] Furthermore, the cable laying conduit assembly 1 includes: an outer cable laying conduit 11, an inner cable laying conduit 12, and a cable laying connecting conduit 13.

[0054] Among them, an inner cable pipe 12 is provided inside the outer cable pipe 11, and a cable connecting pipe 13 is provided between the outer wall of the inner cable pipe 12 and the inner wall of the outer cable pipe 11. The inner wall of the cable connecting pipe 13 is attached to the outer wall of the inner cable pipe 12, and the outer wall of the cable connecting pipe 13 is attached to the inner wall of the outer cable pipe 11.

[0055] The end of the cable-laying connecting pipe 13 away from the inner cable-laying pipe 12 is connected to the external gas collection mechanism, and the end of the inner cable-laying pipe 12 away from the cable-laying connecting pipe 13 is connected to the air compressor unit 2.

[0056] Furthermore, a cable laying pipe electrical channel 15 is formed between the inner wall of the outer cable laying pipe 11, the outer wall of the inner cable laying pipe 12, and the end of the cable laying connecting pipe 13 away from the external gas collection mechanism. A cable laying pipe air passage 14 is formed inside the inner cable laying pipe 12, and the cable laying pipe air passage 14 is connected to the cable laying connecting pipe 13.

[0057] In this embodiment, please refer to Figure 2 As shown, the cable-laying assembly 1 is a multi-channel structure composed of an outer cable-laying pipe 11, an inner cable-laying pipe 12, and a cable-laying connecting pipe 13. The cable-laying pipe air passage 14 within the inner cable-laying pipe 12 is a continuous pipe with a diameter less than 50mm, made of POK material. Under the same flow rate requirements, the internal flow velocity of the inner cable-laying pipe 12 increases, improving its fluid-carrying capacity. Furthermore, due to the material, the pipe damping of the inner cable-laying pipe 12 is much less than that of a steel pipe of equal diameter, effectively reducing well resistance.

[0058] Furthermore, the compressor unit 2 includes: an axial compressor 21, an outlet adapter 22, and an inlet adapter 23;

[0059] One end of the axial compressor 21 is connected to the inner cable tube 12 through the outlet adapter 22, and the other end is connected to the siphon tube group 3 through the inlet adapter 23.

[0060] In a preferred embodiment, the operation of the axial compressor 21 includes two processes: negative pressure intake and pressurization push. The negative pressure intake process uses negative pressure to draw natural gas from the natural gas gathering layer in the well into the axial compressor 21 through the siphon pipe group 3. The pressurization push process uses pressurization to push the natural gas in the axial compressor 21 into the cable laying pipe group 1, and finally successfully discharges the natural gas from the wellhead and collects it.

[0061] In this embodiment, please refer to Figure 3 As shown, the negative pressure intake process of the axial compressor 21 is formed in the siphon section, during which the pressure in the siphon section changes from P1 to P2 (P2 < P1). The boosting and thrusting process of the axial compressor 21 is formed in the boosting and thrusting section, during which the pressure in the boosting and thrusting section changes from P2 to P3 (P3 > P2). It should be noted that P1, P2, and P3 are only used as illustrations of pressure changes in the two processes of negative pressure intake and boosting and thrusting, and do not represent specific pressure values ​​at any particular location.

[0062] In this embodiment, specifically, please refer to Figure 1 , Figure 2 and Figure 3 As shown, after the natural gas is collected by the siphon section, it enters the pressurization and lifting section, where the axial compressor 21 pressurizes and lifts the natural gas. Specifically, the natural gas, after being pressurized by the axial compressor 21, is pushed to the outlet adapter 22, then enters the inner cable pipe 12 in the cable assembly 1, and continues to be discharged towards the wellhead, finally being collected by the external gas gathering mechanism.

[0063] Furthermore, the axial compressor 21 includes: a housing 211, a body 212, an end cover 213, a rotor shaft 214, an impeller assembly 215, a guide shroud 216, an inner support sleeve 217, a compressor air passage 218, and an air port 219.

[0064] Among them, one end of the outer casing 211 is connected to the impeller assembly 215 via the end cover 213, and the end of the impeller assembly 215 away from the end cover 213 is connected to the air inlet adapter 23.

[0065] An organic body 212 is installed inside the outer casing 211. The organic body 212 is connected to the impeller assembly 215 through the rotor shaft 214 and the inner support sleeve 217. A guide shroud 216 is provided at the end of the inner support sleeve 217 away from the rotor shaft 214.

[0066] The outer casing 211 has multiple compressor air passages 218 circumferentially located on the outer side of the body 212. The end cover 213 is a cavity with multiple air ports 219 circumferentially located. The multiple air ports 219 are respectively connected to the multiple compressor air passages 218 one by one.

[0067] Furthermore, the air intake adapter 23 includes: an air intake chamber;

[0068] The air intake chamber is located inside the air intake adapter 23. The air intake chamber includes a cylindrical cavity 231 and a conical cavity 232. The conical cavity 232 is shaped to match the guide shroud 216. The end of the conical cavity 232 away from the cylindrical cavity 231 is connected to the cavity of the end cap 213. The end of the cylindrical cavity 231 away from the conical cavity 232 is connected to the siphon tube assembly 3.

[0069] Furthermore, the air outlet adapter 22 includes: an air outlet chamber;

[0070] The air outlet chamber is located inside the air outlet adapter 22. Multiple openings 221 are provided around the circumference of the air outlet chamber. Each of the multiple openings 221 is connected to a corresponding air compressor passage 218. The end of the air outlet chamber away from the opening 221 is connected to the inner cable tube 12.

[0071] In this embodiment, please refer to Figure 4 , Figure 5 , Figure 6 and Figure 7 As shown, the specific flow path of natural gas during the negative pressure intake and booster propulsion process of the axial compressor 21 is as follows: The natural gas collected by the siphon assembly 3 first passes through the cylindrical cavity 231 in the inlet adapter 23, then enters the conical cavity 232 and flows through the impeller assembly 215 (driven by the motor in the compressor assembly 2) under the guidance of the outer wall of the guide shroud 216. It then enters the cavity of the end cap 213 and is evenly dispersed into multiple gas ports 219 before entering multiple compressor gas passages 218. After flowing through the multiple compressor gas passages 218, the natural gas enters the outlet cavity in the outlet adapter 22 through multiple openings 221, and then continues to be discharged towards the wellhead through the inner cable pipe 12.

[0072] It should be noted that the internal structure 212 within the outer casing 211 is a commonly used axial-flow compressor mechanism. This invention provides multiple compressor air passages 218 within its outer casing 211 to facilitate the formation and connection of an integrated air passage for the gas production tubing string (this integrated air passage will be described in detail below). The processing intensity of the compressor unit 2 for natural gas depends on multiple factors such as well depth, well pressure, and gas production capacity. The number of stages can be adjusted by increasing or decreasing them according to specific circumstances, making its application simple and convenient.

[0073] Furthermore, the siphon assembly 3 includes: a sleeve 31, a siphon 32, a storage pipe 33, a strip-shaped inlet 34, an internal gas intake inlet 35, and an external gas intake inlet 36;

[0074] The sleeve 31 is provided with a siphon tube 32 inside. One end of the siphon tube 32 is connected to the cylindrical cavity 231, and the outer wall of the other end is provided with a storage tube 33 located inside the sleeve 31.

[0075] The casing 31 has multiple strip-shaped openings 34 around its circumference. The siphon pipe 32 has multiple internal gas intake ports 35 evenly distributed on the pipe wall inside the storage pipe 33. The storage pipe 33 has multiple external gas intake ports 36 evenly distributed on its pipe wall.

[0076] In this embodiment, please refer to Figure 8 As shown, the area between the storage pipe 33 and the siphon pipe 32 is the gas collection chamber. When the siphon pipe group 3 is lowered to the designated position in the well (when the siphon section is located below the water accumulation layer in the well), the axial flow compressor 21 starts to work (the working process is to first draw in air under negative pressure and then push air under increased pressure).

[0077] Negative pressure intake process: The relative pressure drop between the inlet adapter 23 and the gas gathering chamber creates a pressure difference, which causes natural gas to be rapidly drawn from the natural gas gathering layer in the well into the siphon pipe 32 to complete the siphon operation. Then it flows through the inlet adapter 23 into the pressurization and lifting section.

[0078] Pressurization and thrusting process: The pressurization and thrusting operation of natural gas is completed in the pressurization and thrusting section (as described above).

[0079] It should be noted that the natural gas flows through the following paths as it enters the siphon pipe 32: the strip inlet 34, the external gas inlet 36, and the internal gas inlet 35. The siphon pipe 32 is made of 316L stainless steel continuous pipe with a diameter of less than 30mm. Both the siphon pipe 32 and the inlet adapter 23 are coated with solvent-free epoxy drag-reducing and anti-corrosion coating. This coating is applied using a vertical shaft installation and heating process, and the surface roughness can reach Ra0.5, which can effectively reduce damping and offset the flow resistance generated when the gas flows through the siphon section due to the reduced diameter.

[0080] For a preferred embodiment, please refer to Figure 8 As shown, the present invention can also uniformly open a plurality of inner vertical openings 8 at one end of the storage pipe 33 near the sensing sensor 4, and open a plurality of outer vertical openings 9 on the outside of the sensing sensor 4. The increase of inner vertical openings 8 and outer vertical openings 9 can improve the collection efficiency and collection stability of natural gas.

[0081] For a preferred embodiment, please refer to Figure 3 As shown, control valve 6 ( Figure 8 (Not shown in the image) is installed inside the siphon tube 32, and the separator 7 ( Figure 8(Not shown) It is installed on the outer wall of casing 31. Control valve 6 is a production control point. This invention includes an external master control unit that can remotely control the opening and closing of control valve 6. Specifically, when the siphon pipe assembly 3 is not lowered below the well's water layer, the external master control unit remotely controls control valve 6 to close. When the siphon pipe assembly 3 is lowered to the well's natural gas gathering layer, the external master control unit remotely controls control valve 6 to open. In this invention, control valve 6 can be an electromagnetic slide valve, a mechanical pressure slide valve, etc., to match the corresponding gas production channel opening method.

[0082] In this embodiment, the separator 7 is a process gate, which can be controlled by an external central control unit to isolate and connect the water layer and the natural gas gathering layer in the well. The separator 7 can also be an expandable barrier component; when it receives an opening command, its sealing element can expand radially to tightly fit the well wall of the gas production well 5, thereby physically isolating the water layer and the natural gas gathering layer. The separator 7 can also be other structural components, as long as they can achieve isolation and connection between the two areas. Specifically, when the siphon assembly 3 is lowered to the position of the natural gas gathering layer in the well, the external central control unit controls the separator 7 to unfold and isolate the water layer and the natural gas gathering layer. The separator 7 prevents the water layer in the well from sinking, avoiding affecting the stability of the natural gas gathering layer. The separator 7 acts as an upper water and lower gas barrier, greatly reducing the interference of the water layer in the well on the bottom-hole axial compressor 21 and gas production operations in the initial stage of gas production.

[0083] In this embodiment, the overall gas duct mentioned above, along the direction from the front end to the rear end of the gas collection pipe string, is composed of the area between the casing 31 and the storage pipe 33, the area between the storage pipe 33 and the siphon pipe 32, the internal area of ​​the siphon pipe 32, the inlet chamber area of ​​the inlet adapter 23, the impeller assembly 215, the gas port 219 inside the end cap 213, the compressor gas duct 218, the inner opening 221 of the outlet adapter 22, the outlet chamber inside the outlet adapter 22, the inner cable pipe 12, and the external gas collection mechanism, connected in sequence. It should be noted that the control valve 6 can control whether the overall gas duct is connected, and combined with the operation of the compressor unit 2, artificial intervention in the natural gas gas can be achieved.

[0084] Furthermore, a mining process based on a bottom-hole electric high-speed booster pump and a non-metallic cable-laying speed string includes the following steps:

[0085] In this embodiment, the staff needs to complete the installation of the gas sampling tubing string in advance. During installation, the sensor 4, siphon tube group 3, compressor group 2 and cable laying tube group 1 are connected in sequence from the front end to the rear end of the gas sampling tubing string. The gas sampling operation can only be started after the installation is completed and confirmed to be qualified.

[0086] S1 gas production tubing was inserted into the well;

[0087] S11: The assembled gas production tubing string is injected into the gas production well 5. The control valve 6 and the separator 7 are both closed at this time. When the front end of the gas production tubing string enters and exits the water layer in the well, the sensing sensor 4 sends a signal. The sensing sensor 4 is a sensor with gas sensing function. Through analysis, the thickness and depth of the water layer in the well can be determined.

[0088] S12: The gas production tubing string continues to descend, and is anchored when the siphon tube group 3 descends to the natural gas gathering layer in the well.

[0089] S13: Activate separator 7 to separate and isolate the water accumulation layer and the natural gas gathering layer in the well;

[0090] S2 Gas Gathering Channel Opening: Depending on the gas gathering conditions, different methods can be used to open control valve 6 to complete the opening of the gas gathering channel. Specifically, two different methods, S21 or S22, can be selected (not limited to S21 and S22, as long as the corresponding gas gathering conditions are met).

[0091] S21 Electrical Control Mode: In this mode, control valve 6 is an electromagnetic slide valve. Power can be easily supplied through the cable pipe electrical channel 15 in the cable pipe assembly 1 to achieve electrical control operation. After the gas sampling tubing string is positioned by descending, control valve 6 is slowly opened with the power supplied by the cable pipe assembly 1. At this time, the entire gas passage is fully connected, the gas sampling passage is opened, and the pressure inside the gas sampling tubing string changes. Gas sampling operation is started after the sensing sensor 4 sends a signal.

[0092] S22 Reverse Nitrogen Injection Method: In this method, control valve 6 is a mechanical pressure slide valve. After the gas production tubing is positioned at the bottom, nitrogen or compressed natural gas is injected in reverse from the wellhead through cable connection pipe 13 and inner cable pipe 12 directly to the bottom of the well. When the pressure exceeds the formation pressure, control valve 6 moves downward and is positioned. At this time, the entire gas channel is fully connected, and the gas production channel is opened. After the sensor 4 sends a signal, the gas injection operation is stopped, and then the gas production operation begins.

[0093] S3 gas production process: The compressor unit 2 is started to generate a pressure difference in the siphon pipe group 3, and then the natural gas in the natural gas gathering layer in the well is sucked into the siphon pipe group 3. Under the action of the compressor unit 2, it is pushed directly towards the wellhead through the water accumulation layer in the well. The natural gas is finally transported to the surface through the cable pipe group 1.

[0094] Specifically: When the axial compressor 21 is started, the pressure within the overall gas duct changes. At this time, a relative negative pressure is generated at the inlet adapter 23, creating a pressure difference within the siphon pipe 32. Natural gas located within the natural gas gathering layer will flow through the gathering chamber and into the siphon pipe 32 under the negative pressure suction operation of compressor unit 2, ultimately entering compressor unit 2. Subsequently, under the pressurization and thrusting operation of compressor unit 2, the natural gas is pushed upwards and transported to the surface through the inner cable pipe 12 and the cable connection pipe 13. Thus, direct collection of natural gas from the natural gas gathering layer can be achieved through artificial intervention without being affected by or pre-treating the water layer within the well.

[0095] Compared with traditional gas extraction methods, this invention is more proactive and direct, with simpler construction, less workload, smaller production fluctuations, and controllable gas extraction. This invention is a gas extraction process series device that establishes a multi-channel cable-laying pipe group 1 with downhole pressurization function and can be positioned at any location downhole. This invention breaks through existing production processes; it can be used alone or in combination with other common processes such as bubble drainage to improve natural gas recovery.

[0096] In practice, the axial compressor 21 is started, causing a change in pressure within the overall gas duct. At this point, a relative negative pressure is generated at the inlet adapter 23, creating a pressure difference within the siphon pipe 32. Natural gas located within the natural gas gathering layer will flow through the gathering chamber and into the siphon pipe 32 under the negative pressure suction operation of the compressor unit 2, ultimately entering the compressor unit 2. Subsequently, under the pressurization and thrusting operation of the compressor unit 2, the natural gas is pushed upwards and transported to the surface through the inner cable pipe 12 and the cable connection pipe 13. Thus, direct collection of natural gas from the natural gas gathering layer can be achieved through artificial intervention without being affected by or requiring pre-treatment of the well's water layer.

[0097] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A bottom-hole electric high-speed booster pump paired with a non-metallic cable-laying speed string, characterized in that: include: Cable laying pipe assembly (1), air compressor assembly (2), siphon assembly (3), sensor (4), control valve (6), and separator (7); One end of the cable-laying pipe assembly (1) is connected to an external gas collection mechanism, and the other end is connected to the compressor assembly (2). The end of the compressor assembly (2) away from the cable-laying pipe assembly (1) is connected to the siphon assembly (3). The end of the siphon assembly (3) away from the compressor assembly (2) is provided with the sensing sensor (4). The cable-laying pipe assembly (1), the air compressor assembly (2), the siphon assembly (3), and the sensing sensor (4) form a gas collection pipe string, which can move within the gas collection well (5). The siphon tube assembly (3) is equipped with the control valve (6), which can control the connection and blockage of the overall gas passage in the gas production tube string. The siphon tube assembly (3) is equipped with the separator (7) on its outer wall, which can isolate and connect the water accumulation layer and the natural gas gathering layer in the gas production well (5).

2. The bottom-hole electric high-speed booster pump with non-metallic cable-laying speed string according to claim 1, characterized in that: The cable laying pipe assembly (1) includes: an outer cable laying pipe (11), an inner cable laying pipe (12), and a cable laying connecting pipe (13). The outer cable conduit (11) contains the inner cable conduit (12), and the cable connecting pipe (13) is provided between the outer wall of the inner cable conduit (12) and the inner wall of the outer cable conduit (11). The inner wall of the cable connecting pipe (13) is in contact with the outer wall of the inner cable conduit (12), and the outer wall of the cable connecting pipe (13) is in contact with the inner wall of the outer cable conduit (11). The end of the cable-laying connecting pipe (13) away from the inner cable-laying pipe (12) is connected to the external gas collection mechanism, and the end of the inner cable-laying pipe (12) away from the cable-laying connecting pipe (13) is connected to the compressor unit (2).

3. The bottom-hole electric high-speed booster pump with non-metallic cable-laying speed string according to claim 2, characterized in that: A cable tube electrical channel (15) is formed between the inner wall of the outer cable tube (11), the outer wall of the inner cable tube (12), and the end of the cable connecting pipe (13) away from the external gas collection mechanism. A cable tube air passage (14) is formed inside the inner cable tube (12), and the cable tube air passage (14) is connected to the cable connecting pipe (13).

4. The bottom-hole electric high-speed booster pump with non-metallic cable-laying speed string according to claim 2, characterized in that: The compressor unit (2) includes: an axial compressor (21), an outlet adapter (22), and an inlet adapter (23). One end of the axial compressor (21) is connected to the inner cable tube (12) through the outlet adapter (22), and the other end is connected to the siphon tube group (3) through the inlet adapter (23).

5. The bottom-hole electric high-speed booster pump with non-metallic cable-laying speed string according to claim 4, characterized in that: The axial compressor (21) includes: a housing (211), a body (212), an end cover (213), a rotor shaft (214), an impeller assembly (215), a flow guide (216), an inner support sleeve (217), a compressor air passage (218), and an air inlet (219). The outer casing (211) is connected to the impeller assembly (215) at one end via the end cover (213), and the end of the impeller assembly (215) away from the end cover (213) is connected to the air inlet adapter (23). The housing (211) contains the body (212), which is connected to the impeller assembly (215) via the rotor shaft (214) and the inner support sleeve (217). The inner support sleeve (217) is provided with the flow guide (216) at one end away from the rotor shaft (214). The outer casing (211) has multiple compressor air passages (218) circumferentially located outside the body (212). The end cap (213) is a cavity with multiple air ports (219) circumferentially located. The multiple air ports (219) are respectively connected to the multiple compressor air passages (218).

6. The bottom-hole electric high-speed booster pump with non-metallic cable-laying speed string according to claim 5, characterized in that: The air inlet adapter (23) includes: an air inlet chamber; The air intake chamber is located inside the air intake adapter (23). The air intake chamber includes a cylindrical cavity (231) and a conical cavity (232). The conical cavity (232) is shaped to match the flow guide (216). The end of the conical cavity (232) away from the cylindrical cavity (231) is connected to the cavity of the end cap (213). The end of the cylindrical cavity (231) away from the conical cavity (232) is connected to the siphon tube assembly (3).

7. The bottom-hole electric high-speed booster pump with non-metallic cable-laying speed string according to claim 5, characterized in that: The air outlet adapter (22) includes: an air outlet chamber; The air outlet chamber is located inside the air outlet adapter (22). Multiple openings (221) are provided around the circumference of the air outlet chamber. Each of the multiple openings (221) is connected to a corresponding air compressor passage (218). The end of the air outlet chamber away from the opening (221) is connected to the inner cable tube (12).

8. The bottom-hole electric high-speed booster pump with non-metallic cable-laying speed string according to claim 6, characterized in that: The siphon assembly (3) includes: a sleeve (31), a siphon (32), a storage pipe (33), a strip-shaped opening (34), an internal gas intake opening (35), and an external gas intake opening (36); The sleeve (31) is provided with a siphon tube (32) inside. One end of the siphon tube (32) is connected to the cylindrical cavity (231), and the outer wall of the other end is provided with the storage tube (33) located inside the sleeve (31). The sleeve (31) has a plurality of strip-shaped openings (34) on its circumference. The siphon pipe (32) is located inside the pipe wall of the storage pipe (33) and has a plurality of internal gas intake ports (35) evenly provided. The storage pipe (33) has a plurality of external gas intake ports (36) evenly provided on its pipe wall.

9. A mining process, based on the bottom-hole electric high-speed booster pump and non-metallic cable-laying speed string as described in any one of claims 1-8, characterized in that: It includes the following steps: S1 gas production tubing was inserted into the well; S11: Inject the assembled gas production tubing string into the gas production well (5). The control valve (6) and the separator (7) are both closed at this time. When the front end of the gas production tubing string enters and exits the water layer in the well, the sensor (4) sends a signal. The thickness and depth of the water layer in the well can be determined by analysis. S12: The gas production tubing string continues to descend, and is anchored when the siphon tube group (3) descends to the natural gas gathering layer in the well. S13: Activate the separator (7) to separate the water accumulation layer in the well from the natural gas gathering layer; S2 Gas Collection Channel Opening: According to the gas collection conditions, different methods are selected to control the valve (6) to open, thus completing the opening of the gas collection channel; S3 gas production process: The compressor unit (2) is started to generate a pressure difference in the siphon pipe group (3), and then the natural gas in the natural gas gathering layer in the well is sucked into the siphon pipe group (3). Under the action of the compressor unit (2), it is pushed directly towards the wellhead through the water accumulation layer in the well. The natural gas is finally transported to the surface through the cable laying pipe group (1).

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