A gas well downhole jet flow enhanced multi-stage gas-liquid high-efficiency separation device

Abstract

The application relates to a gas well downhole jet flow enhanced multi-stage gas-liquid high-efficiency separation device, which comprises a gas-liquid separation structure and a gas-liquid diversion structure. The gas-liquid separation structure comprises a lower outer pipe and an inner pipe, the lower outer pipe and the inner pipe are coaxially arranged, the upper end of the lower outer pipe and the lower end of the inner pipe are provided with liquid inlets, a first spiral flow channel, a drainage inverted cone, a second spiral flow channel and a drainage cone pipe are arranged in the inner pipe. The gas-liquid diversion structure comprises an upper outer pipe, a pump outer pipe, a fixing ring, a bypass flow channel and a bridge type channel, the upper outer pipe and the pump outer pipe are coaxially arranged, the upper end of the bridge type channel is connected with the upper outer pipe, the bypass flow channel is arranged below the bridge type channel and extends into the inner sleeve of the fixing ring, the annular space between the bypass flow channel and the inner sleeve of the fixing ring is a flow guide cavity and is tapered, and the flow guide cavity is an annular gap between the bypass flow channel and the upper end of the inner sleeve of the fixing ring. The gas-liquid separated by the device is discharged separately, the gas phase is sprayed and discharged under the action of downhole pressure, and the liquid phase is pumped out, so that the gas phase does not contact the pump body.

Description

Technical Field

[0001] This invention relates to a separation device used in the field of high-pressure downhole gas-liquid separation, specifically a device capable of achieving efficient separation of oil and gas two-phase media in a confined downhole space, and a gas well downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device. Background Technology

[0002] With the continuous development of gas well extraction technology in my country, downhole gas-liquid separation is a crucial step in extraction and processing. However, increased water content makes it more difficult to drain fluid from gas wells for gas production, necessitating intensified drainage efforts to achieve production targets and increase output. This requires greater investment in technology and equipment, thus increasing production costs.

[0003] To address the problem of low gas-liquid separation efficiency in gas wells and the difficulty in achieving sufficient separation downhole, technicians have proposed several solutions. As shown in patent document 1, CN201510683020.8, this solution utilizes blades on a screw rod for gas-liquid separation, causing the gas-liquid mixture to flow to the separation joint via the screw rod inside the cylinder, thereby achieving gas-liquid separation. However, under this solution, the separated gas phase still carries a small amount of liquid droplets, and only one gas-liquid separation can be performed; further gas-liquid separation cannot be performed on the separated gas phase. Therefore, the gas-liquid separation efficiency is not high.

[0004] As shown in Patent Document 2, CN201621062438.3, the gas separated from the gas-liquid separation no longer comes into contact with the produced mixture, but a small amount of gas still enters the oil pump, which will affect the working efficiency of the oil pump and cause damage to the oil pump over a long period of time. Summary of the Invention

[0005] The purpose of this invention is to provide a gas well downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device. This gas well downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device is used to solve the problem of low separation efficiency of existing gas-liquid separation devices, or the problem that a small amount of gas still enters the oil pump after gas-liquid separation, affecting the working efficiency of the oil pump.

[0006] The technical solution adopted by this invention to solve its technical problem is as follows: This downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device for gas wells includes a gas-liquid separation structure and a gas-liquid diversion structure. The gas-liquid separation structure is located below the gas-liquid diversion structure. The gas-liquid separation structure includes a lower outer pipe and an inner pipe, which are coaxially arranged. Liquid inlets are provided at the upper ends of both the lower outer pipe and the inner pipe. A primary spiral flow channel and a secondary spiral flow channel are provided in the inner pipe. The upper end of the primary spiral flow channel is connected to a guide cone, and the upper end of the secondary spiral flow channel is connected to a guide cone pipe. The gas-liquid diversion structure includes an upper outer pipe, a pump outer pipe, a fixing ring, a bypass flow channel, and a bridge-type channel. The upper outer pipe and the pump outer pipe are coaxially arranged, and the fixing ring is threadedly connected to the upper end of the lower outer pipe. The fixed ring has an annular groove in its middle, forming a two-layered cylinder. The inner layer is an inner sleeve, and the upper part of the fixed ring is a single-layered cylinder with only an outer wall. The upper end of the outer wall of the fixed ring is connected to a bridge-type channel, and the upper end of the bridge-type channel is connected to an upper outer pipe. A screw pump is installed inside the pump outer pipe. The bypass channel is a tapered tube with several bypass channel openings at the lower part. The bypass channel is located below the bridge-type channel and extends into the inner sleeve of the fixed ring. The annular space between the bypass channel and the inner sleeve of the fixed ring is a guide cavity, which is tapered. The guide cavity is located between the bypass channel and the inner sleeve of the fixed ring. The gap between the ports is annular. The mixture containing gas and liquid phases first enters the gas-liquid separation structure for secondary gas-liquid separation. The separated gas phase moves upward in the bypass channel, enters the annular gas channel between the upper outer pipe and the pump outer pipe through the bridge channel and flows out. The liquid phase mixed with a small amount of gas phase moves upward along the guide cavity under the pressure difference provided by the screw pump. The gas phase mixed in the liquid phase gathers into the bypass channel from the opening below the bypass channel. The liquid phase separated again is sprayed out from the annular gap and flows out from the pump outer pipe under the suction of the screw pump through the bridge channel.

[0007] In the above scheme, the bridge-type channel is a cylindrical body with an internal partition, which divides the cylindrical body into an air chamber and an oil chamber. The air chamber is connected to the bypass channel through a channel connection. The air chamber is connected to the upper annular opening of the bridge-type channel in the oil chamber wall through openings on both sides of the center of the bridge-type channel. The upper annular opening of the bridge-type channel is connected to the annular air passage. The air chamber wall has a lower annular opening of the bridge-type channel, which is connected to the oil chamber. The oil chamber has an upper central opening of the bridge-type channel at the top, which is connected to the outlet pipe through the upper central opening of the bridge-type channel. The oil chamber is connected to the pipe pump threadedly through the upper central opening of the bridge-type channel. The pipe pump is connected to the screw pump threadedly. The outer wall diameter of the middle part of the bridge-type channel is equal to the outer wall diameter of the fixed ring. The outer wall of the top of the oil chamber of the bridge-type channel has external threads, and the air chamber wall of the bridge-type channel has external threads.

[0008] In the above scheme, the lower end of the inner tube and the lower end of the lower outer tube are respectively threaded to the inner and outer tubes, and the lower end of the inner and outer tube connection is threaded to the oil pipe coupling; the lower end of the first-stage spiral flow channel is threaded to the upper end of the inner and outer tube connection, and the upper end of the first-stage spiral flow channel is threaded to the lower end of the diversion cone.

[0009] In the above scheme, the upper end of the inner tube is threaded to a spiral connection, the upper end of the spiral connection is threaded to a secondary spiral flow channel connection, and the upper end of the secondary spiral flow channel is threaded to a flow-guiding cone tube.

[0010] In the above scheme, the inner diameter of the lower end of the fixing ring is equal to the inner diameter of the inner tube. The lower end of the fixing ring has an external thread, and the upper end of the lower outer tube has an internal thread. The fixing ring and the outer tube are connected by threads, and the lower end of the fixing ring closes the annular space between the lower outer tube and the inner tube.

[0011] In the above scheme, the bypass channel openings at the bottom of the bypass channel are evenly distributed in a ring shape, and are divided into 5 layers from top to bottom; the upper end of the bypass channel is connected to the lower end of the channel by a thread; the upper end of the channel connection is connected to the lower end of the bridge channel by a thread.

[0012] In the above scheme, the lower end of the upper outer pipe is connected to the bridge channel by a thread, and the lower end of the pump outer pipe is connected to the inner wall of the bridge channel outlet pipe by a thread.

[0013] The present invention has the following beneficial effects: 1. This invention performs primary cyclone separation on a gas-containing liquid mixture, then allows the gas phase containing a small amount of liquid to enter the secondary separation stage through a guide cone, thereby achieving secondary gas filtration. Furthermore, the secondary gas-liquid separation and cyclone separation do not interfere with each other, achieving both high separation efficiency and rapid separation, and is suitable for the high flow rate characteristics inside the cyclone separator.

[0014] 2. This invention innovatively proposes a screw pump gas well production process technology, which achieves efficient separation of gas and liquid two-phase media by adding a high-precision gas-liquid cyclone separator to a conventional screw pump, greatly reducing the occurrence of water flooding problems, enhancing the adaptability of screw pump equipment in gas wells, and realizing the combined use of separation, diversion and pump body.

[0015] 3. The diversion structure proposed in this invention utilizes its special structure to separate and discharge the gas and liquid phases. This allows the gas phase to be ejected under downhole pressure, while the liquid phase is extracted under the pressure difference provided by the screw pump. This ensures gas-liquid separation efficiency while preventing the gas phase from contacting the pump body, thus improving the pump's service life and enhancing the overall compatibility of the device.

[0016] 4. The separation structure proposed in this invention can be integrated into the narrow space of the wellbore, achieving efficient separation and realizing the purpose of collecting the liquid phase and discharging the gas phase. Moreover, the two-stage cyclone device involved is arranged in a very small space, which not only improves the gas-liquid separation efficiency, but also enhances the practicality of the equipment. It is an integrated downhole two-phase high-efficiency separation device that combines aggregation and cyclone technology, which can achieve efficient separation of gas and liquid two-phase media in a limited space and improve the economics of gas well production.

[0017] 5. The internal structure of the bridge-type channel of the present invention separates the gas and liquid phases, so that the gas phase does not come into contact with the pump body, while the gas and liquid phases are extracted by the pressure difference.

[0018] 6. This invention utilizes a spiral flow channel structure within the separation chamber to separate gas and liquid. Simultaneously, the arrangement of two-stage spiral flow channels enables further gas-liquid separation, achieving two-stage separation. Furthermore, the top of the guide cone at the upper end of the perforated spiral flow channel has a small-diameter opening, reducing the gas flow diameter and increasing the flow velocity. This further concentrates a small portion of the gas phase around the guide cone, allowing for jet discharge of the gas phase and improving separation efficiency. Simultaneously, the gas phase extracted by the pressure difference of the screw pump does not contact the pump body, extending the pump's service life. Attached Figure Description

[0019] Figure 1 (a) is an appearance drawing of the present invention; Figure 1 (b) is a cross-sectional view of the present invention.

[0020] Figure 2 (a) is an external view of the gas-liquid separation structure; Figure 2 (b) is a cross-sectional view of the gas-liquid separation structure.

[0021] Figure 3 This is an exploded view of a gas-liquid separation structure.

[0022] Figure 4 (a) is an external view of the gas-liquid separation structure; Figure 4 (b) is a cross-sectional view of the gas-liquid split structure.

[0023] Figure 5 This is an exploded view of the gas-liquid separation structure.

[0024] Figure 6 (a) is an exterior view of the bridge-type passageway; Figure 6 (b) is a top view of the bridge-type passageway; Figure 6 (c) is a front sectional view of the bridge-type passageway; Figure 6 (d) is the right-side sectional view of the bridge passage.

[0025] In the diagram: 101-oil pipe coupling, 102-lower outer pipe, 1021-outer pipe inlet, 103-connection of inner and outer pipes, 104-inner pipe, 1041-inner pipe inlet, 105-first-stage spiral flow channel, 1051-first-stage spiral flow channel separation chamber, 106-draining cone, 107-spiral connection, 108-second-stage spiral flow channel, 1081-second-stage spiral flow channel separation chamber, 109-draining cone, 1091-draining cone 201-Fixing ring, 202-Bridge channel, 2021-Bridge channel lower annular opening, 2022-Bridge channel center openings on both sides, 2023-Bridge channel upper annular opening, 2024-Bridge channel upper center opening, 203-Bypass channel, 2031-Bypass channel opening, 204-Channel connection, 205-Upper outer pipe, 206-Pump connection, 207-Screw pump, 208-Pump outer pipe. Detailed Implementation

[0026] The invention will be further described below with reference to the accompanying drawings: This downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device for gas wells includes a gas-liquid separation structure with a tubing coupling 101 and a gas-liquid diversion structure with a screw pump 207. It enables the separation of gas-containing mixtures into two-phase gas and liquid media with a small footprint. After separation, the gas phase is discharged to the external space of the equipment, improving the service life of other operating equipment. At the same time, it completes the pre-separation of produced fluid, indirectly improving the gas well recovery rate and reducing the energy consumption of the subsequent separation system.

[0027] The gas-liquid separation structure includes an inner and outer pipe connection 103, a lower outer pipe 102, an inner pipe 104, a primary spiral flow channel 105, a primary spiral flow channel separation chamber 1051, a guide cone 106, a spiral connection 107, a secondary spiral flow channel 108, a guide cone 109, a guide cone opening 1091, and a secondary spiral flow channel separation chamber 1081. The spiral flow channel and the guide cone 109 both have a hollow structure. Liquid inlets are provided on the inner pipe 104 and the lower outer pipe 102. The outer pipe inlet 1021 at the upper end of the lower outer pipe 102 is provided to ensure that the liquid phase can accumulate sufficiently from top to bottom within the inner and outer pipe cavities, thus facilitating the next separation step. The upper end of the tubing coupling 101 is connected to the lower end of the inner and outer tubes 103 via a threaded connection; the inner tube 104 and the lower outer tube 102 are connected to the upper end of the inner and outer tubes 103 via a threaded structure; the lower end of the hollow primary spiral flow channel 105 is connected to the upper end of the inner and outer tubes 103 via a threaded connection with an opening; the upper end of the hollow primary spiral flow channel 105 is connected to the lower end of the drainage cone 106 via a threaded connection; the lower end of the spiral link 107 is connected to the upper end of the inner tube 104 via a threaded structure; the upper end of the spiral link 107 is provided with a threaded structure and connected to the secondary spiral flow channel 108; the upper end of the secondary spiral flow channel 108 is connected to the lower end of the drainage cone 109 via a threaded connection.

[0028] During operation, a mixture containing both gas and liquid phases enters the inner and outer pipe cavities through the outer pipe inlet 1021 around the upper end of the lower outer pipe 102. Then, the gas-liquid mixture enters the gas-liquid separation section through the inner pipe inlet 1041 around the lower end of the inner pipe 104. After centrifugal acceleration by the hollow primary spiral flow channel 105, the gas phase is distributed on the outer wall of the guiding inverted cone 106, while the liquid phase, carrying some unseparated gas phase, resides on the outer layer near the inner wall of the primary spiral flow channel separation cavity 1051. Next, the liquid phase further accumulates along the inner wall of the spiral link 107 and flows towards the secondary spiral flow channel 108, while the gas phase flows along the central opening of the spiral link 107 towards the secondary spiral flow channel 108, continuing the process... The gas phase flows from the center of the secondary spiral channel 108 to the opening 1091 of the guide cone tube, which reduces the diameter of the gas phase flow and increases the flow velocity. At the same time, it can further gather a small portion of the gas phase around the guide cone tube, realizing the jet discharge of the gas phase to the next stage. The gas and liquid phases separated by the spiral link 107 are further accelerated and separated by the secondary spiral channel 108, so that the gas phase is located inside the separation chamber 1081 of the secondary spiral channel and flows further to the outer wall of the guide cone tube 109, where it further converges with the gas phase discharged from the opening 1091 of the guide cone tube. Meanwhile, the liquid phase flows along the inner wall of the separation chamber 1081 of the secondary spiral channel 108 to the next stage on the outside of the secondary spiral channel 108, further completing the gas-liquid separation. More specifically: the gas-liquid separation structure is divided into a primary gas-liquid separation module and a secondary gas-liquid separation module according to its function. The specific components involved in the function of each gas-liquid separation module and the connection relationships between the components are as follows: The primary gas-liquid separation module includes an inner and outer pipe connection 103, a lower outer pipe 102, an inner pipe 104, a primary spiral flow separation chamber 1051, a primary spiral flow channel 105, and a flow-guiding inverted cone 106; wherein the primary spiral flow channel 105 adopts a hollow structure, with liquid inlets 1021 distributed around the upper end of the lower outer pipe 102 and liquid inlets 1041 distributed around the lower end of the inner pipe 104 in an alternating distribution. The upper threaded structure of the inner and outer tube connection 103 is connected to the lower outer tube 102 and inner tube 104. A threaded hole is opened at the center of the upper end of the inner and outer tube connection 103 and is threadedly connected to the lower end of the first-stage spiral flow channel 105. The threaded structure at the lower end of the guide cone 106 is connected to the threaded hole at the upper end of the first-stage spiral flow channel 105. The mixed liquid entering from the outer tube inlet 1021 flows through the inner and outer tube cavities and into the vortex first-stage spiral flow channel separation chamber 1051 through the inner tube inlet 1041. After the mixed liquid is accelerated and separated by the first-stage spiral flow channel 105, the centrifugal force on the gas phase is less than that on the liquid phase. The gas phase carries a small amount of liquid phase and flows to the next stage in the guide cone 106. Most of the liquid phase gathers on the inner wall of the inner tube 104 and flows to the next stage, completing the first-stage separation.

[0029] The secondary gas-liquid separation module includes a spiral link 107, a secondary spiral flow channel 108, a guide cone tube 109, a guide cone tube opening 1091, and a secondary spiral flow channel separation chamber 1081. The lower end of the spiral link 107 is threaded to the upper end of the inner tube 104. A threaded hole is located at the center of the upper end of the spiral link 107, which is threaded to the lower end of the secondary spiral flow channel 108. The wall thickness of the spiral link 107 is the same as that of the inner tube 104. The center of the upper end of the secondary spiral flow channel 108 is threaded to the lower end of the guide cone tube 109, which is a hollow structure. The liquid phase further accumulates along the inner wall of the spiral link 107 and flows towards the secondary spiral flow channel 108, while the gas phase flows along the central opening of the spiral link 107 towards the secondary spiral flow channel 108, and then continues to flow from the center of the secondary spiral flow channel 108 towards the guide cone tube opening 1091. The smaller diameter of the flow cone tube opening 1091 reduces the gas flow diameter, increasing the flow velocity and further concentrating a small portion of the gas phase around the flow cone tube. This allows the gas phase to be jetted out to the next stage. The gas and liquid phases separated by the spiral link 107 are further accelerated and separated by the secondary spiral channel 108, causing the gas phase to be located inside the secondary spiral channel separation chamber 1081 and flow further towards the outer wall of the flow cone tube 109, where it further converges with the gas phase discharged from the flow cone tube opening 1091. Meanwhile, the liquid phase flows along the inner wall of the secondary spiral channel separation chamber 1081 outside the secondary spiral channel 108 to the next stage, further completing the gas-liquid separation. The gas-liquid splitting module of this invention includes a fixed ring 201, a bypass channel 203, a bridge-type channel 202, a channel connection 204, a deep well screw pump 207, an upper outer pipe 205, a pump outer pipe 208, and a pipe-pump connection 206. The inner wall of the fixed ring 201 has the same thickness as the inner wall of the inner pipe 104, and its outer wall has the same thickness as the outer wall of the outer pipe 102. The upper end of the fixed ring 201 has a lead-out pipe of a certain thickness. The bypass channel 203 has a tapered pipe wall, and there are evenly distributed openings in the annular position below it. The middle part of the bridge-type channel 202 is connected to the fixed ring 207. 1. The outer wall thickness is uniform; both ends of the bridge-type channel 202 have threads, and there is a section of outlet pipe at the upper end; the lower end of the fixing ring 201 is threaded to the inner side of the upper end of the outer tube 102; the upper end of the bypass channel 203 is threaded to the lower end of the channel connection 204; the lower end of the channel connection 204 is threaded to the center opening of the bridge-type channel 202; the lower end of the upper outer tube 205 is threaded to the upper end of the bridge-type channel 202; the lower end of the pipe pump connection 206 is threaded to the opening at the upper end of the bridge-type channel 202, and the upper end of the pipe pump connection 206... The lower end of the screw pump 207 is connected by a thread; the lower end of the pump outer pipe 208 is connected by a thread to the inner side of the upper end of the bridge channel 202. During operation, the gas phase after primary and secondary separation flows into the center of the bypass channel 203 through the center opening of the guide cone 109. The liquid phase mixed with a small amount of gas phase from the previous stage flows to the next stage through the outer annular cavity of the bypass channel 203 under the pressure difference provided by the screw pump. The opening 2031 below the bypass channel further aggregates the gas phase mixed in the liquid phase with the gas phase flowing down from the center opening of the guide cone 109. The gas phase then enters from the lower inlet of the bridge channel 202, which facilitates gas-liquid separation. The gas phase then flows in from the center of the lower end of the bridge channel 202 and flows through the openings on both sides of the center to the two side channels at the lower end of the bridge channel 202. The liquid phase flows in through the annular opening at the lower end of the bridge channel 202 and flows out to the center. The screw pump 207 provides power to the entire device and draws the liquid phase flowing out from the center of the bridge channel 202 to the pump outer pipe 208 to transport it to the ground. The separated gas phase flows out through the gap between the upper outer pipe 205 and the pump outer pipe 208 to the next structure.

[0030] like Figure 1As shown, the present invention is placed vertically inside the downhole pipeline, ensuring that the tubing coupling 101 is at the lowest end, and each part is connected upwards in sequence according to the corresponding connection method. During operation, the gas-containing liquid phase enters the inner and outer pipe cavities from the outer pipe inlet 1021. The mixture flows from top to bottom in the inner and outer pipe cavities, and enters the first-stage spiral flow separation chamber 1051 from the inner pipe inlet 1041. After being centrifugally accelerated by the hollow first-stage spiral flow channel 105, the liquid phase is guided by the inverted flow cone 106 to distribute on the inner wall of the first-stage spiral flow separation chamber 1051. The gas phase carries a small amount of liquid phase and flows upwards at the center of the inverted flow cone 106. Then, the liquid phase further accumulates along the inner wall of the spiral link 107 and flows to the second-stage spiral flow channel 108, while the gas phase flows to the second stage along the central opening of the spiral link 107. The spiral flow channel 108 continues the flow from the center of the secondary spiral flow channel 108 to the opening 1091 of the guide cone tube. The smaller diameter of the opening 1091 of the guide cone tube reduces the gas flow diameter, increasing the flow velocity and further concentrating a small portion of the gas phase around the guide cone tube. This allows the gas phase to be jetted out to the next stage. The gas and liquid phases separated by the spiral link 107 are further accelerated and separated by the secondary spiral flow channel 108, causing the gas phase to be located inside the separation chamber 1081 of the secondary spiral flow channel. It then flows further towards the outer wall of the guide cone tube 109, where it further converges with the gas phase discharged from the opening 1091 of the guide cone tube. The liquid phase, however, remains in the secondary spiral flow channel 108. The outer side of the first-stage spiral channel 108 flows to the next stage along the inner wall of the second-stage spiral channel separation chamber 1081, further completing gas-liquid separation. The gas phase after the first and second separations flows into the center of the bypass channel 203 through the center opening of the guide cone tube 109. The liquid phase mixed with a small amount of gas phase from the previous stage flows to the next stage along the outer annular cavity of the bypass channel 203 under the pressure difference provided by the screw pump. The opening 2031 below the bypass channel further aggregates the gas phase mixed in the liquid phase with the gas phase flowing down from the center opening of the guide cone tube, and then enters together from the lower inlet of the bridge channel 202, which is conducive to gas-liquid separation. Next, the gas phase flows in from the center of the bridge channel 202, and flows through the openings 2022 on both sides of the center of the bridge channel 202 to the openings 2023 on both sides of the upper end, and flows out through the outer ring of the bypass channel 203. The liquid phase flows in through the annular opening 2021 at the lower part of the bridge channel, and converges to the center and is discharged through the upper opening 2024. The screw pump 207 draws the liquid phase gathered in the bridge channel 202 into the pump outer pipe 208 cavity by the pressure difference, while the gas phase flows into the upper outer pipe 205 and the pump outer pipe 208 cavity. Finally, the gas and liquid phases are connected to the next part of the device respectively. The appearance and cross-sectional view of the gas-liquid separation structure are as follows. Figure 2As shown, during operation, a mixture containing both gas and liquid phases enters the inner and outer pipe cavities through the outer pipe inlet 1021 around the upper end of the lower outer pipe 102. Then, the gas-liquid mixture flows from top to bottom through the inlet 1041 around the lower end of the inner pipe 104 into the gas-liquid separation section. After centrifugal acceleration by the hollow primary spiral flow channel 105, the gas phase is distributed on the outer layer of the inverted cone 106, while the liquid phase, carrying a small amount of gas, resides on the inner wall of the primary spiral flow separation chamber 1051. Next, the liquid phase further accumulates along the inner wall of the spiral link 107 and flows towards the secondary spiral flow channel 108, while the gas phase flows along the central opening of the spiral link 107 towards the secondary spiral flow channel 108, continuing to flow from the center of the secondary spiral flow channel 108 towards the drainage section. The cone tube opening 1091 has a small diameter, which reduces the gas flow diameter and increases the flow velocity. This allows for the further accumulation of a small portion of the gas phase around the periphery of the cone tube, enabling the gas phase to be jetted out to the next stage. The gas and liquid phases separated by the spiral link 107 are further accelerated and separated by the secondary spiral channel 108. This causes the gas phase to be located inside the secondary spiral channel separation chamber 1081 and flow further towards the outer wall of the cone tube 109, where it further converges with the gas phase discharged from the cone tube opening 1091. Meanwhile, the liquid phase flows along the inner wall of the secondary spiral channel separation chamber 1081 outside the secondary spiral channel 108 to the next stage, further completing the gas-liquid separation. An exploded view of the gas-liquid separation structure is shown below. Figure 3 As shown. The external view and cross-sectional view of the gas-liquid splitting structure are as follows. Figure 4 As shown in (a) and (b), the gas phase after primary and secondary separation flows along the center of the guide cone 109 to the central opening of the bypass channel 203. The liquid phase, mixed with a small amount of gas phase from the previous stage separation, flows to the next stage along the outer annular cavity of the bypass channel 203 under the pressure difference provided by the screw pump. The opening 2031 below the bypass channel further aggregates the gas phase mixed in with the liquid phase and the gas phase flowing down from the central opening of the guide cone, and then enters together from the lower inlet of the bridge channel 202, which is conducive to gas-liquid separation. Then the gas phase flows from the center of the bridge channel 202. The liquid phase flows in from the center of the bridge channel through openings 2022 on both sides, and then flows out through the annular openings 2023 at the upper end of the bridge channel. The liquid phase flowing through the outer ring of the bypass channel 203 flows in through the annular opening 2021 at the lower part of the bridge channel, converges at the center, and is discharged through the central opening 2024 at the upper end of the bridge channel. The screw pump 207 draws the liquid phase collected in the bridge channel 202 into the outer pump pipe 208 under pressure difference. The gas phase flows into the upper outer pipe 205 and the outer pump pipe 208. Finally, the gas and liquid phases are connected to the next part of the device. An exploded view of the gas-liquid separation structure is shown below. Figure 5 As shown. The exterior view, top view, and sectional view of the bridge-type passage are as follows. Figure 6As shown in (a), (b), (c), and (d), the gas phase flows in from the center of the bridge channel 202, flows through the openings 2022 on both sides of the center of the bridge channel, and is discharged from the annular opening 2023 at the upper end of the bridge channel. The liquid phase, passing through the outer ring of the bypass channel 203, flows in through the annular opening 2021 at the lower end of the bridge channel 202, converges to the center, and is discharged from the central opening 2024 at the upper end of the bridge channel.

[0031] This invention has a simple overall structure and can achieve efficient separation of gas and liquid two-phase media in a confined space downhole. It has a wide range of applications. This device combines swirl technology and coalescence technology to achieve efficient separation of two-phase media. Through innovative structural layout, it rationally handles the two media after separation, has extremely high applicability, greatly improves the recovery rate of gas wells, enhances the economy of the production system, and reduces the operating pressure of subsequent separation equipment.

Claims

1. A downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device for gas wells, characterized in that: The downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device for gas wells includes a gas-liquid separation structure and a gas-liquid diversion structure. The gas-liquid separation structure is located below the gas-liquid diversion structure. The gas-liquid separation structure includes a lower outer pipe and an inner pipe, which are coaxially arranged. Both the upper end of the lower outer pipe and the lower end of the inner pipe have liquid inlets. The inner pipe contains a primary spiral flow channel and a secondary spiral flow channel. The upper end of the primary spiral flow channel is connected to a guide cone, and the upper end of the secondary spiral flow channel is connected to a guide cone pipe. The gas-liquid diversion structure includes an upper outer pipe, a pump outer pipe, a fixing ring, a bypass flow channel, and a bridge-type channel. The upper outer pipe and the pump outer pipe are coaxially arranged, and the fixing ring is threadedly connected to the upper end of the lower outer pipe. The fixed ring has an annular groove in its middle, forming a two-layered cylinder. The inner layer is an inner sleeve, and the upper part of the fixed ring is a single-layered cylinder with only an outer wall. The upper end of the outer wall of the fixed ring is connected to a bridge-type channel, and the upper end of the bridge-type channel is connected to an upper outer pipe. A screw pump is installed inside the pump outer pipe. The bypass channel is a tapered tube with several bypass channel openings at the lower part. The bypass channel is located below the bridge-type channel and extends into the inner sleeve of the fixed ring. The annular space between the bypass channel and the inner sleeve of the fixed ring is a guide cavity, which is tapered. The guide cavity is located between the bypass channel and the inner sleeve of the fixed ring. The gap between the ports is annular. The mixture containing gas and liquid phases first enters the gas-liquid separation structure for secondary gas-liquid separation. The separated gas phase moves upward in the bypass channel, enters the annular gas channel between the upper outer pipe and the pump outer pipe through the bridge channel and flows out. The liquid phase mixed with a small amount of gas phase moves upward along the guide cavity under the pressure difference provided by the screw pump. The gas phase mixed in the liquid phase gathers into the bypass channel from the opening below the bypass channel. The liquid phase separated again is sprayed out from the annular gap and flows out from the pump outer pipe under the suction of the screw pump through the bridge channel.

2. The gas well downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device according to claim 1, characterized in that: The bridge-type channel is a cylindrical body with internal partitions, dividing the body into an air chamber and an oil chamber. The air chamber is connected to a bypass channel via a channel connection. The air chamber is connected to the upper annular opening of the bridge-type channel within the oil chamber wall via openings on both sides of the center of the bridge-type channel. The upper annular opening of the bridge-type channel is connected to the annular air passage. The air chamber wall has a lower annular opening of the bridge-type channel, which is connected to the oil chamber. The oil chamber has an upper central opening of the bridge-type channel at the top, which is connected to an outlet pipe. The oil chamber is also connected to a threaded connection to a pipe pump via the upper central opening of the bridge-type channel. The pipe pump is threaded to a screw pump. The outer wall diameter of the middle section of the bridge-type channel is equal to the outer wall diameter of the fixed ring. The outer wall of the top of the oil chamber of the bridge-type channel has external threads, and the air chamber wall of the bridge-type channel also has external threads.

3. The gas well downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device according to claim 2, characterized in that: The lower end of the inner tube and the lower end of the lower outer tube are respectively threaded to the inner and outer tubes. The lower end of the inner and outer tube connection is threaded to the oil pipe coupling. The lower end of the first-stage spiral flow channel is threaded to the upper end of the inner and outer tube connection. The upper end of the first-stage spiral flow channel is threaded to the lower end of the inverted conical flow guide.

4. The gas well downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device according to claim 2, characterized in that: The upper end of the inner tube is threaded to a spiral connection, the upper end of the spiral connection is threaded to a secondary spiral flow channel connection, and the upper end of the secondary spiral flow channel is threaded to a flow-guiding cone tube.

5. The gas well downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device according to claim 4, characterized in that: The inner diameter of the lower end of the retaining ring is equal to the inner diameter of the inner tube. The lower end of the retaining ring has an external thread, and the upper end of the lower outer tube has an internal thread. The retaining ring and the outer tube are connected by threads. The lower end of the retaining ring closes the annular space between the lower outer tube and the inner tube.

6. The gas well downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device according to claim 5, characterized in that: The bypass channel openings at the bottom are evenly distributed in a ring shape, divided into five layers from top to bottom; the upper end of the bypass channel is connected to the lower end of the channel by a thread; the upper end of the channel is connected to the lower end of the bridge channel by a thread.

7. The gas well downhole jet-enhanced multi-stage gas-liquid high-efficiency separation device according to claim 6, characterized in that: The lower end of the upper outer pipe is connected to the bridge channel by a thread, and the lower end of the pump outer pipe is connected to the inner wall of the bridge channel outlet pipe by a thread.

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