Gas well underground liquid-carrying enhanced gas-liquid separation device and separation method thereof

Abstract

The invention relates to a gas well underground liquid carrying enhanced gas-liquid separation device and a separation method thereof, and the gas well underground liquid carrying enhanced gas-liquid separation device comprises an accumulated liquid removing and liquid carrying enhanced structure and a gas-liquid separation structure, the accumulated liquid removing and carrying enhancing structure comprises a lower outer sleeve, a flow control pier, a flow control ball, a liquid accumulation cavity, a flow controller, a variable pitch type small spiral flow channel and a bridge type channel. The gas-liquid separation structure comprises an upper outer sleeve, a spiral flow channel, a conical spiral flow channel shell, a gravity turn-back device, a settling cavity and a screw pump; the accumulated liquid removing and carrying enhancement structure utilizes a flow control pier and a flow control ball to change the accumulated liquid into small liquid drops, and the small liquid drops and mixed liquid enter together and are separated; the gas-liquid separation structure carries out cyclone separation and gravity and coupling separation on gas and liquid by utilizing a spiral flow channel and a gravity turn-back area, the gravity turn-back area prevents the gas from flowing downwards along with the liquid, and the gas phase and the liquid phase which are not separated are separated and reinjected to the ground; according to the gas-liquid two-phase separator, gas-liquid two-phase separation can be completed under the condition of occupying a small space.

Description

Technical Field

[0001] This invention relates to a separation device used in the field of gas-liquid separation in high-gas-content downhole wells, specifically a device capable of achieving efficient separation of liquid and gas phase media in a confined downhole space. Background Technology

[0002] In the later stages of production in high-gas-content wells, due to decreased formation pressure or reduced production capacity, the wellbore temperature gradient increases, causing water vapor in the natural gas to condense into liquid water. When the gas production is insufficient to carry this condensate, the liquid accumulates at the bottom of the well. Liquid accumulation increases back pressure, limiting well production capacity. Typical symptoms include fluctuating gas production, decreased wellhead temperature, and increased pressure difference between the oil well and casing. Severe liquid accumulation can also cause abnormal wellbore pressure gradients, resulting in low separation efficiency.

[0003] To address the problem of low gas-liquid separation efficiency, engineers have proposed several solutions. Solution 1, as shown in Chinese patent document CN105370261A, utilizes blades on a screw rod for gas-liquid separation. The gas-liquid mixture flows through the screw rod inside the cylinder to the separation connector, 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. It cannot perform further gas-liquid separation on the separated gas phase, and the accumulated liquid generated during operation cannot be removed. The presence of accumulated liquid affects the gas-liquid separation efficiency, thus the gas-liquid separation efficiency is not high.

[0004] Option 2, as shown in Chinese Utility Model Patent ZL201621062438.3, involves a gas that is no longer in contact with the produced mixture after gas-liquid separation, 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] One object of the present invention is to provide a gas-liquid separation device with enhanced liquid carrying capacity in a gas well, which solves the problem of low separation efficiency of existing gas-liquid separation devices in the confined space of a high gas-content well.

[0006] The technical solution adopted by this invention to solve its technical problem is as follows: This gas well downhole liquid-carrying enhanced gas-liquid separation device consists of a liquid-carrying enhancement structure with a gas-liquid separation structure at the upper end. The liquid-carrying enhancement structure includes a lower outer sleeve, a flow control block, a flow control ball, a liquid accumulation chamber, a throttle, and a bridge-type channel. The liquid accumulation chamber is coaxially arranged inside the lower outer sleeve. An inner cone is formed downward on the inner wall of the lower end of the liquid accumulation chamber. A spring fixing tube is arranged on the outer wall of the inner cone. Several small holes for the liquid accumulation chamber are distributed at the lower end of the liquid accumulation chamber. The flow control block is fixed at the lower port of the liquid accumulation chamber. The upper port of the flow control block tube is stuck at the cone opening of the inner cone. The flow control ball naturally falls on the upper port of the flow control block tube. A spring is fixed in place, with the upper end of each spring wound around the corresponding spring fixing tube. The flow control tube is provided with a square groove. Several liquid inlet holes are provided at the upper end of the liquid accumulation chamber. The upper port of the liquid accumulation chamber and the upper port of the lower outer sleeve are connected to a throttle. The throttle is provided with multiple throttle through holes. A variable pitch small spiral flow channel is welded in each throttle through hole. The upper end of the throttle is connected to a bridge channel. The upper end of the bridge channel is connected to a gas-liquid separation structure. The gas-liquid separation structure includes an upper outer sleeve. From bottom to top, a screw pump, a settling chamber, a gravity deflector, and a conical spiral flow channel shell are arranged in the upper outer sleeve. The spiral flow channel is installed at the upper end of the conical spiral flow channel shell.

[0007] In the above scheme, the gravity deflector is threaded into the gravity deflector housing. The lower end of the gravity deflector housing is also connected to the upper end of the settling chamber via an external thread. The gravity deflector is composed of a cylinder fixed on a threaded base. The threaded base is evenly distributed with gravity deflector outlets, which are located outside the cylinder. The conical spiral flow channel housing is integrally composed of an upper cylinder section, a conical section, and a lower pipe section. The junction of the conical section and the lower pipe section has an outer ring plate. The upper end of the upper cylinder section has an inlet, and the lower end of the lower pipe section has a flow outlet. The spiral flow channel is located inside the upper cylinder section, the conical section is located at the upper part of the gravity deflector housing, and the lower pipe section is inserted into the bottom of the cylinder of the gravity deflector. The outer ring plate divides the gravity deflector housing into two sections.

[0008] In the above scheme, the lower end of the lower outer sleeve is threaded to the upper end of the lower oil pipe coupling, and the upper end of the lower outer sleeve is threaded to the outer side of the lower end of the throttle; the inner side of the lower end of the throttle is threaded to the upper end of the liquid accumulation chamber; there are a total of 6 variable pitch small spiral flow channels; the upper end of the throttle is threaded to the lower end of the bridge channel; and the lower end of the liquid accumulation chamber is threaded to the base of the flow control pier.

[0009] In the above scheme, the flow control block is symmetrically provided with protrusions, and the lower port of the liquid accumulation chamber is symmetrically provided with protrusion grooves. The flow control block is fixed at the lower port of the liquid accumulation chamber by the protrusions being locked onto the protrusion grooves; the spring is locked onto the corresponding spring fixing tube and can move up and down.

[0010] In the above scheme, the lower end of the upper outer sleeve is threadedly connected to the upper end of the bridge channel; the upper end of the spiral flow channel is threadedly connected to the upper oil pipe coupling; the upper port of the spiral flow channel has a protruding jacket below the external thread, the jacket is threaded, and the jacket is threadedly connected to the outer shell of the conical spiral flow channel; the upper cylindrical section of the conical spiral flow channel outer shell has an external thread at the junction with the conical section, and the outer shell of the conical spiral flow channel is threadedly connected to the upper end of the gravity deflector shell through this external thread; the lower end of the gravity deflector shell is threadedly connected to the lower end of the gravity deflector through an internal thread, and the lower end of the gravity deflector shell is threadedly connected to the upper end of the settling chamber through an external thread, and the lower end of the settling chamber is threadedly connected to the upper end of the screw pump.

[0011] In the above scheme, the bridge channel is a cylinder with a closed lower port and an open upper port. The inlet of the bridge channel is an axial through hole evenly distributed on the cylinder wall, and the outlet of the bridge channel is a plurality of radial through holes on the cylinder wall that communicate with the inner cavity of the cylinder.

[0012] The method for gas-liquid separation using the above-mentioned downhole liquid-carrying enhanced gas-liquid separator: The accumulated fluid generated in the well is stored in the fluid accumulation chamber. When the well is shut in, due to gravity, the flow control ball presses the flow control block to its lowest point. The flow control ball is precisely stuck at the conical opening of the cone inside the fluid accumulation chamber, preventing the fluid from flowing down and causing it to accumulate in the upper part of the fluid accumulation chamber. When the well is opened, due to the bottom hole pressure, gas is generated and sprayed onto the flow control block, pushing the flow control block upwards. The flow control ball is then pushed open, and the accumulated fluid enters the flow control block pipe and flows into the lower part of the fluid accumulation chamber from the square groove. After passing through the small hole in the lower part of the fluid accumulation chamber, the liquid phase becomes small droplets and, together with the mixed liquid entering from the lower port of the fluid accumulation chamber, rises along the annulus between the fluid accumulation chamber and the lower outer sleeve. It then enters the fluid accumulation chamber through the fluid inlet hole, and then enters the bridge-type channel mixed liquid inlet through the throttle device, entering the gas-liquid separation structure. The variable pitch small spiral flow channel welded in the through hole of the throttle device can change the flow velocity, increasing the gas phase transport speed and strengthening the liquid carrying capacity. The mixed liquid from the bridge-type channel inlet enters the gas-liquid separator through the inlet at the upper end of the conical spiral flow channel shell. The mixed liquid first passes through the spiral flow channel for gas-liquid cyclone separation, and then passes through the gravity deflector for gravity coupling separation. Due to the large density difference between the gas and liquid, the liquid phase, under the impact of the upper part of the gravity deflector, enters the gravity deflection zone through the lower outlet of the conical spiral flow channel shell. The gas phase is blocked and discharged upward through the upper oil pipe coupling. The liquid phase entering the gravity deflection zone finally flows from the gravity deflector outlet to the settling chamber. Finally, it is pumped into the bridge-type channel by the suction of the screw pump and reinjected into the ground from the liquid phase outlet of the bridge-type channel. Beneficial effects

[0013] 1. In addition to the liquid carrying capacity enhancement structure, the present invention utilizes an innovative structure to transform the accumulated liquid into small droplets for easy gas phase carrying. The liquid droplets are then mixed with the mixed liquid and enter the separation structure together for gas-liquid two-phase separation, which improves the gas phase liquid carrying capacity and can solve the problem of low separation efficiency caused by liquid accumulation.

[0014] 2. This invention innovatively proposes a throttle structure, in which a variable pitch small spiral flow channel welded inside the throttle's through hole can change the flow rate and increase the gas transport speed, making the gas carry-liquid capacity stronger, and improving separation efficiency while throttling.

[0015] 3. The gas-liquid separation structure proposed in this invention utilizes its unique structure to achieve two-stage separation of the gas and liquid phases. First, the mixture is separated by swirling flow through a spiral channel, and then by gravity coupling separation through a gravity reversal zone. The gravity reversal zone utilizes the density difference between the gas and liquid phases; the liquid flows to both sides under impact, while the gas is blocked and follows the liquid flow, thus achieving secondary separation of the gas and liquid phases and greatly improving separation efficiency.

[0016] 4. This invention can be installed in the confined space of a wellbore, achieving efficient separation and collecting the liquid phase while discharging the gas phase. The liquid-carrying enhancement structure involved solves the problem of low separation efficiency caused by accumulated liquid during the separation process, improving the liquid-carrying capacity of the gas phase and thus increasing separation efficiency. The throttle design utilizes a variable-pitch small spiral flow channel to gradually increase the gas phase transport velocity, improving the liquid-carrying capacity of the gas phase. This not only improves gas-liquid separation efficiency but also enhances the practicality of the equipment. It is a high-gas-content downhole two-phase high-efficiency separation device that can achieve efficient separation of gas and liquid phases within a limited space, improving the economics of gas well exploitation.

[0017] 5. The high-pressure downhole swirling two-phase medium high-efficiency separation device provided by this invention utilizes gravity and gas self-flow. It innovatively designs a liquid-carrying enhancement structure to transform the liquid generated during separator operation into small droplets that are easily carried by the gas phase, thereby improving the liquid-carrying capacity. The throttle uses a variable-pitch small spiral flow channel design to gradually enhance the gas phase transport speed, thereby improving the gas phase liquid-carrying capacity. At the same time, the arrangement of the gravity deflector can realize gas-liquid re-separation, achieving two-stage separation and greatly improving the separation efficiency.

[0018] 6. This invention removes accumulated liquid and improves liquid carrying capacity while enabling the separation of gas-liquid two-phase media in a small space. After separation, the gas phase is discharged to the external space of the equipment, which improves the service life of other operating equipment. At the same time, it completes the pre-separation of produced liquid, which indirectly improves the gas well recovery rate and reduces the energy consumption of the subsequent separation system. Attached Figure Description

[0019] Figure 1The diagram is a schematic diagram of the present invention, wherein (a) is an overall appearance view of the present invention, and (b) is a cross-sectional view of the present invention.

[0020] Figure 2 This is a schematic diagram of the liquid-carrying reinforcement structure, where (a) is an external view of the liquid-carrying reinforcement structure. Figure 2 (b) is a cross-sectional view of the liquid-carrying reinforcement structure.

[0021] Figure 3 Exploded view of the structure to remove accumulated liquid and enhance its structure.

[0022] Figure 4 The diagram shows a bridge passage, where (a) is an exterior view of the bridge passage and (b) is a cross-sectional view of the bridge passage.

[0023] Figure 5 The diagram shows a flow regulator, where (a) is an external view of the flow regulator and (b) is a cross-sectional view of the flow regulator.

[0024] Figure 6 The diagram shows a variable pitch small spiral flow channel, where (a) is an external view of the variable pitch small spiral flow channel and (b) is a cross-sectional view of the variable pitch small spiral flow channel.

[0025] Figure 7 The diagram shows the effusion cavity, where (a) is the external view of the effusion cavity and (b) is the cross-sectional view of the effusion cavity.

[0026] Figure 8 The diagram shows the flow control pier, where (a) is an external view of the flow control pier and (b) is a sectional view of the flow control pier. (c) shows the state of the flow control block and flow control ball when the well is closed, and (d) shows the state of the flow control block and flow control ball when the well is opened.

[0027] Figure 9 A schematic diagram of a gas-liquid separation structure, where (a) is an external view of the gas-liquid separation structure and (b) is a cross-sectional view of the gas-liquid separation structure.

[0028] Figure 10 This is an exploded view of a gas-liquid separation structure.

[0029] Figure 11 The diagram shows a gravity turnaround device, where (a) is an external view of the gravity turnaround device and (b) is a cross-sectional view of the gravity turnaround device.

[0030] In the figure: 1-Liquid carrying enhancement structure, 101-Lower oil pipe coupling, 102-Lower outer sleeve, 103-Flow control pier base, 104-Flow control pier, 1041-Protrusion, 1042-Square groove, 1043-Spring, 105-Flow control ball, 106-Liquid accumulation chamber, 1061-Liquid accumulation chamber inlet, 1062-Liquid accumulation chamber small hole, 1063-Conical opening, 1064-Protrusion groove, 1065-Spring fixing tube, 107-Throttle, 1071-Throttle through hole, 108-Variable pitch small spiral flow channel, 109-Bridge channel, 1091-Bridge channel liquid phase outlet, 1092-Bridge channel mixed liquid inlet; 2. Gas-liquid separation structure, 201-upper outer sleeve, 202-upper oil pipe coupling, 203-spiral flow channel, 204-conical spiral flow channel shell, 2041-liquid inlet, 2042-lower liquid outlet, 205-gravity deflector shell, 206-gravity deflector, 2061-gravity deflector outlet, 207-settling chamber, 208-screw pump. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings: See Figures 1-11 This downhole liquid-carrying enhanced gas-liquid separation device for gas wells consists of a liquid-carrying enhancement structure 1 with a gas-liquid separation structure 2 at its upper end. The liquid-carrying enhancement structure 1 includes a lower outer sleeve 102, a flow control pier 104, a flow control ball 105, a liquid accumulation chamber 106, a flow throttle 107, and a bridge-type channel 109. The liquid accumulation chamber 106 is coaxially arranged inside the lower outer sleeve 102. The inner wall of the lower end of the liquid accumulation chamber 106 forms an inner cone facing downwards, and a spring fixing tube is installed on the outer wall of the inner cone. Several small holes for the liquid accumulation chamber are distributed at the lower end of the liquid accumulation chamber 106. The flow control pier 104 is fixed at the lower port of the liquid accumulation chamber 106 to control the flow. The upper end of the pier tube is stuck at the cone opening of the inner cone, and the flow control ball 105 naturally falls on the upper end of the flow control pier tube. The flow control pier 104 is fixed with a spring, and the upper end of each spring is wrapped around the corresponding spring fixing tube. The flow control pier tube is provided with a square groove. The upper end of the liquid accumulation chamber 106 is provided with several liquid accumulation chamber inlet holes. The upper end of the liquid accumulation chamber and the upper end of the lower outer sleeve are connected to the throttle 107. The throttle 107 is provided with multiple throttle through holes. A variable pitch small spiral flow channel 108 is welded in each throttle through hole. The upper end of the throttle 107 is connected to the bridge channel, and the upper end of the bridge channel is connected to the gas-liquid separation structure.

[0032] The lower end of the lower oil pipe coupling 101 is threaded to the upper end of the lower outer sleeve 102; the upper end of the lower outer sleeve 102 is threaded to the outer side of the lower end of the throttle 107; the inner side of the lower end of the throttle 107 is threaded to the upper end of the liquid accumulation chamber 106; six variable pitch small spiral flow channels 108 are welded into the through hole 1071 of the throttle; the upper end of the throttle 107 is threaded to the lower end of the bridge channel 109; the lower end of the liquid accumulation chamber 106 is threaded to the structure and the flow control pier base 103. The flow control block 104 is provided with protrusions 1041 and springs 1043 on both sides. The liquid accumulation chamber 106 is provided with protrusion grooves 1064 and spring fixing tubes 1065. The protrusions 1041 are stuck on the protrusion grooves 1064 and the springs 1043 are stuck on the spring fixing tubes 1065, and can move up and down.

[0033] During operation, liquid and gas inevitably accumulate. This liquid is stored in the liquid accumulation chamber 106. When shutting in the well, gravity forces the flow control ball 105 to press the flow control block 104 to its lowest point. The flow control ball 105 is precisely stuck in the conical opening 1063 of the liquid accumulation chamber, preventing the liquid from flowing down and causing it to accumulate on the upper part of the liquid accumulation chamber 106. When opening the well, due to the bottom hole pressure, gas is generated and ejected onto the flow control block 104, pushing it upwards. The flow control ball 105 is also pushed open, and the accumulated liquid enters the flow control block pipe from the square groove. 1042 flows into the lower part of the liquid accumulation chamber 106. The liquid phase is transformed into small droplets through the small hole 1062 on the side wall of the lower part of the liquid accumulation chamber 106. It flows upward together with the mixed liquid entering from below, enters the liquid accumulation chamber 106 through the liquid inlet hole 1061, and enters the bridge channel mixed liquid inlet 1092 through the throttle 107, and enters the gas-liquid separation structure. The variable pitch small spiral flow channel 108 welded in the through hole 1071 of the throttle can change the flow rate, increase the gas phase transport speed, and enhance the liquid carrying capacity.

[0034] The gas-liquid separation structure includes an upper outer sleeve 201. Inside the upper outer sleeve 201, from bottom to top, are arranged a screw pump 208, a settling chamber 207, a gravity deflector 206, and a conical spiral flow channel shell 204. The spiral flow channel is installed at the upper end of the conical spiral flow channel shell. The gravity deflector 206 is threaded into the gravity deflector housing. The lower end of the gravity deflector housing is also connected to the upper end of the settling chamber via an external thread. The gravity deflector 206 is composed of a cylindrical body fixed on a threaded base. The threaded base is evenly distributed with gravity deflector outlets, which are located outside the cylinder. The conical spiral flow channel housing 204 is integrally composed of an upper cylinder section, a conical section, and a lower pipe section. The junction of the conical section and the lower pipe section has an outer ring plate. The upper end of the upper cylinder section has an inlet, and the lower end of the lower pipe section has a flow outlet. The spiral flow channel is located inside the upper cylinder section, the conical section is located at the upper part of the gravity deflector housing, and the lower pipe section is inserted into the bottom of the cylinder of the gravity deflector. The outer ring plate divides the gravity deflector housing into two sections.

[0035] The lower end of the upper outer sleeve 201 is threaded to the upper end of the bridge channel 109; the lower end of the upper oil pipe coupling 202 is threaded to the upper end of the spiral flow channel 203; the two protruding parts on both sides of the upper end of the spiral flow channel 203 are threaded to the conical spiral flow channel outer shell 204; the maximum diameter of the conical spiral flow channel outer shell 204 is threaded to the upper end of the gravity deflector outer shell 205; the inner and outer sides of the lower end of the gravity deflector outer shell 205 are threaded to the upper ends of the gravity deflector 206 and the settling chamber 207, respectively; the lower end of the settling chamber 207 is threaded to the upper end of the screw pump 208. After the liquid accumulation structure is removed and the liquid is mixed with the mixture, it enters the separator through the inlet 2041. The mixture first passes through the spiral channel 203 for gas-liquid cyclone separation, and then passes through the gravity deflector 206 for gravity coupling separation. Due to the large density difference between the gas and the liquid, the liquid phase, under the impact of the upper part of the gravity deflector, flows to both sides through the lower liquid outlet 2042 on the conical spiral channel shell 204 and enters the gravity deflection zone. The gas phase is blocked and discharged upward through the upper oil pipe coupling 202. The liquid phase that enters the gravity deflection zone finally flows from the gravity deflector outlet 2061 on the gravity deflector 206 to the settling chamber 207. Finally, it is pumped to the bridge channel 109 by the suction of the screw pump 208 and reinjected into the ground from the liquid phase outlet 1091 of the bridge channel.

[0036] The present invention is more specifically as follows: The liquid-carrying enhancement structure 1 includes a lower oil pipe coupling 101, a lower outer sleeve 102, a flow control base 103, a flow control block 104, a flow control ball 105, a liquid accumulation chamber 106, a throttle 107, a variable pitch small spiral flow channel 108, and a bridge-type channel 109. The lower end of the lower oil pipe coupling 101 is threadedly connected to the upper end of the lower outer sleeve 102; the upper end of the lower outer sleeve 102 is threadedly connected to the outer side of the lower end of the throttle 107; the inner side of the lower end of the throttle 107 is threadedly connected to the upper end of the liquid accumulation chamber 106; the variable pitch... Six small spiral channels 108 are welded into the through holes 1071 of the throttle; the upper end of the throttle 107 is connected to the lower end of the bridge channel 109 by a thread; the lower end of the liquid accumulation chamber 106 is connected to the structure and the base 103 of the flow control pier by a thread; the flow control pier 104 is provided with protrusions 1041 and springs 1043 on both sides; the liquid accumulation chamber 106 is provided with protrusion grooves 1064 and spring fixing tubes 1065; the protrusions 1041 are stuck in the protrusion grooves 1064 and the springs 1064 are stuck in the spring fixing tubes 1065, and can move up and down. During operation, liquid and gas inevitably accumulate. This liquid is stored in the liquid accumulation chamber 106. When shutting in the well, gravity causes the flow control ball 105 to press the flow control block 104 to its lowest point. The flow control ball 105 is stuck in the cone opening 1063 of the cone inside the liquid accumulation chamber, preventing the liquid from flowing down and causing it to accumulate in the upper part of the liquid accumulation chamber 106. When opening the well, due to the bottom hole pressure, gas is generated and sprayed onto the flow control block 104, pushing it upward. The flow control ball 105 is also pushed open, and the liquid enters the flow control block pipe and flows from the square groove 1042 into the lower part of the liquid accumulation chamber 106. The liquid phase passes through the small hole 1062 on the side wall of the lower part of the liquid accumulation chamber 106 and becomes small droplets. It flows upward together with the mixed liquid entering from below and enters the liquid accumulation chamber 106 through the liquid inlet hole 1061. After passing through the throttle 107, it enters the bridge channel mixed liquid inlet 1092 and enters the gas-liquid separation structure.

[0037] The gas-liquid separation structure 2 includes an upper outer sleeve 201, an upper oil pipe coupling 202, a spiral flow channel 203, a conical spiral flow channel outer shell 204, a gravity deflector outer shell 205, a gravity deflector 206, a settling chamber 207, and a screw pump 208. The lower end of the upper outer sleeve 201 is threadedly connected to the upper end of the bridge-type channel 109. The lower end of the upper oil pipe coupling 202 is threadedly connected to the upper end of the spiral flow channel 203. The upper ends of the spiral flow channel 203 protrude on both sides and are threadedly connected to the conical spiral flow channel outer shell 204. The point of maximum cone diameter of the conical spiral flow channel outer shell 204 is threadedly connected to the upper end of the gravity deflector outer shell 205. The inner and outer sides of the lower end of the gravity deflector outer shell 205 are threadedly connected to the upper ends of the gravity deflector 206 and the settling chamber 207, respectively. The lower end of the settling chamber 207 is threadedly connected to the upper end of the screw pump 208. The end is connected by a thread; after the liquid is removed and the small droplets are mixed with the liquid, they enter the separator through the inlet 2041. The liquid first passes through the spiral channel 203 for gas-liquid cyclone separation, and then passes through the gravity deflector 206 for gravity coupling separation. Due to the large density difference between the gas and the liquid, the liquid phase is impacted by the upper part of the gravity deflector and flows to both sides through the lower liquid outlet 2042 on the conical spiral channel shell 204 into the gravity deflection zone. The gas phase is blocked and discharged upward through the upper oil pipe coupling 202. The liquid phase that enters the gravity deflection zone finally flows from the gravity deflector outlet 2061 on the gravity deflector 206 to the settling chamber 207. Finally, it is pumped to the bridge channel 109 by the suction of the screw pump 208 and reinjected into the ground from the liquid phase outlet 1091. like Figure 1As shown, the present invention is placed vertically inside the downhole pipeline, ensuring that the downhole tubing coupling is located at the bottommost end, and each part is connected upwards in sequence according to the corresponding connection method. During operation, liquid and gas inevitably accumulate. This liquid is stored in the liquid accumulation chamber 106. When shutting in the well, gravity forces the flow control ball 105 to press the flow control block 104 to its lowest point. The flow control ball 105 is precisely stuck in the conical opening 1063 of the liquid accumulation chamber, preventing the liquid from flowing down and causing it to accumulate in the upper part of the liquid accumulation chamber 106. When opening the well, due to the bottom hole pressure, gas is generated and ejected onto the flow control block 104, pushing it upwards. The flow control ball 105 is also pushed open, and the liquid enters the flow control block pipe and flows from the square groove 1042 into the lower part of the liquid accumulation chamber 106. The liquid phase passes through the small holes 1062 on the side wall of the lower part of the liquid accumulation chamber 106, turning into small droplets. These droplets flow upwards together with the mixed liquid entering from below, entering the liquid accumulation chamber 106 through the liquid inlet hole 1061, and then through the throttle 107 into the bridge-type channel mixed liquid inlet 10. 92. Entering the gas-liquid separation structure, the liquid enters the separator through the inlet 2041. The mixture first passes through the spiral channel 203 for gas-liquid cyclone separation, and then through the gravity deflector 206 for gravity coupling separation. Due to the large density difference between the gas and liquid, the liquid phase, under the impact of the upper part of the gravity deflector, flows to both sides through the lower outlet 2042 on the conical spiral channel shell 204 into the gravity deflection zone. The gas phase is blocked and discharged upwards through the upper oil pipe coupling 202. The liquid phase entering the gravity deflection zone finally flows from the gravity deflector outlet 2061 on the gravity deflector 206 to the settling chamber 207, and is finally pumped to the bridge channel 109 by the suction of the screw pump 208, and reinjected into the ground from the liquid phase outlet 1091. The appearance and cross-sectional view of the liquid-carrying enhancement structure are as follows. Figure 2 As shown, the flow control pier 104 and flow control ball 105 are in the following states when the well is shut in: Figure 8 As shown in (c), the flow control ball 105 is plugged at the cone opening 1063 of the fluid accumulation chamber, and the fluid is stored in the upper part of the fluid accumulation chamber. The state of the flow control block 104 and the flow control ball 105 during well opening is as follows. Figure 8 As shown in (d), due to the bottom hole pressure, gas spontaneously sprays onto the bottom of the flow control pier 104. The spraying force pushes it upward, and the flow control ball 105 is also pushed open. The accumulated liquid enters the flow control pier pipe and flows from the square groove 1042 into the lower part of the liquid accumulation chamber 106. The liquid phase passes through the small holes 1062 on the side wall of the lower part of the liquid accumulation chamber 106 and becomes small droplets. It flows upward together with the mixed liquid entering from below, enters the liquid accumulation chamber 106 through the liquid inlet hole 1061, and enters the bridge-type channel mixed liquid inlet 1092 through the throttle device 107, entering the gas-liquid separation structure; the exploded view of the liquid carrying enhancement structure is shown below. Figure 3 As shown; the exterior view and sectional view of the bridge-type channel are as follows. Figure 4 As shown, the liquid mixture with accumulated liquid flows into the gas-liquid separation module through the bridge-type channel liquid inlet 1092, and the separated liquid phase flows out from the bridge-type channel liquid phase outlet 1091; the external and sectional views of the throttle are shown below. Figure 5As shown, the external view and cross-sectional view of the variable pitch small spiral flow channel are as follows. Figure 6 As shown, the variable pitch small spiral flow channel 108 is welded inside the throttle hole 1071. This design can change the flow rate, making the gas phase transport velocity greater and the liquid carrying capacity stronger; the external view and cross-sectional view of the liquid accumulation chamber are shown below. Figure 7 As shown, the liquid phase passes through the small hole 1062 on the lower sidewall of the accumulating chamber 106, turning into small droplets. These droplets flow upwards along with the mixed liquid entering from below, and then enter the accumulating chamber 106 through the inlet hole 1061. The accumulating chamber protrusion groove 1064 is used for the installation and vertical movement of the flow control pier. When the well is shut in, the flow control ball falls into the conical opening 1063 within the accumulating chamber. The external and sectional views of the flow control pier are shown below. Figure 8 As shown, the protrusion 1041 is engaged in the protrusion groove of the liquid accumulation chamber, allowing it to move up and down. The spring 1043 is used to assist in the movement. During well opening, the accumulated liquid flows out from the square groove 1042 of the flow control block. The appearance and cross-sectional view of the gas-liquid separation structure are shown below. Figure 9 As shown, the mixture enters the separator through inlet 2041. It first passes through spiral channel 203 for gas-liquid cyclone separation, then through gravity deflector 206 for gravity-coupled separation. Due to the large density difference between the gas and liquid, the liquid phase, impacted by the upper part of the gravity deflector, flows to both sides through the lower outlet 2042 on the conical spiral channel shell 204 into the gravity deflection zone. The gas phase is blocked and discharged upwards through the upper oil pipe coupling 202. The liquid phase entering the gravity deflection zone finally flows from gravity deflector outlet 2061 on gravity deflector 206 to settling chamber 207, and finally is pumped to bridge channel 109 by screw pump 208, and reinjected into the ground from liquid outlet 1091. An exploded view of the gas-liquid separation structure is shown below. Figure 10 As shown; the external view and sectional view of the gravity deflector are as follows. Figure 11 As shown, the separated liquid phase flows from the gravity deflector outlet 2061 into the settling chamber.

[0038] This invention features a simple overall structure. The liquid-carrying enhancement structure transforms the unavoidable liquid buildup during separator operation into small droplets, which then enter the separator along with the mixed liquid for separation. This effectively solves the problem of low gas-liquid separation efficiency caused by liquid buildup, enhancing gas-liquid carrying capacity and improving separation efficiency. The throttle section utilizes a variable-pitch small spiral flow channel to gradually increase the gas phase transport velocity, improving the gas-liquid carrying capacity. The gas-liquid separation structure employs swirling flow coupled with gravity to perform two-stage gas-liquid separation, significantly improving separation efficiency. It can achieve highly efficient separation of gas-liquid two-phase media in confined downhole spaces and has a wide range of applications.

Claims

1. A downhole liquid-carrying enhanced gas-liquid separation device for a gas well, characterized by: This downhole liquid-carrying enhanced gas-liquid separation device for gas wells consists of a liquid-carrying enhancement structure with a gas-liquid separation structure at the upper end. The liquid-carrying enhancement structure includes a lower outer sleeve, a flow control pier, a flow control ball, a liquid accumulation chamber, a throttle, and a bridge-type channel. The liquid accumulation chamber is coaxially arranged inside the lower outer sleeve. An inner cone is formed downwards on the lower inner wall of the liquid accumulation chamber, and a spring-fixed tube is installed on the outer wall of the inner cone. Several small holes are distributed at the lower end of the liquid accumulation chamber. The flow control pier is fixed at the lower port of the liquid accumulation chamber, and the upper port of the flow control pier tube is engaged with the cone opening of the inner cone. The flow control ball naturally falls onto the upper port of the flow control pier tube. Springs are fixed to the flow control pier, and each spring... All ends are wound around the corresponding spring fixing tube. The flow control tube is provided with a square groove. The upper end of the liquid accumulation chamber is provided with several liquid accumulation chamber inlet holes. The upper port of the liquid accumulation chamber and the upper port of the lower outer sleeve are connected to the throttle. The throttle is provided with multiple throttle through holes. A variable pitch small spiral flow channel is welded in each throttle through hole. The upper end of the throttle is connected to the bridge channel. The upper end of the bridge channel is connected to the gas-liquid separation structure. The gas-liquid separation structure includes an upper outer sleeve. The upper outer sleeve is provided with a screw pump, a settling chamber, a gravity deflector, and a conical spiral flow channel shell from bottom to top. The spiral flow channel is installed on the upper end of the conical spiral flow channel shell.

2. The gas well downhole liquid-carrying enhanced gas-liquid separation device according to claim 1, characterized in that: The gravity deflector is threaded into the gravity deflector housing. The lower end of the gravity deflector housing is also connected to the upper end of the settling chamber via an external thread. The gravity deflector is composed of a cylindrical body fixed on a threaded base. The threaded base is evenly distributed with gravity deflector outlets, which are located outside the cylindrical body. The conical spiral flow channel housing is integrally composed of an upper cylindrical section, a conical section, and a lower pipe section. The junction of the conical section and the lower pipe section has an outer ring plate. The upper end of the upper cylindrical section has an inlet, and the lower end of the lower pipe section has a flow outlet. The spiral flow channel is located inside the upper cylindrical section, the conical section is located at the upper part of the gravity deflector housing, and the lower pipe section is inserted into the bottom of the cylindrical body of the gravity deflector. The outer ring plate divides the gravity deflector housing into two sections.

3. The gas well downhole liquid-carrying enhanced gas-liquid separation device according to claim 2, characterized in that: The lower end of the lower outer sleeve is threaded to the upper end of the lower oil pipe coupling, and the upper end of the lower outer sleeve is threaded to the outer side of the lower end of the throttle; the inner side of the lower end of the throttle is threaded to the upper end of the liquid accumulation chamber; there are a total of 6 variable pitch small spiral flow channels; the upper end of the throttle is threaded to the lower end of the bridge channel; and the lower end of the liquid accumulation chamber is threaded to the base of the flow control pier.

4. The gas well downhole liquid-carrying enhanced gas-liquid separation device according to claim 3, characterized in that: The flow control block is symmetrically provided with protrusions, and the lower port of the liquid accumulation chamber is symmetrically provided with protrusion grooves. The flow control block is fixed at the lower port of the liquid accumulation chamber by the protrusions being locked onto the protrusion grooves; the spring is locked onto the corresponding spring fixing tube and can move up and down.

5. The gas well downhole liquid-carrying enhanced gas-liquid separator according to claim 4, characterized in that: The lower end of the upper outer sleeve is threadedly connected to the upper end of the bridge-type channel; the upper end of the spiral flow channel is threadedly connected to the upper oil pipe coupling, and the upper port of the spiral flow channel has a protruding jacket below the external thread. The jacket is threaded and is threadedly connected to the outer shell of the conical spiral flow channel; the upper cylindrical section of the conical spiral flow channel outer shell has an external thread at the junction with the conical section, and the outer shell of the conical spiral flow channel is threadedly connected to the upper end of the gravity deflector shell through this external thread; the lower end of the gravity deflector shell is threadedly connected to the lower end of the gravity deflector through an internal thread, and the lower end of the gravity deflector shell is threadedly connected to the upper end of the settling chamber through an external thread. The lower end of the settling chamber is threadedly connected to the upper end of the screw pump.

6. The gas well downhole liquid-carrying enhanced gas-liquid separation device according to claim 5, characterized in that, The bridge-type channel is a cylindrical body with a closed lower port and an open upper port. The inlet of the bridge-type channel is an axial through hole evenly distributed on the cylinder wall, and the outlet of the bridge-type channel is a plurality of radial through holes on the cylinder wall that communicate with the inner cavity of the cylinder.

7. A separation method for a gas-liquid separation device with downhole liquid carrying enhancement as described in claim 6, characterized in that: The accumulated fluid generated in the well is stored in the fluid accumulation chamber. When the well is shut in, due to gravity, the flow control ball presses the flow control block to its lowest point. The flow control ball is precisely stuck at the conical opening of the cone inside the fluid accumulation chamber, preventing the fluid from flowing down and causing it to accumulate in the upper part of the fluid accumulation chamber. When the well is opened, due to the bottom hole pressure, gas is generated and sprayed onto the flow control block, pushing the flow control block upwards. The flow control ball is then pushed open, and the accumulated fluid enters the flow control block pipe and flows into the lower part of the fluid accumulation chamber from the square groove. After passing through the small hole in the lower part of the fluid accumulation chamber, the liquid phase becomes small droplets and, together with the mixed liquid entering from the lower port of the fluid accumulation chamber, rises along the annulus between the fluid accumulation chamber and the lower outer sleeve. It then enters the fluid accumulation chamber through the fluid inlet hole, and then enters the bridge-type channel mixed liquid inlet through the throttle device, entering the gas-liquid separation structure. The variable pitch small spiral flow channel welded in the through hole of the throttle device can change the flow velocity, increasing the gas phase transport speed and strengthening the liquid carrying capacity. The mixed liquid from the bridge-type channel inlet enters the gas-liquid separator through the inlet at the upper end of the conical spiral flow channel shell. The mixed liquid first passes through the spiral flow channel for gas-liquid cyclone separation, and then passes through the gravity deflector for gravity coupling separation. Due to the large density difference between the gas and liquid, the liquid phase, under the impact of the upper part of the gravity deflector, enters the gravity deflection zone through the lower outlet of the conical spiral flow channel shell. The gas phase is blocked and discharged upward through the upper oil pipe coupling. The liquid phase entering the gravity deflection zone finally flows from the gravity deflector outlet to the settling chamber. Finally, it is pumped into the bridge-type channel by the suction of the screw pump and reinjected into the ground from the liquid phase outlet of the bridge-type channel.

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