High-gas-content well underground dynamic gas-liquid separation device for injection and production in same well

Abstract

The invention relates to a same-well injection-production high-gas-content well underground dynamic gas-liquid separation device which comprises a center shaft, a gas phase outlet cover, a multi-stage disc, a mixed liquid inlet device and a spiral groove-shaped outer sleeve, the upper end of the spiral groove-shaped outer sleeve is connected with the gas phase outlet cover, a spiral groove is formed in the inner wall of the spiral groove-shaped outer sleeve and extends to the cylinder bottom of the spiral groove-shaped outer sleeve, and the multi-stage disc is connected with the mixed liquid inlet device. An axial inlet is formed in the center of the cylinder bottom, a liquid phase outlet is formed in the position, close to the cylinder bottom, of the spiral groove-shaped outer sleeve, the mixed liquid inlet device is fixed to the cylinder bottom of the spiral groove-shaped outer sleeve, a central shaft hole and a mixed liquid inlet are formed in the cylinder top of the mixed liquid inlet device, and an annular gap is formed between the mixed liquid inlet device and the spiral groove-shaped outer sleeve; the gas phase outlet cover is provided with a central shaft sleeve, and a central shaft extends into the spiral groove-shaped outer sleeve and penetrates out of an axial inlet of the spiral groove-shaped outer sleeve after passing through the central shaft hole; and the multi-stage disc is arranged outside the central shaft in series and is arranged at the spiral groove above the mixed liquid inlet device. The device is good in coalescence effect, high in water trapping capacity and high in separation efficiency.

Description

Technical Field

[0001] This invention relates to a gas-liquid separation device for high gas content wells, specifically a dynamic gas-liquid separation device for high gas content wells used in both injection and production. Background Technology

[0002] With the continuous exploitation of oil fields, associated gases are gradually increasing, posing certain challenges to gas-liquid separation. Currently, gas anchor separators can efficiently separate gas and liquid phases with high gas content, but they have strict requirements on inlet velocity and are not suitable for high-flow-rate conditions. Gas-liquid hydrocyclone separation is one of the most commonly used gas-liquid separation methods. This method can rapidly separate gas and liquid phases with downhole gas content below 60%, but the separation efficiency drops significantly when the gas content exceeds 60%. Existing downhole gas-liquid separators all have certain limitations when facing complex operating conditions with high gas content and high flow rates. Therefore, developing a new type of gas-liquid separator that can adapt to high-gas-content downhole environments and possesses efficient and stable separation performance is particularly urgent and important. This innovation will not only fill the gap in existing technology but also provide strong support for the efficient and sustainable development of oil field exploitation.

[0003] Chinese utility model patent ZL201620064773.0 discloses a downhole gas-liquid separation device. This patent has few components, a simple structure, and low cost. When liquid passes through, it drives the vortex wheel to rotate, causing the liquid to generate centrifugal force and swirl against the inner wall. The liquid in the gas is concentrated in the center. Then, the liquid and gas flow out through the outer liquid discharge channel and the central gas outlet channel, respectively, to achieve gas-liquid separation. This ensures that the liquid sent to the motor is gas-free, avoiding damage to the motor and improving its service life. Summary of the Invention

[0004] The purpose of this invention is to provide a dynamic gas-liquid separation device for high gas content wells in the same well injection and production process. This dynamic gas-liquid separation device for high gas content wells in the same well injection and production process is used to solve the problems of low efficiency and incomplete separation that traditional gas-liquid separation devices often face when processing high gas content fluids.

[0005] The technical solution adopted by this invention to solve its technical problem is as follows: This dynamic gas-liquid separation device for high gas content well injection and production includes a central shaft, a gas phase outlet cover, multi-stage discs, a mixed liquid inlet, and a spiral groove-shaped outer sleeve. The upper end of the spiral groove-shaped outer sleeve is connected to the gas phase outlet cover. The inner wall of the spiral groove-shaped outer sleeve has spiral grooves, the direction of which is along the rotation direction of the mixed liquid. The spiral grooves extend to the bottom of the spiral groove-shaped outer sleeve. An axial inlet is provided at the center of the bottom of the sleeve. A liquid phase outlet is provided near the bottom of the spiral groove-shaped outer sleeve. The mixed liquid inlet is a cylinder with an open bottom and is fixed to the bottom of the spiral groove-shaped outer sleeve. A central shaft hole and a mixed liquid inlet are provided at the top of the mixed liquid inlet. There is an annular gap between the mixed liquid inlet and the spiral groove-shaped outer sleeve. The gas phase outlet cover is provided with a central shaft sleeve. The central shaft extends from the central shaft sleeve into the spiral groove-shaped outer sleeve, passes through the central shaft hole, and exits through the axial inlet of the spiral groove-shaped outer sleeve. The multi-stage discs are connected in series outside the central shaft and are driven to rotate by the central shaft. The multi-stage discs are located at the spiral groove above the mixed liquid inlet.

[0006] In the above scheme, the disc is an umbrella-shaped body with a central ring at the top. The umbrella-shaped body is radially and evenly arranged with a central hole and rectangular protrusions. The central hole and rectangular protrusions are spaced apart. The mixed liquid moves from the central hole to the next level disc. The rotation of the disc generates centrifugal force, which gathers the gas phase in the mixed liquid to the middle, and the liquid is thrown to the side wall of the disc. The rectangular protrusions block some of the gas from flowing with the liquid to the side wall of the disc.

[0007] In the above scheme, the disc has a disc keyway, the short shaft sleeve has a short shaft sleeve keyway, the central shaft has a central shaft keyway, the key is installed on the central shaft keyway, the disc is held on the key through the disc keyway, the short shaft sleeve is connected to the key through the short shaft sleeve keyway, the short shaft sleeve is held between two adjacent discs, and the disc is fixed on the central shaft.

[0008] In the above scheme, the gas phase outlet cover and the spiral groove type outer sleeve are connected by threads. The gas phase outlet cover is provided with four gas phase outlets, which are evenly arranged around the central shaft sleeve.

[0009] In the above scheme, the mixing liquid inlet is welded to the spiral groove type outer sleeve. The top of the mixing liquid inlet cylinder has four mixing liquid inlets, which are evenly arranged around the central shaft hole. The top of the mixing liquid inlet cylinder has an outer edge relative to the cylinder body. Beneficial effects

[0010] 1. This invention is applicable to dynamic gas-liquid separation devices with high gas content in downhole wells, and solves the problem of low separation efficiency of existing gas-liquid separation devices in high gas content wells.

[0011] 2. This invention innovatively designs a novel disc that utilizes the centrifugal force generated by the disc's rotation. This allows for the coalescing of gas while simultaneously capturing liquid droplets. Rectangular protrusions are added to the disc, cleverly preventing some gas from flowing with the liquid, thus significantly improving the overall separation efficiency. This optimized detail enables the device to exhibit superior separation capabilities in complex and variable downhole environments.

[0012] 3. This invention innovatively designs a shell with spiral grooves, which not only optimizes the fluid flow path but also greatly promotes the smooth downward flow of liquid along the shell's sidewalls, further enhancing the separation effect. The ingenious use of spiral grooves not only improves separation efficiency but also ensures more optimized fluid dynamics characteristics within the device, providing a strong guarantee for efficient and stable gas-liquid separation.

[0013] 4. This invention is a dynamic gas-liquid separation device specifically designed for high gas-bearing environments in both injection and production wells. It combines numerous advantages such as simple structure, stable flow field, and high separation efficiency, bringing a revolutionary breakthrough to the oilfield development field. The core of this invention lies in its innovative new disc design. The powerful centrifugal force generated during disc rotation effectively concentrates gas in the central region, while the liquid, under the precise trapping action of the disc, is thrown to the side wall and flows smoothly downwards. During this process, the carefully designed elongated main-shaped protrusions on the disc play a crucial role, cleverly blocking some of the gas from flowing with the liquid, thus significantly improving the gas-liquid separation efficiency. Furthermore, this invention also demonstrates remarkable creativity in its outer shell design. By creating spiral grooves on the outer shell, the liquid is cleverly guided downwards along the channels, further increasing the probability of liquid flowing downwards, thereby improving the separation efficiency of the liquid phase. This not only optimizes the fluid flow path but also ensures more stable and efficient fluid dynamics within the device.

[0014] 5. The dynamic gas-liquid separation device for high gas-content wells proposed in this invention successfully solves the gas-liquid separation problem in high gas-content wells thanks to its superior performance and innovative design. This device is not only suitable for high gas-content environments, but also provides strong technical support for the efficient and sustainable development of oilfields due to its high efficiency and stable separation effect.

[0015] 6. This invention is a separation device that can achieve efficient gas-liquid separation in high gas-content downhole wells. Through the rotation of multi-stage discs, the coalescence effect of the gas phase is enhanced, the water capture capacity is increased, and the separation efficiency is greatly improved. It is a gas-liquid high-efficiency separation device that can be applied to the development of high gas-content downhole oilfields in the same well injection and production process. Attached Figure Description

[0016] Figure 1This is a diagram of a dynamic gas-liquid separation device for high gas content well injection and production in the same well, where (a) is an overall appearance view and (b) is a cross-sectional view; Figure 2 An exploded view of a dynamic gas-liquid separation device for high gas content well injection and production in the same well. Figure 3 The images are of the disc, where (a) is an external view and (b) is a cross-sectional view. Figure 4 The diagram shows a spiral groove type shell, where (a) is an external view and (b) is a sectional view. Figure 5 The diagrams are short axis views, where (a) is the external view and (b) is the sectional view. Figure 6 The diagram shows the mixture inlet device, where (a) is an external view and (b) is a cross-sectional view.

[0017] In the diagram, 101-central shaft, 1011-central shaft keyway, 102-gas phase outlet cover, 1021-gas phase outlet, 103-fixed sleeve, 104-sixth stage disk, 105-fifth stage disk, 106-fourth stage disk, 107-third stage disk, 108-second stage disk, 109-first stage disk, 1041-disc center hole, 1042-rectangular protrusion, 1043-disc keyway. 110-Fifth stage short shaft sleeve, 111-Fourth stage short shaft sleeve, 112-Third stage short shaft sleeve, 113-Second stage short shaft sleeve, 114-First stage short shaft sleeve, 1101-Short shaft sleeve keyway, 115-Long shaft sleeve, 116-Mixed liquid inlet, 1161-Mixed liquid inlet, 117-Helical groove type outer sleeve, 1171-Axial inlet, 1172-Liquid phase outlet, 1173-Helical groove, 118-Key. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings: See Figures 1-6This dynamic gas-liquid separation device for high gas content well injection and production includes a central shaft 101, a gas phase outlet cover 102, multi-stage discs, a mixed liquid inlet 116, and a spiral groove-shaped outer casing 117. The upper end of the spiral groove-shaped outer casing 117 is connected to the gas phase outlet cover 102. The inner wall of the spiral groove-shaped outer casing 117 has spiral grooves 1173, which are oriented along the rotation direction of the mixed liquid and extend to the bottom of the spiral groove-shaped outer casing. An axial inlet 1171 is provided at the center of the bottom of the casing. A liquid phase outlet 1172 is provided near the bottom of the spiral groove-shaped outer casing. The mixed liquid inlet 116 is a cylindrical body with an open bottom. 116 is fixed to the bottom of the spiral groove-shaped outer casing 117. The top of the mixed liquid inlet 116 is provided with a central shaft hole and a mixed liquid inlet 1161. There is an annular gap between the mixed liquid inlet 116 and the spiral groove-shaped outer casing 117. The gas phase outlet cover 102 is provided with a central shaft sleeve. The central shaft 101 extends from the central shaft sleeve into the spiral groove-shaped outer casing 117, and after passing through the central shaft hole, the axial inlet 1071 of the spiral groove-shaped outer casing exits. Multi-stage discs are connected in series outside the central shaft 101 and are driven to rotate by the central shaft 101. In this embodiment, there are six stages of discs, which are sequentially connected in series at the spiral groove above the mixed liquid inlet. The new type of disc with rectangular protrusions can enhance the liquid capture capacity in high gas-content wells and efficiently aggregate gas. The spiral grooves on the inner wall of the spiral groove-shaped outer casing can realize the flow guidance function, which helps the liquid flow downward and realizes efficient gas-liquid separation in high gas-content wells. The six levels of discs are: Level 6 Disc 104, Level 5 Disc 105, Level 4 Disc 106, Level 3 Disc 107, Level 2 Disc 108, and Level 1 Disc 109.

[0019] Traditional separation methods often suffer from low efficiency and incomplete separation when handling fluids with high gas content. This not only affects extraction efficiency but can also damage equipment and increase maintenance costs. In this invention, the discs generate stronger centrifugal force during high-speed rotation, effectively capturing and separating the liquid. The special design of the disc surface increases the contact area and residence time between the liquid and the disc surface, improving liquid capture capacity and significantly increasing separation efficiency. A multi-stage disc stacking method is used, with each stage further separating the fluid, thus achieving multi-stage capture. The multi-stage disc design helps to progressively reduce the liquid content in the fluid, improving overall separation efficiency. A spiral groove design is added to the inner wall of the separation device's outer shell, which facilitates smooth downward flow of the liquid along the inner wall. The guiding effect of the spiral groove reduces liquid retention and accumulation inside the device, further improving separation efficiency.

[0020] The disc is an umbrella-shaped body with a central ring at the top. The umbrella-shaped body is radially and evenly arranged with a central hole 1041 and rectangular protrusions 1042. The central hole 1041 and rectangular protrusions 1042 are spaced apart. The mixed liquid moves from the central hole of the disc to the next level disc. The rotation of the disc generates centrifugal force, which gathers the gas phase in the mixed liquid to the middle, and the liquid is thrown to the side wall of the disc. The rectangular protrusions block some of the gas from flowing to the side wall of the disc with the liquid.

[0021] The gas phase outlet cover 102 is threadedly connected to the spiral groove type outer sleeve 117; the disc has a disc keyway 1043, the short shaft sleeve has a short shaft sleeve keyway 1101, and the central shaft has a central shaft keyway. The key is first installed on the central shaft keyway, and then the new disc is secured to the key through the disc keyway. The short shaft sleeve is connected to the key through the short shaft sleeve keyway and is secured between the two discs, fixing the discs on the central shaft; the mixed liquid inlet 116 is welded to the spiral groove type outer sleeve 117; the gas phase outlet cover 102 has four gas phase outlets; the mixed liquid inlet 116 has four mixed liquid inlets 1161; the spiral groove type outer sleeve 117 has an axial inlet 1171, a liquid phase outlet 1172, and a spiral groove 1173.

[0022] In operation, the central shaft is connected to the engine. The gas-liquid mixture enters the mixture inlet through the axial inlet. The engine drives the discs to rotate, and the rotation of the discs generates centrifugal force in the liquid, causing gas-liquid separation. Water, after being captured by multiple stages of discs, is thrown against the inner wall of the device and flows downwards from the liquid phase outlet, while the separated gas is discharged upwards from the four gas phase outlets. The outer shell is equipped with a spiral groove structure, with the spiral groove direction along the rotation direction of the mixture. During the gas-liquid separation process, this helps the liquid flow downwards along the inner wall. Rectangular protrusions are added to the discs to prevent some gas from flowing towards the side wall with the liquid, increasing the contact area and residence time between the liquid and the disc surface, and improving the liquid capture capacity.

[0023] The present invention is described in detail below with reference to the accompanying drawings: like Figure 1As shown, this dynamic gas-liquid separation device for high gas content well injection and production includes a central shaft 101, a gas phase outlet cover 102, a gas phase outlet 1021, a fixed sleeve 103, a short shaft sleeve, a long shaft sleeve 115, a mixed liquid inlet 116, a spiral groove outer sleeve 117, an axial inlet 1171, and a liquid phase outlet 1172. In this embodiment, the short shaft sleeve has five stages: the fifth stage short shaft sleeve 110, the fourth stage short shaft sleeve 111, the third stage short shaft sleeve 112, the second stage short shaft sleeve 113, and the first stage short shaft sleeve 114. The device is placed vertically and operates in a vertical state. The mixed liquid enters the cavity through the axial inlet 1171 and then enters the device through the mixed liquid inlet 1161. The motor drives the discs 104-109 to rotate and separate the gas and liquid phases. The gas phase is gathered in the middle by the discs and discharged from the gas phase outlet 1021, while the water phase is thrown to the side wall and flows down, and finally discharged from the liquid phase outlet 1172 and injected back into the ground.

[0024] See Figure 2 As shown, the central shaft keyway 1011 and key 118 serve as the main components for fixing the disc, while the key is used to fix the new type of disc to the short shaft sleeve and the long shaft sleeve.

[0025] like Figure 3 As shown, the disc has a new type of disc center hole 1041, through which the mixture flows to the next stage disc. The rotation of the disc generates centrifugal force, which gathers the gas phase to the center and throws the liquid to the side wall. The new disc has rectangular protrusions 1042 on the upper and lower surfaces, which can prevent some of the gas from flowing to the side wall with the liquid, thus improving the separation efficiency. At the same time, there is a new type of disc keyway 1043, which facilitates installation and fixation on the central shaft.

[0026] like Figure 4 As shown, the inner wall of the spiral groove type shell is provided with an axial inlet 1171, through which the mixed liquid enters the separator. The spiral groove 1173 is provided, which optimizes the flow path of the fluid and greatly promotes the smooth downward flow of the liquid along the side wall of the shell, thereby improving the liquid phase separation efficiency and time efficiency.

[0027] like Figure 5 As shown, the short shaft sleeve has a short shaft sleeve keyway 1101, which is used to install the key and to fix the new type of disc.

[0028] like Figure 6 As shown, the liquid inlet device has a liquid inlet hole 1161, and the liquid mixture enters the inner cavity to complete gas-liquid separation.

[0029] This invention ingeniously utilizes the rotation mechanism of discs to achieve efficient separation of gas and liquid through the generation of powerful centrifugal force. During rotation, gas is effectively gathered to the center of the disc and flows upward, eventually exiting smoothly from the gas phase outlet; while the liquid phase is thrown against the disc sidewalls and then flows smoothly downward along the inner wall of the outer shell with spiral grooves until it exits from the liquid phase outlet, achieving the purpose of reinjection underground. The special texture and structure of the novel disc surface endow it with extremely strong coalescence and droplet capture capabilities. Driven by high-speed rotation, the disc can quickly capture and coalesce tiny droplets, ensuring that they do not escape with the gas. In addition, the multi-stage disc configuration further enhances the coalescence efficiency and significantly improves the liquid capture capability, thereby greatly improving the overall separation efficiency. The device has a simple and clear structural design, requiring no complex maintenance procedures to achieve efficient and stable operation. At the same time, its separation time is extremely short, enabling rapid and efficient separation of the gas and liquid phases under high gas content conditions, ensuring the continuity and efficiency of the mining process. Therefore, this device is undoubtedly a dynamic gas-liquid high-efficiency separation device specifically designed for high gas-content downhole environments. Its emergence will bring a more efficient and reliable solution to the oilfield development field. This invention features a simple structure, high separation efficiency, and can achieve efficient gas-liquid two-phase separation under high gas content conditions. It is a separation device suitable for dynamic gas-liquid separation in high gas-content downhole wells during both injection and production.

Claims

1. A dynamic gas-liquid separation device for high gas content well injection and production in the same well, characterized in that: This dynamic gas-liquid separation device for high gas content well injection and production includes a central shaft, a gas phase outlet cover, multi-stage discs, a mixed liquid inlet, and a spiral groove-shaped outer sleeve. The upper end of the spiral groove-shaped outer sleeve is connected to the gas phase outlet cover. The inner wall of the spiral groove-shaped outer sleeve has spiral grooves, the direction of which is along the rotation direction of the mixed liquid. The spiral grooves extend to the bottom of the spiral groove-shaped outer sleeve. An axial inlet is set at the center of the bottom of the sleeve. A liquid phase outlet is set near the bottom of the spiral groove-shaped outer sleeve. The mixed liquid inlet is a cylindrical body with an open bottom and is fixed to the bottom of the spiral groove-shaped outer sleeve. The top of the mixed liquid inlet has a central shaft hole and a mixed liquid inlet. There is an annular gap between the mixed liquid inlet and the spiral groove-shaped outer sleeve. The gas phase outlet cover is equipped with a central shaft sleeve. The central shaft extends from the central shaft sleeve into the spiral groove-shaped outer sleeve, passes through the central shaft hole, and exits from the axial inlet of the spiral groove-shaped outer sleeve. The multi-stage discs are connected in series outside the central shaft and are driven to rotate by the central shaft. The multi-stage discs are set at the spiral groove above the mixed liquid inlet.

2. The dynamic gas-liquid separation device for high gas content well injection and production in the same well as described in claim 1, characterized in that: The disc is an umbrella-shaped body with a central ring at the top. The umbrella-shaped body is radially and evenly arranged with a central hole and rectangular protrusions. The central hole and rectangular protrusions are spaced apart. The mixture moves from the central hole to the next level disc. The rotation of the disc generates centrifugal force, which gathers the gas phase in the mixture to the middle, while the liquid is thrown to the side wall of the disc. The rectangular protrusions prevent some of the gas from flowing with the liquid to the side wall of the disc.

3. The dynamic gas-liquid separation device for high gas content well injection and production in the same well as described in claim 2, characterized in that: The disc has a disc keyway, the short shaft sleeve has a short shaft sleeve keyway, and the central shaft has a central shaft keyway. The key is installed on the central shaft keyway. The disc is held on the key through the disc keyway. The short shaft sleeve is connected to the key through the short shaft sleeve keyway. The short shaft sleeve is held between two adjacent discs, fixing the disc on the central shaft.

4. The dynamic gas-liquid separation device for high gas content well injection and production in the same well as described in claim 3, characterized in that: The gas phase outlet cover is connected to the spiral groove sleeve by threads. The gas phase outlet cover is provided with four gas phase outlets, which are evenly arranged around the central shaft sleeve.

5. The dynamic gas-liquid separation device for high gas content well injection and production in the same well as described in claim 4, characterized in that: The mixture inlet is welded to the spiral groove type outer sleeve. The top of the mixture inlet cylinder has four mixture inlets, which are evenly arranged around the central shaft hole. The top of the mixing inlet has an outer rim relative to the body of the cylinder.

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