A slug flow catcher

Abstract

A slug flow collector comprises a tank body and a gas phase outlet and a liquid phase outlet arranged on the tank body, a liquid stabilizing deflection assembly and a gas mist collector installed in the tank body, the slug flow collector is a horizontal structure, that is, the tank body is placed horizontally; a slug liquid inlet is installed through the head on one side of the tank body, and an energy dissipation pipe is installed through the tank body and on the same center line as the slug liquid inlet, and the terminal outlet of the energy dissipation pipe extends to the inner wall of the head on the other side of the tank body; the energy dissipation pipe is composed of a first-stage expansion pipe at the starting part, a second-stage expansion pipe at the middle and rear part, and a terminal half-pipe at the tail end, which are detachably connected end to end in sequence; the first-stage expansion pipe is expanded to 1.25 times the diameter of the slug liquid inlet. The present invention has a simple structure, sufficient gas-liquid separation space, a stable internal gas-liquid flow field, can effectively promote gas-liquid separation and slug flow capture, solves the impact of mixed pipeline slug flow on downstream facilities, and ensures stable and safe production operation.

Description

Technical Field

[0001] The invention relates to a processing device for slug flow of oil and gas mixed transmission pipeline, which is suitable for capturing and eliminating slug flow in surface gathering and transportation of oil and gas fields. Background Art

[0002] With the development of offshore and onshore oil and gas fields and large condensate gas fields, multiphase flow mixed transportation technology has been continuously developed. In the process of multiphase flow mixed transportation, long-distance transportation and pipeline turning and shearing usually produce slug flow; in the process of oil and gas field development, slug flow can also be generated due to oil well operation and maintenance. Severe slug flow can cause a series of problems such as hydraulic shock, liquid level fluctuation and blockage to the oil and gas separation equipment at the end of the pipeline and subsequent process facilities, making it difficult for downstream process facilities to operate normally.

[0003] Chinese patent 201710543940.9 discloses a finger-shaped slug flow dissipation separation device, which continuously reduces the velocity and momentum of the fluid by setting a diverter pipe and a finger-shaped branch pipe, while dissipating the energy of the slug, and finally sends the separated gas and liquid phases to downstream facilities through gas and liquid collecting manifolds. The device occupies a large area and lacks structural components for effectively handling slug flow.

[0004] Chinese patent 201620777487.9 discloses a slug flow collector, which is designed for tangential feeding, with a swirl cylinder installed in a vertical structure and a TP component with a radial channel installed in the upper space. The internal gas-liquid separation space of the device is limited, and the processing capacity and the final gas-liquid separation effect are limited.

[0005] Chinese patent ZL.201810786014.9 is a slug flow catcher developed based on the slug flow mechanism and characteristics. The main function of the slug flow catcher is to absorb energy and capture liquid plugs. However, the spiral distributor inside the slug flow catcher has serious overflow and the gas-liquid coalescing internals have uneven liquid flow distribution. Summary of the invention

[0006] The present invention provides a slug flow catcher, which has a stable internal gas-liquid flow field, can effectively promote gas-liquid separation and slug flow capture, solves the impact of slug flow in mixed pipelines on downstream facilities, and ensures stable and safe production operation.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is:

[0008] A slug flow collector comprises a tank body and a gas phase outlet and a liquid phase outlet arranged on the tank body, a liquid stabilizing and deflecting assembly and a gas mist collector installed in the tank body, the slug flow collector is a horizontal structure, that is, the tank body is placed horizontally; a slug liquid inlet is installed through the head on one side of the tank body, and an energy dissipation pipe is installed through the tank body and on the same center line as the slug liquid inlet, and the terminal outlet of the energy dissipation pipe extends to the inner wall of the head on the other side of the tank body; the energy dissipation pipe is formed by a primary expansion pipe at the starting part, a secondary expansion pipe at the middle and rear part, and a terminal half-pipe at the tail end part, which are detachably connected in sequence; the primary expansion pipe is expanded to 1.25 times the diameter of the slug liquid inlet, and the pipe length of the primary expansion pipe is 2 / 3 of the length of the tank body; the pipe length of the secondary expansion pipe 10 is 1 / 3 of the length of the tank body.

[0009] The first-level expansion pipe is a first-level eccentric expansion pipe composed of a first-level eccentric reducer and a first-level expansion pipe; a curved energy dissipator is installed in the first-level expansion pipe, and the first curved energy dissipator is installed at 1 / 3 of the first-level expansion pipe; the second curved energy dissipator is located at 4 / 5 of the first-level expansion pipe; the curved energy dissipator is a spiral curved plate with a spiral length of 0.5~1 pitch.

[0010] The curved surface of the first curved surface energy dissipator is a clockwise curved surface, and the curved surface of the second curved surface energy dissipator is a counterclockwise curved surface.

[0011] The secondary expansion pipe is composed of a secondary eccentric reducer and a secondary expansion pipe; the diameter of the secondary expansion pipe is 1.25 times that of the primary expansion pipe; a flow stabilizer is installed on the secondary expansion pipe, and the flow stabilizer is located at 1 / 3 of the secondary expansion pipe.

[0012] The flow stabilizing energy dissipator is composed of a plurality of blades rotating around the center point of the secondary expansion pipe, and the blades are arranged at 30-45 degrees with respect to the axis of the secondary expansion pipe.

[0013] The end half-pipe of the energy dissipation pipe starts at 2 / 3 of the secondary expansion pipe and ends at the end of the energy dissipation pipe; the end half-pipe ends at a distance of 100 mm from the inner wall of the head.

[0014] An anti-collision baffle is provided on the tank head wall directly facing the pipeline fluid outlet of the terminal half-pipe of the energy dissipation pipe.

[0015] A liquid guide plate is provided on the front end energy dissipation pipe at the beginning of the terminal half-pipe pipeline. The upper edge of the liquid guide plate is flush with the horizontal center line of the energy dissipation pipe, the lower edge of the liquid guide plate is flush with the low liquid level in the tank body, and both sides of the liquid guide plate are fixedly connected to the inner wall of the tank body.

[0016] The liquid flow stabilizing and deflecting assembly includes a liquid flow stabilizing plate and a liquid deflecting plate arranged in sequence along the fluid flow direction; the upper edge of the liquid flow stabilizing plate is flush with the center line of the energy dissipation tube in the vertical direction, and a liquid channel is formed between the bottom edge of the liquid flow stabilizing plate and the tank body; the upper edge of the liquid flow stabilizing plate is located between the upper edge and the bottom edge of the liquid flow stabilizing plate in the vertical direction, and the bottom of the liquid deflecting plate is connected to the bottom of the tank body.

[0017] The gas mist collector is arranged in the gas phase space in the equipment and close to the gas phase outlet; the gas phase outlet and the liquid phase outlet are respectively installed at the upper and lower parts of the tank body close to the slug liquid inlet end; a gas guide plate is installed at the gas phase outlet, and a liquid vortex breaker is installed at the liquid phase outlet.

[0018] In the present invention, the slug liquid enters the energy dissipation pipe in the slug flow collector through the slug liquid inlet, slows down the flow rate in the first expansion pipe of the energy dissipation pipe, uses eccentric expansion pipe, and the gas phase in the pipe overflows from the liquid phase. The slug liquid in the pipe does not change the flow direction and gradually stabilizes and tends to the continuous phase. The slug liquid passes through the first curved energy dissipator in the energy dissipation pipe to dissipate energy, and the flow state of the fluid changes from axial flow to clockwise spiral flow; the fluid passes through the second curved energy dissipator, and the fluid changes from the original clockwise axial flow energy dissipation to counterclockwise axial flow energy dissipation. The change in fluid direction is the energy dissipation process. The fluid after energy dissipation enters the second eccentric expansion pipe in the energy dissipation pipe to continue to slow down the flow rate, and uses eccentric expansion pipe again to make the gas phase in the pipe continue to overflow from the liquid phase. The slug liquid in the pipe does not change the flow direction and gradually stabilizes and tends to the continuous phase. Micro-rotation energy dissipation is carried out through the steady flow energy dissipator, and enters the terminal half-pipe pipe for initial gas-liquid separation. The separated gas overflows into the gas phase space and is discharged from the gas phase outlet through the gas mist collector. The liquid obtained by gas-liquid separation flows to the bottom of the tank through the liquid guide, passes through the space between the liquid flow stabilizer and the tank body, and then passes through the liquid baffle to complete the baffle. After the liquid level is stabilized, it is finally discharged from the liquid phase outlet.

[0019] The present invention has a simple structure, sufficient gas-liquid separation space, a stable internal gas-liquid flow field, can effectively promote gas-liquid separation and slug flow capture, solves the impact of slug flow in mixed pipelines on downstream facilities, and ensures stable and safe production operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the structure of the present invention;

[0021] Figure 2 for Figure 1 Schematic diagram of top view;

[0022] Figure 3 It is a structural schematic diagram of the clockwise curved energy dissipator of the present invention;

[0023] Figure 4It is a schematic structural diagram of the counterclockwise curved energy dissipator of the present invention;

[0024] Figure 5 It is a schematic diagram of the three-dimensional structure of the flow-stabilizing energy dissipator of the present invention;

[0025] Figure 6 for Figure 5 Schematic diagram of the main structure;

[0026] Figure 7 This is a schematic diagram of the structure of the eccentric reducer of the present invention;

[0027] In the figure: 1—slug liquid inlet; 2—gas phase outlet; 3—liquid phase outlet; 4—demister; 5—first-stage expansion pipe 5-1 first-stage eccentric reducer; 5-2—first-stage expansion pipe 6—first curved energy dissipator; 7—second curved energy dissipator; 8—energy dissipation pipe; 9—tank body; 10—second-stage expansion pipe; 10-1-second-stage eccentric reducer; 10-2—second-stage expansion pipe; 11—flow stabilizing energy dissipator; 12—terminal half-pipe pipe; 13—liquid guide plate; 14—anti-collision baffle; 15—liquid flow stabilizing plate; 16—liquid baffle; 17—gas guide plate 18—liquid vortex breaker. DETAILED DESCRIPTION

[0028] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0029] like Figure 1 , Figure 2 As shown, a slug flow collector comprises a tank 9 and a gas phase outlet 2 and a liquid phase outlet 3 arranged on the tank body, a liquid stabilizing deflection assembly and a gas mist collector installed in the tank body, and the slug flow collector is a horizontal structure, that is, the tank body 9 is placed horizontally; a slug liquid inlet 1 is installed through the end cap of one side of the tank body 9, and an energy dissipation pipe 8 is installed through the tank body 9 on the same horizontal line as the slug liquid inlet 1, and the end outlet of the energy dissipation pipe 8 (the energy dissipation pipe 8 is supported by a pipe bracket installed on the inner wall of the tank body) extends to the inner wall of the end cap of the other side of the tank body 9; the energy dissipation pipe 8 is formed by a primary expansion pipe 5 at the starting part, a secondary expansion pipe 10 at the middle and rear part, and a terminal half-pipe pipeline 12 at the tail end part being connected end to end with bolts in sequence; the primary expansion pipe 5 is expanded to 1.25 times the diameter of the slug liquid inlet, and the pipe length of the primary expansion pipe 5 is 2 / 3 of the length of the tank body; the pipe length of the secondary expansion pipe 10 is 1 / 3 of the length of the tank body.

[0030] In the above, the radial position of the nozzle of the slug liquid inlet 1 should ensure that the bottom of the nozzle is flush with the high operating liquid level in the equipment.

[0031] like Figure 7As shown, the first-stage expansion pipe 5 is a first-stage eccentric expansion pipe composed of a first-stage eccentric reducer 5-1 and a first-stage expansion pipe 5-2; a curved energy dissipator is installed in the first-stage expansion pipe 5-2, and the first curved energy dissipator is installed at 1 / 3 of the first-stage expansion pipe; the second curved energy dissipator is located at 4 / 5 of the first-stage expansion pipe; the curved energy dissipator is a spiral curved panel with a spiral length of 0.5~1 pitch.

[0032] The use of a first-stage eccentric expansion pipe is beneficial to the overflow of the gas phase in the liquid in the pipeline, so that the plug liquid in the pipeline gradually stabilizes and tends to a continuous phase without changing the flow direction.

[0033] like Figure 3 , Figure 4 As shown, the curved surface of the first curved energy dissipator 6 is a clockwise curved surface, and the curved surface of the second curved energy dissipator 7 is a counterclockwise curved surface.

[0034] The slug fluid passes through the first curved energy dissipator 6 in the energy dissipation pipe to dissipate energy, and the flow state of the fluid changes from axial flow to clockwise spiral flow; the fluid passes through the second curved energy dissipator 7, and the fluid changes from the original clockwise axial flow energy dissipation to counterclockwise axial flow energy dissipation. The change of fluid direction is the energy dissipation process.

[0035] like Figure 7 As shown, the secondary expansion pipe 10 is a secondary eccentric expansion pipe consisting of a secondary eccentric reducer 10-1 and a secondary expansion pipe 10-2. The diameter of the secondary expansion pipe 10-2 is 1.25 times that of the primary expansion pipe 5-2; a flow stabilizing energy dissipator is installed on the secondary expansion pipe 10-2, and the flow stabilizing energy dissipator is located at 1 / 3 of the secondary expansion pipe 10-2.

[0036] like Figure 5 , Figure 6 As shown, the flow stabilizer is composed of a number of blades rotating around the center point of the secondary expansion pipe 10-2; and the blades are arranged at 30-45° with respect to the axis of the secondary expansion pipe 10-2, so that the fluid can be slightly dissipated without increasing the pressure drop, and the rotating blades have the function of diverting and stabilizing the flow.

[0037] After the first-stage eccentric expansion and the curved energy dissipator, the fluid enters the second-stage eccentric expansion pipe in the energy dissipator to continue to slow down the flow rate. The second-stage eccentric expansion pipe is used to make the gas phase in the pipe continue to overflow from the liquid phase. The slug liquid in the pipe does not change the flow direction and gradually stabilizes and tends to the continuous phase. Micro-rotation energy dissipation is carried out through the steady flow energy dissipator.

[0038] The end half pipe 12 of the energy dissipation pipe 8 starts at 2 / 3 of the secondary expansion pipe 10-2 and ends at the end of the energy dissipation pipe 8. The end half pipe ends at a distance of about 100 mm from the tank head.

[0039] The slug liquid enters the terminal half-pipe for initial gas-liquid separation. The separated gas overflows into the gas phase space and is discharged from the gas phase outlet through the gas mist collector. The liquid obtained by gas-liquid separation is diverted to the bottom of the tank through the liquid, passes through the space between the liquid flow stabilizer and the tank body, and then passes through the liquid baffle to complete the baffle. After the liquid level is stabilized, it is finally discharged from the liquid phase outlet.

[0040] An anti-collision baffle 14 is provided on the tank head wall facing the pipeline fluid outlet of the end half-pipe pipeline 12 of the energy dissipation pipe. The anti-collision baffle 14 reduces the momentum carried by the fluid on the one hand, and prevents gas and liquid from eroding the shell head on the other hand.

[0041] A liquid guide plate 13 is provided on the front end energy dissipation pipe at the beginning of the terminal half-pipe 12, the upper edge of the liquid guide plate 13 is flush with the horizontal center line of the energy dissipation pipe, the lower edge of the liquid guide plate 13 is flush with the low liquid level in the tank body, and both sides of the liquid guide plate 13 are fixedly connected to the inner wall of the tank body 9. The liquid guide plate 13 can guide the liquid and support the energy dissipation pipe at the same time.

[0042] The liquid flow stabilizing baffle assembly includes a liquid flow stabilizing plate 15 and a liquid baffle 16 arranged in sequence along the fluid flow direction; the upper edge of the liquid flow stabilizing plate 15 is flush with the center line of the energy dissipation tube in the vertical direction, and a liquid channel is formed between the bottom edge of the liquid flow stabilizing plate 15 and the tank body; the upper edge of the liquid baffle 16 is located between the upper edge and the bottom edge of the liquid flow stabilizing plate 15 in the vertical direction, and the bottom of the liquid baffle 16 is connected to the bottom of the tank body. The liquid flow stabilizing baffle assembly reduces the kinetic energy carried by the liquid, and the liquid flows stably after turning over the baffle.

[0043] The gas mist collector 4 is arranged in the gas phase space in the equipment and near the gas phase outlet 2; the gas phase outlet 2 and the liquid phase outlet 3 are respectively installed at the upper and lower parts of the tank body near the slug liquid inlet end; a gas guide plate 17 is installed at the gas phase outlet 2, and a liquid vortex breaker 18 is installed at the liquid phase outlet 3 to prevent vortices from forming at the gas and liquid outlets. The gas mist collector 4 and the liquid vortex breaker 18 are both conventionally used products.

[0044] In the present invention, the "downstream" refers to the relative arrangement relationship of components with respect to the material flow direction, and the meaning of this term is understood by those skilled in the art.

[0045] In the slug flow catcher of the present invention, the slug liquid enters the energy dissipation pipe in the slug flow catcher through the slug liquid inlet, and the flow velocity is slowed down in the primary expansion pipe of the energy dissipation pipe. By using eccentric expansion pipe, the gas phase in the pipe overflows from the liquid phase, and the slug liquid in the pipe does not change the flow direction and gradually stabilizes and tends to the continuous phase. The slug liquid passes through the first curved energy dissipator in the energy dissipation pipe to dissipate energy, and the flow state of the fluid is changed from axial flow to clockwise spiral flow; the fluid passes through the second curved energy dissipator, and the fluid changes from the original clockwise axial flow energy dissipation to counterclockwise axial flow energy dissipation. The change in fluid direction is the energy dissipation process. The fluid after energy dissipation enters the secondary expansion pipe in the energy dissipation pipe to continue to slow down the flow velocity. By using eccentric expansion pipe, the gas phase in the pipe continues to overflow from the liquid phase, and the slug liquid in the pipe does not change the flow direction and gradually stabilizes and tends to the continuous phase. Micro-rotation energy dissipation is carried out through the steady flow energy dissipator, and the fluid enters the terminal half-pipe pipe for initial gas-liquid separation. The separated gas overflows into the gas phase space and is discharged from the gas phase outlet through the gas mist collector. The liquid obtained by gas-liquid separation flows to the bottom of the tank through the liquid guide, passes through the space between the liquid flow stabilizer and the tank body, and then passes through the liquid baffle to complete the baffle. After the liquid level is stabilized, it is finally discharged from the liquid phase outlet.

[0046] The present invention has a simple structure, sufficient gas-liquid separation space, a stable internal gas-liquid flow field, can effectively promote gas-liquid separation and slug flow capture, solves the impact of slug flow in mixed pipelines on downstream facilities, and ensures stable and safe production operation.

Claims

1. A slug flow collector, comprising a tank body and a gas phase outlet and a liquid phase outlet arranged on the tank body, a liquid stabilizing baffle assembly and a gas mist collector installed in the tank body, It is characterized in that The slug flow collector is a horizontal structure, that is, the tank body (9) is placed horizontally; a slug liquid inlet (1) is installed through a head on one side of the tank body (9), and an energy dissipation pipe (8) is installed through the tank body (9) on the same center line as the slug liquid inlet (1), and the terminal outlet of the energy dissipation pipe (8) extends to the inner wall of the head on the other side of the tank body (9); the energy dissipation pipe (8) is composed of a first-stage expansion pipe (5) at the starting part, a second-stage expansion pipe (10) at the middle and rear part, and a terminal half pipe (12) at the tail end, which are connected in sequence end to end in a detachable manner; the first-stage expansion pipe is expanded to 1.25 times the diameter of the slug liquid inlet. , and the pipe length of the first-stage expansion pipe (5) is 2 / 3 of the length of the tank body; the pipe length of the second-stage expansion pipe (10) is 1 / 3 of the length of the tank body; the first-stage expansion pipe (5) is a first-stage eccentric expansion pipe composed of a first-stage eccentric reducer (5-1) and a first-stage expansion pipe (5-2); a curved energy dissipator is installed in the first-stage expansion pipe (5-2), and the first curved energy dissipator (6) is installed at 1 / 3 of the first-stage expansion pipe; the second curved energy dissipator (7) is located at 4 / 5 of the first-stage expansion pipe; the curved energy dissipator is a spiral curved plate, and the spiral length is 0.5~1 pitch.

2. A slug catcher according to claim 1, It is characterized in that The curved surface of the first curved surface energy dissipator is a clockwise curved surface, and the curved surface of the second curved surface energy dissipator is a counterclockwise curved surface.

3. A slug catcher according to claim 1, It is characterized in that The secondary expansion pipe (10) is a secondary eccentric expansion pipe composed of a secondary eccentric reducer (10-1) and a secondary expansion pipe (10-2); the diameter of the secondary expansion pipe (10-2) is 1.25 times that of the primary expansion pipe (5-2); a flow stabilizing energy dissipator is installed on the secondary expansion pipe (10-2), and the flow stabilizing energy dissipator is located at 1 / 3 of the secondary expansion pipe (10-2).

4. A slug catcher according to claim 3, It is characterized in that The flow stabilizing energy dissipator is composed of a plurality of blades rotating around the center point of the secondary expansion pipe (10-2), and the blades are arranged at 30-45 degrees to the axis of the secondary expansion pipe (10-2).

5. A slug catcher according to claim 1, It is characterized in that The end half-pipe pipeline (12) of the energy dissipation pipe (8) starts at 2 / 3 of the secondary expansion pipe (10-2) and ends at the end of the energy dissipation pipe (8); the end half-pipe pipeline ends at a distance of 100 mm from the inner wall of the end cap.

6. A slug catcher according to claim 5, It is characterized in that An anti-collision baffle (14) is provided on the tank head wall directly facing the pipeline fluid outlet of the end half-pipe pipeline (12) of the energy dissipation pipe.

7. A slug catcher according to any one of claims 1 to 6, It is characterized in that A liquid guide plate (13) is provided on the front end energy dissipation pipe at the beginning of the end half-pipe pipeline (12); the upper edge of the liquid guide plate (13) is flush with the horizontal center line of the energy dissipation pipe (8); the lower edge of the liquid guide plate (13) is flush with the low liquid level in the tank body; and both sides of the liquid guide plate (13) are fixedly connected to the inner wall of the tank body (9).

8. A slug catcher according to claim 7, It is characterized in that The liquid flow stabilizing and deflecting assembly comprises a liquid flow stabilizing plate (15) and a liquid deflecting plate (16) which are arranged in sequence along the flow direction of the fluid; the upper edge of the liquid flow stabilizing plate (15) is flush with the center line of the energy dissipation pipe in the vertical direction, and a liquid channel is formed between the bottom edge of the liquid flow stabilizing plate (15) and the tank body; the upper edge of the liquid deflecting plate (16) is located between the upper edge and the bottom edge of the liquid flow stabilizing plate (15) in the vertical direction, and the bottom of the liquid deflecting plate (16) is connected to the bottom of the tank body.

9. A slug catcher according to claim 8, It is characterized in that The gas mist collector (4) is arranged in the gas phase space in the device and is close to the gas phase outlet (2); the gas phase outlet (2) and the liquid phase outlet (3) are respectively installed at the upper and lower parts of the tank body close to the slug liquid inlet end; a gas guide plate (17) is installed at the gas phase outlet (2), and a liquid vortex breaker (18) is installed at the liquid phase outlet (3).

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