Novel three-phase metering device for oil field wellhead

Abstract

The utility model relates to the field of gas-liquid separation, and discloses a novel three-phase metering device for a wellhead of an oil field. The novel three-phase metering device for the oilfield wellhead comprises an inlet vertical pipe and an outlet vertical pipe which are arranged in a communicated mode, a mist catcher is arranged in the inlet vertical pipe, and the inlet vertical pipe is divided into an inlet pipe gas phase area and an inlet pipe liquid phase area by the mist catcher; a floating sealing piece is arranged in the outlet vertical pipe and divides the outlet vertical pipe into an outlet pipe gas phase area and an outlet pipe liquid phase area; the outlet pipe liquid phase area is communicated with the inlet pipe liquid phase area through a liquid flow pipe, and the outlet pipe gas phase area is communicated with the inlet pipe gas phase area through a gas flow pipe; through the inlet vertical pipe and the outlet vertical pipe which are communicated with each other as well as the design of the mist catcher and the floating sealing piece, a gas phase and a liquid phase in crude oil can be effectively separated and output, the structure is simple, and the maintenance cost is low.

Description

Technical Field

[0001] The utility model relates to the field of gas-liquid separation, in particular to a novel three-phase metering device for oil field wellheads. Background Art

[0002] Accurate measurement of three-phase flow is an essential link in the oil well production process. Currently, there are two types of metering equipment for three-phase flow: separation metering and non-separation metering. Among them, in the separation metering method, most designs use a large gas-liquid separation tank for gas-liquid separation. The gas-liquid separation tank used is a pressure vessel with a high risk factor, a complex structure, and high maintenance and use costs. Once a key component fails, the entire device cannot work normally and needs to be shut down for maintenance, affecting the development of oil well operations. Utility Model Content

[0003] The utility model aims to provide a novel three-phase metering device for oil field wellhead, which can effectively perform gas-liquid separation metering and has a simple structure and low maintenance cost.

[0004] In order to solve the above technical problems, the implementation method of the utility model provides a technical solution as follows:

[0005] A novel three-phase metering device for oilfield wellheads comprises an inlet riser and an outlet riser which are connected and arranged in communication. A mist catcher is arranged inside the inlet riser, and the mist catcher divides the inlet riser into an inlet pipe gas phase area and an inlet pipe liquid phase area; a floating seal is arranged inside the outlet riser, and the floating seal divides the outlet riser into an outlet pipe gas phase area and an outlet pipe liquid phase area; the outlet pipe liquid phase area is connected with the inlet pipe liquid phase area through a liquid flow pipe, and the outlet pipe gas phase area is connected with the inlet pipe gas phase area through an air flow pipe; the outlet pipe gas phase area is connected with a gas phase pipeline for gas output, a gas meter is connected to the gas phase pipeline, the outlet pipe liquid phase area is connected with a liquid phase pipeline for liquid output, and a liquid meter is connected to the liquid phase pipeline.

[0006] Furthermore, the liquid phase region of the inlet pipe is provided with a flow-breaking plate, and the flow-breaking plate is located above the connecting end of the liquid flow pipe and the liquid phase region of the outlet pipe.

[0007] Furthermore, the liquid phase region of the outlet pipe is provided with a vortex breaker, and the vortex breaker is located above the connection position between the liquid phase pipeline and the liquid phase region of the outlet pipe.

[0008] Furthermore, a two-phase buffer tube is provided between the outlet vertical pipe and the inlet vertical pipe, and a mist collector is provided in the two-phase buffer tube. The mist collector divides the two-phase buffer tube into a gas phase buffer zone and a liquid phase buffer zone. The gas phase buffer zone is connected to the gas phase zone of the outlet pipe through an air flow tube, and the liquid phase buffer zone is connected to the liquid phase zone of the outlet pipe through a liquid flow tube.

[0009] Furthermore, a plurality of two-phase buffer tubes are provided between the outlet vertical tube and the inlet vertical tube, and mist collectors are provided in the two-phase buffer tubes. The mist collectors divide the two-phase buffer tubes into a gas phase buffer zone and a liquid phase buffer zone. The liquid phase buffer zones between the plurality of two-phase buffer tubes are connected in sequence through liquid flow tubes, and the gas phase buffer zones between the plurality of two-phase buffer tubes are connected in sequence with adjacent liquid phase buffer zones through air flow tubes.

[0010] Furthermore, the connection position between the gas flow pipe and the gas phase zone and gas phase buffer zone of the inlet pipe is arranged near the upper end of the mist collector, and the connection position between the gas flow pipe and the liquid phase buffer zone is arranged near the lower end of the mist collector.

[0011] Furthermore, a pressure regulator is provided on the liquid phase pipeline, and the pressure regulator is arranged downstream of the liquid meter to adjust the pressure of the liquid phase pipeline or close the liquid phase pipeline.

[0012] Further, it includes a vortex inlet pipe, which includes a vertical pipe and an inclined pipe. The lower end of the vertical pipe is connected to the input port, the upper end of the vertical pipe is connected to the inclined pipe, and the horizontal lower end of the inclined pipe is connected to the side wall of the inlet vertical pipe and is connected to the inlet vertical pipe.

[0013] Furthermore, it comprises a one-way valve, the output ends of the liquid phase pipeline and the gas phase pipeline are connected to one end of a manifold, the other end of the manifold is connected to the output port, and the one-way valve is connected to the manifold.

[0014] Furthermore, it includes an overpressure protector, which is connected and arranged between the input port and the output port.

[0015] Compared with the prior art, the novel three-phase metering device for oil field wellhead provided by the utility model can effectively separate and output the gas phase and liquid phase in crude oil through the design of interconnected inlet vertical pipe and outlet vertical pipe, as well as mist collector and floating seal, and has a simple structure, a high safety factor and a low maintenance cost; the separation effect of the gas phase and liquid phase in crude oil is further increased through the design of flow breaker and vortex preventer, the gas-liquid separation effect is increased through the design of two-phase buffer tube, the separated gas is subjected to multi-layer filtration, the liquid content in the gas is reduced, which is beneficial to improve the accuracy of separation and metering of the gas phase and liquid phase in crude oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0017] Figure 1This is a front view of a novel three-phase metering device for oil field wellheads in one embodiment of the utility model;

[0018] Figure 2 It is a schematic diagram of a novel three-phase metering device for oil field wellhead in one embodiment of the utility model;

[0019] Figure 3 It is a left view of a novel three-phase metering device for oil field wellhead in one embodiment of the utility model;

[0020] Figure 4 It is a right view of a novel three-phase metering device for oil field wellhead in one embodiment of the utility model.

[0021] Explanation of the reference numerals: 1. swirl inlet pipe; 11. vertical pipe; 12. inclined pipe; 2. inlet vertical pipe; 21. flow-breaking plate; 22. gas phase area of ​​inlet pipe; 23. liquid phase area of ​​inlet pipe; 3. two-phase buffer pipe; 31. first slow-flow pipe; 32. second slow-flow pipe; 33. third slow-flow pipe; 34. fourth slow-flow pipe; 4. outlet vertical pipe; 41. vortex breaker; 42. floating seal; 43. gas phase pipeline; 431. gas outlet; 44. liquid phase pipeline; 45. gas phase area of ​​outlet pipe; 46. liquid phase area of ​​outlet pipe; 5. mist collector; 6. gas flow pipe; 7. liquid flow pipe; 8. gas meter; 9. liquid meter; 101. input port; 102. output port; 103. pressure regulator; 104. overpressure protector; 105. one-way valve. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the utility model clearer, the various embodiments of the utility model will be described in detail below with reference to the accompanying drawings. However, it can be understood by those skilled in the art that in the various embodiments of the utility model, many technical details are provided in order to enable readers to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical schemes claimed for protection in the claims of the present application can be implemented.

[0023] like Figure 1-4As shown, the utility model provides a novel three-phase metering device for oil field wellhead, comprising an inlet vertical pipe 2 and an outlet vertical pipe 4 which are connected to each other, a mist collector 5 is arranged inside the inlet vertical pipe 2, and the mist collector 5 divides the inlet vertical pipe 2 into an inlet pipe gas phase zone 22 and an inlet pipe liquid phase zone 23, the inlet pipe gas phase zone 22 is located above the mist collector 5, and the inlet pipe liquid phase zone 23 is located below the mist collector 5; the crude oil at the oil field wellhead flows to the cyclone inlet pipe 1 through the input port 101, and the cyclone inlet pipe 1 is connected with the inlet pipe liquid phase zone 23, after the crude oil flows into the inlet pipe liquid phase zone 23, the liquid contained in the crude oil flows downwardly into the inlet pipe liquid phase zone 23, and the precipitated gas flows upwardly through the mist collector 5 and then flows into the inlet pipe gas phase zone 22. Preferably, the cyclone inlet pipe 1 includes a vertical pipe 11 and an inclined pipe 12, the lower end of the vertical pipe 11 is connected to the input port 101, the upper end of the vertical pipe 11 is connected to the inclined pipe 12, and the horizontal lower end of the inclined pipe 12 is connected to the side wall of the inlet vertical pipe 2 and is connected to the inlet vertical pipe 2. A floating seal 42 is provided inside the outlet vertical pipe 4, and the floating seal 42 divides the outlet vertical pipe 4 into an outlet pipe gas phase area 45 and an outlet pipe liquid phase area 46, that is, the outlet pipe gas phase area 45 is located above the floating seal 42, and the outlet pipe liquid phase area 46 is located below the floating seal 42; the outlet pipe liquid phase area 46 is connected to the inlet pipe liquid phase area 23 through the liquid flow pipe 7, and the outlet pipe gas phase area 45 is connected to the inlet pipe gas phase area 22 through the gas flow pipe 6; the outlet pipe gas phase area 45 is connected to the gas phase pipeline 43 for gas output, and the outlet pipe liquid phase area 46 is connected with the liquid phase pipeline 44 and outputs liquid. Preferably, a gas meter 8 is provided on the gas phase pipeline 43, and the gas meter 8 is used to measure the gas flow in the gas phase pipeline 43. In one embodiment, the gas meter 8 is an ultrasonic flow meter. A liquid meter 9 is provided on the liquid phase pipeline 44, and the liquid meter 9 is used to measure the liquid flow in the liquid phase pipeline 44. In one embodiment, the liquid meter 9 is a mass flow meter, and the mass flow meter can measure the content of oil and water components in the liquid phase to complete the oil and water separation measurement.

[0024] In the above embodiment, the mist collector 5 is arranged using a structure that can be easily implemented in the prior art. For example, the mist collector 5 is formed of metal weaving, and multiple layers of metal weaving structures are stacked to form the mist collector 5. The mist collector 5 is used to filter the liquid in the gas and reduce the liquid content in the gas. Preferably, the mist collector 5 filters droplets larger than 100 microns in the gas.

[0025] In one embodiment, the inlet pipe liquid phase zone 23 is provided with a flow-breaking plate 21, and the flow-breaking plate 21 can divert the liquid flowing to the inlet pipe liquid phase zone 23, so that the gas in the liquid is further precipitated, and the precipitated gas enters the inlet pipe gas phase zone 22 after being filtered by the mist collector 5; the connecting interface between the cyclone inlet pipe 1 and the inlet vertical pipe 2 is located above the flow-breaking plate 21, and the flow-breaking plate 21 is made of a single-layer orifice plate, and is roughly conical as a whole, with the top of the cone facing upward, and the connection position of the liquid flow pipe 7 and the inlet pipe liquid phase zone 23 relative to the liquid flow direction is located below the flow-breaking plate 21, and the connection position of the liquid flow pipe 7 and the outlet pipe liquid phase zone 46 is located below the vortex preventer 41.

[0026] In one embodiment, the outlet pipe liquid phase zone 46 is provided with a vortex breakers 41, and the vortex breakers 41 are located above the connection position between the liquid phase pipeline 44 and the outlet pipe liquid phase zone 46 to prevent the liquid phase from causing a vortex state when flowing out and bringing gas into the liquid meter 9. The vortex breakers 41 are used to prevent the vortex effect caused by the liquid flow. The vortex breakers 41 can adopt various means in the prior art, such as a single-piece vortex breakers 41, one end of the vortex breakers 41 is perpendicular to the pipe wall, and the other end is extended toward the central axis direction, so that the plane of the vortex breakers 41 is roughly perpendicular to the vortex direction of the water flow, thereby cutting off the vortex and preventing the formation of the vortex. The vortex breakers 41 are multi-piece, for example, two vortex breakers are used to be vertically crossed and fixedly connected to form a vortex breakers 41 with a T-shaped or cross-shaped cross section.

[0027] In one embodiment, a two-phase buffer tube 3 is further provided between the outlet vertical pipe 4 and the inlet vertical pipe 2. A mist collector 5 is provided inside the two-phase buffer tube 3. The mist collector 5 divides the two-phase buffer tube 3 into a gas phase buffer zone and a liquid phase buffer zone. The gas phase zone 22 of the inlet pipe is connected with the liquid phase buffer zone through the air flow tube 6, so that after the gas in the gas phase zone 22 of the inlet pipe enters the liquid phase buffer zone, it rises and passes through the mist collector 5 provided in the two-phase buffer tube 3 for filtration again before entering the gas phase buffer zone. The gas phase buffer zone is connected with the gas phase zone 45 of the outlet pipe through the air flow tube 6, and the liquid phase buffer zone is respectively connected with the liquid phase zone 46 of the outlet pipe and the liquid phase zone 23 of the inlet pipe through the liquid flow tube 7.

[0028] like Figure 1-4As shown, a plurality of two-phase buffer tubes 3 are further provided between the outlet vertical pipe 4 and the inlet vertical pipe 2. In one embodiment, there are four two-phase buffer tubes 3, which are used to optimize the separation effect of the gas phase and the liquid phase in the crude oil, and at the same time, perform multiple filtrations on the liquid in the gas to reduce the liquid content in the gas. The gas phase zone 22 of the inlet pipe is respectively connected with the adjacent liquid phase buffer zone of the first slow flow tube 31 and the liquid phase buffer zone of the second slow flow tube 32 through the gas flow tube 6. The gas phase buffer zone of the first slow flow tube 31 is connected with the liquid phase zone of the third slow flow tube 33 through the gas flow tube 6, and the gas phase buffer zone of the third slow flow tube 33 is connected with the gas phase zone 45 of the outlet pipe through the gas flow tube 6; the gas phase buffer zone of the second slow flow tube 32 is connected with the liquid phase buffer zone of the fourth slow flow tube 34 through the gas flow tube 6, and the gas phase buffer zone of the fourth slow flow tube 34 is connected with the outlet gas phase zone 45 through the gas flow tube 6. The inlet pipe gas phase zone 45 is connected, thereby completing the multi-layer filtration of the liquid in the precipitated gas; the inlet pipe liquid phase zone 23 is respectively connected with the adjacent first slow flow pipe 31 liquid phase buffer zone and the second slow flow pipe 32 liquid phase buffer zone through the liquid flow pipe 7, the third slow flow pipe 33 liquid phase zone is respectively connected with the first slow flow pipe 31 liquid phase buffer zone, the second slow flow pipe 32 liquid phase buffer zone, and the outlet pipe liquid phase zone 46 through the liquid flow pipe 7, the fourth slow flow pipe 34 liquid phase zone is respectively connected with the second slow flow pipe 32 liquid phase buffer zone and the outlet pipe liquid phase zone 46 through the liquid flow pipe 7.

[0029] Preferably, the connection position between the airflow pipe 6 and the inlet pipe gas phase zone 22 and the gas phase buffer zone is set close to the upper end of the mist collector 5, and the connection position between the airflow pipe 6 and the liquid phase buffer zone is set close to the lower end of the mist collector 5, which is conducive to the filtration of liquid in the gas and the smooth circulation of the gas.

[0030] In one embodiment, the floating seal 42 is a float seal assembly, which includes a positioning portion, a float and a sealing portion. The sealing portion is located above the float and is arranged toward the gas outlet 431. The float floats up and down by relying on the buoyancy of the liquid. When the liquid phase output is large and the gas volume is small, the liquid level rises, driving the float to float up, and the seal is engaged with the gas outlet 431 to close the gas outlet 431 to prevent the liquid phase from flowing out of the gas phase pipeline 43; when the liquid phase output is small, the float will fall with the liquid level, the seal will separate from the gas outlet 431, and the gas outlet 431 will change from a closed state to an open state, and the gas in the gas phase space will flow out along the gas outlet and enter the gas meter 8.

[0031] In one embodiment, the liquid phase pipeline 44 is also provided with a pressure regulator 103 for regulating the internal pressure of the liquid phase pipeline 44. Preferably, the pressure regulator 103 is arranged downstream of the liquid meter 9 to adjust the pressure of the liquid phase pipeline 44. According to the buoyancy of the on-site medium, the pressure difference after adjustment of the pressure regulator 103 can satisfy the correspondence between the gravity and buoyancy of the float ball itself, so as to realize the free up and down movement of the float ball assembly. When there is only natural gas but no liquid in the imported medium, the pressure regulator 103 is used to close the liquid phase pipeline 44 to prevent the gas from entering the mass meter.

[0032] In one embodiment, the gas in the outlet vertical pipe 4 is output from the gas phase pipeline 43, and the liquid in the outlet vertical pipe 4 is output from the liquid phase pipeline 44. The gas in the gas phase pipeline 43 and the liquid in the liquid phase pipeline 44 flow to the manifold for mixing and output, and are connected to the oil well equipment through the output port 102. An overpressure protector 104 is installed between the input port 101 and the output port 102. When the inlet pressure exceeds the outlet pressure by more than 0.2MPa, the overpressure protector 104 automatically opens to release the pressure and realize the protection function. Preferably, a one-way valve 105 is also provided on the manifold. The one-way valve 105 is used to prevent the medium in the manifold from flowing back when the pressure of the output port 102 is greater than the pressure of the input port 101.

[0033] When in use, the crude oil imported from the oil field first enters the inlet vertical pipe 2 through the cyclone inlet pipe 1 to realize the first step of gas-liquid separation. The separated gas passes through the mist collector 5 for filtration and then enters the gas phase zone 45 of the outlet pipe. The separated liquid flows downward and passes through the flow-breaking plate 21 to realize the second step of gas-liquid separation. The separated gas floats upward and enters the gas phase zone 45 of the outlet pipe after filtration. It flows to the two-phase buffer pipe 3 or the gas phase zone 45 of the outlet pipe through the gas flow pipe 6. The liquid continues to flow downward and flows to the two-phase buffer pipe 3 or the liquid phase zone 46 of the outlet pipe through the liquid flow pipe 7. Then, the liquid after the crude oil separation flows out through the liquid phase pipeline 44 connected to the liquid phase zone 46 of the outlet pipe and is measured by the liquid meter 9. The separated gas flows out through the gas phase pipeline 43 connected to the gas phase zone 45 of the outlet pipe and is measured by the gas meter 8.

[0034] The novel three-phase metering device for oil field wellhead provided by the utility model can effectively separate and output the gas phase and liquid phase in crude oil through the interconnected inlet vertical pipe and outlet vertical pipe, and the design of mist collector and floating seal. It has simple structure, high safety factor and low maintenance cost. The separation effect of gas phase and liquid phase in crude oil is further increased through the design of flow breaker and vortex preventer. The gas-liquid separation effect is increased through the design of two-phase buffer tube. The separated gas is subjected to multi-layer filtration to reduce the liquid content in the gas, which is beneficial to improve the accuracy of separation and metering of gas phase and liquid phase in crude oil.

[0035] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present invention, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A novel three-phase metering device for oil field wellhead, characterized in that: The invention comprises an inlet vertical pipe (2) and an outlet vertical pipe (4) which are connected to each other. A mist collector (5) is arranged inside the inlet vertical pipe (2). The mist collector (5) divides the inlet vertical pipe (2) into an inlet pipe gas phase region (22) and an inlet pipe liquid phase region (23). A floating seal (42) is arranged inside the outlet vertical pipe (4). The floating seal (42) divides the outlet vertical pipe (4) into an outlet pipe gas phase region (45) and an outlet pipe liquid phase region (46). The outlet pipe liquid phase region (46) is connected to the outlet pipe gas phase region (45). The liquid phase region (23) of the inlet pipe is connected via a liquid flow pipe (7), and the gas phase region (45) of the outlet pipe is connected to the gas phase region (22) of the inlet pipe via a gas flow pipe (6); the gas phase region (45) of the outlet pipe is connected to a gas phase pipeline (43) for gas output, and a gas meter (8) is connected to the gas phase pipeline (43); the liquid phase region (46) of the outlet pipe is connected to a liquid phase pipeline (44) for liquid output, and a liquid meter (9) is connected to the liquid phase pipeline (44).

2. A novel three-phase metering device for oilfield wellhead according to claim 1, characterized in that: The inlet pipe liquid phase region (23) is provided with a flow-breaking plate (21), and the flow-breaking plate (21) is located above the connection end between the liquid flow pipe (7) and the outlet pipe liquid phase region (46).

3. A novel three-phase metering device for oilfield wellhead according to claim 1, characterized in that: The outlet pipe liquid phase region (46) is provided with a vortex breaker (41), and the vortex breaker (41) is located above the connection position between the liquid phase pipeline (44) and the outlet pipe liquid phase region (46).

4. A novel three-phase metering device for oilfield wellhead according to claim 1, characterized in that: A two-phase buffer tube (3) is also provided between the outlet vertical tube (4) and the inlet vertical tube (2). A mist collector (5) is provided inside the two-phase buffer tube (3). The mist collector (5) divides the two-phase buffer tube (3) into a gas phase buffer zone and a liquid phase buffer zone. The gas phase buffer zone is connected to the gas phase zone (45) of the outlet tube via a gas flow tube (6), and the liquid phase buffer zone is connected to the liquid phase zone (46) of the outlet tube via a liquid flow tube (7).

5. A novel three-phase metering device for oil field wellhead according to claim 1, characterized in that: A plurality of two-phase buffer tubes (3) are further provided between the outlet vertical tube (4) and the inlet vertical tube (2), each of the two-phase buffer tubes (3) being provided with a mist collector (5), the mist collector (5) dividing the two-phase buffer tube (3) into a gas phase buffer zone and a liquid phase buffer zone, the liquid phase buffer zones between the plurality of two-phase buffer tubes (3) being connected in sequence through a liquid flow tube (7), and the gas phase buffer zones between the plurality of two-phase buffer tubes (3) being connected in sequence with adjacent liquid phase buffer zones through an air flow tube (6).

6. A novel three-phase metering device for oil field wellhead according to claim 5, characterized in that: The connection position between the airflow pipe (6) and the gas phase zone (22) of the inlet pipe and the gas phase buffer zone is arranged near the upper end of the mist collector (5), and the connection position between the airflow pipe (6) and the liquid phase buffer zone is arranged near the lower end of the mist collector (5).

7. A novel three-phase metering device for oil field wellhead according to claim 1, characterized in that: The liquid phase pipeline (44) is provided with a pressure regulator (103), which is arranged downstream of the liquid meter (9) and is used to adjust the pressure of the liquid phase pipeline (44) or close the liquid phase pipeline (44).

8. A novel three-phase metering device for oil field wellhead according to claim 1, characterized in that: The invention comprises a swirl inlet pipe (1), wherein the swirl inlet pipe (1) comprises a vertical pipe (11) and an inclined pipe (12), wherein the lower end of the vertical pipe (11) is connected to an input port (101), the upper end of the vertical pipe (11) is connected to the inclined pipe (12), and the horizontal lower end of the inclined pipe (12) is connected to the side wall of the inlet vertical pipe (2) and is connected to the inlet vertical pipe (2).

9. A novel three-phase metering device for oil field wellhead according to claim 8, characterized in that: It comprises a one-way valve (105), the output ends of the liquid phase pipeline (44) and the gas phase pipeline (43) are connected to one end of a manifold, the other end of the manifold is connected to the output port (102), and the one-way valve (105) is connected to the manifold.

10. A novel three-phase metering device for oil field wellhead according to claim 9, characterized in that: It comprises an overpressure protector (104), wherein the overpressure protector (104) is arranged in communication between the input port (101) and the output port (102).

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