Plug flow dissipation separation device and liquid plug dissipation effect test system thereof

Abstract

The invention relates to a plug flow dissipation separation device and a liquid plug dissipation effect test system thereof.The plug flow dissipation separation device comprises a plurality of finger-shaped separation branch pipes, and each finger-shaped separation branch pipe comprises a finger-shaped inlet pipe, an upward-inclined pipe, a gas phase top pipe, an upward-inclined gas phase outlet pipe, a downward-inclined pipe, an expanding pipe, a liquid phase bottom pipe, a downward-inclined liquid phase outlet pipe and a vertical pipe, and the axes of the finger-shaped inlet pipe, the upward-inclined pipe, the gas phase top pipe, the upward-inclined gas phase outlet pipe, the downward-inclined pipe, the expanding pipe, the liquid phase bottom pipe and the downward-inclined liquid phase outlet pipe are located in the same positioning plane; the finger-shaped inlet pipe extends along a straight line, pipe inlets of the upper inclined pipe and the lower inclined pipe are connected with a pipe outlet of the finger-shaped inlet pipe and obliquely extend upwards and downwards respectively, the gas-phase jacking pipe is connected with the upper inclined pipe, the gas-phase jacking pipe linearly extends and is parallel to the finger-shaped inlet pipe, and the upper inclined gas-phase outlet pipe is connected with the gas-phase jacking pipe and obliquely extends upwards. The expanding pipe is connected with the declining pipe, the liquid-phase bottom pipe is connected with the expanding pipe and is parallel to the gas-phase top pipe, the declining liquid-phase outlet pipe is connected with the liquid-phase bottom pipe and obliquely extends downwards, and the two ends of the vertical pipe are connected with the gas-phase top pipe and the liquid-phase bottom pipe respectively.

Description

Technical Field

[0001] The present invention relates to the technical field of multiphase separation of oil and gas gathering and transportation systems, and in particular to a plug flow dissipation separation device and a liquid plug dissipation effect test system thereof. Background Art

[0002] During the development and production of deepwater condensate gas fields, condensate is continuously generated. This condensate accumulates in low-lying areas of pipelines, deteriorating flow conditions. Using multiphase boosting technology to transport wellbore fluids ashore presents drawbacks such as low boosting efficiency and poor reliability. Furthermore, the multiphase mixed transport process is prone to flow safety issues such as severe slugging and hydrate blockage. However, the technique of underwater gas-liquid separation followed by single-phase boosting not only reduces wellhead backpressure, lowers lifting energy consumption, and improves recovery, but also effectively avoids flow safety issues. This is of great significance for ensuring the safe development of deepwater gas fields and improving economic efficiency.

[0003] Currently, underwater separation technologies can be divided into: tubular separation technology, gravity separation technology, caisson separation technology, and internal tube separation technology. Caisson separation technology involves numerous devices and is complex to control; internal tube separation technology has a narrow operating range; and volumetric separators based on gravity separation technology are limited by the high external pressure in deep water, requiring the wall thickness of the separation tank to be very thick, resulting in increased weight and installation difficulty. Tubular separation technology, on the other hand, utilizes a slender tubular structure to withstand high external pressure with a smaller wall thickness, reducing the weight of the separation device, making installation easier, and saving investment and development. Furthermore, through reasonable combination, it can meet the requirements of compactness and efficiency, making it ideally suited for deepwater, high-pressure environments.

[0004] Patent application number CN200680008192.4 discloses a tubular separator inlet device with multiple vertically extending degassing tubes terminating in an upward-sloping gas collection pipe. The inlet device terminates in an expanded, downward-sloping delivery pipe, allowing the gas phase to be collected in the gas collection pipe while the liquid phase remains in the delivery pipe. This patent describes only a single separator inlet device, lacking structural components for efficiently handling slug flows and limiting its processing capacity. Patent application number CN200680015023.3 discloses a tubular separator that utilizes a slightly tiltable, large-diameter, long-length curved tubular structure for multiphase flow separation. However, this solution primarily relies on residence time for separation, resulting in a limited functionality and a less compact structure. The utility model patent application number CN 201420080288.3 discloses a deep-sea underwater multi-tube horizontal gas-liquid separator. The separator has multiple sets of single tubes arranged in parallel on the inlet pipe, and each single tube is equipped with a flow guide. The multiphase flow is separated by cyclonic flow due to density difference. The multiphase flow pressure loss in this patent is large, and the incoming flow received by each single tube is unequal, making the overall separation process unstable.

[0005] Therefore, how to make the tubular structure compact, have high separation efficiency, strong impact resistance and low cost is an urgent problem to be solved in underwater separation technology. Summary of the Invention

[0006] In view of the above-mentioned shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a plug flow dissipation separation device and a liquid plug dissipation effect test system thereof, which has a compact tubular structure, high separation efficiency, strong impact resistance and low cost.

[0007] To achieve the above-mentioned object, the present invention provides a plug flow dissipation separation device, comprising a plurality of finger-shaped separation branches, wherein the finger-shaped separation branches include a finger-shaped inlet pipe, an upward-inclined pipe, a gas phase top pipe, an upward-inclined gas phase outlet pipe, a downward-inclined pipe, an expanded diameter pipe, a liquid phase bottom pipe, a downward-inclined liquid phase outlet pipe and a vertical pipe, all of whose axes are located in the same positioning plane, wherein the finger-shaped inlet pipe extends in a straight line, the inlets of the upward-inclined pipe and the downward-inclined pipe are connected to the outlet of the finger-shaped inlet pipe and extend upward and downward, respectively, and the inlet of the gas phase top pipe is connected to the inlet of the upward-inclined pipe and the downward-inclined pipe. The outlet of the inclined pipe is connected, the gas phase top pipe extends straightly and is parallel to the finger-shaped inlet pipe, the inlet of the upward-inclined gas phase outlet pipe is connected to the outlet of the gas phase top pipe and extends obliquely upward, the inlet of the expanded pipe is connected to the outlet of the downward-inclined pipe, the inlet of the liquid phase bottom pipe is connected to the outlet of the expanded pipe, and the liquid phase bottom pipe is parallel to the gas phase top pipe, the inlet of the downward-inclined liquid phase outlet pipe is connected to the outlet of the liquid phase bottom pipe, and extends obliquely downward, and the two ends of the riser are respectively connected to the gas phase top pipe and the liquid phase bottom pipe.

[0008] Furthermore, it also includes a gas collecting manifold and a liquid collecting manifold, wherein the gas collecting manifold is connected to the outlets of the upward gas phase outlet pipes of all the finger-shaped separation branch pipes, and the liquid collecting manifold is connected to the outlets of the downward liquid phase outlet pipes of all the finger-shaped separation branch pipes.

[0009] Furthermore, the vertical pipe in the finger-shaped separation branch pipe is perpendicular to the gas phase top pipe.

[0010] Furthermore, the angle between the axis of the downward-inclined pipe and the axis of the finger-shaped separation branch pipe is 40-50°, and the axis of the upward-inclined pipe is perpendicular to the axis of the downward-inclined pipe.

[0011] Furthermore, the inner hole of the expanded tube is conical, and the angle between the conical surface and the axis is 30 to 60 degrees.

[0012] Furthermore, it also includes a diverter pipe mechanism, which has a diverter inlet pipe and multiple diverter outlets, and each diverter outlet is respectively connected to a finger-shaped inlet pipe of a finger-shaped separation branch pipe.

[0013] Furthermore, the diverter pipe mechanism includes a plurality of diverter unit pipes, each of the diverter unit pipes includes a unit inlet pipe and a diverter manifold, the diverter manifold is provided with a plurality of unit outlets, the unit inlet pipe is perpendicular to the diverter manifold, the diverter pipe mechanism includes a multi-stage diverter pipe group, the first-stage diverter pipe group includes a diverter unit pipe, and the unit inlet pipe of the diverter unit pipe is the diverter inlet pipe of the diverter pipe mechanism, the subsequent diverter pipe groups include a plurality of diverter unit pipes, the unit outlets of the diverter unit pipes in the upper-stage diverter pipe group are connected to the unit inlet pipe of a diverter unit pipe in the lower-stage diverter pipe group, and the outlet of the unit outlet of the diverter unit pipe of the last-stage diverter pipe group constitutes a diverter unit outlet.

[0014] Furthermore, there are two unit outlets on the diversion manifold, and the two unit outlets are the same in size. The unit inlet pipe is located in the middle of the two unit outlets in the axial direction of the diversion manifold.

[0015] Furthermore, the diameter of the diversion manifold is larger than the diameter of the unit inlet pipe.

[0016] The present invention also provides a liquid plug dissipation effect testing system for the above-mentioned plug flow dissipation separation device, which is characterized by comprising a detection device, a data acquisition device and a data processing device, wherein the detection device includes a plurality of double-parallel conductivity probes, two parallel double-parallel conductivity probes are provided on the diversion inlet pipe of the diversion pipe mechanism, two parallel double-parallel conductivity probes are provided on the finger-shaped inlet pipe of the finger-shaped separation branch pipe, four parallel double-parallel conductivity probes are provided in sequence from upstream to downstream on the pipe section located on the upstream side of the riser of the liquid phase bottom pipe, and a double-parallel conductivity probe is provided on the pipe section located on the upstream side of the riser of the gas phase top pipe, wherein the double-parallel conductivity probes can detect the slug flow situation in the pipe and output a liquid plug electrical signal; the data acquisition device is connected to the double-parallel conductivity probes and can collect the detection signals of the double-parallel conductivity probes; the data processing device is connected to the data acquisition device and can perform calculation and processing on the detection signals.

[0017] As described above, the present invention relates to a plug flow dissipation separation device and a liquid plug dissipation effect test system thereof.

[0018] 1. Liquid plug dissipation stratification and gas-liquid separation are completed in the finger-shaped separation branch. Its tubular structure can withstand the high external pressure of deep water, and at the same time has high separation efficiency and good impact resistance. It can improve the separation efficiency by reducing the droplet settling distance, shortening the settling time, and increasing the total flow cross-sectional area to reduce the flow rate and increase the residence time. The tubular structure of the entire plug flow dissipation separation device is compact, with high separation efficiency, strong impact resistance and low cost.

[0019] 2. Diversion is carried out through the diversion pipe mechanism. The track is combined by forming a multi-stage diversion with multiple diversion unit pipes, which can achieve equal distribution and good diversion effect. After diversion, liquid plug dissipation stratification and gas-liquid separation are carried out through multiple finger-shaped separation branches. The liquid plug diversion, dissipation and separation process are completely spontaneous, and the operation and control are simple.

[0020] 3. The liquid plug dissipation effect test system can stably, accurately and sensitively obtain the liquid plug parameters in the slug flow dissipation process, and can be used to evaluate the separation effect of the slug flow dissipation separation device. It has the advantages of stable signal, high measurement accuracy and high resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the plug flow dissipation separation device of the present invention.

[0022] Figure 2 It is a structural schematic diagram of the finger-shaped separation branch pipe in the present invention.

[0023] Figure 3 Schematic diagram of the structure of the diverter pipe mechanism in the present invention.

[0024] Figure 4 Schematic diagram of the installation of dual parallel conductivity probes on the shunt tube mechanism of the present invention.

[0025] Figure 5 Schematic diagram of the installation of dual parallel conductivity probes on the finger-shaped separation branch pipe in the present invention.

[0026] Explanation of Figure Numbers

[0027] 1. Shunt pipe mechanism

[0028] 11. Diversion unit tube

[0029] 111 unit inlet pipe

[0030] 112 manifold

[0031] Unit 113 Exit

[0032] 2 finger-shaped separation branches

[0033] 21 Finger inlet pipe

[0034] 22 Upward tilt tube

[0035] 23 Gas-phase pipe jacking

[0036] 24 Upward-inclined gas phase outlet pipe

[0037] 25 Downward tilt pipe

[0038] 26 Expanded diameter pipe

[0039] 27 Liquid phase bottom tube

[0040] 28 Downward-inclined liquid phase outlet pipe

[0041] 29 riser

[0042] 3 Gas gathering manifold

[0043] 4 Liquid collecting manifold DETAILED DESCRIPTION

[0044] The following describes the implementation of the present invention through specific embodiments. People skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0045] It should be noted that the structures, proportions, sizes, etc. depicted in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions for the implementation of the present invention. Therefore, they have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the efficacy and purpose of the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle", etc. quoted in this specification are only for the convenience of description and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0046] See also Figures 1 to 5The present invention provides a plug flow dissipation separation device, comprising a plurality of finger-shaped separation branches 2, the finger-shaped separation branch 2 comprising a finger-shaped inlet pipe 21, an upward-inclined pipe 22, a gas phase top pipe 23, an upward-inclined gas phase outlet pipe 24, a downward-inclined pipe 25, an expanded diameter pipe 26, a liquid phase bottom pipe 27, a downward-inclined liquid phase outlet pipe 28 and a vertical pipe 29, all of which have axes located in the same positioning plane. The finger-shaped inlet pipe 21 extends in a straight line, and its inlet is used for two-phase flow to enter. The inlets of the upward-inclined pipe 22 and the downward-inclined pipe 25 are both connected to the outlet of the finger-shaped inlet pipe 21, and extend obliquely upward and downward, respectively, that is, the finger-shaped inlet pipe 21, the upward-inclined pipe 22 and the downward-inclined pipe 25 form a Y-shaped Pipe structure, the inlet of the gas phase top pipe 23 is connected to the outlet of the upward inclined pipe 22, the gas phase top pipe 23 extends straight and is parallel to the finger-shaped inlet pipe 21, the inlet of the upward inclined gas phase outlet pipe 24 is connected to the outlet of the gas phase top pipe 23 and extends upward obliquely, the inlet of the expanded pipe 26 is connected to the outlet of the downward inclined pipe 25, the inlet of the liquid phase bottom pipe 27 is connected to the outlet of the expanded pipe 26, the liquid phase bottom pipe 27 is parallel to the gas phase top pipe 23 and also extends straight, the inlet of the downward inclined liquid phase outlet pipe 28 is connected to the outlet of the liquid phase bottom pipe 27 and extends downward obliquely, and the two ends of the riser 29 are respectively connected to the gas phase top pipe 23 and the liquid phase bottom pipe 27. Preferably, the upward-inclined pipe 22 , the upward-inclined gas phase outlet pipe 24 , the downward-inclined pipe 25 , the expanded-diameter pipe 26 , the downward-inclined liquid phase outlet pipe 28 and the vertical pipe 29 in the finger-shaped separation branch pipe 2 are also straight pipes extending in a straight line.

[0047] The basic operating principle of the plug flow dissipation separation device disclosed herein is as follows: during operation, the positioning plane of the finger-shaped separation branch pipe 2 is vertical. When multiple finger-shaped separation branch pipes 2 are provided, their positioning planes are parallel. Most of the two-phase flow entering the finger-shaped inlet pipe 21 enters the down-inclined pipe 25, with a small portion entering the up-inclined pipe 22. This reduces the workload of the down-inclined pipe 25 in dissipating the stratified two-phase flow. A small amount of the two-phase flow passes through the up-inclined pipe 22 and enters the gas phase top pipe 23, where stratification is completed. The stratified liquid phase then falls from the riser 29 into the liquid phase bottom pipe 27. The stratified gas phase then exits the finger-shaped separation branch pipe 2 through the up-inclined gas phase outlet pipe 24. A large amount of two-phase flow dissipates and stratifies in the down-inclined pipe 25, and then enters the liquid phase bottom pipe 27 through the expanded diameter pipe 26. The two-phase flow velocity slows down, and the droplet residence time increases. At the same time, the droplets are prone to collide with the wall and deposit at the expanded diameter pipe 26. The liquid phase bottom pipe 27 will continue to dissipate the incompletely stratified liquid plug and make the droplets settle. The stratified gas phase rises to the gas phase top pipe 23 through the riser 29 in the liquid phase bottom pipe 27. The stratified liquid phase enters the down-inclined liquid phase outlet pipe 28 from the liquid phase bottom pipe 27 and then discharges from the finger-shaped separation branch 2. At the same time, the down-inclined liquid phase outlet pipe 28 acts as a liquid seal, reducing the entry of the gas phase and improving the quality of the separated liquid phase. In addition, at any elbow, tee, or expanded diameter of the finger-shaped separation branch 2, the droplets can collide and deposit with the separator wall, achieving a dissipative separation effect. The number of finger-shaped separation branches 2 can be set as needed. By increasing or decreasing the number, the separation efficiency can be flexibly adjusted, making it flexible and convenient to use. The plug flow dissipative separation device of the present invention has a simple structure and can well divert two-phase flow through a plurality of finger-shaped separation branches 2 . It has high separation efficiency, strong impact resistance and low cost.

[0048] In this embodiment, see Figure 1 、 Figure 2 and Figure 3 As a preferred design, the plug flow dissipative separation device further includes a gas collecting manifold 3 and a liquid collecting manifold 4. The gas collecting manifold 3 is connected to the outlets of the upward-inclined gas phase outlet pipes 24 of all the finger-shaped separation branch pipes 2, and the gas collecting manifold 3 is preferably perpendicular to all the upward-inclined gas phase outlet pipes 24. The liquid collecting manifold 4 is connected to the outlets of the downward-inclined liquid phase outlet pipes 28 of all the finger-shaped separation branch pipes 2, and the gas collecting manifold 3 is preferably perpendicular to all the downward-inclined liquid phase outlet pipes 28. The gas phases exiting the upward-inclined gas phase outlet pipes 24 of all the finger-shaped separation branch pipes 2 enter the gas collecting manifold 3 and are collectively sent out. At the same time, the liquid phases exiting the downward-inclined liquid phase outlet pipes 28 enter the liquid collecting manifold 4 and are collectively sent out.

[0049] In the present invention, the function of the down-dip pipe 25 is to dissipate stratified two-phase flow. The specific diameter of the down-dip pipe 25 can be determined by combining the Taitel-Dukler flow pattern transition criterion equation with the stratified flow hydrodynamic characteristic equation, and then assuming a dimensionless liquid film height and solving it through an iterative method. To ensure the liquid plug dissipation stratification effect, the inclination angle of the down-dip pipe 25 should be neither too small nor too large. Preferably, the axis of the up-dip pipe 22 is perpendicular to the axis of the down-dip pipe 25, and the angle between the axis of the down-dip pipe 25 and the axis of the finger-shaped separation branch pipe 2 is 40° to 50°, with 45° being preferred. This ensures that at least 20% of the gas phase of the two-phase flow entering the finger-shaped branch pipe can enter the gas phase top pipe 23 through this angle.

[0050] See also Figure 1 and Figure 3 The inner diameter of the expanding tube 26 gradually increases from the inlet to the outlet. As a preferred design, in this embodiment, the inner diameter of the expanding tube 26 is a conical surface, and the angle between the conical surface and the axis is 30° to 60°.

[0051] In the present invention, liquid bottom pipe 27 is used to continue dissipating incompletely stratified liquid plugs and allow droplets to settle. This ensures a low two-phase flow velocity and sufficient time for droplets to settle. As a preferred design, in this embodiment, the inner diameter of liquid bottom pipe 27 is 1.5 times that of downpipe 25. Expanding pipe 26 creates a jetting effect, allowing droplets to impact the wall and settle. The minimum length from the inlet of liquid bottom pipe 27 to the bottom end of riser 29 is determined by combining the formula for droplet settling velocity with the superficial gas velocity in liquid bottom pipe 27.

[0052] In this embodiment, see Figure 1 and Figure 2 As a preferred design, the riser 29 in the finger-shaped separation branch 2 is perpendicular to the gas phase top tube 23. Riser 29 serves as the passageway for the exchange between the liquid phase of gas phase top tube 23 and the gas phase of liquid phase bottom tube 27. The droplet settling velocity should be greater than the average gas velocity across the cross-section of riser 29. Therefore, the minimum diameter of riser 29 can be calculated by combining the formula for droplet settling velocity with the apparent gas velocity of riser 29. When riser 29 is not completely filled with liquid from liquid phase bottom tube 27, it is considered to be functioning properly. Therefore, the Bernoulli equation and the pressure transient equation for the arrival of a liquid slug can be used to calculate the maximum height that the liquid phase can reach in riser 29. This height is then used as the minimum height of riser 29.

[0053] The lengths of other components in the finger-shaped separation branch pipe 2 can be calculated based on actual conditions and geometric relationships.

[0054] In this embodiment, see Figure 1 and Figure 3As a preferred design, the plug flow dissipation separation device further includes a diverter pipe mechanism 1 having a diverter inlet pipe and multiple diverter outlets, each of which is connected to a finger-shaped inlet pipe 21 of a finger-shaped separation branch pipe 2. The two-phase flow from the incoming flow pipeline enters the diverter inlet pipe of the diverter pipe mechanism 1, is divided, and has a reduced velocity and momentum. It then flows out of the multiple diverter outlets and enters the multiple finger-shaped separation branches 2.

[0055] In this embodiment, see Figure 1 and Figure 3 As a preferred design, the diverter pipe mechanism 1 includes a plurality of diverter unit pipes 11, each of the diverter unit pipes 11 includes a unit inlet pipe 111 and a diverter manifold 112, and a plurality of unit outlets 113 are provided on the diverter manifold 112. The unit inlet pipe 111 is perpendicular to the diverter manifold 112, and the diverter pipe mechanism 1 includes a two-stage diverter pipe group. The first-stage diverter pipe group includes a diverter unit pipe 11, and the unit inlet pipe 111 of the diverter unit pipe 11 is the diverter inlet pipe of the diverter pipe mechanism 1, and the second-stage diverter pipe group includes two diverter unit pipes 11, which can also be other numbers. The unit outlet 113 of the diverter unit pipe 11 in the first-stage diverter pipe group is connected to the unit inlet pipe 111 of a diverter unit pipe 11 in the second-stage diverter pipe group. At this time, the outlet of the unit outlet 113 of the diverter unit pipe 11 of the second-stage diverter pipe group constitutes the diverter outlet of the diverter pipe mechanism 1, which is used to be connected to the finger-shaped separation branch pipe 2. In other embodiments, when the separation device has a large processing capacity, three or more levels of diverter tube groups may be added, and the unit outlet 113 of each diverter unit tube 11 in the second-level diverter tube group is connected to a unit outlet 113, thereby obtaining a third-level diverter tube group. When more levels of diverter tube groups are added, the unit outlet 113 of the diverter unit tube 11 of the last-level diverter tube group constitutes the diverter outlet of the diverter tube mechanism 1. Preferably, the unit inlet pipes 111 of the diverter unit tubes 11 in the same-level diverter tube group are all parallel, and the unit inlet pipes 111 of the diverter unit tubes 11 in different-level diverter tube groups are also all parallel.

[0056] In this embodiment, see Figure 1 and Figure 3, further preferably, there are two unit outlets 113 in the diversion unit pipe 11, and the two unit outlets 113 are of the same size, and the unit inlet pipe 111 is located in the middle of the two unit outlets 113 in the axial direction of the diversion manifold 112, and the two-phase flow can be evenly divided by a single diversion unit pipe 11. The diversion unit pipes 11 in the diversion pipe group of the same level have the same structure, and the diversion pipe mechanism 1 is combined into a multi-stage diversion by the diversion unit pipes 11 that can perform even division, which is conducive to the efficient and stable operation of the finger-shaped slug flow dissipation separation device. Furthermore, the inner diameter of the unit inlet pipe 111 in the diversion unit pipe 11 is consistent with the inner diameter of the two-phase incoming flow pipe to avoid unnecessary acceleration. The inner diameter of the diversion manifold 112 is larger than the inner diameter of the unit inlet pipe 111, which can divide the incoming flow as evenly as possible.

[0057] In this embodiment, see Figure 1 Further preferably, when the diverter pipe mechanism 1 is connected to the finger-shaped separation branch pipe 2, the unit inlet pipe 111 and the unit outlet 113 of the diverter unit pipe 11 remain parallel to the finger-shaped inlet pipe 21, the liquid phase bottom pipe 27 and the gas phase top pipe 23 of the finger-shaped separation branch pipe 2.

[0058] When the plug flow dissipation separation device is in use, it is preferably set with a slope of 1% to 3% as a whole, and its downstream side is lower than the upstream side. That is, at this time, the liquid phase bottom pipe 27 and the gas phase top pipe 23 in the finger-shaped separation branch pipe 2, as well as the unit inlet pipe 111 in the diverter pipe mechanism 1, are all set with a slope of 1% to 3%, so as to better achieve slug flow dissipation.

[0059] The plug flow dissipative separation device of the present invention can be used in the multiphase mixed transportation process in the development and production of deep-water gas fields, and can ensure the safe development of deep-water gas fields and improve economic benefits.

[0060] The present invention also provides a liquid plug dissipation effect test system of the above-mentioned plug flow dissipation separation device, including a detection device, a data acquisition device and a data processing device. The detection device includes a plurality of double parallel conductivity probes. The diversion inlet pipe of the diversion pipe mechanism 1 is provided with two parallel double parallel conductivity probes. Figure 4 , respectively denoted as CP1 and CP2, with an appropriate distance between CP1 and CP2, and the two constitute a probe group. The finger-shaped inlet pipe 21 of the finger-shaped separation branch pipe 2 is provided with two parallel double-parallel conductivity probes, see Figure 5, respectively designated CP3 and CP4. CP3 and CP4 are appropriately spaced apart, forming a probe group. Liquid phase bottom pipe 27 has four parallel dual-parallel conductivity probes installed in sequence from upstream to downstream on the upstream side of riser 29. These probes are designated CP5, CP6, CP7, and CP8. CP5 and CP6 are appropriately spaced apart, forming a probe group used to measure the upstream section of liquid phase bottom pipe 27. CP7 and CP8 are appropriately spaced apart, forming a probe group used to measure the downstream section of liquid phase bottom pipe 27. Gas phase top pipe 23 has a dual-parallel conductivity probe designated CP9 on the upstream side of riser 29. The dual-parallel conductivity probes can detect slug flow within the pipe and output electrical signals indicating liquid slug. A data acquisition device is connected to the dual-parallel conductivity probes to collect their detection signals. A data processing device is also connected to the data acquisition device to perform computational processing on the detection signals.

[0061] In the present invention, the dual parallel conductivity probe is an existing detection instrument, comprising two parallel conductive metal wire electrodes in direct contact with the fluid and a probe signal processing circuit module. The diameter of the metal wire electrodes cannot be too small to avoid affecting the accuracy of the liquid film resistance test, nor can it be too large to avoid interfering with the fluid flow. The spacing between the metal wire electrodes cannot be too small to cause mutual interference, nor can it be too large to cause a decrease in the accuracy of the liquid film test. Therefore, preferably, the metal wire electrodes are made of nickel-chromium alloy wire, which is soft and elastic, with a diameter of 0.3mm and a spacing of 5mm. It is not easy to permanently deform under fluid impact, has little interference with the flow, and ensures the accuracy of the liquid film test. The probe signal processing circuit module mainly includes a sinusoidal excitation voltage generation circuit, a signal follower circuit, a current-voltage conversion circuit, a full-wave rectifier circuit, a second-order low-pass filter circuit, and a signal amplification circuit. The sinusoidal excitation voltage generating circuit generates a sinusoidal signal with a certain frequency and peak value, which then enters the signal following circuit to ensure that the excitation signal is not deformed and to filter out low-frequency noise in the signal; after that, the carrier current signal carrying the physical signal is converted into a stable voltage signal in the current-voltage conversion circuit; in the standard full-wave rectifier circuit, the voltage signal uses the unidirectional conductivity of the diode to convert the alternating current into unidirectional pulsed direct current; finally, the direct current signal is amplified by the amplifier circuit to ensure that the external output circuit does not affect the probe adjustment circuit.

[0062] In this embodiment, the data acquisition device consists of two components: a high-speed acquisition card for the dual-row conductivity probe electrical signals and a data acquisition program front panel. Specifically, the high-speed acquisition card can be a National Instruments PCI-6225 high-speed acquisition card, which offers 16-bit resolution, 32 analog input channels, and 48 digital input / output ports, ensuring measurement accuracy, resolution, and sensitivity. The data acquisition program front panel can be implemented using LABVIEW software. Signals collected by the high-speed acquisition card are quickly and efficiently stored in binary format, eliminating redundant data and facilitating subsequent data analysis.

[0063] In this embodiment, the data processing device is provided with a data processing program compiled using Labview software to process the data collected by the above-mentioned data acquisition device. In addition to conventional functions such as acquisition, control, filtering and statistics, the data processing device also has functions such as joint time-frequency analysis, wavelet analysis and filter design. Based on the above-mentioned data processing device, the liquid holdup signals of various liquid plugs can be obtained, and cross-correlation operations can be performed based on the signals of each probe group to obtain various liquid plug parameters. Specifically, the liquid holdup of the liquid plug is calculated based on the liquid film resistance between the dual parallel conductivity probes. The liquid plug speed is calculated based on the distance between the two dual parallel conductivity probes in each probe group, and the time difference between the signals of the liquid plug passing through the two dual parallel conductivity probes in succession. The liquid plug length can be calculated based on the duration of the signal of the liquid plug passing through the two dual parallel conductivity probes in the probe group, and the above-mentioned liquid plug speed.

[0064] The slug dissipation effect test system performs tests while the slug flow dissipation separation device is operating. Dual parallel conductivity probes CP1 and CP2 collect the slug flow electrical signal from the shunt inlet pipe. Dual parallel conductivity probes CP3 and CP4 collect the slug flow electrical signal from the finger-shaped inlet pipe 21. Dual parallel conductivity probes CP5, CP6, CP7, and CP8 collect the slug flow electrical signal from the liquid phase bottom pipe 27. The data acquisition and processing devices described above determine parameters such as the holdup, velocity, and length of the slugs in the corresponding pipes. Dual parallel conductivity probe CP9 collects the slug flow electrical signal from the gas phase top pipe 23. The data acquisition and processing devices described above determine the holdup. These parameters obtained through testing can be used to evaluate the separation effect of the slug flow dissipation separation device and can further guide the design of high-performance slug flow dissipation separation devices.

[0065] From the above, it can be seen that the plug flow dissipation separation device and the liquid plug dissipation effect test system of the present invention

[0066] 1. Liquid plug dissipation stratification and gas-liquid separation are completed through the finger-shaped separation branch 2. Its tubular structure can withstand the high external pressure of deep water, and at the same time has high separation efficiency and good impact resistance. It can improve the separation efficiency by reducing the droplet settling distance, shortening the settling time, and increasing the total flow cross-sectional area to reduce the flow rate and increase the residence time. The tubular structure of the entire plug flow dissipation separation device is compact, with high separation efficiency, strong impact resistance and low cost.

[0067] 2. Diversion is carried out through the diversion pipe mechanism 1, and the track is merged through a multi-stage diversion composed of multiple diversion unit pipes 11, which can achieve equal distribution and good diversion effect. After diversion, liquid plug dissipation stratification and gas-liquid separation are carried out through multiple finger-shaped separation branches 2. The liquid plug diversion, dissipation and separation process are completely spontaneous, and the operation and control are simple.

[0068] 3. The liquid plug dissipation effect test system can stably, accurately and sensitively obtain the liquid plug parameters in the slug flow dissipation process, and can be used to evaluate the separation effect of the slug flow dissipation separation device. It has the advantages of stable signal, high measurement accuracy and high resolution.

[0069] In summary, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

[0070] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A plug flow dissipation separation device, characterized in that: The invention comprises a plurality of finger-shaped separation branch pipes (2), wherein the finger-shaped separation branch pipes (2) comprise a finger-shaped inlet pipe (21), an upward-inclined pipe (22), a gas phase top pipe (23), an upward-inclined gas phase outlet pipe (24), a downward-inclined pipe (25), an expanded diameter pipe (26), a liquid phase bottom pipe (27), a downward-inclined liquid phase outlet pipe (28) and a vertical pipe (29), the axes of which are all located in the same positioning plane. The finger-shaped inlet pipe (21) extends in a straight line. The inlets of the upward-inclined pipe (22) and the downward-inclined pipe (25) are both connected to the outlet of the finger-shaped inlet pipe (21) and extend upward and downward, respectively. The inlet of the gas phase top pipe (23) is connected to the outlet of the upward-inclined pipe (22). The gas phase top pipe (23) extends in a straight line and is parallel to the finger-shaped inlet pipe (21); the pipe inlet of the upward-inclined gas phase outlet pipe (24) is connected to the pipe outlet of the gas phase top pipe (23) and extends upwardly in an inclined manner; the pipe inlet of the expanded pipe (26) is connected to the pipe outlet of the downward-inclined pipe (25); the pipe inlet of the liquid phase bottom pipe (27) is connected to the pipe outlet of the expanded pipe (26), and the liquid phase bottom pipe (27) is parallel to the gas phase top pipe (23); the pipe inlet of the downward-inclined liquid phase outlet pipe (28) is connected to the pipe outlet of the liquid phase bottom pipe (27) and extends downwardly in an inclined manner; and the two ends of the vertical pipe (29) are respectively connected to the gas phase top pipe (23) and the liquid phase bottom pipe (27).

2. The plug flow dissipation separation device according to claim 1, characterized in that: It also includes a gas collecting manifold (3) and a liquid collecting manifold (4), wherein the gas collecting manifold (3) is connected to the outlets of the upward-inclined gas phase outlet pipes (24) of all the finger-shaped separation branch pipes (2), and the liquid collecting manifold (4) is connected to the outlets of the downward-inclined liquid phase outlet pipes (28) of all the finger-shaped separation branch pipes (2).

3. The plug flow dissipation separation device according to claim 1, characterized in that: The vertical pipe (29) in the finger-shaped separation branch pipe (2) is perpendicular to the gas phase top pipe (23).

4. The plug flow dissipation separation device according to claim 1, characterized in that: The included angle between the axis of the downward-inclined pipe (25) and the axis of the finger-shaped separation branch pipe (2) is 40-50 degrees, and the axis of the upward-inclined pipe (22) is perpendicular to the axis of the downward-inclined pipe (25).

5. The plug flow dissipation separation device according to claim 1, characterized in that: The inner hole of the expanded tube (26) is conical, and the angle between the conical surface and the axis is 30-60 degrees.

6. The plug flow dissipation separation device according to claim 1, characterized in that: It also includes a diverter pipe mechanism (1), which has a diverter inlet pipe and multiple diverter outlets, and each diverter outlet is respectively connected to a finger-shaped inlet pipe (21) of a finger-shaped separation branch pipe (2).

7. The plug flow dissipation separation device according to claim 6, characterized in that: The diverter pipe mechanism (1) comprises a plurality of diverter unit pipes (11), each of the diverter unit pipes (11) comprises a unit inlet pipe (111) and a diverter manifold (112), the diverter manifold (112) is provided with a plurality of unit outlets (113), the unit inlet pipe (111) is perpendicular to the diverter manifold (112), the diverter pipe mechanism (1) comprises a multi-stage diverter pipe group, the first stage diverter pipe group comprises a diverter unit pipe (11), and the diverter unit pipe ( The unit inlet pipe (111) of the diverter pipe mechanism (1) is the diverter pipe of the diverter pipe mechanism (1). The diverter pipe group of the subsequent stage includes a plurality of diverter unit pipes (11). The unit outlets (113) of the diverter unit pipes (11) in the diverter pipe group of the previous stage are connected to the unit inlet pipe (111) of a diverter unit pipe (11) in the diverter pipe group of the next stage. The outlet of the unit outlet (113) of the diverter unit pipe (11) of the diverter pipe group of the last stage constitutes the diverter unit outlet (113).

8. The plug flow dissipation separation device according to claim 7, characterized in that: There are two unit outlets (113) on the diversion manifold (112), and the two unit outlets (113) are of the same size. The unit inlet pipe (111) is located in the middle of the two unit outlets (113) in the axial direction of the diversion manifold (112).

9. The plug flow dissipation separation device according to claim 7, characterized in that: The diameter of the diversion manifold (112) is larger than the diameter of the unit inlet pipe (111).

10. A system for testing the slug dissipation effect of a slug flow dissipation separation device according to claim 6, characterized in that: The invention comprises a detection device, a data acquisition device and a data processing device. The detection device comprises a plurality of double-parallel conductivity probes (5). Two parallel double-parallel conductivity probes (5) are provided on the diversion inlet pipe of the diversion pipe mechanism (1). Two parallel double-parallel conductivity probes (5) are provided on the finger-shaped inlet pipe (21) of the finger-shaped separation branch pipe (2). Four parallel double-parallel conductivity probes (5) are provided in sequence from upstream to downstream on the pipe section located on the upstream side of the vertical pipe (29) of the liquid phase bottom pipe (27). A double-parallel conductivity probe (5) is provided on the pipe section located on the upstream side of the vertical pipe (29) of the gas phase top pipe (23). The double-parallel conductivity probes (5) can detect the slug flow situation in the pipe and output a liquid slug electrical signal. The data acquisition device is connected to the double-parallel conductivity probes (5) and can acquire the detection signals of the double-parallel conductivity probes (5). The data processing device is connected to the data acquisition device and can perform calculation processing on the detection signals.

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