Search

CN-121994998-A - Device and method for measuring section content of gas-liquid two-phase flow pipeline

CN121994998ACN 121994998 ACN121994998 ACN 121994998ACN-121994998-A

Abstract

The invention discloses a device and a method for measuring the section content of a gas-liquid two-phase flow pipeline, which relate to the field of gas-liquid two-phase flow measurement, wherein the measuring device comprises a gas-liquid supply pipeline system, a gas-liquid flow detector and a gas-phase flow detector, wherein the gas-liquid supply pipeline system comprises a liquid storage tank, a gas-liquid separation tank, a water pump, a fan, a liquid-phase flow detector and a gas-phase flow detector are connected to the gas-liquid supply pipeline; the detection pipeline system is arranged to be capable of detecting the content of gas and liquid after circulating with the gas-liquid supply pipeline system. The method and the device can be used for accurately measuring the gas phase and liquid phase content of the section of the gas-liquid two-phase flow pipeline in real time, perfecting the virtual height correction function of the wet gas flowmeter to provide key parameters, improving the accuracy of the gas-liquid two-phase measurement result of the wet gas flowmeter, and achieving the aim that the testing device can provide real-time and accurate gas phase and liquid phase content in the testing process of obtaining the virtual height correction function for the wet gas flowmeter.

Inventors

  • LIU DINGFA
  • ZHANG QIANG
  • ZHOU LI
  • WANG HUI

Assignees

  • 中国石油天然气股份有限公司

Dates

Publication Date
20260508
Application Date
20241108

Claims (10)

  1. 1. The utility model provides a gas-liquid two-phase flow pipeline cross-section percentage by content measuring device which characterized in that includes: the gas-liquid supply pipeline system comprises a gas-liquid supply pipeline (1), wherein the gas-liquid supply pipeline (1) is connected with a liquid storage tank (2), a gas-liquid separation tank (3), a water pump (4) and a fan (5), a liquid phase flow detector (7) and a gas phase flow detector (8); a detection pipe system configured to be capable of detecting the contents of gas and liquid after circulating with the gas-liquid supply pipe system; The water pump (4) is used for driving the liquid in the liquid storage tank (2) and circularly flowing in a gas-liquid supply pipeline system and a detection pipeline system; The fan (5) is used for driving the gas in the gas-liquid separation tank (3) and then circularly flowing in a gas-liquid supply pipeline system and a detection pipeline system; the liquid phase flow detector (7) is used for detecting the liquid flow in the gas-liquid supply pipeline (1); The gas phase flow detector (8) is used for detecting the gas flow in the gas-liquid supply pipeline (1).
  2. 2. The gas-liquid two-phase flow pipeline section content measuring device according to claim 1, wherein the detection pipeline system comprises a straight pipe section (9), a test section (10), a first through valve (11) and a second through valve (12), the first through valve (11) comprises an A1 port, a B1 port and a C1 port which are communicated with each other, and the second through valve (12) comprises an A2 port, a B2 port and a C2 port which are communicated with each other; Two ends of the test section (10) are respectively communicated with the C1 port and the C2 port, two ends of the straight pipe section (9) are respectively communicated with the B1 port and the B2 port, the A2 port is communicated with the gas-liquid separation tank (3), and the A1 port is communicated with the gas-liquid supply pipeline (1); The first through valve (11) can respectively control the fluid circulation of the A1 port, the B1 port and the C1 port, and the second through valve (12) can respectively control the fluid circulation of the A2 port, the B2 port and the C2 port.
  3. 3. The device for measuring the section content of the gas-liquid two-phase flow pipeline according to claim 2, wherein the gas and the liquid separated by the gas-liquid separation tank (3) are discharged in opposite directions through the gas-liquid supply pipeline (1) and then are collected and mixed, and enter a detection pipeline system from an A1 port; The bottom of the gas-liquid separation tank (3) is communicated with the liquid storage tank (2), and liquid in the gas-liquid separation tank can be conveyed into the liquid storage tank (2); the top of the gas-liquid separation tank (3) is communicated with the input end of the fan (5), and the output end of the fan (5) is communicated with the input end of the gas phase flow detector (8); the output end of the liquid storage tank (2) is communicated with the input end of the water pump (4), and the output end of the water pump (4) is communicated with the input end of the liquid phase flow detector (7); the output end of the gas phase flow detector (8) is communicated with the output end of the liquid phase flow detector (7); The port A1 is communicated with a polymerization pipeline at the output end of the gas phase flow detector (8) and the output end of the liquid phase flow detector (7).
  4. 4. The device for measuring the cross-sectional content of the gas-liquid two-phase flow pipeline according to claim 2, wherein the flow cross-sectional area of the test section (10) is equal to the flow cross-sectional area of the straight pipe section (9), the length of the test section (10) is L 2 , and the length of the straight pipe section (9) is L 1 ; The length of the L 2 is larger than that of the L 1 , the length difference is L 3 , and the L 3 is larger than 0; The test section (10) is provided with a moisture flowmeter to be tested.
  5. 5. A method for measuring the section content of a gas-liquid two-phase flow pipeline, which is realized by the device of any one of claims 1 to 4, and is characterized by comprising the following steps: S1, flushing a gas medium with the pressure of P into a circulating pipeline, and injecting a liquid medium into a liquid storage tank, wherein the liquid level height is measured to be h 1 ; S2, adjusting a gas medium in a fan driving circulation pipeline to circularly flow, wherein the gas volume flow measured by a gas phase flow detector is Q g , adjusting a water pump to circularly flow a liquid medium in a liquid storage tank, the liquid volume flow measured by the liquid phase flow detector is Q l , connecting an A1 port with a B1 port, closing the connection between the A1 port and a C1 port, connecting the connection between the A2 port and the B2 port, closing the connection between the A2 port and the C2 port, mixing the gas medium and the liquid medium, flowing into a gas-liquid separation tank through a straight pipe section, separating the gas medium and the liquid medium by the gas-liquid separation tank, and flowing the gas medium into the fan from the upper end of the gas-liquid separation tank, and flowing the liquid medium into the liquid storage tank from the lower end of the gas-liquid separation tank when the liquid level reaches a certain height; S3, when the gas medium and the liquid medium of the circulating pipeline reach an equilibrium state, the liquid level in the liquid storage tank is kept to be h 3 , and the liquid level in the gas-liquid separation tank is kept to be h 2 ; S4, switching the communication between the A1 port and the C1 port of the first through valve, closing the communication between the A1 port and the B1 port, switching the communication between the A2 port and the C2 port of the second through valve, closing the communication between the A2 port and the B2 port, enabling a gas medium and a liquid medium to flow through the test section after being mixed, recording parameter data, and calculating the liquid phase section content F l and the gas phase section content F g of the test section.
  6. 6. The method for measuring the cross-sectional content of a gas-liquid two-phase flow pipeline according to claim 5, wherein the cross-sectional area of the inner cavity of the gas-liquid separation tank is S 1 , the cross-sectional area of the inner cavity of the liquid storage tank is S 2 , and the cross-sectional area of the inner cavity of the liquid storage tank is V 1 ＝h 1 S 2 -h 3 S 2 -h 2 S 1 .
  7. 7. The method for measuring the cross-sectional content of a gas-liquid two-phase flow pipeline according to claim 6, wherein the method further comprises the steps of turning off a water pump before the step S4, keeping a fan running, and returning all liquid media in the pipeline to the gas-liquid separation tank and the tank liquid storage tank along with the flow of the gas media; And S4, after the first through valve and the second through valve are switched, the fan and the water pump are regulated, so that the volume flow of the gas medium flowing through the test section is Q g , and the volume flow of the liquid medium is Q l .
  8. 8. The method for measuring the cross-sectional content of a gas-liquid two-phase flow pipeline according to claim 7, wherein when the flows of a gas medium and a liquid medium in all pipelines reach an equilibrium state, the liquid level in a liquid storage tank is kept to be h 4 , the liquid level in a gas-liquid separation tank is kept to be h 5 , and the volume of the liquid medium in all other pipelines except the liquid storage tank and the gas-liquid separation tank is V 2 , wherein V 2 ＝h 1 S 2 -h 4 S 2 -h 5 S 1 ; the sectional areas of the straight pipe section and the test section are S 3 , and in a pipeline with the length difference of the test section and the straight pipe section being L 3 , the volume of the liquid medium is V 3 ,V 3 ＝V 1 -V 2 ; liquid phase section content of test section Gas phase section content of test section
  9. 9. The method for measuring the cross-section content of the gas-liquid two-phase flow pipeline according to claim 6, wherein the step S4 comprises the steps of simultaneously switching flow directions by a first through valve and a second through valve, switching the first through valve to be communicated with an A1 port and a C1 port, closing an A1 port and a B1 port, switching the second through valve to be communicated with an A2 port and a C2 port, closing an A2 port and a B2 port, adjusting the volume flow of a gas medium to be Q g , adjusting the volume flow of a liquid medium to be Q l , and enabling the gas medium and the liquid medium to be mixed and flow through a test section.
  10. 10. The method for measuring the cross-sectional content of a gas-liquid two-phase flow pipeline according to claim 9, wherein when the flows of the gas medium and the liquid medium in all the pipelines reach an equilibrium state, the liquid level in the liquid storage tank is maintained at h 4 , the liquid level in the gas-liquid separation tank is maintained at h 5 , the total liquid volume in the liquid storage tank and the gas-liquid separation tank is further reduced, and the reduced volume is V 4 ; wherein the method comprises the steps of ,V 4 ＝(h 3 S 2 +h 2 S 1 )-(h 4 S 2 +h 5 S 1 ); Liquid phase section volume fraction of test section Gas phase cross-sectional volume fraction of test section

Description

Device and method for measuring section content of gas-liquid two-phase flow pipeline Technical Field The invention relates to the field of gas-liquid two-phase flow measurement, in particular to a device and a method for measuring the section content of a gas-liquid two-phase flow pipeline. Background The wet gas is a gas-liquid two-phase flow with gas phase as main and liquid phase as auxiliary, and the typical flow characteristic in the pipeline is that the gas phase pushes the liquid phase to flow in the pipeline. Because the gas-liquid two phases have larger difference in physical parameters such as density, viscosity, speed and the like, and speed slippage exists between the gas-liquid two phases, the flow of the gas-liquid two phases in the pipeline presents complex and changeable flow forms along with the change of flow parameters. The wet gas two-phase flow is commonly existing in the upstream field of the natural gas industry, and when the natural gas is extracted from a wellhead, a small amount of liquid is contained, so that the wet gas two-phase flow is typical in wet gas two-phase flow working conditions, and accurate metering of the wet gas two-phase flow produced by the wellhead is required in order to meet the understanding of geological information and the management of a natural gas extraction production system in the natural gas extraction process. At present, in the natural gas industry, a separation method is mainly adopted for measuring the wet gas and the two-phase flow, a separator is used for separating the gas-liquid two-phase flow into a gas phase and a liquid phase, a single-phase instrument is respectively adopted for measuring, the equipment is huge, the process flow is complex, the cost is high, special maintenance is required, and continuous online measurement cannot be realized. In recent years, some factories or research institutions develop corresponding wet gas flow meters for metering wet gas two-phase flow of a natural gas wellhead, the wet gas flow meters are basically based on traditional single-phase metering instruments for structural optimization design, and particularly the wet gas flow meters based on differential pressure type meters are widely applied, but when the differential pressure type meters are used for wet gas measurement, due to a small amount of liquid phase carried in a gas phase, a measurement result is larger than that when the differential pressure type meters do not contain the liquid phase, and the larger amplitude is called virtual height. The research shows that the virtual height characteristic of the differential pressure type wet gas flowmeter has good repeatability, so that the corresponding correction model can be adopted to correct the virtual height to obtain an accurate measurement result, however, the virtual height correction functions are all required to be realized based on a testing device capable of providing standard gas-liquid two-phase flow and combining parameters such as known gas phase or liquid phase content and the like, so that the virtual height correction function of the wet gas flowmeter is obtained through testing, and the gas-liquid two-phase content in a pipeline must be obtained simultaneously. Currently, when a wet gas flowmeter is used for testing, the gas phase and liquid phase contents in the section of a pipeline are usually estimated through measurement of the gas phase and liquid phase flowmeter before mixing, or are obtained through analysis processing in the modes of an electrical method, a ray method, a microwave method, an optical method, an ultrasonic method and the like, and the defects of high technical complexity, low accuracy, poor instantaneity, high use cost and the like generally exist in the modes, so that the field application is greatly limited. In view of this, the present application has been proposed. Disclosure of Invention The invention aims to provide a device and a method for measuring the section gas-liquid two-phase flow pipeline, which are used for improving the virtual height correction function of a wet gas flowmeter to provide key parameters and improving the accuracy of a gas-liquid two-phase measurement result of the wet gas flowmeter by accurately measuring the gas and liquid phase contents of the section gas and liquid phases of the gas-liquid two-phase flow pipeline in real time, so that the problem that the testing device is difficult to provide real-time and accurate gas and liquid phase contents in the testing process of obtaining the virtual height correction function of the wet gas flowmeter is solved. The embodiment of the invention is realized by the following technical scheme that the preferred embodiment of the invention provides a device for measuring the section content of a gas-liquid two-phase flow pipeline, which comprises the following components: The gas-liquid supply pipeline system comprises a gas-liquid supply pipeline, and the gas-liquid supply pipeline