A multiphase flow phase split flow measurement apparatus and method

Abstract

The application discloses a multiphase flow separated phase flow measuring device and method, and relates to the technical field of multiphase flow parameter measurement.The multiphase flow separated phase flow measuring device comprises a liquid level meter, a separator, a fourth pipeline, a third pipeline, a valve three and a valve four;an outlet of a container containing a to-be-measured multiphase flow is communicated with a bottom inlet of the separator, a bottom outlet of the separator is communicated with a liquid inlet of the container containing the to-be-measured multiphase flow through the third pipeline; a top outlet of the separator is communicated with the liquid inlet of the container containing the to-be-measured multiphase flow through the fourth pipeline; the valve three is arranged on the third pipeline, the valve four is arranged on the fourth pipeline; and the liquid level meter is arranged in the separator.The application can simultaneously measure the multiphase flow separated phase flow without using multiple measurement technologies.

Description

Technical Field

[0001] This invention relates to the field of multiphase flow parameter measurement technology, and in particular to a multiphase flow phase separation flow measurement device and method. Background Technology

[0002] Multiphase flow parameter measurement is a key and challenging area of ​​research in fields such as petroleum, textiles, chemicals, and water conservancy. This includes parameters such as temperature, pressure, flow rate, and phase fraction. Among these, measuring phase fraction flow rate is a crucial aspect of multiphase flow parameter measurement. Taking the most common oil-gas-water multiphase flow as an example, commonly used methods for measuring phase fraction flow rate include density method, capacitance method, conductivity method, and fiber optic method. However, the density method is susceptible to contamination and cannot measure gas phase fraction. The capacitance and conductivity methods are designed for measuring water phase fraction but cannot measure the fractions of other phases. The fiber optic method, used for measuring gas phase fraction, suffers from significant measurement errors. Therefore, existing methods primarily involve separating the multiphase flow and then using multiple measurement techniques to measure the phase fraction separately. This approach is complex, cumbersome, and prone to large errors, making simultaneous measurement of multiphase flow phase fraction difficult. Therefore, a device is needed that can simultaneously measure the phase fraction of multiphase flow without employing multiple measurement techniques. Summary of the Invention

[0003] The purpose of this invention is to provide a multiphase flow fraction measurement device and method that can simultaneously measure the multiphase flow fraction without employing multiple measurement techniques.

[0004] To achieve the above objectives, the present invention provides the following solution:

[0005] A multiphase flow separation flow measurement device, comprising:

[0006] Level gauge, separator, fourth pipeline, third pipeline, valve three and valve four;

[0007] The outlet of the container holding the multiphase flow to be tested is connected to the bottom inlet of the separator; the bottom outlet of the separator is connected to the inlet of the container holding the multiphase flow to be tested through the third pipe; the top outlet of the separator is connected to the inlet of the container holding the multiphase flow to be tested through the fourth pipe; valve three is installed on the third pipe; valve four is installed on the fourth pipe; and the level gauge is installed inside the separator.

[0008] Optionally, the multiphase flow separation flow measurement device further includes a pressure gauge disposed within the separator.

[0009] Optionally, the multiphase flow separation flow measurement device further includes a thermometer disposed within the separator.

[0010] Optionally, the multiphase flow separation flow measurement device further includes: a second pipe and a second valve; the outlet of the container holding the multiphase flow to be measured is connected to the bottom inlet of the separator through the second pipe, and the second valve is installed on the second pipe.

[0011] Optionally, the multiphase flow separation flow measurement device further includes: a merging pipe, wherein the bottom outlet of the separator is connected to the merging pipe via the third pipe; the top outlet of the separator is connected to the merging pipe via the fourth pipe; the merging pipe is connected to the inlet of the container holding the multiphase flow to be measured; and the valve is disposed between the intersection of the merging pipe and the third pipe and the bottom outlet of the separator.

[0012] Optionally, the multiphase flow separation flow measurement device further includes: a first pipe and a valve; the second pipe and the merging pipe are connected through the first pipe, and the valve is installed on the first pipe.

[0013] A method for measuring the phase-separated flow rate of a multiphase flow, applied to the aforementioned multiphase flow rate measuring device, the method comprising:

[0014] Open valves three and four, and introduce the multiphase flow to be measured into the separator from the container containing the multiphase flow to be measured;

[0015] When the lower interface of the least dense phase in the multiphase flow to be measured in the separator reaches the top of the separator, valve four is closed, and the level gauge measures the descent rate of the lower interface of each phase in the multiphase flow to be measured in the separator, except for the phase with the highest density.

[0016] When the lower interface of the phase with the lowest density in the multiphase flow to be measured in the separator reaches the bottom of the separator, open valve four and close valve three. The level gauge measures the rising speed of the upper interface of the phase with the highest density in the multiphase flow to be measured in the separator.

[0017] The flow rate of each phase is obtained by measuring the descent velocity of the lower interface of each phase (excluding the phase with the highest density) and the rise velocity of the upper interface of the phase with the highest density in the multiphase flow under test in the separator.

[0018] Optionally, the flow rate of each phase is obtained based on the descent velocity of the lower interface of each phase (excluding the phase with the highest density) and the rise velocity of the upper interface of the phase with the highest density in the multiphase flow under test within the separator. Specifically, this includes:

[0019] The flow rates of each phase in the multiphase flow under test, excluding the phase with the highest density, are obtained based on the descent velocity of the lower interface of each phase in the multiphase flow under test within the separator and the inner diameter of the separator.

[0020] The flow rate of the densest phase in the multiphase flow under test within the separator is obtained based on the rising velocity of the upper interface of the phase with the highest density in the multiphase flow under test within the separator and the inner diameter of the separator.

[0021] Optionally, the flow rates of each phase in the multiphase flow under test within the separator, excluding the phase with the highest density, are obtained based on the descent velocity of the lower interface of each phase and the inner diameter of the separator. Specifically:

[0022] According to the formula or Calculate the flow rates of each phase in the multiphase flow under test within the separator, excluding the phase with the highest density, where the density of the i-th phase is less than the density of the (i+1)-th phase. i V represents the flow rate of the i-th phase in the multiphase flow being measured within the separator. i Let represent the descent velocity of the i-th phase in the multiphase flow under test within the separator, d represent the inner diameter of the separator, T represent the temperature measured by the thermometer, P represent the pressure measured by the pressure gauge, n represent the total number of phases in the multiphase flow under test within the separator, and || represent the absolute value.

[0023] Optionally, the flow rate of the densest phase in the multiphase flow under test within the separator is obtained based on the rise velocity of the upper interface of the phase with the highest density in the multiphase flow under test within the separator and the inner diameter of the separator, specifically:

[0024] According to the formula or Calculate the flow rate of the phase with the highest density in the multiphase flow being measured within the separator, where F n V represents the flow rate of the phase with the highest density in the multiphase flow being measured within the separator. n | represents the rise velocity of the upper interface of the phase with the highest density in the multiphase flow under test in the separator, and | represents the absolute value.

[0025] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0026] This invention relates to a multiphase flow fractionation measurement device, comprising: a level gauge, a separator, a fourth pipe, a third pipe, a third valve, and a fourth valve; the outlet of a container holding the multiphase flow to be measured is connected to the bottom inlet of the separator, and the bottom outlet of the separator is connected to the inlet of the container holding the multiphase flow to be measured via the third pipe; the top outlet of the separator is connected to the inlet of the container holding the multiphase flow to be measured via the fourth pipe; the third valve is mounted on the third pipe, and the fourth valve is mounted on the fourth pipe; the level gauge is located inside the separator, eliminating the need to separate the multiphase flow to be measured. This single device is sufficient to measure the multiphase flow fractionation, eliminating the need for multiple measurement techniques and allowing for simultaneous measurement of the multiphase flow fractionation. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A schematic diagram of the overall structure of the multiphase flow separation flow measurement device provided by the present invention;

[0029] Figure 2 This is a schematic diagram of the liquid level gauge provided in an embodiment of the present invention.

[0030] Symbol explanation:

[0031] 101-Valve One, 102-Valve Two, 103-Valve Three, 104-Valve Four, 201-Level Gauge, 202-Level Gauge Head, 203-Level Gauge Probe Rod, 301-Thermometer, 401-Pressure Gauge, 501-Separator, 601-Medium One, 602-Medium Two, 603-Medium Three, 604-Medium Interface One, 605-Medium Interface Two. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] like Figure 1 As shown, this embodiment of the invention provides a multiphase flow separation flow measurement device, including: a level gauge 201, a separator 501, a fourth pipe, a third pipe, a third valve 103, and a fourth valve 104; the outlet of a container holding the multiphase flow to be measured is connected to the bottom inlet of the separator 501, the bottom outlet of the separator 501 is connected to the inlet of the container holding the multiphase flow to be measured through the third pipe; the top outlet of the separator 501 is connected to the inlet of the container holding the multiphase flow to be measured through the fourth pipe; the third valve is disposed on the third pipe, and the fourth valve is disposed on the fourth pipe; the level gauge 201 is disposed inside the separator 501.

[0035] Quantitative measurement of the gas phase must be combined with the gas temperature and pressure in order to convert it to the gas volume under standard conditions. Temperature and pressure are also important indicators of the fluid being measured. Therefore, in practical applications, multiphase flow separation flow measurement equipment also includes: a pressure gauge 401 installed in the separator 501 and a thermometer 301 installed in the separator 501.

[0036] In practical applications, the multiphase flow separation flow measurement device also includes: a second pipe and a second valve 102; the outlet of the container holding the multiphase flow to be measured is connected to the bottom inlet of the separator 501 through the second pipe, and the second valve 102 is installed on the second pipe.

[0037] In practical applications, the level gauge 201 consists of two parts: the level gauge head 202 and the level gauge probe rod 203, such as... Figure 2 As shown, the level gauge probe rod 203 is located inside the separator 501 and is used to detect the position, rising and falling speed of the medium interface (the lower interface of each phase).

[0038] In practical applications, the level gauge 201, pressure gauge 401, and thermometer 301 are installed on top of the separator 501.

[0039] In practical applications, the multiphase flow separation flow measurement device further includes: a merging pipe, wherein the bottom outlet of the separator 501 is connected to the merging pipe through the third pipe; the top outlet of the separator 501 is connected to the merging pipe through the fourth pipe; the merging pipe is connected to the inlet of the container holding the multiphase flow to be measured; and the valve is disposed between the intersection of the merging pipe and the third pipe and the bottom outlet of the separator 501.

[0040] In practical applications, the multiphase flow separation flow measurement device further includes: a first pipe and a valve 101; the second pipe and the merging pipe are connected through the first pipe, and the valve 1 is installed on the first pipe.

[0041] This invention also provides a method for measuring the phase-separated flow rate of a multiphase flow, applied to the multiphase flow rate measuring device described in the above embodiments. The method includes:

[0042] Open valves 3 (103) and 4 (104) to introduce the multiphase flow to be measured into the separator 501.

[0043] When the lower interface of the phase with the lowest density in the multiphase flow to be measured in separator 501 reaches the top of separator 501, valve 104 is closed, and level gauge 201 measures the descent rate of the lower interface of each phase in the multiphase flow to be measured in separator 501, except for the phase with the highest density.

[0044] When the lower interface of the phase with the lowest density in the multiphase flow to be measured in the separator 501 reaches the bottom of the separator 501, valve 4 104 is opened and valve 3 103 is closed. The level gauge 201 measures the rising speed of the upper interface of the phase with the highest density in the multiphase flow to be measured in the separator 501.

[0045] The flow rate of each phase is obtained by measuring the descent velocity of the lower interface of each phase in the multiphase flow under test in separator 501 (excluding the phase with the highest density) and the rise velocity of the upper interface of the phase with the highest density in the multiphase flow under test in separator 501.

[0046] In practical applications, the flow rates of each phase are obtained based on the descending velocity of the lower interface of each phase in the multiphase flow under test within separator 501 (excluding the phase with the highest density) and the rising velocity of the upper interface of the phase with the highest density in the multiphase flow under test within separator 501. Specifically, this includes:

[0047] The flow rates of each phase in the multiphase flow under test within separator 501, excluding the phase with the highest density, are obtained based on the descent velocity of the lower interface of each phase and the inner diameter of separator 501.

[0048] The flow rate of the densest phase in the multiphase flow under test within separator 501 is obtained based on the rising velocity of the upper interface of the phase with the highest density in separator 501 and the inner diameter of separator 501.

[0049] In practical applications, the flow rates of each phase in the multiphase flow under test within separator 501, excluding the phase with the highest density, are obtained based on the descent velocity of the lower interface of each phase and the inner diameter of separator 501. Specifically:

[0050] According to the formula or Calculate the flow rate of each phase in the multiphase flow under test within separator 501, excluding the phase with the highest density, where the density of the i-th phase is less than the density of the (i+1)-th phase. i V represents the flow rate of the i-th phase in the multiphase flow to be measured within separator 501. i denoted by d, where d represents the descent velocity of the i-th phase in the multiphase flow under test within separator 501, d represents the inner diameter of separator 501, T represents the temperature measured by thermometer 301, P represents the pressure measured by pressure gauge 401, n represents the total number of phases in the multiphase flow under test within separator 501, and || represents the absolute value.

[0051] In practical applications, the flow rate of the phase with the highest density in the multiphase flow under test within separator 501 is obtained based on the rising velocity of the upper interface of the phase with the highest density in the multiphase flow under test within separator 501 and the inner diameter of separator 501. Specifically:

[0052] According to the formula or Calculate the flow rate of the phase with the highest density in the multiphase flow being measured within separator 501, where F n V represents the flow rate of the phase with the highest density in the multiphase flow being measured within separator 501. n | represents the rising velocity of the upper interface of the phase with the highest density in the multiphase flow under test in separator 501, and | represents the absolute value.

[0053] This invention features ingenious design, low cost, simple principle, no moving parts, no flow obstruction, high reliability, high accuracy, real-time performance, and simultaneous measurement of multiphase flow rates. It can achieve accurate real-time measurement of the flow rates of various media with different densities (such as oil-gas-water multiphase flow formed in petroleum production).

[0054] This invention applies the above-mentioned multiphase flow separation flow measurement equipment to the oil-gas-water multiphase flow formed in petroleum production for phase separation flow measurement, as detailed below:

[0055] First, there is a test pipeline at the oil wellhead. Inside the test pipeline is the multiphase flow to be measured. The inlet pipeline of the multiphase flow separation flow measurement equipment is connected to the outlet of the test pipeline, and the outlet pipeline is connected to the inlet of the test pipeline. The inlet of valve 2 102 is connected to the inlet of valve 1 101 through a pipeline. The outlet of valve 2 102 is connected to the bottom of separator 501 through a pipeline. The inlet of valve 3 103 is connected to the bottom of separator 501 through a pipeline. The outlet of valve 3 103 is connected to the outlet of valve 1 101 through a pipeline. The inlet of valve 4 104 is connected to the top of separator 501 through a pipeline. The outlet of valve 4 104 is connected to the outlet of valve 3 103 and the outlet of valve 1 101 through a pipeline.

[0056] Figure 1 The following description uses a multiphase flow with three media as an example, where the density of medium 601 (first phase) is less than the density of medium 602 (second phase) and less than the density of medium 603 (third phase). Medium 601, medium 602, and medium 603 represent the gas phase, oil phase, and water phase in the oil-gas-water multiphase flow.

[0057] The specific measurement steps for multiphase flow separation flow measurement using multiphase flow separation flow measurement equipment are as follows:

[0058] (1) When the multiphase flow meter stops measuring, open valve 101 and close valves 2102, 3103 and 4104.

[0059] (2) When the multiphase flow meter starts measuring, close valve 101 and open valves 2102, 3103 and 4104.

[0060] (3) The fluid enters the separator 501 through valve 2 102. The density of medium 2 602 is less than that of medium 3 603. Medium 3 603 will flow away from the bottom. Medium 1 601 and medium 2 602 accumulate in the container, causing medium interface 1 604 (the lower interface of the first phase) to rise. When medium interface 1 604 in the separator 501 reaches the top of the separator 501, valve 4 104 is closed. Medium interface 1 604 and medium interface 2 605 drop. The level gauge 201 measures the drop speed V1 and V2 of medium interface 1 604 and medium interface 2 605 in real time.

[0061] (4) When the medium interface 1 604 in separator 501 reaches the bottom of separator 501, open valve 4 104 and close valve 3 103. Medium 1 601 begins to flow out from the top through valve 4. Medium 2 602 and medium 3 603 begin to accumulate in the container. Medium interface 1 604 and medium interface 2 605 begin to rise. The level gauge 201 measures the rising speed of medium interface 2 605 and V3 in real time.

[0062] (5) When there are n kinds of media with different densities and they are immiscible with each other, the media are respectively media 1, 2, …, n from the smallest density to the largest density, and the interfaces are respectively interfaces 1, 2, …, n - 1 from top to bottom. Assuming the inner diameter of the container is d, in step (3), the descending speeds of interfaces 1, 2, …, n - 1 can be obtained as V1, V2, …, V n-1 , and in step (4), the ascending speed of interface n - 1 can be obtained as V n , where the flow rate calculation of medium 1 is Medium 2 is Medium i is (1 < i < n). In step (4), the ascending speed of interface n - 1 is V n , then the flow rate of medium n is: In this way, the phase-separated flow rate is calculated. If the volume of a certain medium is sensitive to temperature and pressure (such as the gas phase), then the corresponding formula needs to be added with the representations of temperature and pressure, such as and

[0063] In this embodiment, the flow rate of medium 601 is or The flow rate of medium 602 is or The flow rate of medium 603 is or

[0064] The method for measuring the phase-separated flow rate of multiphase flow mainly realizes the rise and fall of the medium interface in the separator by alternately opening and closing valve three and valve four. During the rise and fall process, the liquid level gauge measures the position, rise and fall speeds of the medium interface in real time, and then calculates the phase-separated flow rate of multiphase flow.

[0065] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other.

[0066] In this article, specific examples are used to elaborate on the principle and implementation manner of the present invention. The descriptions of the above embodiments are only used to help understand the method of the present invention and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A method of multiphase flow separation and flow rate measurement, comprising: The application is applied to a multiphase flow phase separation flow measurement device, which comprises a liquid level meter, a separator, a fourth pipeline, a third pipeline, a valve three, a valve four, a thermometer arranged in the separator and a pressure gauge arranged in the separator; a liquid outlet of a container containing a to-be-measured multiphase flow is communicated with a bottom inlet of the separator, a bottom outlet of the separator is communicated with a liquid inlet of the container containing the to-be-measured multiphase flow through the third pipeline; a top outlet of the separator is communicated with the liquid inlet of the container containing the to-be-measured multiphase flow through the fourth pipeline; the valve three is arranged on the third pipeline, the valve four is arranged on the fourth pipeline; the liquid level meter is arranged in the separator, and the multiphase flow phase separation flow measurement method comprises the following steps: opening the valve three and the valve four, and introducing the to-be-measured multiphase flow into the separator through the container containing the to-be-measured multiphase flow; when the lower interface of the phase with the smallest density in the to-be-measured multiphase flow in the separator reaches the top of the separator, closing the valve four, and measuring the descending speed of the lower interface of each phase except the phase with the largest density in the to-be-measured multiphase flow in the separator by the liquid level meter; when the lower interface of the phase with the smallest density in the to-be-measured multiphase flow in the separator reaches the bottom of the separator, opening the valve four, closing the valve three, and measuring the ascending speed of the upper interface of the phase with the largest density in the to-be-measured multiphase flow in the separator by the liquid level meter; obtaining the flow of each phase according to the descending speed of the lower interface of each phase except the phase with the largest density in the to-be-measured multiphase flow in the separator and the ascending speed of the upper interface of the phase with the largest density in the to-be-measured multiphase flow in the separator.

2. The multiphase flow and separation flow rate measurement method of claim 1, wherein, obtaining the flow of each phase according to the descending speed of the lower interface of each phase except the phase with the largest density in the to-be-measured multiphase flow in the separator and the ascending speed of the upper interface of the phase with the largest density in the to-be-measured multiphase flow in the separator, specifically comprising: obtaining the flow of each phase except the phase with the largest density in the to-be-measured multiphase flow in the separator according to the descending speed of the lower interface of each phase except the phase with the largest density in the to-be-measured multiphase flow in the separator and the inner diameter of the separator; obtaining the flow of the phase with the largest density in the to-be-measured multiphase flow in the separator according to the ascending speed of the upper interface of the phase with the largest density in the to-be-measured multiphase flow in the separator and the inner diameter of the separator.

3. The multiphase flow and separation flow rate measurement method of claim 2, wherein, obtaining the flow of each phase except the phase with the largest density in the to-be-measured multiphase flow in the separator according to the descending speed of the lower interface of each phase except the phase with the largest density in the to-be-measured multiphase flow in the separator and the inner diameter of the separator, specifically comprising: The flow rate of each phase of the multiphase flow to be measured in the separator, except the phase with the largest density, is calculated according to the formula or wherein the density of the ith phase is less than the density of the i+1th phase, denotes the flow rate of the ith phase of the multiphase flow to be measured in the separator, denotes the falling velocity of the ith phase of the multiphase flow to be measured in the separator, d denotes the inner diameter of the separator, T denotes the temperature measured by the thermometer, P denotes the pressure measured by the pressure gauge, and n denotes the total number of phases of the multiphase flow to be measured in the separator, denotes the absolute value.

4. The multiphase flow and separation flow measurement method of claim 3, wherein, obtaining the flow of the phase with the largest density in the to-be-measured multiphase flow in the separator according to the ascending speed of the upper interface of the phase with the largest density in the to-be-measured multiphase flow in the separator and the inner diameter of the separator, specifically comprising: According to the formula or Calculate the flow rate of the phase with the highest density in the multiphase flow being measured within the separator, where, This represents the flow rate of the phase with the highest density in the multiphase flow being measured within the separator. This represents the rise velocity of the upper interface of the phase with the highest density in the multiphase flow being measured within the separator. It represents the absolute value.

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