Moisture metering gas online calibration device and real-time calibration method

Abstract

The application discloses a kind of wet gas metering gas online calibration device, including horizontal in turn communicating wet gas inlet pipeline, calibration pipeline and wet gas exhaust pipeline, the pipe inner diameter of calibration pipeline is greater than the pipe inner diameter of wet gas inlet pipeline, the pipe core line of wet gas exhaust pipeline is below the pipe core line of calibration pipeline.Radio transceiver assembly is installed on calibration pipeline.It also discloses a kind of wet gas metering gas real-time calibration method, first above device is connected into wet gas recovery pipeline and starts to operate;Then initial ray intensity before passing through pipeline and attenuated ray intensity after passing through pipeline are output by radio transceiver assembly;Finally, calibration gas phase absorption coefficient is calculated by ray absorption formula.The significant effect of the application is that gas phase absorption coefficient in three-phase flow can be calibrated in real time online without stopping well;The calculation parameters required for flowmeter measurement are timely and accurately fed back, which does not affect production and has no hysteresis.

Description

Technical Field

[0001] This invention relates to the measurement of multiphase flow, and more specifically to a device and method for calibrating multiphase flow parameters. Background Technology

[0002] Multiphase flow meters based on radioactive sources have advantages such as high measurement accuracy and rapid response. Their measurement method is based on the absorption coefficients of the three phases of oil, gas, and water. However, the composition of the three phases of oil, gas, and water varies with different operating conditions. Therefore, the absorption coefficients of the three phases of oil, gas, and water to gamma rays will also change under different operating conditions such as different oil wells and different processes. Therefore, manufacturers need to calibrate the absorption coefficients at any time according to the situation.

[0003] Existing technology 1: Existing calibration methods for gas phase absorption coefficients involve vertically setting up the calibration section of the wet gas recovery pipe, with the structure as follows: Figure 1 As shown. Under normal production conditions, valves 1 and 2 remain open; when calibration is required, valves 1 and 2 are closed, the well is shut down, and the well remains stationary for an extended period. The liquid phase settles at the bottom of the calibration section, and calibration is then performed in the upper middle part of the calibration section. The main drawback of this method is the long well shutdown time required, which affects production. Furthermore, the vertical installation of the calibration section in the wet gas recovery pipe results in high installation costs, and the valve maintenance costs are also high.

[0004] Existing technology 2: To avoid production disruptions due to well shutdown calibration, another gas-phase calibration device was later proposed in the industry, the structure of which is as follows: Figure 2 As shown, its structure includes a main pipeline and branch pipelines, which are arranged vertically side by side. During normal production, valve 3 remains closed, while valves 4 and 5 remain open, allowing the three-phase flow to pass through the branch pipelines. When calibration is required, valve 3 is opened, and valves 4 and 5 are closed. The three-phase flow continues through the main pipeline, while the liquid phase in the closed branch pipelines settles at the bottom after a long period of stillness. Calibration is then performed in the upper middle part of the branch pipelines. This method avoids well shutdowns and ensures continuous production. However, the calibrated gas phase absorption coefficient has a certain lag, and when operating conditions change rapidly, the real-time gas phase absorption coefficient cannot be obtained, thus negatively impacting the multiphase flow measurement results. Of course, since the main pipeline and branch pipelines are still installed vertically and have three valves, the installation and maintenance costs remain relatively high. Summary of the Invention

[0005] In view of the shortcomings mentioned in the background art above, the purpose of this invention is to provide an apparatus and method that can both avoid well shutdown and obtain the gas phase absorption coefficient calibration in real time when calibrating the gas phase absorption coefficient.

[0006] The main technical solutions of the involved equipment are as follows:

[0007] A moisture metering gas online calibration device, the key features of which are: it includes a horizontally arranged moisture inlet pipe, a calibration pipe and a moisture outlet pipe, wherein the moisture inlet pipe, the calibration pipe and the moisture outlet pipe are axially connected in sequence, and the inner diameter of the calibration pipe is larger than the inner diameter of the moisture inlet pipe;

[0008] A radiation transceiver assembly is installed on the calibration pipe, and the radiation transceiver assembly transmits and receives radiation horizontally perpendicular to the core wire of the calibration pipe;

[0009] The calibration pipe and the moisture discharge pipe are eccentrically connected, and the core wire of the moisture discharge pipe is located below the core wire of the calibration pipe.

[0010] The main technical solutions involved are as follows:

[0011] A real-time calibration method for moisture metering gas is performed according to the following steps:

[0012] Step 1: Connect the above-mentioned online calibration device for moisture metering gas to the moisture harvesting pipeline and start the moisture harvesting task.

[0013] Step 2: Operate the X-ray transceiver assembly, which outputs the initial X-ray intensity before it passes through the pipe. I 0 and attenuated ray intensity after passing through the pipe I ;

[0014] Step 3: Calculate the gas phase absorption coefficient in the moisture in real time using the following formula. ;

[0015] . Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the prior art.

[0017] Figure 2 This is a schematic diagram of the structure of prior art 2;

[0018] Figure 3 This is a schematic diagram of the structure of an online calibration device for moisture metering gas;

[0019] Figure 4 This is a cross-sectional view of an online calibration device for moisture metering gas;

[0020] Figure 5 This is a cross-sectional view of the calibration pipe 2;

[0021] Figure 6 This is a three-dimensional schematic diagram of the distribution of oil, gas, and water at the 30th second of the test example.

[0022] Figure 7This is a schematic diagram of the oil, gas, and water distribution at the 30th second of the test example.

[0023] Figure 8 for Figure 6 Schematic diagram of oil, gas, and water distribution at mid-section 1;

[0024] Figure 9 for Figure 6 Schematic diagram of oil, gas and water distribution at mid-section 2;

[0025] Figure 10 for Figure 6 A schematic diagram of the distribution of oil, gas, and water at section 3. Detailed Implementation

[0026] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0027] Example 1:

[0028] like Figure 3 As shown, an online calibration device for moisture metering gas includes a horizontally arranged moisture inlet pipe 1, calibration pipe 2, and moisture outlet pipe 3. The moisture inlet pipe 1, calibration pipe 2, and moisture outlet pipe 3 are axially connected in sequence, and the inner diameter of the calibration pipe 2 is larger than the inner diameter of the moisture inlet pipe 1.

[0029] A radiation transceiver assembly 4 is installed on the calibration pipe 2, and the radiation transceiver assembly 4 transmits and receives radiation horizontally perpendicular to the core wire of the calibration pipe 2.

[0030] The calibration pipe 2 and the moisture discharge pipe 3 are eccentrically connected, and the core wire of the moisture discharge pipe 3 is located below the core wire of the calibration pipe 2.

[0031] When the three-phase flow flows in the moisture inlet pipe 1, the liquid phase easily rises along the inner wall of the moisture inlet pipe 1 and is raised. When the three-phase flow flows from the moisture inlet pipe 1 into the calibration pipe 2, the flow velocity of the three-phase flow slows down due to the increased pipe diameter, and the liquid phase is more likely to be deposited at the bottom of the calibration pipe 2. The gas phase is also less likely to entrain the liquid phase. The core line of the moisture outlet pipe 3 is located below the core line of the calibration pipe 2, which can reduce the height of the accumulated liquid phase in the calibration pipe 2. The above two aspects of design can make the upper region of the calibration pipe 2 accumulate pure gas phase, thereby ensuring that effective real-time calibration can be performed in the upper part of the calibration pipe 2.

[0032] As a further preferred embodiment, the diameter of the moisture inlet pipe 1 is equal to the diameter of the moisture outlet pipe 3, and the inner diameter of the calibration pipe 2 is twice the inner diameter of the moisture inlet pipe 1.

[0033] Combination Figure 5It can be seen that the inner circle of the lumen of the moisture discharge pipe 3 is tangent to the inner circle of the lumen of the calibration pipe 2, and its point of tangency is located directly below the core line of the calibration pipe 2 and the core line of the moisture discharge pipe 3.

[0034] The inner circle of the moisture inlet pipe 1 is tangent to the inner circle of the calibration pipe 2, and the point of tangency is located directly below the core line of the calibration pipe 2 and the core line of the moisture inlet pipe 1.

[0035] A transfer pipe section 5 is provided between the moisture inlet pipe 1 and the calibration pipe 2, and between the calibration pipe 2 and the moisture outlet pipe 3. One end of the transfer pipe section 5 is matched and connected to the corresponding port of the moisture inlet pipe 1 or the moisture outlet pipe 3, and the other end of the transfer pipe section 5 is matched and connected to the corresponding port of the calibration pipe 2.

[0036] The X-ray transceiver assembly 4 transmits and receives X-rays horizontally along the diameter of the calibration pipe 2.

[0037] A more specific implementation method is: such as Figure 5 As shown, the X-ray transceiver assembly 4 includes a X-ray emitting mechanism 41 and a X-ray detection mechanism 42. The X-ray emitted by the X-ray emitting mechanism 41 passes horizontally along the radial direction of the calibration pipe 2, and the X-ray detection mechanism 42 acquires the X-ray emitted by the X-ray emitting mechanism 41.

[0038] Example 2:

[0039] A real-time calibration method for moisture metering gas is performed according to the following steps:

[0040] Step 1: Connect the online calibration device for moisture metering gas described in Example 1 to the moisture harvesting pipeline and start the moisture harvesting task.

[0041] Step 2: Operate the X-ray transceiver assembly 4, which outputs the initial X-ray intensity before it passes through the pipe. I 0 and attenuated ray intensity after passing through the pipe I ;

[0042] Step 3: Calculate the gas phase absorption coefficient in the moisture in real time using the following formula. ;

[0043]

[0044] in:

[0045] e It is an independent constant;

[0046] xThe thickness of the medium through which the radiation penetrates; in this embodiment, the radiation transceiver assembly 4 transmits and receives radiation horizontally along the diameter direction of the calibration pipe 2. x That is, the inner diameter of the calibration pipe 2.

[0047] To improve the convenience and efficiency of calibration, relevant intelligent modifications can be made according to existing technologies to enable remote control.

[0048] Example 3:

[0049] A moisture metering system includes a moisture harvesting pipeline and the device described in Example 1. A gamma flow meter is installed on the moisture harvesting pipeline. The gamma flow meter is close to the device described in Example 1. The gamma flow meter can be located upstream of the device described in Example 1. The gas phase absorption coefficient obtained by the method described in Example 2 is input to the gamma flow meter for multiphase flow metering.

[0050] Experimental example:

[0051] The online calibration device for moisture metering gas described in Example 1 was used for simulation experiments. The inner diameter of the moisture inlet pipe 1 and the moisture outlet pipe 3 is 2 inches, and the inner diameter of the calibration pipe 2 is 4 inches. The simulation conditions are VOF model, normal temperature and pressure, the average inlet velocity of the moisture inlet pipe 1 is 2 m / s, and the gas content in the multiphase flow is GVF=96%. Transient simulation was performed.

[0052] After 30 seconds of simulation, the flow patterns in the moisture inlet pipe 1, calibration pipe 2, and moisture outlet pipe 3 stabilized. The simulation results at the 30-second mark are as follows: Figure 6 and Figure 7 As shown in the figure, the oil, gas and water distributions at sections 1, 2 and 3 are respectively as follows: Figure 8 , 9 As shown in Figure 10.

[0053] from Figure 6-10 It can be seen that the liquid phase has poor aggregation at the bottom of the moisture inlet pipe 1. The liquid phase rises along the inner wall of the moisture inlet pipe 1 and becomes crescent-shaped. Therefore, the gas phase absorption coefficient cannot be calibrated in the upper part of the moisture inlet pipe 1. However, the liquid phase in the calibration pipe 2 is basically concentrated at its bottom. There are a large area in the middle and upper parts of the calibration pipe 2 where the gas phase can accumulate, so the gas phase absorption coefficient can be calibrated in the middle and upper parts of the calibration pipe 2.

[0054] It is known that the minimum inner diameter of the calibration pipe 2 should also change accordingly with the changes in flow velocity and gas content. This can be calculated by conventional means in combination with the specific operating conditions.

[0055] Beneficial effects: By using the wet gas metering online calibration device and real-time calibration method of the present invention, the gas phase absorption coefficient in the three-phase flow can be calibrated online in real time as needed without shutting down the well; the calculation parameters required for flow meter measurement are fed back in a timely and accurate manner without affecting production or causing any lag.

[0056] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention. Those skilled in the art, under the guidance of the present invention, can make various similar representations without departing from the spirit and claims of the present invention, and such modifications all fall within the protection scope of the present invention.

Claims

1. A wet gas metering gas on-line calibration device, characterized by: It includes a horizontally arranged moisture inlet pipe (1), calibration pipe (2) and moisture outlet pipe (3), wherein the moisture inlet pipe (1), calibration pipe (2) and moisture outlet pipe (3) are axially connected in sequence, and the inner diameter of the calibration pipe (2) is larger than the inner diameter of the moisture inlet pipe (1); A transceiver assembly (4) is installed on the calibration pipe (2), and the transceiver assembly (4) transmits and receives rays horizontally perpendicular to the core wire of the calibration pipe (2). The calibration pipe (2) and the moisture discharge pipe (3) are eccentrically connected, and the core wire of the moisture discharge pipe (3) is located below the core wire of the calibration pipe (2). The inner circle of the cavity of the moisture discharge pipe (3) is tangent to the inner circle of the cavity of the calibration pipe (2), and its inner tangency point is located directly below the core line of the calibration pipe (2) and the core line of the moisture discharge pipe (3). The inner circle of the moisture inlet pipe (1) is tangent to the inner circle of the calibration pipe (2), and the point of tangency is located directly below the core line of the calibration pipe (2) and the core line of the moisture inlet pipe (1). A transfer pipe section (5) is provided between the moisture inlet pipe (1) and the calibration pipe (2), and between the calibration pipe (2) and the moisture outlet pipe (3). One end of the transfer pipe section (5) is matched and connected to the corresponding port of the moisture inlet pipe (1) or the moisture outlet pipe (3).

2. The online calibration device for moisture metering gas according to claim 1, characterized in that: The X-ray transceiver assembly (4) includes a X-ray emitting mechanism (41) and a X-ray detection mechanism (42). The X-ray emitted by the X-ray emitting mechanism (41) passes horizontally along the radial direction of the calibration pipe (2), and the X-ray detection mechanism (42) acquires the X-ray emitted by the X-ray emitting mechanism (41).

3. The wet-gas metering gas online calibration device according to claim 1 or 2, characterized in that: The inner diameter of the calibration pipe (2) is twice the inner diameter of the moisture inlet pipe (1).

4. The wet-gas-metered gas online calibration device of claim 1, wherein: The diameter of the moisture inlet pipe (1) is equal to the diameter of the moisture outlet pipe (3).

5. A method of real-time calibration of a wet gas metering gas, characterized by Follow these steps: Step 1: Connect the online calibration device for moisture metering gas according to any one of claims 1-4 to the moisture harvesting pipeline and start the moisture harvesting task. Step 2: Run the X-ray transceiver assembly (4), which outputs the initial X-ray intensity before it passes through the pipe. I 0 and attenuated ray intensity after passing through the pipe I ; Step three, real-time calibration of the gas phase absorption coefficient in the moisture according to the following formula ; ； in: e is a constant; x is the thickness of the ray-penetrating medium.

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