KR102124570B1 - Flow measurement method using vent nozzle - Google Patents

Abstract

An objective of the present invention is to provide a flow measurement method using a vent nozzle capable of measuring a flow rate of flare gas with high accuracy even in a pipe having a curved shape and a pipe drawn thereon. The present invention includes: an insertion step of inserting a flow meter into the inside of the pipe; a measuring step of measuring the speed and density of flare gas using the flow meter disposed inside the pipe in the inserting step; a calculating step of calculating the flow rate of the flare gas based on a velocity value and a density value of the flare gas measured in the measuring step; and an analysis step of analyzing a flow value of the flare gas calculated in the calculating step.

Description

Flow measurement method using vent nozzle {FLOW MEASUREMENT METHOD USING VENT NOZZLE}

The present invention relates to a flow measurement method using a vent nozzle, specifically, by installing a flow meter using a vent nozzle pre-installed in a pipe through which flare gas flows in an existing flare system, thereby providing It relates to a flow measurement method that can be easily measured with a relatively high accuracy.

In general, the flare gas is a waste gas generated from an oil refinery or a petrochemical plant, and refers to a gas having volatile and flammable flare gas. Flare consists of a number of pipelines (pipes) flowing, a flare header for collecting discharged gas or liquid, a knockout drum for separating and collecting liquid delivered from the flare gas, a pilot burner as an incineration tower, an ignition device, etc. A flare system comprising a flare stack that burns and releases gas, a seal drum to prevent an accident from being caused by a flame backflowed from the flare stack, and the like is provided. Accordingly, the flare gas is discharged to the outside through an exhaust gas treatment device called a flare stack. That is, the flare gas is delivered to the flare stack through a pipe, and can be burned in the flare stack and discharged into the atmosphere.

On the other hand, since the flare stack is connected to a plurality of pipes and receives flare gas, it is sensitively affected by the internal pressure fluctuation of the pipe. In other words, various factors such as the combustion efficiency of flare gas by the flare stack and the structural stability of the flare stack are affected by the internal pressure of the pipe or the flow state of the flare gas.

Accordingly, the flow rate of the flare gas flowing along the pipe is measured, and the presence or absence of gas flow in the pipe is determined according to the measured result, or the presence or absence of a flare gas leak using the difference data between the flow points is determined. It can be said that it is very important to prevent problems that may occur in the flare stack and the flare system as a whole.

Moreover, when the flow rate of flare gas flowing in the flare system is monitored from various locations, the entire flow rate can be grasped from a simultaneous point of view, so that the control direction of the flare system can be determined and performed immediately. It is possible to collect appropriate data necessary for efficient management.

However, in order to apply the existing flow measurement method to the already installed flare system, the process of hot tapping the pipe to insert and install the flow meter in a location where the flow meter is not installed is required. There is a disadvantage that installation work for building a flow meter monitoring system is very cumbersome and incurs high cost.

That is, in the past, the flow rate of flare gas was measured by drilling a pipe and installing a known flow meter at the perforated position, but this method has a problem of low efficiency in terms of cost and stability.

In addition, the existing flow measurement method, the flowmeter at a point (preferably a length of at least 10 times the diameter of the pipe away from the bent pipe) formed in a long straight form with no curved pipe located around (especially upstream). In the case of installation, since it has a stable and uniform flow distribution at the corresponding position, it was possible to measure the flow rate relatively accurately by placing the flowmeter measuring part in the center of the pipe, but to a pipe having a curved shape or a pipe located adjacent to the upstream direction When a flow meter is installed, there is a problem in that the flow of flare gas in the pipe is not uniformly distributed, and thus the flow rate cannot be accurately measured.

Therefore, the applicant has proposed the present invention in order to solve the above problems, and related prior art documents include fluids moving through a tube or groove-shaped flow path of Korean Patent Publication No. 10-2004-0065555. There is a method of measuring the flow rate.

The present invention is to solve the above problems, stably measure the flow rate of the flare gas flowing along the pipe, and also, in a pipe having a curved shape and a pipe drawn in it, the flow rate of the flare gas with high accuracy It is an object to provide a flow measurement method using a vent nozzle that can be measured.

The present invention, the insertion step of inserting the flow meter into the interior of the pipe; A measuring step of measuring the velocity and density of flare gas using the flow meter disposed inside the pipe in the insertion step; A calculating step of calculating a flow rate of the flare gas based on the velocity value and the density value of the flare gas measured in the measuring step; And an analysis step of analyzing the flow value of the flare gas calculated in the calculation step.

In addition, in the insertion step, the flow meter may be inserted into the pipe through a vent nozzle provided in the pipe.

In addition, the velocity of the flare gas measured in the measuring step may be calculated using a pressure difference generated due to the flow of the flare gas.

In addition, the velocity of the flare gas measured in the measurement step is the same as the voltage measured in the direction facing the flow direction of the flare gas (Total Pressure) and the static pressure measured at the point where the flow meter is inserted ( After calculating the dynamic pressure), it can be calculated using the Bernoulli equation based on the calculated dynamic pressure value.

In addition, when the pipe is in the form of a curved tube or in a position affected by non-uniform flow due to the curved tube, a speed distribution analysis step of determining and correcting the flow profile of the flare gas through CFD (Computational fluid dynamics) is further included. Can be.

In addition, the flow meter may include a measurement probe in which a lengthwise lower end portion is inserted into the pipe through a flow path formed in the vent nozzle; A speed measuring unit measuring a flare gas speed while connected to the measuring probe; Density measurement unit for measuring the density of the flare gas connected to the measurement probe; And a data analysis unit that calculates a flow rate of the flare gas based on the values measured by the speed measurement unit and the density measurement unit, and stores and analyzes the calculated flow rate.

In addition, the measuring probe, the round surface of the semi-circular shape disposed to face the flow direction of the flare gas; A chamfer provided on the rear side of the round surface with a predetermined depth; And a vertical surface that divides the chamfered portion and connects both ends of the round surface in the width direction to each other.

In addition, the speed measuring unit, a first pipe connected to one end in the longitudinal direction to the first pressure sphere formed on the round surface; A second pipe having one end longitudinally connected to a second pressure port formed on the vertical surface; And it is connected to the other end of the first pipe in the longitudinal direction and the other end of the second pipe in communication, the pressure of the pressure generated in the first pipe and the pressure generated in the second pipe of the flare gas It may include; a first sensor unit for measuring the speed.

In addition, the density measuring unit, the third pipe is connected to one end in the longitudinal direction to the gas inlet formed on the round surface; A fourth pipe to which a lengthwise one end is communicatively connected to a gas outlet formed on an outer surface of the measuring probe in which the chamfer is not disposed; It may include; a second sensor unit which is connected to the other end of the third pipe in the longitudinal direction and the other end of the fourth pipe in communication, and measures the density of flare gas flowing through the third pipe.

The flow measurement method using the vent nozzle according to the present invention allows the flowmeter to be freely installed in multiple locations and measure the flow rate without performing a hot tapping operation for drilling the pipe, thereby flaring the entire flare system as well as one point. It is possible to stably measure the flow rate of gas.

In addition, in the flow measurement method using a vent nozzle according to the present invention, the velocity of the flare gas is measured by a pressure calculation method that is not affected by turbulent/laminar flow according to the flow rate of the flare gas, and the velocity value of the flare gas is measured. Since the flow rate is calculated, it is possible to improve the accuracy of the fluid measurement in the pipe regardless of the position where the flow rate is measured.

In addition, the flow measurement method using a vent nozzle according to the present invention measures the flow of the flare gas by using the vent nozzle of a pre-installed flare system provided in a plurality along the longitudinal direction of the pipe, so a separate complicated operation for installing a flow meter Without measuring the flow of flare gas at various points, it is possible to accurately identify the gas leak point, and accurately understand the pressure fluctuations in each section of the pipe.

In addition, the flow measurement method using the vent nozzle according to the present invention, it is possible to measure the flow rate of the flare gas with high accuracy even in a pipe having the shape of a curved tube.

1 is a flow chart of a flow measurement method using a vent nozzle according to the present invention.
2 is a view showing the configuration of a flow meter used in a flow measurement method using a vent nozzle according to the present invention.
Figure 3 is a photograph showing a state in which the flow meter is mounted on the vent nozzle provided on the top of the pipe.
4 is a diagram showing the velocity distribution of flare gas flowing in a curved pipe measured using CFD.
5 is an enlarged perspective view showing area A of the measurement probe shown in FIG. 2.
FIG. 6 is a side view showing the internal appearance of area A of the measurement probe shown in FIG. 2.
7 is a view showing a first sensor unit and a second sensor unit provided inside the case shown in FIG. 2.
Fig. 8 is a plan sectional view of the lower end of the measuring probe as viewed from above.

Advantages and features of the present invention, and methods for achieving them will be clarified with reference to embodiments described below in detail together with the accompanying drawings.

However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, and only the present embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains. It is provided to completely inform the person having the scope of the invention, and the present invention is only defined by the scope of the claims.

Hereinafter, a flow rate measuring method using a vent nozzle according to an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 8. In describing the present invention, detailed descriptions of related known functions or configurations are omitted so as not to obscure the subject matter of the invention.

The flow measurement method using a vent nozzle according to an embodiment of the present invention can be said to be characterized by measuring the flow rate of the flare gas with high accuracy in a pipe through which the flare gas flows. In particular, the composition of the flare gas is accurately It can be said to be characterized by accurately measuring the density and dynamic pressure of the flare gas even in a difficult state to grasp.

Moreover, it can be said that the flow of flare gas is characterized by being able to grasp the exact flow value to be obtained even in a non-uniform curved tube or near a curved tube.

1 to 3, a flow measurement method using a vent nozzle according to an embodiment of the present invention,

Insertion step (S100) of inserting the flow meter 100 into the interior of the pipe (P); A measuring step (S200) of measuring the speed and density of flare gas by using the flow meter 100 disposed inside the pipe P in the insertion step S100; A calculating step (S300) of calculating the flow rate of the flare gas based on the velocity value and the density value of the flare gas measured in the measuring step (S200); And an analysis step (S400) of analyzing the flow value of the flare gas calculated in the calculation step (S300).

First, in the insertion step (S100), as shown in Figure 3, the step of inserting the flow meter 100 into the interior of the pipe (P) through the vent nozzle (N) provided on the top of the pipe (P) can do.

For reference, the vent nozzle (N) is provided with a plurality of spaced apart in the longitudinal portion of the pipe (P) to control the pressure fluctuation of the pipe (P), which can be opened or closed by a known valve device It has a structure.

Therefore, in the inserting step (S100), the flow meter 100 is inserted into the pipe P using at least one of the plurality of vent nozzles N provided at regular intervals in the longitudinal portion of the pipe P. can do.

In the measurement step (S200), the density of the flare gas flowing in the pipe P is measured using the flow meter 100, and in addition, flare is performed using a pressure difference generated by the flow of the flare gas. It is a step to measure the speed of gas.

That is, the velocity of the flare gas measured in the measurement step (S200) is the voltage measured in the direction facing the flow direction of the flare gas (Total Pressure) and the static pressure measured at the point where the flow meter 100 is inserted ( It can be said that the dynamic pressure is calculated using Static Pressure, and then calculated using the Bernoulli equation based on the calculated dynamic pressure value.

In addition, the density of the flare gas measured in the measuring step S200 may be measured by a known quartz oscillator gas sensor or the like that vibrates using the flare gas as a medium.

For reference, the detailed configuration of the flow meter 100 used to measure the density and speed of the flare gas in the measurement step (S200) will be described in detail below.

On the other hand, when the pipe P in which the flow meter 100 is inserted is in the form of a curved tube or in a position affected by uneven flow due to the curved tube, after determining the flow profile of the flare gas through CFD (Computational fluid dynamics) The speed distribution analysis step of correcting (S150); may further include.

That is, in the case of a straight pipe through which the fluid can flow uniformly without resistance to flow, among the various sections of the pipe through which the flare gas flows, the velocity distribution of the flare gas in the pipe has a substantially uniform shape (central point The fastest and slowest point on the inside of the pipe, like a normal distribution graph). Therefore, in such a position, it is possible to accurately grasp how the velocity of the flare gas measured in the relationship between the length of the flow meter 100 to be inserted and the diameter of the pipe P has a relationship with the average fluid velocity in the corresponding section, It is difficult to determine how the velocity measured by the flow meter 100 has a relationship with the velocity of the corresponding point at a point where the flow velocity distribution in the pipe is not uniformly predicted, or at a point where the curve is affected.

To solve this problem, when the flow rate distribution in the pipe P in which the flow meter 100 is installed is accurately grasped, it is possible to clearly grasp the relationship between the measured value at the corresponding point and the average velocity.

In other words, even if the flow meter 100 is inserted at a point of the pipe P having a shape of a curved tube, or even when inserted at a point of the pipe P having a straight shape, the point of the pipe P and the curved portion of the pipe P When placed in close proximity and influenced by a non-uniform fluid flow, the flow profile of the flare gas can be determined and corrected through CFD (Computational fluid dynamics) in the velocity distribution analysis step (S150 ).

The speed distribution analysis step (S150) may be performed by obtaining 3D data of the pipe through a 3D scan or actual measurement, or a value on a design drawing before the measurement step (S200), for performing CFD The commercial program STAR-CCM+ can be used. For reference, FIG. 4 shows a state in which the velocity distribution of the flare gas is grasped at the curved portion of the pipe P and the straight portion disposed close to the curved portion using CFD.

Therefore, when the flow meter 100 is inserted, that is, the position where the vent nozzle N is provided is a curved portion of the pipe P or a straight portion disposed close to the curved portion, the speed distribution analysis step (S150) ) To further correct the flow profile of the flare gas, and then perform the measurement step S200 to measure the flow rate of the flare gas in the curved pipe P.

The calculation step (S300), as described above, is a step of calculating the flow rate of the flare gas based on the velocity value and the density value of the flare gas measured in the measurement step (S200), through the vent nozzle (N) The flow of the flare gas at the point where the flow meter 100 is inserted into the pipe P may be calculated.

In the calculation step (S300), the calculation unit provided in the flow meter 100 may calculate the flow rate of the flare gas based on the velocity value and the density value of the flare gas, and the calculated value is data of the flow meter 100 to be described later. It may be stored in the analysis unit 140 and compared with the flow value of the flare gas calculated at another longitudinal point of the pipe P.

For reference, specification data of the pipe P is stored in the calculation unit such as shape, curvature, thickness, inner diameter and outer diameter of the pipe P, and this data and measured values measured in the measuring step S200 are stored. It can be used to calculate the flow rate of the flare gas.

The analysis step (S400), as described above, by analyzing the flow rate of the flare gas calculated in the calculation step (S300), it can be said to be a step to determine whether there is an abnormality in the pipe P or a leak point of the flare gas. have.

That is, since a plurality of vent nozzles (N) are disposed at a distance from each other on one pipe (P), the flow rate values calculated at each of the points where the plurality of vent nozzles (N) are provided using the flow meter (100) Compared with each other, it is possible to grasp the point of leakage of flare gas and, in addition, the pressure state of the pipe P.

In addition, the state of the plurality of pipes P connected to the flare stack can also be identified in the analysis step S400.

Therefore, in the flow measurement method using the vent nozzle according to an embodiment of the present invention, since the flow rate of the flare gas can be measured using the existing vent nozzle N provided in the pipe P, it is hot to puncture the pipe. The flow of flare gas can be measured stably at multiple points without the need for tapping.

In addition, since the velocity of the flare gas is measured by a differential pressure method with less turbulent/laminate flow effect according to the flow velocity of the flare gas, the flow rate value of the flare gas having a low/low flow rate can be measured with high accuracy.

Hereinafter, with reference to FIGS. 2 and 5 to 8, the configuration of the flow meter 100 used in the flow measurement method using the vent nozzle according to an embodiment of the present invention will be described.

As shown in FIGS. 2 and 5 to 8, the flow meter 100 includes a measurement probe (in which a longitudinal lower end portion is inserted into the pipe P through a flow path formed in the vent nozzle N) ( 110); A speed measurement unit 120 configured to measure the speed of the flare gas while connected to the measurement probe 110; Density measurement unit 130 for measuring the density of the flare gas connected to the measurement probe 110; And a data analysis unit 140 that calculates a flow rate of flare gas based on values measured by the speed measurement unit 120 and the density measurement unit 130, and stores and analyzes the calculated flow rate. can do.

First, the measurement probe 110 has a shape of a vertical rod as a whole, and may be inserted in a vertical direction crossing the longitudinal direction of the pipe P through a relatively small diameter vent nozzle N.

A case C in which the first sensor unit 123 of the speed measurement unit 120 and the second sensor unit 133 of the density measurement unit 130 are built is provided at an upper end of the measurement probe 110. , The upper part of the measuring probe 110 including the case C may be a component disposed outside the pipe P.

The lower end of the measuring probe 110, as shown in Figures 5 and 6, the circular surface of the arc-shaped round surface 111 disposed facing the flow direction (A) of the flare gas; A chamfering portion 112 provided with a predetermined depth on the rear side of the round surface 111; And a vertical surface 113 which divides the chamfer 112 and connects both ends of the round surface 111 in the width direction to each other.

That is, the lower part of the measuring probe 110 in the form of a vertical rod having a circular cross section as a whole may have an incision shaped as a'c', and this lower part is used to measure the velocity and density of the flare gas. It can be said to be a part.

The round surface 111 may be disposed to face the flow direction A of the flare gas while having a semicircular curvature. That is, when the lower end of the measurement probe 110 is inserted into the pipe P through the vent nozzle N, the round surface 111 can be said to be disposed facing the flow direction of the flare gas.

In addition, a first pressure sphere 111a for measuring the speed of flare gas may be formed on the round surface 111, and the first pressure sphere 111a is a longitudinal stop portion of the round surface 111. Can be placed on.

In addition, a gas inlet 111b (see FIGS. 6 and 8) for measuring the density of flare gas may be formed on the round surface 111, and the gas inlet 111b is the first pressure inlet 111a. It can be placed on a location that does not interfere with.

The chamfer 112, as described above, the vertical surface 113 connecting the both ends of the width direction of the round surface 111 to each other, and horizontal surfaces extending in the horizontal direction from the top and bottom of the vertical surface 113, respectively (114).

On the other hand, a second pressure sphere 113a for measuring the velocity of flare gas may be formed on the vertical surface 113, and the second pressure sphere 113a is disposed at a longitudinal stopping portion of the vertical surface 113 Can be.

For reference, the first pressure sphere 111a formed on the round surface 111 may be a hole for measuring the voltage at the point where the measurement probe 110 is inserted into the pipe P. On the contrary, the vertical surface The second pressure sphere 113a formed in 113 may be said to be a hole for measuring the static pressure at the point where the measurement probe 110 is inserted into the pipe P.

As described above, the first pressure sphere 111a is provided on the round face 111 facing the flow direction A of the flare gas, and the second pressure sphere is provided on the vertical face 113 opposite to the round face 111 ( The reason for forming 113a) is that, as shown in FIG. 8, the vortex generated when the flare gas comes into contact with the round surface 111 flows in the direction in which the vertical surface 113 is disposed, and the second This is to prevent entry into the pressure port (113a). That is, to prevent the flare gas flowing after contacting the round surface 111 from flowing in the direction in which the second pressure sphere 113a is formed, so that the correct static pressure can be measured at the second pressure sphere 113a. .

Therefore, the first pressure sphere (111a) is preferably formed on the round surface 111 to branch the flare gas in both directions, the second pressure sphere (113a) is branched by the round surface 111 to flow It is preferably formed on a vertical surface 113 that is not affected by flare gas.

Meanwhile, a gas outlet 111c is provided at a lower portion of the measurement probe 110 in which the chamfered portion 112 is not formed, and the gas outlet 111c is a fourth pipe of the density measurement unit 130 to be described later. It can be connected to (132).

The speed measurement unit 120, as shown in Figures 6 and 7, the first pipe 121 is connected to the first pressure port (111a) formed in the round surface 111 in the longitudinal direction so as to be communicatively ); A second pipe 122 having one end longitudinally connected to a second pressure port 113a formed on the vertical surface 113; And the other end of the first pipe 121 and the other end of the second pipe 122 in communication with the other end, the pressure generated in the first pipe 121 and the second pipe 122 It may include; a first sensor unit 123 for measuring the speed of the flare gas using the differential pressure of the pressure generated in the.

The first pipe 121 and the second pipe 122 may be provided along the longitudinal direction of the measuring probe 110 inside the measuring probe 110.

One end of the first pipe 121 in the longitudinal direction, that is, the lower end is communicatively connected to the first pressure sphere 111a as described above, and the other end of the longitudinal direction, that is, the upper end of the first sensor part 123 It can be connected with.

One end of the second pipe 122 in the longitudinal direction, that is, the lower end is communicatively connected to the second pressure sphere 113a as described above, and the other end of the longitudinal direction, that is, the upper end of the second sensor part 123 It can be connected with.

The first sensor unit 123 may be a known differential pressure sensor, and calculates a differential pressure (dynamic pressure) between the pressure generated in the first pipe 121 and the pressure generated in the second pipe 122 , The flare gas velocity can be calculated using the calculated value.

In addition, the speed of the air gas calculated by the first sensor unit 123 may be transmitted to the data analysis unit 140.

The density measurement unit 130, as shown in Figures 6 and 7, the third pipe 131, which is longitudinally connected to the gas inlet 111b formed in the round surface 111 is connected to the pipe; A fourth pipe 132 having one end of the length connected to the gas outlet 111c formed on the outer surface of the measurement probe 110 in which the chamfer 112 is not disposed; The second end of the third pipe 131 and the other end of the length of the fourth pipe 132 is in communication with the other end, the second to measure the density of the flare gas flowing through the third pipe 131 It may include; the sensor unit 133;

The third pipe 131 and the fourth pipe 132 may also be provided along the longitudinal direction of the measuring probe 110 inside the measuring probe 110.

One end of the third pipe 131 in the longitudinal direction, that is, the lower end, is communicatively connected to the gas inlet 111b as described above, and the other end of the longitudinal direction, that is, the upper end of the second sensor unit 133 It can be connected with.

One end of the fourth pipe 132 in the longitudinal direction, that is, the lower end is communicatively connected to the gas outlet 111c as described above, the other end in the longitudinal direction, that is, the upper end is the second sensor unit 133 It can be connected with.

Therefore, the flare gas introduced into the gas inlet 111b may be transmitted to the second sensor unit 133 through the third pipe 131, and the flare gas passed through the second sensor unit 133. May be discharged to the gas outlet 111c through the fourth pipe 132.

Here, the gas outlet 111c is disposed above the vertical surface 113 so that flare gas discharged through the gas outlet 111c does not flow into the second pressure port 113a formed on the vertical surface 113. It is preferable to be provided on the circumferential surface portion of the measured probe 110.

The second sensor unit 133 may be a known quartz oscillator gas sensor that vibrates using flare gas as a medium, measures the density of flare gas, and measures the measured value of the data. (140).

The data analysis unit 140 may receive power from the battery unit B, and may transmit the power to the first sensor unit 123 and the second sensor unit 133.

As described above, the data analysis unit 140 receives the measured data values from the first sensor unit 123 and the second sensor unit 133 to calculate and store the flow rate of flare gas, In addition, the data values can be analyzed.

The flow measurement method using the vent nozzle according to the present invention using the flow meter 100 configured as described above, without performing a hot tapping operation to puncture an existing pipe, the flow meter 100 is located at various positions where the vent nozzle is located. It is possible to install and calculate speed correction in consideration of the effect of non-uniform flow caused by a curved tube, so it provides a basic technology to monitor the flow of flare gas at various points, thereby enabling efficient management of the entire flare system. .

In addition, in the flow measurement method using a vent nozzle according to the present invention, the velocity of the flare gas is measured by a pressure calculation method that is not affected by turbulent/laminar flow according to the flow rate of the flare gas, and the velocity value of the flare gas is measured. By calculating the flow rate, it is possible to improve the accuracy of the flow rate measurement of the fluid in the pipe.

In addition, since the flow measurement method using the vent nozzle according to the present invention measures the flow rate of flare gas using the vent nozzle provided at intervals along the longitudinal direction of the pipe, it is possible to accurately grasp the gas leakage point located between the plurality of flow meters. The pressure fluctuation for each section of the pipe can be accurately identified.

In addition, the flow measurement method using the vent nozzle according to the present invention, it is possible to measure the flow rate of the flare gas with high accuracy even in a pipe having the shape of a curved tube.

So far, specific embodiments according to the present invention have been described, but various modifications are possible without departing from the scope of the present invention.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the claims described below, but also by the claims and equivalents.

S100: Flow meter insertion step S150: Speed distribution analysis step
S200: Measurement step S300: Flow calculation step
S400: analysis step 100: flow meter
110: measuring probe 120: speed measuring unit
130: density measurement unit 140: data analysis unit

Claims (9)

An insertion step of inserting a flow meter into the inside of the pipe;
A measuring step of measuring the velocity and density of flare gas using the flow meter disposed inside the pipe in the insertion step;
A calculating step of calculating a flow rate of the flare gas based on the velocity value and the density value of the flare gas measured in the measuring step; And
Includes; analysis step of analyzing the flow value of the flare gas calculated in the calculation step,
When the pipe is in the form of a curved tube or in a position affected by non-uniform flow due to the curved tube, a speed distribution analysis step of determining and correcting the flow profile of the flare gas through CFD (Computational fluid dynamics) is further included. Flow measurement method using a vent nozzle.
According to claim 1,
In the inserting step, a flow measurement method using a vent nozzle, characterized in that the flow meter is inserted into the pipe through a vent nozzle provided in the pipe.
According to claim 2,
The velocity of the flare gas measured in the measuring step is
Flow measurement method using a vent nozzle, characterized in that calculated using the pressure difference generated by the flow of the flare gas.
The method of claim 3,
The velocity of the flare gas measured in the measuring step is
After calculating the dynamic pressure from the voltage measured in the direction facing the flow direction of the flare gas and the static pressure measured at the point where the flow meter is inserted, the calculated dynamic pressure value is calculated. Flow measurement method using a vent nozzle, characterized in that calculated using the Bernoulli equation as a basis.
delete According to claim 1,
The flow meter,
A measurement probe in which a lengthwise lower end portion is inserted into the pipe through a flow path formed in the vent nozzle;
A speed measuring unit measuring a flare gas speed while connected to the measuring probe;
Density measurement unit for measuring the density of the flare gas connected to the measurement probe; And
Flow rate using a vent nozzle comprising a; data analysis unit for calculating the flow rate of the flare gas based on the value measured by the speed measurement unit and the density measurement unit, and stores and analyzes the calculated flow rate; How to measure.
The method of claim 6,
The measurement probe,
A semi-circular round surface disposed to face the flow direction of the flare gas;
A chamfer provided on the rear side of the round surface with a predetermined depth; And
A method of measuring a flow rate using a vent nozzle, comprising: a vertical surface that divides the chamfered portion and connects both ends of the round surface in the width direction to each other.
The method of claim 7,
The speed measurement unit,
A first pipe connected at one end in the longitudinal direction to a first pressure port formed on the round surface;
A second pipe having one end longitudinally connected to a second pressure port formed on the vertical surface; And
The speed of flare gas is connected to the other end of the first pipe in the longitudinal direction and the other end of the second pipe to be communicatively connected to the pressure generated in the first pipe and the pressure generated in the second pipe The first sensor unit for measuring; Flow measurement method using a vent nozzle comprising a.
The method of claim 8,
The density measurement unit,
A third pipe having one end connected in a longitudinal direction to a gas inlet formed in the round surface;
A fourth pipe to which a lengthwise one end is communicatively connected to a gas outlet formed on a circumferential surface of the measurement probe in which the chamfer is not disposed;
It is characterized in that it comprises; a second sensor part which is communicatively connected to the other end of the third pipe in the longitudinal direction and the other end of the fourth pipe and measures the density of the flare gas flowing through the third pipe; Flow measurement method using a vent nozzle.

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