JP4789666B2 - Gas pipeline monitoring equipment - Google Patents

Description

  The present invention relates to a leakage monitoring facility for a gas pipeline, and more particularly to a monitoring facility for detecting hydrogen leakage in a hydrogen gas pipeline.

  For example, in the case of city gas, a gas pipeline connects a gas manufacturing plant and a complex with a city where a gas is used and piping for the purpose of transporting purified gas. The pressure / flow rate is measured at the supply source and the supply destination, and is constantly monitored by a central monitoring facility (see, for example, Patent Document 1).

: JP 2004-138627 A

  However, when transporting hydrogen through a pipeline, the molecular weight of hydrogen is small, so it easily enters the gaps between instruments and valves, and is brittle and easily leaks from the deteriorated part of the weld. In addition, there are problems that it is difficult to detect by the flow rate and pressure monitoring method and early detection is difficult.

The present invention has been made in order to solve the problem, and is provided along the outside of a gas pipeline used for transporting a predetermined gas, and a sampling tube provided with a suction port on a side surface thereof, and the sampling tube In a gas pipeline monitoring facility that has a suction means for sucking gas through a gas and an analysis means for analyzing a component of the sucked gas, and detects leakage of a predetermined gas by the analysis means, the end of the sampling pipe The control valve provided, the discharge means for discharging the gas in the sampling pipe from the end portion, the suction means is stopped, the control valve is opened, and the discharge means is started. And an interlocking control device that discharges water.

The interlock control device of the present invention opens the control valve and discharges the gas in the sampling pipe by the discharge means, then closes the control valve, sucks the gas by the suction means, and sucks the predetermined gas. And a specifying means for specifying the monitoring point of gas leakage based on the above.

The suction port of the present invention is characterized in that the diameter is smaller than the inner diameter of the sampling tube.

  According to the present invention, a sampling pipe disposed along the outside of a gas pipeline used for transporting a predetermined gas and provided with a suction port on its side surface, and a suction means for sucking gas through the sampling pipe And an analyzing means for analyzing the components of the sucked gas, the sampling pipe can linearly collect the atmosphere around the gas pipeline, and the range for monitoring the gas pipeline is wide. Further, since the suction method is used, the leaked predetermined gas is easily carried to the analyzer and the detection time is short. Furthermore, if a monitoring measurement point is specified, the position of gas leakage can be known.

  FIG. 1 shows a system configuration of a gas pipeline and a gas pipeline monitoring facility according to the present invention. 2 is a cross section of the gas pipeline and the sampling pipe, and FIG. 3 is a slope view.

Embodiment 1
The hydrogen pipeline 30 is a pipe that transports hydrogen gas by connecting, for example, a hydrogen production source side and a hydrogen consumption destination side, and is usually buried in the ground via a protective pipe.

  The gas pipeline monitoring facility 100 mainly includes a sampling pipe 1, a detection unit 2, and an interlock control device 3. As shown in FIG. 1, the sampling tube 1 is disposed in close contact with the hydrogen pipeline 30, that is, in parallel with the hydrogen pipeline 30. The detection unit 2 includes a suction pump 21 as a suction unit, a discharge pump 22 as a discharge unit, a mass spectrometer 23 as an analysis unit, and a data conversion unit 24. The interlock control device 3 displays the gas concentration, for example, issues a gas leak alarm, or controls the opening and closing of the control valve 14 described later by the detection signal from the detection unit 2 to monitor the gas pipeline. The facility 100 is controlled.

  Next, the arrangement of the sampling tube 1 will be described.

  One end of the sampling tube 1 is connected to the suction pump 21. When the suction pump 21 is activated, the gas in the sampling tube 1 is sucked and sent to the mass spectrometer 23. Further, this end of the sampling pipe 1 is also connected to the discharge pump 22, and when the discharge pump 22 is activated, the gas in the sampling pipe 1 can be discharged from the opposite side of this end, that is, from the end of the pipe. . Control valves 12 a and 12 b are provided on the outlet sides of the suction pump 21 and the discharge pump 22, respectively, and a selection switch 13 is attached to the control valve 12. As a result, it is possible to select an operation for sucking or discharging the sampling tube 1. A control valve 14 is provided at the end of the sampling tube 1, and the interlock control device 3 controls the opening / closing operation of the control valve 14 in an interlocking manner.

  The sampling tube 1 is formed of an elongated pipe, and the inner diameter of the pipe is, for example, 10 mm. On the other hand, a plurality of suction ports 11 are provided on the side surface of the sampling tube 1, and the diameter of the suction ports 11 is smaller than the inner diameter of the sampling tube 1, for example, 1 mm. The installation interval of the suction ports 11 is set so as to coincide with the intervals of the monitoring measurement points (A point, B point, C point...) Of the hydrogen pipeline 30. For example, when the interval (A to B) between the monitoring measurement points of the hydrogen pipeline 30 is 5 m, the installation interval between the suction port 11a and the suction port 11b may be set to 5 m. In addition, the suction port 11 is placed closer to the welded portion 31 in the vicinity of the leaking portion of the hydrogen pipeline 30, for example, in the vicinity of the welded portion, the connecting portion of the instrument and valves, in this case. In addition to installing the port 11b1, the suction port 11b2 and the suction port 11b3 are provided on both sides of the suction port 11b1, for example, at an interval of 0.5 m. If it does so, the range of gas sampling will be expanded to the place where hydrogen leaks easily, and leakage of hydrogen gas can be detected earlier.

  The mass spectrometer 23 is a device for analyzing gas components, and has high accuracy and high response characteristics. In particular, hydrogen has a molecular weight of 2 and is easily distinguished from other gases. It can be detected immediately. The data converter 12 is a device that converts the detection data of the mass spectrometer 23 and transmits it to the interlock control device 3. The interlocking control device 3 has functions such as displaying and alarming the gas concentration, and controlling the suction / discharge of the pump and the control valve 14.

  Hereinafter, the operation procedure of the gas pipeline monitoring facility 100 will be described with reference to FIG.

  At all times, the control valve 12a and the control valve 12b are opened and closed, respectively, and the control valve 14 at the end of the sampling tube 1 is closed. The suction pump 21 collects the gas around the hydrogen pipeline 30 through the suction port 11, and the mass spectrometer 23 analyzes the components of the collected gas (S1).

  Hydrogen gas leaked from the welded portion 31, and the hydrogen gas was detected by the mass spectrometer 23 (S2).

  The mass spectrometer 23 sends a hydrogen gas detection signal to the interlock control device 3 via the data converter 24. The interlock control device 3 displays the concentration of hydrogen leakage and issues a preliminary alarm (S3).

  The interlock control device 3 opens the control valve 14 (S4), stops the suction pump 21, closes the control valve 12a by operating the selection switch 13, opens the control valve 12b, and activates the discharge pump 22. (S5).

  Since the discharge pump 22 is activated, the gas containing hydrogen in the sampling tube 1 is once discharged from the end of the tube (S6). In this case, since the tube diameter of the sampling tube 1 is designed to be larger than the diameter of the suction port 11, the gas in the sampling tube 1 is almost discharged from the end portion.

  After the gas in the sampling pipe 1 is discharged, that is, in the state where there is no hydrogen gas in the sampling pipe 1, the control valve 14 is closed (S7), the discharge pump 22 is stopped and the control valve 12b is closed, The control valve 12a is opened and the suction pump 22 is activated. At this time, counting of suction time is started (S8).

  When hydrogen gas is detected again in the mass spectrometer 23 (S9), the interlock control device 3 can specify the position of the suction port 11 based on the suction time and the suction speed (S10). And the monitoring measurement point corresponding to the position can be specified (S11).

  Then, the interlock control device 3 displays the position and concentration of hydrogen leakage from the hydrogen pipeline 30 and issues an alarm (S12).

  If the hydrogen gas cannot be detected again by the mass spectrometer 23, the leakage of the hydrogen gas is not determined and the monitoring operation is continued by the sampling tube 1 (S9).

  Here, the use of the two pumps (the suction pump 21 and the discharge pump 22) has been described. However, suction and discharge to the sampling pipe 1 can be realized by rotating the pump using a single pump.

  According to the first embodiment, in the hydrogen pipeline 30 used for transporting hydrogen gas, the sampling pipe 1 disposed along the outside of the hydrogen pipeline 30 and provided with the suction port 11 on the side surface thereof, The gas pipeline monitoring equipment 100 including a suction pump 21 that sucks gas through the sampling tube 1 and a mass spectrometer 23 that analyzes the components of the sucked gas detects that the mass spectrometer 23 detects hydrogen gas. Then, it can be determined that hydrogen gas is leaking from the hydrogen pipeline 30. The hydrogen pipeline 30 is divided into monitoring measurement points A, B..., The control valve 14 provided at the end of the sampling pipe 1 is opened, and the hydrogen gas in the sampling pipe 1 is discharged by the discharge pump 22. , The control valve 14 is closed, the suction pump 21 sucks hydrogen gas from the suction port 11, and the hydrogen gas leakage position (monitoring measurement point) is specified based on the suction time of the hydrogen gas. And complete monitoring of the hydrogen pipeline 30 can be realized.

  Further, the suction port 11 is densely installed in a portion where the hydrogen gas of the hydrogen pipeline 30 is likely to leak, for example, the welded portion 31. Then, the range of gas sampling is expanded around the welded portion 31, and if there is a leak of hydrogen gas, it can be detected sooner.

  Further, the mass spectrometer 23 as an analyzer has high accuracy and high response characteristics, and particularly hydrogen has a molecular weight of 2 and is easily distinguished from other gases, so even if a trace amount of hydrogen gas leaks. Can be detected.

Embodiment 2
A plurality of monitoring measurement points (A, B, C) are provided in the hydrogen pipeline 30, and each monitoring measurement point is associated with the sampling pipe 1, and the gas at each monitoring measurement point is sucked by switching the selection valve 4. (FIG. 5).

  In this case, for example, the sampling tube 1 a corresponds to the monitoring measurement point A, the sampling tube 1 b corresponds to the monitoring measurement point B, the sampling tube 1 c corresponds to the monitoring measurement point C, and the sampling tube 1 is operated by operating the selection valve 4. Collects the gas at each monitoring measurement point via the suction port 11 and analyzes the gas in the mass spectrometer 23. When hydrogen gas leaks from the hydrogen pipeline 30, the interlock control device 3 can determine the monitoring measurement point by judging the sampling pipe 1 of the sent hydrogen gas.

  According to the second embodiment, the two pumps and the control valve 14 of the first embodiment can be omitted. When hydrogen gas leaks from the hydrogen pipeline 30, the interlock control device 3 in the gas pipeline monitoring facility 200 determines the location (monitoring measurement point) of the gas leak by judging the sampling pipe 1 of the sent hydrogen gas. And complete monitoring of the hydrogen pipeline 30 can be realized.

  In the first embodiment and the second embodiment, the hydrogen gas pipeline is described as an example. However, the present invention is not limited to the hydrogen gas, and other flammable materials can be used by utilizing the characteristics of the mass spectrometer that can analyze the multi-component gas. Gas leaks in the pipeline of sexual or toxic gases can also be monitored.

It is explanatory drawing of the gas pipeline monitoring equipment 100 concerning Embodiment 1. FIG. 1 is a cross-sectional view of a hydrogen pipeline 30 and a sampling pipe 1 according to Embodiment 1. FIG. 2 is a perspective view of a hydrogen pipeline 30 and a sampling pipe 1 according to Embodiment 1. FIG. 3 is a flowchart of an operation procedure according to the first embodiment. It is explanatory drawing of the gas pipeline monitoring equipment 200 concerning Embodiment 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Gas pipeline monitoring equipment 1 Sampling pipe 2 Detection part 3 Interlocking control apparatus 4 Selection valve 11 Suction port 13 Selection switch 14 Control valve 21 Suction pump 22 Discharge pump 23 Mass spectrometer 24 Data conversion part 30 Hydrogen pipeline 31 Welding part A, B, C Monitoring measurement points

Claims (3)

A sampling pipe disposed along the outside of a gas pipeline used for transporting a predetermined gas and provided with a suction port on a side surface thereof, a suction means for sucking the gas through the sampling pipe, and the sucked gas And a gas pipeline monitoring facility for detecting leakage of a predetermined gas by the analyzing means.
A control valve provided at the end of the sampling tube;
Discharging means for discharging the gas in the sampling pipe from the end portion;
An interlocking control device for stopping the suction means, opening the control valve, and starting the discharge means to discharge the gas in the sampling pipe by the discharge means ; Gas pipeline monitoring equipment. The interlock control device opens the control valve and discharges the gas in the sampling pipe by the discharge means, then closes the control valve and sucks the gas by the suction means, and at a predetermined gas suction time. The gas pipeline monitoring equipment according to claim 1, further comprising: a specifying unit that specifies a monitoring point for monitoring gas leakage. The gas pipeline monitoring facility according to claim 1 or 2 , wherein a diameter of the suction port is smaller than an inner diameter of the sampling pipe .