JP2005127907A - Gas detection system and compound gas detection system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect gas in a real time in a plurality of measuring points, to transmit a measured data in a real time, and to monitor and control centralizingly the measured data in the plurality of measuring points. <P>SOLUTION: The gases from the plurality of measuring points 10, 20, 30 in a remote site are transferred to detectors by gas detectors 110, 120, a piping switching device 130 and a distributor 140 in an APCI-MS (atmospheric pressure chemical ionization mass spectrometer), and the gasses are detected in the real time. The data obtained in the detectors are transmitted to a communication control computer 103 and a remote monitoring station 150 via a communication line, so as to allow the centralized monitoring and control in the remote site. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a gas detection system and a composite gas detection system, and more particularly, to a gas detection system and a composite gas detection system suitable for use in real-time gas detection at a plurality of measurement points.

  2. Description of the Related Art Conventionally, a gas detection system that detects the presence of a certain type of gas that is harmful to a human body in a closed space such as the atmosphere or indoors is known. This type of prior art system is a gas detector that draws gas together with the atmosphere to concentrate, extract, and analyze. When gas detection is to be performed at a plurality of measurement points, one detector is transported and measurement is performed sequentially. Further, in the system according to the prior art, the detector to be used is an individual device, and the operator needs to operate the detector to perform analysis work, and manually write the result as data.

As a conventional technique related to the gas detection system as described above, for example, a technique described in Non-Patent Document 1 or the like is known.
Evaluation of alternative index properties of chlorobenzenes using an automatic dioxin precursor analyzer Proceedings of the 12th Annual Meeting of the Waste Society 2001

  The gas detection system according to the prior art takes a long time to detect the gas, and it is difficult to measure in real time. In addition, when gas detection is performed at multiple measurement points, a single detector is transported and sequentially measured. Therefore, there is a problem that it takes a long time to monitor all measurement points. This problem can be solved by installing detectors at multiple measurement points and shortening the monitoring cycle. However, it is necessary to prepare multiple expensive detectors, which increases the system cost. This causes the problem.

  Furthermore, the system according to the prior art requires the use of individual devices as gas detectors, and even if multiple gas detectors can be installed, the operator operates each detector to perform analysis work. It was necessary to transcribe the results manually as data, which not only took time, but there was a risk of transcription errors, making it difficult to convey accurate information immediately. Have.

  The object of the present invention is to solve the above-mentioned problems of the prior art, enable detection of gas at a plurality of measurement points in real time, transmit measurement data in real time, and measure data at a plurality of points. It is an object of the present invention to provide a gas detection system and a composite gas detection system that can monitor and control the gas centrally.

  According to the present invention, the object is to provide a gas detection system for detecting the presence and concentration of gas in a gas to be inspected at a plurality of measurement points, a pipe switching device, a gas detector, and the plurality of measurement points. And an inlet pipe connecting the pipe switching device, and the pipe switching device sequentially switches the inlet pipe from the gas measurement point installed at each of a plurality of points, and the gas to be inspected from the one inlet pipe Is achieved by introducing the gas detector into the gas detector.

  In addition, in the composite gas detection system configured by a plurality of gas detection systems, the object includes a pipe switching device, a gas detector, and a plurality of measurement points and an introduction pipe that connects the pipe switching device. The pipe switching device sequentially switches the introduction pipes from the gas measurement points installed at each of the plurality of points, and introduces the gas to be inspected from the one introduction pipe to the gas detector. A plurality of gas detection systems for detecting the presence and concentration of the gas in the gas to be inspected at the measurement point are distributed, and at least one of the gas detection systems includes a remote monitoring station, Receiving a detection result from each of the gas detectors of the plurality of gas detection systems via a communication line, and detecting the plurality of gas detection systems. It is accomplished by monitoring the detection result of the gas in the inspection gas at each of the plurality of measurement points in the system.

  According to the present invention, gas can be detected at a plurality of measurement points in real time, and measurement data at a plurality of points can be monitored and controlled centrally.

  Hereinafter, an embodiment of a gas detection system according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a configuration of a composite gas detection system including a plurality of gas detection systems according to an embodiment of the present invention. In FIG. 1, 10, 20, 30 are measurement points, 11, 21, 31, 50, 90, 94 are introduction pipes, 40, 80, 81 are exhaust pipes, 100, 200, 300 are on-site monitoring stations, 101, 151 Is a distribution board, 102 and 152 are hubs, 103 is a communication control computer, 104 and 154 are LAN cables, 105 and 155 are uninterruptible power supplies, 106 is an air conditioner, 110 and 120 are gas detectors, and 130 is a pipe switch 140, a distribution device, 150 is a remote monitoring station, 153 is a computer, 160, 260, 360 are optical cables, 1000, 2000, 3000 are gas detection systems.

  The composite gas detection system according to the embodiment of the present invention includes a plurality of gas detection systems 1000, 2000, and 3000. Each of the gas detection systems 1000, 2000, and 3000 includes at least on-site monitoring stations 100, 200, and 300 and a pipe switching device 130. In the example shown in FIG. 1, the gas detection system 1000 includes a remote monitoring station 150 in addition to the above, and this remote monitoring station 150 is connected to the own system 1000 and other devices via optical cables 160, 260, and 360. Connected to on-site monitoring stations 200, 300 of the system. Hereinafter, the configuration of the gas detection system will be described using the gas detection system 1000 as an example.

  The gas detection system 1000 includes a remote monitoring station 150, an on-site monitoring station 100, and a pipe switching unit 130. These may be installed in one building, but the remote monitoring station 150 is installed in one building, and the on-site monitoring station 100 and the pipe switching unit 130 are installed in another room in another building. You may make it do. In the illustrated example, it is assumed that the on-site monitoring station 100 is installed in a room in another building, and an air conditioner 106 is provided for the protection of equipment and the worker's environment.

  A plurality of introduction pipes 11, 21, and 31 are connected to the pipe switching unit 130, and the atmosphere or the room that may contain toxic gas or the like taken in from a plurality of gas measurement points 10, 20, and 30. The air present in the closed space is introduced. The gas measurement points 10, 20, and 30 are installed at a plurality of locations in a large space that is installed on the ground and sealed, for example. , Let's say gas). The gas detection system according to the embodiment of the present invention detects the presence or absence of a target gas at these measurement points, and detects the concentration when the gas is detected.

  The pipe switching device 130 has a function of selecting one pipe from the introduction pipes 11, 21, and 31, guiding gas from the selected pipe to the introduction pipe 50, and guiding other pipe gases to the exhaust pipe 40. A method for realizing this function will be described later in detail with reference to FIG. The gas guided to the introduction pipe 50 is guided to the on-site monitoring station 100. The on-site monitoring station is installed relatively close to the gas measurement points 10, 20, and 30. The introduced gas 140 has a function of selectively guiding the gas guided to the introduction pipe 50 to the gas detector 110 via the introduction pipe 90 or the gas detector 120 via the introduction pipe 94. The gas for which gas detection has been completed is discharged to the outside through the exhaust pipes 80 and 81, or in the case of toxic gas, it is discharged through a gas removal device such as a filter (not shown). A method for realizing the function of the distribution device will be described later in detail with reference to FIG.

  Detectors 110 and 120 installed in the on-site monitoring station 100 measure the gas concentration of the detection target contained in the introduced gas, and use, for example, APCI-MS (atmospheric pressure chemical ionization mass spectrometer). To do. This APCI-MS has the characteristic that gas can be continuously monitored, and is optimal for use in the present invention. However, the present invention uses any type of detector. Also good. The two detectors 110 and 120 are used so that when one of them becomes out of order or maintenance is necessary, the other detector is used without interrupting the gas detection. Can be done continuously. Two detectors may be provided for detecting different gases, and measurement may be performed simultaneously.

  In general, the gas detector performs ionization of the gas to be detected inside, but at that time, it is necessary to ionize positively or negatively depending on the type of gas to be detected. The gas detector used in the embodiment of the present invention is configured so that the polarity of an ionization power source for gas ionization can be switched between positive and negative. Thereby, various types of gas can be detected by a single detector.

  The gas detection results by the detectors 110 and 120 are transmitted to the communication control computer 103 via the LAN cable 104 and subjected to data processing. The communication control computer 103 also performs monitoring of data of two detectors and control of starting and stopping of these detectors. Data processed by the communication control computer 103 is transmitted to the remote monitoring station 150 through the optical cable 160 by the hub 102 via the LAN cable 104. Metal cables can be used instead of optical cables.

  The data sent via the optical cable 160 is transmitted to the remote monitoring computer 153 via the hub 152 and the LAN cable 154 at the remote monitoring station 150, and the detection information of the gas measurement point is displayed on the display screen of this computer. Remote and real-time monitoring is possible. The remote monitoring station 150 is configured such that gas detection information is transmitted from the on-site monitoring stations 200 and 300 installed at different points through optical cables 260 and 360 so that the gas detection information at a plurality of locations can be centrally monitored. In order to ensure continuous monitoring, the on-site monitoring station 100 and the remote monitoring station 150 are provided with uninterruptible power supplies 105 and 155 in addition to the distribution boards 101 and 151 that supply power during normal operation. .

  In the embodiment of the present invention shown in FIG. 1, an example is given in which gas is collected from three measurement points at one on-site monitoring station. However, the number of measurement points may be increased as necessary. The number of monitoring stations is not three but can be increased according to the number and scale of facilities to be detected.

  The example described in FIG. 1 has been described on the assumption that two detectors are provided with one pipe switching device, but the present invention is provided with a pipe switching device provided in one detector, and these are integrated. It is possible to detect gas at a plurality of measurement points by installing only one such detector.

  FIG. 2 is a diagram illustrating the configuration of the pipe switching device 130 and the distribution device 140. Next, the configuration of the pipe and the gas flow will be described with reference to FIG. 2, 12, 22, 32, 113, 123 are pumps, 13, 23, 33 are flow control valves, 14, 24, 34, 92, 96 are reagent inlets, 16, 26, 36 are three-way valves, 61 63, 71, 74, 91 and 95 are gate valves, 64 is a compressor, 72, 75, 112 and 122 are flow meters, 77 is a controller, 79 is an exhaust blower, 114 and 124 are exhaust ports, Reference numerals are pipes other than those shown in FIG.

  In FIG. 2, paying attention to the measurement point 10, the vacuum pump 12 sucks the gas from the measurement point 10 and transfers the gas through the introduction pipe 11. As will be described later, the transferred gas is adjusted to a flow rate required for the detector, and is introduced to the three-way valve 16 of the pipe switching device 130 via the introduction pipe 15. A reagent inlet 14 is branched and attached to the introduction pipe 15. By injecting the reagent from the reagent inlet 14, it is possible to quantitatively grasp whether or not the gas transferred through the introduction pipe described below has reached the gas detector 110 or the gas detector 120. . The three-way valve 16 has a function of branching the gas transferred through the introduction pipe 15 to the introduction pipe 18 or the exhaust pipe 17. When the transfer gas is transferred to the introduction pipe 18, the gas is guided to the gate valve 61 through the introduction pipes 50 and 60. When the transfer gas is guided to the exhaust pipe 17, the gas is discharged through the exhaust pipe 40.

  The pipes from the measurement points 20 and 30 are configured in the same manner as described above, and the gas sucked from the measurement point 20 by the vacuum pump 22 passes through the introduction pipes 21 and 25 to the introduction pipe 28 or the exhaust pipe 27 by the three-way valve 26. Led. Further, the gas sucked from the measurement point 30 by the vacuum pump 32 is guided to the introduction pipe 38 or the exhaust pipe 37 by the three-way valve 36 through the introduction pipes 31 and 35. Then, by controlling the three three-way valves 16, 26, and 36 as described later, one pipe gas is selected from the gas sucked from the measurement points 10 to 30 and led to the distribution device 140 through the introduction pipe 50. Will be.

  The gate valve 61 in the distribution device 140 is normally opened, the gate valve 63 of the pipe 62 is closed, and the transferred gas is guided to the introduction pipes 70 and 73. In addition, when the gate valve 61 is closed and the gate valve 63 is opened, the compressed air from the compressor 64 sends air into the introduction pipes 62, 50, 18, 15, and 11, thereby cleaning the pipes. It can be carried out.

  The gas that has passed through the normally open gate valve 61 is branched into an introduction pipe 70 and an exhaust pipe 73. The gas guided to the introduction pipe 70 is transferred to the detector 110 or the detector 120 side through the normally opened gate valve 71. On the other hand, the gas guided to the exhaust pipe 73 is guided to a path for exhausting from the exhaust pipe 81 by the exhaust blower 79 via the gate valve 74, the flow meter 75, and the exhaust pipe 78. The gas guided to the introduction pipe 70 branches into the introduction pipe 90 and the introduction pipe 94 via the gate valve 71 and the flow meter 72. The introduction pipe 90 guides the gas to the detector 110. By opening the gate valve 91 and closing the gate valve 95, the inlet pipe 90 is led to the inlet pipe 111 of the detector 110 through the inlet pipe 93, and the flow meter. 112, and exhausted to the exhaust port 14 by the vacuum pump 113. The exhausted gas passes from the exhaust port 114 through the exhaust pipe 80 and is exhausted from the exhaust pipe 81 by the exhaust blower 79 described above. On the other hand, by closing the gate valve 91 and opening the gate valve 95, the gas can be guided to the introduction pipe 94 and transferred to the detector 120. Details are the same as in the case of the detector 110 described above, and a description thereof will be omitted. Although not shown, the main bodies of the analysis units of the detectors 110 and 120 are provided between the flow meter 112 and the vacuum pump 113 and between the flow meter 122 and the vacuum pump 123.

  As described above, the gas transferred from the introduction pipe 50 is distributed to the gas introduced into the detector and the gas led to the exhaust pipe, and the gas led to the detector 110 and the detector 120 is selectively distributed. Can do.

  The introduction pipe 93 is provided with a branched reagent inlet 92, and the detection performance of the detector 110 can be evaluated by injecting the reagent from the reagent inlet 92.

  In order to maintain the sensitivity of the detector, it is necessary to keep the gas flow rate constant (approximately 0.5 liters per minute). Next, a control method for this purpose will be described.

  The gas sucked from the measurement point 10 passes through the introduction pipes 15, 18, 50, 60, 70, and the flow rate before being led to the detector by the flow meters 72, 75 is measured. The flow rate is adjusted by the flow control valve 13 so as to be 0.5 liters per minute. In the case of the measurement point 20 and the measurement point 30, the flow rate is adjusted by the flow control valves 23 and 33 as described above. Normally, once the introduction pipe is laid, the pipe length is constant, and the adjustment of the flow control valves 13, 23 and 33 described above may be semi-fixed to the initial set state. Since readjustment is required due to changes in environmental conditions, the automatic adjustment function is a function necessary for realizing continuous monitoring. Also, when the introduction pipe is made flexible, for example, when the measurement point is moved using a flexible introduction pipe, the pressure loss of the gas in the pipe changes depending on the pipe length. Each time the length is changed, it is necessary to adjust the flow rate. Therefore, in the embodiment of the present invention, the flow rate information 76 from the flow meter 75 is taken into the controller 77, and the control signals 19, 29, 39 for feedback are generated in the flow control valves 13, 23, 33 to The control is made so that the flow rate at the detector inlet is always appropriate by returning to the valves 13, 23, and 33.

  In the embodiment of the present invention, the gas having passed through the gate valve 61 described above is branched into the introduction pipe 70 and the exhaust pipe 73, and the gas guided to the introduction pipe 70 is transferred to the detector 110 or the detector 120 side. The gas led to the exhaust pipe 73 is exhausted from the exhaust pipe 81. However, the flow meter 75 described above is provided in the exhaust side pipe, and the flow control valves 13, 23, 33 are controlled by the exhaust flow rate. To control. In the embodiment of the present invention, the exhaust flow rate is set to 4.5 liters per minute, and the flow rate to the detector is set to 0.5 liters per minute as described above. For this reason, the flow control valves 13, 23, 33 are controlled so as to take in 5.0 liters of gas per minute. Of course, the flow control of the flow control valves 13, 23, 33 may be performed not by the information on the exhaust flow meter 75 but by the information on the flow meter 72 on the detector side, but the gas flow on the exhaust side is detected. The gas flow rate on the detector side can be controlled more accurately than the opposite case by controlling the flow rate of the gas to be taken in by making it somewhat larger than the gas flow rate on the machine side and by the flow rate on the exhaust side. This is what the present inventors have found.

  In the embodiment of the present invention shown in FIG. 1 and FIG. 2 described above, the pipe, valve, flow meter, etc. for transferring the gas have a predetermined temperature using an electric heater or the like in order to prevent the gas from adsorbing. (In the embodiment of the present invention, it is desirable to maintain at 145 ° C. ± 5 ° C.). In the above description, compressed air is flowed for cleaning pipes, valves, flow meters, etc., but these cleanings are performed at a higher temperature than the above for a certain period of time. In the embodiment of the invention, it can also be performed at 195 ° C. ± 5 ° C.

  FIG. 3 is a timing chart for explaining an example of a gas switching procedure in the pipe switching device 130. Next, this will be described.

  The example shown in FIG. 3A shows an example in which the introduction pipes are sequentially switched, and the horizontal axis of the figure indicates time. Now, it is assumed that all the three-way valves are in a closed state, and at time t1, the three-way valve 16 of the introduction pipe 15 is controlled to be opened from the closed state. As a result, the intake gas from the measurement point 10 is guided to the detector through the piping path described above. Next, when the three-way valve 16 is closed at time t2 and the three-way valve 26 of the introduction pipe 25 is opened from the closed time t3, the suction gas from the measurement point 20 is guided to the detector. Further, when the three-way valve 26 is closed at time t4 and the three-way valve 36 of the introduction pipe 35 is opened at time t5, the suction gas from the measurement point 30 is guided to the detector. When the three-way valve 36 is closed at time t6 and the three-way valve 16 is opened again at time t7, the suction gas from the measurement point 10 is guided to the detector.

  By repeatedly controlling the switching of the introduction pipe as described above, the gas at the measurement points 10, 20, and 30 can be sequentially guided to the detector to detect the gas.

  The example shown in FIG. 3B shows another example in the case of sequentially switching the introduction pipe. In this example, all of the three-way valves 16, 26, 36 of the introduction pipes 15, 25, 35 are initially opened. In this state, the gases from the measurement points 10, 20, and 30 are mixed and guided to the gas detector. If the detector does not detect the presence of gas in this state, this state is maintained and detection continues. Assume that the presence of some gas is detected at time t0. In this case, at the same time as the presence of gas is detected, control is performed so that all three-way valves are once closed. Then, sequentially from time t1, the three-way valve 16 of the introduction pipe 15 is opened and the gas is detected. Next, at time t2, the three-way valve 16 is closed, and at the time t3, the three-way valve 26 of the introduction pipe 25 is opened and the gas is opened. Detection is performed. Next, the three-way valve 26 is closed at time t4, and the gas is detected by opening the three-way valve 36 of the introduction pipe 35 at time t5. In this way, in the example shown in FIG. 3B, gas detection is usually performed for the entire introduction pipe, and when the gas is detected, gas detection is performed again for each pipe. Unless the detection is made, it is not necessary to switch the three-way valve, and the life of the device can be set longer.

  For example, in the example shown in FIG. 3A, the three-way valve opening time (from time t1 to time t2, time t3 to t4, time from t5 to t6 in the figure) is 2 minutes, and the three-way valve in the middle If the time of the closed state (from time t2 to time t3, from time t4 to time t5, and from time t6 to time t7) is 0, in order to detect the gas at the measurement points 10, 20, and 30, Each three-way valve opens and closes once every 6 minutes. If the opening and closing of the three-way valve is counted once, the opening / closing frequency of one three-way valve is 20 times per hour, 480 times per day, 175200 times per year, and the normal operating life of the three-way valve is 100,000 times If calculated from the above, replacement will be required in about half a year, and maintenance work and costs will be required. On the other hand, in the case shown in FIG. 3 (b), all three-way valves are normally opened, and switching is performed sequentially only in the case of gas detection. Therefore, if the presence of gas is detected once a day, One three-way valve can be opened and closed twice a day, 730 times a year, which is advantageous in terms of ensuring the life of the valve, and can be maintenance-free and reduce maintenance costs.

  FIG. 4 is a diagram for explaining an example in which the configuration of the gas flow path including the introduction pipe is doubled. Next, this will be described. Of the reference numerals shown in FIG. 4, the part denoted by reference numeral 400 is a part called a 1b system provided for duplication. From the measurement points 10, 20, 30, the introduction pipe and the pipe switching device 130, the distribution device The point that gas is transferred to the detectors 110 and 120 via 140 is the same as that described with reference to FIG.

  In FIG. 4, the gas sucked from the measurement point 10 is led from the introduction pipe 11 shown as the 1a system through the gate valve 13 to the three-way valve 16 in the pipe switching device 130. When the three-way valve is open, the gas is guided to the distribution device 140 by the introduction pipe 50 and is guided to the detector 110 or the detector 120 as described in FIG. Here, if gas is adsorbed to the 1a system pipe, valve, or flow meter, or if impurities contained in the gas sucked from the measurement point are attached, the gas emitted from these will be an interfering gas, which will hinder detection. Therefore, it is necessary to remove (clean) these contaminants according to the amount of interfering gas. As described above, the cleaning method can be removed by increasing the evaporation rate of adhering contaminants by raising the temperature from 30 ° C. to 50 ° C. from the normal piping temperature. However, since the gas cannot be detected during the cleaning of the introduction pipe until impurities are removed, the introduction pipe and the like are duplicated to compensate for this drawback.

  In FIG. 4, when cleaning a 1a system pipe consisting of the inlet pipe 11, the gate valve 13, the three-way valve 16, and the inlet pipes 50, 70, 90, the gate valve 13 is closed, the gate valve 411 is opened, and the measurement point The gas sucked from the gas is introduced to the detector 110 or the detector 120 through the introduction pipe 411, the gate valve 413, the three-way valve 416, and the introduction pipes 450, 470, and 490. As described above, the piping of the 1a system is set to a cleaning temperature 30 ° C. to 50 ° C. higher than the normal setting temperature, and the piping of the piping 1b system is set to the normal setting temperature, so that one piping system is being cleaned. Even if it exists, gas detection can be continued by using the other piping system. For the gas sucked from the measurement point 20, even when the introduction pipe 21, the gate valve 23, and the three-way valve 26 are being cleaned by closing the gate valve 23 and opening the gate valve 421, The gate valve 423 and the three-way valve 426 can be used to transfer the gas at the measurement point 20 to the detector. Moreover, since it is the same also about the measurement point 30, description is abbreviate | omitted.

  In the above description, the introduction pipe is cleaned by setting the temperature of the pipe to a higher temperature than usual. However, as shown in FIG. 2, the cleaning is the pipe that cleans the compressed air from the compressor 64. It can also be done by sending it to the system. In this case, it is necessary to configure the flow path of the compressed air so as not to affect the other system in operation, and although not shown in the figure, a relief valve or a stop is provided at a required location on the piping path. A valve is provided. In addition, the introduction pipe can be cleaned by holding the temperature of the pipe at a temperature higher than usual for a certain period of time and then sending the compressed air to the pipe system for cleaning. In this case, more efficient cleaning is performed. be able to.

  In the embodiment of the present invention, as described above, by duplexing the piping system, even if one piping system is being cleaned, the gas from each measurement point is sucked into the detector by the other piping system. Therefore, it is possible to continuously monitor the gas detection without interruption.

  FIG. 5 is a diagram showing a display example of detection information at the remote monitoring station, which will be described next.

  As shown in FIG. 5, the screen for displaying detection information includes a common display unit and a measurement result display unit. In the illustrated example, the common display section shows that measurement is currently being performed in “Remote Mode”. Then, this common display section changes the display color from green to red to notify that the presence of gas has been detected, and to notify that an abnormality in piping temperature, an abnormality in flow rate, etc. has occurred. "Equipment Alarms" and a display area of "Normal" notifying that gas is not detected are provided.

In the measurement result display section, the display form of the measurement result is displayed at the top, and in the example shown in the figure, the measurement result is indicated by “Bar Graph”, and the pipe No. and the chemical to be detected are displayed at the next stage. The maximum value and minimum value of the agent (gas name) and detection intensity scale are displayed. In the illustrated example, “1” as the piping No. corresponds to the example of FIG. 1, for example, the number assigned to the gas measurement point 10 is “HD” (Mustard gas) as the chemical agent, “1 × 10 ⁻¹⁰ ” and “1 × 10 ⁻¹⁴ ” are displayed as the maximum value and the minimum value. The next stage is a window for displaying the detection result, which consists of a graph itself and a part for explaining it. The illustrated example shows the average “Average” of the analysis results, the scale of the graph is “LOG Scale”, and the background “BG”, “threshold 1”, “threshold 2” in each graph It shows that it shows the position of intensity, and the measurement result is displayed by “Bar Graph”.

In the illustrated example, the detection intensity corresponding to the mass of the detected substance peculiar to the mustard gas is shown as the detection result of the mustard gas. The background “BG” in this graph is the upper limit of the detection result due to the gas adhering to the piping, etc., and this background “BG” shows the detection result without including the gas to be detected. When approaching the level, it indicates that the incoming piping must be cleaned. The “threshold value 2” indicates a level in which if there is a gas containing this strength, there is no problem even if a person stays in the atmosphere for 8 hours, but if it is exceeded, it is dangerous. Incidentally, in the case of mustard gas, this value is 0.003 mg / m ³ , and in the embodiment of the present invention, the level of 1/3 is displayed as “threshold 1”.

  At the bottom of the display screen, “Detail” for further detailing the intensity scale, “Print” for performing printing, and gas detection intensity on the time axis used in the embodiment of the present invention Each button of “Back” for displaying the graph is provided. In addition, the shape of the graph displaying the detection intensity can be arbitrarily set.

  According to the embodiment of the present invention described above, by using an APCI-MS (atmospheric pressure chemical ionization mass spectrometer) as a detector, taking advantage of the continuous monitoring characteristics of this detector, the introduction pipe and the pipe switching device can be changed. By adding, it becomes possible to transfer gas from a plurality of measurement points in a remote place and monitor the gas in real time. In addition, since data from a plurality of detection systems can be transmitted, monitoring and control can be performed by a single computer. In addition, it is possible to always detect gas with high accuracy by cleaning the pipes in a timely manner. Furthermore, by using a redundant configuration of the detector and piping system, monitoring can be performed even during equipment maintenance or failure. It is possible to perform continuous gas monitoring without stopping the operation.

  The above-described embodiments of the present invention have been described by taking the mustard gas as an example of the gas to be detected. However, the present invention can also be applied to the case of detecting a gas such as sarin, soman, and leucite.

It is a figure which shows the structure of the compound gas detection system provided with two or more gas detection systems by one Embodiment of this invention. It is a figure explaining the structure of the piping switching apparatus 130 and the distribution apparatus 140. FIG. 4 is a timing chart for explaining an example of a gas switching procedure in a pipe switching device 130. It is a figure explaining the example at the time of duplicating the structure of the gas flow path containing introduction piping. It is a figure which shows the example of a display of the detection information in a remote monitoring station.

Explanation of symbols

10, 20, 30 Measuring points 11, 21, 31, 50, 90, 94 Introducing pipes 12, 22, 32, 113, 123 Pumps 13, 23, 33 Flow control valves 14, 24, 34, 92, 96 Reagent inlet 16, 26, 36 Three-way valve 40, 80, 81 Exhaust piping 61, 63, 71, 74, 91, 95 Gate valve 64 Compressor 72, 75, 112, 122 Flow meter 77 Controller 79 Exhaust blower 100, 200, 300 On-site Monitoring station 101, 151 Distribution board 102, 152 Hub 103 Communication control computer 104, 154 LAN cable 105, 155 Uninterruptible power supply 106 Air conditioner 110, 120 Gas detector 114, 124 Exhaust port 130 Pipe switching device 140 Distribution device 150 Remote monitoring station 153 Computer 160, 260 360 optical cable 1000, 2000, and 3000 gas detection system

Claims (16)

  In a gas detection system that detects the presence and concentration of gas in a gas to be inspected at a plurality of measurement points, a pipe switching device, a gas detector, and the plurality of measurement points and the pipe switching device are connected. The pipe switching device is configured to sequentially switch the introduction pipes from the gas measurement points installed at each of a plurality of points, and introduce the gas to be inspected from the one introduction pipe to the gas detector. A gas detection system.   The gas detection system according to claim 1, wherein two gas detectors are provided to form a redundant configuration.   The gas detection system according to claim 1, wherein two gas detectors are provided, and each detector detects a different kind of gas.   The gas detection system according to claim 1, wherein the plurality of measurement points are installed at different remote points.   The gas detection system according to claim 1, wherein the introduction pipe is heated and held at a predetermined temperature.   The pipe switching device is characterized in that at the beginning of measurement, the inspection gas from all of the plurality of measurement points is introduced into the detector, and once the target gas is detected, the introduction pipe is sequentially switched. The gas detection system according to claim 1.   The gas detection system according to claim 1, wherein the introduction pipe is heated to a high temperature, or compressed air is sent to remove gas and impurities adsorbed on the pipe.   The gas detection system according to claim 1, wherein the introduction pipe is configured in a double system.   The gas detection system according to claim 1, wherein a flow rate of a gas to be inspected to the introduction pipe is controlled.   The gas to be inspected into the introduction pipe is branched into the one to be introduced into the inspection machine and the one to be exhausted before being introduced into the inspection machine, and the flow rate of the gas to be inspected into the introduction pipe is The gas detection system according to claim 9, wherein the gas detection system is controlled based on a flow rate of the exhausted gas.   The gas detection system according to claim 1, wherein the pipe switching device is built in the gas detector.   The gas detection system according to claim 1, wherein the gas detector is configured to be capable of switching a polarity of an ionization power source of a gas included in the gas detector between positive and negative.   A remote monitoring station, wherein the detection results from the gas detector are sent to the remote monitoring station via a communication line, and the detection results of the gas in the gas to be inspected at the plurality of measurement points are monitored. The gas detection system according to claim 1, wherein:   14. The gas detection system according to claim 13, wherein the remote monitoring station displays a gas concentration as a detection result as a level.   A pipe switching device, a gas detector, a plurality of measurement points and an introduction pipe for connecting the pipe switching device, wherein the pipe switching device is configured to introduce an introduction pipe from a gas measurement point installed at each of a plurality of points. Gas detection for detecting the presence and concentration of the gas in the gas to be inspected at the plurality of measurement points by sequentially switching the gas and introducing the gas to be inspected from the one introduction pipe to the gas detector. A plurality of systems are distributed, and at least one of the gas detection systems includes a remote monitoring station, and the remote monitoring station communicates detection results from the gas detectors of each of the plurality of gas detection systems. Receiving through a line, and monitoring the detection result of the gas in the gas to be inspected at each of the plurality of measurement points of the plurality of gas detection systems. The composite gas detection system and butterflies. 16. The composite gas detection system according to claim 15, wherein the remote monitoring station displays a gas concentration as a detection result as a level.

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