JP7634483B2 - Analytical device and analytical system - Google Patents

Description

The present invention relates to an analytical device and an analytical system for analyzing a measurement target gas contained in a sample gas.

Conventionally, there is known an analyzer that irradiates a sample gas with a measurement light and analyzes the sample gas based on the intensity of the measurement light absorbed by the sample gas contained in the sample gas. In this analyzer, the sample gas is filled into a predetermined cell, and analysis is performed based on the intensity of the measurement light that passes through the cell. In this analyzer, the surrounding environment other than the inside of the cell (particularly, the propagation path of the measurement light other than the inside of the cell) is generally filled with a gas (hereinafter referred to as a "purge gas") that does not contain the sample gas and gas that affects the measurement light.
Analytical devices are also known that analyze a target gas based on a comparison between the intensity of measurement light that has passed through a sample gas and the intensity of measurement light that has passed through a gas that does not contain the target gas (called a reference gas).

In the above analytical device, a purge gas that does not contain the gas to be measured is supplied, for example, from a cylinder. On the other hand, a reference gas is generated, for example, by passing air or the like through a substance that can remove the gas to be measured. As a specific example of the latter, in a measurement device that uses carbon dioxide contained in the atmosphere as the gas to be measured, there is a method of generating a reference gas by passing a sample gas (air) through a carbon dioxide adsorbent such as zeolite and a substance that adsorbs polar substances such as silica gel (see, for example, Patent Document 1).

JP 2016-14658 A

When using a method in which the purge gas is supplied from a cylinder to purge an analyzer with purge gas, the cylinder must be replaced frequently. This is because a large amount of purge gas is generally required to purge the environment surrounding the analyzer so that it is free of the gas to be measured (or has a sufficiently low concentration that it does not affect the measurement). Frequent replacement of cylinders increases the burden on the user.

On the other hand, when an analysis using a reference gas is performed using a method in which a gas to be measured is removed from the atmosphere or the like to generate a reference gas, the adsorbent must be replaced frequently, which increases the burden on users.
In addition, as described in Patent Document 1, there is a method of reducing the frequency of adsorbent replacement by placing an adsorbent in each of multiple gas lines and generating a reference gas by switching the gas lines, but in this case the device configuration and device control become complicated.

Furthermore, when zeolite or silica gel is used as an adsorbent, a heating device such as a heater must be provided to remove the adsorbed components (carbon dioxide, moisture) from the zeolite or silica gel, which also complicates the device configuration.

The object of the present invention is to enable an analytical device that analyzes a gas to be measured to supply gases that do not contain the gas to be measured, such as purge gas and reference gas, without increasing the burden on the user.

In the following, several aspects will be described as means for solving the problems. These aspects can be arbitrarily combined as necessary.
An analytical device according to one aspect of the present invention is a device for analyzing a measurement target gas. The analytical device includes a filling section, an irradiation section, a propagation section, and a measurement target removal section. The filling section is filled with a sample gas including a measurement target gas. The irradiation section irradiates measurement light toward the filling section. The propagation section is provided between the filling section and the irradiation section, and forms a propagation space through which the measurement light propagates. The measurement target removal section has a gas separation membrane that removes the measurement target gas from the gas and generates a purge gas for purging the propagation space.
In the above-mentioned analytical device, the purge gas for purging the propagation space through which the measurement light propagates until it reaches the filling section is generated by the measurement target removal section having a gas separation membrane. This eliminates the need for tasks that increase the burden on the user, such as frequent replacement of cylinders for supplying purge gas. In other words, it is possible to generate and supply purge gas without increasing the burden on the user.

The analysis device further includes a detection unit and a first determination unit. The detection unit detects the measurement light that has passed through the propagation space purged by the purge gas. The first determination unit determines deterioration of the measurement target removal unit based on the intensity of the measurement light absorbed by a gas that affects the measurement target gas and the measurement light by passing through the propagation space.
This makes it possible to easily determine the deterioration state of the measurement target removal unit by a method similar to that for analyzing the measurement target gas.

The analytical device further includes a second determination unit that determines deterioration of the measurement target removal unit based on the pressure or flow rate of the gas supplied to the measurement target removal unit.
This makes it possible to determine whether deterioration (abnormality) has occurred due to "clogging" or the like that affects the pressure or flow rate of the gas supplied to the measurement target removal section.

The analysis device further includes a notification unit. The notification unit notifies the user that the measurement target removal unit has been determined to be degraded. This allows the user to be notified that the measurement target removal unit has degraded.

The analytical device further includes a housing. The housing houses the filling section, the irradiation section, and the propagation section and isolates them from the outside space. This allows for a structure that isolates the components for analyzing the gas to be measured from the outside space.

The gas separation membrane separates the nitrogen gas from the gas and uses it as purge gas. This makes it possible to generate nitrogen gas as purge gas without increasing the burden on the user.

The gases measured are carbon dioxide (CO ₂ ), carbon monoxide (CO), methane (CH ₄ ), sulfur dioxide (SO ₂ ), ammonia (NH ₃ ), nitrogen oxides (NOx), hydrogen chloride (HCl), water (H ₂ O), ethane (C ₂ H ₆ ), acetylene (C ₂ H ₂ ), propane (C ₃ H ₈ ), ethylene (C ₂ H ₄ ), hexane (n-C ₆ H ₁₄ ), propylene (C ₃ H ₆ ), hydrogen sulfide (H ₂ S), isobutene (i-C ₄ H ₈ ), methanol (CH ₃ OH), phosgene (COCl ₂ ), butane (n-C ₄ H ₁₀ ), chloroethylene (C ₂ H ₃ Cl), methyl nitrite (CH ₃ ONO), cyclohexane (C ₆ H ₁₂ ), butadiene (C ₄ H ₆ ), isobutane (i-C ₄ H ₁₀ ), isopentane (i-C ₅ H ₁₂ ), toluene (C ₆ H ₅ CH ₃ ), hydrogen (H ₂ ), hydrogen fluoride (HF), and trifluoropropene (C ₃ H ₃ F ₃ ). This allows the generation of purge gas without increasing the burden on the user in an analytical device that measures the above.

An analysis system according to another aspect of the present invention includes the above-mentioned analysis device and an alarm device that notifies information output from the analysis device. This makes it possible to realize a system in which the analysis device and the alarm device that notifies information related to the analysis device are separated.

According to yet another aspect of the present invention, an analytical apparatus is an apparatus for analyzing a measurement target gas based on the intensity of measurement light passing through a sample gas containing the measurement target gas and the intensity of measurement light passing through a reference gas used as a standard for analysis of the measurement target gas. The analytical apparatus includes a filling unit, an irradiation unit, and a measurement target removal unit.
The filling section is filled with a gas including a sample gas or a reference gas. The irradiation section irradiates the filling section with a measurement light. The measurement target removal section has a gas separation membrane that separates the measurement target gas from the reference gas generation gas to generate the reference gas.
In the above analytical device, the measurement target removal unit has a gas separation membrane that separates the measurement target gas from the reference gas generation gas to generate the reference gas. Since this gas separation membrane can be used for a long period of time, frequent replacement of the measurement target removal unit is not required. As a result, it is possible to prevent an increase in the burden on the user in analyzing the measurement target gas.

In addition, because the measurement target removal section has a long life, it is no longer necessary to configure the analytical device in a complex manner, such as by switching between multiple gas lines to generate reference gas, and control of the analytical device can be simplified.

The analytical device further includes an introduction section. The introduction section alternately introduces the sample gas and the reference gas into the filling section. This makes it possible to realize a cross-flow modulation type analytical device for measuring the gas to be measured.

The gas used to generate the reference gas is the sample gas. This allows a more appropriate reference gas to be generated from the sample gas to be measured.

The reference gas generation gas is air supplied from a different source than the sample gas. This makes it easy to set the conditions of the reference gas generation gas supplied to the measurement target removal section to appropriate conditions that allow the measurement target removal section to fully demonstrate its performance.

The analytical device further includes a detection unit and a determination unit. The detection unit detects the measurement light that has passed through the filling unit. The determination unit determines deterioration of the measurement target removal unit based on the intensity of the measurement light that has passed through the filling unit filled with the reference gas.
This makes it possible to easily determine the deterioration state of the measurement target removal section by a method similar to that for the measurement target gas based on the intensity of measurement light that has passed through the gas filled in the filling section.

The analysis device further includes a notification unit. The notification unit notifies the user that the measurement target removal unit has been determined to be degraded. This allows the user to be notified that the measurement target removal unit has degraded.

The analytical device further includes a scrubber that removes the measurement target gas from the gas that has passed through the measurement target removal section. This makes it possible to extend the life of the scrubber.

The gases measured are carbon dioxide (CO ₂ ), carbon monoxide (CO), methane (CH ₄ ), sulfur dioxide (SO ₂ ), ammonia (NH ₃ ), nitrogen oxides (NOx), hydrogen chloride (HCl), water (H ₂ O), ethane (C ₂ H ₆ ), acetylene (C ₂ H ₂ ), propane (C ₃ H ₈ ), ethylene (C ₂ H ₄ ), hexane (n-C ₆ H ₁₄ ), propylene (C ₃ H ₆ ), hydrogen sulfide (H ₂ S), isobutene (i-C ₄ H ₈ ), methanol (CH ₃ OH), phosgene (COCl ₂ ), butane (n-C ₄ H ₁₀ ), chloroethylene (C ₂ H ₃ Cl), methyl nitrite (CH ₃ ONO), cyclohexane (C ₆ H ₁₂ ), butadiene (C ₄ H ₆ ), isobutane (i-C ₄ H ₁₀ ), isopentane (i-C ₅ H ₁₂ ), toluene (C ₆ H ₅ CH ₃ ), hydrogen (H ₂ ), hydrogen fluoride (HF), and trifluoropropene (C ₃ H ₃ F ₃ ). This allows the generation of purge gas and zero gas in an analyzer that measures the above gases without increasing the burden on the user.

In an analytical device that analyzes a gas to be measured, gases that do not contain the gas to be measured, such as purge gas and reference gas, can be supplied without increasing the burden on the user.

FIG. 1 is a diagram showing the configuration of an analysis device according to a first embodiment. FIG. 2 is a diagram showing a specific configuration of a control unit according to the first embodiment. 4 is a flowchart showing an analysis operation of the analysis device according to the first embodiment. 4 is a flowchart showing a calibration operation of the analyzer according to the first embodiment. FIG. 13 is a diagram showing a modified example of the analysis device according to the first embodiment. FIG. 13 is a diagram showing the configuration of an analysis device according to a second embodiment. 10 is a flowchart showing an analysis operation of an analysis device according to a second embodiment. FIG. 13 is a diagram showing the configuration of a first modified example of the analysis device according to the second embodiment. FIG. 13 is a diagram showing a specific configuration of a control unit according to a first modified example of the second embodiment. 13 is a flowchart showing the operation of determining deterioration of the measurement target removal unit in the analyzer according to the first modified example of the second embodiment. FIG. 13 is a diagram showing the configuration of a second modified example of the analysis device according to the second embodiment.

1. First embodiment (1) Overall configuration of the analyzer An analyzer 100 according to the first embodiment will be described below with reference to Fig. 1. Fig. 1 is a diagram showing the configuration of the analyzer according to the first embodiment. The analyzer 100 is a device that analyzes a measurement target gas contained in a sample gas SG, such as an exhaust gas generated from a flue.
Examples of measurement target gases that can be measured by the analytical device 100 include carbon dioxide (CO ₂ ), carbon monoxide (CO), sulfur oxides (SOx) (e.g., sulfur dioxide (SO ₂ )), ammonia (NH ₃ ), nitrogen oxides (NOx) (e.g., nitric oxide (NO), nitrogen dioxide (NO ₂ ), nitrous oxide (N ₂ O)), hydrogen chloride (HCl), water (H ₂ O), various hydrocarbons (e.g., methane (CH ₄ ), ethane (C ₂ H ₆ ), acetylene (C ₂ H ₂ ), propane (C ₃ H 8 ), ethylene (C ₂ H ₄ ), hexane (n-C ₆ H ₁₄ ), propylene (C ₃ H ₆ ), isobutene (i-C ₄ H ₈ ), butane (n-C ₄ H ₁₀ ), cyclohexane (C ₆ H 12 ) , butadiene (C ₆ H ₁₄ ), and the like. _4H6 ), isobutane (i- _C4H10 ), isopentane ( _i - _C5H12 ), toluene ( _C6H5CH3 ), etc.), _hydrogen sulfide ( _{H2S), methanol (CH3OH )} , phosgene ( _COCl2 ), chloroethylene ( _C2H3Cl ), methyl _nitrite ( _CH3ONO ), hydrogen ( _H2 ), hydrogen fluoride ( _HF ), _{trifluoropropene} ( _C3H3F3 ), etc. The gas to be measured is not limited to one type _, and may be a mixed gas containing two _or more of _the above gases.

In addition, as described below, the analytical device 100 has a structure that allows the components for analyzing the target gas to be measured to be isolated from the external space, making it possible to accurately measure the target gas even if the environment surrounding the analytical device 100 contains flammable gas.
As shown in FIG. 1, the analysis device 100 includes a housing 1 , a filling unit 3 , an irradiation unit 5 , a propagation unit 7 , a measurement target removal unit 9 , and a control unit 20 .

(2) Housing The housing 1 constitutes the main body of the analysis device 100, and houses the filling unit 3, the irradiation unit 5, and the propagation unit 7 in its internal space IS. An air supply line 11 is also provided in the internal space IS of the housing 1. That is, in this embodiment, the measurement target removal unit 9 generates a purge gas from air supplied from the air supply line 11.
The air supply line 11 is connected to an air supply unit 12, and introduces the air AR supplied from the air supply unit 12 into the internal space IS of the housing 1. The air supply unit 12 is a device that is provided, for example, at the installation location of the analytical device 100, and supplies instrumentation air to be used at the installation location. Specifically, the air supply unit 12 is a system that includes a compressor that compresses the air AR, and various filters that remove dust, oil, and the like contained in the air AR.
Furthermore, the housing 1 is provided with an exhaust port 13. The exhaust port 13 exhausts the air AR supplied from the air supply line 11 to the outside.

A pressure gauge PR1 may be provided at the outlet of the measurement object removal section 9 (purge gas supply line 77 (described later)). The pressure of the purge gas PG (i.e., air AR) measured by the pressure gauge PR1 can be used, for example, to monitor the "clogging" of the measurement object removal section 9. Also, instead of the pressure gauge PR1, a flow meter that measures the flow rate of the purge gas PG (i.e., air AR) may be provided at the outlet of the measurement object removal section 9. Furthermore, both the pressure gauge PR1 and the above-mentioned flow meter may be provided at the outlet of the measurement object removal section 9. At least one of the pressure gauge PR1 and the flow meter may be provided in the propagation space TS. Also, at least one of the pressure gauge PR1 and the flow meter may be provided in the air supply line 11 between the air supply section 12 and the measurement object removal section 9.

Because the housing 1 has the above-mentioned configuration, in the analysis device 100 according to the first embodiment, air AR is supplied from the air supply line 11 to the internal space IS of the housing 1, while the air AR in the internal space IS is exhausted from the exhaust port 13, thereby purging the internal space IS with air AR. As a result, the internal space IS is made into an air atmosphere that does not contain dangerous gases such as flammable gases, and a structure can be formed in which these gases do not enter the internal space IS.

(3) Filling section The filling section 3 is made of a transparent material such as quartz, calcium fluoride, or barium fluoride that hardly absorbs the measurement light L (described later), and the sample gas SG can be filled inside. The space in the filling section 3 where the sample gas SG is filled is called the "sampling space SS." In order to fill the sampling space SS with the sample gas SG, the filling section 3 is provided with an inlet 31 for introducing the sample gas SG into the sampling space SS, and an outlet 32 for discharging the sample gas SG from the sampling space SS. During analysis of the measurement target gas contained in the sample gas SG, the sample gas SG continues to fill the sampling space SS from the inlet 31 and then be discharged from the outlet 32.

In addition, a first reflecting member 33a and a second reflecting member 33b are provided in the sampling space SS. The first reflecting member 33a and the second reflecting member 33b cause multiple reflection of the measurement light L incident on the sampling space SS, and then propagate the measurement light L toward the propagation space TS (described later) of the propagation section 7. This makes it possible to increase the optical path length of the measurement light L passing through the sample gas SG filled in the sampling space SS.

The first reflecting member 33a is provided at a position close to the propagation section 7 in the sampling space SS. The first reflecting member 33a reflects the measurement light L and propagates the measurement light L toward the second reflecting member 33b. The first reflecting member 33a also propagates the multiple-reflected measurement light L toward the propagation section 7. Therefore, the first reflecting member 33a is a member that can reflect light, such as a half mirror, and can transmit a portion of the light.

The second reflecting member 33b is provided at a position away from the propagation section 7 in the sampling space SS. The second reflecting member 33b reflects the measurement light L toward the first reflecting member 33a. Unlike the first reflecting member 33a, the second reflecting member 33b does not need to be able to transmit light, so for example, a mirror can be used as the second reflecting member 33b.

(4) Irradiation Unit The irradiation unit 5 generates measurement light L. The measurement light L generated from the irradiation unit 5 is guided to the filling unit 3 by the propagation unit 7. The irradiation unit 5 according to this embodiment is composed of multiple light sources 51a to 51d. The multiple light sources 51a to 51d output multiple element light beams L1 to L4 having different wavelength regions, respectively. The multiple light sources 51a to 51d are, for example, laser oscillators such as semiconductor laser devices.

As described below, the element light beams L1 to L4 generated from the multiple light sources 51a to 51d are multiplexed in the propagation space TS of the propagation section 7 and propagate toward the filling section 3 as the measurement light beam L. That is, the measurement light beam L is composed of multiple element light beams L1 to L4 having different wavelength regions. By having the measurement light beam L composed of multiple element light beams L1 to L4, it is possible to measure, for example, multiple types of measurement target gases that have absorption peaks in the wavelength regions of each of the element light beams L1 to L4.

By configuring the measurement light L from multiple element lights L1 to L4, it is also possible to measure, for example, the influence of interference gas components on one measurement target gas. An interference gas component is a component that has an absorption peak at the same or similar position as part of the absorption peak of the measurement target gas, and as a result, affects the analysis result of the measurement target gas. If the influence of the interference gas component can be measured, the influence of the interference gas component can be removed from the measurement result of the measurement light L received by the detection unit 75 (described later), and the measurement target gas can be analyzed with high accuracy. Note that the meaning of "removal" includes not only eliminating the influence of the interference gas component at all, but also reducing the degree of influence compared to before removal.

(5) Propagation Section The propagation section 7 is provided between the filling section 3 and the irradiation section 5. Specifically, as shown in Fig. 1, the propagation section 7 has an L-shape, and a plurality of light sources 51a to 51d are fixed in a state in which they are partially inserted into a portion corresponding to one side of the L-shape. Meanwhile, the filling section 3 is fixed to an end of the other side of the L-shape of the propagation section 7 via an optical window W. The filling section 3 and the propagation section 7 can be fixed together, for example, by using a flange F.

In addition, multiple mirrors are arranged in the internal space of the propagation section 7. The element light L1 to L4 output from the irradiation section 5 has its propagation path changed by these mirrors and propagates to the filling section 3. In other words, the measurement light L propagates through the internal space of the propagation section 7 while being reflected by at least one mirror. Hereinafter, the internal space of the propagation section 7 through which the measurement light L propagates is referred to as the "propagation space TS."

Specifically, a first mirror 71 a, a second mirror 71 b, a third mirror 71 c, a fourth mirror 71 d, and a fifth mirror 71 e are arranged in the propagation space TS, and a first optical element 73 a, a second optical element 73 b, and a third optical element 73 c are arranged in the propagation space TS.
The first mirror 71a reflects the element light L1 toward the first optical element 73a. The first optical element 73a reflects the element light L1 and transmits the element light L2. That is, the first optical element 73a multiplexes the element light L1 and the element light L2. The element light L1 and the element light L2 multiplexed by the first optical element 73a travel along the same optical path toward the second mirror 71b.

The second mirror 71b reflects the element light L1 and element light L2 multiplexed by the first optical element 73a toward the second optical element 73b. The second optical element 73b reflects the multiplexed element light L1 and element light L2, and transmits element light L3. In other words, the second optical element 73b multiplexes the element light L1, element light L2, and element light L3. The element light L1 to L3 multiplexed by the second optical element 73b travel along the same optical path toward the third mirror 71c.

The third mirror 71c reflects the element light L1 to L3 multiplexed by the second optical element 73b toward the third optical element 73c. The third optical element 73c reflects the multiplexed element light L1 to L3 and transmits element light L4. That is, the third optical element 73c multiplexes element light L1, element light L2, element light L3, and element light L4. The element light L1 to L4 multiplexed by the third optical element 73c travels along the same optical path toward the fourth mirror 71d.

The fourth mirror 71d reflects the element light L1 to L4 multiplexed by the third optical element 73c toward the fifth mirror 71e. The element light L1 to L4 multiplexed in the manner described above becomes the measurement light L.

The fifth mirror 71e changes the propagation path of the measurement light L, which is the multiplexed light components L1 to L4, to the direction of arrangement of the filling section 3. The measurement light L, whose propagation path has been changed by the fifth mirror 71e, passes through the optical window W and propagates into the sampling space SS of the filling section 3. These mirrors are provided within the propagation space TS, which prevents the inflow of unnecessary gas from the outside and keeps the mirrors in a clean state.

A detection unit 75 is disposed in the propagation space TS of the propagation unit 7. The detection unit 75 detects the measurement light L that is incident on the sampling space SS and is multiple-reflected. For example, a thermal type photodetection element such as a thermopile, a semiconductor detection element, or a quantum type photoelectric element can be used as the detection unit 75. Furthermore, by purging the propagation space TS with a purge gas PG, the purge gas flows in the propagation space TS, and the state of the detection unit 75 provided in the propagation space can be made clean.
As shown in FIG. 1, a sixth mirror 71f is provided in the propagation space TS to change the propagation path of the measurement light L that has been multiple-reflected in the sampling space SS and returned to the propagation section 7, toward the direction in which the detection section 75 is disposed.

The propagation part 7 also has a purge gas supply line 77 and a purge gas exhaust port 79. The purge gas supply line 77 is connected to the measurement target removal part 9 and introduces the purge gas PG generated by the measurement target removal part 9 into the propagation space TS. The purge gas exhaust port 79 exhausts the purge gas PG introduced into the propagation space TS into the internal space IS of the housing 1.
By providing a purge gas supply line 77 and a purge gas exhaust port 79 in the propagation section 7, in the analytical apparatus 100 of the first embodiment, purge gas PG can be introduced from the purge gas supply line 77 into the propagation space TS of the propagation section 7 while the purge gas PG in the propagation space TS is exhausted from the purge gas exhaust port 79, thereby purging the propagation space TS with the purge gas PG.

As described below, the purge gas PG is a gas in which the measurement target gas has been removed from the air AR, so purging the propagation space TS with the purge gas PG can prevent the measurement light L from being absorbed by the measurement target gas while propagating from the irradiation section 5 to the filling section 3. In addition, purging the propagation space TS with the purge gas PG allows the purge gas PG to flow within the propagation space TS, and the state of the multiple mirrors provided within the propagation space TS can be kept clean.

(6) Measurement Target Removal Unit The measurement target removal unit 9 is provided on the purge gas supply line 77, and removes the measurement target gas from the air AR supplied from the air supply unit 12, to generate a purge gas PG.
The measurement target removal unit 9 is, for example, a member called an "N ₂ separator" in which a hollow member is filled with a polyimide hollow fiber membrane or a gas separation membrane. The N ₂ separator separates the introduced air into a nitrogen-rich gas (i.e., a gas containing almost no components other than nitrogen gas) and an oxygen-rich gas (i.e., the remaining gas after removing nitrogen from the air AR) by introducing compressed air into the hollow fiber membrane or the gas separation membrane. The measurement target removal unit 9, which is an N ₂ separator, discharges the nitrogen-rich gas to the purge gas supply line 77 as a purge gas PG, while discharging the oxygen-rich gas to the outside (the internal space IS of the housing 1).

The hollow fiber membrane may be composed of, for example, polyimide, polyamide, polysulfone, cellulose acetate and its derivatives, polyphenylene oxide, polysiloxane, a polymer that is itself microporous, a mixed matrix membrane, a facilitated transport membrane, polyethylene oxide, polypropylene oxide, a carbon membrane, a zeolite, or a mixture thereof.

The nitrogen-rich gas separated by the hollow fiber membrane and gas separation membrane of the _N2 separator contains almost no target gas. In other words, the _N2 separator separates the target gas from the air and generates a nitrogen-rich gas that does not contain the target gas as the purge gas PG.
Furthermore, since the N ₂ separator can also separate moisture, it can also be applied to devices that analyze measurement target gases whose analysis results are affected by moisture.

In the _N2 separator, as long as the compressed air introduced is not contaminated, the function of separating nitrogen-rich gas and oxygen-rich gas from the air does not deteriorate for a long time. Therefore, by using an _N2 separator as the measurement target removal unit 9, replacement of the measurement target removal unit 9 is almost unnecessary.

1, in this embodiment, the measurement target removal unit 9 is disposed in the internal space IS of the housing 1. As a result, for example, instead of introducing air AR supplied from the air supply unit 12 to purge the internal space IS with the air AR, it is also possible to introduce an _oxygen -rich gas discharged from the measurement target removal unit 9, which is an N2 separator, and a nitrogen-rich gas discharged from a purge gas outlet 79 into the internal space IS, thereby substantially purging the internal space IS with the air AR.

However, this is not limited to the above, and for example, in cases where discharging oxygen-rich gas outside the housing 1 does not pose a safety issue, or where the main body of the measurement target removal unit 9 (hollow fiber membrane, gas separation membrane, hollow member filled with pharmaceuticals, etc.) will not be damaged even if it is placed outside the housing 1, the measurement target removal unit 9 may be placed outside the housing 1.

(7) Control Unit The control unit 20 is a computer system including a CPU, a storage device (e.g., a storage device such as a RAM or a ROM), and various interfaces. The control unit 20 may be a system including each of the above devices individually, or may be a SoC (System on Chip) in which the above devices are integrated on a single chip. The control unit 20 controls the components of the analysis device 100. In addition, the control unit 20 calibrates the analysis device 100 and analyzes the gas to be measured based on the intensity of the measurement light L detected by the detection unit 75.
Hereinafter, a specific configuration of the control unit 20 will be described with reference to Fig. 2. Fig. 2 is a diagram showing a specific configuration of the control unit according to the first embodiment. The control unit 20 mainly includes an analysis unit 201, a first determination unit 203, and a notification unit 205. Note that some or all of the functions of the above-mentioned units of the control unit 20 are realized by executing a program stored in a storage device of a computer system constituting the control unit 20. Also, some of the functions of the above-mentioned units may be realized by hardware.

The analysis unit 201 performs an analysis of the measurement target gas contained in the sample gas SG filled in the filling unit 3. Specifically, the analysis unit 201 controls the irradiation unit 5 (light sources 51a to 51d) to irradiate the measurement light L toward the sampling space SS in the filling unit 3, and receives a signal output by the detection unit 75 upon detecting the measurement light L.
The analysis unit 201 analyzes the target gas based on the intensity in each wavelength region of the measurement light L after passing through a sampling space SS filled with a reference gas (referred to as a reference gas) that does not contain the target gas, and the intensity in each wavelength region of the measurement light L after passing through a sampling space SS filled with a sample gas SG. For example, the analysis unit 201 calculates the concentration of the target gas contained in the sample gas SG.

The intensity of the measurement light L after passing through the sampling space SS filled with the reference gas is acquired as the intensity of the measurement light L (called the reference intensity) that serves as the basis for analysis when the analysis device 100 is calibrated, and is stored in the storage device. Alternatively, the reference intensity may be acquired when the analysis device 100 is shipped or installed, and stored in the storage device. The reference gas is, for example, nitrogen gas supplied from a cylinder or the like.

The first determination unit 203 determines deterioration of the measurement target removal unit 9 based on the intensity of the measurement light L absorbed by a gas that affects the measurement target gas and the measurement light L by passing through the propagation space TS. Specifically, the first determination unit 203 determines whether the measurement target removal unit 9 has deteriorated based on a comparison between a reference intensity obtained during a calibration operation in which the measurement light L is detected by the detection unit 75 while filling the filling unit 3 with a reference gas, and a reference intensity obtained when the analysis device 100 is shipped, installed, etc., or when the measurement target removal unit 9 is replaced.

If the measurement target removal unit 9 is not deteriorated, the purge gas PG contains almost no measurement target gas. Therefore, the intensity of the measurement light L obtained by filling the sampling space SS' of the filling unit 3 with the reference gas is approximately the same at present as it was in the past.
On the other hand, when the measurement target removal unit 9 is deteriorated, the ability to remove the measurement target gas from the air AR decreases, so that the measurement target gas is contained in the purge gas PG. As a result, the measurement light L is absorbed by the measurement target gas contained in the purge gas PG while propagating through the propagation space TS, and the intensity of the measurement light L obtained by filling the sampling space SS' of the filling unit 3 with the reference gas differs between the present and the past. Specifically, the present intensity becomes smaller than the past intensity.

Using the above principle, the first judgment unit 203 can judge that the measurement target removal unit 9 has deteriorated if the intensity of the measurement light L obtained when the reference gas is filled into the sampling space SS of the filling unit 3 decreases by a predetermined intensity or more compared to the intensity of the measurement light L obtained in the past when the reference gas was filled into the sampling space SS of the filling unit 3.

If the first judgment unit 203 judges that the measurement target removal unit 9 is degraded, it notifies the notification unit 205 of the judgment result.

When the notification unit 205 receives a judgment result from the first judgment unit 203 that the measurement target removal unit 9 is degraded, the notification unit 205 notifies that the measurement target removal unit 9 is degraded. Specifically, when the notification unit 205 judges that the measurement target removal unit 9 is degraded, it outputs a signal to operate the alarm device 30. The alarm device 30 is, for example, a device that emits sound (speaker), a warning light, a device that displays an image on a screen (display), etc. In this way, the alarm device 30 is a device that notifies information output from the analysis device 100.

The alarm device 30 can be a separate device from the analysis device 100 to form an analysis system. By making the alarm device 30 and the analysis device 100 separate devices, for example, the alarm device 30 can be installed in a location different from the location where the analysis device 100 is installed.

When the pressure gauge PR1 is provided, the control unit 20 may have a second determination unit 207. The second determination unit 207 monitors the pressure measured by the pressure gauge PR1, and determines that the measurement target removal unit 9 has deteriorated due to clogging or the like when the measured pressure increases by a predetermined value or more from the normal pressure (for example, the pressure when the measurement target removal unit 9 is operating normally without clogging or the like). This makes it possible to detect deterioration of the measurement target removal unit 9 at least without measuring the intensity of the measurement light L that has passed through the propagation space TS.
If the second determination section 207 determines that the measurement target removal section 9 has deteriorated, it notifies the notification section 205 of the determination result.

(8) Operation of the Analysis Device According to the First Embodiment (8-1) Analysis Operation The operation of the analysis device 100 according to the first embodiment will be described below. First, the analysis operation in the analysis device 100 will be described with reference to FIG. 3. FIG. 3 is a flow chart showing the analysis operation of the analysis device according to the first embodiment. Note that the operation described below is executed by the control unit 20 controlling the analysis device 100.
Prior to analysis of the measurement target gas contained in the sample gas SG, in step S1, the internal space IS of the housing 1 is purged with air AR. Specifically, while supplying air AR from the air supply unit 12 to the air supply line 11, the gas (air AR) in the internal space IS is discharged from the exhaust port 13 for a predetermined period of time.

While the internal space IS is purged with the air AR, in step S2, the propagation space TS of the propagation unit 7 is purged with a purge gas PG. Specifically, in step S1, air AR is continuously supplied from the air supply unit 12 to the air supply line 11 for a predetermined time, whereby the air AR is supplied to the measurement target removal unit 9, and the measurement target removal unit 9 removes the measurement target gas from the supplied air AR to generate a purge gas PG, which is discharged to the purge gas supply line 77.
By continuously supplying air AR to the air supply line 11 for a predetermined period of time, purge gas PG is supplied from the purge gas supply line 77 to the propagation space TS while the gas (purge gas PG) in the propagation space TS is discharged from the purge gas exhaust port 79 for a predetermined period of time, thereby purging the propagation space TS with the purge gas PG.

The specified time for supplying air AR to the air supply line 11 can be, for example, the longer of either the time during which the internal space IS of the housing 1 can be replaced with air AR supplied by the air supply line 11, or the time during which the propagation space TS of the propagation section 7 can be replaced with purge gas PG.
The time during which the internal space IS can be replaced by the air AR can be determined based on, for example, the volume of the internal space IS and the flow rate of the air AR. Also, the time during which the propagation space TS can be replaced by the purge gas PG can be determined based on, for example, the volume of the propagation space TS and the flow rate of the purge gas PG.

By providing the measurement target removal unit 9 in the air supply line 11 of the analytical device 100, as described above, the purge gas PG can be generated using the air AR supplied from the air supply line 11. As a result, it is no longer necessary to prepare a gas cylinder for purging the propagation space TS and install it in the analytical device 100, thereby reducing the burden on the user.

After purging the internal space IS and the propagation space TS, in step S3, it is determined whether calibration of the analytical device 100 is necessary. For example, it can be determined that calibration of the analytical device 100 is necessary if a predetermined period of time (e.g., one week) has passed since the last calibration, or if analysis of the gas to be measured has been performed a predetermined number of times since the last calibration.

If it is determined that calibration of the analytical device 100 is to be performed ("Yes" in step S3), calibration of the analytical device 100 is performed in step S4. The specific calibration operation in step S4 will be described in detail later.
On the other hand, if it is determined that calibration of the analytical device 100 is not to be performed ("No" in step S3), the analytical operation proceeds to step S5, where analysis of the measurement target gas is performed.

After calibration of the analytical device 100 has been performed, or after it has been determined that calibration is not necessary, the analytical unit 201 starts analysis of the measurement target gas in step S5. Specifically, the analysis is performed as follows.
First, the sample gas SG is supplied to the sampling space SS of the filling unit 3 to fill the sampling space SS with the sample gas SG. While supplying the sample gas SG to the sampling space SS, the analysis unit 201 controls the light sources 51a to 51d of the irradiation unit 5 to output the measurement light L toward the sampling space SS of the filling unit 3. The analysis unit 201 receives a detection signal of the measurement light L that has passed through the sampling space SS from the detection unit 75, and calculates the intensity in the wavelength region of each of the element lights L1 to L4 of the detected measurement light L based on the detection signal.

Then, the analysis unit 201 calculates the concentration of the gas to be measured contained in the sample gas SG based on, for example, the ratio between the intensity (i.e., reference intensity) in the above-mentioned wavelength region of the measurement light L before passing through the sampling space SS filled with the sample gas SG and the intensity in the above-mentioned wavelength region of the measurement light L after passing through the sampling space SS filled with the sample gas SG.
For example, when the gas to be measured can absorb all of the element lights L1 to L4, the analysis unit 201 calculates the concentration of an interference gas that interferes with the analysis result of the gas to be measured based on the intensity in the wavelength region of each of the element lights L1 to L4, and can accurately calculate the concentration of the gas to be measured taking into account the influence of this interference gas.

In addition, when there are multiple gases to be measured, the analysis unit 201 can calculate the concentration of the gas to be measured, for example, based on the intensity of one of the wavelength regions of the element lights L1 to L4 that can be absorbed by the gas to be measured.

If it is desired to continue the analysis of the measurement target gas after one analysis is completed, the above step S5 is repeated. On the other hand, if it is desired to end the analysis of the measurement target gas, the generation of the measurement light L from the irradiation unit 5 is stopped, and the above analysis operation is ended.

(8-2) Calibration Operation of the Analytical Device Next, the calibration operation of the analytical device 100 according to the first embodiment executed in step S4 above will be described with reference to Fig. 4. Fig. 4 is a flow chart showing the calibration operation of the analytical device according to the first embodiment. Note that the operation described below is executed by the control unit 20 controlling the analytical device 100.
In the analytical device 100 according to the first embodiment, the intensity (i.e., reference intensity) of the measurement light L that has passed through a reference gas that does not contain a measurement target gas is acquired during calibration of the analytical device 100, and then deterioration of the measurement target removal unit 9 is determined. Specifically, the following steps S41 to S45 are executed as the calibration operation.

First, in step S41, a reference gas (gas not including a gas to be measured) is filled into the sampling space SS of the filling unit 3. In this embodiment, the reference gas is nitrogen gas.
After the sampling space SS is filled with the reference gas, in step S42, the intensity of the measurement light L that has passed through the sampling space SS filled with the reference gas is measured. Specifically, the control unit 20 controls the light sources 51a to 51d of the irradiation unit 5 to output the measurement light L toward the sampling space SS filled with the reference gas. The control unit 20 receives a detection signal of the measurement light L that has passed through the sampling space SS from the detection unit 75, and calculates the intensity of the detected measurement light L based on the detection signal.

Then, in step S43, the control unit 20 determines the intensity of the measurement light L calculated in step S42 as the intensity of the measurement light L before passing through the sampling space SS filled with the sample gas SG (i.e., the reference intensity) and stores it in the memory device of the control unit 20. By acquiring and storing the reference intensity, the calibration of the analysis device 100 can be performed.

After the reference intensity is acquired and stored to calibrate the analytical device 100, in step S44, it is determined whether or not the measurement target removal unit 9 has deteriorated.
Specifically, the first judgment unit 203 compares the reference intensity obtained by the current calibration with a reference intensity obtained in the past (for example, when the analysis device 100 was shipped or installed, or when the measurement target removal unit 9 was last replaced), and if the reference intensity obtained this time is smaller than the reference intensity obtained in the past by a predetermined value or more, it judges that the measurement target removal unit 9 has deteriorated.

As described above, the reference intensity is measured when the sampling space SS is filled with the reference gas, i.e., when the measurement light L is not absorbed while passing through the sampling space SS. Therefore, the reference intensity acquired this time being smaller than the reference intensity acquired in the past means that the amount of light absorbed while the measurement light L is passing through the propagation space TS during the current calibration is greater than the amount of light absorbed while the measurement light L was passing through the propagation space TS in the past.

Furthermore, the fact that the amount of light absorbed while the measurement light L is passing through the propagation space TS during the current calibration is greater than the amount of light absorbed while the measurement light L was passing through the propagation space TS in the past means that the amount (concentration) of the measurement target gas contained in the purge gas PG during the current calibration is greater than the amount (concentration) of the measurement target gas contained in the purge gas PG in the past, and means that the ability of the measurement target removal unit 9 to remove the measurement target gas has decreased.

In this way, in step S44, the first determination unit 203 can determine the deterioration of the measurement target removal unit 9 based on the intensity of the measurement light L that has passed through the propagation space TS by comparing the current and past reference intensities. That is, in the analysis device 100 according to the first embodiment, the deterioration state of the measurement target removal unit 9 can be easily determined by a method similar to the analysis of the measurement target gas.

In addition, if a pressure gauge PR1 is provided, the second judgment unit 207 compares the pressure measured by the pressure gauge PR1 during the current calibration with the pressure measured by the pressure gauge PR1 in the past (for example, when the analytical device 100 was shipped or installed, or when the measurement target removal unit 9 was last replaced), and if the pressure measured this time is greater than the pressure measured in the past by a predetermined value or more, it judges that the measurement target removal unit 9 has deteriorated.

The fact that the pressure measured this time is greater than the pressure measured previously means that the measurement target removal unit 9 has deteriorated as a result of poor gas flow within the measurement target removal unit 9 due to clogging or the like occurring in the measurement target removal unit 9 before the current calibration. On the other hand, if a flow meter is provided instead of the pressure gauge PR1, the fact that the flow rate measured this time is smaller than the flow rate measured previously means that the measurement target removal unit 9 has deteriorated.
In this way, the second determination unit 207 determines whether or not the gas flow in the measurement target removal unit 9 has deteriorated based on the pressure or flow rate of the air supplied to the measurement target removal unit 9, and can determine that the measurement target removal unit 9 has deteriorated if the gas flow has deteriorated. In other words, the second determination unit 207 can determine whether or not deterioration (abnormality) has occurred due to "clogging" or the like that affects the pressure and flow rate of the air AR supplied to the measurement target removal unit 9.

If the first judgment unit 203 and/or the second judgment unit 207 judges that the measurement target removal unit 9 is degraded ("Yes" in step S44), in step S45, the first judgment unit 203 and/or the second judgment unit 207 notifies the notification unit 205 of the judgment result that the measurement target removal unit 9 is degraded.
The notification unit 205, which has received the determination result that the measurement target removal unit 9 has deteriorated, outputs a notification signal to the alarm device 30 to operate the alarm device 30. This allows the user to be notified that the measurement target removal unit 9 has deteriorated in a form that can be visually and/or audibly recognized by, for example, emitting a sound and/or turning on a warning light.

A user who recognizes that measurement target removal unit 9 has deteriorated can take measures such as replacing measurement target removal unit 9 .
In addition, if it is thought that deterioration of the measurement target removal unit 9 is caused by the air supply unit 12 not sufficiently removing substances that cause deterioration of the measurement target removal unit 9 (e.g., oil mist, dust, etc.), the user can also replace a filter provided in the air supply unit 12 that removes causative substances such as oil mist and dust.

On the other hand, if the first judgment unit 203 and/or the second judgment unit 207 do not judge that the measurement target removal unit 9 is degraded ('No' in step S44), the calibration operation of the analysis device 100 is terminated.

(9) Modification of the analytical device according to the first embodiment In the first embodiment described above, the supply line for air AR that purges the internal space IS of the housing 1 and the supply line for air AR that is supplied to the measurement target removal section 9 were shared as the air supply line 11.
However, without being limited thereto, as shown in Fig. 5, in a modified example (analytical device 100') of the analytical device according to the first embodiment, the supply line for air AR for purging the internal space IS of the housing 1 may be a first air supply line 11a, and the supply line for air AR for supplying to the measurement target removal unit 9 may be a second air supply line 11b, and the air supply lines may be provided separately. Fig. 5 is a diagram showing a modified example of the analytical device according to the first embodiment.

Furthermore, in the analytical device 100', a three-way valve 11c is provided at the junction of the purge gas supply line 77, the first air supply line 11a, and the line from the measurement target removal unit 9. When it is desired to purge the internal space IS of the housing 1 with air AR, the three-way valve 11c allows gas to flow between the first air supply line 11a and the purge gas supply line 77. This allows the internal space IS and the propagation space TS of the housing 1 to be purged with air AR.
On the other hand, when it is desired to purge the propagation space TS of the propagation part 7 with the purge gas PG, the three-way valve 11c allows gas to flow between the line from the measurement target removal part 9 and the purge gas supply line 77. This allows the propagation space TS to be purged with the purge gas PG.

In this way, by providing a separate supply line for air AR, air AR can be supplied to the measurement target removal section 9 only when necessary to generate purge gas PG, thereby reducing the frequency of replacement of the measurement target removal section 9.

(10) Summary of First Embodiment The first embodiment described above can be summarized as follows.
In the analysis device 100, 100' according to the first embodiment, a purge gas PG for purging the propagation space TS through which the measurement light L propagates by being reflected by at least one mirror before reaching the filling section 3 is generated by the measurement target removal section 9 having a gas separation membrane. This eliminates the need for work that increases the burden on the user, such as frequent replacement of cylinders for supplying purge gas. In other words, it is possible to generate and supply the purge gas PG without increasing the burden on the user.

The analytical device 100, 100' is equipped with a first determination unit 203 that determines the deterioration of the measurement target removal unit 9 based on the intensity of the measurement light L that has passed through the propagation space TS. This makes it possible to easily determine the deterioration state of the measurement target removal unit 9 by a method similar to the analysis of the measurement target gas.

The analysis device 100, 100' may include a second determination unit 207 that determines deterioration of the measurement target removal unit 9 based on the pressure or flow rate of the air AR supplied to the measurement target removal unit 9. This makes it possible to determine whether deterioration (abnormality) has occurred due to "clogging" or the like that affects the pressure or flow rate of the air AR supplied to the measurement target removal unit 9.

The analysis device 100, 100' further includes a notification unit 205 that notifies the user that the measurement target removal unit 9 has been determined to be degraded. This allows the user to be notified that the measurement target removal unit 9 has degraded.

The analytical device 100, 100' further includes a housing 1 that houses the filling section 3, the irradiation section 5, and the propagation section 7 and isolates them from the outside space. This allows for a structure that isolates the components for analyzing the gas to be measured from the outside space.

In the first embodiment, the measurement target removal unit 9 has a gas separation membrane that separates nitrogen gas from air, and the nitrogen gas separated by the gas separation membrane is used as the purge gas PG. The ability of the gas separation membrane to separate nitrogen gas and oxygen gas from air lasts for a long period of time, making it almost unnecessary to replace the measurement target removal unit 9. As a result, the burden on the user can be reduced.

2. Second embodiment (1) Overview of the analyzer according to the second embodiment The measurement target removal unit, which is the _N2 separator described in the first embodiment, can be applied to other analyzers that analyze measurement target gases. For example, the measurement target removal unit can be used in the analyzer 200 according to the second embodiment described below.
The analytical device 200 according to the second embodiment will be described in detail below. The analytical device 200 according to the second embodiment is an analytical device of a cross-flow modulation type. The cross-flow modulation type is a method in which a reference gas RG not containing a measurement target gas and a sample gas SG containing a measurement target gas are alternately introduced into the filling section 301, and the measurement target gas contained in the sample gas SG is analyzed based on the intensity of the measurement light L' passing through the filling section 301 filled with the reference gas RG and the intensity of the measurement light L' passing through the filling section 301 filled with the sample gas SG. In the second embodiment, the measurement target removal section 302, which is the N ₂ separator described in the first embodiment, is used to generate the reference gas RG.
In the second embodiment, the sample gas SG is, for example, the air, and the measurement target gas is, for example, carbon dioxide (CO ₂ ) contained in the sample gas SG. Other target gases for measurement include carbon monoxide (CO), sulfur oxides (SOx) (e.g., sulfur dioxide (SO ₂ )), ammonia (NH ₃ ), nitrogen oxides (NOx) (e.g., nitric oxide (NO), nitrogen dioxide (NO ₂ ), nitrous oxide (N ₂ O)), hydrogen chloride (HCl), water (H ₂ O), various hydrocarbons (e.g., methane (CH ₄ ), ethane (C ₂ H ₆ ), acetylene (C 2 H 2 ), propane (C ₃ H ₈ ), ethylene (C ₂ H ₄ ), hexane (n-C ₆ H ₁₄ ), propylene (C ₃ H ₆ ), isobutene (i-C ₄ H ₈ ), butane (n-C ₄ H ₁₀ ), cyclohexane (C ₆ H ₁₂ ), butadiene (C ₄ H ₆ ), isobutane (i-C ₄ H ₈ ), and tetrahydrofuran (TFA _). H ₁₀ ), isopentane (i-C ₅ H ₁₂ ), toluene (C ₆ H ₅ CH ₃ ), etc.), hydrogen sulfide (H ₂ S), methanol (CH ₃ OH), phosgene (COCl ₂ ), chloroethylene (C ₂ H ₃ Cl), methyl nitrite (CH ₃ ONO), hydrogen (H ₂ ), hydrogen fluoride (HF), trifluoropropene (C ₃ H ₃ F ₃ ), etc. The measurement target gas is not limited to one type, and may be a mixed gas containing two or more of the above gases.

The above-mentioned reference gas RG is a gas used as a standard for the analysis of the measurement target gas, and is a gas that does not contain the measurement target gas at all or contains only a small amount of the measurement target gas that does not affect the analysis. Therefore, the intensity of the measurement light L' that passes through the filling section 301 filled with the reference gas RG is the intensity of the measurement light L' as a background contained in the intensity of the measurement light L' that passes through the filling section 301 filled with the sample gas SG.

(2) Specific Configuration of the Analytical Device According to the Second Embodiment Next, a specific configuration of the analytical device 200 according to the second embodiment will be described with reference to Fig. 6. Fig. 6 is a diagram showing the configuration of the analytical device according to the second embodiment. The analytical device 200 mainly includes a filling section 301, a measurement target removal section 302, and an introduction section 303.
The filling section 301 has a sampling space SS' that can be filled with a gas, one end of the sampling space SS' is connected to the gas outlet 303c of the introduction section 303, and the other end is connected to the exhaust flow path 304. By connecting one end of the sampling space SS' to the gas outlet 303c of the introduction section 303, the sampling space SS' can be filled with a sample gas SG or a reference gas RG.

On the other hand, an orifice 304a and a first pump 304b are provided in the discharge flow path 304 to which the other end of the sampling space SS' of the filling section 301 is connected. The flow rate of the sample gas SG or the reference gas RG introduced into the sampling space SS' is determined by the dimensions of the orifice 304a and the flow rate of the first pump 304b.

The filling unit 301 also has an irradiation unit 301a that irradiates the sampling space SS' with measurement light L', and a detection unit 301b that detects the measurement light L' that has passed through the sampling space SS'. The irradiation unit 301a is, for example, a light generating device such as a laser that generates measurement light L' having a wavelength (for example, infrared light) that can be absorbed by the gas to be measured. The detection unit 301b is, for example, a light detection element that can detect the measurement light L'.

The measurement target removal unit 302 generates a reference gas RG to be filled into the sampling space SS' of the filling unit 301 from the reference gas generation gas. Specifically, the measurement target removal unit 302 receives a supply of sample gas SG from a branch line 305 branched off from the exhaust flow path 304, and removes the measurement target gas from the supplied sample gas SG. That is, in the analysis device 200 shown in FIG. 6, the reference gas generation gas is the sample gas SG. This allows a more appropriate reference gas RG to be generated from the sample gas SG to be measured.

In this embodiment, the measurement target removal unit 302 is a member called an " _N2 separator" in which a hollow fiber membrane or a gas separation membrane is filled in a hollow member. The hollow fiber membrane is made of, for example, polyimide, polyamide, polysulfone, cellulose acetate and its derivatives, polyphenylene oxide, polysiloxane, a microporous polymer, a mixed matrix membrane, a facilitated transport membrane, polyethylene oxide, polypropylene oxide, a carbon membrane, a zeolite, or a mixture thereof.

The _N2 separator introduces the compressed sample gas SG into a hollow fiber membrane and a gas separation membrane, and separates the introduced sample gas SG into a nitrogen-rich gas (i.e., a gas containing almost no components other than nitrogen gas) and an oxygen-rich gas (i.e., the remaining gas after removing nitrogen gas from the sample gas SG). The measurement target removal unit 302, which is an _N2 separator, supplies the nitrogen-rich gas to the reference gas supply line 306 as a reference gas RG.

The nitrogen-rich gas separated by the hollow fiber membrane and gas separation membrane of the measurement target removal unit 302, which is an _N2 separator, contains almost no measurement target gas. That is, the measurement target removal unit 302, which is an _N2 separator, separates the measurement target gas from the sample gas SG and can generate a nitrogen-rich gas that does not contain the measurement target gas as the reference gas RG.

As described above, it is necessary to introduce compressed sample gas SG to the measurement target removal unit 302, which is an _N2 separator. Therefore, a pressure boosting pump 305a that boosts the pressure of the sample gas SG and supplies it to the measurement target removal unit 302 is provided in the branch line 305 that supplies the sample gas SG to the measurement target removal unit 302.
Furthermore, a regulator 305b is provided between the boost pump 305a and the measurement target removal unit 302. The regulator 305b keeps constant the pressure of the sample gas SG supplied from the boost pump 305a to the measurement target removal unit 302. This makes it possible to extend the life of the measurement target removal unit 302.

The introduction section 303 introduces the sample gas SG or the reference gas RG into the sampling space SS' of the filling section 301. Specifically, the introduction section 303 has a first inlet 303a, a second inlet 303b, and a gas outlet 303c, and is a three-way valve that can switch between allowing gas to flow between the first inlet 303a and the gas outlet 303c, or allowing gas to flow between the second inlet 303b and the gas outlet 303c.

6, a sample gas SG is supplied to a first inlet 303a of the introduction part 303. Meanwhile, a second inlet 303b is connected to a reference gas supply line 306. That is, a reference gas RG generated in the measurement target removal part 302 is supplied to the second inlet 303b.

During the analysis of the gas to be measured, the introduction section 303 alternately switches between allowing gas to flow through the first inlet 303a and the gas outlet 303c (i.e., discharging the sample gas SG from the gas outlet 303c) and allowing gas to flow through the second inlet 303b and the gas outlet 303c (i.e., discharging the reference gas RG from the gas outlet 303c), and alternately fills the sampling space SS' of the filling section 301 with the sample gas SG and the reference gas RG. By providing the introduction section 303, it is possible to realize a cross-flow modulation type analytical device 200 in which the sample gas SG and the reference gas RG are alternately filled into the sampling space SS' of the filling section 301.

The analysis device 200 further includes a control unit 307. The control unit 307 is a computer system including a CPU, a storage device (e.g., a storage device such as a RAM or a ROM), and various interfaces. The control unit 307 may be a system including each of the above devices individually, or may be a SoC (System on Chip) in which the above devices are integrated on a single chip.
The control unit 307 controls the irradiation unit 301a and the introduction unit 303 of the analysis device 200. In addition, the control unit 307 may be capable of controlling the operation and stopping of the first pump 304b and the boost pump 305a and/or the flow rate.

In addition, the control unit 307 controls the irradiation unit 301a to irradiate the measurement light L' into the sampling space SS' of the filling unit 301, and analyzes the gas to be measured based on the intensity of the measurement light L' that passes through the sampling space SS' and is detected by the detection unit 301b.

(3) Operation of the Analytical Apparatus According to the Second Embodiment (3-1) Analytical Operation The following describes the operation of the analytical apparatus 200 according to the second embodiment. Specifically, the analytical operation in the analytical apparatus 200 will be described with reference to FIG. 7. FIG. 7 is a flowchart showing the analytical operation of the analytical apparatus according to the second embodiment. In this embodiment, the analytical apparatus 200 performs analysis of the measurement target gas by the cross-flow modulation method. Note that the operations described below are performed by the control unit 307 controlling the analytical apparatus 200. In addition, prior to the following analytical operations, calibration (e.g., zero calibration, span calibration) of the analytical apparatus 200 is performed at predetermined intervals (e.g., one week).

When the analysis operation of the gas to be measured is started, first, in step S201, the control unit 307 controls the introduction unit 303 to allow gas to flow through the second inlet 303b and the gas outlet 303c. As a result, the reference gas RG is supplied from the reference gas supply line 306 to the introduction unit 303, and the reference gas RG is introduced from the gas outlet 303c into the sampling space SS' of the filling unit 3. In other words, the sampling space SS' of the filling unit 3 is filled with the reference gas RG.

After the reference gas RG is filled into the sampling space SS' of the filling section 3, in step S202, the control section 307 outputs the measurement light L' from the irradiation section 301a, and the measurement light L' that passes through the sampling space SS' of the filling section 3 filled with the reference gas RG is detected by the detection section 301b. Based on the signal input from the detection section 301b, the control section 307 calculates the intensity (referred to as the analytical reference intensity) of the measurement light L' that passes through the sampling space SS' of the filling section 3 filled with the reference gas RG.

Next, in step S203, the control unit 307 controls the introduction unit 303 to allow gas to flow between the first inlet 303a and the gas outlet 303c. This allows the sample gas SG to be introduced from the gas outlet 303c into the sampling space SS' of the filling unit 3. In other words, the sampling space SS' of the filling unit 3 is filled with the sample gas SG.

After the sample gas SG is filled into the sampling space SS' of the filling section 3, in step S204, the control section 307 causes the irradiation section 301a to output the measurement light L', and the detection section 301b detects the measurement light L' that has passed through the sampling space SS' of the filling section 3 filled with the sample gas SG. Based on the signal input from the detection section 301b, the control section 307 calculates the intensity (referred to as the analysis intensity) of the measurement light L' that has passed through the sampling space SS' of the filling section 3 filled with the sample gas SG.

Furthermore, in step S205, the control unit 307 analyzes the measurement target gas contained in the sample gas SG based on the difference between the analysis intensity calculated in step S204 and the analysis standard intensity calculated in step S202. Specifically, the concentration of the measurement target gas is calculated from the difference between the analysis intensity and the analysis standard intensity.

6, the reference gas RG is generated from the sample gas SG using the measurement target removal unit 302. This eliminates the need to provide a gas cylinder for the reference gas RG. As a result, the burden on the user due to the need to replace the gas cylinder can be reduced.

In addition, in the measurement target removal unit 302 having the above-mentioned gas separation membrane (hollow fiber membrane), the ability to separate nitrogen gas and oxygen gas from air is maintained for a long period of time, so replacement of the measurement target removal unit 302 is almost unnecessary. As a result, the burden on the user can be reduced.

6, for example, there is no need to switch between multiple removal units to remove the gas to be measured, so there is no need to form a complex gas path for switching between multiple removal units. In this way, the gas path of the analysis device 200 can be simplified, and the number of parts used in the analysis device 200 can be reduced.

(4) Modification 1 of the analysis device according to the second embodiment
(4-1) Overview of Modification 1 In the analytical device 200 described above, the measurement target removal unit 302 is connected to a branch line 305 branched off from the exhaust flow path 304, and removes the measurement target gas from the sample gas SG to generate the reference gas RG. In other words, the reference gas generation gas for generating the reference gas RG is the sample gas SG.
However, the reference gas generation gas is not limited to the sample gas SG. As shown in FIG. 8, the analysis apparatus according to the second embodiment (analysis apparatus 200') further includes an air supply unit 309 that supplies pressurized air AR', and the air supply unit 309 is connected to the measurement target removal unit 302 by an air supply line 309a. That is, in the analysis apparatus 200', the reference gas generation gas is air AR' supplied from a supply source (air supply unit 309) different from the sample gas SG. FIG. 8 is a diagram showing the configuration of the analysis apparatus according to the second embodiment.

In this way, by supplying the reference gas generation gas supplied to the measurement target removal unit 302 from the air supply unit 309, which is a supply source different from the sample gas SG, it is possible to supply sufficiently pressurized air AR' to the measurement target removal unit 302 as reference gas generation gas without providing a pressure boosting pump 305a. In other words, the conditions of the reference gas generation gas supplied to the measurement target removal unit 302 can be set to appropriate conditions that allow the measurement target removal unit 302 to fully demonstrate its performance.

As in the second embodiment described above, a regulator 309b is provided between the air supply unit 309 and the measurement target removal unit 302. The regulator 309b keeps the pressure of the sample gas SG supplied from the air supply unit 309 to the measurement target removal unit 302 constant.

In the analytical apparatus 200' relating to variant example 1, the state of the measurement target gas removal ability of the measurement target removal section 302, i.e., the deterioration state of the measurement target removal section 302, can be confirmed based on a comparison between the intensity of the measurement light L' when the filling section 3 is filled with the reference gas RG supplied from the measurement target removal section 302 and the intensity of the measurement light L' when the filling section 3 is filled with, for example, a gas used for zero calibration (for example, nitrogen gas supplied from a gas cylinder).
In the analysis device 200' according to the first modification, the deterioration state of the measurement target removal unit 302 is determined by a control unit 307' of the analysis device 200'. The other configurations and functions of the analysis device 200' are the same as those of the analysis device 200 according to the second embodiment, and therefore will not be described here.

(4-2) Configuration of the Control Unit According to Modification 1 Hereinafter, a specific configuration of the control unit 307' according to modification 1 that can determine the state of deterioration of the measurement target removal unit 302 will be described with reference to FIG. 9. FIG. 9 is a diagram showing a specific configuration of the control unit according to modification 1. The control unit 307' mainly has an analysis unit 307a, a determination unit 307b, and a notification unit 307c. Note that some or all of the functions of the above-mentioned units of the control unit 307' are realized by executing a program stored in a storage device of the computer system that constitutes the control unit 307. Also, some of the functions of the above-mentioned units may be realized by hardware.

The analysis unit 307a performs an analysis of the measurement target gas contained in the sample gas SG. The analysis operation of the measurement target gas performed by the analysis unit 307a is the same as the operation of the control unit 307 in the second embodiment described above, so a description thereof will be omitted here.

The determination unit 307b determines the deterioration of the measurement target removal unit 302. The determination unit 307b determines whether the measurement target removal unit 302 has deteriorated based on a comparison between the intensity of the measurement light L' obtained when the reference gas RG is filled into the sampling space SS' of the filling unit 3 and the intensity of the measurement light L' obtained when the sampling space SS' is filled with a zero gas (e.g., nitrogen gas supplied from a gas cylinder) that contains almost no measurement target gas and is used for zero calibration of the analysis device.

If the measurement target removal unit 302 is not deteriorated, the content of the measurement target gas contained in the reference gas RG is close to the content of the measurement target gas in the zero gas. Therefore, the intensity of the measurement light L' obtained when the reference gas RG is filled into the sampling space SS' of the filling unit 3 is approximately the same as the intensity of the measurement light L' obtained when the zero gas is filled into the sampling space SS' of the filling unit 3.

On the other hand, when the measurement target removal unit 302 is deteriorated, the ability to remove the measurement target gas from the reference gas generation gas (air AR in this embodiment) decreases, and the measurement target gas becomes included in the reference gas RG. As a result, the measurement light L' that passes through the sampling space SS' filled with the reference gas RG is absorbed by the measurement target gas contained in the reference gas RG, and the intensity of the measurement light L' obtained when the reference gas RG is filled becomes smaller than the intensity of the measurement light L' obtained when the zero gas is filled.

Using the above principle, the judgment unit 307b can judge that the measurement target removal unit 302 has deteriorated if the intensity of the measurement light L' obtained when the reference gas RG is filled into the sampling space SS' of the filling unit 3 is lower than the intensity of the measurement light L' obtained when the zero gas is filled into the sampling space SS' of the filling unit 3 by a predetermined intensity or more.
If the determining unit 307b determines that the measurement target removal unit 302 has deteriorated, it notifies the notification unit 307c of the determination result.

When the determination unit 307b receives a determination result that the measurement target removal unit 302 is degraded, the notification unit 307c notifies that the measurement target removal unit 302 is degraded. Specifically, when the notification unit 307c determines that the measurement target removal unit 302 is degraded, it outputs a signal to operate the alarm device 308. The alarm device 308 is, for example, a device that emits sound (speaker), a warning light, a device that displays an image on a screen (display), etc. In this way, the alarm device 308 is a device that notifies information output from the analysis device 200.

The alarm device 308 can be a separate device from the analysis device 200, forming an analysis system. By making the alarm device 308 and the analysis device 200 separate devices, for example, the alarm device 308 can be installed in a location different from the location where the analysis device 200 is installed.

(4-3) Operation for Determining Deterioration of the Measurement Target Removal Unit Next, the operation for determining deterioration of the measurement target removal unit 302 in the analysis device 200' according to Modification 1 will be described with reference to Fig. 10. Fig. 10 is a flow chart showing the operation for determining deterioration of the measurement target removal unit in the analysis device according to Modification 1 of the second embodiment. Note that the operation described below is executed by the determination unit 307b controlling the analysis device 200.
First, in step S301, the sampling space SS' of the filling unit 3 is filled with zero gas (for example, nitrogen gas) using a gas cylinder or the like for zero gas.
Then, in step S302, the measurement light L' is output from the irradiation unit 301a, and the measurement light L' that passes through the sampling space SS' of the filling unit 3 filled with zero gas is detected by the detection unit 301b. Based on the signal input from the detection unit 301b, the intensity of the measurement light L' that passes through the sampling space SS' of the filling unit 3 filled with zero gas is calculated.

Next, in step S303, the reference gas RG from which the measurement target gas has been removed by the measurement target removal unit 302 is filled into the sampling space SS' of the filling unit 3. Specifically, the introduction unit 303 is controlled to allow gas to flow between the second inlet 303b and the gas outlet 303c, and the reference gas RG is filled into the sampling space SS'.
Thereafter, in step S304, the measurement light L' is output from the irradiation unit 301a, and the measurement light L' that has passed through the sampling space SS' of the filling unit 3 filled with the reference gas RG is detected by the detection unit 301b. Based on the signal input from the detection unit 301b, the intensity of the measurement light L' that has passed through the sampling space SS' of the filling unit 3 filled with the reference gas RG is calculated.

After executing the above-mentioned step S304, in step S305, the judgment unit 307b judges whether or not the measurement target removal unit 302 has deteriorated based on a comparison between the intensity of the measurement light L' that has passed through the zero gas obtained in step S302 and the intensity of the measurement light L' that has passed through the reference gas RG obtained in step S304.
For example, when the absolute value of the difference between the intensity of the measurement light L' that passed through the reference gas RG obtained in step S304 and the intensity of the measurement light L' that passed through the zero gas obtained in step S302 becomes equal to or greater than a predetermined value, it is determined that the reference gas RG contains a predetermined amount or more of the measurement target gas, and the measurement target removal unit 302 has deteriorated.

If the judgment unit 307b judges that the measurement target removal unit 302 is degraded ("Yes" in step S305), in step S306, the judgment unit 307b notifies the notification unit 307c of the judgment result that the measurement target removal unit 302 is degraded.
The notification unit 307c, which has received the determination result that the measurement target removal unit 302 has deteriorated, outputs a notification signal to the alarm device 308 to operate the alarm device 308. This makes it possible to notify the user that the measurement target removal unit 302 has deteriorated in a form that can be visually and/or audibly recognized by, for example, emitting a sound and/or turning on a warning light.
A user who recognizes that measurement object removal unit 302 has deteriorated can take measures such as replacing measurement object removal unit 302 .

On the other hand, if the judgment unit 307b does not judge that the measurement target removal unit 302 is degraded ('No' in step S305), the operation of judging the degradation of the measurement target removal unit 302 is terminated.

(5) Modification 2 of the analysis device according to the second embodiment
(5-1) Overview of the analytical apparatus according to variant example 2 In the analytical apparatus 200, 200' described above, only the measurement target removal section 302 was provided as a component for removing the measurement target gas from the sample gas SG or air AR' to generate the reference gas RG.
However, the present invention is not limited to this, and the second modification of the analyzer according to the second embodiment (analyzer 200'') may further include scrubbers 310a, 310b for removing the measurement target gas from the gas supplied from the measurement target removal unit 302, which is an _N2 separator, as shown in FIG. 11, and the gas from which the measurement target gas has been removed by the scrubbers 310a, 310b may be used as the reference gas RG. FIG. 11 is a diagram showing the configuration of the second modification of the analyzer according to the second embodiment. Note that the analyzer 200'' has the same configuration and function as the analyzer 200' according to the first modification, except for the inclusion of the scrubbers 310a, 310b, and therefore a description thereof will be omitted here.

(5-2) Scrubber The configuration of the scrubber in the analysis device 200'' according to the second modification will be described below with reference to FIG.
As shown in Fig. 11, the scrubbers 310a and 310b are components in which a moisture adsorbent S and a measurement target gas adsorbent Z are enclosed inside a purifier body 311. The moisture adsorbent S removes moisture from the gas supplied from the measurement target removal unit 302. The moisture adsorbent S has a property that the adsorbed components are released by heating to a predetermined regeneration temperature. As the moisture adsorbent S, for example , silica gel with regenerative adsorption ability is used, which releases physically adsorbed moisture by heating to a predetermined temperature.

The measurement target gas adsorbent Z further removes the measurement target gas from the gas supplied from the measurement target removal unit 302. The measurement target gas adsorbent Z may be, for example, zeolite, which has regenerative adsorption ability and releases the physically adsorbed measurement target gas by heating it to a predetermined temperature higher than that of silica gel.
Alternatively, for example, a molecular sieve can be used as the measurement target gas adsorbent Z. Such an adsorbent has, for example, many micropores and utilizes the molecular sieve effect to selectively adsorb only molecules that are large enough to enter the micropores. Unlike soda lime, which adsorbs molecules through chemical bonds, it has the characteristic of being easily regenerated by heating or the like.

The purifier body 311 is formed, for example, from a cylindrical metal member, and has an input port 311a at one end into which gas flows, and an output port 311b at the other end from which gas is discharged. The half of the purifier body 311 on the input port 311a side is filled with moisture adsorbent S, and the half on the output port 311b side is filled with measurement target gas adsorbent Z. At the boundary between the moisture adsorbent S and the measurement target gas adsorbent Z, for example, a filter mesh M is disposed as a partition.

The scrubbers 310a and 310b further include a heating mechanism 312. The heating mechanism 312 includes, for example, a wound heater that can be turned on and off by an external operation, and directly heats the measurement target gas adsorbent Z by winding the heater around the half of the output port 311b side of the purifier body 311. The moisture adsorbent S is indirectly heated by heat transfer from the purifier body 311, etc. The heating temperature by the heating mechanism 312 is set to be equal to or higher than the minimum regenerative temperature of the measurement target gas adsorbent Z, and equal to or higher than the regenerative temperature and equal to or lower than the decomposition temperature of the moisture adsorbent S. In this embodiment, the heating temperature by the heating mechanism 312 is, for example, 130°C to 180°C.

As shown in Fig. 11, an analysis device 200'' according to the second modification includes two scrubbers 310a and 310b arranged in parallel. Either of the two scrubbers 310a and 310b can be switched for use.
Specifically, the gas line GL1 connected to the outlet of the measurement target removal unit 302 branches into two gas lines GL2 and GL3. Of these two gas lines GL2 and GL3, the gas line GL2 is connected to the input port 311a of the scrubber 310a, and the gas line GL3 is connected to the input port 311a of 310b. In addition, a switching valve V1 (e.g., a three-way valve) is provided at the branching point of the gas lines. The switching valve V1 connects either one of the two scrubbers 310a and 310b to the measurement target removal unit 302 by switching between connecting the gas line GL1 to the gas line GL2 or connecting the gas line GL1 to the gas line GL3.

In addition, of the two branched gas lines GL2 and GL3, the gas line that is not connected to gas line GL1 (measurement target removal section 302) is connected to the purge gas exhaust line GL4 by a switching valve V2 (e.g., a three-way valve).

In the analytical apparatus 200'' having the above-described configuration, for example, when an analytical operation is performed with the switching valve V1 connecting the gas line GL1 and the gas line GL3 and the switching valve V2 connecting the gas line GL2 and the purge gas exhaust line GL4, the gas to be measured is removed by the scrubber 310b connected to the gas line GL3.
For example, if the ability of scrubber 310b to remove the target gas decreases, switching valve V1 connects gas line GL1 to gas line GL2, and switching valve V2 connects gas line GL3 to purge gas exhaust line GL4, thereby removing the target gas by unused or regenerated scrubber 310a.

In the above example, while scrubber 310a is being used, in scrubber 310b, whose removal capacity has decreased, regeneration of moisture adsorbent S and measurement target gas adsorbent Z is performed by heating using heating mechanism 312. This allows one scrubber to be regenerated while the other scrubber is being used.

By further providing the above-mentioned analytical device 200'' with scrubbers 310a, 310b that remove the target gas to be measured from the gas that has passed through the target gas removal section 302, it is possible to generate a reference gas RG having a lower content of the target gas to be measured and to extend the life of the scrubbers 310a, 310b.

(6) Summary of Second Embodiment The second embodiment described above can be summarized as follows.
In the analytical devices 200, 200', 200'' according to the second embodiment, the measurement target removal section 302 has a gas separation membrane that separates the measurement target gas from the reference gas generation gas (sample gas SG or air AR') to generate the reference gas RG. Since this gas separation membrane can be used for a long period of time, frequent replacement of the measurement target removal section 302 is not required. As a result, an increase in the burden on the user in analyzing the measurement target gas can be prevented.

In addition, since the measurement target removal section 302 has a long life, it is not necessary to configure the analytical devices 200, 200', 200'' in a complex manner, such as by switching between multiple gas lines to generate the reference gas RG, and control of the analytical devices 200, 200', 200'' can be simplified.

The analytical devices 200', 200'' are provided with a judgment unit 307b that judges the deterioration of the measurement target removal unit 302 based on the intensity of the measurement light L' that has passed through the sampling space SS' of the filling unit 301 filled with the reference gas RG, so that the deterioration state of the measurement target removal unit 302 can be easily judged by a method similar to the analysis of the measurement target gas based on the intensity of the measurement light L' that has passed through the gas filled in the filling unit 3.

The analysis devices 200, 200', 200'' are provided with a notification unit 307c that notifies the user that the measurement target removal unit 302 has been determined to be deteriorated, thereby allowing the user to be notified that the measurement target removal unit 302 has deteriorated.

The analytical devices 200, 200', 200'' are provided with an introduction section 303 that alternately introduces the sample gas SG and the reference gas RG into the sampling space SS' of the filling section 3, thereby realizing a cross-flow modulation type analytical device for the gas to be measured.

In the analytical device 200, by using the sample gas SG as the gas for generating the reference gas, a more appropriate reference gas RG can be generated from the sample gas SG to be measured.
In the analytical devices 200', 200'', by using air AR' supplied from a source (air supply section 309) different from the sample gas as the gas for generating the reference gas, the conditions of the gas for generating the reference gas supplied to the measurement target removal section 302 can be easily set to appropriate conditions that allow the performance of the measurement target removal section 302 to be fully demonstrated.

The analytical device 200'' further includes scrubbers 310a, 310b that remove the target gas from the gas that has passed through the target gas removal section 302, thereby making it possible to generate a reference gas RG having a lower target gas content and to extend the life of the scrubbers 310a, 310b.

Although several embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments, and various modifications are possible without departing from the gist of the invention. In particular, several embodiments and modifications described in this specification can be arbitrarily combined as necessary.
(A) In the analysis device 100, 100' according to the first embodiment, the first mirror 71a, the second mirror 71b, the third mirror 71c, the fourth mirror 71d, the fifth mirror 71e, and the sixth mirror 71f are arranged in the propagation space TS. The arrangement of these mirrors may be changed depending on the positional relationship between the light sources 51a to 51d and the filling unit 3 inside the housing 1.
For example, if the distance between the light sources 51a to 51d and the filling section 3 becomes shorter as a result of the distance from the light sources 51a to 51d through which the measurement light L propagates in the propagation space TS to the filling section 3 becoming shorter, the number of mirrors in the propagation space TS may be reduced, or no mirrors may be provided in the propagation space TS.

(B) When determining deterioration of the measurement target removal unit 9 in the analytical device 100, 100' of the first embodiment, the purge gas PG generated by the measurement target removal unit 9 may be filled into the sampling space SS of the filling unit 3, and the deterioration of the measurement target removal unit 9 may be determined based on the intensity of the measurement light L that has passed through the purge gas PG in the sampling space SS.
As described in the first embodiment, the optical path length of the measurement light L in the sampling space SS is long due to multiple reflections, so that the low concentration of the target gas contained in the purge gas PG can be accurately measured based on the intensity of the measurement light L that has passed through the purge gas PG in the sampling space SS.

In addition, by filling the sampling space SS with purge gas PG, even if the sampling space SS is contaminated by use, the intensity of the measurement light L can be measured while including the influence of contamination. As a result, the content of the measurement target gas contained in the purge gas PG can be measured with greater accuracy.

(C) In the analysis device 100, 100' according to the first embodiment, a cell filled with a gas that has a configuration similar to that of the filling section 3 and does not contain a measurement target gas such as nitrogen gas may be provided separately, and the measurement light L may be passed through this cell when determining deterioration of the measurement target removal section 9. This allows accurate measurement of only the amount of absorption of the measurement light L by the measurement target gas contained in the purge gas PG in the propagation space TS, without being affected by contamination of the filling section 3.

(D) In addition, in the analysis device 100, 100' according to the first embodiment and the analysis device 200, 200' according to the second embodiment, a disposable remover made of porous calcium hydroxide, a coloring agent, and silver nitrate may be used to remove the target gas contained in the gas. This makes it possible to achieve stable measurements at low cost.

(E) In the analysis device 100, 100' according to the first embodiment, the measurement target removal unit 9 generates a purge gas from air supplied from the air supply line 11. However, this is not limited to this, and instead of the air supply line 11, for example, a cylinder filled with a gas containing oxygen and nitrogen may be connected to the measurement target removal unit 9, and the measurement target removal unit 9 may extract nitrogen from the gas supplied from the cylinder to generate a purge gas.

The present invention can be widely applied to analytical devices that analyze the target gas contained in a sample gas.

100, 100' Analytical device 1 Housing 11 Air supply line 11a First air supply line 11b Second air supply line 11c Three-way valve 12 Air supply section 13 Outlet IS Internal space 3 Filling section 31 Inlet 32 Outlet 33a First reflecting member 33b Second reflecting member SS Sampling space 5 Irradiation sections 51a to 51d Light sources L1 to L4 Element light 7 Propagation section 71a First mirror 71b Second mirror 71c Third mirror 71d Fourth mirror 71e Fifth mirror 71f Sixth mirror 75 Detection section 77 Purge gas supply line 79 Purge gas outlet TS Propagation space 9 Measurement target removal section 20 Control section 201 Analysis section 203 First determination section 205 Notification section 207 Second determination section 30 Notification device F Flange W Optical window PG Purge gas PR1 Pressure gauge AR Air L Measurement light 200, 200', 200'' analysis device 301 Filling section 301a Irradiation section 301b Detection section SS' Sampling space 302 Measurement target removal section 303 Introduction section 303a First inlet 303b Second inlet 303c Gas outlet 304 Discharge flow path 304a Orifice 304b First pump 305 Branch line 305a Booster pump 305b Regulator 306 Reference gas supply line 307 Control section 307a Analysis section 307b Determination section 307c Notification section 308 Notification device 309 Air supply section 309a Air supply line 309b Regulators 310a, 310b Scrubber AR' Air L' Measurement light RG Reference gas SG Sample gas

Claims (12)

An analytical apparatus for analyzing a measurement target gas, comprising:
a filling section into which a sample gas containing the gas to be measured is filled;
an irradiation unit that irradiates a measurement light toward the filling unit;
a propagation section provided between the filling section and the irradiation section and forming a propagation space through which the measurement light propagates;
a measurement target removal unit having a gas separation membrane that removes the measurement target gas from air supplied from an air supply line and generates a purge gas for purging the propagation space;
a housing that stores the filling unit, the irradiation unit, the propagation unit, and the measurement target removal unit in an internal space and isolates the internal space from an external space;
Equipped with
the propagation section has a purge gas exhaust port that exhausts the purge gas introduced into the propagation space into an internal space of the housing,
The air supplied from the air supply line is supplied to the internal space of the housing.
Analytical equipment. a detection unit that detects the measurement light that has passed through the propagation space purged by the purge gas;
a first determination unit that determines deterioration of the measurement target removal unit based on an intensity of the measurement light absorbed by the measurement target gas and a gas that affects the measurement light by passing through the propagation space;
The analysis device of claim 1 further comprising: The analyzer according to claim 1 or 2, further comprising a second determination unit that determines deterioration of the measurement target removal unit based on the pressure or flow rate of the air supplied to the measurement target removal unit. The analysis device according to claim 2 or 3, further comprising a notification unit that notifies that the measurement target removal unit is determined to be degraded. The analytical device according to any one of claims 1 to 4, wherein the gas separation membrane separates nitrogen gas from the air as the purge gas. The analytical device according to any one of claims 1 to 5, wherein the gas to be measured is carbon dioxide, carbon monoxide, methane, sulfur dioxide, ammonia, nitrogen oxides, hydrogen chloride, water, ethane, acetylene, propane, ethylene, hexane, propylene, hydrogen sulfide, isobutene, methanol, phosgene, butane, chloroethylene, methyl nitrite, cyclohexane, butadiene, isobutane, isopentane, toluene, hydrogen, hydrogen fluoride, or trifluoropropene. An analysis system comprising an analysis device according to any one of claims 1 to 6 and an alarm device that alarms information output from the analysis device. 1. An analytical apparatus for analyzing a gas to be measured based on an intensity of a measurement light passing through a sample gas containing the gas to be measured and an intensity of the measurement light passing through a reference gas used as a standard for analysis of the gas to be measured, comprising:
a filling section into which a gas containing the sample gas or the reference gas is filled;
an irradiation unit that irradiates the measurement light toward the filling unit;
a measurement target removal unit having a gas separation membrane that separates the measurement target gas from air supplied from a supply source different from the sample gas ;
a scrubber that removes the measurement target gas from the gas supplied from the measurement target removal unit to generate the reference gas;
An analytical device comprising: The analytical device according to claim 8, further comprising an introduction section that alternately introduces the sample gas and the reference gas into the filling section. a detection unit that detects the measurement light that has passed through the filling unit;
a determination unit that determines deterioration of the measurement target removal unit based on the intensity of the measurement light that has passed through the filling unit filled with the reference gas; and
The analytical device of claim 9 further comprising: The analysis device according to claim 10, further comprising a notification unit that notifies that the measurement target removal unit is determined to be degraded. The analytical device according to any one of claims 8 to 11, wherein the gas to be measured is carbon dioxide, carbon monoxide, methane, sulfur dioxide, ammonia, nitrogen oxides, hydrogen chloride, water, ethane, acetylene, propane, ethylene, hexane, propylene, hydrogen sulfide, isobutene, methanol, phosgene, butane, chloroethylene, methyl nitrite, cyclohexane, butadiene, isobutane, isopentane, toluene, hydrogen, hydrogen fluoride, or trifluoropropene.

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