Infrared gas analyzer, infrared gas analyzing method, and concentration calculation program

Abstract

To detect two components in which infrared absorption wavelength regions are overlapped to each other by one detector.SOLUTION: An infrared gas analyzer includes an infrared light source 3, an infrared detector 4 for detecting infrared rays having passed through a sample, and a device 6 for calculating concentrations of a first measurement component contained in the sample and a second measurement component interfering with the first measurement component, wherein the infrared detector 4 is a pneumatic detector, and has a gas chamber 41 for measurement of the first measurement component, a gas chamber 42 for interference of the second measurement component, a first sensor 41x for detecting pressure change according to infrared absorption of gas for measurement, and a second sensor 42x for detecting pressure change according to infrared absorption of gas for interference, and the calculation device 6 has a first calculation part 63 for calculating the concentration of the first measurement component using output of the first sensor 41x and output of the second sensor 42x, and a second calculation part 64 for calculating the concentration of the second measurement component using output of the second sensor 42x.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an infrared gas analyzer, an infrared gas analysis method, and a concentration calculation program. [Background technology]

[0002] Infrared gas analyzers are used as devices for measuring the concentration of components in exhaust gases. As shown in Patent Document 1, this type of infrared gas analyzer includes a non-dispersive infrared absorption type (NDIR analyzer).

[0003] When using this type of NDIR analyzer to detect a measurement component such as dinitrogen monoxide (N2O), the infrared absorption wavelength range of NO overlaps with that of carbon monoxide (CO), making CO an interference component with NO. For this reason, the CO in the sample is oxidized to carbon dioxide (CO2) using an oxidation catalyst to reduce the interference effect of CO.

[0004] However, this type of NDIR analyzer can calculate the concentration of N2O, but cannot calculate the concentration of CO because CO is oxidized to CO2 to reduce the interference effect. As a result, the concentrations of N2O and CO cannot be measured with one NDIR analyzer. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2013-96889 A Summary of the Invention [Problem to be solved by the invention]

[0006] Therefore, the present invention has been made to solve the above-mentioned problems, and its main objective is to measure two components whose infrared absorption wavelength ranges overlap with each other using a single infrared gas analyzer. [Means for solving the problem]

[0007] That is, the infrared gas analyzer according to the present invention comprises an infrared light source which irradiates a sample with infrared rays, an infrared detector which detects the infrared rays transmitted through the sample, and a calculation device which calculates the concentrations of a first measurement component contained in the sample and a second measurement component which is a measurement component that interferes with the first measurement component using the output of the infrared detector, the infrared detector being a pneumatic detector, and having a measurement gas chamber in which a measurement gas based on the infrared absorption characteristics of the first measurement component is sealed and into which the infrared rays that have passed through the sample are incident, an interference gas chamber in which an interference gas based on the infrared absorption characteristics of the second measurement component is sealed and into which the infrared rays that have passed through the sample are incident, a first sensor which detects a pressure change corresponding to the infrared absorption of the measurement gas, and a second sensor which detects a pressure change corresponding to the infrared absorption of the interference gas, the calculation device having a first calculation unit which calculates the concentration of the first measurement component using the output of the first sensor and the output of the second sensor, and a second calculation unit which calculates the concentration of the second measurement component using the output of the second sensor.

[0008] According to this configuration, there is provided a first sensor that detects a pressure change corresponding to infrared absorption by the measurement gas, and a second sensor that detects a pressure change corresponding to infrared absorption by the interference gas. The calculation device calculates the concentrations of the first and second measurement components based on the outputs of these sensors, so that the concentrations of the first and second measurement components can be measured by a single infrared detector.

[0009] It is desirable that the second calculation unit calculates the concentration of the second measurement component using the output of the second sensor and the output of the first calculation unit.

[0010] In this configuration, the second calculation unit calculates the concentration of the second measurement component using the output of the second sensor and the output of the first calculation unit, so that the concentration of the second measurement component is corrected by the concentration of the first measurement component calculated by the first calculation unit, and as a result, the concentration of the second measurement component can be calculated with higher accuracy.

[0011] When the calculation device calculates the concentration of the first measurement component and the concentration of the second measurement component, the outputs of the first sensor and the second sensor may change depending on the concentration of carbon dioxide (CO2) contained in the sample, resulting in a measurement error. In order to prevent this measurement error, it is desirable that the infrared gas analyzer further includes a CO2 measuring unit that detects carbon dioxide contained in the sample, and that the calculation device corrects the concentration of the first measured component or the concentration of the second measured component using the CO2 concentration obtained by the CO2 measuring unit.

[0012] With this configuration, when the calculation device calculates the concentration of the first measured component and the concentration of the second measured component, the concentration of the first measured component or the concentration of the second measured component is corrected using the concentration of CO2 obtained by the CO2 measurement unit, thereby reducing measurement errors corresponding to the concentration of CO2.

[0013] In the infrared gas analyzer of the present invention, it is desirable that the first measurement component is carbon monoxide (CO) and the second measurement component is nitrous oxide (N2O).

[0014] With this configuration, it is possible to detect carbon monoxide and nitrous oxide, which are two components whose infrared absorption wavelength ranges overlap, with a single infrared detector. Since nitrous oxide is a greenhouse gas that causes global warming, the infrared gas analyzer of the present invention can be suitably used in industrial fields where reduction in environmental load is required.

[0015] The infrared gas analyzer of the present invention preferably further comprises two infrared detectors, and the first and second measurement components in one of the infrared detectors are nitric oxide (NO) and water (H2O), respectively, and the first and second measurement components in the other infrared detector are sulfur dioxide (SO2) and methane (CH4), respectively.

[0016] With this configuration, the calculation device calculates the NO concentration using the NO and H2O detected by one of the infrared detectors, and calculates the SO2 or CH4 concentration using the SO2 and CH4 detected by the other infrared detector, so that the infrared gas analyzer of the present invention can simultaneously measure five components contained in a sample, namely N2O, NO, CO, CO2, SO2, and CH4.

[0017] The infrared gas analyzer of the present invention further comprises a gas filter containing a plurality of components other than the first measurement component and the second measurement component, and it is preferable that the gas filter contains a plurality of components that do not react with each other or a plurality of components that are stable in an equilibrium state with each other.

[0018] With this configuration, since the gas filter contains multiple components other than the first and second measurement components in the sample, it is possible to eliminate the need for a catalyst that oxidizes or reduces at least one of the multiple second measurement components, and as a result, it is possible to reduce running costs.

[0019] It is desirable that the calculation device calculates the concentrations of the first and second measured components by subtracting the CO2 concentration obtained by the CO2 measuring unit multiplied by a predetermined weighting coefficient from the outputs of the first and second sensors, and changes or corrects the weighting coefficient based on the CO2 concentration.

[0020] With this configuration, the calculation device changes or corrects the weighting coefficient based on the CO2 concentration, thereby reducing the measurement error that occurs when the weighting coefficient is constant, and the first and second measurement components can be measured accurately regardless of the CO2 concentration.

[0021] Further, an infrared gas analysis method according to the present invention is an infrared gas analysis method used in an infrared gas analyzer that irradiates a sample with infrared rays and detects the infrared rays transmitted through the sample with an infrared detector to analyze a first measurement component in the sample and a second measurement component that interferes with the first measurement component, the infrared gas analyzer having the infrared detector which is a pneumatic detector, a measurement gas chamber in which a measurement gas based on the first measurement component is sealed and into which the infrared rays that have passed through the sample are incident, and an interfering gas chamber in which an interfering gas based on the second measurement component is sealed and into which the infrared rays that have passed through the sample are incident, the infrared gas analysis method is characterized in that it detects a pressure change in response to infrared absorption of the measurement gas, detects a pressure change in response to infrared absorption of the interfering gas, calculates a concentration of the first measurement component using the pressure change in response to infrared absorption of the measurement gas and the pressure change in response to infrared absorption of the interfering gas, and calculates a concentration of the second measurement component using the pressure change in response to infrared absorption of the interfering gas. Further, the present invention provides a concentration calculation program for use in an infrared gas analyzer including an infrared light source for irradiating a sample with infrared rays, an infrared detector for detecting infrared rays transmitted through the sample, and a calculation device for calculating the concentrations of a first measurement component contained in the sample and a second measurement component that interferes with the first measurement component using the output of the infrared detector, the infrared gas analyzer including the infrared detector being a pneumatic detector, a measurement gas chamber in which a measurement gas based on the first measurement component is sealed and into which the infrared rays that have passed through the sample are incident, an interference gas chamber in which an interference gas based on the second measurement component is sealed and into which the infrared rays that have passed through the sample are incident, a first sensor for detecting a pressure change corresponding to infrared absorption of the measurement gas, and a second sensor for detecting a pressure change corresponding to infrared absorption of the interference gas, the concentration calculation program being characterized in that it provides a computer with a function for calculating the concentration of the first measurement component using the output of the first sensor and the output of the second sensor, and a function for calculating the concentration of the second measurement component using the output of the second sensor. Effect of the Invention

[0022] According to the present invention thus configured, two components whose infrared absorption wavelength ranges overlap can be detected by one detector. [Brief description of the drawings]

[0023] [Figure 1] 1 is a schematic diagram showing an infrared gas analyzer according to an embodiment of the present invention; [Diagram 2] FIG. 4 is a diagram showing infrared absorption spectra of each component according to the embodiment. [Diagram 3] FIG. 13 is a schematic diagram showing an infrared gas analyzer according to a modified embodiment. [Figure 4] FIG. 11 is a diagram showing infrared absorption spectra of each component according to a modified embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] An embodiment of an infrared gas analyzer according to the present invention will be described below with reference to the drawings. In any of the drawings shown below, some parts may be omitted or exaggerated in schematic form for ease of understanding. The same components are denoted by the same reference numerals and the description thereof will be omitted.

[0025] The infrared gas analyzer 100 according to this embodiment detects nitrous oxide (NO), nitrogen oxides (NO) and the like in a sample such as exhaust gas (flue gas) emitted from industrial facilities such as sewage treatment plants, wastewater treatment plants, industrial waste treatment plants, and chemical plants. X It measures the concentrations of components such as sulfur dioxide (SO2), carbon monoxide (CO), carbon dioxide (CO2), and methane (CH4) using non-dispersive infrared absorption (NDIR).

[0026] Specifically, the infrared gas analyzer 100 measures the concentrations of CO and NO in a sample, and as shown in FIG. 1, includes a measurement cell 2 into which the sample is introduced, an infrared light source 3 provided at one end of the measurement cell 2 and irradiating the measurement cell 2 with infrared rays, an infrared detector 4 provided at the other end of the measurement cell 2 and detecting the infrared rays that have passed through the measurement cell 2, a CO2 measurement unit 5 that measures carbon dioxide in the sample, and a calculation device 6 that acquires outputs from the infrared detector 4 and the CO2 measurement unit 5 and calculates the concentrations of a first measurement component (CO) and a second measurement component (N2O), which is a measurement component that interferes with the first measurement component.

[0027] The measurement cell 2 has, for example, a roughly cylindrical shape, and both ends thereof are sealed by cell window members 2a, 2b made of an infrared-transparent material. An introduction port P1 for introducing a sample into the cell and an outlet port P2 for discharging the sample to the outside of the cell are provided on the side wall.

[0028] The infrared light source 3 is provided facing the cell window member 2a on one end side of the measurement cell 2, and irradiates infrared rays into the inside of the measurement cell 2. An optical chopper (not shown) is provided between the infrared light source 3 and the measurement cell 2, and is configured to be rotated by, for example, a motor to chop the infrared rays generated by the infrared light source 3 at a constant cycle.

[0029] The infrared detector 4 is provided facing the cell window member 2b at the other end side of the measurement cell 2, and is, for example, a condenser microphone type pneumatic detector. Specifically, the infrared detector 4 has a measurement gas chamber 41 in which a measurement gas based on the infrared absorption characteristics of the first measurement component (CO) is sealed and into which infrared rays passing through the sample are incident, and an interference gas chamber 42 in which an interference gas based on the infrared absorption characteristics of the second measurement component (N2O) is sealed and into which infrared rays passing through the sample are incident. The measurement gas chamber 41 and the interference gas chamber 42 are optically arranged in series in this order from the other end side of the measurement cell 2.

[0030] The measurement gas chamber 41 is made of a body block made of a corrosion-resistant metal, both ends of which are sealed with window members made of an infrared-transmitting material, and a first sensor 41x is disposed inside the body block. A first measurement component (CO) or a measurement gas exhibiting infrared absorption characteristics equivalent thereto is sealed inside the measurement gas chamber 41, and the first sensor 41x detects a pressure change corresponding to the infrared absorption spectrum of the first measurement component (CO). The first sensor 41x of this embodiment is sensitive to both the first measurement component and the second measurement component.

[0031] In this embodiment, since the first measurement component is CO, a predetermined concentration of CO gas is sealed in the measurement gas chamber 41. As a result, the first sensor 41x detects a pressure change corresponding to the infrared absorption spectrum of CO (see FIG. 2).

[0032] The interference gas chamber 42 is made of a body block made of a corrosion-resistant metal, both ends of which are sealed by window members made of an infrared-transmitting material, and a second sensor 42x is disposed inside the body block. The interference gas chamber 42 is filled with a second measurement component (N2O) or an interference gas having an equivalent infrared absorption characteristic, and the second sensor 42x detects a pressure change corresponding to the infrared absorption spectrum of the second measurement component. The interference gas chamber 42 is provided at the rear of the measurement gas chamber 41, and is sensitive to the second measurement component because CO is mostly absorbed in the measurement gas chamber 41.

[0033] In this embodiment, in order to correct the interference effect of NO on CO, the interference gas chamber 42 is filled with CO gas having a higher concentration than the CO gas in the measurement gas chamber 41. As a result, the interference gas chamber 42 detects the intensity of infrared rays in a wavelength range that matches the infrared absorption spectrum of NO (see FIG. 2).

[0034] Furthermore, in this embodiment, in order to reduce the interference effect of components such as SO2 and CH4 in the sample, an optical filter 8 is provided to narrow the wavelength of infrared light detected by the infrared detector 4. This optical filter 8 transmits infrared light in the absorption wavelength range of CO and NO, and specifically, the optical filter 8 transmits, for example, a wavelength range of 4 μm to 5 μm. The optical filter 8 in this embodiment is provided between the measurement cell 2 and the infrared detector 4.

[0035] The CO2 measuring unit 5 measures CO2 in a sample. Specifically, the CO2 measuring unit 5 has a CO2 measuring cell 51 into which a sample is introduced, an infrared ray irradiating unit 52 that irradiates infrared rays to the CO2 measuring cell 51, and a CO2 detector 53 that detects infrared rays transmitted through the CO2 measuring cell 51. In this embodiment, the sample that has passed through the CO2 measuring cell 51 is configured to be introduced into the measuring cell 2, but the opposite may be true.

[0036] The CO2 measuring cell 51 has the same configuration as the measuring cell 2 described above, but its cell length is shorter than that of the measuring cell 2 in accordance with the CO2 concentration. The CO2 detector 53 is, like the infrared detector 4 described above, a pneumatic detector of, for example, a condenser microphone type.

[0037] Here, the infrared irradiating section 52 is configured using the above-mentioned infrared light source 3 and a condensing member 7 provided between the infrared light source 3 and the measuring cell 2. The condensing member 7 is formed with a first optical path 7a consisting of a tapered inner wall surface that condenses infrared light. By passing through this first optical path 7a, the infrared light from the infrared light source 3 is condensed and irradiated to the measuring cell 2. In addition, a second optical path 7b for irradiating the infrared light to the CO2 measuring cell 51 is connected to the inner wall surface forming the first optical path 7a. Infrared light reflected by the tapered inner wall surface passes through this second optical path 7b, and the infrared light that has passed through the second optical path 7b is irradiated to the CO2 measuring cell 51.

[0038] The arithmetic device 6 calculates the CO concentration and the N2O concentration based on the output of the infrared detector 4 and the output of the CO2 measurement unit 5. The arithmetic device 6 can display the calculated measurement results of the CO concentration and the N2O concentration on a display unit 70 such as a display.

[0039] Specifically, the calculation device 6 includes a measurement preamplifier 61 that amplifies and outputs the output of the first sensor 41x, an interference preamplifier 62 that amplifies and outputs the output of the second sensor 42x, a first calculation unit 63 that calculates the concentration of the first measurement component using the output from the measurement preamplifier 61 and the output from the interference preamplifier 62, a second calculation unit 64 that calculates the concentration of the second measurement component using the output from the interference preamplifier 62, and a CO2 preamplifier 65 that amplifies and outputs the output of the CO2 detector 53.

[0040] The first calculation unit 63 includes a second measurement component removing unit 63a that removes the interference effect of the second measurement component on the first measurement component, and a first CO2 removing unit 63b that removes the interference effect of CO2 on the first measurement component. Specifically, the second measurement component removing unit 63a subtracts the output from the interference preamplifier 62 from the output from the measurement preamplifier 61. Furthermore, the first CO2 removing unit 63b subtracts the output from the CO2 preamplifier 65 from the output from the second measurement component removing unit 63a. As a result, the first calculation unit 63 can output the concentration of the first measurement component. Note that the first calculation unit 63 does not necessarily have to include the first CO2 removing unit 63b.

[0041] The second calculation unit 64 includes a second CO2 removal unit 64a that removes the interference effect of CO2 on the second measurement component, and a first measurement component removal unit 64b that removes the interference effect of the first measurement component on the second measurement component. Specifically, the second CO2 removal unit 64a subtracts the output from the CO2 preamplifier 65 from the output from the interference preamplifier 62. In addition, the first measurement component removal unit 64b subtracts the concentration of the first measurement component calculated by the first calculation unit 63 from the output of the second CO2 removal unit 64a. As a result, the second calculation unit 64 can output the concentration of the second measurement component. Note that the second calculation unit 64 does not necessarily have to include the second CO2 removal unit 64a.

[0042] <Effects of this embodiment> The infrared gas analyzer 100 of this embodiment configured as described above has a first sensor 41x that detects a pressure change corresponding to infrared absorption by the measurement gas, and a second sensor 42x that detects a pressure change corresponding to infrared absorption by the interference gas. The calculation device 6 calculates the concentrations of the first and second measurement components based on the outputs of these sensors, so that the concentrations of the first and second measurement components can be measured by a single infrared detector 4.

[0043] <Other embodiments> Although the first calculation unit 63 in the above embodiment removes the interference effect of the second measurement component and then removes the interference effect of CO2, the first calculation unit 63 may remove the interference effect of the second measurement component and then remove the interference effect of CO2. Specifically, the first calculation unit 63 may be configured to subtract the output from the CO2 preamplifier 65 from the output from the measurement preamplifier 61, and then subtract the output from the interference preamplifier 62.

[0044] Although the second calculation unit 64 in the above embodiment removes the interference effects of CO2 and the first measured component, the second calculation unit 64 does not have to remove these interference effects. That is, the second calculation unit 64 may directly calculate the concentration of the second measured component from the output of the interference preamplifier 62, and may not have to include the second CO2 removal unit 64a and the first measured component removal unit 64b.

[0045] In the above embodiment, the optical filter 9 is used to narrow the wavelength of infrared light detected by the infrared detector 4 in order to reduce the interference effects of components such as SO2 and CH4. However, the optical filter 9 does not necessarily have to be used.

[0046] The infrared gas analyzer of the above embodiment is of an optical chopping type in which an optical chopper is used to chop the infrared light from the infrared light source 3 at a constant period, but it may also be of a fluid modulation type in which a sample and a reference gas are alternately introduced into the measurement cell 2 at a constant period.

[0047] Furthermore, the infrared gas analyzer of the above embodiment measures the concentrations of CO, N2O, and CO2. X The concentration of other components such as SO2 and CH4 may be measured, or the concentration of two or more of these components may be measured.

[0048] An example of the configuration of an infrared gas analyzer 100 that measures the concentrations of, for example, four components is shown in Fig. 3. The infrared gas analyzer 100 shown in Fig. 3 measures the concentrations of, for example, five components, CO, NO, SO, CO, and NO, and further includes two infrared detectors in addition to the configuration of the above embodiment.

[0049] The first and second measurement components in one infrared detector 10 are nitric oxide (NO) and water (H2O), respectively. The first and second measurement components in the other infrared detector 11 are sulfur dioxide (SO2) and methane (CH4), respectively. These two infrared detectors 10 and 11 are, for example, condenser microphone type pneumatic detectors, similar to the above-mentioned infrared detector 4. With this configuration, as shown in FIG. 4, five components contained in a sample, that is, NO, NO, CO, CO2, SO2, or CH4, can be simultaneously measured by using the infrared detectors 10 and 11 for NO and H2O, SO2, and CH4, respectively, whose infrared absorption wavelength ranges overlap.

[0050] In addition, in this configuration example, the infrared rays that pass through the measurement cell 2 are split by a beam splitter 12 using half mirrors M1, M2, etc., to the infrared detector 4 (N2O detector), one infrared detector 10, and the other infrared detector 11.

[0051] As shown in Fig. 3, an optical filter 9 is also provided between the beam splitter 12 and the infrared detector 4 (N2O detector). Optical filters 13, 14 are also provided between the beam splitter 12 and the SO2 detector 101 and the NO detector 111. Furthermore, a gas filter may be provided between the beam splitter 12 and the infrared detectors 4, 10, 11 to remove the interference effect of the second measurement component on the first measurement component. Although Fig. 3 shows an example of a configuration for measuring the concentrations of five components, it is also possible to measure the concentrations of three or four components, or six or more components by changing the configuration of the beam splitter, for example.

[0052] The embodiment may further include a gas filter containing multiple components other than the first and second measurement components. Specifically, the gas filter is provided between the measurement cell 2 and the infrared detector 4, and reduces or removes the absorption spectrum of CO2 that interferes with the absorption spectrum of the first measurement component (CO) and the second measurement component (N2O). The gas filter contains CO2 gas in one chamber. The gas filter may further contain methane (CH4) as multiple components that do not react with CO2 or multiple components that are stable in equilibrium with CO2. The gas filter is provided between the measurement cell 2 and the infrared detector 4, but may be provided between the infrared light source 3 and the measurement cell 2, or may be built into the infrared light source 3 or the measurement cell 2.

[0053] Furthermore, the arithmetic device 6 of the above embodiment calculates the concentrations of CO and N2O by subtracting the output from the CO2 measuring unit 5, but may calculate the concentrations of the first and second measured components by subtracting the concentration of CO2 obtained by the CO2 measuring unit 5 multiplied by a predetermined weighting coefficient k from the outputs of the first sensor 41x and the second sensor 42x. Here, the weighting coefficient k is calculated in advance using a plurality of CO2 gases whose concentrations are known, and is stored in the arithmetic device 6. Then, during measurement, the weighting coefficient k is changed or corrected according to the output signal of the CO2 preamplifier 65 or the concentration of CO2 calculated therefrom.

[0054] In the above embodiment, exhaust gas discharged from an external combustion engine is analyzed, but exhaust gas discharged from an internal combustion engine of a vehicle, ship, or the like may also be analyzed.

[0055] In addition, various modifications and combinations of the embodiments may be made as long as they do not go against the spirit of the present invention. [Explanation of symbols]

[0056] 100···Infrared Gas Analyzer 2. Measurement cell 3. Infrared light source 4. Infrared detector 41....Measuring gas chamber 42. Interference gas chamber 41x... First sensing section 42x Second sensing section 5...CO2 measuring section 6...Arithmetic unit 7...Light collecting member 8. Optical filters

Claims

1. an infrared light source that irradiates the sample with infrared light; an infrared detector that detects infrared light transmitted through the sample; a calculation device that calculates the concentrations of a first measurement component contained in the sample and a second measurement component that is a measurement component that interferes with the first measurement component, using the output of the infrared detector; the infrared detector is a pneumatic detector; a measurement gas chamber in which a measurement gas based on the infrared absorption characteristics of the first measurement component is sealed and into which infrared light having passed through the sample is incident; an interference gas chamber in which an interference gas based on the infrared absorption characteristics of the second measurement component is sealed and into which the infrared light that has passed through the sample is incident; a first sensor for detecting a pressure change in response to infrared absorption by the measurement gas; a second sensor for detecting a pressure change in response to infrared absorption by the interference gas; The computing device a first calculation unit that calculates the concentration of the first measurement component using the output of the first sensor and the output of the second sensor; a second calculation unit that calculates the concentration of the second measurement component using the output of the second sensor.

2. 2. The infrared gas analyzer according to claim 1, wherein the second calculation unit calculates the concentration of the second measurement component using the output of the second sensor and the output of the first calculation unit.

3. The carbon dioxide (CO ２ ) to measure CO ２ Further comprising a measuring unit, The computing device ２ CO obtained by the measurement unit ２ 3. The infrared gas analyzer according to claim 1, wherein the concentration of the first measurement component or the concentration of the second measurement component is corrected using the concentration of the first measurement component or the concentration of the second measurement component.

4. The first measurement component is carbon monoxide (CO), and the second measurement component is nitrous oxide (N ２ 3. The infrared gas analyzer according to claim 1, wherein the first and second electrodes are substituted by the first electrode and the second electrode.

5. Further comprising two of said infrared detectors, The first and second measurement components in one of the infrared detectors are nitric oxide (NO) and water (H ２ O) The first measurement component and the second measurement component in the other infrared detector are sulfur dioxide (SO ２ ) and methane (CH ４ 5. The infrared gas analyzer according to claim 4, wherein

6. a gas filter containing a plurality of components other than the first and second measurement components; 3. The infrared gas analyzer according to claim 1, wherein the gas filter contains a plurality of components that do not react with each other or a plurality of components that are stable in equilibrium with each other.

7. The computing device calculates the CO ２ CO obtained by the measurement unit ２ The concentrations of the first and second measurement components are calculated by multiplying the concentration of the CO ２ 4. The infrared gas analyzer according to claim 3, wherein the weighting coefficients are changed or corrected based on the concentration of

8. 1. An infrared gas analysis method used in an infrared gas analyzer, which analyzes a first measurement component in the sample and a second measurement component that is a measurement component that interferes with the first measurement component by irradiating a sample with infrared rays and detecting the infrared rays that have transmitted through the sample with an infrared detector, comprising: The infrared gas analyzer comprises: the infrared detector being a pneumatic detector; a measurement gas chamber in which a measurement gas based on the first measurement component is sealed and into which infrared light having passed through the sample is incident; an interference gas chamber in which an interference gas based on the second measurement component is sealed and into which infrared light that has passed through the sample is incident; The infrared gas analysis method includes: detecting a pressure change in response to infrared absorption of the measurement gas; detecting a pressure change in response to infrared absorption by the interference gas; calculating a concentration of the first measurement component using a pressure change corresponding to infrared absorption of the measurement gas and a pressure change corresponding to infrared absorption of the interference gas; An infrared gas analysis method, wherein the concentration of the second measurement component is calculated using a pressure change corresponding to infrared absorption by the interfering gas.

9. A concentration calculation program for use in an infrared gas analyzer including an infrared light source that irradiates a sample with infrared rays, an infrared detector that detects the infrared rays that have passed through the sample, and a calculation device that calculates the concentrations of a first measurement component contained in the sample and a second measurement component that is a measurement component that interferes with the first measurement component, using an output from the infrared detector, The infrared gas analyzer comprises: the infrared detector being a pneumatic detector; a measurement gas chamber in which a measurement gas based on the first measurement component is sealed and into which infrared light having passed through the sample is incident; an interference gas chamber in which an interference gas based on the second measurement component is sealed and into which infrared light that has passed through the sample is incident; a first sensor for detecting a pressure change in response to infrared absorption by the measurement gas; a second sensor for detecting a pressure change in response to infrared absorption by the interference gas; The concentration calculation program a function of calculating the concentration of the first measurement component using the output of the first sensor and the output of the second sensor; and a function of calculating the concentration of the second measurement component using the output of the second sensor.

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