Gas measuring device and gas measurement method

Abstract

To provide a gas measuring device and a gas measurement method capable of measuring a specific gas without providing a pressure sensor in a reaction vessel in which pressure is changed.SOLUTION: A gas measuring device 5 includes: an absorbance measuring device 10 that applies detection light into a reaction vessel 2 for generating methane gas and measures absorbance of detection light passing through a gas atmosphere in the reaction vessel 2; an absorbance data analysis section 21 for performing a spectrum analysis of absorbance data measured by the absorbance measuring device 10; a peak detection section 22 for detecting multiple peak values from absorbance spectra analyzed by the absorbance data analysis section 21; and a pressure calculation section 23 for calculating pressure in the reaction vessel 2 on the basis of a ratio of strength of two points from among multiple peak values detected by the peak detection section 22.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a gas measurement device and a gas measurement method.

Background Art

[0002] The following Patent Document 1 discloses a laser that oscillates laser light with a wavelength and intensity corresponding to a drive current and temperature, a wavelength stabilization device that modulates the drive power of the laser at a predetermined temperature and with an arbitrary amplitude centered on a predetermined current value to stabilize the laser light at the center of an absorption line of a specific gas, a measurement gas cell that houses the specific gas to be measured and keeps the temperature of the specific gas constant, a photodetector that detects the intensity of transmitted light obtained by passing laser light with an arbitrary amplitude through the measurement gas cell, and a measurement means that performs phase-sensitive detection on a specific component in a signal from this detector and measures the concentration of the specific gas in the measurement gas cell from the change in the detection signal corresponding to the modulation amplitude.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, when focusing on one of the absorption spectral lines, methane gas and the like have an absorption coefficient that depends on the total atmospheric pressure. Therefore, when performing concentration measurement in a place where the atmospheric pressure changes drastically, such as a coal mine or a plant, if a pressure sensor is not provided separately to monitor the pressure and correction is not performed based on that value, accurate concentration measurement cannot be performed. In the above prior art, instead of providing a pressure sensor, a cell for measuring gas is installed which accommodates a specific gas to be measured and keeps the temperature of the specific gas constant, thereby solving the above problems. However, there is a problem that the installation of the cell for measuring gas is costly.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a gas measurement device and a gas measurement method capable of measuring a specific gas without providing a pressure sensor in a reaction vessel in which the pressure changes.

Means for Solving the Problems

[0006] A gas measurement device according to an aspect of the present invention includes an absorbance measurement device that irradiates detection light into a reaction vessel that generates gas and measures the absorbance of the detection light that has passed through the gas atmosphere in the reaction vessel, an absorbance data analysis unit that performs spectral analysis on the absorbance data measured by the absorbance measurement device, a peak detection unit that detects a plurality of peak values from the spectrum of the absorbance analyzed by the absorbance data analysis unit, and a pressure calculation unit that calculates the pressure in the reaction vessel based on the intensity ratio of two peak values among the plurality of peak values detected by the peak detection unit.

[0007] Further, in the gas measurement device according to an aspect of the present invention, a gas concentration calculation unit that calculates the concentration of the gas based on the peak value of the absorbance at a specific wavelength analyzed by the absorbance data analysis unit and the pressure in the reaction vessel calculated by the pressure calculation unit, and a gas concentration output unit that outputs the concentration of the gas calculated by the gas concentration calculation unit may be provided.

[0008] Further, the gas measurement device according to an aspect of the present invention may include a gas concentration output unit that outputs the concentration of the gas calculated by the gas concentration calculation unit.

[0009] Further, in the gas measurement device according to one aspect of the present invention, a data collation unit may be provided that collates table data in which the peak value of the absorbance at a predetermined reference pressure stored in advance corresponds to the concentration of the gas, and the peak value of the absorbance.

[0010] Further, in the gas measurement device according to one aspect of the present invention, the gas concentration calculation unit includes a peak value normalization unit that converts the peak value of the absorbance at a specific wavelength analyzed by the absorbance data analysis unit from the pressure in the reaction vessel calculated by the pressure calculation unit to a peak value at a predetermined reference pressure and normalizes it, and the data collation unit collates the table data in which the peak value of the absorbance at the reference pressure stored in advance corresponds to the concentration of the gas, and the normalized peak value of the absorbance.

[0011] Further, in the gas measurement device according to one aspect of the present invention, the peak detection unit may detect peak values of two adjacent points from the spectrum of the absorbance analyzed by the absorbance data analysis unit.

[0012] Further, in the gas measurement device according to one aspect of the present invention, when the peak detection unit detects a plurality of sets of peak values of two adjacent points within a predetermined wavelength range, the peak detection unit may select the set with the largest difference between the peak values of the two adjacent points.

[0013] A gas measurement method according to one aspect of the present invention includes an absorbance measurement step of irradiating detection light into a reaction vessel that generates a gas and measuring the absorbance of the detection light that has passed through the gas atmosphere in the reaction vessel, an absorbance data analysis step of spectrally analyzing the absorbance data measured in the absorbance measurement step, a peak detection step of detecting a plurality of peak values from the spectrum of the absorbance analyzed in the absorbance data analysis step, and a pressure calculation step of calculating the pressure in the reaction vessel based on the intensity ratio of two peak values among the plurality of peak values detected in the peak detection step.

Advantages of the Invention

[0014] According to one aspect of the present invention, a specific gas can be measured without providing a pressure sensor in a reaction vessel where the pressure changes.

Brief Description of Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Mode for Carrying Out the Invention

[0016] Hereinafter, a gas measurement device and a gas measurement method according to an embodiment of the present invention will be described in detail with reference to the drawings. First, an overview of the embodiment of the present invention will be described, and then details of the embodiment of the present invention will be described.

[0017] 〔Overview〕 In the gas concentration measurement device of Patent Document 1, the laser light emitted from the semiconductor laser is branched by an optical splitter and transmitted to the reference gas cell and the measurement gas cell. The light transmitted through the reference gas cell is received by a detector, and the received signal reaches the bipolar constant current power supply via a lock-in amplifier and an integrator. Then, a positive or negative current is passed from this bipolar constant current power supply to the Peltier element to control the temperature of the semiconductor laser and stabilize the emission of the laser light. The light transmitted through the measurement gas cell is received by a photodetector, and the received signal is sent to a lock-in amplifier and a lock-in amplifier. Then, the pressure is obtained by signal processing in a divider and a signal processing unit, and the gas concentration is obtained.

[0018] Thus, in the conventional gas concentration measuring device, it was necessary to install a cell for the measurement gas. Further, in this gas concentration measuring device, in order to control the output of the semiconductor laser, it was necessary to separately install a reference gas and a gas cell for enclosing the reference gas.

[0019] In an embodiment of the present invention, in a gas measuring device and a gas measuring method, detection light is irradiated into a reaction vessel that generates gas, and the absorbance of the detection light that has passed through the gas atmosphere in the reaction vessel is measured. Next, spectral analysis is performed on the measured absorbance data, and two peak values are detected from the spectrum of the analyzed absorbance. Then, the pressure in the reaction vessel is calculated based on the intensity ratio of the two detected peak values. As a result, since the pressure can be estimated from the peak value of the absorbance, it is not necessary to install a pressure sensor. In addition, it is not necessary to remove the pressure sensor associated with the heat treatment for sterilization or the like inside the reaction vessel. Further, since it is not necessary to extract gas such as in a gas chromatograph, it is possible to prevent impurities from entering the reaction vessel. Furthermore, it is possible to accurately estimate a specific gas concentration in a reaction vessel where the pressure changes.

[0020] 〔Embodiment〕 FIG. 1 is a configuration diagram of a methane generation device 1 according to an embodiment. As shown in FIG. 1, the methane generation device 1 includes a reaction vessel 2, a gas supply device 3, a generated gas extraction device 4, and a gas measurement device 5.

[0021] The reaction vessel 2 cultivates methanogenic bacteria in the liquid of the culture solution 6. Examples of methanogenic bacteria include Methanobacterium alcaliphilum, Methanobacterium bryantii, Methanobacterium congolense, Methanobacterium defluvii, Methanobacterium espanolae, Methanobacterium formicicum, Methanobacterium ivanovii, Methanobacterium palustre, Methanobacterium thermaggregans, Methanobacterium uliginosum, Methanobrevibacter acididurans, Methanobrevibacter arboriphilicus, Methanobrevibacter gottschalkii, Methanobrevibacter olleyae, Methanobrevibacter ruminantium, Methanobrevibacter smithii, Methanobrevibacter woesei, Methanobrevibacter wolinii, Methanothermobacter marburgensis, Methanothermobacter thermoautotrophicusThermoautotrophicus, Methanobacterium thermoautotrophicus, Methanothermobacter thermoflexus, Methanothermobacter thermophilics, Methanothermobacter wolfeii, Methanothermus sociabilis, Methanocorpusculum bavaricum, Methanocorpusculum parvum, Methanoculleus chikuoensis, Methanoculleus submarinus, Methanogenium frigidum, Methanogenium liminatans, Methanogenium marinum, Methanomicrobium mobile, Methanocaldococcus jannaschii, Methanococcus aeolicus, Methanococcus maripaludis, Methanococcus vannielii, Methanococcus voltaei, Methanothermococcus thermolithotrophicus, etc. can be exemplified.

[0022] The reaction vessel 2 of this embodiment cultures strains such as Methanobacteriales, Methanomicrobiales, Methanocellales, and Methanomassillicoccales as methane-producing bacteria. These hydrogenotrophic methane-producing bacteria may also be contained in anaerobic groundwater, and methane can be obtained by adding a mixed gas of carbon dioxide (CO 2 ) and hydrogen gas (H 2 ) to the anaerobic groundwater containing methane-producing bacteria. That is, the reaction vessel 2 stores a culture solution 6 (for example, anaerobic groundwater) containing a medium for culturing methane-producing bacteria. The inside of the reaction vessel 2 is in an anaerobic state with the oxygen content reduced as much as possible.

[0023] The gas supply device 3 opens the valve 3a and supplies carbon dioxide and hydrogen gas required by the methane-producing bacteria to the reaction vessel 2. The gas supply device supplies an H 2 / CO 2 mixed gas (for example, 80 vol.%: 20 vol.% by volume ratio) into the gas phase part in the reaction vessel 2, pressurizes it to a predetermined pressure, and starts culturing methane-producing bacteria.

[0024] The generated gas extraction device 4 opens the valve 4a based on the measurement result of the gas measurement device 5 and extracts methane generated by methane-producing bacteria (for example, hydrogenotrophic methane-producing bacteria). The generated gas extraction device 4 takes out the generated gas from the gas phase part in the reaction vessel 2 and stores it in an external tank (not shown). After the extraction of methane is completed, the valve 4a is closed, and again, an H 2 / CO 2 mixed gas is supplied from the gas supply device 3 to the reaction vessel 2 to culture methane-producing bacteria and produce methane.

[0025] Before starting the culture of methane-producing bacteria (H 2 / CO 2Before supplying the mixed gas to the reaction vessel 2, it is advisable to supply an inert gas into the reaction vessel 2 from the gas supply device 3 or the like. By supplying the inert gas (gas purge), the inside of the reaction vessel 2 can be made anaerobic. Examples of the inert gas include nitrogen gas, argon gas, and helium gas.

[0026] The reaction vessel 2 contains a culture solution 6 and H 2 / CO 2 A stirring mechanism 8 for stirring and mixing the area of the gas-liquid interface 7 between the culture solution 6 and the mixed gas (reaction gas) is provided. The stirring mechanism 8 includes stirring blades and agitates the gas-liquid interface 7 of the culture solution 6. Thereby, the dissolution of the reaction gas into the culture solution 6 is promoted. Note that if the area of the gas-liquid interface 7 can be increased, for example, a mechanism for vibrating the reaction vessel 2 itself may be used.

[0027] The gas measurement device 5 measures and outputs the concentration of methane gas generated in the reaction vessel 2. The measurement result of the gas measurement device 5 is managed by a peripheral device of the reaction vessel 2 (not shown), enabling long-term operation of the methane generation device 1 (long-term generation of methane). The gas measurement device 5 includes an absorbance measurement device 10, an information processing unit 11, and a concentration output unit 12.

[0028] The absorbance measurement device 10 irradiates detection light into the reaction vessel 2 that generates methane gas, and measures the absorbance of the detection light that has passed through the gas phase portion containing gas in the reaction vessel 2, that is, the gas atmosphere in the reaction vessel 2 (absorbance measurement step). In this embodiment, the measurement target is methane gas, and it is preferable to use at least one of infrared rays and near-infrared rays as the detection light. Note that the measurement target is not limited to methane gas. When inspecting a specific gas other than methane gas, detection light with a wavelength suitable for that specific gas may be used.

[0029] The absorbance measuring device 10 can adopt, for example, a probe type inserted into the reaction vessel 2. The probe type absorbance measuring device 10 includes a light projecting part and a light receiving part for detection light on the proximal end side of the probe, and a reflecting part for reflecting the detection light to the proximal end side at the tip of the probe. A vent hole is provided between the proximal end and the tip of the probe, and the detection light can be irradiated onto the gas in the reaction vessel 2 passing through this vent hole, and its absorbance can be measured.

[0030] The information processing unit 11 includes a device control unit 20, an absorbance data analysis unit 21, a peak detection unit 22, a pressure calculation unit 23, and a gas concentration calculation unit 24 (peak value normalization unit 24a and data collation unit 24b). Although these are separated as functions, they may be configured by the same device (for example, an arithmetic processing device such as a PC) as a physical entity (hardware), or may be configured by a plurality of devices.

[0031] The absorbance data analysis unit 21, the peak detection unit 22, the pressure calculation unit 23, and the gas concentration calculation unit 24 process the measurement data of the absorbance measuring device 10. The device control unit 20 controls the operation of the absorbance measuring device 10 and, based on the processing result of the measurement data of the absorbance measuring device 10, controls the operation of the valve 3a of the gas supply device 3, the valve 4a of the generated gas extraction device 4, and other peripheral devices of the reaction vessel 2 (not shown). During the progress of the reaction, it is preferable to close the valves 3a and 4a so that the inside of the reaction vessel 2 is in a sealed state.

[0032] The absorbance data analysis unit 21 performs spectral analysis on the absorbance data measured by the absorbance measuring device 10 (absorbance data analysis step). FIG. 2 is a graph showing an example of the absorption spectrum of methane gas according to an embodiment. As shown in FIG. 2, the absorption spectrum of methane gas shows a plurality of characteristic peak values I1, I2, and I3 in the wavelength range from infrared to near-infrared.

[0033] The peak detection unit 22 detects two peak values from the absorbance spectrum analyzed by the absorbance data analysis unit 21 (peak detection step). Specifically, the peak detection unit 22 detects two adjacent peak values including the highest peak value I1 from the absorbance spectrum analyzed by the absorbance data analysis unit 21. By detecting two adjacent peak values, the detection range of the absorbance spectrum can be narrowed, and the load of arithmetic processing can be reduced. Note that the peak value can be detected from where the slope of the absorbance changes from zero or from + to -.

[0034] As shown in FIG. 2, when a plurality of sets of two adjacent peak values (for example, the set of I1 and I2, the set of I1 and I3) are detected within a predetermined wavelength range, the peak detection unit 22 selects the set (the set of I1 and I2) in which the difference between the two adjacent peak values is the largest. Thereby, the change in the intensity ratio (I1 / I2) of the peak values described later becomes prominent, and the subsequent pressure estimation accuracy is improved. If the specific wavelength at which characteristic peak values appear in advance is known, the set of two peak values may be determined as the set of that specific wavelength.

[0035] The pressure calculation unit 23 calculates the pressure in the reaction vessel 2 based on the intensity ratio (I1 / I2) of the two peak values detected by the peak detection unit 22 (pressure calculation step). FIG. 3 is a graph showing the relationship between the intensity ratio (I1 / I2) of two peak values and the pressure according to an embodiment. As shown in FIG. 3, there is a correlation between the intensity ratio (I1 / I2) of two peak values and the pressure. The pressure calculation unit 23 calculates the pressure at the time of spectrum acquisition based on the relationship between the intensity ratio (I1 / I2) of two peak values and the pressure shown in FIG. 3.

[0036] The gas concentration calculation unit 24 calculates the concentration of the gas based on the peak value of the absorbance at a specific wavelength (I2 in this embodiment) analyzed by the absorbance data analysis unit 21 and the pressure in the reaction vessel 2 calculated by the pressure calculation unit 23 (gas concentration calculation step). Note that the peak value of the absorbance at the specific wavelength may be I1, but since there is another peak value I3 nearby, it may be affected. Therefore, the gas concentration calculation unit 24 refers to I2.

[0037] The gas concentration calculation unit 24 includes a peak value normalization unit 24a that converts and normalizes the peak value of the absorbance at a specific wavelength (I2 in this embodiment) analyzed by the absorbance data analysis unit 21 to the peak value at a predetermined reference pressure from the pressure in the reaction vessel 2 calculated by the pressure calculation unit 23, and a data collation unit 24b that collates the table data in which the peak value of the absorbance at the reference pressure stored in advance corresponds to the gas concentration, and the normalized peak value of the absorbance.

[0038] Figure 4 is a graph showing the relationship between the methane concentration and the absorbance at each pressure according to an embodiment. As shown in Figure 4, the methane concentration and the absorbance show linearity with different slopes depending on the pressure. That is, when the methane concentration is constant, the absorbance and the pressure at each pressure are in a certain ratio. Therefore, the peak value normalization unit 24a can normalize the absorbance to the absorbance at the reference pressure (here, 1 atm), and convert the absorbance (I2 in this embodiment) to the peak value at 1 atm. Then, the data collation unit 24b is provided with table data storing the relationship between the calibration curve of the methane concentration and the absorbance at 1 atm, and calculates the methane concentration from the absorbance converted to 1 atm obtained by the peak value normalization unit 24a.

[0039] The concentration output unit 12 outputs the concentration of the methane gas calculated by the gas concentration calculation unit 24 (gas concentration output step). The concentration output unit 12 is, for example, a display device or the like. Note that the concentration output unit 12 may output not only the concentration of the methane gas but also the pressure in the reaction vessel 2 obtained during the calculation thereof.

[0040] Thus, according to the gas measurement device 5 according to the above-described embodiment, the pressure inside the reaction vessel 2 can be estimated by comparing the intensity ratio of the peak values of two adjacent absorbances in the absorbance spectrum. Thereby, the pressure inside the reaction vessel 2 can be estimated without using a pressure sensor. Further, there is no need to separately install a reference gas and a gas cell for enclosing the reference gas, and the pressure inside the reaction vessel 2 can be estimated only from the acquired spectrum data. Further, since the absorbance having pressure dependence can be corrected by the estimated pressure, gas concentration comparison under the same pressure conditions can be performed.

[0041] As described above, the gas measurement device 5 according to the present embodiment includes an absorbance measurement device 10 that irradiates detection light into the reaction vessel 2 that generates methane gas and measures the absorbance of the detection light that has passed through the gas atmosphere inside the reaction vessel 2, an absorbance data analysis unit 21 that performs spectral analysis on the absorbance data measured by the absorbance measurement device 10, a peak detection unit 22 that detects two peak values I1 and I2 from the absorbance spectrum analyzed by the absorbance data analysis unit 21, and a pressure calculation unit 23 that calculates the pressure inside the reaction vessel 2 based on the intensity ratio (I1 / I2) of the two peak values detected by the peak detection unit 22.

[0042] According to this configuration, a specific gas can be measured inside the reaction vessel 2 where the pressure changes without providing a pressure sensor. That is, since the pressure can be estimated from the peak value of the absorbance, the installation of a pressure sensor becomes unnecessary. Further, it is not necessary to remove the pressure sensor associated with heat treatment for sterilization or the like inside the reaction vessel 2. Further, since it is not necessary to extract a gas sample such as a gas chromatograph, contamination of impurities into the reaction vessel can be prevented. Furthermore, the specific gas concentration inside the reaction vessel where the pressure changes can be accurately estimated.

[0043] In addition, the gas measurement method according to the present embodiment includes an absorbance measurement step of irradiating detection light into a reaction vessel 2 that generates gas and measuring the absorbance of the detection light that has passed through the gas atmosphere in the reaction vessel 2, an absorbance data analysis step of performing spectral analysis on the absorbance data measured in the absorbance measurement step, a peak detection step of detecting two peak values I1 and I2 from the spectrum of the absorbance analyzed in the absorbance data analysis step, and a pressure calculation step of calculating the pressure in the reaction vessel 2 based on the intensity ratio (I1 / I2) of the two peak values detected in the peak detection step.

[0044] According to this configuration, similarly, in the reaction vessel 2 where the pressure changes, a specific gas can be measured without providing a pressure sensor.

[0045] As described above, the preferred embodiments of the present invention have been described with reference to the drawings. However, the present invention is not limited to the above embodiments. The various shapes and combinations of the constituent members shown in the above-described embodiments are merely examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

[0046] For example, the measurement target is not limited to methane gas. Similar to the above-described methane gas, hydrocarbons, nitrogen compounds, and sulfur compounds that exhibit near-infrared and infrared absorption can also be measurement targets. Note that if the relationship between the peak intensity ratio (I1 / I2) and the pressure and the relationship between the gas concentration and the absorbance at each pressure are known, pressure correction can be performed without using a pressure sensor, and the concentration of the gas can be quantitatively evaluated. Therefore, the measurement target is not limited to gases that exhibit near-infrared and infrared absorption.

[0047] Further, for example, the peak detection unit 22 is not limited to a configuration that detects only two peak values. For example, the peak detection unit 22 may first detect three or more peak values, select the optimal two of them, and use those peak values. Furthermore, the peak detection unit 22 may correct the pressure and gas concentration using one or more peak values that have leaked from the selection.

[0048] Note that some or all of the above-described embodiments may be described as follows in the appended claims, but are not limited thereto.

[0049] (Appendix 1) An absorbance measurement device that irradiates detection light into a reaction vessel that generates gas and measures the absorbance of the detection light that has passed through the gas atmosphere in the reaction vessel, An absorbance data analysis unit that performs spectral analysis on the absorbance data measured by the absorbance measurement device, A peak detection unit that detects a plurality of peak values from the spectrum of the absorbance analyzed by the absorbance data analysis unit, A gas concentration output unit that outputs the concentration of the gas in the reaction vessel based on the intensity ratio of two peak values among the plurality of peak values detected by the peak detection unit. A gas measurement device comprising:

Explanation of Signs

[0050] 1... Methane generation device, 2... Reaction vessel, 3... Gas supply device, 3a... Valve, 4... Generated gas extraction device, 4a... Valve, 5... Gas measurement device, 6... Culture solution, 7... Gas-liquid interface, 8... Stirring mechanism, 10... Absorbance measurement device, 11... Information processing unit, 12... Concentration output unit, 20... Device control unit, 21... Absorbance data analysis unit, 22... Peak detection unit, 23... Pressure calculation unit, 24... Gas concentration calculation unit, 24a... Peak value normalization unit, 24b... Data matching unit, CO 2 ... Carbon dioxide, H 2 ... Hydrogen gas, I1... Peak value, I2... Peak value, I3... Peak value

Claims

1. An absorbance measurement device that irradiates detection light into a reaction vessel that generates gas and measures the absorbance of the detection light that has passed through the gas atmosphere in the reaction vessel; An absorbance data analysis unit that spectrally analyzes the absorbance data measured by the absorbance measurement device; A peak detection unit that detects a plurality of peak values from the spectrum of the absorbance analyzed by the absorbance data analysis unit; A gas measurement device comprising: a pressure calculation unit that calculates the pressure in the reaction vessel based on the intensity ratio of two peak values among the plurality of peak values detected by the peak detection unit.

2. The gas measurement device according to claim 1, further comprising a gas concentration calculation unit that calculates the concentration of the gas based on the peak value of the absorbance at a specific wavelength analyzed by the absorbance data analysis unit and the pressure in the reaction vessel calculated by the pressure calculation unit.

3. The gas measurement device according to claim 2, further comprising a gas concentration output unit that outputs the concentration of the gas calculated by the gas concentration calculation unit.

4. The gas measurement device according to claim 2, wherein the gas concentration calculation unit includes a data collation unit that collates table data in which the peak value of the absorbance at a predetermined reference pressure corresponds to the concentration of the gas, and the peak value of the absorbance.

5. The gas concentration calculation unit includes a peak value normalization unit that converts and normalizes the peak value of the absorbance at a specific wavelength analyzed by the absorbance data analysis unit from the pressure in the reaction vessel calculated by the pressure calculation unit to a peak value at a predetermined reference pressure, The gas measurement device according to claim 4, wherein the data collation unit collates the table data in which the peak value of the absorbance at the reference pressure stored in advance corresponds to the concentration of the gas, and the normalized peak value of the absorbance.

6. The gas measurement device according to any one of claims 1 to 5, wherein the peak detection unit detects two adjacent peak values from the spectrum of the absorbance analyzed by the absorbance data analysis unit.

7. The gas measurement device according to claim 6, wherein when the peak detection unit detects a plurality of sets of two adjacent peak values within a predetermined wavelength range, the peak detection unit selects the set having the largest difference between the two adjacent peak values.

8. An absorbance measurement step of irradiating detection light into a reaction vessel that generates gas and measuring the absorbance of the detection light that has passed through the gas atmosphere in the reaction vessel; An absorbance data analysis step of performing spectral analysis on the absorbance data measured in the absorbance measurement step; A peak detection step of detecting a plurality of peak values from the spectrum of the absorbance analyzed in the absorbance data analysis step; A gas measurement method, comprising a pressure calculation step of calculating the pressure in the reaction vessel based on the intensity ratio of two peak values among the plurality of peak values detected in the peak detection step.

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