JP4210502B2 - Batch type multi-component analyzer and method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a batch type multi-component analysis apparatus and method for separately analyzing multi-component concentrations contained in a sample gas by the NDIR method.
[0002]
[Prior art]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-201901 [Patent Document 2]
One of the gas analyzers is a non-dispersive infrared gas analyzer (NDIR) using infrared absorption. This non-dispersive infrared gas analyzer is simple and robust in structure, and can analyze multiple components at the same time with high selectivity and is capable of continuous measurement. Widely used.
[0003]
In the gas analyzing apparatus based on the NDIR method, zero calibration and span calibration are generally performed in order to correct a drift that causes an error. Zero calibration is performed more frequently than span calibration using a calibration gas with a known concentration of the measured component because it uses a gas that does not contain the gas component to be measured (usually clean air or nitrogen gas). The This zero calibration is particularly effective because it can easily perform corrections such as a temperature drift with a large daily variation. Therefore, conventionally, zero calibration is performed before measuring the sample gas, and then the sample gas is measured. This is because the measurement is continuous and it is necessary to continuously display correct measurement values after calibration.
[0004]
However, as described above, when zero calibration is performed before measuring the sample gas and then the sample gas is measured, after the measurement, the sample gas remains in the gas flow path such as a measurement cell. When the power is turned off, dirt remains attached or remains in the flow path, which causes deterioration of the apparatus. In order to avoid this, it is necessary to purge with zero gas.
[0005]
On the other hand, for example, as described in Patent Document 1, a specific measurement target component in the sample gas is detected, and automatic zero calibration is performed every predetermined time in the measurement mode. When the infrared gas analyzer is in the measurement mode, it is determined whether or not the measurement is completed depending on whether or not the concentration of the measurement target component is equal to or lower than a predetermined value. Although it is conceivable to perform zero calibration automatically, in the method of Patent Document 1, sample gas measurement and zero calibration are not necessarily performed in pairs. Purge must be done before turning off.
[0006]
By the way, conventionally, chlorofluorocarbon gas is generally used as a refrigerant used in a refrigerator such as a refrigerator or a cooler. In addition to CFC and HCFC, which are old refrigerants, there are HFCs that are new refrigerants. However, there is a problem of ozone layer destruction and global warming, and it is obliged to collect and recycle Freon gas. Moreover, it is required to reliably destroy chlorofluorocarbons that cannot be recycled.
[0007]
On the other hand, as new refrigerants, there are typical Freon 410A, Freon 407C, Freon 404A, and Freon 507A, which include a plurality of single-component Freon gases [Flon 32 (R32), Freon 125 (R125), Freon 134a (R134a). , Freon 143a (R143a)] is a so-called mixed refrigerant in which several kinds of CFCs are mixed at a predetermined ratio.
[0008]
Therefore, if different types of chlorofluorocarbon gases (such as chlorofluorocarbon 12 (R12) and chlorofluorocarbon 22 (R22)) with different component ratios are mixed due to erroneous recovery or the like, recycling becomes impossible. For this reason, it is required to measure the component ratio of Freon gas. As a means for measuring the freon gas concentration, for example, as described in Patent Document 2, there is one based on the NDIR method, which is suitable for ratio analysis of various refrigerant components contained in the mixed refrigerant. Can be used.
[0009]
[Problems to be solved by the invention]
In particular, when the sample gas is a mixed refrigerant and the ratio of each refrigerant component contained in the mixed refrigerant is measured, the so-called batch type gas in which the measurement is performed in a single shot. In the analyzer, when an apparatus such as that described in Patent Document 1 is adopted, the operation procedure of the apparatus becomes complicated, and it is necessary to operate the pump each time zero gas is supplied for purging. As a result, the pump is consumed significantly.
[0010]
The present invention has been made in consideration of the above-described matters. The purpose of the present invention is to simplify the measurement operation when analyzing the concentration of multiple components contained in a sample gas by the NDIR method, and to provide a pump for purging. It is an object of the present invention to provide a batch type multi-component analysis apparatus and method that can reduce the number of operations such as the above.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention, a batch-type multi-component configured to measure the concentration of a multi-component contained in a sample gas by the NDIR method and complete the measurement work by obtaining a measurement result. the analysis device, immediately after the measurement of the sample gas, the zero gas free of the measurement target component in the gas analyzer unit performs Pado and data sampling is supplied by the operation of the pump, and configured to perform zero calibration, the immediately preceding It is configured to obtain a measurement result by performing a concentration calculation based on a measurement signal from the gas analysis unit obtained at the time of sample gas measurement and a zero signal from the gas analysis unit obtained at the time of zero calibration. A batch type multi-component analyzer is provided (claim 1).
[0012]
Further, in the present invention, in the batch type multi-component analysis method for measuring the concentration of multi-components contained in the sample gas by the NDIR method and completing the measurement work by obtaining the measurement result , immediately after measuring the sample gas , Zero gas that does not contain the measurement target component is supplied to the gas analyzer by operating the pump, purge and data sampling are performed, zero calibration is performed, and measurement from the gas analyzer obtained during the previous sample gas measurement A batch type multi-component analysis method is provided, wherein a concentration calculation is performed based on a signal and a zero signal from the gas analysis unit obtained at the time of the zero calibration to obtain a measurement result (claim 2).
[0013]
In the multi-component analysis apparatus and method having the above-described configuration, it is not particularly necessary to perform a purge after the measurement work is completed, and the work can be completed by immediately turning off the power of the apparatus. In addition, since zero calibration and purging are simultaneously performed immediately after measurement of the sample gas, it is not necessary to operate a special pump for purging, and a longer life of sampling members such as a pump can be expected.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the details of the present invention will be described with reference to the drawings. 1 to 3 show one embodiment of the present invention. In this embodiment, as an example of a multi-component analyzer, a mixed refrigerant measuring device in which a sample gas is a mixed refrigerant and a measurement target component is a refrigerant component constituting the mixed refrigerant is illustrated. First, FIG. 1 schematically shows a configuration example of the mixed refrigerant measuring apparatus. In this figure, 1 is a cylinder containing a mixed refrigerant as the sample gas S, and 2 is a cylinder valve. Reference numeral 3 denotes a sample gas supply path that connects between the cylinder 1 and a mixed refrigerant measuring device 5 described later, and includes a pressure regulator 4.
[0015]
Reference numeral 5 denotes a mixed refrigerant analyzer, which is configured as follows, for example. First, 6 and 7 are gas inlets and gas outlets formed in the mixed refrigerant analyzer 5, and the gas inlet 6 is connected to the downstream end of the sample gas supply path 3. Reference numeral 8 denotes a gas flow path formed between the gas inlet 6 and the gas outlet 7, and the sample gas S from the gas inlet 6 flows therethrough. A three-way solenoid valve 11 and gas analyzers 12 and 13 are provided in this order. The three-way solenoid valve 11 is connected to the gas flow path 8 so that the first port 11a that is closed when the power is off is connected to the oil filter 10 and the second port 11b that is always open is connected to the gas analyzer 12. It is intervened. Reference numeral 14 denotes a gas discharge passage connected to the gas outlet 7, and the downstream side thereof is connected to an appropriate gas recovery section (not shown).
[0016]
The gas analyzers 12 and 13 are multi-component analyzers that analyze the ratio of each refrigerant component contained in the mixed refrigerant by the NDIR method, and are configured as shown in FIG. 2, for example. That is, one gas analysis unit 12 includes a cell 12a, an infrared light source 12b and an optical chopper 12c provided on one window 12a1 side of the cell 12a, and a detection unit 12d provided on the other window 12a2 side of the cell 12a. The other gas analyzer 13 includes a cell 13a, an infrared light source 13b and an optical chopper 13c provided on one window 13a1 side of the cell 13a, and a detection provided on the other window 13a2 side of the cell 13a. Part 13d.
[0017]
The cell 12a of the one gas analysis unit 12 and the cell 13a of the other gas analysis unit 13 are connected in series, and the sample gas S that has passed through the three-way solenoid valve 11 is connected to one cell 12a located on the upstream side. Is supplied, and the sample gas S that has passed through the cell 12a is supplied to the other cell 13a connected in series so as to be positioned downstream of the cell 12a.
[0018]
In addition, the detection units 12d and 13d can detect, for example, seven (seven types) refrigerant components included in the mixed refrigerant as the sample gas S by the two detection units 12d and 13d. The detection unit 12d is provided with four pyroelectric detectors and four bandpass filters corresponding to four refrigerant components of the seven refrigerant components, and the other detection unit 13d Are provided such that three pyroelectric detectors and three band-pass filters form a pair corresponding to the remaining three refrigerant components of the seven. In this case, the seven band pass filters are set so that the center wavelength to be transmitted falls within a predetermined range in accordance with the infrared absorption spectra of the seven refrigerant components.
[0019]
In FIG. 1 again, reference numeral 15 denotes a zero gas inlet formed in the mixed refrigerant analyzer 5. A zero gas supply path 16 is provided between the zero gas inlet 15 and the third port 11c that is open when the three-way solenoid valve 11 is turned off. Is formed. The zero gas supply path 16 is provided with a filter 17 and a suction pump 18 in this order. The zero gas supply path 16 supplies the zero gas Z to the cells 12a and 13a of the gas analyzers 12 and 13 having the above-described configuration via the three-way solenoid valve 11. In this embodiment, the zero gas inlet Air is introduced from 15, and this air becomes clean air through the filter 17, and is configured to become zero gas Z.
[0020]
Although not shown, the mixed refrigerant measuring device 5 includes a plurality of (seven in this example) refrigerant components based on, for example, sequence control of the respective units, or based on the outputs of the gas analyzing units 12 and 13. An arithmetic control device (for example, a personal computer) that performs density calculation (component ratio calculation) is provided.
[0021]
The operation of measuring the mixed refrigerant using the mixed refrigerant measuring device 5 having the above configuration will be described with reference to FIG. FIG. 3 shows the on-off state of each part of the mixed refrigerant measuring device 5 and the display contents on the screen of a display device (for example, a liquid crystal display device) attached to the arithmetic and control device over time.
[0022]
Before the measurement, “Ready To Measurement” is displayed on the display screen of the display device attached to the arithmetic and control unit (see g in FIG. 3). Before the measurement, the cylinder valve 2 is closed (see a in FIG. 3), the three-way solenoid valve 11 is off (see c in FIG. 3), and the suction pump 18 is also off (d in FIG. 3). reference).
[0023]
In this state, when the measurement key of the arithmetic control device is manually turned on (see b in FIG. 3), the three-way solenoid valve 11 is turned on (see c in FIG. 3). When the cylinder valve 2 is manually opened in this state (see a in FIG. 3), the mixed refrigerant in the cylinder 1 flows into the sample gas supply path 3 as the sample gas S, the pressure is adjusted, and the mixed refrigerant passes through the gas inlet 6. It enters the gas flow path 8 in the measuring device 5. The sample gas S sampled enters the cell 12a of the upstream gas analyzer 12 through the open / close valve 9, the oil filter 10, and the three-way solenoid valve 11, and the sample gas S that has passed through the cell 12a flows downstream. It enters the cell 13a of the gas analyzer 13. In these gas analyzers 12 and 13, the sample gas S is analyzed while the sample gas S is being supplied to the cells 12a and 13a. By this sample gas analysis, the sensor signal rises (see e in FIG. 3), and thereafter, sampling of data is performed in the respective gas analyzers 12 and 13 (see f in FIG. 3). As a result, a measurement signal s for each component is obtained from each gas analysis unit 12, 13. Then, the sample gas S exiting the downstream gas analyzer 13 enters the gas discharge channel 14 from the gas outlet 7 and is then recovered. The three-way solenoid valve 11 is turned on after being turned on for a predetermined time (see c in FIG. 3), and the cylinder valve 3 is closed for a while after the three-way solenoid valve 11 is turned off (see a in FIG. 3).
[0024]
When the suction pump 18 is turned on (see d in FIG. 3), the zero gas Z from the zero gas supply path 16 enters the cell 12a of the upstream gas analyzer 12 through the three-way solenoid valve 11, and passes through the cell 12a. The zero gas Z enters the cell 13a of the gas analysis unit 13 on the downstream side, and the rising sensor signal falls (see e in FIG. 3). In the gas analyzers 12 and 13, the zero gas Z is the cell 12a. While being supplied to 13a, zero calibration with zero gas Z is performed. As a result, a zero signal z for each component is obtained from each gas analyzer 12, 13. Then, the zero gas Z that has flowed sequentially through the gas analyzers 12 and 13 enters the gas discharge channel 14 from the gas outlet 7 and is then recovered.
[0025]
In the arithmetic and control unit, the measurement signals s (s1 to s7) output from the plurality of pyroelectric detectors provided so as to correspond to the plurality of components obtained at the time of measuring the sample gas and zero calibration are obtained. A plurality of refrigerants contained in the sample gas S, for example, by taking a ratio [log (s / z)] based on the zero signals z (z1 to z7) from the pyroelectric detectors obtained at times. The component ratio is determined.
[0026]
As described above, in the mixed refrigerant measuring apparatus and method of the present invention, the cylinder 1 containing the mixed refrigerant to be measured and the mixed refrigerant measuring apparatus 5 are connected by the sample gas supply path 3, and the measurement key is operated. After that, it is only necessary to open and close the cylinder 1 and to wait for the measurement result thereafter. After obtaining the measurement result, it is not necessary to perform purging. That is, in the mixed refrigerant measuring apparatus and method of the present invention, sample gas measurement is first performed, and immediately after that, zero calibration is performed, and sample gas measurement and zero calibration are performed in pairs. If the refrigeration oil in the recovered refrigerant is mixed in the sample gas S and the refrigeration oil is completely attached to the cells 12a, 13a, etc., zero calibration is performed immediately after the sample gas measurement. Thus, the inside of the cells 12a, 13a, etc. is purged with the zero gas Z. Therefore, impurities contained in the sample gas S can be effectively removed, and it is not necessary to flow a purge gas, and the operation can be completed by turning off the power immediately after zero calibration.
[0027]
As described above, zero calibration and purging are simultaneously performed immediately after the measurement of the sample gas. Therefore, it is not necessary to operate the pump 18 for purging, and the life of members around the gas sampling can be expected to be extended.
[0028]
In the above-described embodiment, the rise of the sensor signal accompanying the sampling of the sample gas S is detected, and a predetermined time is applied to data sampling after the rise is detected. Data sampling that is not affected by operation delay is possible.
[0029]
In the above-described embodiment, a mixed refrigerant is illustrated as the sample gas S, and a mixed refrigerant measuring device is illustrated as the multicomponent analyzer, but it goes without saying that the present invention is not limited to this. Absent.
[0030]
【The invention's effect】
As described above, in the present invention, in the batch type multi-component analyzer and method for measuring the concentration of multi-components contained in a sample gas by the NDIR method and completing the measurement work by obtaining the measurement result . Immediately after measuring the sample gas, zero gas that does not contain the component to be measured is supplied to the gas analyzer by operating the pump and purge and data sampling are performed to perform zero calibration. As a result, the measurement procedure is simplified, the operation of the pump for purging is reduced as much as possible, and the sample gas is like a mixed refrigerant. You can also perform stable measurement over time.
[Brief description of the drawings]
FIG. 1 is a diagram schematically showing an example of the configuration of a batch type multi-component analyzer after the present invention.
FIG. 2 is a diagram schematically showing an example of a configuration of a gas analysis unit of the batch type multi-component analyzer.
FIG. 3 is a diagram showing an example of a measurement sequence in the batch type multi-component analyzer.
[Explanation of symbols]
5 ... Multi-component analyzer, 12, 13 ... Gas analyzer, S ... Sample gas, Z ... Zero gas .

Claims (2)

In the batch type multi-component analyzer configured to complete the measurement work by measuring the concentration of the multi-component contained in the sample gas by the NDIR method and obtaining the measurement result , immediately after measuring the sample gas , the zero gas free of the measurement target component in the gas analyzer unit performs purging and data sampling is supplied by the operation of the pump, and configured to perform zero calibration, the gas analyzer unit obtained at the time of the sample gas measurement of the immediately preceding A batch type multi-component analyzer configured to obtain a measurement result by performing a concentration calculation based on the measurement signal and the zero signal from the gas analyzer obtained during the zero calibration. In batch type multi-component analysis method that completes the measurement work by measuring the concentration of multi-components contained in sample gas by NDIR method and obtaining the measurement result, it is measured in gas analyzer immediately after measurement of sample gas Zero gas that does not contain the target component is supplied by operating the pump, and purge and data sampling are performed to perform zero calibration, and the measurement signal from the gas analyzer obtained during the previous sample gas measurement and the zero calibration A batch type multi-component analysis method characterized in that a concentration calculation is performed based on a zero signal from the gas analyzer obtained at times to obtain a measurement result.

Images