JPH0829346A - Gas analyser - Google Patents

Abstract

PURPOSE:To provide a gas analyser simple in constitution and capable of meas uring many components with high accuracy. CONSTITUTION:A plurality of cells 7, 3 including such a case that cell lengths L1, L2 (>L1) are mutually different, communicate with each other through a communication part 21 to constitute a single gas route and a cut-on filter 100 as an infrared transmitting/reflecting means spectrally diffracting an infrared wavelength is provided on the side of a light source l. An NOx measuring cell 3 with a cell length L2 of 60mm, a CO2 measuring cell 7 with a cell length L2 of 1mm, a condenser microphone (NOx infrared detector) 5 and a pyroelectric detector (CO2 infrared detector) 9 allowed to communicate with each other by the communication part 21 are provided on the infrared transmission and reflection sides of the optical filter 100.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas analyzer, and in particular, a plurality of cells including those having different cell lengths are sequentially connected via a communication portion to form a single gas path, and two or more cells are formed. A new non-dispersive infrared gas analyzer (Non Dispersive Infrared Analyzer) that can detect measured components simultaneously with high accuracy.
yzer: hereinafter referred to as NDIR).

[0002]

2. Description of the Related Art The Lambert-Beer law is applied to the measurement of NDIR. According to the law shown in the following formula (1), if the cell length is constant, the larger the absorption coefficient of the component is, or the higher the concentration of the measured component is, the more the calibration curve is bent. . Further, if the concentration of the measurement component is constant, the longer the cell length, the larger the bending of the calibration curve. I = I ₀ · exp (−μ · c · L) (1) I ₀ : Incident light intensity c: Concentration of measurement component (amount of infrared rays absorbed in the cell) μ: Absorption coefficient peculiar to measurement component I: Transmitted light intensity
L: cell length

Therefore, in the NDIR analyzer, such a bend is linearized by an approximate expression.
There is a limit due to the accuracy of calculations. On the other hand, the longer the cell length L, the higher the sensitivity. Therefore, the cell length L is determined in consideration of the sensitivity and the bending. However, there is a troublesome problem that the compatible cell length L differs depending on the measurement component and its concentration. This problem is dealt with by the above-mentioned linearization, but if the correction cannot be completed, the cell length L must be changed.

For example, in a heavy oil boiler used in an electric power company, etc., due to NO _X regulation, which is one of the measurement components,
Although denitration measures to suppress a certain concentration or less in the NO _X components are taken, for example, the NO _X emission concentration of about 20-3
When suppressing the 0 ppm, it is required NO _X measuring range of 0 to 50 ppm. Although the CO ₂ concentration varies depending on the combustion state, it is about 14% when the boiler is operating, and normally a CO ₂ measurement range of 0 to 20% is required.

Therefore, a NO _X meter for measuring NO _X whose emission concentration is suppressed to about 20 to 30 ppm, and about 14%
The cell length is greatly different from that of a CO ₂ meter for measuring CO ₂ having a concentration of. For example, in a flue gas analyzer, the cell length is set to 60 mm for measuring NO _x and the emission concentration is about 20.
-30 ppm NO _x is measured, and the cell length is set to 1 mm for CO ₂ measurement, and the concentration of C is about 14%.
O ₂ is being measured.

[0006]

As described above, when the concentrations of the two components are different, the compatible cell lengths are different.
When the absorption intensity, the detection method, and the measured concentration of each measurement component differed greatly, a single cell could not handle it. In order to avoid this, conventionally, two components are measured on two benches, respectively. Therefore, each bench requires a single cell having a cell length L corresponding to the measured component. However, a plurality of measuring cells are required, and a plurality of gas introducing passages (gas passages) are also required, resulting in a complicated structure.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a gas analyzer having a simple structure and capable of performing multi-component measurement with high accuracy.

[0008]

The present invention comprises means for solving the above-mentioned problems as follows. That is, in the invention described in claim 1, for example, as shown in FIG. 1 (or FIG. 2), a plurality of measurement cells including cases where the cell lengths are different from each other are sequentially communicated through the communication section to form a single gas. In a gas analyzer having a path, an infrared transmitting / reflecting means 100 is provided adjacent to the light source 1, and the infrared transmitting / reflecting means 100 has the infrared transmitting side and the infrared reflecting side, respectively. It is characterized in that at least one set of measurement cells 3 and 7 communicated by the communication section 21 and infrared detectors 5 and 9 respectively corresponding to the measurement cells are provided.

According to the second aspect of the invention, for example, as shown in FIG. 3, a plurality of measurement cells, including the case where the cell lengths are different from each other, are sequentially connected through the communication section to form a single gas path. In the gas analyzer, the first infrared transmission / reflection means 100 is provided adjacent to the light source 1, and the infrared transmission side and the infrared reflection side of the first infrared transmission / reflection means 100 are provided. A first measurement cell 3 and a second measurement cell 7 which are respectively connected by the communication section 21 are provided, and the first measurement cell 3 and the first infrared detection corresponding to the first measurement cell 3 are provided. The second infrared transmitting / reflecting means 300 is provided between the second infrared transmitting / reflecting means 300 and the second infrared transmitting / reflecting means 300, and the third infrared detector 12 is provided on the infrared reflecting side of the second infrared transmitting / reflecting means 300. The second infrared detector 9 corresponding to the second measuring cell 7 is provided. It is a symptom.

In the invention described in claim 3, for example, as shown in FIG. 4, the infrared reflection side of the first infrared transmission / reflection means 300 in the invention described in claim 2 and the third infrared detector. The third measuring cell 23 is interposed between the first measuring cell 12 and the second measuring cell 12.

According to the fourth aspect of the present invention, for example, as shown in FIG. 5, a plurality of measuring cells including those having different cell lengths are sequentially connected through the connecting portion to form a single gas path. In the gas analyzer, the first infrared transmission / reflection means 100 is provided adjacent to the light source 1, and the second infrared transmission is provided on the infrared transmission side of the first infrared transmission / reflection means 100. A first measuring cell 3 and a first infrared detector corresponding to the first measuring cell 3 on the infrared transmitting side of the second infrared transmitting / reflecting means 300 while the reflecting means 300 is provided in series. 5, the first infrared transmitting / reflecting means 100 is provided.
The second measurement cell 7 and the second infrared detector 9 corresponding to the second measurement cell 7 are provided on the infrared reflection side of the infrared reflection side of the second infrared transmission / reflection means 300. Is provided with a third measuring cell 47 and a third infrared detector 12 corresponding to the third measuring cell 47.

In a fifth aspect of the present invention, for example, as shown in FIG. 6, a plurality of measurement cells including cases where the cell lengths are different from each other are sequentially connected through a communication section to form a single gas path. In the gas analyzer, the first measuring cell 3 is provided between the light source 1 and the first infrared transmitting / reflecting means 100, and the infrared transmitting of the first infrared transmitting / reflecting means 100 is performed. The second infrared transmitting / reflecting means 300 is provided on the side,
While the first infrared detector 5 is provided on the infrared transmission side of the second infrared transmission / reflection means 300, the second measurement is performed on the infrared reflection side of the first infrared transmission / reflection means 100. Cell 7 and its second measuring cell 7 and corresponding second infrared detector 9
And a third measurement cell 47 and a third infrared detector 12 corresponding to the third measurement cell 47 on the infrared reflection side of the second infrared transmission / reflection means 300. It is characterized by that.

According to the sixth aspect of the present invention, for example, as shown in FIG. 7, a plurality of measurement cells including the case where the cell lengths are different from each other are sequentially communicated with each other through the communication section to form a single gas path. In the gas analyzer described above, a first infrared transmitting / reflecting means 100 is provided adjacent to the light source 1, and a first measurement is performed on the infrared transmitting side of the first infrared transmitting / reflecting means 100. The second infrared transmitting / reflecting means 300 is provided via the cell 3, and the second infrared transmitting / reflecting means 300 is provided with a first infrared detector 5 on the infrared transmitting side and the infrared reflecting side, respectively. Third
While the infrared detector 12 is provided, the second measurement cell 7 is provided on the infrared reflection side of the first infrared transmission / reflection means 100.
A third infrared transmitting / reflecting means is provided through
The second infrared detector 9 and the fourth infrared detector 41 are provided on the infrared transmission side and the infrared reflection side of the infrared transmission / reflection means 300, respectively.

In the invention described in claim 7, for example, FIG.
As shown in Fig. 2, a plurality of measurement cells including cases where the cell lengths are different from each other are sequentially communicated via a communication section to form a single gas path, and an optical intermittent gas analyzer having a comparison cell is provided. And an optical interrupter C adjacent to the light source 1,
A comparison cell R and a first infrared transmitting / reflecting means B ₁ and a first measuring cell 3 and a second infrared transmitting / reflecting means B ₂ are arranged in parallel between the two-chamber light receiving type infrared detector M. The first infrared detector 5 is provided on the infrared reflection side of the _second infrared transmission / reflection means B ₂ while the first infrared detector 5 is provided on the infrared reflection side of the first infrared transmission / reflection means B _1. In addition, a second infrared detector 9 is provided via a second measuring cell 7 communicating with the first measuring cell 3.

According to the eighth aspect of the invention, as shown in FIG. 12, between the second infrared transmitting / reflecting means B ₂ and the first measuring cell 3 in the seventh aspect of the invention. 3 of an infrared transmission and reflection means B ₃ arranged, and the third infrared transmission and reflection means infrared reflection the on side first B ₃ of the measurement cell 3
The third measuring cell 23 communicating with the third measuring cell 23 is arranged, and the third infrared detecting means 12 corresponding to the third measuring cell 23 is provided.

In the invention described in claim 9, for example, FIG.
As shown in FIG. 7, at least a pair of infrared transmitting / reflecting means B ₄ and B ₅ are provided between the optical interrupter C and the comparison cell R in the invention according to claim 7 or 8, and one of them is provided. A second comparison cell R ₁ is provided on the infrared reflecting side of the infrared transmitting / reflecting means B ₄ , and the other infrared transmitting / reflecting means B _{5 is provided.}
A third measuring cell 23 communicating with the first measuring cell 3 and the second measuring cell 7 on the infrared reflection side of the second measuring cell 23 and the second measuring cell R ₁ and the third measuring cell 23. It is characterized in that another corresponding two-chamber light receiving infrared detector M ₁ is provided.

In the invention described in claim 10, for example, FIG.
As shown in FIG. 4, a plurality of measurement cells including cases where the cell lengths are different from each other are sequentially connected via a communication part to form a single gas path, and an intermittent optical gas analysis having a comparison cell is provided. An optical interrupter C adjacent to the light source 1 in the meter
And a two-chamber light receiving type infrared detector M, a first infrared transmitting / reflecting means B ₁ , a comparison cell R and a second infrared transmitting / reflecting means B ₂ which are arranged adjacent to each other in series. , Third infrared transmitting / reflecting means B ₃ arranged adjacent to each other in series, first
The measuring cell 3 and the fourth infrared transmitting / reflecting means B ₄ are provided in parallel, and the first infrared transmitting / reflecting means B ₁ ,
The infrared transmission and reflection means B ₂ and the third on the infrared reflection side of the infrared transmission and reflection means B _3, the second measuring cell 7 respectively communicating with the first measuring cell 3, the third Measuring cell 23
And a fourth measuring cell 37, and a second infrared detector 9, a third infrared detector 12, and a fourth infrared detector 32 corresponding to the respective measuring cells.

In the invention described in claim 11, for example, FIG.
As shown in claim 5, the first aspect of the invention of claim 10
Fifth measuring cell 47 communicating with the first measuring cell 3 on the infrared reflecting side of the fourth infrared transmitting / reflecting means B ₄ arranged adjacent to the measuring cell 3 of FIG. 47 and a corresponding fifth infrared detector 34 are provided.

According to the twelfth aspect of the invention, for example, FIG.
As shown in FIG. 5, one or a plurality of infrared transmitting / reflecting elements are provided between the fourth infrared transmitting / reflecting means B ₄ and the first measuring cell 3 in the invention according to claim 10 or 11. The means B ₅ is arranged adjacently, and the measuring cell 57 communicating with the first measuring cell 3 is arranged on the infrared reflecting side of the infrared transmitting / reflecting means B ₅ , and the measuring cell 57 is arranged.
It is characterized in that an infrared detecting means 44 corresponding to is provided.

The "measuring cell", "infrared transmitting / reflecting means" and "infrared detector" described in each of the above claims.
The name and the code do not unify or specify the configuration content, but include the case where the configuration content differs between the same name and the same code.

The invention according to claim 13 is characterized in that the infrared transmitting / reflecting means in the invention according to any one of claims 1 to 12 is an optical filter for separating infrared wavelengths. There is.

According to a fourteenth aspect of the invention, the infrared transmitting / reflecting means in the invention according to any one of the first to twelfth aspects is a half mirror or a beam splitter for dividing the amount of infrared light. Is characterized by.

[0023]

[Function] In a gas analyzer in which a plurality of cells including cells having different cell lengths are sequentially communicated through a communication section to form a single gas path,
By combining the reflection means and the infrared detector, both the fluid modulation (gas modulation) method and the light interrupting method can be easily configured with a single gas path, and multi-component measurement can be performed with high accuracy. be able to.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows N with a cell length (L ₂ ) of 60 mm.
₁ shows a gas analyzer (NDIR) 20 for two-component measurement in which an O _X measuring cell and a CO ₂ measuring cell having a cell length (L ₁ ) of 1 mm are connected in a single gas path. In the figure, cell length L
_A plurality of measuring cells 7 (second measuring cell) and 3 (first measuring cell) having different L ₁ and L ₂ are connected to each other through a communication portion 21 to form a single gas path. 1 is adjacent to a cut-on filter (optical filter) 100 as an infrared transmitting / reflecting unit that separates infrared wavelengths, and communicates with the infrared transmitting side and the infrared reflecting side of the optical filter 100 by communicating portions 21 respectively. has been cell length L ₂ of the NO _X measuring cell 3 and cell length L ₁ of the CO ₂ measuring cell 7 and the capacitor microphone has (NO _X for infrared detectors) 5 and pyroelectric detectors (CO ₂ for infrared detectors) 9 is provided. In this example, the sample gas 30 was used for the measurement cells 3 and 7.
And a reference gas (not shown) are alternately supplied.

Incidentally, although the cut-on filter 100 is built in the gas filter cell 22 in which the interference component gas is sealed in this embodiment, it is not always necessary to seal the interference component gas, and it can be set appropriately.

The measurement operation will be described below. The sample gas 30 (or reference gas) is the measurement cell 7
Through the communication part 21 to the measuring cell 3. The sample gas 30 may flow in the opposite direction. on the other hand,
The infrared light A emitted from the light source 1 is divided into reflected light A ₁ (λ ₁ ) and transmitted light A ₂ (λ ₂ ) by the cut-on filter 100 having the absorbance characteristic shown by the curve P in FIG.
That is, the reflected light A ₁ (λ ₁ ) is the absorption wavelength a of CO _2.
Has a short wavelength λ ₁ (≦ a) of (≈4.3 μm) or less,
Transmitted light A transmitted through the cut-on filter 100
₂ (λ ₂ ) has the other wavelength λ ₂ (> a).

In this transmitted light A ₂ , the cell length L ₂ is N of 60 mm through the CaF ₂ window 2 provided at one end side.
CaF that O _X measuring gas components of the measurement cell 3 while the measuring cell 3 through absorbs infrared, provided on the other side
By the NO band pass filter 400 having the absorbance characteristic shown by the curve Q in FIG. 8 through the _two windows 4, only the absorption wavelength b (≈5.3 μm) in the NO _X gas is transmitted to the NO _X detector 5. Reach On the other hand, the reflected light A ₁ passes through the CO ₂ measuring cell 7 through the CaF ₂ window 6 and is absorbed by the measurement component gas, and then passes through the CaF ₂ window 8 and the curve R in FIG.
CO ₂ bandpass filter 2 having the absorbance characteristic shown in
00, absorption wavelength a of CO ₂ gas (≈4.3 μm)
Only the light passes through and reaches the CO ₂ detector 9.

As described above, in this embodiment, the measurement component (NO
And CO ₂ ) are provided with two measuring cells 3 and 7 having cell lengths L ₂ and L ₁ respectively adapted to each other, and these measuring cells 3 and 7 are connected to each other to form a single gas path. The cut-on filter 100 is provided on the light source 1 side, and the measurement cells 3, which are connected to the infrared transmission side and the infrared reflection side of the cut-on filter 100 by the communication portions 21, respectively.
7 are arranged, and the detectors 5 and 9 are provided for each of the measuring cells 3 and 7, so that two measuring components (NO _x and CO ₂ ) having different cell lengths L ₂ and L _{1 that} are compatible with each other can be formed by a single path. Can measure with high accuracy.

FIG. 2 shows an NDIR 20 of a light-intermitting (light-modulating) system in which a rotating chopper (optical interrupter) C for interrupting infrared light from the light source 1 is provided between the light source 1 and the gas filter cell 22.
Then, the same two-component measurement as in the first embodiment is performed, and the second embodiment of the present invention is shown. Note that reference numeral 3
Reference numeral 3 is a comparison cell in which an inert gas such as N ₂ is sealed. In the comparison cell 33, infrared light from the light source 1 is not absorbed and a constant light quantity is always a two-chamber infrared detector. Reach 5. Therefore, the measurement cell 3 and the comparison cell 33
There is a difference in the amount of incident infrared rays, and since both infrared rays are interrupted by the rotary chopper 32, the condenser microphone in the infrared detector 5 vibrates. Be taken out the change in electrostatic capacitance caused by the vibration can handle it as a signal of the NO _X gas concentration.

FIG. 3 shows a third embodiment, in which a cut-on filter 100 for separating infrared wavelengths as a first infrared transmitting / reflecting means is provided on the light source 1 side, and the first optical filter 100 A communication part 21 is provided on each of the infrared transmission side and the infrared reflection side.
In communicated with the cell length L ₂ and the NO _X measuring cell 3 and cell length L ₁ of 60mm is 1mm of CO ₂ measuring cell 7 and N
An infrared detector 5 for O _{X and} an infrared detector 9 for CO ₂ are provided, and a NO _X bandpass as a second infrared transmitting / reflecting means is further provided between the NO _X measuring cell 3 and the NO _X infrared detector 5. the filter 300 is provided, and, while providing the infrared detector 5 for NO _X to the infrared transmission side of the NO _X band-pass filter 300, the NO _X bandpass infrared reflection side infrared detector 12 for SO ₂ in the filter 300 Provide 3 components (N
O, CO ₂ and SO ₂ ) are measured. In this embodiment, the NO _X bandpass filter 3 is used.
00 is contained in the gas filter cell 24 in which the interference component gas is sealed, but it is not always necessary to seal the interference component gas and can be set appropriately. In this embodiment to the seventh embodiment, the fluid modulation type NDIR 20 is used as in the case of the first embodiment.

The measurement operation will be described below. Measurement of three components (NO, CO ₂ and SO ₂ ) will be described with reference to FIG. This embodiment is characterized in FIG. 1, the transmitted light A ₂ in the first and second embodiments shown in FIG. 2 (lambda ₂₎ the reflected light A ₃
(Λ ₃ ) and transmitted light A ₄ (λ ₄ ) and reflected light A ₃ (λ
₃ ) and the transmitted light A ₄ are incident on the infrared detector 12 for SO ₂ and the infrared detector 5 for NO _x , respectively, so that the NO _x band pass filter (reflection spectrum) having the absorbance characteristic shown by the curve T in FIG. The point is that 300 is used. That is, the sample gas 30 (or reference gas) flows from the measurement cell 7 to the measurement cell 3 through the communication part 21. The sample gas 30 may flow in the opposite direction.

The transmitted light A ₂ (λ ₂ ) is reflected by the NO band-pass filter (reflection spectrum) 300 and reflected by the reflected light A 2.
_It is divided into ₃ (λ ₃ ) and transmitted light A ₄ (λ ₄ ). That is, the transmitted light A ₄ (λ ₄ ) has a wavelength λ ₄ (b−Δb ≦ λ ₄ ≦ b + Δb) in the range indicated by the region F in FIG. 10, and the NO band pass filter (reflection spectrum) 300
Reflected light A ₃ reflected the (lambda ₃₎ is the other wavelengths lambda ₃
(A <λ ₃ <b−Δb, b + Δb <λ ₃ ). Then, in this transmitted light A ₄ , C provided on one end side of the NO band pass filter (reflection spectrum) 300
Only the absorption wavelength b (= 5.3 μm) of the NO gas is transmitted through the NO bandpass filter 400 having the characteristic shown by the curve Q in FIG. 8 through the aF ₂ window 10 and the NO detector 5
Leading to. On the other hand, the reflected light A ₃ via a CaF ₂ window 11, the SO ₂ band-pass filter 500 having characteristics indicated by curve V in FIG. 10, the absorption wavelength c of SO ₂ gas (=
Only 7.3 μm) penetrates and reaches the SO ₂ detector 12.

FIG. 4 shows a fourth embodiment in which an auxiliary measuring cell 23 is provided on the infrared reflecting side of the second optical filter 300 to improve the sensitivity of the SO ₂ detector 12. The measuring cell 23 is communicated with the measuring cell 3 via the communicating portion 25. As a result, the cell length can be increased from (L ₂ ) in the third embodiment to (L ₂ + L ₃ ), and the cell length can be set longer, so that the sensitivity of the SO ₂ detector 12 can be increased.

FIG. 5 shows a fifth embodiment, in which one side (infrared transmission) of the first infrared transmitting / reflecting means 100 adjacent to the light source 1 side is provided with a NO _X bandpass filter (second red transmission). The external transmission / reflection means) 300 is provided, the measurement cell 7 and the infrared detector 9 are provided on the other (infrared reflection) side of the first infrared transmission / reflection means 100, and the second infrared transmission / reflection means is provided. Another measurement cell (third measurement cell, cell length L ₅ ) 47 and the infrared detector 12, which are in communication with the measurement cell 7 via the communication portion 26, are provided on one side (infrared reflection) 300 of 300, and
On the other (infrared transmitting) side of the second infrared transmitting / reflecting means 300, the measuring cell 3 and the infrared detector 5 which are communicated with the measuring cell 47 through the communicating portion 27 are provided to perform three-component measurement. It was done. In this embodiment, one side of the first infrared transmitting / reflecting means 100 is the infrared transmitting side and the second side is the second side.
Although one side of the infrared transmitting / reflecting means 300 is set to the infrared reflecting side respectively, one side of the first infrared transmitting / reflecting means 100 is set to the infrared reflecting side and the second red transmitting / reflecting means 300 is set to the infrared reflecting side. Outside transmission
One side of the reflection means 300 may be set to the infrared transmission side, respectively.

FIG. 6 shows a sixth embodiment, in which a measuring cell 3 and an infrared detector 5 are provided on the light source 1 side, and a cut-on filter (first infrared transmitting / reflecting means) 10 is provided between them 3 and 5.
0 and NO _X band-pass filter (second infrared-transmissive and
(Reflecting means) 300, and the second infrared transmitting / reflecting means 300 is connected to the first infrared transmitting / reflecting means 100.
The infrared detector 5 is provided in series on one side (infrared transmission) side, the infrared detector 5 is provided on one side (infrared transmission) side of the second infrared transmission / reflection means 300, and the first infrared transmission / reflection is performed. Means 1
00 is provided on the other side (infrared reflection) of 00 with the measurement cell 7 and the infrared detector 9 which communicate with the measurement cell 3 through the communication part 28, and the other side of the second infrared transmission / reflection means 300 (red). Measurement cell (cell length L ₅ ) 47 and the infrared detector 12 which are communicated with the measurement cell 7 via the communication part 29 on the (external reflection) side.
Is provided to measure three components. In this embodiment, the first infrared transmitting / reflecting means 100
One side is the infrared transmitting side, and the second infrared transmitting / reflecting means 3
Although one side of 00 is set to the infrared transmitting side respectively, one side of the first infrared transmitting / reflecting means 100 is set to the infrared reflecting side and the second infrared transmitting / reflecting means 300 is set to the infrared transmitting side. One side may be set to the infrared reflection side, respectively.

FIG. 7 shows a seventh embodiment. The NDIR 20 of the fluid modulation system of the third embodiment shown in FIG. 3 has a CO ₂ band pass filter 2 as a third infrared transmitting / reflecting means.
00 is added to add four components (NO, CO ₂ , SO ₂ and C
O) The measurement is performed.

In this embodiment, a cut-on filter (first infrared transmission /
(Reflecting means) 100 is provided, and the NO _x measuring cell 3 having a cell length L ₂ of 60 mm and the cell length L ₄ of 1 mm, which are connected to the infrared transmission side and the infrared reflection side of the cut-on filter 100 by the communication portion 21, respectively. CO ₂ measuring cell 77, NO _X infrared detector 5 and CO ₂ infrared detector 9 are provided,
Further, the NO _X measuring cell 3 and the NO NO for between infrared detector 5 _{X X} bandpass filter (second infrared transmission and reflection means) 300 is provided, and, NO _X infrared detector 5 N
While being provided on the infrared transmission side of the O bandpass filter 300, S is provided on the infrared reflection side of the NO _X bandpass filter 300.
The O ₂ for infrared detector 12 is provided, between the CO ₂ infrared detector 9 and CO ₂ measurement cell 77 is provided with a CO ₂ band-pass filter 200 having characteristics indicated by curve R in FIG. 9, CO
_The infrared detector 9 for _{2 is} used as a CO ₂ bandpass filter 200
Of the CO bandpass filter 6 on the infrared reflection side of the CO ₂ bandpass filter 200.
Infrared detector 41 for CO is provided via 00.

FIGS. 11 to 15 show an intermittent optical NDI.
Another embodiment of R20 will be shown.

FIG. 11 shows an eighth embodiment, in which a comparison cell R and a first infrared transmission are provided between an optical interrupter C adjacent to the light source 1 and a two-chamber light receiving infrared detector M. The reflecting means B ₁ and the first measuring cell 3 and the second infrared transmitting / reflecting means B ₂
Are provided in parallel, and the first infrared detector 5 is provided on the infrared reflection side of the _second infrared transmission / reflection means B _{2 while} the infrared reflection of the first infrared transmission / reflection means B ₁ is provided. A second measuring cell 7 communicating with the first measuring cell 3 on the side
Infrared detector 9 is provided.

FIG. 12 shows a ninth embodiment, in which a third infrared transmitting / reflecting means B ₃ is arranged between the second infrared transmitting / reflecting means B ₂ and the first measuring cell 3. In addition, the third measuring cell 23 communicating with the first measuring cell 3 is arranged on the infrared reflecting side of the third infrared transmitting / reflecting means B ₃ , and the third measuring cell 23 is provided. The third infrared detecting means 12 corresponding to the above is provided.

FIG. 13 shows a tenth embodiment, in which a pair of infrared transmitting / reflecting means B is provided between the optical interrupter C and the comparison cell R.
₄ , B ₅ are provided, the second comparison cell R ₁ is provided on the infrared reflection side of one of the infrared transmission / reflection means B ₄ , and the infrared reflection side of the other infrared transmission / reflection means B ₅ is provided. Is provided with a third measuring cell 23 communicating with the first measuring cell 3 and the second measuring cell 7, and the second measuring cell R ₁ and the third measuring cell 23 are provided.
A separate two-chamber light-receiving infrared detector M ₁ corresponding to the measuring cell 23 of FIG. 2 is provided, and two infrared-transmissive infrared detectors M ₁ are provided between the first measuring cell 3 and the two-chamber light-receiving infrared detector M. Reflecting means B ₂ and B ₃ are provided, and the fourth and fifth measuring cells 37 and 47 and infrared detectors 32 and 34 are arranged on the infrared reflecting side thereof. In this case, the sample gas flows from the fourth measuring cell 37 to the fifth, first, third, and second measuring cells 7, but the reverse direction may be used.

FIG. 14 shows an eleventh embodiment, which is an optical interrupter C adjacent to the light source 1 and a two-chamber light receiving infrared detector M.
Between the first infrared transmission and
The reflecting means B ₁ , the comparison cell R and the second infrared transmitting / reflecting means B ₂ , the third infrared transmitting / reflecting means B ₃ arranged adjacent to each other in series, the first measuring cell 3 and the fourth measuring cell 3 The infrared transmitting / reflecting means B ₄ is provided in parallel, and the first infrared transmitting / reflecting means B ₁ , the second infrared transmitting / reflecting means B ₂ and the third infrared transmitting / reflecting means B _{3 are provided.} A second measurement cell 7, a third measurement cell 23 and a fourth measurement cell 37, which communicate with the first measurement cell 3 on the respective infrared reflection sides of
The second infrared detector 9, the third infrared detector 12, and the fourth infrared detector 32 corresponding to each measurement cell are provided.

FIG. 15 shows a fifth infrared transmitting / reflecting means B between the _fourth infrared transmitting / reflecting means B ₄ and the first measuring cell 3.
₅ are arranged adjacent to each other, and measuring cells 47 and 57 communicating with the first measuring cell 3 are provided on the infrared reflecting sides of the fourth and fifth infrared transmitting / reflecting means B ₄ and B ₅ , respectively. In addition to the arrangement, infrared measuring means 34, 44 corresponding to the measuring cells 47, 57 are provided.

The operation and effect of each of the embodiments shown in FIGS. 11 to 15 are basically the same as those of each of the embodiments shown in FIGS. 1 to 7, and the description thereof will be omitted. The present invention is not limited to the above embodiments,
It goes without saying that the combination of the infrared transmitting / reflecting means, the measuring cell and the infrared detector may be appropriately changed and set according to the above-mentioned respective embodiments. It should be noted that the illustrated cell length L ₁ ,
Each code of ... does not specify its "length", but indicates the case where the lengths of the respective measurement cells are different.

Thus, in each of the above-mentioned embodiments,
Each measuring component is provided with a measuring cell having a cell length suitable for each measuring component, and these measuring cells are connected to each other to form a single gas path, while one or more infrared transmitting / reflecting means are provided on the light source side. Since each of the measurement cells that are in communication with each other on the infrared transmission side and the infrared reflection side of the infrared transmission / reflection means is connected by a communication unit, and an infrared detector is provided for each measurement cell, Multiple measurement components of different concentrations can be measured with a single gas path.

In the above embodiment, infrared transmission /
Although the one using the optical filter for separating the infrared wavelength is shown as the reflecting means, a half mirror or a beam splitter for dividing the infrared light amount may be used. In this case, it is preferable that the transmitting / reflecting surface be provided in the gas filter cell with an inclination angle of 45 ° with respect to the optical axis of each cell.

The splitting ratio of the amount of light to each detector by the beam splitter is usually 1: 1. However, if there is a sensitivity difference peculiar to the detectors, the one with adjusted reflectance is used. Using a ratio of 1: 2 or higher,
The amount of light is distributed according to the detection sensitivity of each detector.

[0048]

As described above, according to the present invention,
A measurement cell having a cell length suitable for each concentration and each measurement component is provided, and a single gas path is formed by connecting these measurement cells to each other, and infrared transmission / reflection means is provided on the light source side. Each of the measurement cells, which are communicated with each other by a communication section, is arranged on the infrared transmission side and the infrared reflection side of the infrared transmission / reflection means, and an infrared detector is provided for each measurement cell. There is an effect that a plurality of measurement components having different lengths can be measured with high accuracy by a simple configuration of a single gas path.

[Brief description of drawings]

FIG. 1 is a structural explanatory view showing a first embodiment of the present invention.

FIG. 2 is a structural explanatory view showing a second embodiment of the present invention.

FIG. 3 is a structural explanatory view showing a third embodiment of the present invention.

FIG. 4 is a structural explanatory view showing a fourth embodiment of the present invention.

FIG. 5 is a structural explanatory view showing a fifth embodiment of the present invention.

FIG. 6 is a structural explanatory view showing a sixth embodiment of the present invention.

FIG. 7 is a structural explanatory view showing a seventh embodiment of the present invention.

FIG. 8 is a characteristic diagram showing wavelength spectral characteristics of infrared transmitting / reflecting means used in the present invention.

FIG. 9 is a characteristic diagram similarly showing wavelength spectral characteristics of the infrared transmitting / reflecting means used in the present invention.

FIG. 10 is a characteristic diagram showing wavelength spectral characteristics of the infrared transmitting / reflecting means used in the present invention.

FIG. 11 is a structural explanatory view showing an eighth embodiment of the present invention.

FIG. 12 is a structural explanatory view showing a ninth embodiment of the present invention.

FIG. 13 is a structural explanatory view showing a tenth embodiment of the present invention.

FIG. 14 is a structural explanatory view showing an eleventh embodiment of the present invention.

FIG. 15 is a structural explanatory view showing a twelfth embodiment of the present invention.

[Explanation of symbols]

1 ... Light source, 3, 7, 23, 37, 47, 57, 67, 7
7 ... Measuring cell, 5, 9, 12, 32, 34, 41, 4
4, M, M ₁ ... Infrared detector 21,25,26,2
7, 28, 29 ... Communication part, 100, 200, 300, B
₁ , B ₂ , B ₃ , B ₄ , B ₅ ... Infrared transmitting / reflecting means, C
… Optical interrupter, R, R ₁ … Comparison cell.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Naoto Shimizu Inventor, 2 Higashimachi, Kichijoin Miya, Minami-ku, Kyoto City, Kyoto Prefecture Horiba Manufacturing Co., Ltd. Inside HORIBA, Ltd. (72) Inventor Toshikazu Onishi 2 Higashimachi, Kichijoingu, Minami-ku, Kyoto-shi, Kyoto Inside HORIBA, Ltd.

Claims (14)

[Claims] 1. A gas analyzer in which a plurality of measuring cells including cells having different cell lengths are sequentially communicated with each other through a communicating section to form a single gas path, and a red gas is provided adjacent to a light source. External transmission / reflection means is provided, and at least one set of measurement cells connected to the infrared transmission side and infrared reflection side of the infrared transmission / reflection means by the communication section and infrared rays corresponding to the measurement cells, respectively. A gas analyzer equipped with a detector. 2. A gas analyzer in which a plurality of measuring cells including cases where cell lengths are different from each other are sequentially communicated through a communication section to form a single gas path, and the gas analyzer is adjacent to a light source. 1 infrared transmitting / reflecting means is provided, and the first measuring cell and the second measuring cell which are respectively connected to the infrared transmitting side and the infrared reflecting side of the first infrared transmitting / reflecting means by the communicating portion. A measuring cell is provided, and second infrared transmitting / reflecting means is provided between the first measuring cell and the first infrared detector corresponding to the first measuring cell, and the second red transmitting / reflecting means is provided. A gas analyzer characterized in that a third infrared detector is provided on the infrared reflection side of the external transmission / reflection means, while a second infrared detector corresponding to the second measurement cell is provided. 3. A third measuring cell is interposed between an infrared reflecting side of the first infrared transmitting / reflecting means and a third infrared detector. Gas analyzer described. 4. A gas analyzer in which a plurality of measuring cells including cases where the cell lengths are different from each other are sequentially connected via a communication part to form a single gas path, and the gas analyzer is adjacent to a light source. 1 infrared transmitting / reflecting means and a second infrared transmitting / reflecting means connected in series to the infrared transmitting side of the 1st infrared transmitting / reflecting means. A first measuring cell and a first infrared detector corresponding to the first measuring cell are provided on the infrared transmitting side of the means, and a second measuring cell is provided on the infrared reflecting side of the first infrared transmitting / reflecting means. Second measuring cell and a second infrared detector corresponding to the second measuring cell are provided, and the third measuring cell and the third measuring cell are provided on the infrared reflecting side of the second infrared transmitting / reflecting means. A gas analyzer comprising a third infrared detector corresponding to the cell. 5. A gas analyzer in which a plurality of measuring cells including cases where the cell lengths are different from each other are sequentially connected via a communication part to form a single gas path, wherein a light source and a first red light are provided. A first measuring cell is provided between the external transmission / reflection means, a second infrared transmission / reflection means is provided on the infrared transmission side of the first infrared transmission / reflection means, and a second measurement cell is provided. Infrared transmission
A first infrared detector is provided on the infrared transmitting side of the reflecting means, while a second measuring cell and its second measuring cell are provided on the infrared reflecting side of the first infrared transmitting / reflecting means. A second infrared detector is provided, and a third measurement cell and a third infrared detector corresponding to the third measurement cell are provided on the infrared reflection side of the second infrared transmission / reflection means. A gas analyzer characterized in that 6. A gas analyzer in which a plurality of measuring cells including cases where the cell lengths are different from each other are sequentially connected via a communication part to form a single gas path, and the gas analyzer is adjacent to a light source. The first infrared transmission / reflection means is provided, and the second infrared transmission / reflection means is provided on the infrared transmission side of the first infrared transmission / reflection means via the first measurement cell. The infrared transmitting side and the infrared reflecting side of the second infrared transmitting / reflecting means are respectively provided with the first
While providing the infrared detector and the third infrared detector of
A third infrared transmitting / reflecting means is provided on the infrared reflecting side of the first infrared transmitting / reflecting means via the second measuring cell, and the infrared of the third infrared transmitting / reflecting means is provided. A gas analyzer, wherein a second infrared detector and a fourth infrared detector are provided on the transmission side and the infrared reflection side, respectively. 7. An optical interrupting gas analyzer having a comparison cell, wherein a plurality of measuring cells including cells having different cell lengths are sequentially communicated with each other through a communication section to form a single gas path and having a comparison cell. The comparison cell, the first infrared transmitting / reflecting means, the first measuring cell, and the second red are provided between the optical interrupter adjacent to the light source and the two-chamber light receiving infrared detector. External transmission / reflection means are provided in parallel, and a first infrared detector is provided on the infrared reflection side of the second infrared transmission / reflection means, while infrared rays of the first infrared transmission / reflection means are provided. A gas analyzer characterized in that a second infrared detector is provided on the reflection side via a second measurement cell communicating with the first measurement cell. 8. A third infrared transmitting / reflecting means is arranged between the second infrared transmitting / reflecting means and the first measuring cell,
In addition, a third measurement cell communicating with the first measurement cell is arranged on the infrared reflection side of the third infrared transmission / reflection means, and a third measurement cell corresponding to the third measurement cell is arranged.
8. The gas analyzer according to claim 7, wherein the infrared detecting means is provided. 9. A pair of infrared transmission / reflection means is provided between the optical interrupter and the comparison cell, and a second comparison cell is provided on the infrared reflection side of one of the infrared transmission / reflection means. A third measuring cell communicating with the first measuring cell and the second measuring cell is provided on the infrared reflecting side of the other infrared transmitting / reflecting means, and the second comparing cell and the third comparing cell are provided. 9. The gas analyzer according to claim 7 or 8, further comprising another infrared detector of a two-chamber light receiving type corresponding to the measurement cell. 10. A photointerruption type gas analyzer having a comparison cell, wherein a plurality of measurement cells including cells having different cell lengths are sequentially communicated with each other through a communication section to form a single gas path and having a comparison cell. The first infrared transmitting / reflecting means, the comparison cell, and the second infrared transmitting / reflecting means arranged in series adjacent to each other between the optical interrupter adjacent to the light source and the two-chamber light receiving infrared detector.
The infrared transmitting / reflecting means, the third infrared transmitting / reflecting means, the first measuring cell and the fourth infrared transmitting / reflecting means, which are arranged adjacent to each other in series, are provided in parallel to each other, and A second measurement cell communicating with the first measurement cell on each of the infrared reflection sides of the infrared transmission / reflection means, the second infrared transmission / reflection means, and the third infrared transmission / reflection means, A third measuring cell and a fourth measuring cell, and a second measuring cell corresponding to each measuring cell.
The infrared analyzer, the third infrared detector, and the fourth infrared detector are provided. 11. A fifth measurement cell communicating with the first measurement cell on the infrared reflection side of a fourth infrared transmission / reflection means arranged adjacent to the first measurement cell, and a fifth measurement cell thereof. The gas analyzer according to claim 10, further comprising a fifth infrared detector corresponding to each of the measurement cells. 12. The fourth infrared transmitting / reflecting means and the first infrared transmitting / reflecting means.
One or a plurality of infrared transmitting / reflecting means are arranged adjacent to the measuring cell and the infrared transmitting side of the infrared transmitting / reflecting means communicates with the first measuring cell. The gas analyzer according to claim 10 or 11, wherein the cell is arranged and an infrared ray detecting means corresponding to the measuring cell is provided. 13. The gas analyzer according to claim 1, wherein the infrared transmitting / reflecting means is an optical filter that disperses infrared wavelengths. 14. The gas analyzer according to claim 1, wherein the infrared transmitting / reflecting means is a half mirror or a beam splitter that divides the amount of infrared light.