JPH09101284A - Method and instrument for measuring carbon monoxide concentration - Google Patents

Method and instrument for measuring carbon monoxide concentration

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Publication number
JPH09101284A
JPH09101284A JP7259728A JP25972895A JPH09101284A JP H09101284 A JPH09101284 A JP H09101284A JP 7259728 A JP7259728 A JP 7259728A JP 25972895 A JP25972895 A JP 25972895A JP H09101284 A JPH09101284 A JP H09101284A
Authority
JP
Japan
Prior art keywords
carbon dioxide
carbon monoxide
carbon
sample gas
concentration
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP7259728A
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Japanese (ja)
Other versions
JP3139672B2 (en
Inventor
Hozumi Nita
穂積 二田
Takayuki Suzuki
隆之 鈴木
Hironori Hatano
博憲 波多野
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Yazaki Corp
Original Assignee
Yazaki Corp
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Filing date
Publication date
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Priority to JP07259728A priority Critical patent/JP3139672B2/en
Publication of JPH09101284A publication Critical patent/JPH09101284A/en
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Publication of JP3139672B2 publication Critical patent/JP3139672B2/en
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Expired - Fee Related legal-status Critical Current

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Abstract

PROBLEM TO BE SOLVED: To measure the carbon monoxide concentration of a sample gas without being influenced by other combustible gas components by converting the carbon monoxide in the sample gas into carbon dioxide after removing the carbon dioxide originally contained in the sample gas. SOLUTION: The carbon dioxide contained in a sample gas which is brought into contact with the sensor section of a carbon monoxide concentration measuring instrument is removed by providing a carbon dioxide removing agent of soda lime, etc., in a layered state. When the sample gas contains ethanol and butane, the sample gas is led to a carbon monoxide-to-carbon dioxide converting means after the ethanol and butane are completely removed by providing an activated carbon layer in the preceding or succeeding state of the carbon dioxide removing section. When the sample gas contains a methane gas, in addition, the influence of hydrogen gas is removed by using a catalyst layer containing a platinum catalyst together with the converting means. Then the carbon monoxide contained in the sample gas from which the carbon dioxide is removed in advance is converted into equimolar carbon dioxide by catalytically oxidizing the carbon monoxide through a catalytic oxidation process. When the carbon dioxide is measured, the carbon monoxide concentration of the sample gas can be measured without being influenced by other combustible gas components.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、試料ガス中の一酸
化炭素の濃度を測定する測定方法及びに関する。
TECHNICAL FIELD The present invention relates to a measuring method and method for measuring the concentration of carbon monoxide in a sample gas.

【0002】[0002]

【従来の技術】従来、一酸化炭素濃度測定器における一
酸化炭素センサ素子としては、図8にその断面を示すよ
うな固体電解質型センサ素子が知られていた。図中符号
31はジルコニア固体電解質、符号32a及び32bは
白金若しくは金からなるガス透過性を有する電極、また
符号33は貴金属酸化触媒を有する層であって、上記電
極32b表面にコーティングされている。
2. Description of the Related Art Conventionally, as a carbon monoxide sensor element in a carbon monoxide concentration measuring device, a solid electrolyte type sensor element having a cross section shown in FIG. 8 has been known. In the figure, reference numeral 31 is a zirconia solid electrolyte, reference numerals 32a and 32b are gas permeable electrodes made of platinum or gold, and reference numeral 33 is a layer having a noble metal oxidation catalyst, which is coated on the surface of the electrode 32b.

【0003】この従来技術にかかる一酸化炭素センサ素
子は、その固体電解質層はイオン導電性を有するよう加
熱して使用される。このセンサ素子が一酸化炭素等の可
燃性ガスを含有する雰囲気に置かれたとき、触媒層33
を有する電極32bでは、雰囲気中の可燃性ガスがその
触媒層33によって酸化除去されるため、電極32bに
対する影響は小さく、一方の電極32aにおいては可燃
性ガスと反応して電荷が変動し、その結果これら電極3
2a及び32b間に起電力が生じる。ここで、この触媒
層33中の触媒を適宜選択することにより、センサ素子
のガス選択性を持たせることが可能である。しかし、測
定対象ガスが一酸化炭素の場合、水素ガスによるノイズ
が大きく、その影響を除去することが非常に困難であっ
た。
The carbon monoxide sensor element according to this prior art is used by heating the solid electrolyte layer so as to have ionic conductivity. When this sensor element is placed in an atmosphere containing a flammable gas such as carbon monoxide, the catalyst layer 33
In the electrode 32b having, the combustible gas in the atmosphere is oxidized and removed by the catalyst layer 33, so that the influence on the electrode 32b is small, and in one electrode 32a, the charge fluctuates by reacting with the combustible gas. Results these electrodes 3
An electromotive force is generated between 2a and 32b. Here, the gas selectivity of the sensor element can be provided by appropriately selecting the catalyst in the catalyst layer 33. However, when the measurement target gas is carbon monoxide, noise due to hydrogen gas is large, and it is very difficult to remove the influence.

【0004】[0004]

【発明が解決しようとする課題】本発明は従来技術の上
記問題点を解決する、すなわち、他の燃焼性ガス成分の
影響を受けずに測定できる一酸化炭素濃度測定方法を提
供することを特徴とする。
SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, that is, provides a carbon monoxide concentration measuring method capable of measuring without being affected by other combustible gas components. And

【0005】[0005]

【課題を解決するための手段】本発明の一酸化炭素濃度
測定方法は、請求項1に記載のように、試料ガスから二
酸化炭素を除去した後、該ガス中の一酸化炭素を二酸化
炭素に転換し、次いでこの転換された二酸化炭素の濃度
を測定することにより一酸化炭素濃度を検知する構成を
有する。
According to the method of measuring carbon monoxide concentration of the present invention, carbon dioxide is removed from a sample gas and then carbon monoxide in the gas is converted into carbon dioxide. After the conversion, the carbon monoxide concentration is detected by measuring the concentration of the converted carbon dioxide.

【0006】[0006]

【発明の実施の形態】本発明の一酸化炭素濃度測定方法
において、試料ガス中の一酸化炭素を二酸化炭素に変換
する方法としてに触媒酸化法を用いるならば、非常にコ
ンパクトな測定器とすることができ、また、メンテナン
ス等の手間が不要であり、かつ、低コスト等の利点を有
するので好ましい。
BEST MODE FOR CARRYING OUT THE INVENTION In the carbon monoxide concentration measuring method of the present invention, if a catalytic oxidation method is used as a method for converting carbon monoxide in a sample gas into carbon dioxide, a very compact measuring device is obtained. This is preferable because it can be performed, and it does not require maintenance and the like and has advantages such as low cost.

【0007】ソーダ石灰、或いはアスカライト等の二酸
化炭素除去剤を層状に設け、あるいは、これらからなる
カラムを設けることにより測定器のセンサ部に接触する
試料ガス中の二酸化炭素を除去することができる。この
とき、二酸化炭素を完全に除去することが測定精度上必
要である。
By providing a carbon dioxide removing agent such as soda lime or ascarite in a layered manner, or by providing a column composed of these, carbon dioxide in the sample gas contacting the sensor portion of the measuring instrument can be removed. . At this time, it is necessary to completely remove carbon dioxide in terms of measurement accuracy.

【0008】なお、試料ガス中にエタノール、ブタン、
或いはプロパンが含有されている場合には、上記炭酸ガ
ス除去部の前段或いは後段として、適当量の活性炭から
なる活性炭層を設けて、これらを完全に除去したのち、
一酸化炭素−二酸化炭素転換手段に導入することによ
り、対応することが可能である。
In the sample gas, ethanol, butane,
Alternatively, when propane is contained, an activated carbon layer made of an appropriate amount of activated carbon is provided as a pre-stage or a post-stage of the carbon dioxide gas removing section, and after completely removing them,
It is possible to deal with this by introducing it into the carbon monoxide-carbon dioxide conversion means.

【0009】一方、メタンガスが試料ガス中に含有され
ている場合には、一酸化炭素−二酸化炭素変換手段で、
白金或いはロジウム触媒を含有する触媒層を用いること
により、水素ガスの影響を除去することが可能である。
予め二酸化炭素除去手段により二酸化炭素が除去された
試料ガス中に含有されている一酸化炭素は、これら触媒
によって接触酸化されて等モルの二酸化炭素に転換され
るため、その二酸化炭素濃度を測定することにより、試
料ガス中に含有されている一酸化炭素濃度を検知するこ
とができる。
On the other hand, when methane gas is contained in the sample gas, carbon monoxide-carbon dioxide conversion means,
By using a catalyst layer containing a platinum or rhodium catalyst, it is possible to remove the influence of hydrogen gas.
Since carbon monoxide contained in the sample gas from which carbon dioxide has been removed by the carbon dioxide removing means in advance is catalytically oxidized by these catalysts and converted into equimolar carbon dioxide, its carbon dioxide concentration is measured. Thus, the concentration of carbon monoxide contained in the sample gas can be detected.

【0010】なお、試料ガス中に含有されている水素ガ
スは、これら触媒によって酸化されて水蒸気となるが、
二酸化炭素測定器のセンサ部として水蒸気に対して感度
を持たないので、水素ガスによるノイズを防止すること
ができる。
The hydrogen gas contained in the sample gas is oxidized by these catalysts into water vapor.
Since the sensor part of the carbon dioxide measuring device has no sensitivity to water vapor, noise due to hydrogen gas can be prevented.

【0011】[0011]

【実施例】【Example】

〔実施例1〕図1に本発明の二酸化炭素測定手段である
二酸化炭素濃度センサ素子Aの断面図を示す。このもの
は固体電解質としてNASICON(Na1+X Zr2
3-X SiX 12、xは1または2)を用いる固体電解質
型二酸化炭素濃度センサ素子であり、図中符号1はNA
SICON層である。このNASICON層1の両側面
には符号2a及び2bで示される白金製のガス透過性電
極が密着している。この電極2aにはリチウム及びバリ
ウムの混合炭酸塩からなる層4が配されており、他方の
電極2bには基板7を挟んで白金製ヒーター6が配され
ており、このヒーター6によってセンサ全体が固体電解
質層であるNASICON層の電荷移動に最適な温度
(本実施例においては400℃)に昇温される。なお、
基板7は多孔質のシリカアルミナ製であるため、ガス透
過性を有する。
 [Embodiment 1] FIG. 1 shows a carbon dioxide measuring means of the present invention.
A sectional view of carbon dioxide concentration sensor element A is shown. This one
NASICON (Na1 + XZrTwoP
3-XSiXO 12, X is a solid electrolyte using 1 or 2)
Type carbon dioxide concentration sensor element, reference numeral 1 in the drawing is NA
It is a SICON layer. Both sides of this NASICON layer 1
Is a gas permeable electrode made of platinum indicated by reference numerals 2a and 2b.
The poles are in close contact. This electrode 2a has lithium and burrs.
There is a layer 4 of mixed carbonate of um and the other
A platinum heater 6 is arranged on the electrode 2b with a substrate 7 interposed therebetween.
The whole sensor is solid electrolytic by this heater 6.
Optimum temperature for charge transfer in NASICON layer
The temperature is raised to (400 ° C. in this embodiment). In addition,
Since the substrate 7 is made of porous silica-alumina, it is gas-permeable.
It is transient.

【0012】上記二酸化炭素濃度センサ素子Aは、その
電極2a及び電極2bの間に周囲の雰囲気の二酸化炭素
濃度に応じた起電力が生じ、その起電力によって二酸化
炭素濃度濃度を検出するものである。この二酸化炭素濃
度センサ素子Aにおいて、二酸化炭素濃度の起電力への
影響を調べた。その結果を図2に示す。
The carbon dioxide concentration sensor element A produces an electromotive force according to the carbon dioxide concentration of the surrounding atmosphere between the electrodes 2a and 2b, and detects the carbon dioxide concentration by the electromotive force. . In this carbon dioxide concentration sensor element A, the effect of carbon dioxide concentration on electromotive force was examined. The result is shown in FIG.

【0013】次いで、この二酸化炭素濃度センサ素子A
の周囲に、多孔質シリカからなる固定材5を介して、一
酸化炭素−二酸化炭素転換手段である5重量%の酸化パ
ラジウム(II)を触媒として担持含有するアルミナから
なる触媒層3を配した(図3参照、以下「センサ素子
A’」と云う)。なお、この触媒層3は、センサ素子A
のヒーター6の働きにより昇温されているため、試料ガ
ス中の一酸化炭素を容易・確実に二酸化炭素へ転換す
る。
Next, this carbon dioxide concentration sensor element A
A catalyst layer 3 made of alumina containing 5% by weight of palladium (II) oxide as a catalyst, which is a carbon monoxide-carbon dioxide conversion means, was disposed around the periphery of the fixing material 5 made of porous silica. (See FIG. 3, hereinafter referred to as “sensor element A ′”). In addition, the catalyst layer 3 is formed by the sensor element A.
Since the temperature is raised by the function of the heater 6 of, the carbon monoxide in the sample gas is easily and surely converted to carbon dioxide.

【0014】上記触媒層を配したセンサ素子A’を図4
中符号9で示される吸引チェンバーに格納し、そのガス
入口に二酸化炭素除去手段として粒状のソーダ石灰20
gを充填したカラムであるソーダ石灰フィルター8、及
び、吸引チェンバー8のガス出口に吸引ポンプ10を接
続し、一酸化炭素濃度測定器(以下「吸引式一酸化炭素
濃度測定器」とも云う)B(実施例1)とした。
FIG. 4 shows a sensor element A ′ having the above catalyst layer.
It is stored in a suction chamber indicated by medium code 9, and granular soda lime 20 is provided at its gas inlet as carbon dioxide removing means.
A suction pump 10 is connected to the soda lime filter 8 which is a column filled with g and the gas outlet of the suction chamber 8 to measure a carbon monoxide concentration (hereinafter also referred to as a "suction type carbon monoxide concentration measuring device") B. (Example 1).

【0015】このポンプ10によって吸引されることに
よって、試料ガスはソーダ石灰フィルター8を通過し吸
引チェンバー9に導入されるが、その間、ソーダ石灰に
よって試料ガス中の二酸化炭素が除去される。吸引チェ
ンバーに導入されたガス中の一酸化炭素は、チェンバー
内9に設置されたセンサ素子A’周囲に配された触媒層
3により二酸化炭素に転換され、次いで、生成した二酸
化炭素の濃度がセンサ素子A’に内包される二酸化炭素
センサ素子Aによって計測される。なお、前述のように
一酸化炭素の二酸化炭素への転換は等モルで進行するた
め、センサ素子Aで測定された二酸化炭素濃度により、
演算することなく一酸化炭素濃度を求めることができ
る。
By being sucked by the pump 10, the sample gas passes through the soda-lime filter 8 and is introduced into the suction chamber 9, while carbon dioxide in the sample gas is removed by the soda-lime. Carbon monoxide in the gas introduced into the suction chamber is converted into carbon dioxide by the catalyst layer 3 disposed around the sensor element A ′ installed in the chamber 9, and then the concentration of the generated carbon dioxide is detected by the sensor. It is measured by the carbon dioxide sensor element A included in the element A ′. As described above, since the conversion of carbon monoxide to carbon dioxide proceeds equimolarly, the carbon dioxide concentration measured by the sensor element A causes
The carbon monoxide concentration can be calculated without any calculation.

【0016】なお、測定器Bにおいて空気(一般に大気
中の二酸化炭素濃度は300〜400ppmと云われて
いる)を対象ガスとして、ソーダ石灰フィルター8をは
ずしたときと装着したときのそれぞれの出力値(二酸化
炭素濃度)を測定したところ、フィルター7なしの条件
での検出値が400ppm程度(図2において点線
(b)に該当する)であったが、フィルター7を付けて
1時間後の検出値は8ppm程度(図2において点線
(a)に該当する)となり、本発明に係る測定器Bでは
二酸化炭素の影響をほぼ完全に排除できることが確認さ
れた。
In the measuring instrument B, air (generally speaking, the carbon dioxide concentration in the atmosphere is said to be 300 to 400 ppm) is used as the target gas, and the output values when the soda-lime filter 8 is removed and when it is installed. When the (carbon dioxide concentration) was measured, the detected value without the filter 7 was about 400 ppm (corresponding to the dotted line (b) in FIG. 2), but the detected value 1 hour after the filter 7 was attached Was about 8 ppm (corresponding to the dotted line (a) in FIG. 2), and it was confirmed that the measuring instrument B according to the present invention can almost completely eliminate the influence of carbon dioxide.

【0017】なお、測定器Bにおいて、別途1%の高濃
度の二酸化炭素を含有する空気を用いてその影響を調査
したが、その出力のベースはほぼ安定していた。
In the measuring instrument B, the effect was investigated separately by using air containing a high concentration of carbon dioxide of 1%, but the output base was almost stable.

【0018】ここで、この測定器Bのソーダ石灰フィル
ター8について、その寿命を調べた。すなわち、2月間
空気を連続的に吸引して、その後この測定器の測定値へ
の二酸化炭素の影響について調べたが、測定値には二酸
化炭素の影響が殆どないことが判り、実用上充分な寿命
を持つものと考えられる。
Here, the life of the soda lime filter 8 of the measuring instrument B was examined. That is, air was continuously sucked in for 2 months, and then the influence of carbon dioxide on the measurement value of this measuring device was investigated, but it was found that there was almost no influence of carbon dioxide on the measurement value. It is considered to have a lifetime.

【0019】なお、この測定器Bの一酸化炭素1ppm
の最大分解能は図2により判るように4mVに相当する
ため、含有する一酸化炭素の濃度が1ppmの試料ガス
でも充分測定可能であり、優れたセンサである(図5
に、この測定器Bの一酸化炭素濃度に対する出力特性を
示す)。ただし、この測定器Bは測定値が安定するまで
に1時間程度要すると云う欠点があるが、これは、測定
開始直後はその出力変化が大きいものの、その後は徐々
に変化量が減少し1時間後に安定する性質を利用して、
次のようにすることにより、実用上測定に差し支えなく
用いることができる。
In addition, carbon monoxide of 1 ppm in this measuring device B
As can be seen from FIG. 2, the maximum resolving power of 1 is equivalent to 4 mV, so that even a sample gas containing 1 ppm of carbon monoxide can be sufficiently measured and is an excellent sensor (FIG. 5).
The output characteristics of the measuring instrument B with respect to the carbon monoxide concentration are shown in FIG. However, this measuring instrument B has a drawback that it takes about 1 hour until the measured value stabilizes. This is because the output change is large immediately after the start of measurement, but after that, the amount of change gradually decreases and it decreases for 1 hour. Utilizing the property of stabilizing later,
By the following, it can be practically used without any problem.

【0020】即ち、様々な一酸化炭素濃度ガスを用い
て、測定開始後任意の時間(実用上、10分以降)にお
いて、測定開始時間における単位時間の感度変化量を予
め調べておき、飽和出力値(例えば飽和出力値は通電開
始後1時間程度で到達する。)との相関から得られる係
数を時間(測定開始)毎に更新させる補正を行うことに
よって、迅速で、かつ、通常においては充分な分解能
(70ppm程度の一酸化炭素含有のガスにおいて、一
酸化炭素1ppmで0.7mV程度の分解能)を有する
実用的な一酸化炭素濃度測定器とすることができる。
That is, using various carbon monoxide concentration gases, the sensitivity change amount per unit time at the measurement start time is investigated in advance at an arbitrary time after the start of the measurement (practically 10 minutes or more), and the saturated output is measured. The coefficient obtained from the correlation with the value (for example, the saturated output value reaches about 1 hour after the start of energization) is updated quickly and normally in a sufficient manner by performing correction to update it every time (start of measurement). It is possible to provide a practical carbon monoxide concentration measuring instrument having a high resolution (in a gas containing carbon monoxide of about 70 ppm, a resolution of about 0.7 mV at 1 ppm of carbon monoxide).

【0021】なお、上記推定手段としては、出力の時間
変化を監視してその結果からデーターベースが蓄えられ
たメモリから一酸化濃度を演算・推定する中央制御回
路、データーベースが蓄えられたメモリ等により構成す
ることができる。また、測定開始一定時間過後の出力値
を測定値として用いても充分な精度が得られる用途にお
いては、上記のような推定手段が不要であり、その場合
は簡便である。
As the estimating means, a central control circuit for monitoring the time change of the output and calculating / estimating the concentration of monoxide from the memory in which the database is stored based on the result, a memory in which the database is stored, etc. It can be configured by. Further, in applications where sufficient accuracy can be obtained even if the output value after a lapse of a certain time after the start of measurement is used as the measured value, the above estimation means is unnecessary, and in that case it is simple.

【0022】〔実施例2〕以上、吸引式一酸化炭素濃度
測定器Bについて述べたが、次に本発明の別の実施例で
ある拡散式一酸化炭素濃度測定器Cについて述べる。図
6にその図を示す。即ち、実施例1でセンサ素子A’と
して用いたのと同じセンサ素子を2つ(それぞれA’
α、A’βと云う)を有底の円筒(それぞれカラム11
α及びカラム11βと云う)の底部に設置し、そのカラ
ムの口側に粒状のソーダ石灰5gを充填したものを2つ
作製した。次いで、カラム11βの開口部に常温で一酸
化炭素や水素ガスを酸化燃焼させる白金系酸化触媒(エ
ヌイーケムキャト社製)を担持する触媒2gからなる層
12を設けた。
[Embodiment 2] The suction type carbon monoxide concentration measuring device B has been described above. Next, a diffusion type carbon monoxide concentration measuring device C which is another embodiment of the present invention will be described. The figure is shown in FIG. That is, the same two sensor elements as those used as the sensor element A'in Example 1 (each A '
α and A′β are bottomed cylinders (column 11 respectively)
α and the column 11β) were installed at the bottom of the column, and two columns were prepared by filling the mouth side of the column with 5 g of granular soda lime. Next, a layer 12 composed of 2 g of a catalyst carrying a platinum-based oxidation catalyst (manufactured by Nchemchem Co.) for oxidizing and burning carbon monoxide and hydrogen gas at room temperature was provided at the opening of the column 11β.

【0023】このような構成により、実施例1の測定器
Bにおけるセンサ素子Aと同様にセンサ素子A’αは試
料ガスの一酸化炭素成分に対してのみ感度を有するよう
になる。一方センサA’βは、一酸化炭素成分も上記触
媒層12によって二酸化炭素に転換された後、ソーダ石
灰によって除去されてしまうため、補償センサ素子とし
て働く。
With such a configuration, the sensor element A'α has sensitivity only to the carbon monoxide component of the sample gas, like the sensor element A in the measuring instrument B of the first embodiment. On the other hand, the sensor A′β functions as a compensation sensor element because the carbon monoxide component is also converted into carbon dioxide by the catalyst layer 12 and then removed by soda lime.

【0024】これらセンサ素子A’α及びセンサ素子
A’βの出力をそれぞれインピーダンス変換器13α及
び13βによってインピーダンスに変換し、インピーダ
ンスが等しい抵抗R1及びR2、及び可変抵抗Rvとと
もにブリッジ回路を形成し、拡散式一酸化炭素濃度測定
器Cを形成した。
The outputs of the sensor element A'α and the sensor element A'β are converted into impedances by impedance converters 13α and 13β, respectively, to form a bridge circuit together with resistors R1 and R2 having the same impedance and a variable resistor Rv. A diffusion type carbon monoxide concentration measuring device C was formed.

【0025】この測定器は図6のようにブリッジ回路を
形成したため、試料気体の二酸化炭素濃度が100〜2
000ppm間で変動しても、その出力に及ぼす影響は
2〜4mV程度の小さいものとなり、測定器C全体はS
/N比の非常に高い優れた一酸化炭素濃度センサとな
る。なお、この測定器Cの一酸化炭素濃度に対する出力
特性を図7に示す。
Since this measuring instrument has a bridge circuit as shown in FIG. 6, the carbon dioxide concentration of the sample gas is 100 to 2
Even if it fluctuates within the range of 000 ppm, the effect on the output is as small as about 2 to 4 mV, and the measuring instrument C as a whole has S
It becomes an excellent carbon monoxide concentration sensor having a very high / N ratio. The output characteristics of the measuring instrument C with respect to the carbon monoxide concentration are shown in FIG.

【0026】[0026]

【発明の効果】本発明に係る一酸化炭素濃度測定方法
は、その特有の構成により、目的成分である一酸化炭素
以外のガス濃度の影響が非常に少なく、また、特に低濃
度での感度に優れた測定方法である。
EFFECT OF THE INVENTION The carbon monoxide concentration measuring method according to the present invention has, due to its unique constitution, very little influence of the gas concentration other than the target component, carbon monoxide, and the sensitivity especially at low concentrations. This is an excellent measurement method.

【図面の簡単な説明】[Brief description of the drawings]

【図1】固体電解質型二酸化炭素濃度センサ素子Aの断
面図である。
FIG. 1 is a cross-sectional view of a solid electrolyte type carbon dioxide concentration sensor element A.

【図2】センサ素子Aの二酸化炭素濃度に対する出力特
性を示す図である。
FIG. 2 is a diagram showing an output characteristic of sensor element A with respect to carbon dioxide concentration.

【図3】センサ素子A’の断面図である。FIG. 3 is a sectional view of a sensor element A ′.

【図4】吸引式一酸化炭素濃測定器Bを示す図である。FIG. 4 is a view showing a suction type carbon monoxide concentration measuring device B.

【図5】測定器Bの一酸化炭素濃度に対する出力特性を
示す図である。
FIG. 5 is a diagram showing an output characteristic of measuring instrument B with respect to a carbon monoxide concentration.

【図6】拡散式一酸化濃度測定器Cを示す図である。FIG. 6 is a view showing a diffusion type monoxide concentration measuring device C.

【図7】測定器Cの一酸化炭素濃度に対する出力特性を
示す図である。
FIG. 7 is a diagram showing an output characteristic with respect to a carbon monoxide concentration of a measuring device C.

【図8】従来技術に係る一酸化炭素濃度測定器における
一酸化炭素センサ素子の断面図である。
FIG. 8 is a sectional view of a carbon monoxide sensor element in a carbon monoxide concentration measuring device according to a conventional technique.

【符号の説明】[Explanation of symbols]

1 NASICON層 2a、2b ガス透過性電極 3 触媒層 4 混合炭酸塩からなる層 5 固定材 6 ヒーター 7 基板 8 ソーダ石灰フィルター 9 吸引チェンバー 10 吸引ポンプ 11α、11β カラム 12 触媒層 13α、13β インピーダンス変換器 A 固体電解質型二酸化炭素濃度センサ素子 A’、A’α、A’β センサ素子Aの周囲に触媒層を
コーティングしたもの B 吸引式一酸化炭素濃度測定器 C 拡散式一酸化炭素濃度測定器
1 NASICON layer 2a, 2b Gas permeable electrode 3 Catalyst layer 4 Layer composed of mixed carbonate 5 Fixing material 6 Heater 7 Substrate 8 Soda lime filter 9 Suction chamber 10 Suction pump 11α, 11β Column 12 Catalyst layer 13α, 13β Impedance converter A solid electrolyte type carbon dioxide concentration sensor element A ′, A′α, A′β sensor element A coated with a catalyst layer B suction type carbon monoxide concentration measuring instrument C diffusion type carbon monoxide concentration measuring instrument

Claims (6)

【特許請求の範囲】[Claims] 【請求項1】 試料ガスから二酸化炭素を除去した後、
該ガス中の一酸化炭素を二酸化炭素に転換し、次いで転
換された二酸化炭素の濃度を測定することにより一酸化
炭素濃度を検知することを特徴とする一酸化炭素濃度測
定方法。
1. After removing carbon dioxide from the sample gas,
A carbon monoxide concentration measuring method comprising detecting carbon monoxide concentration by converting carbon monoxide in the gas into carbon dioxide and then measuring the concentration of the converted carbon dioxide.
【請求項2】 一酸化炭素を二酸化炭素に変換する際に
触媒酸化法を用いることを特徴とする請求項1に記載の
一酸化炭素濃度測定方法。
2. The carbon monoxide concentration measuring method according to claim 1, wherein a catalytic oxidation method is used when converting carbon monoxide into carbon dioxide.
【請求項3】 二酸化炭素濃度測定を固体電解質型二酸
化炭素濃度センサによって行うことを特徴とする請求項
1または請求項2に記載の二酸化炭素濃度測定方法。
3. The carbon dioxide concentration measuring method according to claim 1 or 2, wherein the carbon dioxide concentration is measured by a solid electrolyte type carbon dioxide concentration sensor.
【請求項4】 試料ガスから二酸化炭素を除去する二酸
化炭素除去手段、 該ガス中の一酸化炭素を二酸化炭素に転換する一酸化炭
素−二酸化炭素転換手段、及び、 二酸化炭素濃度を測定する二酸化炭素濃度測定手段とを
有することを特徴とする一酸化炭素濃度測定器。
4. A carbon dioxide removing means for removing carbon dioxide from a sample gas, a carbon monoxide-carbon dioxide converting means for converting carbon monoxide in the gas to carbon dioxide, and carbon dioxide for measuring a carbon dioxide concentration. A carbon monoxide concentration measuring instrument comprising: a concentration measuring means.
【請求項5】 上記一酸化炭素−二酸化炭素転換手段が
酸化触媒を用いるものであることを特徴とする請求項4
に記載の一酸化炭素濃度測定器。
5. The carbon monoxide-carbon dioxide conversion means uses an oxidation catalyst.
The carbon monoxide concentration measuring device according to 1.
【請求項6】 上記二酸化炭素濃度測定手段が固体電解
質型二酸化炭素濃度センサであることを特徴とする請求
項4または請求項5に記載の一酸化炭素濃度測定器。
6. The carbon monoxide concentration measuring device according to claim 4, wherein the carbon dioxide concentration measuring means is a solid electrolyte type carbon dioxide concentration sensor.
JP07259728A 1995-10-06 1995-10-06 Carbon monoxide concentration measuring method and measuring instrument Expired - Fee Related JP3139672B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP07259728A JP3139672B2 (en) 1995-10-06 1995-10-06 Carbon monoxide concentration measuring method and measuring instrument

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP07259728A JP3139672B2 (en) 1995-10-06 1995-10-06 Carbon monoxide concentration measuring method and measuring instrument

Publications (2)

Publication Number Publication Date
JPH09101284A true JPH09101284A (en) 1997-04-15
JP3139672B2 JP3139672B2 (en) 2001-03-05

Family

ID=17338125

Family Applications (1)

Application Number Title Priority Date Filing Date
JP07259728A Expired - Fee Related JP3139672B2 (en) 1995-10-06 1995-10-06 Carbon monoxide concentration measuring method and measuring instrument

Country Status (1)

Country Link
JP (1) JP3139672B2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101027824B1 (en) * 2008-10-10 2011-04-07 재단법인 포항산업과학연구원 A dual mode control method for a combustion system using a additional CO concentration
WO2015002060A1 (en) * 2013-07-02 2015-01-08 国立大学法人長崎大学 Co sensor and method for manufacturing co sensor
JPWO2021250970A1 (en) * 2020-06-12 2021-12-16

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101027824B1 (en) * 2008-10-10 2011-04-07 재단법인 포항산업과학연구원 A dual mode control method for a combustion system using a additional CO concentration
WO2015002060A1 (en) * 2013-07-02 2015-01-08 国立大学法人長崎大学 Co sensor and method for manufacturing co sensor
JPWO2015002060A1 (en) * 2013-07-02 2017-02-23 国立大学法人 長崎大学 CO sensor and method of manufacturing CO sensor
JPWO2021250970A1 (en) * 2020-06-12 2021-12-16
WO2021250970A1 (en) * 2020-06-12 2021-12-16 トライポッド・デザイン株式会社 Sensor

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