JPH057567Y2 - - Google Patents
Info
- Publication number
- JPH057567Y2 JPH057567Y2 JP12469386U JP12469386U JPH057567Y2 JP H057567 Y2 JPH057567 Y2 JP H057567Y2 JP 12469386 U JP12469386 U JP 12469386U JP 12469386 U JP12469386 U JP 12469386U JP H057567 Y2 JPH057567 Y2 JP H057567Y2
- Authority
- JP
- Japan
- Prior art keywords
- flow rate
- gas
- rate control
- reaction tank
- sample gas
- 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.)
- Expired - Lifetime
Links
- 238000005259 measurement Methods 0.000 claims description 22
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 claims description 19
- 238000004020 luminiscence type Methods 0.000 claims description 4
- 239000007789 gas Substances 0.000 description 83
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- MGWGWNFMUOTEHG-UHFFFAOYSA-N 4-(3,5-dimethylphenyl)-1,3-thiazol-2-amine Chemical compound CC1=CC(C)=CC(C=2N=C(N)SC=2)=C1 MGWGWNFMUOTEHG-UHFFFAOYSA-N 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
Description
【考案の詳細な説明】
〔産業上の利用分野〕
この考案は公害防止機器などに付設されて、排
気ガス中に含まれるアンモニアガス、二酸化窒素
ガス、一酸化窒素ガス等を測定するために使用す
る化学発光式分析計に関する。[Detailed description of the invention] [Industrial application field] This invention is attached to pollution prevention equipment and used to measure ammonia gas, nitrogen dioxide gas, nitrogen monoxide gas, etc. contained in exhaust gas. Regarding a chemiluminescent analyzer.
一般にケミルミ法と呼ばれ一酸化窒素ガス
（NOガス）がオゾンガス（O3ガス）と反応する
ときに発する光の強度を光電子増倍管等の検出器
で検出する方法を利用した化学発光式分析計は、
試料ガスを一定の流量に制御する流量制御部と、
オゾンガスを供給するオゾン発生器と、前記流量
制御部から導入される試料ガス中のNOガスに前
記オゾン発生器から導入されるオゾンガスを反応
させて化学発光させる反応槽と、この反応槽での
化学発光の発光量を検出する検出器と、この検出
器からの検出信号に基づいて測定ガス濃度を演算
表示する表示部とから構成されている。このよう
に構成された分析計においては、反応槽へ導入さ
れる定量の試料ガス中のNOガス濃度に応じて発
光量は変化し、この発光量がある範囲を超えると
きには、濃度に対応して設定された測定レンジの
いずれかに切り換えることにより行なつている。
Chemiluminescence analysis, which is generally called the chemiluminescence method, uses a method that uses a detector such as a photomultiplier tube to detect the intensity of the light emitted when nitrogen monoxide gas (NO gas) reacts with ozone gas (O 3 gas). The total is
a flow rate control unit that controls the sample gas to a constant flow rate;
an ozone generator that supplies ozone gas; a reaction tank that causes chemiluminescence by causing the ozone gas introduced from the ozone generator to react with the NO gas in the sample gas introduced from the flow rate controller; It consists of a detector that detects the amount of emitted light and a display section that calculates and displays the measured gas concentration based on the detection signal from the detector. In an analyzer configured in this way, the amount of luminescence changes depending on the NO gas concentration in the fixed amount of sample gas introduced into the reaction tank, and when this amount of luminescence exceeds a certain range, it changes depending on the concentration. This is done by switching to one of the set measurement ranges.
ところで、NOガスとオゾンガスとの反応によ
る化学発光量は、一定のオゾンガスの量に対し
NOガスの量が少ない場合には近似直線的に変化
するに対し、NOガス量が増大するにつれて直線
性が悪くなり、場合によつてはオゾンガスが不足
して測定できない場合が生じる。このことから、
試料ガスを一定流量に制御する一つの流量制御部
を備えた従来の分析計では、直線性の良い範囲で
化学発光させるには、前記流量制御部の試料ガス
を、所定濃度に対応した流量に設定しなければな
らず、従つて、測定できる濃度の範囲は、測定レ
ンジの切換を行なつても限定された狭いものとな
る点に問題があつた。
By the way, the amount of chemiluminescence due to the reaction between NO gas and ozone gas is
When the amount of NO gas is small, it changes approximately linearly, but as the amount of NO gas increases, the linearity worsens, and in some cases, ozone gas may be insufficient and measurement cannot be performed. From this,
In conventional analyzers equipped with one flow rate controller that controls the sample gas at a constant flow rate, in order to generate chemiluminescence within a range with good linearity, the sample gas in the flow rate controller must be adjusted to a flow rate corresponding to a predetermined concentration. Therefore, there was a problem in that the measurable concentration range was limited and narrow even if the measurement range was switched.
この考案は上記問題点を解消し、低濃度から高
濃度までの幅の広い測定レンジを性能良く測定で
きる化学発光式分析計を提供することを課題とし
ている。 The object of this invention is to solve the above-mentioned problems and provide a chemiluminescent analyzer that can measure a wide measurement range from low to high concentrations with good performance.
この考案は上記課題を達成するため化学発光式
分析計を以下のような構成とした。
In order to achieve the above-mentioned problems, this invention uses a chemiluminescent analyzer with the following configuration.
すなわち、ガス流量を一定にして制御する流量
制御部と、この流量制御部を通して導入される導
入ガス中のNOガスと別途供給されるオゾンガス
とを反応させて化学発光させる反応槽と、この反
応槽における発光量を検出する検出器とを備えて
なる化学発光式分析計において、ガス流量を一定
にして制御する流量制御部を、それぞれ制御する
ガス流量を異ならせて複数並設するとともに、こ
れら流量制御部を導入ガス中のNOガスの濃度に
応じて択一的に前記反応槽へ流路連絡する流路切
換え手段を設け、かつ前記各流量制御部にそれぞ
れ対応してフルスケール時の測定濃度値がそれぞ
れ異なつた測定レンジを複数設けたことを特徴と
する化学発光式分析計を要旨としている。 In other words, a flow rate control unit that controls the gas flow rate at a constant level, a reaction tank that causes chemiluminescence by reacting NO gas in the introduced gas introduced through the flow rate control unit with ozone gas that is supplied separately, and this reaction tank. In a chemiluminescence analyzer, a plurality of flow rate control units are arranged in parallel to control a constant gas flow rate, each controlling a different gas flow rate. A flow path switching means is provided to selectively connect the control section to the reaction tank depending on the concentration of NO gas in the introduced gas, and the measured concentration at full scale is provided in correspondence with each of the flow rate control sections. The gist of this paper is a chemiluminescent analyzer that is characterized by having multiple measurement ranges with different values.
以上のような構成としたこの考案に係る化学発
光式分析計は、試料ガス中に含まれるNOガスの
濃度に応じて、それぞれ一定に制御する流量が異
なる複数の流量制御部のいずれかを通る流路に切
り換えることにより、濃度に応じて設けたフルス
ケールの測定レンジに切換えられるとともに、流
量制御部を通して導入される試料ガスの流量とそ
の試料ガス中のNOガス濃度とによつて定まる
NOガスの量とオゾン発生器から導入されるオゾ
ンガスの量との比を、化学発光量の直線的変化の
範囲とすることができ、各測定レンジでの発光量
が同一レベルとなる。すなわち、反応槽に導入さ
れる試料ガス中のNOガス濃度が高くなると、反
応槽に導入する試料ガスの流量を少なくし、試料
ガス中のNOガス濃度が低くなると、反応槽に導
入する試料ガスの流量を多くすることにより、
NOガス量とオゾンガス量との比を、NOガス濃
度と化学発光量との間の近似直線性が得られる範
囲とし、また、それに対応して測定レンジの切換
えが行なわれるのである。
The chemiluminescence analyzer according to this invention configured as described above has a sample gas that passes through one of multiple flow rate control units each controlling a constant flow rate depending on the concentration of NO gas contained in the sample gas. By switching to the flow path, the measurement range is switched to a full-scale measurement range that is set according to the concentration, and is determined by the flow rate of the sample gas introduced through the flow rate controller and the NO gas concentration in the sample gas.
The ratio between the amount of NO gas and the amount of ozone gas introduced from the ozone generator can be set within a range where the amount of chemiluminescence changes linearly, so that the amount of luminescence in each measurement range is at the same level. In other words, when the concentration of NO gas in the sample gas introduced into the reaction tank increases, the flow rate of the sample gas introduced into the reaction tank is reduced, and when the concentration of NO gas in the sample gas becomes low, the flow rate of the sample gas introduced into the reaction tank is reduced. By increasing the flow rate of
The ratio between the amount of NO gas and the amount of ozone gas is set in a range that provides approximate linearity between the NO gas concentration and the amount of chemiluminescence, and the measurement range is switched accordingly.
次にこの考案に係る化学発光式分析計の１実施
例を図を参照しながら説明する。
Next, one embodiment of the chemiluminescent analyzer according to this invention will be described with reference to the drawings.
図は３つの流量制御部を並列に配管した場合で
ある。すなわち、試料ガス流路系は、反応槽１
に、オゾン発生器２から一定量のオゾンガスを導
入するためのオゾン流路３と試料ガス入口４から
導入された試料ガスを流量制御部を介して導入す
る試料ガス流路５及び反応後のガスを排気するた
めの排気路６がそれぞれ配管され、前記試料ガス
入口４と前記試料ガス流路５との間には、測定ガ
ス濃度に対応する異なる流量にそれぞれ制御され
た第１流量制御部７、第２流量制御部８、第３流
量制御部９を並列に配管接続するとともに、第２
流量制御部８と第３流量制御部９のそれぞれに流
出側と試料ガス流路５との間に切換え弁１０，１
１を設けた流量制御部１２が配管接続された構成
となつている。また、検出系は、発生槽１内での
試料ガス中の測定ガスとオゾンガスとの反応によ
る化学発光の光強度を検出する光検出器１３を反
応槽１に設け、この光検出器１３において検出さ
れた測定信号をアンプ１４を介して表示部１５に
送るように電気的に接続された構成となつてい
る。また、３つの切換接点Ａ，Ｂ，Ｃと電源に接
続された共通接点とを有し、切換接点Ｂ，Ｃがそ
れぞれ切換え弁１０，１１に接続された測定レン
ジ切換え器１６が設けられている。この測定レン
ジ切換え器１６を切換え操作して、電源を切換接
点Ａに接続させると、切換え弁１０，１１は動作
せずに、試料ガスが第１流量制御部７を通して反
応槽１に導入され、電源を切換接点Ｂに接続させ
ると、切換え弁１０が動作し、試料ガスは第２流
量制御部８を通して反応槽１に導入され、また、
電源を切換接点Ｃに接続させると、切換え弁１１
が動作し、試料ガスは第３流量制御部９を通して
反応槽１に導入されることになる。そして、アン
プ１４には、測定レンジ切換え器１６の切換え操
作に連動するスパン調整器１７が設けられてお
り、このスパン調整器１７の切換え動作により、
各流量制御部７，８，９にそれぞれ対応してフル
スケール時の測定濃度値がそれぞれ異なつた３つ
の測定レンジのうちの何れかに切り換わる構成と
なつている。例えば、第１流量制御部７、第２流
量制御部８、第３流量制御部９の流量比を１：
10：20に設定した場合に、測定レンジＡのフルス
ケール時における測定濃度値を例えば1000ppmと
すれば、測定レンジＢ，Ｃのフルスケール時にお
ける測定濃度値はそれぞれ100ppm、50ppmとな
る。 The figure shows a case where three flow rate control units are piped in parallel. In other words, the sample gas flow path system
, an ozone flow path 3 for introducing a certain amount of ozone gas from the ozone generator 2, a sample gas flow path 5 for introducing the sample gas introduced from the sample gas inlet 4 via a flow rate controller, and a gas after reaction. A first flow rate controller 7 is provided between the sample gas inlet 4 and the sample gas flow path 5, each of which is controlled to a different flow rate corresponding to the measurement gas concentration. , the second flow rate control section 8, and the third flow rate control section 9 are connected by piping in parallel, and the second flow rate control section 8 and the third flow rate control section 9 are
Switching valves 10 and 1 are provided between the outflow side and the sample gas channel 5 in each of the flow rate control unit 8 and the third flow rate control unit 9.
1 is connected to the flow rate control section 12 via piping. In addition, the detection system is provided with a photodetector 13 in the reaction tank 1 that detects the light intensity of chemiluminescence caused by the reaction between the measurement gas in the sample gas and ozone gas in the generation tank 1. The display unit 15 is electrically connected to send the measured signal to the display unit 15 via the amplifier 14. Further, a measurement range switch 16 is provided, which has three switching contacts A, B, and C and a common contact connected to a power source, and the switching contacts B and C are connected to switching valves 10 and 11, respectively. . When the measurement range switch 16 is operated to connect the power source to the switching contact A, the sample gas is introduced into the reaction tank 1 through the first flow rate controller 7 without operating the switching valves 10 and 11. When the power source is connected to the switching contact B, the switching valve 10 is operated, and the sample gas is introduced into the reaction tank 1 through the second flow rate controller 8, and
When the power source is connected to the switching contact C, the switching valve 11
is operated, and the sample gas is introduced into the reaction tank 1 through the third flow rate controller 9. The amplifier 14 is provided with a span adjuster 17 that is linked to the switching operation of the measurement range switch 16, and the switching operation of the span regulator 17 causes
The configuration is such that the measured concentration value at full scale is switched to one of three measurement ranges corresponding to each flow rate control section 7, 8, and 9, each having a different value. For example, the flow rate ratio of the first flow rate control section 7, the second flow rate control section 8, and the third flow rate control section 9 is set to 1:
If the measurement range A is set to 10:20 and the measured concentration value at full scale is, for example, 1000 ppm, then the measured concentration values at full scale in measurement ranges B and C are 100 ppm and 50 ppm, respectively.
上記した実施例に係る化学発光式分析系におい
ては、切換え弁１０，１１によつて第２、第３流
量制御部８，９の流路を閉塞した状態では試料ガ
スは第１流量制御部７から試料ガス流路５を通つ
て反応槽１に導かれる。そして、切換え弁１０を
開とすると、第１流量制御部７の流出側が閉塞さ
れて試料ガスは第２流量制御部８から試料ガス流
路５を通つて反応槽１に導入される。この場合、
例えば、第１流量制御部７、第２流量制御部８、
第３流量制御部９の流量の比率を１：10：20に制
御すると、試料ガス中のNOガスの濃度が例えば
1000ppmであるときは、試料ガスが第１流量制御
部７を通して反応槽１に導入されるように切換え
弁１０，１１を設定し、試料ガス中のNOガスの
濃度が100ppmであるときは、試料ガスが第２流
量制御部８を、NOガスの濃度が50ppmであると
きは、試料ガスが第３流量制御部９をそれぞれ通
して反応槽１に導入されるように切換え弁１０，
１１を切換え設定する。このように流路を切換え
弁１０，１１によつて切換えることにより、各流
量制御部に対応する測定レンジの切換えが行なわ
れ、各測定レンジにおける反応槽１内の化学発光
量を同一レベルとすることができるようになる。 In the chemiluminescent analysis system according to the embodiment described above, when the flow paths of the second and third flow rate controllers 8 and 9 are closed by the switching valves 10 and 11, the sample gas is transferred to the first flow rate controller 7. The sample gas is introduced into the reaction tank 1 through the sample gas flow path 5. When the switching valve 10 is opened, the outflow side of the first flow rate control section 7 is closed, and the sample gas is introduced from the second flow rate control section 8 into the reaction tank 1 through the sample gas channel 5. in this case,
For example, the first flow rate control section 7, the second flow rate control section 8,
If the flow rate ratio of the third flow rate controller 9 is controlled to 1:10:20, the concentration of NO gas in the sample gas will be
When the concentration of NO gas in the sample gas is 1000 ppm, the switching valves 10 and 11 are set so that the sample gas is introduced into the reaction tank 1 through the first flow rate controller 7, and when the concentration of NO gas in the sample gas is 100 ppm, the sample gas The switching valve 10 is configured so that the gas is introduced into the reaction tank 1 through the second flow rate control unit 8, and when the concentration of NO gas is 50 ppm, the sample gas is introduced into the reaction tank 1 through the third flow rate control unit 9.
11 and set it. By switching the flow paths using the switching valves 10 and 11 in this manner, the measurement range corresponding to each flow rate control section is switched, and the amount of chemiluminescence in the reaction tank 1 in each measurement range is made to be at the same level. You will be able to do this.
なお、上記実施例では、三つの流量制御部を並
列に配設してその流量を制御する場合について説
明したが、その数は限定されるものでないことは
いうまでもない。また流量制御部の流路の切換え
による測定レンジの切換えとは別に、手動もしく
は自動切換えのできる切換レンジを設ける場合も
ある。 In the above embodiment, a case has been described in which three flow rate control units are arranged in parallel to control the flow rate, but it goes without saying that the number is not limited. In addition to switching the measurement range by switching the flow path of the flow rate controller, a switching range that can be switched manually or automatically may be provided.
この考案に係る化学発光式分析計によれば、異
なる流量に制御される複数の流量制御部を並列し
て設けてこの流路を切換えることにより、濃度に
対応したレンジに切換える構成としたから、各レ
ンジにおいて、反応槽へ流入するNOガスの量と
オゾンガスの量との比が化学発光量の直線的変化
の範囲となり、その発光量は同一レベルとなるこ
とから、低濃度から高濃度まで幅の広いレンジを
性能よく安定した測定ができる化学発光式分析計
が提供し得たのである。
According to the chemiluminescent analyzer according to this invention, a plurality of flow rate controllers controlled at different flow rates are provided in parallel and the flow paths are switched to switch to a range corresponding to the concentration. In each range, the ratio between the amount of NO gas flowing into the reaction tank and the amount of ozone gas is the range in which the amount of chemiluminescence changes linearly, and the amount of emitted light is at the same level, so there is a wide range from low concentration to high concentration. This enabled us to provide a chemiluminescent analyzer that can perform stable measurements over a wide range of conditions.
図はこの考案に係る化学発光式分析計の１実施
例の概略構成図ある。
１……反応槽、２……オゾン発生器、３……オ
ゾン流路、４……試料ガス入口、５……試料ガス
流路、６……排気路、７……第１流量制御部、８
……第２流量制御部、９……第３流量制御部、１
０，１１……切換え弁、１２……流量制御部、１
３……光検出器、１４……アンプ、１５……表示
部。
The figure is a schematic diagram of one embodiment of the chemiluminescent analyzer according to this invention. DESCRIPTION OF SYMBOLS 1... Reaction tank, 2... Ozone generator, 3... Ozone flow path, 4... Sample gas inlet, 5... Sample gas flow path, 6... Exhaust path, 7... First flow rate control section, 8
...Second flow rate control section, 9...Third flow rate control section, 1
0, 11...Switching valve, 12...Flow rate control section, 1
3...Photodetector, 14...Amplifier, 15...Display unit.
Claims (1)
この流量制御部を通して導入される導入ガス中の
NOガスと別途供給されるオゾンガスとを反応さ
せて化学発光させる反応槽と、この反応槽におけ
る発光量を検出する検出器とを備えてなる化学発
光式分析計において、ガス流量を一定にして制御
する流量制御部を、それぞれ制御するガス流量を
異ならせて複数並設するとともに、これら流量制
御部を導入ガス中のNOガスの濃度に応じて択一
的に前記反応槽へ流路連絡する流路切換え手段を
設け、かつ前記各流量制御部にそれぞれ対応して
フルスケール時の測定濃度値がそれぞれ異なつた
測定レンジを複数設けたことを特徴とする化学発
光式分析計。 a flow rate control unit that controls a constant gas flow rate;
In the introduced gas introduced through this flow rate control section,
In a chemiluminescent analyzer that is equipped with a reaction tank that reacts NO gas and ozone gas supplied separately to produce chemiluminescence, and a detector that detects the amount of luminescence in this reaction tank, the gas flow rate is kept constant and controlled. A plurality of flow rate control units are arranged in parallel, each controlling a different gas flow rate, and these flow rate control units are connected to a flow path that selectively connects to the reaction tank depending on the concentration of NO gas in the introduced gas. A chemiluminescent analyzer characterized in that a chemiluminescent analyzer is provided with a path switching means, and a plurality of measurement ranges each having a different measured concentration value at full scale are provided corresponding to each of the flow rate control sections.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12469386U JPH057567Y2 (en) | 1986-08-13 | 1986-08-13 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12469386U JPH057567Y2 (en) | 1986-08-13 | 1986-08-13 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6331359U JPS6331359U (en) | 1988-02-29 |
| JPH057567Y2 true JPH057567Y2 (en) | 1993-02-25 |
Family
ID=31016944
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12469386U Expired - Lifetime JPH057567Y2 (en) | 1986-08-13 | 1986-08-13 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH057567Y2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0635165Y2 (en) * | 1988-05-24 | 1994-09-14 | 株式会社堀場製作所 | Chemiluminescent gas analyzer for measuring multiple samples |
| JPH07111399B2 (en) * | 1991-02-19 | 1995-11-29 | 株式会社島津製作所 | Chemiluminescence type nitrogen oxide measuring device |
-
1986
- 1986-08-13 JP JP12469386U patent/JPH057567Y2/ja not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6331359U (en) | 1988-02-29 |
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