JPH0421811B2 - - Google Patents
Info
- Publication number
- JPH0421811B2 JPH0421811B2 JP58036908A JP3690883A JPH0421811B2 JP H0421811 B2 JPH0421811 B2 JP H0421811B2 JP 58036908 A JP58036908 A JP 58036908A JP 3690883 A JP3690883 A JP 3690883A JP H0421811 B2 JPH0421811 B2 JP H0421811B2
- Authority
- JP
- Japan
- Prior art keywords
- exhaust gas
- introduction pipe
- filter
- gas introduction
- particulates
- 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
- 239000007789 gas Substances 0.000 claims description 75
- 238000010438 heat treatment Methods 0.000 claims description 15
- 239000007787 solid Substances 0.000 claims description 15
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 14
- 239000001257 hydrogen Substances 0.000 claims description 14
- 229910052739 hydrogen Inorganic materials 0.000 claims description 14
- 229930195733 hydrocarbon Natural products 0.000 claims description 12
- 150000002430 hydrocarbons Chemical class 0.000 claims description 12
- 239000007788 liquid Substances 0.000 claims description 11
- 238000001514 detection method Methods 0.000 claims description 6
- 239000002245 particle Substances 0.000 description 16
- 238000010790 dilution Methods 0.000 description 3
- 239000012895 dilution Substances 0.000 description 3
- 239000004215 Carbon black (E152) Substances 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000002123 temporal effect Effects 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000004071 soot Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
- G01N15/0606—Investigating concentration of particle suspensions by collecting particles on a support
- G01N15/0618—Investigating concentration of particle suspensions by collecting particles on a support of the filter type
Landscapes
- Chemical & Material Sciences (AREA)
- Dispersion Chemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は、排気ガス中の微粒子の測定装置に
係り、特にデイゼール機関排気ガス中の微粒子中
の固体微粒子および液状微粒子の測定に好適な測
定装置に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an apparatus for measuring particulates in exhaust gas, and is particularly suitable for measuring solid particulates and liquid particulates in particulates in diesel engine exhaust gas. Regarding equipment.
従来の排気ガスの微粒子測定方法には、排気ガ
スを希釈トンネル内に導き空気希釈した後にろ紙
でろ過し、ろ紙に付着した微粒子を測定する希釈
トンネル法（例えば、特開昭56−118641号公報参
照）があり、さらに、先願として本発明者が考案
した、排気ガスを加熱オーブン内に導きすべての
炭化水素を気化させ、ろ紙で固体微粒子をろ過し
た後、排気ガスを加熱型水素炎イオン化検出器に
導き炭化水素の量、すなわち、液状微粒子の量を
測定する装置（実開昭58−134767号公報）があ
る。しかし、希釈トンネル法は操作が熕雑で連続
測定ができず、かつ、固体微粒子の測定はできる
が液状微粒子の検出ができない。また、炭化水素
検出法では、液状微粒子を測定できるが、固体微
粒子は測定できない。これら従来の方法では、排
気ガス中の固体微粒子と液状微粒子とを区別して
測定できないという問題があつた。
Conventional methods for measuring particulates in exhaust gas include the dilution tunnel method, in which exhaust gas is guided into a dilution tunnel, diluted with air, filtered with filter paper, and particulates adhering to the filter paper are measured (e.g., JP-A-56-118641). In addition, the inventor devised a prior application in which the exhaust gas is guided into a heating oven to vaporize all the hydrocarbons, and after filtering solid particles with filter paper, the exhaust gas is subjected to heated hydrogen flame ionization. There is a device (Japanese Utility Model Application Publication No. 134767/1983) that measures the amount of hydrocarbons, that is, the amount of liquid fine particles, by introducing them into a detector. However, the dilution tunnel method is complicated to operate and cannot be used for continuous measurement, and although solid particles can be measured, liquid particles cannot be detected. Furthermore, in the hydrocarbon detection method, liquid particles can be measured, but solid particles cannot be measured. These conventional methods have a problem in that solid particles and liquid particles in exhaust gas cannot be measured separately.
この発明は、このような従来の問題点を解消す
べく創案されたもので、排気ガス中の固体微粒子
および液状微粒子の測定を区別して連続的かつ高
精度に行い得る測定装置を提供することを目的と
する。 This invention was devised to solve these conventional problems, and aims to provide a measuring device that can distinguish between solid particulates and liquid particulates in exhaust gas and carry out continuous and highly accurate measurements. purpose.
上記の目的を達成するために、本発明の排気ガ
ス中の微粒子の測定装置は、排気ガス導入管内で
排気ガスのすべての炭化水素が気化する温度まで
加熱する加熱装置と、この排気ガス導入管の中途
に設けられたフイルタと、このフイルタの前後の
圧力差を検出する差圧計と、排気ガス導入管の終
端に接続された加熱型水素炎イオン化検出器と、
差圧計および加熱型水素炎イオン化検出器の検出
信号の変化に基づいて排気ガス中の固体微粒子お
よび液状微粒子の量を算出する演算器とを備えた
装置である。
In order to achieve the above object, the apparatus for measuring particulates in exhaust gas of the present invention includes a heating device that heats the exhaust gas to a temperature at which all hydrocarbons in the exhaust gas are vaporized in the exhaust gas introduction pipe, and a A filter provided midway, a differential pressure gauge that detects the pressure difference before and after the filter, and a heated hydrogen flame ionization detector connected to the end of the exhaust gas introduction pipe.
This device includes a differential pressure gauge and a calculator that calculates the amount of solid particles and liquid particles in the exhaust gas based on changes in the detection signal of the heated hydrogen flame ionization detector.
〔実施例および作用〕
次にこの発明に係る測定装置の一実施例を図面
に基づいて説明する。[Embodiment and operation] Next, an embodiment of the measuring device according to the present invention will be described based on the drawings.
測定装置は、排気ガスが導入される排気ガス導
入管１を備え、この排気ガス導入管１は、加熱オ
ーブン２を通つて加熱オーブン３内に導入されて
いる。排気ガス導入管１には、加熱オーブン２内
において入口側から順次、電磁弁４、フイルタ
５、流量調節バブル６、試料採取ポンプ７、オリ
フイス８が設けられ、資料採取ポンプ７は、排気
ガス導入管１内に排気ガスＧ１を導入し、流量調
整バルブ６はその流量を調節する。流量調整バル
ブ６は、流量制御装置９によつて制御されるモー
タ１０によつて駆動され、流量制御装置９はオリ
フイス８前後の圧力差１１によつて検出し、その
検出値に基づいて流量調整バルブ６を制御する。
フイルタ５を通過する排気ガスＧ１は、排気ガス
Ｇ１中の全ての炭化水素が気化される温度にまで
加熱オーブン２によつて加熱され、炭化水素は全
く補集されることなくフイルタ５を通過する。従
つて、フイルタ５においてはすすや鉄錆などの固
体微粒子のみが捕集される。排気ガス導入管１に
は、フイルタ５の前後の圧力差を検出する差圧計
１２が接続され、さらに、フイルタ５に流入する
排気ガスＧ１の圧力、温度をそれぞれ検出する圧
力計１３および温度計１４が接続されている。フ
イルタ５は固体微粒子の重量濃度に応じて目詰ま
りが顕著となり、目詰まりの時間的変化、すなわ
ちフイルタ５前後の差圧の時間的変化を検出すれ
ば、固体微粒子の重量濃度を測定することができ
る差圧計１２、圧力形１３、温度計１４および流
量制御装置９は演算器１５に接続され、演算器１
５は圧力計１３、温度計１４の検出信号に基づい
て排気ガスＧ１の密度および粘性係数を算出し、
流量制御装置９の出力信号から得られる排気ガス
Ｇ１の流量、前記密度、粘性係数および差圧計１
２の検出信号に基づいて固体微粒子の重量濃度を
算出する。 The measuring device includes an exhaust gas introduction pipe 1 into which exhaust gas is introduced, and this exhaust gas introduction pipe 1 is introduced into a heating oven 3 through a heating oven 2. The exhaust gas introduction pipe 1 is provided with a solenoid valve 4, a filter 5, a flow rate adjustment bubble 6, a sample collection pump 7, and an orifice 8 in order from the inlet side in the heating oven 2. Exhaust gas G1 is introduced into the pipe 1, and the flow rate regulating valve 6 regulates its flow rate. The flow rate adjustment valve 6 is driven by a motor 10 controlled by a flow rate control device 9, which detects the pressure difference 11 across the orifice 8 and adjusts the flow rate based on the detected value. Control valve 6.
The exhaust gas G1 passing through the filter 5 is heated by the heating oven 2 to a temperature at which all the hydrocarbons in the exhaust gas G1 are vaporized, and the exhaust gas G1 passes through the filter 5 without being collected at all. . Therefore, the filter 5 collects only solid particles such as soot and iron rust. A differential pressure gauge 12 that detects the pressure difference before and after the filter 5 is connected to the exhaust gas introduction pipe 1, and a pressure gauge 13 and a thermometer 14 that detect the pressure and temperature of the exhaust gas G1 flowing into the filter 5, respectively. is connected. The filter 5 becomes noticeably clogged depending on the weight concentration of the solid particles, and by detecting the temporal change in clogging, that is, the temporal change in the differential pressure before and after the filter 5, the weight concentration of the solid particles can be measured. The differential pressure gauge 12, pressure type 13, thermometer 14, and flow rate control device 9 that can be connected to the computing unit 15 are connected to the computing unit 15.
5 calculates the density and viscosity coefficient of the exhaust gas G1 based on the detection signals of the pressure gauge 13 and the thermometer 14;
The flow rate of the exhaust gas G1 obtained from the output signal of the flow rate control device 9, the density, the viscosity coefficient, and the differential pressure gauge 1
The weight concentration of the solid fine particles is calculated based on the detection signal of step 2.
ここに、固体微粒子の重量濃度をＣ、フイルタ
５前後の差圧力を△Ｐ、時間をｔ、排気ガスＧ１
の温度、圧力をＴ、Ｐ、排気ガスＧ１の粘性係数
をμ、基準状態（温度T0、圧力P0）における排
気ガスＧ１の粘性係数をμ0、基準状態に換算した
排気ガスＧ１の流量をQ0、常数をＫとするとき、
Ｃ＝Ｋ・（μ0／μ）・（T0／Ｔ）・（Ｐ／P0）・
（１／Q0）・ｄ（△Ｐ）／dt
となる。 Here, the weight concentration of solid particles is C, the differential pressure before and after the filter 5 is △P, the time is t, and the exhaust gas G1
The temperature and pressure are T and P, the viscosity coefficient of exhaust gas G1 is μ, the viscosity coefficient of exhaust gas G1 in the reference state (temperature T 0 and pressure P 0 ) is μ 0 , and the flow rate of exhaust gas G1 converted to the reference state is When Q 0 is Q 0 and K is a constant, C=K・(μ 0 /μ)・(T 0 /T)・(P/P 0 )・
(1/Q 0 )・d(△P)/dt.
加熱オーブン３内において、排気ガス導入管１
には、サンプルキヤピラリ１６および加熱型水素
炎イオン化検出器１７が設けられ、フイルタ５で
ろ過された排気ガスＧ１は、サンプルキヤピラリ
１６において流量が均一化された後に加熱型水素
炎イオン化検出器１７で測定される。すなわち、
加熱型水素炎イオン化検出器１７により、排気ガ
スＧ１中の炭化水素濃度を測定し排気ガス中の液
状微粒子の量を知ることができる。 Inside the heating oven 3, the exhaust gas introduction pipe 1
is equipped with a sample capillary 16 and a heated hydrogen flame ionization detector 17, and the exhaust gas G1 filtered by the filter 5 is passed through the heated hydrogen flame ionization detector after the flow rate is equalized in the sample capillary 16. Measured at 17. That is,
The heated hydrogen flame ionization detector 17 measures the concentration of hydrocarbons in the exhaust gas G1, and the amount of liquid particles in the exhaust gas can be determined.
排気ガス導入管１には、加熱オーブン２内で基
準ガス導入管１８が接続され、この基準ガス導入
管１８はゼロガス導入管１９とスパンガス導入管
２０とに分岐している。ゼロガス導入管１９、、
スパンガス導入管２０には、、電磁弁２１，２２
がそれぞれ設けられ、前記電磁弁４とともにこれ
らの電磁弁２１，２２を制御すれば、排気ガス導
入管１には、排気ガスＧ１、、ゼロガスＧ２、ス
パンガスＧ３いずれかを選択的に導入できる。ゼ
ロガスＧ２は全く炭化水素を含まない基準ガスで
あり、スパンガスＧ３は既知の濃度の炭化水素を
含む基準ガスである。加熱型水素炎イオン化検出
器１７は、ゼロガスＧ２導入時にゼロ点校正を行
い、スパンガスＧ３導入時にスパン校正を行う。 A reference gas introduction pipe 18 is connected to the exhaust gas introduction pipe 1 within the heating oven 2, and this reference gas introduction pipe 18 branches into a zero gas introduction pipe 19 and a span gas introduction pipe 20. Zero gas introduction pipe 19,
The span gas introduction pipe 20 includes solenoid valves 21 and 22.
are provided respectively, and by controlling these electromagnetic valves 21 and 22 together with the electromagnetic valve 4, it is possible to selectively introduce exhaust gas G1, zero gas G2, or span gas G3 into exhaust gas introduction pipe 1. Zero gas G2 is a reference gas containing no hydrocarbons, and span gas G3 is a reference gas containing a known concentration of hydrocarbons. The heated hydrogen flame ionization detector 17 performs zero point calibration when zero gas G2 is introduced, and span calibration when span gas G3 is introduced.
排気ガス導入管１には、加熱オーブン２，３間
に追おいて分岐管２３が接続され、この分岐管２
３には、圧力調整器２４が設けられている。圧力
調整器２４は、圧力計２５によつて測定される分
岐管２３内の圧力に応じて作動し、余分な排気ガ
スＧ１を排出して、加熱型水素炎イオン化検出器
１７に過剰の排気ガスＧ１が導入されることを防
止する。分岐管２３にはさらに流量計２６が設け
られ、排出される排気ガスＧ１の流量が測定され
る。 A branch pipe 23 is connected to the exhaust gas introduction pipe 1 between the heating ovens 2 and 3.
3 is provided with a pressure regulator 24. The pressure regulator 24 operates according to the pressure within the branch pipe 23 measured by the pressure gauge 25, and discharges excess exhaust gas G1 to supply the excess exhaust gas to the heated hydrogen flame ionization detector 17. Prevent G1 from being introduced. The branch pipe 23 is further provided with a flow meter 26 to measure the flow rate of the exhaust gas G1 to be discharged.
加熱型水素炎イオン化検出器１７も前記演算器
１５に接続され、演算器は加熱型水素炎イオン化
検出器１７の検出信号に基づいて炭化水素濃度を
算出する。 A heated hydrogen flame ionization detector 17 is also connected to the arithmetic unit 15, and the arithmetic unit calculates the hydrocarbon concentration based on the detection signal of the heated hydrogen flame ionization detector 17.
前述のとおり、この発明に係る排気ガス中の微
粒子の測定装置は、排気ガス導入管内での全ての
炭化水素が気化する温度まで加熱された排気ガス
を、フイルタによつてろ過し、このフイルタ前後
の圧力差を差圧計によつて測定して固体微粒子を
測定し、その下流で、ろ過された排気ガス中の炭
化水素、すなわち、液状微粒子の量を加熱型水素
炎イオン化検出器によつて測定するので、排気ガ
ス中の固体微粒子および液状微粒子各々の排出量
を区別して、連続的かつ高精度に測定することが
できる。
As mentioned above, the apparatus for measuring particulates in exhaust gas according to the present invention filters the exhaust gas heated to a temperature at which all the hydrocarbons in the exhaust gas introduction pipe are vaporized through the filter, and The solid particulates are measured by measuring the pressure difference with a differential pressure gauge, and downstream of that, the amount of hydrocarbons, that is, liquid particulates, in the filtered exhaust gas is measured with a heated hydrogen flame ionization detector. Therefore, the amounts of solid particles and liquid particles in the exhaust gas can be distinguished and measured continuously and with high precision.
図面はこの発明に係る測定装置の一実施例を示
す配管図である。
１……排気ガス導入管、２……加熱オーブン、
３……加熱オーブン、４……電磁弁、５……フイ
ルタ、６……流量調整バルブ、７……試料採取ポ
ンプ、８……オリフイス、９……流量制御装置、
１０……モータ、１１，１２……差圧計、１３…
…圧力計、１４……温度計、１５……演算器、１
６……サンプルキヤピラリ、１７……加熱型水素
炎イオン化検出器、１８……基準ガス導入管、１
９……ゼロガス導入管、２０……スパンガス導入
管、２１，２２……電磁弁、２３……分岐管、２
４……圧力調整器、２５……圧力計、２６……流
量計、Ｇ１……排気ガス、Ｇ２……ゼロガス、Ｇ
３……スパンガス。
The drawing is a piping diagram showing an embodiment of the measuring device according to the present invention. 1...Exhaust gas introduction pipe, 2...Heating oven,
3... Heating oven, 4... Solenoid valve, 5... Filter, 6... Flow rate adjustment valve, 7... Sample collection pump, 8... Orifice, 9... Flow rate control device,
10... Motor, 11, 12... Differential pressure gauge, 13...
...Pressure gauge, 14...Thermometer, 15...Calculator, 1
6...Sample capillary, 17...Heating type hydrogen flame ionization detector, 18...Reference gas introduction tube, 1
9... Zero gas introduction pipe, 20... Span gas introduction pipe, 21, 22... Solenoid valve, 23... Branch pipe, 2
4...Pressure regulator, 25...Pressure gauge, 26...Flow meter, G1...Exhaust gas, G2...Zero gas, G
3...Span gas.
Claims (1)
の排気ガス導入管の中途に設けられたフイルタ
と、このフイルタを通過する排気ガスを、排気ガ
ス中の全ての炭化水素が気化する温度まで加熱す
る加熱装置と、前記フイルタの前後の圧力差を検
出する差圧計と、前記排気ガス導入管の終端に接
続された加熱型水素炎イオン化検出器と、前記差
圧計および前記加熱型水素炎イオン化検出器の検
出信号の変化に基づいて排気ガス中の固体微粒子
および液状微粒子の量を算出する演算器と、を備
えている排気ガス中の微粒子の測定装置。1 Heat the exhaust gas introduction pipe into which exhaust gas is introduced, the filter installed in the middle of this exhaust gas introduction pipe, and the exhaust gas that passes through this filter to a temperature at which all the hydrocarbons in the exhaust gas are vaporized. a heating device for detecting the pressure, a differential pressure gauge for detecting the pressure difference before and after the filter, a heating type hydrogen flame ionization detector connected to the terminal end of the exhaust gas introduction pipe, the differential pressure gauge and the heating type hydrogen flame ionization detector. A device for measuring particulates in exhaust gas, comprising: a calculator that calculates the amount of solid particulates and liquid particulates in exhaust gas based on a change in a detection signal of the device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58036908A JPS59162437A (en) | 1983-03-07 | 1983-03-07 | Device for measuring fine particles in exhaust gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58036908A JPS59162437A (en) | 1983-03-07 | 1983-03-07 | Device for measuring fine particles in exhaust gas |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59162437A JPS59162437A (en) | 1984-09-13 |
| JPH0421811B2 true JPH0421811B2 (en) | 1992-04-14 |
Family
ID=12482872
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58036908A Granted JPS59162437A (en) | 1983-03-07 | 1983-03-07 | Device for measuring fine particles in exhaust gas |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59162437A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015115287A1 (en) * | 2014-01-29 | 2015-08-06 | 株式会社村田製作所 | Measurement method and measurement device for object to be measured |
-
1983
- 1983-03-07 JP JP58036908A patent/JPS59162437A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59162437A (en) | 1984-09-13 |
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