JP2006284508A - On-vehicle exhaust gas analyzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an on-vehicle exhaust gas analyzer that reduces power consumption, and can accurately calculate each measured component concentration in exhaust gas. <P>SOLUTION: The on-vehicle exhaust gas analyzer comprises a drain separator connected with an exhaust pipe of a vehicle via a non-heating introduction pipe, a measuring apparatus group for measuring the moisture concentration in the exhaust gas and concentration of the measured component in a semi-DRY state where liquid moisture is removed by the drain separator, a DRY concentration calculation section for calculating the concentration of the measured component in the exhaust gas in a DRY state where moisture is completely removed based on the moisture concentration and the measured component concentration measured by the measuring apparatus group, and an actual concentration calculation section for calculating the concentration of the measured component contained in the exhaust gas at an exhaust time from the vehicle based on the concentration in the DRY state and a predetermined conversion formula. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle-mounted exhaust gas analyzer that has reduced power consumption and excellent analysis accuracy.

Recently, mobile exhaust sources such as automobiles and airplanes, and exhaust gases from fixed sources such as thermal power plants and incinerators are said to be one of the causes of air pollution. It is also considered to be a cause of adverse health effects. For this reason, in order to analyze components such as CO, CO ₂ , NO _X , and THC (hydrocarbon) contained in exhaust gas from such emission sources, each business operator and local governments use an infrared gas analyzer (hereinafter referred to as NDIR analysis). total also referred), referred to as a chemiluminescent nitrogen oxide analyzer (hereinafter CLD type NO _X total) and also referred to) measurement instrument using the facilities exhaust gas analyzer, such as a flame ionization detector (hereinafter FID meter ing.

In such an exhaust gas analyzer, the sample gas is introduced into each measuring instrument via an introduction pipe, and in the exhaust gas from the exhaust source as described above, CO, CO ₂ , NO, which are components to be measured. _Since H ₂ O is mixed with _{X 2} , THC, and the like, moisture (H ₂ O) in the sample gas is condensed inside the introduction tube when the introduction tube is not heated. When such condensation occurs, the volume of the sample gas decreases and the concentration of the component to be measured is calculated higher than the original concentration. Therefore, in general exhaust gas analyzers, an exhaust gas introduction pipe is used. A heating introduction pipe equipped with a heater is used.

In addition, when the CO and CO ₂ concentrations are measured by the NDIR analyzer, if moisture is contained in the sample gas, for example, when CO is a component to be measured, the infrared absorption wavelength region by the CO and moisture ( Since the absorption wavelength region by H ₂ O) is close, moisture contained in the sample gas causes moisture interference and affects the measured value of CO analysis. Further, if the moisture concentration in the sample gas is not stable, the influence of the sample gas changes, so that an error occurs in the CO measurement value.

On the other hand, in the CLD type NO _X meter, light in the ultraviolet region is detected by a photosensor, but the light emission amount changes in proportion to the amount of NO _X molecules. The NO _X concentration in the sample can be detected from the amount of luminescence.
At this time, it is known that if moisture (H ₂ O) or CO ₂ exists, the amount of light emission decreases. This is the phenomenon called quenching (quenching effect) affects the NO _X measurements. Since more moisture concentration in the sample gas changes its effect if not stable, an error also occurs in the NO _X measurements.

Therefore, in order to solve the problems of moisture interference in the NDIR analyzer, quenching in the CLD type NO _X meter, and instability of the moisture concentration, a general exhaust gas analyzer is provided with a dehumidifier. Yes.

However, in order to eliminate the above-mentioned inconvenience caused by the presence of moisture (H ₂ O) in the exhaust gas, the heating introduction pipe and dehumidifier provided in a general exhaust gas analyzer are consumed. Electricity is large and accounts for most of the power consumption of the exhaust gas analyzer (Patent Document 1).

  Conventionally, exhaust gas analyzers for analyzing components contained in exhaust gas discharged from automobiles are generally installed at indoor experimental facilities, and are analyzed by running experiments indoors. However, recently, as interest in the effects of exhaust gas components on the environment and human health has increased, it is required to analyze the exhaust gas emitted from automobiles when actually driving on the road surface. It has become like this.

In order to mount an exhaust gas analyzer on a car, it is necessary to reduce the size, weight and power consumption, but as described above, the exhaust gas analyzer eliminates the influence of moisture mixed in the exhaust gas. For this reason, since a heating introduction pipe and a dehumidifier with high power consumption are provided, it is difficult to save power.
JP 2002-5838 A

  Accordingly, the present invention is intended to provide a vehicle-mounted exhaust gas analyzer with reduced power consumption while eliminating the influence of moisture mixed in the exhaust gas on the measurement result.

That is, the vehicle-mounted exhaust gas analyzer according to the present invention is a vehicle-mounted exhaust gas analyzer that measures the concentration of components to be measured such as NO _x , THC, CO, and CO ₂ contained in exhaust gas discharged from the vehicle. A drain separator connected to an exhaust pipe of a vehicle via a non-heating introduction pipe, and a moisture concentration in the exhaust gas and a concentration of a measurement target component in a semi-DRY state in which liquid moisture is removed by the drain separator DRY which calculates the concentration of the measurement target component in the exhaust gas in the DRY state in which moisture has been completely removed, based on the measurement device group for measuring water, and the moisture concentration and measurement target component concentration measured by the measurement device group Based on the concentration calculation unit, the concentration in the DRY state, and a predetermined conversion formula, the concentration of the measurement target component contained in the exhaust gas at the time of exhaust from the vehicle is calculated. Characterized in that it comprises a real concentration calculator for.

  In such a case, the power consumption can be reduced by using a non-heating type introduction pipe, and the moisture in the condensed sample gas can be reduced by connecting a drain separator to the introduction pipe. Can be discharged. The drain separator here does not require a complicated structure or temperature control, and may simply remove liquid moisture contained in the exhaust gas. Furthermore, the DRY concentration of the measurement target component in the exhaust gas can be calculated by measuring the concentration of moisture remaining in the sample gas and the concentration of the measurement target component with the measurement device group, and further, from the DRY concentration in advance By using the determined conversion formula, it is possible to calculate the concentration of the component to be measured contained in the exhaust gas at the time when it is discharged from the vehicle by eliminating the influence of moisture contained in the exhaust gas. Therefore, according to the vehicle-mounted exhaust gas analyzer of the present invention, it is possible to calculate the concentration of the measurement target component with high accuracy while reducing the power consumption and suppressing the influence of moisture contained in the exhaust gas. .

More specifically, the vehicle-mounted exhaust gas analyzer of the present invention is more specifically capable of measuring NO _X , THC, CO, and CO ₂ that are measurement target components contained in the exhaust gas discharged from the vehicle. A vehicle-mounted type for measuring the concentration, respectively, a drain separator connected to the exhaust pipe of the vehicle via an unheated introduction pipe, an infrared gas analyzer for measuring the concentrations of CO, CO ₂ and H ₂ O, NO _A component to be measured in exhaust gas in a semi-DRY state in which liquid moisture is removed by the drain separator, including a chemiluminescent nitrogen oxide analyzer for measuring _X concentration and a hydrogen flame ionization detector for measuring THC a measurement device group for measuring the concentration, on the basis of the measurement target component concentration and H _{2 O} concentration measured by the measurement device group, in the exhaust gas at DRY condition moisture was completely removed Based on the DRY concentration calculation unit for calculating the concentration of the measurement target component and the concentration in the DRY state and a predetermined conversion formula, the concentration of the measurement target component contained in the exhaust gas at the time of exhaust from the vehicle is calculated. Examples include an actual density calculation unit for calculating.

  In order to further reduce power consumption, it is preferable to use only a drain separator as a moisture removal mechanism, that is, a device that does not include a dehumidifier with high power consumption.

  By eliminating the dehumidifier and the heater as much as possible, the error from the actual measurement value due to the mutual influence of the measurement target components becomes significant, but this leads to structural complications etc. In order to be able to solve by software, the deviation from the true value that occurs in part or all of each actual measurement value is corrected based on part or all of each actual measurement value, and in the semi-DRY state A correction unit that calculates a true measurement value of each measurement target component is further provided, and the DRY concentration calculation unit calculates the concentration of each measurement target component in the DRY state based on the true measurement value obtained by the correction unit. It is preferable to calculate.

As a preferred specific embodiment, the correction unit performs an intermediate correction on the measured values of CO concentration, CO ₂ concentration and H ₂ O concentration based on the measured value of THC concentration by the flame ionization detector, and CO 2 and on the basis of the intermediate correction value of the intermediate correction value and H _{2 O} concentration in the CO ₂ concentration, with further corrects the intermediate correction value of the CO and CO ₂ concentration, with respect to NO _X concentration, the measured value, the CO by corrected based on the correction value of ₂ concentration and H _{2 O} concentration, it can include those for calculating the true measure of the measurement target component in the semi-DRY state.

  As described above, according to the present invention, the concentration of each measurement target component in the exhaust gas can be calculated with high accuracy while saving power. Therefore, according to the present invention, it is possible to provide an exhaust gas analyzer suitable for mounting on a vehicle.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
The vehicle-mounted exhaust gas analyzer includes a flow path system for circulating exhaust gas discharged from an automobile, and three measuring devices provided on the flow path system for measuring various component concentrations in the exhaust gas. That is, an infrared gas analyzer 4 that measures the concentration of CO, CO _2, and H ₂ O, a flame ionization detector 5 that measures the concentration of THC, and a CLD that measures the concentration of NO _{X in} the exhaust gas that is the sample gas A type NO _X meter 6 and an information processing device 7 that collects measurement result data from each measuring device and controls valves and the like arranged in the flow path system are provided.

The flow path system includes a main flow path 1 that serves as a bypass path that allows most of the exhaust gas to pass therethrough, and a plurality of sub flow paths that are branched from the main flow path 1 and provided in parallel. An infrared gas analyzer 4 is provided on 1, and a flame ionization detector 5 and a CLD type NO _X meter 6 are provided on the auxiliary flow path, respectively.

  The main channel 1 has an upstream end opened as a main port 11, and a suction pump 19 is disposed on the most downstream side. Then, an exhaust gas pipe of a vehicle is connected to the main port 11 and sucked by the suction pump 19 so that an amount necessary for measurement of the exhaust gas is introduced into the main flow path 1. Yes.

  More specifically, on the main channel 1, following the main port 11, an introduction pipe 12, a drain separator 13 for removing liquid water contained in the exhaust gas, a filter 14, and a flow rate control pipe (capillary) 15 a. The branching unit 16, the infrared gas analyzer 4, the pressure control valve 17a, the flow rate control pipe (capillary) 15b, the merging unit 18, the pressure control valve 17b, and the suction pump 19 are arranged in series in this order. The pressure control valve 17a connected to the downstream side of the infrared gas analyzer 4 is for controlling the pressure of the flow path system between the capillaries. The infrared gas analyzer 4 cooperates with each capillary. It plays the role of keeping the flow rate and pressure of the exhaust gas flowing through the chamber constant.

  In the vehicle-mounted exhaust gas analyzer, a non-heating type without a heating device is used as the introduction pipe 12. For this reason, the exhaust gas discharged from the vehicle is rapidly cooled to room temperature in the introduction pipe 12, and moisture contained in the exhaust gas is condensed and adheres to the inside of the introduction pipe 12 as liquid moisture. It is discharged out of the introduction pipe 12 by the separator 13.

  Two branch passages are branched from the branch section 16, and the downstream end of the sub-flow paths is connected to the main flow path 1 again at the junction 18.

  A flame ionization detector 5 for measuring the concentration of THC in the exhaust gas is provided on one of the sub flow paths 2 (first sub flow path). A flow rate control tube (capillary) 21 is provided upstream of the hydrogen flame ionization detector 5, and a flow rate necessary for measuring the concentration of THC (a little compared to the exhaust gas flow rate flowing through the main flow path 1). Is configured to flow through the hydrogen flame ionization detector 5.

On the other sub-flow path 3 (a second sub-flow path), a flow control tube (capillary) 31, CLD type NO _X analyzer 6 are arranged in this order from the upstream. The flow rate control pipe (capillary) 31 restricts the amount of gas flowing through the sub-flow channel 3 to a flow rate necessary for measuring the concentration of nitrogen oxides (which is small compared with the flow rate of exhaust gas flowing through the main flow channel 1). Is.

Note that the pressure control valve 17b connected to the merging portion 18 or downstream thereof is for controlling the pressure of the sub-flow channel described later, and cooperates with the capillary provided in the upstream portion of each sub-flow channel. work was responsible for keeping the flow rate and pressure of the exhaust gas constant flowing hydrogen flame ionization detector 5 and the CLD type NO _X meter 6.

  In general exhaust gas analyzers, a dehumidifier is provided upstream of each measuring device. However, in this vehicle-mounted exhaust gas analyzer, a mechanism for removing moisture from sample gas is used to reduce power consumption. It is preferable that only the drain separator 13 is provided and no dehumidifier is provided.

Next, an outline of each measuring device will be described.
Since the infrared gas analyzer 4 has the property that CO, CO ₂ , H ₂ O, etc. each absorbs infrared light having a specific wavelength, the sample gas is irradiated with infrared light of each wavelength, and the absorbance thereof. By detecting this, the amount (concentration) of CO, CO ₂ , H ₂ O, etc. can be measured.

The infrared gas analyzer 4 is of a non-dispersive type, and the sample gas (exhaust gas) is irradiated with infrared rays having specific wavelengths that are absorbed by CO, CO ₂ , and H ₂ O, respectively. The light intensity is measured by a photodetector and output. Then, by comparing the output value with a reference value when there is no light absorption, it is possible to calculate the absorbance of light of each wavelength. Since the light absorbance corresponds to the concentration (amount) of each measurement target component, the concentration (amount) of CO, CO ₂ , H ₂ O can be specified from this, but CO, CO ₂ , H ₂ O Since the THC interferes with each other and CO and CO ₂ interfere with each other and H ₂ O also interferes with each other, the values of the respective light absorptions are simply CO, CO ₂ , H ₂ O. There is no one-to-one correspondence with the density of the.

  The flame ionization detector 5 mixes and burns a sample gas (exhaust gas) with a fuel gas (hydrogen gas) at a fixed ratio, and THC contained in the sample gas is ionized at that time. This is a method of detecting and outputting a value, and the amount (concentration) of THC can be calculated from the current value. The hydrogen flame ionization detector 5 is configured such that an auxiliary combustion gas (air) is introduced in addition to the fuel gas.

The CLD type NO _X meter 6 can measure the amount (concentration) of NO _X contained in the exhaust gas, and includes a NO converter 61, an ozone generator 62, a reaction tank 63, an ozone remover 64, a photodetector ( (Not shown). The NO converter 61 converts NO _X into NO, and is provided on one of a pair of parallel paths that divide the introduced exhaust gas into two. Electromagnetic switching valves are provided at the ends of these parallel paths, and the gas is selectively guided to the reaction tank 63 described later only from one of the paths. The ozone generator 62 takes in the atmosphere as it is without dehumidification, converts oxygen contained in the atmosphere into ozone, and outputs the ozone-containing gas. The reaction tank 63 is a housing having a constant volume, and includes a sample gas introduction port 631, an ozone-containing gas introduction port 632, and a lead-out port 633. As described above, the gas from any one of the parallel paths selected by the switching valve is guided to the sample gas introduction port 631, and the ozone-containing gas introduction port 632 contains ozone from the ozone generator 62. Gas is led. These gases mix in the reaction vessel 63 and emit light. The photodetector (not shown) measures the light emission intensity in the reaction vessel 63. In this embodiment, for example, a photomultiplier tube is used as the photodetector. However, since CO ₂ and H ₂ O inhibit the luminescence phenomenon during the reaction (quenching), the concentration of NO cannot be calculated immediately from the value of the luminescence intensity.

  As shown in FIG. 2, the information processing apparatus 7 is a general-purpose or dedicated device including a memory 702, an input / output channel 703, an input means 704 such as a keyboard, a display 705, etc. in addition to the CPU 701. An analog-digital conversion circuit such as an A / D converter 706, a D / A converter 707, and an amplifier (not shown) is connected to 703.

  Then, the CPU 701 and its peripheral devices cooperate with each other according to a program stored in a predetermined area of the memory 702, so that the information processing apparatus 7 is provided in the flow path system as shown in FIG. A control unit 71 that controls the opening and closing of the valves and the temperature control of the heater, an actual measurement value acquisition unit 72 that acquires actual measurement values of the analyzers 4, 5, and 6 with respect to the exhaust gas discharged at the same time, A correction unit 73 that corrects a deviation from a true value occurring in part or all of the actual measurement value, and the concentration of the measurement target component in the exhaust gas in the DRY state in which moisture is completely removed is calculated from the correction value. Based on the DRY concentration calculation unit 74 and the concentration in the DRY state and a predetermined conversion formula, the actual concentration calculation unit 75 calculates the concentration of the measurement target component contained in the exhaust gas at the time of exhaust from the vehicle. To function as. Note that the information processing apparatus 7 does not need to be physically integrated, and may be divided into a plurality of devices by wire or wireless.

The operation of the information processing apparatus 7 configured as described above will be briefly described.
First, the actual measurement value acquisition unit 72 samples and accepts output data from the analyzers 4, 5 and 6 at predetermined time intervals, and performs averaging processing, gain in the amplifier and detector, offset processing, etc. as necessary. Are stored in the actual measurement data storage unit D1 set in a predetermined area of the memory in time series as actual measurement data. The actual measurement value acquisition unit 72 stores in advance the time lag when the exhaust gas reaches the analyzers 4, 5, and 6, and the exhaust gas discharged at the same time based on the time lag. Each measured data related to the gas is extracted from the measured data storage unit D1 and output. For example, at the time when the measured data from the analyzers 4, 5, 6 that the exhaust gas reaches the slowest is acquired, the measured data and the measured data related to the other analyzers 4, 5, 6 are reached. The actual measurement data acquired earlier by the time difference is output.

  Next, the correction unit 73 receives each actual measurement data output from the actual measurement value acquisition unit 72, and sets a value indicated by each actual measurement data, that is, an actual measurement value related to each measurement target component, as a part of each actual measurement value or Correction is made based on the whole, and correction data indicating the correction value is output. More specifically, it will be described below.

  First, with respect to the THC concentration, the correction unit 73 performs zero / span calibration and linearization on the actual measurement value of the flame ionization detector 5, further performs pressure compensation and temperature compensation, and performs THC in the semi-DRY state. Calculate the concentration.

Next, with respect to the CO concentration, the CO ₂ concentration, and the H ₂ O concentration, the correction unit 73 calculates the actual measurement value related to the infrared gas analyzer 4 in the semi-DRY state calculated from the actual measurement value of the THC concentration as described above. The first correction is performed based on the THC concentration.

Thereafter, in order to further correct the mutual interference effect between CO and CO ₂ , the first-corrected values of the CO concentration and the CO ₂ concentration are secondarily corrected based on the mutual values.

The correction value thus obtained (first correction value for H ₂ O concentration, second correction value for CO concentration and CO ₂ concentration) is subjected to zero / span calibration and linearization, and intermediate correction is performed. Get the value.

Next, with respect to the intermediate correction values of the CO concentration and the CO ₂ concentration, the zero point moisture interference is corrected using the intermediate correction value of the H ₂ O concentration, and the moisture coexistence effect at the SPAN point is corrected.

Finally, pressure compensation and temperature compensation are performed on the correction value, and the concentrations of CO, CO ₂ and H ₂ O in the semi-DRY state are calculated.

Next, the correction unit 73 performs zero / span calibration and linearization on the actual measurement value of the CLD type NO _X meter 6 regarding the NO _X concentration.

And the value, CO ₂ and _{H 2} O due to quenching (quenching effect) subjected to correction. Thereafter, the pressure compensation on the correction value, by performing temperature compensation, calculating the concentration of NO _X in the semi-DRY state.

In this way, the correction unit 73 calculates the THC concentration, CO concentration, CO ₂ concentration, and NO _X concentration in the semi-DRY state, and stores the data related to them in the semi-DRY data storage unit D2.

  Next, the DRY concentration calculation unit 74 acquires each data stored in the semi-DRY data storage unit D2, and calculates the DRY concentration that is the concentration of the measurement target component in the exhaust gas in a state where moisture is completely removed. calculate.

The following formula (1) is used to convert from the semi-DRY concentration to the DRY concentration.
X = W × 100 / (100−H ₂ Oconc.) (1)

Here, each parameter in Formula (1) is as follows.
X; DRY concentration W; semi-DRY concentration H ₂ Oconc. ; Water concentration (vol%) in the semi-DRY state

On the other hand, the information processing device 7 receives data on the amount of water vapor in atmospheric pressure, atmospheric temperature, atmospheric humidity, and atmospheric pressure from the corresponding sensors, and further, the fuel burned by the engine of the vehicle under test. accepting a hydrogen carbon atom number ratio by an operator input, or to store the proportion of NO ₂ in NO _X received from CLD type NO _X meter 6, the parameter data obtained by such the parameter data storage unit D3 Yes.

Next, the actual concentration calculation unit 75 acquires the DRY concentration of each component from the semi-DRY data storage unit D2, and from the parameter data storage unit D3, the amount of water vapor in atmospheric pressure, atmospheric temperature, atmospheric humidity, atmospheric pressure, fuel Parameter data indicating the hydrogen carbon atom number ratio and the ratio of NO _{2 in} NO _X is obtained, and the concentration of each component in the DRY state in which moisture is completely removed is calculated based on a predetermined conversion formula

  As the conversion formula, a known conversion formula can be used. For example, the DRY to WET conversion formula described in CFR-1065 represented by the following series of formulas can be given.

C _EXCOMP (t) = C _{EXCOMP_dry} (t) × (1−C _H2O (t))
C _H2O (t) = C _{H2O_dry} (t) / (1 + C _{H2O_dry} (t))
C _{H2O_dry} (t) = α / 2 × χ _Cproddry (t) + χ _{H2Oint dry} (t) / χ _{prod / int dry} (t)
χ _Cproddry (t) = C _{EXCO2_dry} (t + DT _CO2 ) / 100 + C _{EXCO_dry} (t + DT _CO ) / 100 + C _{EXHC_dry} (t + DT _HC ) / 1000000
χ _{prod / int dry} (t) = 1 / {1−1 / 2 × (C _{EXCO_dry} (t + DT _CO ) / 100−α / 2 × χ _Cproddry −C _{EXNO2_dry} (t + DT _NO2 ) / 1000000)}
C _{EXNO2_dry} (t) =
C _{EXNOx_dry} (t) × FNO
χ _{H2Oint dry} (t) = χ _H2Oint / (1−χ _H2Oint )
χ _H2Oint (t) = EXP {−6096.9385 / (T _AMB (t) +273.15) + 21.2409642−2.711193 × 10 ⁻² × (T _AMB (t) +273.15) + 1.673952 × 10 ^-5 × (T _AMB (t ) +273.15) ² + 2.433502 × Ln (T _AMB (t) +273.15)} × RH _AMB (t) / (P _AMB (t) × 1000 × 100)

Here, each parameter in the above formula is as follows.
C _EXCOMP (t); instantaneous emission concentration after conversion to WET at time t (CO, CO ₂ ; vol%, THC, NOx; ppm)
C _{EXCOMP_dry} (t); instantaneous discharge concentration of DRY at time t (measured value)
(CO, CO ₂ ; vol%, THC, NOx; ppm)
C _H2O (t); Moisture ratio in exhaust gas at time t C _{H2O_dry} (t); Moisture ratio in exhaust gas converted to DRY at time t α: Hydrogen carbon atom number ratio of fuel FNO: NO ₂ ratio in NOx (Gasoline; 1, diesel: 0.25, NO ₂ storage catalyst; 0.75)
χ _{H 2 Oint} (t); amount of water vapor in the atmosphere at time t (mol / mol)
T _AMB (t); atmospheric temperature at time t (degC)
RH _AMB (t); atmospheric humidity at time t (RH%)
P _AMB (t); atmospheric pressure at time t (kPa)

In simple terms, this conversion equation is based on the ratio of the number of hydrogen carbon atoms contained in a known fuel and the concentration of each component in the DRY state measured and calculated, and the ratio of H ₂ O contained in the exhaust gas in the DRY state Is a formula that can be converted from the calculated H ₂ O ratio into the WET state of the exhaust gas, that is, the concentration of the measurement target component contained in the exhaust gas at the time of exhaust from the vehicle. By using the conversion formula described in CFR-1065 and the formula for converting the semi-DRY concentration to the DRY concentration, the exhaust at the time when the components are measured by the measuring device group in the semi-DRY state and discharged from the vehicle. The concentration of the measurement target component contained in the gas can be calculated.

The present invention is not limited to the above embodiment. Other methods and configurations for interference and quenching correction are conceivable, and components to be measured are not limited to those shown in the above embodiment. Other analyzers may be used.
In addition, the present invention can be variously modified without departing from the spirit of the present invention.

  According to the present invention, the concentration of each measurement target component in the exhaust gas can be calculated with high accuracy while reducing power consumption and downsizing. Therefore, it is possible to provide an exhaust gas analyzer suitable for mounting on a vehicle according to the present invention.

1 is an overall fluid circuit diagram of an exhaust gas analyzer according to an embodiment of the present invention. The circuit block diagram of the information processing apparatus in the embodiment. The functional block diagram of the information processing apparatus in the embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Main flow path 11 ... Main port 12 ... Introducing pipe 13 ... Drain separator 14 ... Filter 15 ... Flow control pipe (capillary)
DESCRIPTION OF SYMBOLS 16 ... Branch part 17 ... Pressure control valve 18 ... Merge part 19 ... Suction pump 2 ... Subchannel 21 ... Flow control pipe (capillary)
3 ... Sub-channel 31 ... Flow control pipe (capillary)
4 ... infrared gas analyzer 5 ... flame ionization detector 6 ... CLD type NO _X meter 61 ... NO converter 62 ... ozone generator 63 ... reactor 631 ... sample Gas introduction port 632 ... Ozone-containing gas introduction port 633 ... Derivation port 64 ... Ozone remover 7 ... Information processing device

Claims (5)

A vehicle-mounted type that measures the concentration of a component to be measured such as NO _x , THC, CO, CO ₂ contained in exhaust gas discharged from the vehicle,
A drain separator connected to the exhaust pipe of the vehicle via a non-heating introduction pipe;
A measuring instrument group for measuring the moisture concentration in the exhaust gas and the concentration of the measurement target component in the semi-DRY state from which liquid moisture has been removed by the drain separator;
A DRY concentration calculation unit that calculates the concentration of the measurement target component in the exhaust gas in the DRY state in which moisture has been completely removed based on the water concentration and the measurement target component concentration measured by the measurement device group;
A vehicle-mounted type equipped with an actual concentration calculation unit that calculates the concentration of the measurement target component contained in the exhaust gas at the time of being discharged from the vehicle based on the concentration in the DRY state and a predetermined conversion formula Exhaust gas analyzer. A vehicle-mounted type that measures concentrations of NO _x , THC, CO, and CO ₂ that are measurement target components contained in exhaust gas discharged from the vehicle,
A drain separator connected to the exhaust pipe of the vehicle via a non-heating introduction pipe;
An infrared gas analyzer for measuring CO, CO ₂ and H ₂ O concentrations, a chemiluminescent nitrogen oxide analyzer for measuring NO _X concentration, and a flame ionization detector for measuring THC, which are liquefied by the drain separator A measuring device group for measuring the concentration of the component to be measured in the exhaust gas in the semi-DRY state from which moisture has been removed;
A DRY concentration calculation unit that calculates the concentration of the measurement target component in the exhaust gas in the DRY state in which moisture has been completely removed based on the measurement target component concentration and the H ₂ O concentration measured by the measurement device group;
A vehicle-mounted type equipped with an actual concentration calculation unit that calculates the concentration of the measurement target component contained in the exhaust gas at the time of being discharged from the vehicle based on the concentration in the DRY state and a predetermined conversion formula Exhaust gas analyzer.   The vehicle-mounted exhaust gas analyzer according to claim 1 or 2, wherein only the drain separator is provided as a moisture removing mechanism. Deviation from the true value that occurs in part or all of each actual measurement value due to the mutual influence of the measurement target component is corrected based on part or all of each actual measurement value, and each measurement in the semi-DRY state It further includes a correction unit that calculates the true measurement value of the target component,
4. The vehicle-mounted exhaust according to claim 1, wherein the DRY concentration calculation unit calculates a concentration of each measurement target component in a DRY state based on a true measurement value obtained by the correction unit. Gas analyzer. The correction unit is
Regarding the CO concentration, the CO ₂ concentration, and the H ₂ O concentration, the actual measurement values are intermediately corrected based on the actual measurement values of the THC concentration by the hydrogen flame ionization detector, and the intermediate correction values of the CO and CO ₂ concentrations and the H ₂ O concentration are corrected. And further correcting the intermediate correction value of the CO and CO ₂ concentration based on the intermediate correction value of
With respect to the NO _X concentration, the actual measurement values of the measurement target components in the semi-DRY state are calculated by correcting the actual measurement values based on the correction values of the CO ₂ concentration and the H ₂ O concentration. The exhaust gas analyzer according to claim 4.