JPS6337243A - Chemiluminescent type detector - Google Patents

Abstract

PURPOSE:To control the high voltage power source of a detection output so that detection output when a specific light emitting diode is allowed to light, by providing the light emitting diode emitting standard light fitted to chemiluminescence in a light emitting chamber as a standard light source. CONSTITUTION:A red LED light source 9 is provided to the chamber wall 8 of a light emitting chamber 3 as a standard light source. In a usual measuring state, NO-gas and O3-gas are respectively made to flow from a specimen gas inflow passage 5 and an O3-gas inflow passage 6 to generate chemiluminescence in a reaction chamber 4, and the light generated is detected by an automultiplier detector 11 through a window 12 and the signal of said detector 11 is sent to an indicator 14 to be displayed as concn. At the time of calibration, the inflow of the O3-gas is stopped or zero gas is made to flow from the inflow passage 5 as a sample to prevent chemiluminescence and the light source 9 is subsequently allowed to light. The detection signal of the detector 11 at this time enters a comparator 15 to be compared with the reference sensitivity signal from a constant voltage power source 16, and the high voltage power source 13 of the detector 11 is controlled so that the difference between both of them becomes zero.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a chemiluminescent analyzer that is attached to pollution prevention equipment such as exhaust gas monitoring and measures ammonia gas, nitrogen oxides, etc. in exhaust gas. Regarding.

[Conventional technology]

The No gas concentration in the sample gas is measured using a chemiluminescent analyzer that uses a photomultiplier tube to detect the intensity of light emitted when NO gas and 03 gas react, which is generally called the chemiluminescence method. In this case, NO2 in the sample gas sampled from the sample gas inlet is passed through a converter that converts it into NO, and then introduced into a luminescence chamber supplied with 03 gas to react with O:4 gas and emit light. This is done by measuring the intensity of light through a window provided in a part of the light emitting chamber with a detection section consisting of a photodetector.

[Problem that the invention seeks to solve]

However, in a chemiluminescent analyzer, during long-term use, the detector deteriorates, the sensitivity decreases, or the sensitivity decreases due to fogging of the window in the luminescence chamber, dirt in the chamber, etc. In response to this decrease in sensitivity, the user should
Appropriate frequency according to the regular frequency! There was a problem in that the sensitivity of the detection section had to be calibrated by flowing a standard gas into the light emitting chamber each time.

The present invention eliminates the complexity of having to calibrate the sensitivity of a detection section according to the measurement frequency or periodically by flowing a standard gas each time, and calibrates the sensitivity of the detection section without flowing a standard gas. Our goal is to provide a chemiluminescent analyzer that can perform

[Means for solving problems]

In order to achieve the above object, the present invention configures the chemiluminescent analysis n1 as follows.

That is, a chemiluminescent analyzer is equipped with a luminescent chamber that generates chemiluminescence by reacting nitrogen monoxide gas in the introduced gas with ozone gas supplied separately, and a detector that detects the luminescence intensity within the luminescent chamber. A light emitting diode that emits standard light having a wavelength range corresponding to the chemiluminescence is provided in the light emitting chamber to face the detector, and a light emitting diode that emits standard light having a wavelength range corresponding to the chemiluminescence is provided in the light emitting chamber, and a light emitting diode that emits standard light having a wavelength range corresponding to the chemiluminescence is provided, and a light emitting diode that emits standard light having a wavelength range corresponding to the chemiluminescence is provided, and a light emitting diode that emits standard light having a wavelength range corresponding to the chemiluminescence is provided, and a light emitting diode that emits standard light having a wavelength range corresponding to the chemiluminescence is provided, and a The gist of this paper is a chemiluminescent analyzer characterized by calibrating the sensitivity of its detector.

[For production]

The chemiluminescent analyzer according to the present invention configured as described above normally converts NO□ in a sample gas introduced from a flue etc. to N(]
This is converted and introduced into the light emitting chamber, and at the same time, 0. Gas is introduced and No gas reacts with O gas in a single luminescence chamber, and the intensity of the light emitted at this time is detected to measure the concentration.If sensitivity calibration is required, this invention Since a light emitting diode that emits standard light in the wavelength range corresponding to chemiluminescence is installed in the luminescence chamber, chemiluminescence can be achieved by stopping the supply of 03 gas or by flowing zero gas as a sample gas. This can be done by turning on the light emitting diode after stopping 1. In other words, since the light emitted from the light emitting diode is always constant, the high voltage power supply of the detection section is manually adjusted based on this output signal so that the output of standard light from the light emitting diode is constant. mosquito.

Compare the detection signal from the 4+J quasi-sensor with a preset reference sensitivity signal, and control the high voltage power supply using the comparison signal,
By automatically keeping the output signal from the detection section constant, it becomes possible to calibrate the sensitivity of the detection section without flowing a standard gas.

〔Example〕

Next, an embodiment of the chemiluminescent analyzer according to the present invention will be described below with reference to the drawings.

Figure 1 shows a case where a ratio = 4- comparator is provided to automatically check the sensitivity, with one detection system and two detection units.
and a light emitting chamber 3. The light emitting chamber 3 includes a sample gas inflow path 5 and a gas inflow path 6 for introducing the sample gas and the gas into the reaction chamber 4, respectively.
and an exhaust pipe 7 for exhausting gas, and a red L E n light source 9 is installed on the chamber wall 8 as a standard light source.
is provided, and this red (■) is connected to the EDn light source 9 power supply IO. The detection unit 2 is provided with a photomal detector 11 for detecting the amount of light emitted in the luminescent chamber 4, with its light receiving surface facing a window 12 provided in the reaction chamber 4.
A high voltage power supply 13 is connected to the comparator 15, and a constant voltage power supply 16 is connected to the comparator 15. The output side is wired to control a high voltage power supply 13 connected to the photomal detector 11.

In addition, Fig. 2 shows the red L as the standard light source used above.
FIG. 6 shows that ED is in a wavelength range compatible with a photomal detector that measures No-0,0 emission.

In the chemiluminescent analyzer of the embodiment configured as described above, in a normal measurement state, the No gas is introduced from the sample gas inflow path 5, and the 03 gas is introduced from the 03 gas inflow path 6 into the reaction chamber. Chemiluminescence is generated within the cell 4, and the light is detected by the photomal detector 11 through the window 12, and the signal is sent to the indicator 14 and displayed as concentration. On the other hand, during calibration, after stopping the inflow of O gas or flowing zero gas as a sample from the sample gas inflow path 5 to prevent chemiluminescence, the red LE
The D light source 9 is turned on. The detection signal from the photomal detector 11 at this time enters the comparator 15 and is compared with the reference sensitivity signal from the constant voltage power supply 16 set in advance, and the height of the photomal detector 11 is adjusted so that the difference between the two becomes zero. It comes to control the voltage power source I3. In this case, red L E D
Since the zero point signal of the photomal detector 11 changes when the light source 9 stops emitting light, the red LED light source 9 is blinked and control is performed so that the difference becomes the reference sensitivity signal, and the zero point correction is also performed at the same time. can be done.

In addition, in item 2, the signal from the detection section was connected to the comparator in order to automatically calibrate the sensitivity, but the signal was not connected and was displayed on the display, and based on this, the high voltage of the detection section was manually adjusted. It goes without saying that a configuration may also be used in which the power source is controlled to keep the output from the standard light source constant. In addition, in the second embodiment of -1, a red LED light source is used as the standard light source,
Although the detector used is a photomal detector compatible with a red LED light source, the present invention is not limited to this, and other light emitting diodes or photomal detectors that emit standard light compatible with chemiluminescence may be used. This includes semiconductor detectors other than detectors.

〔effect〕

According to the chemiluminescence analyzer according to the present invention described above, since a light emitting diode that emits standard light compatible with chemiluminescence is provided in the luminescence chamber as a standard light source, the detection output when it is turned on is constant. The high-voltage power supply of the detection section can be controlled so that the sensitivity of the detection section can be calibrated without using standard gas, and a chemiluminescent analyzer that can maintain high sensitivity can be obtained.

4 M'JL Explanation of the Drawings Fig. 1 is a configuration diagram showing one embodiment of the chemiluminescence analyzer according to the present invention, and Fig. 2 shows the red LED and photomal detection used in the embodiment of the present invention. FIG.

DESCRIPTION OF SYMBOLS 1...Detection system, 2...Detection part, 3...Light emission chamber, 4...Reaction chamber, 5...Sample gas inflow path, 6...03 Gas inflow path, 7... Exhaust pipe,
8... Chamber wall, 9... Red LED light source,
10... Power supply, 11... Photomal detector, 12
... window, 13 ... high voltage power supply, 14 ... indicator, 15 ... comparator, 16 ... constant voltage power supply.

−8=

Claims (1)

[Claims] 1. A luminescence chamber that causes chemiluminescence by reacting nitrogen monoxide gas in the introduced gas with ozone gas supplied separately;
In this chemiluminescence analyzer, the chemiluminescence analyzer includes a detector for detecting the luminescence intensity in the luminescence chamber, and a standard light having a wavelength range corresponding to the chemiluminescence is provided in the luminescence chamber, facing the detector. 1. A chemiluminescent analyzer, comprising a light emitting diode that emits light, and the sensitivity of the detector is calibrated based on a detection signal of the detector when the light emitting diode is turned on. 2. A comparator is attached to compare the detection signal of the detector when the light emitting diode is lit with a preset reference sensitivity signal, and the power supply circuit of the detector is controlled by the comparison signal sent from the comparator. 2. The chemiluminescent analyzer according to claim 1, wherein the sensitivity of the detector is calibrated.