CN216484599U - Multichannel gas pollutant concentration spectrum monitoring device - Google Patents
Multichannel gas pollutant concentration spectrum monitoring device Download PDFInfo
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- CN216484599U CN216484599U CN202122580698.7U CN202122580698U CN216484599U CN 216484599 U CN216484599 U CN 216484599U CN 202122580698 U CN202122580698 U CN 202122580698U CN 216484599 U CN216484599 U CN 216484599U
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- 238000012806 monitoring device Methods 0.000 title claims abstract description 24
- 239000003344 environmental pollutant Substances 0.000 title claims abstract description 20
- 231100000719 pollutant Toxicity 0.000 title claims abstract description 20
- 238000001228 spectrum Methods 0.000 title claims abstract description 19
- 230000007246 mechanism Effects 0.000 claims abstract description 48
- 239000006185 dispersion Substances 0.000 claims abstract description 8
- 230000003287 optical effect Effects 0.000 claims description 24
- 238000001914 filtration Methods 0.000 claims description 3
- 230000003595 spectral effect Effects 0.000 claims description 3
- 238000012544 monitoring process Methods 0.000 claims description 2
- 230000009466 transformation Effects 0.000 claims description 2
- 238000000605 extraction Methods 0.000 claims 1
- 239000007789 gas Substances 0.000 abstract description 29
- 238000001514 detection method Methods 0.000 abstract description 6
- 238000005086 pumping Methods 0.000 abstract description 5
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 6
- 210000003437 trachea Anatomy 0.000 description 5
- 238000010521 absorption reaction Methods 0.000 description 4
- 238000005259 measurement Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- -1 NO3 free radical Chemical class 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 238000003916 acid precipitation Methods 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 150000003254 radicals Chemical class 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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Abstract
The utility model discloses a multichannel gas pollutant concentration spectrum monitoring device, which comprises a light outlet mechanism, a sealed cavity, a light inlet mechanism, a pumping mechanism and an acquisition card, wherein the light outlet mechanism is arranged on the sealed cavity; different laser light sources are generated by the light-emitting mechanisms, so that the concentration of various atmospheric gases can be measured, and the measuring efficiency of the monitoring device is improved; by replacing the light-emitting mechanism, laser with different wavelengths can be generated, and the universality of the detection device is improved; the dispersion and the light attenuation of the gas sealed cavity are realized by sharing one sealed cavity and arranging a plurality of virtual light paths in the sealed cavity, so that the complexity of the spectrum monitoring device is reduced; by controlling the air pumping mechanism, the bottom ring-down time information of the air exhaust is measured, and then the ring-down time information of the gas to be detected is measured, so that the accuracy and precision of the detection device are improved.
Description
Technical Field
The utility model relates to the field of spectrum detection, in particular to a multichannel gas pollutant concentration spectrum monitoring device.
Background
The economy develops rapidly and the air quality is more and more emphasized by people, NO2 is an important atmospheric pollutant, and excessive NO2 can damage the atmospheric ozone layer and form acid rain; the NO3 free radical is the most important oxidant in the atmosphere at night, the NO3 free radical reacts with NO2 to generate N2O5, and the concentration of the N2O5 can have important influence on the atmosphere environment, so that the accurate measurement of the concentration of the same type of pollutant gas in the atmosphere has important significance.
At present, the laser wavelength range of most of spectrum monitoring instruments is fixed, and only the gas concentration with an effective absorption cross section in the wavelength range can be measured, and because the gas components in the atmosphere are complex, the dynamic conversion process of various gases and molecular free radicals in different time periods exists, and the measurement of the concentration of a single gas is not easy to accurately reflect the concentration state of a certain gas in the atmosphere.
The multichannel gas pollutant concentration spectrum monitoring device is convenient to carry, simple to operate and capable of continuously measuring multiple same types of pollutant gases in the atmosphere.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a multichannel gas pollutant concentration spectrum monitoring device, which solves the problem that the measured gas in an optical detection device in the prior art is too single.
The purpose of the utility model can be realized by the following technical scheme:
a multichannel gas pollutant concentration spectrum monitoring device comprises a sealed cavity, light path forming components distributed in an array mode are arranged on the circumference of the sealed cavity, each light path forming component comprises a light inlet mechanism and a light outlet mechanism which can be detachably arranged, the light outlet mechanisms and the light inlet mechanisms are distributed alternately, a virtual light path is formed between each light outlet mechanism and each light inlet mechanism, supporting legs distributed in the array mode are obliquely arranged below the sealed cavity, an air pump is arranged on the sealed cavity, a first air pipe and a second air pipe are communicated on the air pump, the second air pipe is communicated with the sealed cavity, an air valve is arranged on the first air pipe, a filter is arranged on the second air pipe, and a barometer is arranged in the sealed cavity; the light inlet mechanism comprises an acquisition card, laser after dispersion attenuation in the sealed cavity enters the light inlet mechanism in an optical signal mode, is converted into an electric signal and is acquired by the acquisition card, and the concentration of the gas to be detected is obtained after the multiple convolution, transformation and fitting of the acquisition card.
Further, the light-emitting mechanism includes first supporting sleeve, and the one end and the sealed chamber intercommunication of first supporting sleeve are equipped with concave mirror, optical isolator, diaphragm, semi-reflection concave mirror, pumping and total reflection concave mirror in proper order in the first supporting sleeve, and the concave mirror is located the one end that is close to the sealed chamber in the first supporting sleeve, and semi-reflection concave mirror, pumping and total reflection concave mirror constitute the resonant cavity that forms laser.
Furthermore, the light incidence mechanism comprises a second supporting sleeve and a third supporting sleeve which are perpendicular to each other, one end of the third supporting sleeve is communicated with the sealed cavity, a high-reflection mirror is arranged between the second supporting sleeve and the third supporting sleeve, a photomultiplier is arranged in the second supporting sleeve, a concave mirror and a narrow-band light filter are arranged in the third supporting sleeve, the narrow-band light filter is located between the concave mirror and the high-reflection mirror, the concave mirror is close to the sealed cavity, and the light filter and the high-reflection mirror are used for filtering stray light.
Furthermore, the acquisition card is connected with the photomultiplier to acquire the electric signal.
Furthermore, laser passes through the diaphragm, stray light is inhibited from passing through, a laser beam is obtained, then the laser beam passes through the optical isolator, the optical isolator only allows the laser beam to pass through from the diaphragm side in a single direction, the passing light beam passes through the concave mirror and enters the sealed cavity, the light beam entering the sealed cavity continues to contact the concave lens of the light inlet mechanism along the direction parallel to the virtual light path and is reflected to the concave lens, dispersion and ring-down are generated in the concave lens, the concave lens and the high-reflection cavity formed by the virtual light path contained in the concave lens, a ring-down signal passing through the concave mirror reaches the high-reflection mirror, only the laser parallel to the axis of the virtual light path is reflected to the photomultiplier, the photomultiplier converts the optical signal into an electrical signal, and the electrical signal is transmitted to the acquisition card.
The utility model has the beneficial effects that:
1. the monitoring device of the utility model realizes the measurement of the concentration of various atmospheric gases by generating different laser light sources through a plurality of light-emitting mechanisms, thereby improving the measurement efficiency of the monitoring device; by replacing the light-emitting mechanism, laser with different wavelengths can be generated, and the universality of the detection device is improved;
2. the monitoring device of the utility model realizes the dispersion and the light attenuation of the gas sealed cavity by sharing one sealed cavity and arranging a plurality of virtual light paths in the sealed cavity, thereby reducing the complexity of the spectrum monitoring device; by controlling the air pumping mechanism, the bottom ring-down time information of the air exhaust is measured, and then the ring-down time information of the gas to be detected is measured, so that the accuracy and precision of the detection device are improved.
Drawings
The utility model will be further described with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of the structure of the spectral monitoring device of the present invention;
FIG. 2 is a schematic diagram of a light-emitting mechanism according to the present invention;
FIG. 3 is a schematic view of the structure of the light incident mechanism according to the present invention;
FIG. 4 is a schematic diagram of a part of the structure of the spectrum monitoring device of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The utility model provides a multichannel gaseous pollutant concentration spectrum monitoring devices, monitoring devices is including sealed chamber 4, as shown in fig. 1, be equipped with array distribution's light path formation part in the circumference of sealed chamber 4, light path formation part includes light incident mechanism 2 and can dismantle the light emitting mechanism 1 that sets up, light emitting mechanism 1 and light incident mechanism 2 alternate distribution, form virtual light path 21 between light emitting mechanism 1 and the light incident mechanism 2, as shown in fig. 4, the below slope of sealed chamber 4 is equipped with array distribution's supporting legs 3, be equipped with air pump 6 on the sealed chamber 4, the intercommunication has first trachea 8 and second trachea on the air pump 6, second trachea and sealed chamber 4 intercommunication, be equipped with pneumatic valve 7 on the first trachea 8, be equipped with filter 9 on the second trachea, air pump 6 during operation, take out the gas in the sealed chamber 4, form the negative pressure, sealed chamber 4 the aforesaid is equipped with barometer 5.
The light emitting mechanism 1 comprises a first supporting sleeve, as shown in fig. 2, one end of the first supporting sleeve is communicated with the sealed cavity 4, a concave mirror 10, an optical isolator 11, a diaphragm 12, a semi-reflection concave mirror 13, a pump 14 and a total reflection concave mirror 15 are sequentially arranged in the first supporting sleeve, the concave mirror 10 is located at one end, close to the sealed cavity 4, of the first supporting sleeve, and the semi-reflection concave mirror 13, the pump 14 and the total reflection concave mirror 15 form a resonant cavity 16 for forming laser.
The light incidence mechanism 2 comprises a second supporting sleeve and a third supporting sleeve which are perpendicular to each other, as shown in fig. 3, one end of the third supporting sleeve is communicated with the sealed cavity 4, a high-reflection mirror 19 is arranged between the second supporting sleeve and the third supporting sleeve, a photomultiplier 20 is arranged in the second supporting sleeve, a concave mirror 17 and a narrow-band light filter 18 are arranged in the third supporting sleeve, the narrow-band light filter 18 is positioned between the concave mirror 17 and the high-reflection mirror 19, the concave mirror 17 is close to the sealed cavity 4, and the light filter 18 and the high-reflection mirror 19 are used for filtering stray light.
The light mechanism 2 further comprises an acquisition card 23, and the acquisition card 23 is connected with the photomultiplier 20.
When in use, the multichannel gas pollutant concentration spectrum monitoring device starts to work to measure NO and NO in air2、 NO3、N2O5When nitrogen oxides exist, the device is powered on, the air pump 6 starts to work, the air valve 7 is opened, air is pumped out by the air pump 6, the air pressure in the sealed cavity 4 starts to change to generate negative pressure, the negative pressure is displayed by the barometer 5 in real time, and when the air pressure value reaches an ideal value, all the light-emitting mechanisms 1 simultaneously start to workLaser emitted from the resonant cavity 16, but because different gases are measured, effective absorption cross sections are different, laser wavelength is different, 226nm is selected for measuring NO, and NO is measured2409nm is selected and NO is measured3When the particle size is 662 nm;
the laser passes through respective diaphragms 12, stray light is inhibited from passing through, laser beams are obtained, then the beams pass through an optical isolator 11, the optical isolator 11 only allows laser beams to pass through from the diaphragm side in a single direction, the passing beams pass through a concave mirror 10 and enter a sealed cavity 4, the beams entering the sealed cavity continue to be parallel to a virtual optical path, a concave lens 17 contacting with a light inlet mechanism 2 is known and reflected to the concave lens 10, dispersion and ring-down are generated in a high-reflection cavity formed by the concave lens 10, the concave lens 17 and the virtual optical path contained by the concave lens 10, ring-down signals passing through the concave mirror 7 reach a high-reflection mirror 19, at the moment, only the laser parallel to the axis of the virtual optical path is reflected to a photomultiplier 20, the photomultiplier converts optical signals into electric signals, and the electric signals are transmitted to an acquisition card 23;
the acquisition card obtains light ring-down information when the laser with different wavelengths passes through the sealed cavity and the related structure thereof in a vacuum state through operations such as convolution, Fourier transform, fitting and the like, wherein the ring-down information is background ring-down information, and the ring-down time is background ring-down time tau0。
The multichannel gas pollutant concentration spectrum monitoring device obtains stable background ring-down time tau0Then, all the light emitting mechanisms 1 stop working, the air valves 7 are opened slowly, gas in the air starts to enter from the air inlets 8 through the filters 9, water vapor, large-particle pollutants and the like in the air are adsorbed, the numerical value of the barometer 5 starts to approach the local atmospheric pressure slowly, then all the light emitting mechanisms 1 start to work, light beams pass through the diaphragm 12, the optical isolator 11 and the concave lens 10 once in the process and enter the virtual light path 21 of the sealed cavity 4, and at the moment, the sealed cavity 4 contains NO and NO with certain concentration2、NO3、N2O5The intensity of the optical signal reaching the photomultiplier through the high-reflection mirror 19 of the light input means 2 is relatively high because the light attenuation due to the dispersion of the optical signal is more serious due to the contamination of nitrogen oxideThe weak reason is that the photomultiplier 20 is arranged here, and in the sealed cavity 4 containing the oxynitride to be measured, different light attenuation signals are obtained and converted into electric signals, and the electric signals are received by the acquisition card 23, and the stable light attenuation oscillation time τ is obtained through operations such as convolution, fourier transform, fitting and the like.
After the multichannel gas pollutant concentration spectrum monitoring device obtains stable background ring-down time tau 0 and ring-down time tau, NO and NO are obtained from an open source website HITRAN2、NO3、N2O5Obtaining the effective absorption cross section data of the laser of the light emitting mechanism 1 of the equal-pollution nitrogen oxides to obtain the background ring-down time tau0And after the ring-down time tau and the absorption section of the gas to be detected, the acquisition card can calculate the concentration of the gas to be detected through a formula.
In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The foregoing shows and describes the general principles, essential features, and advantages of the utility model. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the utility model as claimed.
Claims (5)
1. A multichannel gas pollutant concentration spectrum monitoring device comprises a sealed cavity (4), light path forming components distributed in an array manner are arranged on the circumference of the sealed cavity (4), the device is characterized in that the light path forming component comprises a light inlet mechanism (2) and a light outlet mechanism (1) which is detachably arranged, the light outlet mechanism (1) and the light inlet mechanism (2) are distributed alternately, a virtual light path (21) is formed between the light outlet mechanism (1) and the light inlet mechanism (2), supporting legs (3) which are distributed in an array mode are obliquely arranged below a sealed cavity (4), an air pump (6) is arranged on the sealed cavity (4), a first air pipe (8) and a second air pipe are communicated with the air pump (6), the second air pipe is communicated with the sealed cavity (4), an air valve (7) is arranged on the first air pipe (8), a filter (9) is arranged on the second air pipe, and a barometer (5) is arranged on the sealed cavity (4); the light-in mechanism (2) comprises an acquisition card (23), laser which is subjected to dispersion attenuation in the sealed cavity (4) enters the light-in mechanism (2) in a mode of optical signals and is converted into electric signals to be acquired by the acquisition card (23), and the concentration of the gas to be detected is obtained after the collection card (23) is subjected to convolution, transformation and fitting for multiple times.
2. The multichannel gas pollutant concentration spectrum monitoring device according to claim 1, characterized in that the light extraction mechanism (1) comprises a first support sleeve, one end of the first support sleeve is communicated with the sealed cavity (4), a concave mirror (10), an optical isolator (11), a diaphragm (12), a semi-reflecting concave mirror (13), a pump (14) and a total reflecting concave mirror (15) are sequentially arranged in the first support sleeve, the concave mirror (10) is positioned at one end of the first support sleeve close to the sealed cavity (4), and the semi-reflecting concave mirror (13), the pump (14) and the total reflecting concave mirror (15) form a resonant cavity (16) for forming laser.
3. The multichannel gas pollutant concentration spectral monitoring device of claim 1, characterized in that the light input mechanism (2) comprises a second supporting sleeve and a third supporting sleeve which are perpendicular to each other, one end of the third supporting sleeve is communicated with the sealed cavity (4), a high-reflection mirror (19) is arranged between the second supporting sleeve and the third supporting sleeve, a photomultiplier (20) is arranged in the second supporting sleeve, a concave lens (17) and a narrow-band filter (18) are arranged in the third supporting sleeve, the narrow-band filter (18) is positioned between the concave lens (17) and the high-reflection mirror (19), the concave lens (17) is close to the sealed cavity (4), and the filter (18) and the high-reflection mirror (19) are used for filtering out stray light.
4. The multi-channel device for spectral monitoring of concentrations of gaseous pollutants as claimed in claim 3, wherein said acquisition card (23) is connected to a photomultiplier (20) for acquiring electrical signals.
5. The multi-channel gaseous pollutant concentration spectrum monitoring device according to claim 1, wherein the laser passes through the diaphragm (12), stray light is inhibited from passing through, and a laser beam is obtained, then the beam passes through the optical isolator (11), the optical isolator (11) only allows the laser beam to pass through from the diaphragm side in one direction, the passed beam passes through the concave mirror (10) and enters the sealed cavity (4), the beam entering the sealed cavity continues to contact the concave lens (17) of the light input mechanism (2) along the direction parallel to the virtual optical path and is reflected to the concave mirror (10), dispersion and ring-down are generated in the high reflection cavity formed by the concave mirror (10) and the concave lens (17) and the virtual optical path contained by the concave mirror, a ring-down signal passing through the concave lens (17) reaches the high reflection mirror (19), and only the laser parallel to the virtual optical path axis is reflected to the photomultiplier (20), and the optical signals are converted into electric signals by the photomultiplier, and the electric signals are transmitted to an acquisition card (23).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122580698.7U CN216484599U (en) | 2021-10-26 | 2021-10-26 | Multichannel gas pollutant concentration spectrum monitoring device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122580698.7U CN216484599U (en) | 2021-10-26 | 2021-10-26 | Multichannel gas pollutant concentration spectrum monitoring device |
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| Publication Number | Publication Date |
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| CN216484599U true CN216484599U (en) | 2022-05-10 |
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| CN202122580698.7U Expired - Fee Related CN216484599U (en) | 2021-10-26 | 2021-10-26 | Multichannel gas pollutant concentration spectrum monitoring device |
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2021
- 2021-10-26 CN CN202122580698.7U patent/CN216484599U/en not_active Expired - Fee Related
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Granted publication date: 20220510 |