WO2022267963A1 - 一种用于复合气体的综合检测装置 - Google Patents

一种用于复合气体的综合检测装置 Download PDF

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WO2022267963A1
WO2022267963A1 PCT/CN2022/099026 CN2022099026W WO2022267963A1 WO 2022267963 A1 WO2022267963 A1 WO 2022267963A1 CN 2022099026 W CN2022099026 W CN 2022099026W WO 2022267963 A1 WO2022267963 A1 WO 2022267963A1
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wavelength
gas
light
scattering
pulse sequence
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PCT/CN2022/099026
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English (en)
French (fr)
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张玉芝
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张玉芝
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    • 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
    • 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
    • G01N15/02—Investigating particle size or size distribution
    • G01N15/0205—Investigating particle size or size distribution by optical means, e.g. by light scattering, diffraction, holography or imaging
    • 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
    • G01N15/02—Investigating particle size or size distribution
    • G01N15/0205—Investigating particle size or size distribution by optical means, e.g. by light scattering, diffraction, holography or imaging
    • G01N15/0211—Investigating a scatter or diffraction pattern
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
    • G01N21/3504—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light for analysing gases, e.g. multi-gas analysis
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/47—Scattering, i.e. diffuse reflection
    • G01N21/49—Scattering, i.e. diffuse reflection within a body or fluid
    • G01N21/53—Scattering, i.e. diffuse reflection within a body or fluid within a flowing fluid, e.g. smoke
    • G01N15/075—

Definitions

  • the invention relates to the field of optical sensors, in particular to a fast, high-precision, high-signal-to-noise ratio composite gas component, concentration, and particle size and concentration detection device for suspended particles.
  • Infrared absorption spectrum detection is a commonly used fast, real-time and high-precision detection method, but this method cannot meet the current actual needs.
  • the infrared absorption spectrum detection method cannot detect the particle size and concentration of suspended particles in the gas.
  • PM2.5 For the current Cities with severe airborne particulate pollution, take PM2.5 as an example, although PM2.5 levels in Chinese cities dropped by an average of 9% in 2019 after falling by 12% in 2018. However, 98% of cities still exceeded the World Health Organization (WHO) guideline value. It can be seen that the particle size and concentration detection of suspended particles in the gas is a necessary detection item.
  • WHO World Health Organization
  • the solutions to these problems mainly include the article "Zhang Xiwen, Li Lijing, Liang Sheng, Zhang Chunxi. New Multi-Wavelength Infrared Synchronous Dust and Gas Concentration Sensor [J]. Infrared Technology, 2009,31(01):35 ⁇ 38. " and the patent “US2017/0097301A1" and mentioned in, do not ignore Lambert-Beer's law
  • the scattering term of the attenuation coefficient K( ⁇ ) restores the attenuation coefficient to the sum of the absorption term and the scattering term. But this method still has serious deficiencies.
  • this method combines the incident light intensity I in ( ⁇ ) and the transmitted light intensity I out ( ⁇ ) of n groups of Lambert-Beer laws under n wavelengths to solve n attenuation coefficients.
  • the attenuation coefficient K( ⁇ ) of suspended particles or gas components is only an absorption term or a scattering term, and the other term is zero.
  • infrared spectroscopy which is a test method that often uses a long test light path in order to improve test accuracy, it is impossible for the absorption item and the scattering item to be zero at the same time. This greatly simplifies the model, but greatly reduces the accuracy of the calculation results.
  • this method determines the particle size and concentration of suspended particles, only the incident light intensity I in ( ⁇ ) and the transmitted light intensity I out ( ⁇ ) are measured by the light absorption method to obtain the particle size and corresponding concentration of suspended particles. It is necessary to predetermine the attenuation coefficient K D ( ⁇ ) of suspended particles with different particle sizes D, which is obviously not feasible in actual rapid measurement.
  • infrared light sources with multiple wavelengths are often used for the measurement of multi-gas components using infrared spectroscopy.
  • Relying on the traditional test method if you want to ensure that there is no interference between the signals of each wavelength, establish a linear equation system of Lambert-Beer's law that is independent and uncoupled.
  • you need to set up The number of detectors with narrow-band filters makes the cost of the test setup multiply with the type of detection.
  • the volume, overall complexity and cost of the device are greatly increased, and errors between different gas chambers are introduced, which reduces the test accuracy.
  • the present invention provides a comprehensive detection device for composite gas.
  • the detection device of the present invention can perform fast, high-precision, high signal-to-noise ratio composite gas component and concentration detection, and preferably simultaneously The particle size and concentration of suspended particles are detected.
  • a comprehensive detection device for compound gas characterized in that the comprehensive detection device includes a multi-wavelength pulse sequence generation module, a first detection unit, a second detection unit, a gas chamber and a signal processing module, and the multi-wavelength pulse
  • the sequence generation module is used to transmit a multi-wavelength pulse sequence to the gas chamber, and the pulse sequence includes a first pulse sequence for scattering measurement and a second pulse sequence for infrared spectroscopy measurement;
  • the first detection unit is arranged at a first position of the gas cell body, and is used for measuring the scattered light of the first pulse sequence
  • the second detection unit is arranged at a second position of the gas cell body, and is used for measuring the output light of the second pulse sequence
  • the signal processing module is configured to: calculate the scattering coefficient of the substance in the gas chamber for at least one wavelength as a reference scattering coefficient based on the measured light and scattered light intensity of the first pulse sequence; simulate the reference scattering coefficient Combine, determine the scattering coefficient relationship between any two wavelengths in each wavelength of the first pulse sequence, and construct a homogeneous scattering coefficient equation; construct an infrared spectrum measurement equation group based on the incident light intensity and outgoing light intensity of each wavelength; and solve the equation set by the homogeneous
  • the simultaneous equation group formed by the scattering coefficient equation and the infrared spectrum measurement equation group determines the concentration of each gas component in the gas chamber.
  • the multi-wavelength pulse sequence generating module is one of the following modules:
  • a module composed of a pulse power supply and multiple laser light sources
  • a module composed of a pulse power supply and multiple LED light sources
  • a module composed of a pulse power supply, a thermal radiation light source, and a plurality of filters distributed along the wall of the gas chamber;
  • a module composed of a pulse power supply, a gas discharge light source and multiple optical filters distributed along the wall of the gas chamber.
  • the first detection unit is located on one side of the inlet of the gas chamber, and is used for light scattering measurement, and measures the scattered light intensity of the multi-wavelength pulsed light at a specific scattering angle in the first pulse sequence and forward scattered light intensity.
  • the second detection unit is located at one side of the main body of the gas cell, and is used to measure the light intensity of the multi-wavelength pulsed light in the second pulse sequence after propagating through the gas cell.
  • the signal processing module includes a filter circuit, a differential amplifier circuit and a single-chip microcomputer chip.
  • the gas chamber includes a gas chamber inlet assembly, an outlet assembly thereof, and a gas chamber main body, all of which have high reflectivity to the multi-wavelength pulsed light in the first and second pulse sequences.
  • the inlet assembly of the air chamber and the main body of the air chamber are internally connected to each other, and the inside is sprayed with a dust-proof coating;
  • the air chamber is characterized by a direct or White type air chamber, a Herriot type air chamber or a Chernin type air chamber.
  • the outlet assembly of the air chamber is used to suck the sample to be tested from the inlet assembly of the air chamber and clean the components in the air chamber through a rapid airflow.
  • the signal processing module performs signal processing in the following manner:
  • is the light intensity of the forward scattered light
  • I 0 is the light intensity of the incident light
  • l is the scattered light path
  • ⁇ a and ⁇ b are two measurement wavelengths
  • I in is the input light intensity
  • I out is the output light intensity
  • the gas concentration is c 1 , c 2 , c 3 ⁇ c n
  • the molar molecular absorption coefficients are respectively
  • the test wavelengths are ⁇ 1 , ⁇ 2 , ⁇ 3 ⁇ n
  • L is the optical path during infrared spectrum measurement
  • the device characterized in that, when the concentration of any gas component is determined, the formula for calculating the concentration of other gas components is:
  • the first detection unit is a CCD, CMOS, thermocouple, thermistor, pyroelectric detector, photoresistor, photodiode, solid-state photomultiplier tube or PIN tube.
  • the second detection unit is a thermocouple, a thermistor, a pyroelectric detector, a photoresistor, a photodiode, a solid-state photomultiplier tube or a PIN tube.
  • the gas flow channel of the air chamber inlet assembly meets the measurement requirements of the light scattering method.
  • the inlet assembly of the air chamber and the main body of the air chamber are internally connected to each other, and the inside is sprayed with a dust-proof coating.
  • the signal processing module is used to amplify, analyze and process the signals detected by the first detection unit and the second detection unit.
  • the present invention is described with PM2.5 and PM10, CO, CO 2 and formaldehyde as examples, those skilled in the art should understand that the present invention can be used for various other Harmful or harmless gases are detected, including but not limited to ammonia, ozone, nitrogen dioxide, sulfur dioxide, etc., and the present invention can also detect particles with other particle sizes, such as 0.5 micron, 1 micron, 5 micron, 8 microns, 15 microns, etc.
  • the invention can not only be applied to the detection of air pollution, but also can be used to measure the concentration of specific gases, such as the determination of the oxygen content in the air and the determination of the concentration of anesthesia gas.
  • the invention can also be applied to the determination of combustible gas concentration in dangerous places where flammable, explosive and toxic gases exist, such as gas, petroleum, chemical industry and metallurgy.
  • the invention can also be used to measure the concentration of dust and other substances.
  • the invention constructs a detection device that can realize not only the measurement of the particle concentration in the gas, but also the measurement of the gas components.
  • the integrated multi-wavelength pulse sequence generation module is used to emit light pulses of several wavelengths into the test gas chamber in the form of a pulse sequence with a repetition frequency of R and a pulse width of ⁇ for testing.
  • the dissipation time t of a single pulse with wavelength ⁇ in the gas chamber satisfies Scattered light collection is performed on the side of the gas cell.
  • the light emitted into the gas chamber this time includes both the measuring light suitable for the measurement by the light scattering method and the measurement light for the subsequent infrared spectrometry measurement.
  • light corresponding to fingerprint wavelengths of PM2.5 and PM10 exists in each wavelength, and light corresponding to fingerprint wavelengths of CO, CO 2 , or formaldehyde exists.
  • k( ⁇ ) is the absorption coefficient
  • ⁇ ( ⁇ ) is the scattering coefficient
  • l is the test optical path.
  • a specific air component absorbs the corresponding detection light with a detection wavelength of ⁇
  • the change of the light intensity of the detection light with a wavelength of ⁇ its Lambert ⁇ Beer law can be written as
  • the size of the corresponding scattering item at the detection wavelength ⁇ is determined, which can eliminate the influence of suspended particles on the measurement results caused by the scattering of the detection light with a wavelength ⁇ , and obtain accurate air component concentrations.
  • the scattering term is mainly produced by suspended particles in the air.
  • the Mie scattering model is suitable for scattering.
  • the test optical path measured by the light scattering method should be as short as possible, for example, shorter than a certain value (this value can be set by those skilled in the art based on experience or experiments).
  • the test light path is extremely short, and the absorption of test light by gas is negligible.
  • the homogeneous scattering coefficient equation, ⁇ a , ⁇ b are two kinds of measurement wavelengths. According to this formula, under the same scattering medium conditions, two groups of two, different wavelengths of test light are substituted into the formula, and multiple homogeneous scattering coefficient equations are obtained to form a group of homogeneous scattering coefficient equations.
  • the present invention transmits light pulses of several wavelengths into the test gas chamber in the form of a pulse sequence with a repetition frequency of R and a pulse width of ⁇ for testing. This allows a single pulse with a wavelength of ⁇ to have a higher peak power and a higher contrast in the detection process. At the same time, it is only necessary to ensure that the dissipation time t of a single pulse with wavelength ⁇ in the gas chamber satisfies
  • the side scattered light intensity I s ⁇ ( ⁇ ) of multiple wavelengths selected under a specific scattering angle is simultaneously measured, based on the side scattered light intensity I s ⁇ ( ⁇ ) and the corresponding incident light intensity, using a light scattering method to measure Get the particle size and corresponding concentration of suspended particles.
  • the measurement of particle size and corresponding concentration of suspended particulate matter can be carried out by existing methods, such as using the title "Key Technology in the Detection System of Respirable Particle Concentration Based on Mie Scattering", Zhang Peng, Taiyuan University of Science and Technology recorded in his master's degree thesis It can be carried out in the same way, but the side scattered light intensity data used is the corrected data.
  • the second detection unit uses infrared absorption spectrum measurement, that is, use infrared spectroscopic detection method for measurement.
  • infrared spectrum detection for the gas component 1, gas component 2, gas component 3...gas component m to be measured, there are corresponding test wavelengths ⁇ 1 , ⁇ 2 , ⁇ 3 ⁇ n , The corresponding molar molecular absorption coefficients are The corresponding measured concentrations are c 1 , c 2 , c 3 . Component 3... There is a strong absorption in the gas component m, and the absorption of the remaining components is negligible.
  • the detection optical path is L (it should be noted that during infrared spectrum measurement, the optical path is preferably not equal to that of the scattering method when measuring the particle concentration), and the infrared spectrum measurement equation group is obtained
  • the concentration of each target gas component can be determined.
  • the present invention provides a fast and high-precision detection device for the composition and concentration of composite gas and the particle size and concentration of suspended particles.
  • the device of the present invention uses a multi-wavelength laser emitting module to send pulse sequences for scattering
  • the measurement light for optical measurement and the measurement light for infrared spectrometry measurement are detected in a differential manner.
  • the required fingerprint wavelengths are sequentially transmitted into the air chamber, and the detection signals are received by 2-3 detection units covering the whole band, which can realize double detection of a single air chamber.
  • the detection of various gas components does not interfere with each other, making the measurement process faster and reducing the requirements for measuring equipment.
  • the present invention utilizes the scattering information in the measurement of the scattering spectrum method to more accurately eliminate the error caused by scattering to the measurement of the infrared spectrum absorption method through the simultaneous connection of the homogeneous scattering coefficient equation and the infrared spectrum absorption method, making the measurement results more accurate .
  • the advantages are more prominent.
  • the detection device of the present invention reduces the number of required detectors, and the more measurement types of the device, the lower the average measurement cost of each component. Moreover, the device can utilize the structure of the existing device, thereby reducing research and development and production costs.
  • the device of the present invention can greatly reduce the production cost in terms of structure simplification and the number of detectors and filters. Moreover, based on the differential detection method, the device of the present invention can realize faster detection with higher precision and higher signal-to-noise ratio.
  • Fig. 1 is the principle schematic diagram of detection device of the present invention
  • Fig. 2 is the schematic diagram of the reflection cavity in the air chamber
  • Figure 3 is a timing signal sent by the multi-wavelength pulse sequence generation module.
  • this embodiment provides a fast, high-precision, high-signal-to-noise ratio composite gas component and concentration detection device. And preferably, it can also detect the particle size and concentration of suspended particles at the same time.
  • the device of the present invention includes a multi-wavelength pulse sequence generation module 1 , a first detection unit 2 , a second detection unit 3 , a gas chamber main body 4 , a gas chamber inlet assembly 5 and an air chamber outlet assembly 6 . The measured gas enters the gas chamber from the gas chamber inlet assembly 5 and flows out from the gas chamber outlet assembly 6 .
  • the multi-wavelength pulse sequence generation module 1 is a module composed of a pulse power supply and four QCL laser light source packages with different central wavelengths, and the central wavelengths correspond to the fingerprint wavelengths (532nm, 640nm) of PM2.5 and PM10 particles respectively, CO 2 's fingerprint wavelength (4.26 ⁇ m) and formaldehyde's fingerprint wavelength (3.56 ⁇ m).
  • the timing trigger mode of multiple wavelength lasers is shown in Figure 3.
  • the multi-wavelength pulse sequence generating module (1) is arranged at the far right end of the gas chamber, and is incident into the gas chamber through the window of the gas chamber.
  • the first detection unit 2 is arranged near the entrance of the gas chamber, and adopts a photodiode responsive to the fingerprint wavelength (532nm, 640nm) of PM2.5 and PM10 particles. It is used for measurement by light scattering method, and measures the scattered light intensity and forward scattered light intensity of dual-wavelength pulsed light at a specific scattering angle.
  • the second detection unit 3 is arranged near the outlet of the gas chamber, and adopts a photodiode responsive to the fingerprint wavelength (4.26 ⁇ m) of CO and formaldehyde (3.56 ⁇ m), and is used to measure the multi-wavelength pulsed light by the infrared spectrum absorption method.
  • the air chamber main body 4 can adopt the structure as shown in FIG. 2 .
  • the gas chamber conforms to the characteristics of the White-type reflective gas chamber, and is composed of 4 concave mirrors with the same curvature radius. In order to obtain a longer optical path, it can also detect when the content of CO 2 and formaldehyde is very small.
  • the inner wall of the air chamber inlet assembly (5) is coated with a dust-proof coating to prolong the service life of the device and increase the detection accuracy.
  • the structure at the inlet assembly (5) of the gas chamber conforms to the principle of fluid mechanics, so that the gas to be measured can flow smoothly in the device.
  • the air chamber outlet assembly (6) is equipped with a low-power silent and vibration-free fan, blowing air toward the outside of the air chamber, so that the sample to be tested is sucked from the inlet of the air chamber, and can operate with the required pulse sequence timing or continuously.
  • the fan has a rapid operation mode. When the device is turned on, the fan can be set to the extreme speed operation mode to clean the air chamber inlet assembly (5), the air chamber main body (4) and the air chamber outlet assembly (6) through the extreme speed operation of the fan, Extend device life.
  • the signal processing module includes a filter circuit, a differential amplifier circuit and an STM32L031G6U6 single-chip microcomputer chip.
  • the sample (gas to be measured) is sent in from the gas chamber inlet assembly (5) and sent out from the gas chamber outlet assembly (6) at a constant flow rate by the fan.
  • the multi-wavelength pulse sequence generation module (1) Start the multi-wavelength pulse sequence generation module (1), so that it emits an optical pulse of a wavelength selected according to needs into the test gas chamber in the form of a pulse sequence with a repetition rate of R and a pulse width of ⁇ .
  • the measuring light pulse of the formaldehyde fingerprint wavelength (3.56 ⁇ m) is to the gas chamber main body (4) (in this embodiment, the emitted light pulse is the light of the above four fingerprint wavelengths, those skilled in the art can Increase the number of wavelengths in the sequence, the more gas components required for a single measurement, the lower the comprehensive cost of the device of the present invention, and the higher the comprehensive benefit), and the test is carried out.
  • the first detection unit (2) uses the pulsed light of the fingerprint wavelength (532nm, 640nm) of PM2.5 and PM10 particles as the measurement light, and use the light scattering method to measure the particle size and corresponding concentration of suspended particles (The light scattering method measurement and the particle size and concentration calculation of the scattering particles can be carried out by existing methods). Select the test light required by the light scattering method from the pulse sequence (for better illustration, only 532nm and 640nm here, but more wavelengths can be selected in practical applications), and determine the scattering coefficient of the selected wavelength.
  • the wavelength of the test light is ⁇
  • the intensity of the outgoing light is I 0 ( ⁇ )
  • the length of the test optical path is l
  • ( ⁇ ) is measured
  • the homogeneous scattering coefficient equation, ⁇ a , ⁇ b are two kinds of measurement wavelengths. According to this formula, under the same scattering medium conditions, two groups of two, different wavelengths of test light are substituted into the formula, and multiple homogeneous scattering coefficient equations are obtained to form a group of homogeneous scattering coefficient equations. This equation set is used to improve the measurement accuracy of subsequent infrared spectroscopy measurements.
  • the second detection unit 3 uses the infrared spectrum detection method to measure.
  • the infrared spectrum detection there are corresponding test wavelengths ⁇ 1 , ⁇ 2 , ⁇ 3 ⁇ n for the gas component 1, gas component 2, gas component 3...gas component n to be measured
  • the corresponding molar molecular absorption coefficients are The corresponding measured concentrations are c 1 , c 2 , c 3 ⁇ c n , and the test wavelengths ⁇ 1 , ⁇ 2 , ⁇ 3 ⁇ n are only compatible with the corresponding gas components 1, Gas component 3...
  • the detection optical path is L, the infrared spectrum measurement equations are obtained
  • CO2 fingerprint wavelength (4.26 ⁇ m) pulsed light and formaldehyde fingerprint wavelength (3.56 ⁇ m) pulsed light are respectively used as measurement light, and infrared spectroscopy is used for measurement to obtain the infrared spectrum measurement equation, and step 3 The obtained equations are combined to obtain a system of equations;
  • the detection device for the composition and concentration of the composite gas and the particle size and concentration of the suspended particles in this embodiment is basically the same as that in Embodiment 1.
  • the device includes a multi-wavelength pulse sequence generation module (1), a first detection unit (2), a second detection unit (3), a gas chamber main body (4), a gas chamber inlet assembly (5), a gas chamber Outlet assembly (6).
  • the multi-wavelength pulse sequence generating module (1) is a module composed of a pulse power supply, two semiconductor laser light sources with different central wavelengths and three infrared LED light sources with different central wavelengths, and the central wavelengths correspond to PM2. 5.
  • the fingerprint wavelength of PM10 particles (dual wavelength), the fingerprint wavelength of CO (4.67 ⁇ m), the fingerprint wavelength of SO 2 (7.26 ⁇ m) and the fingerprint wavelength of methane.
  • the first detection unit (2) is a CCD device responsive to fingerprint wavelengths (dual wavelengths) of PM2.5 and PM10 particles. It is used for the measurement of light scattering method to measure the scattered light intensity and forward scattered light intensity of dual-wavelength pulsed light at a specific scattering angle.
  • the second detection unit (3) is a photoresistor that responds to the fingerprint wavelength of CO , SO2 and methane, and is used to measure multi-wavelength pulsed light after it propagates through the gas chamber main module (4) by infrared spectral absorption method. of light intensity.
  • the main body (4) of the gas chamber conforms to the characteristics of the Chernin type reflective gas chamber, and is composed of three concave mirrors with the same curvature radius, so as to obtain a longer optical path, so that when the content of CO, SO 2 and methane is small can also be detected.
  • the sample (gas to be measured) is sent in from the inlet (5) of the gas chamber and sent out from the outlet (6) of the gas chamber at a constant flow rate by the fan;
  • the measurement light pulses of the fingerprint wavelength (dual wavelength) of PM2.5 and PM10 particles are sent to the end of the air chamber inlet assembly (5) in turn (the first detection unit can also be at the end of (5) Integrated inside the gas cell (4), CO fingerprint wavelength measurement light pulses to the gas cell body (4), SO 2 fingerprint wavelength measurement light pulses to the gas cell body (4), methane fingerprint wavelength measurement light pulses to the gas cell body (4).
  • step 7 Use the methane fingerprint wavelength pulsed light as the most measurement light, use infrared spectroscopy to measure, obtain the infrared spectrum measurement equation, and combine with the equations obtained in step 4 and step 5 to obtain a group of equations. Simultaneously combine the reference scattering coefficient obtained in the above steps, the homogeneous scattering coefficient equation, and the infrared spectrum measurement equation group to determine the size of the scattering item, and use step difference to obtain accurate gas component concentrations.
  • the detection device of this embodiment is basically the same as that of Embodiment 1, comprising a multi-wavelength pulse sequence generation module (1), a first detection unit (2), a second detection unit (3), a gas chamber main body (4), and a gas chamber inlet Assembly (5), chamber outlet assembly (6).
  • the multi-wavelength pulse sequence generation module (1) is a module composed of a pulse power supply, 2 solid-state laser light sources with different central wavelengths and 3 QCL laser light sources with different central wavelengths, and the central wavelengths correspond to PM2. 5. Fingerprint wavelength of PM10 particles (dual wavelength), fingerprint wavelength of CO 2 , fingerprint wavelength of SO 2 and fingerprint wavelength of methane.
  • the first detection unit (2) is a CMOS device that responds to fingerprint wavelengths (dual wavelengths) of PM2.5 and PM10 particles. It is used for the measurement of light scattering method to measure the scattered light intensity and forward scattered light intensity of dual-wavelength pulsed light at a specific scattering angle.
  • the second detection unit (3) is a pyroelectric detector responsive to the fingerprint wavelength of CO2 , the fingerprint wavelength of SO2 and the fingerprint wavelength of formaldehyde, and is used for infrared spectrum absorption method to measure multi-wavelength pulsed light through the main module of the gas chamber ( 4) Light intensity after propagation.
  • the main body (4) of the air chamber conforms to the characteristics of a direct-type air chamber, and has the characteristics of simple structure and low cost.
  • the sample (gas to be measured) is sent in from the inlet (5) of the gas chamber and sent out from the outlet (6) of the gas chamber at a constant flow rate by the fan;
  • the measurement light pulses of the fingerprint wavelengths (dual wavelengths) of PM2.5 and PM10 particles are sequentially transmitted to the end of the gas chamber inlet assembly (5), and the CO2 fingerprint wavelength measurement light pulses are sent to the gas chamber main body ( 4), SO 2 fingerprint wavelength measurement light pulses are sent to the gas chamber main body (4), and methane fingerprint wavelength measurement light pulses are sent to the gas chamber main body (4).
  • the detection device of this embodiment is basically the same as the embodiment, including a multi-wavelength pulse sequence generation module (1), a first detection unit (2), a second detection unit (3), a gas chamber main body (4), and a gas chamber inlet assembly (5), air chamber outlet assembly (6).
  • the multi-wavelength pulse sequence generation module (1) is a module composed of a pulse power supply, two semiconductor laser light sources with different central wavelengths and four infrared LED light sources with different central wavelengths, and the central wavelengths correspond to PM2. 5.
  • the fingerprint wavelength of PM10 particles (dual wavelength), the fingerprint wavelength of CO2 , the fingerprint wavelength of SO2, the fingerprint wavelength of formaldehyde and the fingerprint wavelength of methane ( 3.31 ⁇ m ).
  • the first detection unit (2) is a photodiode device responding to fingerprint wavelengths (dual wavelengths) of PM2.5 and PM10 particles. It is used for the measurement of light scattering method to measure the scattered light intensity and forward scattered light intensity of dual-wavelength pulsed light at a specific scattering angle.
  • the second detection unit (3) is a photoresistor responsive to the fingerprint wavelength of CO2 , the fingerprint wavelength of SO2, the fingerprint wavelength of formaldehyde and the fingerprint wavelength of methane, and is used for infrared spectrum absorption method to measure multi-wavelength pulsed light through the main gas chamber The light intensity after the module (4) propagates.
  • the main body (4) of the gas chamber conforms to the characteristics of the WHITE type reflective gas chamber. It is composed of 4 concave reflectors with the same curvature radius, so as to obtain a longer optical path, so that the content of CO 2 , SO 2 , formaldehyde and methane is very low. It can also be detected when it is small.
  • the sample (gas to be measured) is sent in from the inlet (5) of the gas chamber and sent out from the outlet (6) of the gas chamber at a constant flow rate by the fan;
  • the measurement light pulses of the fingerprint wavelengths (dual wavelengths) of PM2.5 and PM10 particles are sequentially transmitted to the end of the gas chamber inlet assembly (5), and the CO2 fingerprint wavelength measurement light pulses are sent to the gas chamber main body ( 4 ), SO2 fingerprint wavelength measurement light pulses to the gas chamber body (4), formaldehyde fingerprint wavelength measurement light pulses to the gas chamber body (4), methane fingerprint wavelength measurement light pulses to the gas chamber body (4).
  • step 8 Use the methane fingerprint wavelength pulsed light as the most measurement light, use infrared spectroscopy to measure, obtain the infrared spectrum measurement equation, and combine with the equations obtained in step 4, step 5, and step 6 to obtain a group of equations.
  • the device includes the function of detecting the following gases: PM2.5 particulate matter, PM10 particulate matter, formaldehyde, methane, CO 2 , SO 2 , CO, NO 2 , O 3 , ammonia and the like.
  • the device also includes temperature and humidity detection and compensation functions.
  • the device is provided with a communication interface.
  • the power supply mode of the device is external DC power supply or battery power supply.
  • the device can be integrated into air conditioning systems, fresh air systems and other systems as miniature sensors.

Abstract

一种用于复合气体的综合检测装置，包括多波长脉冲序列发生模块（1）、第一探测单元（2）、第二探测单元（3）、气室（4，5，6）以及信号处理模块，多波长脉冲序列发生模块（1）用于进行多波长脉冲序列发射，脉冲序列包括用于散射法测量的第一脉冲序列和用于红外光谱法测量的第二脉冲序列。采用脉冲序列的形式可以同时实现气体中颗粒物浓度以及气体组分的检测，并且检测装置巧妙、准确地消除了气体组分测量中散射的影响，具有结构简单、成本低、测量精度高的优点。

Description

一种用于复合气体的综合检测装置
相关申请
本申请主张于2021年6月25日提交的、名称为“一种用于复合气体的综合检测装置”的中国发明专利申请：202110716203.0的优先权。
技术领域
本发明涉及光学传感器领域，特别涉及一种快速、高精度、高信噪比复合气体组份、浓度及悬浮颗粒的颗粒度、浓度的检测装置。
技术背景
随着社会的发展、科技的进步，人们对于空气质量及安全性的关注度逐年提高。一方面，随着污染的加剧，各种有毒、有害气体，以及颗粒物都使得生活环境中的空气影响到人们的身体健康；另一方面，对于一些特殊生产场景，如矿井、化工厂、建筑场地等，往往充斥着各类有毒气体及粉尘，严重威胁着场地内人们的身体健康，乃至危及人身安全。因此，对于能够快速、实时、高精度的复合气体组份浓度、颗粒度的检测装置的需求也越来越高。
红外吸收谱检测是一种常用的快速、实时、高精度的检测方法，但是这种方法并不能满足目前实际需求，首先红外吸收谱检测方法无法检测气体中悬浮颗粒物的颗粒度及浓度，对于目前空气悬浮颗粒污染严重的城市，以PM2.5为例，虽然中国城市的PM2.5水平在2018年下降了12％之后，在2019年平均下降了9％。但是，98％的城市依旧超过了世界卫生组织(WHO)的准则值。可见气体中悬浮颗粒物的颗粒度、浓度检测是一项必要检测项。其次，在空气中悬浮物浓度高、或者高粉尘污染的应用场景中，红外吸收谱检测方法的精度将大幅降低。对于后者，目前常采用两种解决方案：第一种，忽略悬浮颗粒物散射对测量精度的影响，即使是在中度空气悬浮物污染的生活环境中，这种解决方案都会使得气体组份浓度检测的精度大大降低，并不能真正解决具体问题；第二种，是在检测气室前设置滤网，这种解决方案虽然能够减少悬浮颗粒物散射对测量精度的影响，但需要定期更换滤网，增加了检测设备运维成本。
目前，针对这些问题的解决方案目前主要有文章“张曦雯,李立京,梁生,张春熹.新型多波长红外同步粉尘、气体浓度传感器[J].红外技术,2009,31(01):35‐38.”与专利“US2017/0097301A1”及中所提到的，不忽略Lambert‐Beer定律
I out(λ)＝I in(λ)e -K(λ)L   (1)
衰减系数K(λ)的散射项，将衰减系数还原为吸收项与散射项的求和项。但是这种方法仍存在严重不足。
首先，这种方法将n种波长下n组Lambert‐Beer定律的入射光强I in(λ)与透射光强I out(λ)联立，解出n个衰减系数。为了使得线性方程组有解，需要满足对于任意波长λ，悬浮颗粒物或气体组份的衰减系数K(λ)仅为吸收项或散射项，另一项为零项。但对于红外光谱吸收法这种为了提高测试精度往往采用很长的测试光路的测试方法，吸收项与散射项是不可能同时为零的。这就使得模型大幅简化， 但大大降低了计算结果的准确度。同时，这种方法在确定悬浮颗粒物颗粒度与浓度时，通过光吸收法仅对入射光强I in(λ)与透射光强I out(λ)的测量而得到悬浮颗粒物颗粒度与对应浓度，则需预先确定不同粒径D悬浮颗粒物的衰减系数K D(λ)，显然，在实际快速测量中是不可行的。
其次，正如上述文章与专利中提及的，使用红外光谱法针对多气体组份的测量，往往使用多种波长的红外光源进行测试。依靠传统的测试方法若想保证各个波长信号间相互无干扰，建立相互独立、无耦合的Lambert‐Beer定律的线性方程组，在共用测试气室的情况下，则需要设置与红外光源数量相同的数量的带有窄带滤波片的探测器，使得测试装置的成本随探测种类的增加成倍增加。在非共用气室的情况下，装置的体积、整体复杂程度和成本大大提高，另外还引入了不同气室间的误差，降低了测试精度。
发明内容
本发明为了克服现有技术的不足，提供了一种用于复合气体的综合检测装置，本发明的检测装置能够进行快速、高精度、高信噪比复合气体组份、浓度检测，并且优选同时对悬浮颗粒的颗粒度、浓度进行检测。
一种用于复合气体的综合检测装置，其特征在于，所述综合检测装置包括多波长脉冲序列发生模块、第一探测单元、第二探测单元、气室以及信号处理模块，所述多波长脉冲序列发生模块用于向所述气室进行多波长脉冲序列发射，所述脉冲序列包括用于散射法测量的第一脉冲序列和用于红外光谱法测量的第二脉冲序列；
所述第一探测单元设置于所述气室主体的第一位置处，用于测量所述第一脉冲序列的散射光；
所述第二探测单元设置于所述气室主体的第二位置处，用于测量所述第二脉冲序列的输出光；
所述信号处理模块用于：基于所述第一脉冲序列的测量光和散射光强度，计算所述气室内物质对于至少一种波长的散射系数作为参考散射系数；对所述参考散射系数进行拟合，确定第一脉冲序列各个波长中，任意两种波长的散射系数关系，构建同质散射系数方程；基于各波长的入射光强和出射光强构建红外光谱测量方程组；并求解由同质散射系数方程以及红外光谱测量方程组构成的联立方程组，确定所述气室内各个气体组份浓度。
在一种优选实现方式中，所述多波长脉冲序列发生模块为下述模块之一：
(1)由脉冲电源与多个激光光源组成的模块；
(2)由脉冲电源与多个LED光源组成的模块；
(3)由脉冲电源、热辐射光源与沿气室壁分布的多个滤光片组成的模块；或者
(4)由脉冲电源、气体放电光源与沿气室壁分布的多个滤光片组成的模块。
在另一种优选实现方式中，所述第一探测单元，位于所述气室入口的一侧，用于光散射法测量，测量第一脉冲序列中多波长脉冲光特定散射角的散射光强及前向散射光强。
在另一种优选实现方式中，所述第二探测单元，位于所述气室主体部分的一侧，用于测量第二脉冲序列中多波长脉冲光经气室传播后的光强。
在另一种优选实现方式中，所述信号处理模块包含滤波电路、差分放大电路和单片机芯片。
在另一种优选实现方式中，所述气室包括气室入口组件、其实出口组件及气 室主体，三者对所述第一和第二脉冲序列中的多波长脉冲光具有高反射率。
在另一种优选实现方式中，所述气室入口组件及气室主体内部相互连接，且内部喷涂有防尘涂层；
所述气室符合直射式或者White型气室、Herriot型气室或Chernin型气室的特征。
在另一种优选实现方式中，所述气室出口组件用于将待测样本从所述气室入口组件处吸入并且通过急速气流清洁所述气室内的各组件。
在另一种优选实现方式中，所述信号处理模块采用下述方式进行信号处理：
(1)计算参考散射系数，所述参考散射系数通过前向散射光强测量得到，
其计算公式为：
Figure PCTCN2022099026-appb-000001
其中，I s||为前向散射光的光强，I 0为入射光的光强，l为散射光程；
(2)计算对于不同波长下不同散射系数间关系为：
Figure PCTCN2022099026-appb-000002
其中，λ a、λ b为两种测量波长；
(3)构建红外光谱测量方程组，其表达式为：
Figure PCTCN2022099026-appb-000003
其中，I in为输入光强，I out为输出光强，气体浓度为c 1、c 2、c 3···c n，摩尔分子吸收系数分别为
Figure PCTCN2022099026-appb-000004
测试波长为λ 1、λ 2、λ 3···λ n，L为红外光谱测量时的光程；
(4)求解由上述方程构成的联立方程组。
根据权利要求1所述的装置，其特征在于，当任意气体组分浓度确定后，其他气体组分的浓度计算公式为，
Figure PCTCN2022099026-appb-000005
在另一种优选实现方式中，所述第一探测单元为CCD、CMOS、热电偶、热敏电阻、热释电探测器、光敏电阻、光电二极管、固态光电倍增管或PIN管。
在另一种优选实现方式中，所述第二探测单元为热电偶、热敏电阻、热释电探测器、光敏电阻、光电二极管、固态光电倍增管或PIN管。
在另一种优选实现方式中，所述气室入口组件的气流通道满足光散射法测量要求。
在另一种优选实现方式中，所述气室入口组件及气室主体内部相互连接，且内部喷涂有防尘涂层。
在另一种优选实现方式中，所述信号处理模块用于对第一探测单元、第二探测单元所探测信号进行放大、分析和处理。
需要说明的是，虽然下文实施例中，本发明以PM2.5和PM10，CO、CO 2以 及甲醛等作为示例进行的描述，但是本领域技术人员应该理解，本发明可以用于对各种其他有害或无害气体进行检测，包括但不限于氨、臭氧、二氧化氮、二氧化硫等，并且本发明还可以对其他粒径的颗粒物进行检测，比如，直径为0.5微米、1微米、5微米、8微米、15微米等等。
本发明不仅可以应用于空气污染的检测，还可以用于对特定气体的浓度测定，比如对空气中含氧量的测定，对麻醉气体浓度的测定。本发明还可以应用于燃气、石油、化工、冶金等存在易燃、易爆、毒性气体的危险场所中对可燃气体浓度的测定。本发明还可以用于对粉尘等物质浓度的测定。
发明原理
本发明构建了一个可以实现既能够对气体中颗粒物浓度进行测量，又能够对气体组分进行的测量的检测装置。
首先利用集成的多波长脉冲序列发生模块以重复频率为R，脉冲宽度为τ的脉冲序列的方式，向测试气室中发射若干波长的光脉冲进行测试。单个波长为λ的脉冲在气室内的耗散时间t满足
Figure PCTCN2022099026-appb-000006
在气室侧部进行散射光采集。此次向气室内发射的光既包含适用于光散射法测量的测量光，又包含后续红外光谱法测量的测量光。优选地，各个波长中存在对应PM2.5和PM10的指纹波长的光，并且存在对应于CO、CO 2或甲醛等指纹波长的光。
接下来，利用第一探测单元进行散射光信号采集。
根据Lambert‐Beer定律，将输出光中衰减系数K(λ)写作分立的吸收项与散射项，则有
I out(λ)＝I in(λ)e -[k(λ(+γ(λ)]l   (2)
其中k(λ)为吸收系数，γ(λ)为散射系数，l为测试光程。红外吸收谱检测中，特定空气组份吸收相应的检测波长为λ的检测光，对波长为λ的检测光的光强带来的改变，其Lambert‐Beer定律可以写作
Figure PCTCN2022099026-appb-000007
其中c为气体组份浓度，a m为检测波长下该气体组份的摩尔分子吸收系数，l为测试光程。根据式(3)，确定了检测波长为λ下相应的散射项的大小，即可消除悬浮颗粒物对波长为λ的检测光的散射对测量结果带来的影响，得到准确的空气组份浓度。在这里，散射项主要由空气中的悬浮颗粒物产生。对于悬浮颗粒物，其直径远大于红外吸收谱检测波长，散射适用Mie散射模型。在任意直角坐标系中，假设光强为I 0的入射光沿Z轴正向射入，电矢量沿X轴方向，在距散射颗粒r位置处，散射角为θ，
Figure PCTCN2022099026-appb-000008
与Z轴组成的平面为散射面，
Figure PCTCN2022099026-appb-000009
为入射光振动面与散射面之前的夹角，其散射光强为I s。其Mie散射公式为
Figure PCTCN2022099026-appb-000010
同时，为保证散射的单次不相干，使光散射法测量的测试光程尽量短，比如，短于一定值(该值本领域技术人员可以根据经验或者实验进行设定)。极短的测试 光程，气体对于测试光的吸收可以忽略不计。经散射后，前向散射光的光强I s||可以与无吸收项的Lambert‐Beer定律I out(λ)＝I in(λ)e -γ(λ)L相对应。则可以得到，经过长度为l的散射介质后，对于不同波长下不同散射系数间关系为：
Figure PCTCN2022099026-appb-000011
即为同质散射系数方程，λ a、λ b为两种测量波长。根据此公式，相同散射介质条件下，两两一组，将不同波长测试光分别代入该公式，得到多个同质散射系数方程，构成同质散射系数方程组。
因此，本发明为确保各个波长信号间相互无干扰，以重复频率为R，脉冲宽度为τ的脉冲序列的方式，向测试气室中发射若干波长的光脉冲，进行测试。这样使得单个波长为λ的脉冲拥有更高的峰值功率，在探测过程中拥有更高的对比度。同时只要确保单个波长为λ的脉冲在气室内的耗散时间t满足
Figure PCTCN2022099026-appb-000012
即可确保多种测试光脉冲，在经过气室后进行测量时相互独立。
使用光散射法进行悬浮颗粒物颗粒度及相应浓度的测量。任意从多种波长的测试光中选取测试光，若波长为λ，出射光强为I 0(λ)，测试光程长度为l，并测量前向散射光强I s||(λ)，则得到参考散射系数γ(λ)，其值为
Figure PCTCN2022099026-appb-000013
将所获得的参考散射系数代入式(5)，得到同质散射系数方程。
优选地，同时测量特定散射角下所选取的多波长的侧向散射光强I s⊥(λ)，基于侧向散射光强I s⊥(λ)和相应入射光强，使用光散射法测量得到悬浮颗粒物颗粒度及相应浓度。悬浮颗粒物颗粒度及相应浓度的测量可以采用现有方法进行，比如采用题为“基于Mie散射的可吸入颗粒物浓度检测系统中的关键技术”，张棚，太原科技大学的硕士学位论文中记载的方式进行即可，只是所使用的侧向散射光强数据为经过修正后的数据。
然后，利用第二探测单元进行红外吸收光谱测量，即使用红外光谱检测法进行测量。在红外光谱检测中，对于需要测量的气体组份1、气体组份2、气体组份3···气体组份m，有对应测试波长λ 1、λ 2、λ 3···λ n，对应摩尔分子吸收系数分别为
Figure PCTCN2022099026-appb-000014
对应所需测得浓度为c 1、c 2、c 3···c n，考虑到并不是所有组分都有强吸收，设测试波长仅与对应气体组份1、气体组份2、气体组份3···气体组份m存在较强吸收，其余组份的吸收可以忽略。检测光程为L(需要说明的是，红外光谱测量时，其光程优选与散射法测量颗粒物浓度时不相等)，得到红外光谱测量方程组
Figure PCTCN2022099026-appb-000015
进一步地，联立(5)(7)式即可推导出，在相同悬浮颗粒物状态下，对应红外吸收光谱检测中其他检测波长λ下的散射系数，选择与测试波长相近波长的参考系数通过同质散射系数方程进行散射项求解，确定(8)式中每一项对应散射项的大小，即可消除悬浮颗粒物对波长为λ的检测光的散射对测量结果带来的影响。
在确定了散射项大小的红外光谱测量方程求解过程中，为了提高气体组份浓度的精度，尤其对于摩尔分子吸收系数小的气体。将各个气体组分按照摩尔分子吸收系数自大至小排列，摩尔分子吸收系数大于设定值(本领域技术人员可以根据具体测量精度进行设定)的气体组分，由与其对应的确定了散射项的红外光谱测量方程直接得到其气体组分浓度，其余的两两相邻或相近的气体组份间进行阶梯差分得到准确的气体组份浓度的结果，其运算公式如下
Figure PCTCN2022099026-appb-000016
这样，就可以确定每个目标气体组分的浓度。
与现有技术相比，本发明具有的有益效果为：
1、本发明提供了一种快速高精度复合气体组份、浓度及悬浮颗粒的颗粒度、浓度的检测装置，本发明的装置利用多波长的激光发射模块以脉冲序列的形式分别发送用于散射光测量的测量光和用于红外光谱法测量的测量光，用差分的方式进行检测。检测过程中依次发射所需指纹波长到气室中，并由覆盖全波段的2‐3个探测单元来接收探测信号，能够实现单一气室的双重检测。各种气体组分检测互不干扰，使得测量过程更加快速，同时降低了对测量设备的要求。
2、本发明利用散射光谱法测量时的散射信息通过同质散射系数方程与红外光谱吸收方程的联立，能够更准确地消除散射对红外光谱吸收法测量带来的误差，使得测量结果更加准确。尤其在具有悬浮颗粒物污染的环境中优点更为突出。
硬件上，本发明的检测装置降低了所需探测器的数量，装置的测量种类越多，平均到每种组分的测量成本越低。而且本装置可以利用现有装置的结构，从而降低研发和生产成本。
显而易见，本发明装置从结构简化和探测器、滤波器数量等方面，能大大降低生产成本。而且，基于差分探测的方式，本发明装置可以实现更快速、更高精度、更高信噪比的探测。
附图说明
图1为本发明的检测装置的原理示意图；
图2为气室内反射腔的示意图；
图3为多波长脉冲序列发生模块发出的一种时序信号。
附图标记：
1‐多波长脉冲序列发生模块
2‐第一探测单元
3‐第二探测单元
4‐气室主体
5‐气室入口组件
6‐气室出口组件
具体实施方式
为使发明的目的、技术方案和优点更加清楚，下面将结合发明中的附图，对发明中的技术方案进行清楚地描述，显然，所描述的实施例是发明一部分实施例，而不是全部的实施例。基于发明中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于发明保护的范围。
实施例1：
如图1所示，本实施例提供了一种快速、高精度、高信噪比复合气体组份、浓度检测装置。并且优选地，其还可以同时检测悬浮颗粒的颗粒度、浓度。本发明的装置包括多波长脉冲序列发生模块1，第一探测单元2，第二探测单元3，气室主体4，气室入口组件5以及气室出口组件6。被测气体从气室入口组件5处进入气室内部，从气室出口组件6处流出。
本实施例中，多波长脉冲序列发生模块1为由脉冲电源与4个不同中心波长QCL激光光源封装组成的模块，中心波长分别对应PM2.5、PM10颗粒物的指纹波长(532nm，640nm)，CO 2的指纹波长(4.26μm)和甲醛的指纹波长(3.56μm)。多个波长激光的时序触发方式如图3所示。本实施例中，多波长脉冲序列发生模块(1)设置于气室最右端，通过气室窗口入射到气室内。
继续参照图1，第一探测单元2设置于气室入口附近，采用对PM2.5、PM10颗粒物的指纹波长(532nm，640nm)响应的光电二极管。用于进行以光散射法进行测量，测量双波长脉冲光特定散射角散射光强及前向散射光强。
第二探测单元3设置于气室出口附近，采用对CO 2的指纹波长(4.26μm)和甲醛的指纹波长(3.56μm)响应的光电二极管，用于以红外光谱吸收法测量多波长脉冲光经气室主模块(4)传播后的光强。
气室主体4可以采用如图2所示结构。该气室符合White型反射式气室特征，由4个曲率半径相同的凹面反射镜组成，光束由气室右下角处的光束入口射入，气室左上角的光束出口出射到第二探测单元上，以此获得更长的光程，从而在CO 2和甲醛含量很少的时候也能检测。
优选的，气室入口组件(5)内壁涂有防尘涂层，用以延长装置使用使用寿命和增加检测精度。另外气室入口组件(5)处的结构符合流体力学原理，使待测气体能在装置内顺畅流动。
优选的，气室出口组件(6)安装有低功耗静音无振动风扇，朝向气室外进行吹风，以使待测样本从气室入口处吸入，能随所需脉冲序列时序运转或连续运转。此外，风扇具有急速运转模式，当装置开机时可以将风扇设置成极速运转模式，以通过风扇的极速运转清洁气室入口组件(5)、气室主体(4)和气室出口组件(6)，延长装置使用寿命。
优选的，信号处理模块包括滤波电路、差分放大电路和STM32L031G6U6单片机芯片。
本实施例中装置的使用过程如下：
1：通过风扇以恒定流速将样品(被测气体)由从气室入口组件(5)处送入，气室出口组件(6)处送出。
2：启动多波长脉冲序列发生模块(1)，使其以重复频率为R，脉冲宽度为τ的脉冲序列的方式，向测试气室中发射根据需要选取的波长的光脉冲，具体而言，依 次将PM2.5、PM10颗粒物的指纹波长(532nm，640nm)的测量光脉冲在气室入口组件(5)末端的入射窗口发射到气室内，并且将CO 2指纹波长(4.26μm)测量光脉冲到气室主体(4)，甲醛指纹波长(3.56μm)的测量光脉冲到气室主体(4)(本实施例中，所发射光脉冲为上述四个指纹波长的光，本领域技术人员可以增加序列中波长数目，单次所需测量的气体组分越多，本发明装置的综合成本越低，综合效益越高)，进行测试。单个波长为λ的脉冲在气室内的耗散时间t满足
Figure PCTCN2022099026-appb-000017
3：利用第一探测单元(2)探测散射光信号，以PM2.5、PM10颗粒物的指纹波长(532nm，640nm)脉冲光作为测量光，使用光散射法进行悬浮颗粒物颗粒度及相应浓度的测量(光散射法测量以及散射颗粒物的粒度和浓度计算可以采用现有方法进行)。从脉冲序列中选取光散射法所需测试光(为了更好地示例说明，这里仅为532nm和640nm，但是实际应用中可以选取更多波长)，确定选定波长的散射系数。若测试光波长为λ，出射光强为I 0(λ)，测试光程长度为l，并测量前向散射光强I s||(λ)，可以得到，经过长度为l的散射介质后，对于不同波长下不同散射系数间关系为：
Figure PCTCN2022099026-appb-000018
即为同质散射系数方程，λ a、λ b为两种测量波长。根据此公式，相同散射介质条件下，两两一组，将不同波长测试光分别代入该公式，得到多个同质散射系数方程，构成同质散射系数方程组。该方程组用于提高后续红外光谱法测量的测量精度。
此外，设波长为λ，测得出射光强为I 0(λ)，测试光程长度为l，并测量前向散射光强I s||(λ)可以得到参考散射系数γ(λ)，其值为
Figure PCTCN2022099026-appb-000019
将多个波长测试光的光强结果带入，可以得到多个参考散射系数。同时测量特定散射角下所选取的多波长的侧向散射光强I s⊥(λ)，使用光散射法分析得到悬浮颗粒物颗粒度及相应浓度；
4：利用第二探测单元3探测红外光信号，使用红外光谱检测法进行测量。在红外光谱检测中，对于需要测量的气体组份1、气体组份2、气体组份3···气体组份n，有对应测试波长λ 1、λ 2、λ 3···λ n，对应摩尔分子吸收系数分别为
Figure PCTCN2022099026-appb-000020
Figure PCTCN2022099026-appb-000021
对应所需测得浓度为c 1、c 2、c 3···c n，且测试波长λ 1、λ 2、λ 3···λ n仅与对应气体组份1、气体组份2、气体组份3···气体组份n存在较强吸收，其余组份的吸收可以忽略。设检测光程为L，得到红外光谱测量方程组
Figure PCTCN2022099026-appb-000022
对于本实施例而言，则是以CO2指纹波长(4.26μm)脉冲光和甲醛指纹波长(3.56μm)脉冲光分别作为测量光，使用红外光谱法进行测量，得到红外光谱测量方程，与步骤3得到的方程联立得到方程组；
5：将(5)(7)(8)联立，将测得输入代入方程组中拟合，联立求解；在求解过程中，参考散射系数选择与红外光谱测量中的测量光相近波长的参考散射系数，确定散射项大小。
对于摩尔分子吸收系数较大的(如CO 2气体在4.26μm指纹波长下吸收谱带强度为95.5*10 ‐18cm ‐1)由其确定了散射项的红外光谱测量方程直接得到，对摩尔分子吸收系数较小的(如CO气体在4.67μm指纹波长下吸收谱带强度为9.8*10 ‐18cm ‐1，虽然本实施例中为了简化没有对其进行测量，但实际使用中，通常需要对其进行测量，因此，本发明的涵盖了对其测量的情况)，确定了散射项大小的红外光谱测量方程组采用阶梯差分运算得到准确的气体组份浓度结果，其运算公式如下
Figure PCTCN2022099026-appb-000023
将上述步骤得到的参考散射系数、同质散射系数方程、红外光谱测量方程组联立，确定散射项大小，采用阶梯差分得到准确的气体组分浓度。
实施例2：
本实施例中的复合气体组份、浓度及悬浮颗粒的颗粒度、浓度的检测装置与实施例1基本相同。具体而言，该装置包括多波长脉冲序列发生模块(1)，第一探测单元(2)，第二探测单元(3)，气室主体(4)，气室入口组件(5)，气室出口组件(6)。
不过，本实施例中，多波长脉冲序列发生模块(1)为由脉冲电源与2个不同中心波长的半导体激光光源和3个不同中心波长红外LED光源封装组成的模块，中心波长分别对应PM2.5、PM10颗粒物的指纹波长(双波长)，CO的指纹波长(4.67μm)，SO 2(7.26μm)指纹波长和甲烷的指纹波长。
第一探测单元(2)为对PM2.5、PM10颗粒物的指纹波长(双波长)响应的CCD器件。用于光散射法测量，测量双波长脉冲光特定散射角散射光强及前向散射光强。
第二探测单元(3)为对CO的指纹波长、SO 2的指纹波长和甲烷的指纹波长响应的光敏电阻，用于红外光谱吸收法测量多波长脉冲光经气室主模块(4)传播后的光强。
气室主体(4)，符合Chernin型反射式气室特征，由3个曲率半径相同的凹面反射镜组成，以此获得较长的光程，从而在CO、SO 2和甲烷含量很少的时候也能检测。
本实施例中装置的操作步骤为：
1.通过风扇以恒定流速将样品(被测气体)由从气室入口(5)处送入，气室出口(6)处送出；
2.以脉冲序列的形式，依次将PM2.5、PM10颗粒物的指纹波长(双波长)的测量光脉冲发射到气室入口组件(5)末端(第一探测单元可以在(5)末端也可以集成到气室(4)内部)，CO指纹波长测量光脉冲到气室主 体(4)，SO 2指纹波长测量光脉冲到气室主体(4)，甲烷指纹波长的测量光脉冲到气室主体(4)。
3.以PM2.5、PM10颗粒物的指纹波长(双波长)脉冲光作为测量光，使用光散射法进行测量，得到悬浮颗粒物颗粒度及相应浓度，同时得到参考散射系数。
4.对两个参考系散射系数进行拟合，对散射项进行修正并得到同质散射系数方程。
5.以CO指纹波长脉冲光作为测量光，使用红外光谱法进行测量，得到红外光谱测量方程。
6.以SO 2指纹波长脉冲光作为测量光，使用红外光谱法进行测量，得到红外光谱测量方程。
7.以甲烷指纹波长脉冲光最为测量光，使用使用红外光谱法进行测量，得到红外光谱测量方程，与步骤4，步骤5得到的方程联立得到方程组。将上述步骤得到的参考散射系数、同质散射系数方程、红外光谱测量方程组联立，确定散射项大小，采用阶梯差分得到准确的气体组分浓度。
实施例3：
本实施例的检测装置与实施例1基本相同，包括多波长脉冲序列发生模块(1)，第一探测单元(2)，第二探测单元(3)，气室主体(4)，气室入口组件(5)，气室出口组件(6)。
不过，本实施例中，多波长脉冲序列发生模块(1)为由脉冲电源与2个不同中心波长的固体激光光源和3个不同中心波长QCL激光光源封装组成的模块，中心波长分别对应PM2.5、PM10颗粒物的指纹波长(双波长)，CO 2的指纹波长，SO 2指纹波长和甲烷的指纹波长。
优选的，第一探测单元(2)为对PM2.5、PM10颗粒物的指纹波长(双波长)响应的CMOS器件。用于光散射法测量，测量双波长脉冲光特定散射角散射光强及前向散射光强。
第二探测单元(3)为对CO 2的指纹波长，SO 2的指纹波长和甲醛的指纹波长响应的热释电探测器，用于红外光谱吸收法测量多波长脉冲光经气室主模块(4)传播后的光强。
气室主体(4)，符合直射式气室特征，具有结构简单，成本低的特点。
本实施例中装置的操作步骤为：
1.通过风扇以恒定流速将样品(被测气体)由从气室入口(5)处送入，气室出口(6)处送出；
2.以脉冲序列的形式，依次将PM2.5、PM10颗粒物的指纹波长(双波长)的测量光脉冲发射到气室入口组件(5)末端，CO 2指纹波长测量光脉冲到气室主体(4)，SO 2指纹波长测量光脉冲到气室主体(4)，甲烷指纹波长的测量光脉冲到气室主体(4)。
3.以PM2.5、PM10颗粒物的指纹波长(双波长)脉冲光作为测量光，使用光散射法进行测量，得到悬浮颗粒物颗粒度及相应浓度，同时得到参考散射系数。
4.对两个参考系散射系数进行拟合对散射项进行修正，并得到同质散射系数方程。
5.以CO 2指纹波长脉冲光作为测量光，使用红外光谱法进行测量，得到红外光谱测量方程。
6.以SO 2指纹波长脉冲光作为测量光，使用红外光谱法进行测量，得到红外光谱测量方程。
7.以甲醛指纹波长脉冲光最为测量光，使用使用红外光谱法进行测量，得到红外光谱测量方程，与步骤4，步骤5得到的方程联立得到方程组。
8.将上述步骤得到的参考散射系数、同质散射系数方程、红外光谱测量方程组联立，确定散射项大小，采用阶梯差分得到准确的气体组分浓度。
实施例4：
本实施例的检测装置与实施例基本相同，包括多波长脉冲序列发生模块(1)，第一探测单元(2)，第二探测单元(3)，气室主体(4)，气室入口组件(5)，气室出口组件(6)。
不过，本实施例中，多波长脉冲序列发生模块(1)为由脉冲电源与2个不同中心波长的半导体激光光源和4个不同中心波长红外LED光源封装组成的模块，中心波长分别对应PM2.5、PM10颗粒物的指纹波长(双波长)，CO 2的指纹波长，SO 2的指纹波长，甲醛指纹波长和甲烷(3.31μm)的指纹波长。
第一探测单元(2)为对PM2.5、PM10颗粒物的指纹波长(双波长)响应的光电二极管器件。用于光散射法测量，测量双波长脉冲光特定散射角散射光强及前向散射光强。
第二探测单元(3)为对CO 2的指纹波长，SO 2的指纹波长，甲醛的指纹波长和甲烷的指纹波长响应的光敏电阻，用于红外光谱吸收法测量多波长脉冲光经气室主模块(4)传播后的光强。
气室主体(4)，符合WHITE型反射式气室特征，由4个曲率半径相同的凹面反射镜组成，以此获得较长的光程，从而在CO 2、SO 2、甲醛和甲烷含量很少的时候也能检测。
本实施例中装置的操作步骤为：
1.通过风扇以恒定流速将样品(被测气体)由从气室入口(5)处送入，气室出口(6)处送出；
2.以脉冲序列的形式，依次将PM2.5、PM10颗粒物的指纹波长(双波长)的测量光脉冲发射到气室入口组件(5)末端，CO 2指纹波长测量光脉冲到气室主体(4)，SO 2指纹波长测量光脉冲到气室主体(4)，甲醛指纹波长的测量光脉冲到气室主体(4)，甲烷指纹波长的测量光脉冲到气室主体(4)。
3.以PM2.5、PM10颗粒物的指纹波长(双波长)脉冲光作为测量光，使用光散射法进行测量，得到悬浮颗粒物颗粒度及相应浓度，同时得到参考散射系数。
4.对两个参考系散射系数进行拟合对散射项进行修正，并得到修正系数和同质散射系数方程。
5.以CO 2指纹波长脉冲光作为测量光，使用红外光谱法进行测量，得到红外光谱测量方程。
6.以SO 2指纹波长脉冲光作为测量光，使用红外光谱法进行测量，得到红 外光谱测量方程。
7.以甲醛指纹波长脉冲光作为测量光，使用红外光谱法进行测量，得到红外光谱测量方程。
8.以甲烷指纹波长脉冲光最为测量光，使用使用红外光谱法进行测量，得到红外光谱测量方程，与步骤4，步骤5，步骤6得到的方程联立得到方程组。
将上述步骤得到的参考散射系数、同质散射系数方程、红外光谱测量方程组联立，确定散射项大小，采用阶梯差分得到准确的气体组分浓度。
在一些优选实施例中，所述装置包括探测如下气体的功能：PM2.5颗粒物、PM10颗粒物、甲醛、甲烷、CO 2、SO 2、CO、NO 2、O 3、氨气等等。
在一些优选实施例中，所述装置还包括温湿度探测、补偿功能。
在一些优选实施例中，所述装置上设置有通讯接口。
在一些优选实施例中，所述装置的供电方式为外部直流供电或电池供电。
在一些优选实施例中，所述装置可以作为微型传感器集成到空调系统、新风系统等系统中。

Claims (10)

  1. 一种用于复合气体的综合检测装置，其特征在于，所述综合检测装置包括多波长脉冲序列发生模块、第一探测单元、第二探测单元、气室以及信号处理模块，所述多波长脉冲序列发生模块用于向所述气室进行多波长脉冲序列发射，所述脉冲序列包括用于散射法测量的第一脉冲序列和用于红外光谱法测量的第二脉冲序列；
    所述第一探测单元设置于所述气室主体的第一位置处，用于测量所述第一脉冲序列的散射光；
    所述第二探测单元设置于所述气室主体的第二位置处，用于测量所述第二脉冲序列的输出光；
    所述信号处理模块用于：基于所述第一脉冲序列的测量光和散射光强度，计算所述气室内物质对于至少一种波长的散射系数作为参考散射系数；对所述参考散射系数进行拟合，确定第一脉冲序列各个波长中，任意两种波长的散射系数关系，构建同质散射系数方程；基于各波长的入射光强和出射光强构建红外光谱测量方程组；并求解由同质散射系数方程以及红外光谱测量方程组构成的联立方程组，确定所述气室内各个气体组份浓度。
  2. 根据权利要求1所述的装置，其特征在于，所述多波长脉冲序列发生模块为下述模块之一：
    (1)由脉冲电源与多个激光光源组成的模块；
    (2)由脉冲电源与多个LED光源组成的模块；
    (3)由脉冲电源、热辐射光源与沿气室壁分布的多个滤光片组成的模块；或者
    (4)由脉冲电源、气体放电光源与沿气室壁分布的多个滤光片组成的模块。
  3. 根据权利要求1所述的装置，其特征在于，所述第一探测单元，位于所述气室入口的一侧，用于光散射法测量，测量第一脉冲序列中多波长脉冲光特定散射角的散射光强及前向散射光强。
  4. 根据权利要求1所述的装置，其特征在于，所述第二探测单元，位于所述气室主体部分的一侧，用于测量第二脉冲序列中多波长脉冲光经气室传播后的光强。
  5. 根据权利要求1所述的装置，其特征在于，
    所述信号处理模块包含滤波电路、差分放大电路和单片机芯片。
  6. 根据权利要求1所述的装置，其特征在于，所述气室包括气室入口组件、其实出口组件及气室主体，三者对所述第一和第二脉冲序列中的多波长脉冲光具有高反射率。
  7. 根据权利要求6所述的装置，其特征在于，所述气室入口组件及气室主体内部相互连接，且内部喷涂有防尘涂层；
    所述气室符合直射式或者White型气室、Herriot型气室或Chernin型气室的特征。
  8. 根据权利要求6所述的装置，其特征在于，所述气室出口组件用于将待测样本从所述气室入口组件处吸入并且通过急速气流清洁所述气室内的各组件。
  9. 根据权利要求1所述的装置，其特征在于，所述信号处理模块采用下述方式进行信号处理：
    (1)计算参考散射系数，所述参考散射系数通过前向散射光强测量得到，其计算公式为：
    Figure PCTCN2022099026-appb-100001
    其中，I s||为前向散射光的光强，I 0为入射光的光强，l为散射光程；
    (2)计算对于不同波长下不同散射系数间关系为：
    Figure PCTCN2022099026-appb-100002
    其中，λ a、λ b为两种测量波长；
    (3)构建红外光谱测量方程组，其表达式为：
    Figure PCTCN2022099026-appb-100003
    其中，I in为输入光强，I out为输出光强，气体浓度为c 1、c 2、c 3…c n，摩尔分子吸收系数分别为
    Figure PCTCN2022099026-appb-100004
    测试波长为λ 1、λ 2、λ 3…λ n，L为红外光谱测量时的光程；
    (4)求解由上述方程构成的联立方程组。
  10. 根据权利要求1所述的装置，其特征在于，当任意气体组分浓度确定后，其他气体组分的浓度计算公式为，
    Figure PCTCN2022099026-appb-100005
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Publication number Priority date Publication date Assignee Title
CN113588585A (zh) * 2021-06-25 2021-11-02 张玉芝 一种用于复合气体组分的快速检测方法
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6055052A (en) * 1998-01-26 2000-04-25 Mie Corporation System for, and method of, monitoring airborne particulate, including particulate of the PM2.5 class
JP2006138727A (ja) * 2004-11-11 2006-06-01 Kyoto Univ 粒子分析装置
CN101059428A (zh) * 2007-05-23 2007-10-24 浙江大学 基于修正卡尔曼滤波理论的气体浓度定量分析仪
US7656526B1 (en) * 2006-07-21 2010-02-02 University Corporation For Atmospheric Research Lidar system for remote determination of calibrated, absolute aerosol backscatter coefficients
CN109813639A (zh) * 2019-01-07 2019-05-28 东南大学 一种基于红外光调制技术的颗粒物与气体浓度同步测量装置及其测量方法
CN113670888A (zh) * 2021-06-25 2021-11-19 张玉芝 一种室内空气中微生物及气体组分、颗粒物检测方法
CN113884417A (zh) * 2021-06-25 2022-01-04 张玉芝 一种用于复合气体的综合检测装置

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3310390B2 (ja) * 1993-06-10 2002-08-05 浜松ホトニクス株式会社 散乱媒質内吸光物質の濃度測定方法および装置
CN100451621C (zh) * 2005-12-02 2009-01-14 中国科学院安徽光学精密机械研究所 高精度前向多角度大气散射测量方法
CN203616232U (zh) * 2013-12-09 2014-05-28 太原科技大学 一种测量大气颗粒物的平均粒径和浓度的测量装置
CN103728229A (zh) * 2013-12-09 2014-04-16 太原科技大学 测量大气颗粒物的平均粒径和浓度的测量装置及测量方法
US10422745B2 (en) * 2015-06-24 2019-09-24 Hamamatsu Photonics K.K. Scattering absorber measurement device and scattering absorber measurement method
CN106644942A (zh) * 2017-02-22 2017-05-10 中国科学院合肥物质科学研究院 光声吸收池及大气颗粒物多光学参数在线测量装置

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6055052A (en) * 1998-01-26 2000-04-25 Mie Corporation System for, and method of, monitoring airborne particulate, including particulate of the PM2.5 class
JP2006138727A (ja) * 2004-11-11 2006-06-01 Kyoto Univ 粒子分析装置
US7656526B1 (en) * 2006-07-21 2010-02-02 University Corporation For Atmospheric Research Lidar system for remote determination of calibrated, absolute aerosol backscatter coefficients
CN101059428A (zh) * 2007-05-23 2007-10-24 浙江大学 基于修正卡尔曼滤波理论的气体浓度定量分析仪
CN109813639A (zh) * 2019-01-07 2019-05-28 东南大学 一种基于红外光调制技术的颗粒物与气体浓度同步测量装置及其测量方法
CN113670888A (zh) * 2021-06-25 2021-11-19 张玉芝 一种室内空气中微生物及气体组分、颗粒物检测方法
CN113884417A (zh) * 2021-06-25 2022-01-04 张玉芝 一种用于复合气体的综合检测装置

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
SHEN, NING: "Study on the Microbolometer in a Standard CMOS Technology", CHINA DOCTORAL DISSERTATIONS FULL-TEXT DATABASE(ELECTRONIC JOURNAL), INFORMATION & TECHNOLOGY, 1 July 2015 (2015-07-01), pages 1 - 151, XP093017313, [retrieved on 20230124] *

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