CN210051664U - Particle diameter and particle concentration on-line measuring device - Google Patents

Abstract

The utility model discloses an on-line detection device for particle diameter and particle concentration, which comprises a detection chamber and a fixed housing, wherein the detection chamber is provided with a particle collimation acceleration spray head and an air outlet joint, and the gas of the particle collimation acceleration spray head forms a particle airflow beam; install light source and light inlet lens subassembly in the fixed housing, the total light beam that the light source produced passes through light inlet lens subassembly and produces two bundles of detection light beams and intersect in first position and second position with gas flow path respectively, is provided with light outlet lens subassembly and two photoelectric detector on the detection cavity, and two photoelectric detector's light intensity detection range is different, is received by two photoelectric detector after the scattered light of particle scattering passes through light outlet lens subassembly. The online detection device has a wider particle size range, and the detection result is more accurate.

Description

Particle diameter and particle concentration on-line measuring device

Technical Field

The utility model relates to an on-line measuring device for detecting particle diameter and particle concentration still relates to an on-line measuring method simultaneously.

Background

In the atmosphere, pollutants are mostly attached to the surfaces of aerosol particles, the particle size of the aerosol is generally 0.001-100 microns, and it is found that particles with aerodynamic diameters of more than 50 microns cannot enter the respiratory tract of a human body due to gravity, particles with aerodynamic diameters of 10-50 microns can only enter the nasopharynx part, particles with aerodynamic diameters of 2.5-10 microns can usually enter the bronchus, and 80% of particles with aerodynamic diameters of less than 2.5 microns can enter the alveoli of the human body.

The particle size and concentration of particles in gas can be detected on line widely, such as: monitoring of ambient air particulate matter (PM10/PM 2.5); and (4) testing the air cleanliness of the industrial clean room. The light scattering particle counter, as a traditional on-line detection instrument in this aspect, has the advantages of being fast, high in sensitivity, small in size and low in maintenance requirement, and the defects of the light scattering particle counter are obvious: the accuracy of the given particle size distribution result depends on the calibration of the particle size-signal intensity curve, and is greatly influenced by the change of particle components (namely, calibration is needed for various particles, and users sometimes cannot accept the curve), and more troublesome is that even if only a single material particle is measured, multivalue can occur in the particle size interval of 0.5-5 μm, that is, the same signal intensity can correspond to a plurality of particle sizes, and the principle of the light scattering particle counter is that the intensity of scattered light is detected after incident light is scattered by the dust particles, but the shape of the dust particles is different and not necessarily spherical, so that the irradiation surface irradiated by the incident light on the dust particles is different, the signal intensity of the same scattered light is only the same as the irradiation surface, but in the case that the irradiation surface is the same, the shape of the dust particles is different, the actual particle size of the particles is different, but the detection result is the same, therefore, the conventional light scattering detection results in certain particle size intervals are not very accurate.

In addition, there is an apparatus based on single particle scattered light signal analysis (such as 3321 model particle size spectrometer by TSI company), which determines the aerodynamic diameter of a particle by measuring the flow velocity of the particle in the air flow, compared with a general light scattering particle counter, this method needs to calibrate the aerodynamic diameter-particle flow velocity curve of the particle, is less affected by the change of the particle composition, and has no problem of multivalueness.

However, the range of particle size measurement of the above two analytical instruments is limited, and the dynamic range of response of a single photodetector does not exceed 4000: 1, when the particle size is less than 0.1. mu.m, the scattered light signal is easily buried by the scattered light signal of the surrounding molecules, and the minimum measurable particle size of the light scattering particle counter is generally 0.1 to 0.2. mu.m. The lower limit of particle size measurement of the particle aerodynamic diameter measuring instrument is mainly determined by the followability of the particles and the air flow, and the general range is 0.5-20 μm.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the technical problem that will solve is: provided is an on-line particle size and particle concentration detection device which has a wider particle size range and more accurate detection results.

In order to solve the technical problem, the technical scheme of the utility model is that: an online particle size and particle concentration detection device comprises a detection chamber, wherein a particle collimation acceleration spray head and an air outlet joint which are communicated with an inner cavity of the detection chamber are arranged on the detection chamber, an annular zero gas channel and a sample gas channel are arranged on the particle collimation acceleration spray head, the annular zero gas channel wraps the sample gas channel, and the zero gas flowing out of the zero gas channel wraps the sample gas flowing out of the sample gas channel to form a particle gas flow beam;

a fixed cover is arranged on the detection chamber, a light source and a light inlet lens component are arranged in the fixed cover, the total light beam generated by the light source generates two incoming light detection beams through the incoming light lens assembly, the two incoming light detection beams are intersected with the particle gas flow beam, the two incoming light detection beams are defined as a first detection light beam and a second detection light beam, the position where the first detection light beam is intersected with the gas flow path is a first position, the position where the second detection light beam is intersected with the gas flow path is a second position, the first position is located at the upstream of the second position, and the first position and the second position are separated by a certain distance, the detection chamber is provided with a light-emitting lens component and two photodetectors for detecting scattered light signals, and the light intensity detection ranges of the two photoelectric detectors are different, and the scattered light scattered by the particles is received by the two photoelectric detectors after passing through the light outlet lens assembly.

As a preferable scheme, the light inlet lens assembly includes a beam splitter, a correction lens and a light inlet beam splitter, which are sequentially arranged along the traveling direction of the total light beam, a reference light detector matched with the beam splitter is arranged on the fixed housing, and a part of light reflected by the beam splitter of the total light beam is received by the reference light detector.

As a preferred scheme, the light-emitting lens assembly is a light-emitting spectroscope, the two photodetectors are arranged at two focuses of the light-emitting spectroscope, and the light scattered by the particles of the first detection light beam and the second detection light beam is received by the two photodetectors after passing through the light-emitting spectroscope.

As a preferable scheme, an aspheric ellipsoidal reflector is arranged in the detection chamber, the aspheric ellipsoidal reflector has a pair of conjugate points, the first detection light beam and the second detection light beam are perpendicular to the particle airflow beam, the first position and the second position are respectively the upstream and the downstream of one conjugate point and are close to the conjugate point, the other conjugate point is arranged on the incident surface of the light-emitting spectroscope, and scattered light scattered by particles in the particle airflow beam is reflected by the aspheric ellipsoidal reflector, focused on the incident surface of the light-emitting spectroscope, and then is received by the two photodetectors after being split by the light-emitting spectroscope.

Preferably, the detection chamber is provided with an optical trap at the opposite side of the light-entering spectroscope.

Preferably, the light source is a laser or LED light source.

After the technical scheme is adopted, the utility model discloses an effect is: because the particle collimation accelerating sprayer and the air outlet joint which are communicated with the inner cavity of the detection chamber are arranged on the detection chamber, the particle collimation accelerating spray head is provided with an annular zero gas channel and a sample gas channel, the annular zero gas channel wraps the sample gas channel, the zero gas flowing out from the zero gas channel wraps the sample gas flowing out from the sample gas channel to form a particle gas flow beam, so that the flowing route of the sample gas is a straight line under the protection of the zero gas, and the dissipation of dust particles is avoided, the dust particles pass through the first position and the second position one by one after being accelerated, then the total light beam generated by the light source generates a first detection light beam and a second detection light beam through the light inlet lens component to irradiate a first position and a second position respectively, the dust particles form scattered light through the first position and the second position, scattered light generated at the first position and scattered light generated at the second position are detected by the two photodetectors after being split by the light-emitting lens assembly. The two photoelectric detectors have different light intensity detection ranges, so that the two photoelectric detectors can detect the light signal intensity of the light scattering particle size to obtain the particle size of the particle, and can detect the aerodynamic particle size according to the time difference of the scattered light signals, and the problem of multivalue is avoided, so that the two results can be verified mutually, the result is more accurate, and when the flow velocity of the particle flowing through the particle airflow beam is close to the flow velocity of the airflow and the scattered light signal intensity of the particle is higher than the scattered light signal of molecules around the particle, the light scattering particle size of the particle is calculated by the scattered light signal intensity detected by the corresponding photoelectric detector with higher sensitivity and smaller value, so that the detection of smaller particle size can be adapted; when the particle size is too large, the photoelectric detector with a smaller value detects that the intensity of the scattered light signal is saturated, and the particle size of the particle is calculated according to the intensity of the scattered light signal detected by the photoelectric detector with the lowest sensitivity; therefore, the particle size range of the online detection device can be further enlarged, and the particle size detection requirement in the range of 0.2-50 mu m can be met.

And because the light inlet lens component comprises a light splitter, a correcting lens and a light inlet spectroscope which are sequentially arranged along the advancing direction of the total light beam, the fixed housing is provided with a reference light detector matched with the light splitter, and part of light reflected by the total light beam through the light splitter is received by the reference light detector, the power of the light source can be ensured to be in the state of initial calibration during zero calibration operation, and the influence of inaccurate zero calibration on the accuracy of a detection result caused by the loss of the power of the light source is avoided.

And because the detection chamber is internally provided with the aspheric ellipsoidal reflector which is provided with a pair of conjugate points, the first detection beam and the second detection beam are vertical to the particle airflow beam, the first position and the second position are respectively the upstream and the downstream of one conjugate point and are close to the conjugate point, the other conjugate point is arranged on the incident surface of the light-emitting spectroscope, the scattered light scattered by the particles in the particle airflow beam is focused on the incident surface of the light-emitting spectroscope after being reflected by the aspheric ellipsoidal reflector, and then is received by the two photoelectric detectors after being split by the light-emitting spectroscope, the scattered light of the particles is reflected by the aspheric ellipsoidal reflector after scattering and then enters the incident surface of the light-emitting spectroscope, and finally is split again to be detected by the two photoelectric detectors, so that the enhancement of optical signals is realized, and the detection of the photoelectric detectors is more convenient.

And because the light trap is arranged on the opposite side of the light-entering spectroscope on the detection chamber, the light trap can absorb redundant light rays, and interference is reduced.

In addition, the utility model also discloses an online detection method of particle diameter and particle concentration, which uses the online detection device, the sampled sample gas and clean zero gas respectively pass through the sample gas channel and the zero gas channel to form particle airflow beams which enter the detection chamber, and the clean zero gas wraps the sample gas to form a protective gas curtain; the total light beam generated by the light source generates a first detection light beam and a second detection light beam through the light inlet lens component, the first detection light beam and the second detection light beam respectively intersect with the flow path of the particle airflow beam at a first position and a second position, the first detection light beam and the second detection light beam form two beams of scattered light emitted from different positions after passing through the first position and the second position by particles in the particle airflow beam, and two photoelectric detectors respectively generate a scattered light signal; setting two photodetectors as a photodetector A and a photodetector B respectively, wherein the light intensity detection range of the photodetector A is [ A1, A2], the light intensity detection range of the photodetector B is [ B1, B2], A1 is not equal to B1, and A2 is not equal to B2;

s1, when the flow velocity of the particles flowing through the particle airflow is close to the airflow flow velocity and the scattered light signal intensity of the particles is higher than that of the molecules around the particles; calculating the particle size of the particle by the intensity of the scattered light signal detected by the photodetector with the smaller value among A1 and B1;

s2, when the photoelectric detector corresponding to the small value in A1 and B1 detects that the intensity of the scattered light signal is close to saturation, calculating the particle size of the particle according to the intensity of the scattered light signal detected by the photoelectric detector with the large value in A2 and B2;

s3, when the ratio of the particle flow velocity to the airflow flow velocity is lower than a certain threshold value C and the two photoelectric detectors detect that the scattered light signals are far away from saturation, the two photoelectric detectors can detect the scattered light generated at the first position and the second position in sequence and form pulse signals in sequence, and the flight time of the corresponding particles passing through two adjacent light beams is obtained according to the time difference of each group of pulse signals; and comparing the flight time of the detected particles with a flight time table of the particles with standard particle sizes, which is measured in advance, so as to obtain the aerodynamic diameter Dp of each particle in the ambient air sample gas.

Preferably, the on-line detection method further includes a zero calibration method of the light source, wherein a part of a total light beam generated by the light source enters the light-emitting lens assembly, another part of the light beam is reflected by the light splitter to form reflected light and is received by the reference light detector, when the initial state is calibrated, the sample gas channel and the zero gas channel both pass through zero gas, a signal detected by the reference light detector is defined as a standard reference light signal intensity, the corresponding power intensity of the light source is a standard power intensity, a concentration value corresponding to the detected light signal intensity of the photoelectric detector at this time is calibrated to be 0, when the light source is used for a period of time, the power of the light source is adjusted, so that a light intensity signal detected by the reference light detector reaches the standard reference light signal intensity, and then the two photoelectric detectors are adjusted to zero calibration.

Preferably, the online detection method further comprises a signal enhancement method, wherein the scattered light is reflected by an aspheric ellipsoidal reflector arranged in the detection chamber, the first detection light beam and the second detection light beam are perpendicular to the particle gas flow beam, the first position and the second position are respectively the upstream and the downstream of one conjugate point and are close to the conjugate point, the particles generate the scattered light when the particles are successively arranged at the first position and the second position, and the scattered light is reflected by the aspheric ellipsoidal reflector, divided into two beams by the light-emitting spectroscope and received by the two photodetectors.

After the technical scheme is adopted, the utility model discloses an effect is: the online detection method utilizes the first detection light and the second detection light to detect two positions, and then the detection is carried out by two photoelectric detectors with different particle size ranges after passing through the light-emitting lens group, so that not only can the aerodynamic particle size be detected, but also the light scattering particle size can be detected, and the aerodynamic particle size or the light scattering particle size can be selected to be used as the detection data of the particles according to different characteristics of the particles, so that the detection result is more accurate, the particle size range without multivalued detection is larger, and the particle size detection requirement in the range of 0.2-50 mu m can be met.

Drawings

The present invention will be further explained with reference to the drawings and examples.

Fig. 1 is an external structural view of an embodiment of the present invention;

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1;

FIG. 3 is a right side view of FIG. 1;

FIG. 4 is a cross-sectional view taken along line B-B of FIG. 3;

FIG. 5 is a schematic view of FIG. 1 rotated 90 counterclockwise;

FIG. 6 is a cross-sectional view taken along line C-C of FIG. 5;

in the drawings: 1. a detection chamber; 2. fixing the housing; 3. particle collimation accelerating spray heads; 4. an air outlet joint; 5. a sample gas channel; 6. a zero gas channel; 7. a stream of particles; 8. an aspheric ellipsoidal reflector; 9. a light trap; 10. a light source; 11. a light splitter; 12. a corrective lens; 13. an incoming light beam splitter; 14. a first position; 15. a second position; 16. a light-emitting spectroscope; 17. a photodetector A; 18. a photodetector B; 19. a reference light detector.

Detailed Description

The present invention will be described in further detail with reference to the following examples.

As shown in fig. 1 to 6, an online particle size and particle concentration detection apparatus includes adetection chamber 1, thedetection chamber 1 is provided with a particlecollimation acceleration nozzle 3 and anair outlet joint 4 which are communicated with an inner cavity of thedetection chamber 1, the particlecollimation acceleration nozzle 3 is provided with an annularzero gas channel 6 and asample gas channel 5, the annularzero gas channel 6 wraps thesample gas channel 5, and the zero gas flowing out from the zerogas channel 6 wraps the sample gas flowing out from thesample gas channel 5 to form a particlegas flow bundle 7; the zero gas is clean air, the sample gas is sampling gas in the environment, and the flow power of the sample gas can be provided by using the sampling pump. After the sample gas is accelerated by the particlecollimation acceleration nozzle 3, particles in the sample gas pass through the particlegas flow beam 7 one by one, and are protected by an external zero gas curtain and can only run in a straight line, and the gas is finally discharged from thegas outlet joint 4.

Thedetection chamber 1 is provided with afixed cover casing 2, alight source 10 and a light inlet lens component are arranged in thefixed cover casing 2, and thelight source 10 is a laser or anLED light source 10. The total light beam generated by thelight source 10 generates two light incoming detection light beams through the light incoming lens assembly, the light incoming lens assembly comprises alight splitter 11, a correctinglens 12 and a lightincoming light splitter 13 which are sequentially arranged along the traveling direction of the total light beam, areference light detector 19 matched with thelight splitter 11 is arranged on thefixed housing 2, and a part of light reflected by thelight splitter 11 of the total light beam is received by thereference light detector 19. Thereference light detector 19 is also actually a photo detector.

The two incoming light detection beams intersect the particlegas flow beam 7, and the two incoming light detection beams are defined as a first detection beam and a second detection beam, the position where the first detection beam intersects the gas flow path is afirst position 14, the position where the second detection beam intersects the gas flow path is asecond position 15, thefirst position 14 is located upstream of thesecond position 15, and thefirst position 14 and thesecond position 15 are at a distance, wherein thefirst position 14 and thesecond position 15 are actually the focal points of the first detection beam and the second detection beam of theentrance beam splitter 13. Thedetection chamber 1 is provided with a light-emitting lens assembly and two photodetectors for detecting scattered light signals, the light intensity detection ranges of the two photodetectors are different, and the scattered light scattered by the particles is received by the two photodetectors after passing through the light-emitting lens assembly.

The light-emitting lens assembly is a light-emittingspectroscope 16, the two photodetectors are arranged at two focuses of the light-emittingspectroscope 16, and light scattered by the particles of the first detection light beam and the second detection light beam is received by the two photodetectors after passing through the light-emittingspectroscope 16. An asphericellipsoidal reflector 8 is arranged in thedetection chamber 1, the asphericellipsoidal reflector 8 is provided with a pair of conjugate points, a first detection light beam and a second detection light beam are perpendicular to theparticle airflow beam 7, afirst position 14 and asecond position 15 are respectively the upstream and the downstream of one conjugate point and are close to the conjugate point, the other conjugate point is arranged on the incident surface of the light-emittingspectroscope 16, scattered light scattered by particles in theparticle airflow beam 7 is focused on the incident surface of the light-emittingspectroscope 16 after being reflected by the asphericellipsoidal reflector 8, and is received by two photoelectric detectors after being dispersed by the light-emittingspectroscope 16. The asphericellipsoidal reflector 8 is characterized in that a light beam emitted from one conjugate point is reflected by the asphericellipsoidal reflector 8 and then necessarily passes through the other conjugate point, and thefirst position 14 and thesecond position 15 are close to one conjugate point, so that the generated scattered light is scattered by the asphericellipsoidal reflector 8 and then emitted to the other conjugate point and the periphery, and the incident surface of the light-emittingbeam splitter 16 has a certain width, so that the scattered light can be accurately received, and the intensity is enhanced.

The light trap 9 is arranged on thedetection chamber 1 and located at the opposite side of the lightincoming spectroscope 13, so that redundant light can be absorbed, and interference is reduced.

The embodiment of the utility model also discloses a particle diameter and particle concentration on-line measuring method, this on-line measuring method has used the on-line measuring device, and the sample gas of sampling and clean zero gas form particle air current bundle 7 respectively through sample gas passageway 5 and zero gas passageway 6 and flow into in detecting cavity 1, and clean zero gas wraps up sample gas and forms the protection air curtain; a total light beam generated by a light source 10 passes through a light inlet lens assembly to generate a first detection light beam and a second detection light beam which intersect with a flow path of the particle airflow beam at a first position 14 and a second position 15 respectively, particles flying at different speeds in the particle airflow beam 7 of the first detection light beam and the second detection light beam form two scattered light beams from different positions after passing through the first position 14 and the second position 15, and two photoelectric detectors generate a scattered light signal respectively; setting two photodetectors as a photodetector A17 and a photodetector B18, respectively, wherein the light intensity detection range of the photodetector A17 is [ A1, A2], the light intensity detection range of the photodetector B18 is [ B1, B2], A1 is not equal to B1, and A2 is not equal to B2;

s1, when the flow velocity of the particles flowing through the particlegas flow beam 7 is close to the flow velocity of the gas flow and the intensity of the scattered light signals of the particles is higher than the scattered light signals of the molecules around the particles; calculating the particle size of the particles according to the intensity of the scattered light signals detected by the corresponding photodetectors with smaller values in A1 and B1, so that the lower limit of the particle size range can be obtained compared with that of an aerodynamic diameter measuring instrument;

s2, when the photoelectric detector corresponding to the small value in A1 and B1 detects that the intensity of the scattered light signal is close to saturation, calculating the particle size of the particle according to the intensity of the scattered light signal detected by the photoelectric detector with the large value in A2 and B2;

s3, when the ratio of the particle flow velocity to the airflow flow velocity is lower than a certain threshold value C and the two photoelectric detectors detect that the scattered light signals are far away from saturation, the two photoelectric detectors can detect the scattered light generated at thefirst position 14 and thesecond position 15 in sequence and form pulse signals in sequence, and the flight time of the corresponding particles passing through two adjacent light beams is obtained according to the time difference of each group of pulse signals; and comparing the flight time of the detected particles with a flight time table of the particles with standard particle diameters measured in advance to obtain the aerodynamic diameter Dp of each particle in the ambient air sample gas, wherein the particle diameter and the concentration of the particles are based on the aerodynamic particle diameter, and the related information of the material of the particles can be determined by combining the mass concentration of the calibration particles, the aerodynamic particle diameter of the particles and the scattered light signal intensity of the particles, so that the uncertainty of measurement based on the light scattering particle counter principle in other particle diameter sections is reduced. Combining the aerodynamic diameter Dp with the particle concentration of particles with different particle diameters to obtain and display a particle concentration map with different particle diameters, converting the measured aerodynamic diameter Dp of different particles into volume, and multiplying the volume by the average particle density rho to obtain the mass of the particles in the range of PM0.2-PM50, wherein the aerodynamic diameter Dp is in one-to-one correspondence with the mass of the particles; and multiplying the result of the multiplication of the particle mass and the particle concentration by a correction factor K to obtain a mass concentration spectrogram, summing the mass concentrations of the single particles with the diameters less than 2.5 micrometers to obtain PM2.5, summing the mass concentrations of the single particles with the diameters less than 10 micrometers to obtain PM10, and arranging a screen display on an online detection device for displaying and outputting PM2.5 andPM 10. The processing procedures are realized by PLC.

The on-line detection method also comprises a zero calibration method of thelight source 10, wherein one part of a total light beam generated by thelight source 10 enters the light-emitting lens assembly, the other part of the light beam is reflected by thelight splitter 11 to form reflected light and is received by thereference light detector 19, when the initial state is calibrated, thesample gas channel 5 and the zerogas channel 6 both pass through zero gas, a signal detected by thereference light detector 19 at the moment is defined as the standard reference light signal intensity, the corresponding power intensity of thelight source 10 is the standard power intensity, the concentration value corresponding to the light signal intensity detected by the photoelectric detector at the moment is calibrated to be 0, when thelight source 10 is used for a period of time, the power of thelight source 10 is attenuated, the power of thelight source 10 is adjusted at the moment, so that the light intensity signal detected by thereference light detector 19 reaches the standard reference light signal intensity, and then.

The online detection method further comprises a signal enhancement method, wherein scattered light is reflected by an asphericellipsoidal reflector 8 arranged in thedetection chamber 1, a first detection light beam and a second detection light beam are perpendicular to the particlegas flow beam 7, afirst position 14 and asecond position 15 are respectively the upstream and the downstream of one conjugate point and are close to the conjugate point, the particles generate the scattered light when the particles are successively arranged at thefirst position 14 and thesecond position 15, and the scattered light is reflected by the asphericellipsoidal reflector 8, is divided into two light beams by a light-emittingspectroscope 16 and then is received by two photoelectric detectors.

The above-mentioned embodiments are only descriptions of the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention, and all modifications and changes made by the technical solution of the present invention should fall within the protection scope defined by the claims of the present invention on the basis of not departing from the spirit of the present invention.

Claims (6)

1. The utility model provides a particle diameter and particle concentration on-line measuring device which characterized in that: the particle collimation accelerating device comprises a detection chamber, wherein a particle collimation accelerating spray head and an air outlet joint which are communicated with an inner cavity of the detection chamber are arranged on the detection chamber, an annular zero gas channel and a sample gas channel are arranged on the particle collimation accelerating spray head, the sample gas channel is wrapped by the annular zero gas channel, and the sample gas flowing out from the sample gas channel is wrapped by the zero gas flowing out from the zero gas channel to form a particle gas flow beam;

a fixed cover is arranged on the detection chamber, a light source and a light inlet lens component are arranged in the fixed cover, the total light beam generated by the light source generates two incoming light detection beams through the incoming light lens assembly, the two incoming light detection beams are intersected with the particle gas flow beam, the two incoming light detection beams are defined as a first detection light beam and a second detection light beam, the position where the first detection light beam is intersected with the gas flow path is a first position, the position where the second detection light beam is intersected with the gas flow path is a second position, the first position is located at the upstream of the second position, and the first position and the second position are separated by a certain distance, the detection chamber is provided with a light-emitting lens component and two photodetectors for detecting scattered light signals, and the light intensity detection ranges of the two photoelectric detectors are different, and the scattered light scattered by the particles is received by the two photoelectric detectors after passing through the light outlet lens assembly.

2. The on-line detection device for particle size and particle concentration according to claim 1, wherein: the light inlet lens assembly comprises a light splitter, a correcting lens and a light inlet light splitter, the correcting lens and the light inlet light splitter are sequentially arranged along the advancing direction of the total light beam, a reference light detector matched with the light splitter is arranged on the fixed housing, and a part of light of the total light beam reflected by the light splitter is received by the reference light detector.

3. The on-line detection device for particle size and particle concentration according to claim 2, wherein: the light-emitting lens assembly is a light-emitting spectroscope, the two photoelectric detectors are arranged on two focuses of the light-emitting spectroscope, and the light scattered by the particles of the first detection light beam and the second detection light beam is received by the two photoelectric detectors after passing through the light-emitting spectroscope.

4. The on-line detection device for particle size and particle concentration according to claim 3, wherein: an aspheric ellipsoidal reflector is arranged in the detection chamber and provided with a pair of conjugate points, a first detection light beam and a second detection light beam are perpendicular to the particle airflow beams, the first position and the second position are respectively the upstream and the downstream of one conjugate point and are close to the conjugate point, the other conjugate point is arranged on the incident surface of the light-emitting spectroscope, and scattered light scattered by particles in the particle airflow beams is focused on the incident surface of the light-emitting spectroscope after being reflected by the aspheric ellipsoidal reflector and is received by two photoelectric detectors after being dispersed by the light-emitting spectroscope.

5. The on-line detection device for particle size and particle concentration according to claim 4, wherein: and a light trap is arranged on the detection chamber and positioned at the opposite side of the light incoming spectroscope.

6. The on-line detection device for particle size and particle concentration according to claim 5, wherein: the light source is a laser or an LED light source.

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