Flue gas particulate matter detection device and flue gas particulate matter detection system

Abstract

The present invention discloses a smoke particle detection device and a smoke particle detection system. The smoke particle detection device includes: a measuring chamber body having a smoke inlet and a smoke outlet, the smoke inlet and the smoke outlet being connected to form a ventilation duct; a laser incident module for emitting a Gaussian beam; a first detection channel connected to the ventilation duct, the first detection channel being arranged opposite the laser incident module, the first detection channel detecting the concentration of group particles in the ventilation duct based on the scattered light of the Gaussian beam by the group particles in the ventilation duct, and outputting a group particle concentration detection signal; a second detection channel connected to the ventilation duct, the second detection channel being arranged at an angle to the laser incident module, the second detection channel detecting the concentration of single particles in the ventilation duct based on the scattered light of the Gaussian beam by the single particles in the ventilation duct, and outputting a single particle concentration detection signal. The present invention aims to solve the problem of being unable to accurately monitor particulate matter in different concentration ranges.

Description

Technical Field

[0001] The present invention relates to the field of smoke particle detection, and in particular to a smoke particle detection device and a smoke particle detection system. Background Art

[0002] Flue gas particulate matter refers to solid or liquid particles in exhaust gases emitted by stationary pollution sources. Flue gas particulate matter is typically discharged into the atmosphere along with the exhaust gas, directly impacting ambient air quality. Online monitoring equipment for flue gas particulate matter concentration is typically installed at exhaust outlets to provide real-time monitoring of flue gas particulate matter emission concentrations.

[0003] Both the backscattering and forward scattering smoke monitors monitor the concentration of particulate matter based on the principle of light scattering by particulate matter groups. Backscattering smoke monitors are generally suitable for emission concentrations exceeding 30mg / m 3 Forward scattering smoke monitors are generally suitable for emission concentrations greater than 5mg / m 3 For medium and high concentration sites; for emission concentrations below 5mg / m 3 In the following scene, the forward light scattering smoke meter has obvious measurement errors due to the weak scattered light signal and insufficient detection signal-to-noise ratio.

[0004] With the continuous improvement of flue gas treatment level, more and more enterprises have reduced the emission concentration to 5mg / m 3 Next, the problem that forward light scattering smoke dust meters can no longer accurately measure low concentrations of particulate matter is becoming increasingly apparent. Summary of the Invention

[0005] The main purpose of the present invention is to provide a smoke particle detection device and a smoke particle detection system, aiming to solve the problem of being unable to accurately monitor particulate matter in different concentration ranges.

[0006] To achieve the above objectives, the present invention provides a smoke particulate matter detection device, comprising:

[0007] a measuring chamber body, the measuring chamber body having a smoke inlet and a smoke outlet, the smoke inlet and the smoke outlet being connected to form a ventilation duct;

[0008] A laser incident module, the laser incident module is arranged on the measurement cavity body, and the laser incident module is used to emit a Gaussian beam;

[0009] a first detection channel, the first detection channel being disposed on the measurement cavity body and in communication with the ventilation duct, the first detection channel being disposed directly opposite the laser incident module, the first detection channel being configured to detect a concentration of swarm particles in the ventilation duct based on light scattered by the Gaussian beam from the swarm particles in the ventilation duct, and outputting a swarm particle concentration detection signal;

[0010] The second detection channel is arranged on the measuring cavity body and is connected to the ventilation duct. The second detection channel is arranged at an angle to the laser incident module. The second detection channel is used to detect the concentration of single particles in the ventilation duct based on the scattered light of the Gaussian beam caused by the single particles in the ventilation duct, and output a single particle concentration detection signal.

[0011] Optionally, the laser incident module includes:

[0012] a laser diode configured to emit a Gaussian beam;

[0013] a first aperture, the first aperture being arranged opposite to the laser diode so that the Gaussian beam becomes a circular divergent shape after passing through the first aperture;

[0014] A first convex lens is provided opposite to the first aperture, and the Gaussian beam is converged by the first convex lens and then output.

[0015] Optionally, the first detection channel includes:

[0016] A light absorbing plate, configured to absorb the Gaussian beam incident directly from the laser incident module;

[0017] a second convex lens, configured to converge scattered light passing through the group of particles and then output the light;

[0018] The second aperture is arranged opposite to the second convex lens, and is used for filtering the scattered light emitted by the second convex lens and then outputting it.

[0019] Optionally, the first detection channel further includes:

[0020] A low-pass photoelectric detection module is connected to the second aperture, and is used to detect the concentration of group particles in the ventilation duct according to the scattered light output by the second aperture, and output a group particle concentration detection signal.

[0021] Optionally, the low-pass photoelectric detection module includes:

[0022] a first light-guiding optical fiber, one end of which is arranged corresponding to the second aperture;

[0023] A low-pass photoelectric conversion circuit, wherein the input end of the low-pass photoelectric conversion circuit is connected to the other end of the first light-guiding optical fiber, the low-pass photoelectric conversion circuit is used to receive the scattered light output by the second aperture through the first light-guiding optical fiber, detect the group particle concentration in the ventilation duct based on the scattered light output by the second aperture, and output a group particle concentration detection signal.

[0024] Optionally, the second detection channel includes:

[0025] a third convex lens, configured to converge scattered light passing through a single particle and then output the light;

[0026] The third aperture is arranged opposite to the third convex lens, and is used for filtering the scattered light emitted by the third convex lens and then outputting it.

[0027] Optionally, the second detection channel further includes:

[0028] A bandpass photoelectric pulse detection module is connected to the third aperture, and is used to detect the single particle concentration in the ventilation duct based on the scattered light output by the third aperture, and output a single particle concentration detection signal.

[0029] Optionally, the bandpass photoelectric pulse detection module includes:

[0030] a second light-guiding optical fiber, one end of which is arranged corresponding to the third aperture;

[0031] a bandpass photoelectric conversion circuit, wherein the input end of the bandpass photoelectric conversion circuit is connected to the other end of the second light-guiding optical fiber, the bandpass photoelectric conversion circuit is used to receive the scattered light output by the third aperture through the second light-guiding optical fiber, detect the single particle concentration in the ventilation duct based on the scattered light output by the third aperture, and output a single particle concentration detection signal.

[0032] The present invention further provides a smoke particle detection system, which includes the smoke particle detection device described above.

[0033] Optionally, the smoke particulate matter detection system further includes:

[0034] An air pump, the outlet of which is connected to the smoke inlet of the smoke particle detection device, and the air pump is used to draw smoke from the smoke inlet into the measuring cavity body of the smoke particle detection device.

[0035] The present invention comprises a flue gas particle detection device comprising a measuring chamber body, a laser incident module, a first detection channel, and a second detection channel. The measuring chamber body has a flue gas inlet and a flue gas outlet, which are connected to form a ventilation duct. The laser incident module can emit a Gaussian beam. The first detection channel is disposed on the measuring chamber body and connected to the ventilation duct, facing the laser incident module. The first detection channel can detect the concentration of group particles in the ventilation duct based on the scattered light of the Gaussian beam from the group particles in the ventilation duct and output a group particle concentration detection signal. The second detection channel is disposed on the measuring chamber body and connected to the ventilation duct, angled relative to the laser incident module. The second detection channel can detect the concentration of single particles in the ventilation duct based on the scattered light of the Gaussian beam from single particles in the ventilation duct and output a single particle concentration detection signal. This solution, through the first and second detection channels, can detect both the group particle concentration and the single particle concentration in flue gas. The present invention aims to address the problem of being unable to accurately monitor particulate matter in different concentration ranges. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0037] Figure 1 This is a front view of an embodiment of a smoke particulate matter detection device of the present invention;

[0038] Figure 2 is a cross-sectional view of an embodiment of a smoke particulate matter detection device of the present invention;

[0039] Figure 3 This is a diagram of the particle group scattering signal captured by the first detection channel in one embodiment of the smoke particulate matter detection device of the present invention;

[0040] Figure 4 This is a diagram of a single particle scattered pulse signal captured by the second detection channel in an embodiment of the smoke particulate matter detection device of the present invention;

[0041] Figure 5 This is a light path diagram of an embodiment of a smoke particulate matter detection device of the present invention.

[0042] Description of Figure Numbers:

[0043] Label name Label name 10 Measuring cavity body 32 Second aperture 20 Laser incident module 33 First light-guiding fiber 21 Laser diodes 40 Second detection channel 22 First aperture 41 The third convex lens 23 First convex lens 42 Third aperture 30 The first detection channel 43 Second light-guiding fiber 31 Second convex lens 34 Light absorbing plate

[0044] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0045] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0046] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0047] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features specified as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0048] The present invention provides a smoke particulate matter detection device.

[0049] Reference Figure 1 In one embodiment, the smoke particulate matter detection device includes:

[0050] The measuring chamber body 10 has a smoke inlet and a smoke outlet, and the smoke inlet and the smoke outlet are connected to form a ventilation duct;

[0051] A laser incident module 20, which is disposed on the measurement cavity body 10 and is used to emit a Gaussian beam;

[0052] a first detection channel 30, which is disposed on the measurement cavity body 10 and communicates with the ventilation duct. The first detection channel 30 is disposed opposite the laser incident module 20. The first detection channel 30 is used to detect the concentration of swarm particles in the ventilation duct based on the scattered light of the Gaussian beam caused by the swarm particles in the ventilation duct, and output a swarm particle concentration detection signal;

[0053] The second detection channel 40 is arranged on the measuring cavity body 10 and is connected to the ventilation duct. The second detection channel 40 is arranged at an angle to the laser incident module 20. The second detection channel 40 is used to detect the concentration of single particles in the ventilation duct based on the scattered light of the Gaussian beam caused by the single particles in the ventilation duct, and output a single particle concentration detection signal.

[0054] In this embodiment, the ventilation duct formed by the smoke inlet and smoke outlet on the measurement chamber body 10 can be straight to facilitate smoke circulation. If it is set to a curved shape, it may affect the detection of smoke particulate matter fog. The direction of the ventilation duct can be perpendicular to the direction of the Gaussian light velocity emitted by the laser incident module 20. This can minimize the possibility of smoke particulate matter contaminating the lens in the smoke particulate matter detection device. When smoke particles in the smoke flow through the Gaussian light beam emitted by the laser incident module 20, they will be scattered. The scattered light is captured by the first detection channel 30 and the second detection channel 40, respectively. The first detection channel 30 and the second detection channel 40 can respectively detect the concentration of group particles and the concentration of single particles. The first detection channel 30 detects the concentration of group particles, and the second detection channel 40 detects the concentration of single particles. The first detection channel 30 has a first photosensitive area. The first photosensitive area is the area where the light receiving area of ​​the first detection channel 30, the Gaussian light beam emitted by the laser incident module 20, and the smoke intersect. By controlling the volume V1 of the first photosensitive area, V1 satisfies:

[0055]

[0056] The first detection channel 30 is set to face the laser incident module 20, so that the particles can pass through the first photosensitive area in the form of particle groups. In this way, the concentration of the group particles in the first photosensitive area can be detected. The detected particle group scattering signal diagram can be referred to Figure 3 .

[0057] The second detection channel 40 has a second photosensitive area, which is the common area where the light receiving area of ​​the second detection channel 40 and the waist of the Gaussian beam emitted by the laser incident module 20 intersect. By controlling the volume V2 of the second photosensitive area, V2 satisfies:

[0058]

[0059] The second detection channel 40 is set at an angle to the laser incident module 20, so that the particles can pass through the second photosensitive area in the form of single particles. In this way, the concentration of single particles in the second photosensitive area can be detected. The detected single particle scattering pulse signal diagram can be referred to Figure 4 .

[0060] It can be understood that the first detection channel can detect the group particle concentration, that is, the particle concentration in the medium and high concentration range; the second detection channel can detect the single particle concentration, that is, the particle concentration in the low concentration range; in this way, the flue gas particle detection device of this scheme can detect particles in different concentration ranges.

[0061] The present invention comprises a flue gas particle detection device comprising a measuring chamber body 10, a laser incident module 20, a first detection channel 30 and a second detection channel 40. The measuring chamber body 10 has a flue gas inlet and a flue gas outlet, which are connected to form a ventilation duct. The laser incident module 20 can emit a Gaussian beam. The first detection channel 30 is arranged on the measuring chamber body 10 and is connected to the ventilation duct. The first detection channel 30 is arranged opposite the laser incident module 20. The first detection channel 30 can detect the concentration of group particles in the ventilation duct based on the scattered light of the Gaussian beam caused by the group particles in the ventilation duct, and output a group particle concentration detection signal. The second detection channel 40 is arranged on the measuring chamber body 10 and is connected to the ventilation duct. The second detection channel 40 is arranged at an angle to the laser incident module 20. The second detection channel 40 can detect the concentration of single particles in the ventilation duct based on the scattered light of the Gaussian beam caused by single particles in the ventilation duct, and output a single particle concentration detection signal. This solution can detect the concentration of group particles and single particles in the smoke through the first detection channel 30 and the second detection channel 40. The present invention aims to solve the problem of being unable to accurately monitor particles in different concentration ranges.

[0062] Reference Figures 1 to 4 In one embodiment, the laser incident module 20 includes:

[0063] a laser diode 21, wherein the laser diode 21 is configured to emit a Gaussian beam;

[0064] a first aperture 22, the first aperture 22 being arranged opposite to the laser diode 21 so that the Gaussian beam becomes a circular divergent shape after passing through the first aperture 22;

[0065] The first convex lens 23 is arranged opposite to the first aperture 22 , and the Gaussian beam is converged by the first convex lens 23 and then output.

[0066] In this embodiment, the laser diode 21 is used to emit a Gaussian beam. Other lasers can also be used to emit a laser beam, and the specific selection can be made according to actual conditions. The first aperture 22 is set opposite the laser diode 21, so that the elliptical divergent Gaussian beam can be transformed into a circular divergent shape after passing through the first aperture 22, which is convenient for measurement. The Gaussian beam is then converged and then diverged through the first convex lens 23 to prevent the beam from being too dispersed, which may affect the measurement results of the particle concentration.

[0067] Reference Figures 1 to 4 In one embodiment, the first detection channel 30 includes:

[0068] A light absorbing plate 34, configured to absorb the Gaussian beam incident directly from the laser incident module;

[0069] A second convex lens 31, which is used to converge the scattered light passing through the group of particles and then output it;

[0070] The second aperture 32 is arranged opposite to the second convex lens 31 , and is used for filtering the scattered light emitted by the second convex lens 31 and outputting the filtered light.

[0071] In this embodiment, the light absorption plate 34 can be used as a light trap to absorb the Gaussian light beam directly incident on the laser module to prevent the direct light beam from being too strong and affecting the detection results; the second convex lens 31 can first converge the scattered light passing through the group of particles and then output it to prevent the light beam from diverging too much and causing inaccurate measurements. The second aperture 32 can be set to correspond to the focus of the second convex lens 31. The second aperture 32 can filter the stray light from the cavity wall and improve the signal-to-noise ratio, so as to facilitate the detection module to detect the Gaussian light beam and obtain the concentration of the group of particles.

[0072] Reference Figures 1 to 4 In one embodiment, the first detection channel 30 further includes:

[0073] A low-pass photoelectric detection module is connected to the second aperture 32 and is used to detect the concentration of group particles in the ventilation duct according to the scattered light output by the second aperture 32 and output a group particle concentration detection signal.

[0074] In this embodiment, the low-pass photoelectric detection module can receive the scattered light output by the second aperture 32, and convert the optical signal into an electrical signal, and then output a group particle concentration detection signal based on the electrical signal. For example, the electrical signal can be a voltage signal or a current signal. The higher the voltage value represented by the voltage signal output by the low-pass photoelectric detection module, the higher the group particle concentration, and the lower the voltage value represented by the voltage signal, the lower the group particle concentration. The specific corresponding relationship can be set according to actual conditions.

[0075] Reference Figures 1 to 4 In one embodiment, the low-pass photoelectric detection module includes:

[0076] A first light-guiding optical fiber 33 , one end of which is arranged corresponding to the second aperture 32 ;

[0077] A low-pass photoelectric conversion circuit, wherein the input end of the low-pass photoelectric conversion circuit is connected to the other end of the first light-guiding optical fiber 33, and the low-pass photoelectric conversion circuit is used to receive the scattered light output by the second aperture 32 through the first light-guiding optical fiber 33, and detect the group particle concentration in the ventilation duct based on the scattered light output by the second aperture 32, and output a group particle concentration detection signal.

[0078] In this embodiment, one end of the first light-guiding optical fiber 33 receives scattered light from the second aperture 32 and outputs it through the other end to a low-pass photoelectric conversion circuit. This bandpass photoelectric conversion circuit may include a photoelectric sensor that converts the optical signal into an electrical signal. It may also include a processor that determines the particle swarm concentration based on the electrical signal and outputs a particle swarm concentration detection signal. For example, a higher electrical signal intensity indicates a higher particle swarm concentration, while a lower electrical signal intensity indicates a lower particle swarm concentration. This specific correspondence can be configured based on actual conditions. Because the particle swarm pulse signal is a low-frequency signal, a bandpass photoelectric conversion circuit is required. The particle swarm concentration detection signal can be output to a server terminal, such as a computer, allowing users to query the individual particle concentrations through the server terminal.

[0079] Reference Figures 1 to 4 In one embodiment, the second detection channel 40 includes:

[0080] A third convex lens 41 is used to converge the scattered light passing through a single particle and then output it;

[0081] The third aperture 42 is arranged opposite to the third convex lens 41 , and is used for filtering the scattered light emitted by the third convex lens 41 and outputting the filtered light.

[0082] In this embodiment, the third convex lens 41 can first converge the scattered light passing through a single particle and then output it to the third aperture 42 to prevent the light beam from diverging too much and causing inaccurate measurement. The third aperture 42 can be set to correspond to the image point of the third convex lens 41. The third aperture 42 can filter out stray light from the cavity wall and improve the signal-to-noise ratio, so as to facilitate the detection module to detect the Gaussian beam and obtain the concentration of the single particle.

[0083] Reference Figures 1 to 4In one embodiment, the second detection channel further includes:

[0084] A bandpass photoelectric pulse detection module is connected to the third aperture 42 and is used to detect the single particle concentration in the ventilation duct based on the scattered light output by the third aperture 42 and output a single particle concentration detection signal.

[0085] In this embodiment, the bandpass type photoelectric pulse detection module can receive the scattered light output by the third aperture 42, and convert the optical signal into an electrical signal, and then output a single particle concentration detection signal based on the electrical signal. For example, the electrical signal can be a voltage signal or a current signal. The higher the voltage value represented by the voltage signal output by the bandpass type photoelectric pulse detection module, the higher the single particle concentration, and the lower the voltage value represented by the voltage signal, the lower the single particle concentration. The specific corresponding relationship can be set according to actual conditions.

[0086] Reference Figures 1 to 4 In one embodiment, the bandpass photoelectric pulse detection module includes:

[0087] A second light-guiding optical fiber 43 , one end of which is arranged corresponding to the third aperture 42 ;

[0088] A bandpass photoelectric conversion circuit, wherein the input end of the bandpass photoelectric conversion circuit is connected to the other end of the second light-guiding optical fiber 43, and the bandpass photoelectric conversion circuit is used to receive the scattered light output by the third aperture 42 through the second light-guiding optical fiber 43, and detect the single particle concentration in the ventilation duct based on the scattered light output by the third aperture 42, and output a single particle concentration detection signal.

[0089] In this embodiment, one end of the second light-guiding optical fiber 43 receives scattered light from the third aperture 42 and outputs it through the other end to a bandpass photoelectric conversion circuit. The bandpass photoelectric conversion circuit may include a photoelectric sensor that converts the optical signal into an electrical signal. It may also include a processor that determines the single particle concentration based on the electrical signal and outputs a single particle concentration detection signal. For example, a higher electrical signal intensity indicates a higher single particle concentration, while a lower electrical signal intensity indicates a lower single particle concentration. The specific correspondence can be set based on actual conditions. Because the pulse signal of a single particle is an intermediate frequency signal, a bandpass photoelectric conversion circuit is required. The single particle concentration detection signal can be output to a server terminal, such as a computer, through which a user can query the single particle concentration.

[0090] The present invention also provides a flue gas particulate matter detection system, comprising the flue gas particulate matter detection device described above. The specific structure of the flue gas particulate matter detection device is similar to the above-described embodiments. Since the present flue gas particulate matter detection system utilizes all the technical solutions of all the above-described embodiments, it at least possesses all the beneficial effects brought about by the technical solutions of the above-described embodiments, and therefore will not be further elaborated here.

[0091] In one embodiment, the smoke particulate matter detection system further includes:

[0092] An air pump, the outlet of which is connected to the smoke inlet of the smoke particulate matter detection device, and the air pump is used to draw smoke from the smoke inlet into the measuring chamber body 10 of the smoke particulate matter detection device.

[0093] In this embodiment, the vacuum pump refers to an instrument that has one vacuum nozzle and one exhaust nozzle, one inlet and one outlet, and can continuously form a vacuum or negative pressure at the inlet; the working medium is mainly gas. The vacuum pump can draw the smoke from the smoke inlet into the measuring chamber body 10 in the smoke particulate matter detection device, so that the smoke passes through the first detection channel 30 and the second detection channel 40, thereby detecting the particulate matter concentration in the smoke.

[0094] The above descriptions are merely optional embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's description and drawings under the technical concept of the present invention, or any direct / indirect application in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A smoke particulate matter detection device, characterized in that: The smoke particulate matter detection device comprises: a measuring chamber body, the measuring chamber body having a smoke inlet and a smoke outlet, the smoke inlet and the smoke outlet being connected to form a ventilation duct; A laser incident module, the laser incident module is arranged on the measurement cavity body, and the laser incident module is used to emit a Gaussian beam; a first detection channel, the first detection channel being disposed on the measurement cavity body and in communication with the ventilation duct, the first detection channel being disposed directly opposite the laser incident module, the first detection channel being configured to detect a concentration of swarm particles in the ventilation duct based on light scattered by the Gaussian beam from the swarm particles in the ventilation duct, and outputting a swarm particle concentration detection signal; a second detection channel, the second detection channel being disposed on the measurement cavity body and in communication with the ventilation duct, the second detection channel being disposed at an angle to the laser incident module, and being configured to detect a single particle concentration in the ventilation duct based on light scattered by the Gaussian beam from the single particle in the ventilation duct, and output a single particle concentration detection signal; The first detection channel includes a light absorption plate, a second convex lens, a second aperture, and a low-pass photoelectric detection module. The light absorption plate is used to absorb the Gaussian beam directly emitted by the laser incident module. The second convex lens is used to converge the scattered light passing through the group of particles and then output it. The second aperture is arranged directly opposite the second convex lens. The second aperture is used to filter the scattered light emitted by the second convex lens and then output it. The low-pass photoelectric detection module is connected to the second aperture and is used to detect the concentration of the group of particles in the ventilation duct based on the scattered light output by the second aperture and output a group of particles concentration detection signal. The second detection channel includes a third convex lens, a third aperture and a bandpass photoelectric pulse detection module. The third convex lens is used to converge the scattered light passing through the single particle and then output it. The third aperture is arranged opposite the third convex lens. The third aperture is used to filter the scattered light emitted by the third convex lens and then output it. The bandpass photoelectric pulse detection module is connected to the third aperture and is used to detect the concentration of single particles in the ventilation duct based on the scattered light output by the third aperture, and output a single particle concentration detection signal.

2. The smoke particulate matter detection device according to claim 1, characterized in that: The laser incident module includes: a laser diode configured to emit a Gaussian beam; a first aperture, the first aperture being arranged opposite to the laser diode so that the Gaussian beam becomes a circular divergent shape after passing through the first aperture; A first convex lens is provided opposite to the first aperture, and the Gaussian beam is converged by the first convex lens and then output.

3. The smoke particulate matter detection device according to claim 1, characterized in that: The low-pass photoelectric detection module includes: a first light-guiding optical fiber, one end of which is arranged corresponding to the second aperture; A low-pass photoelectric conversion circuit, wherein the input end of the low-pass photoelectric conversion circuit is connected to the other end of the first light-guiding optical fiber, the low-pass photoelectric conversion circuit is used to receive the scattered light output by the second aperture through the first light-guiding optical fiber, detect the group particle concentration in the ventilation duct based on the scattered light output by the second aperture, and output a group particle concentration detection signal.

4. The smoke particulate matter detection device according to claim 1, characterized in that: The bandpass photoelectric pulse detection module includes: a second light-guiding optical fiber, one end of which is arranged corresponding to the third aperture; a bandpass photoelectric conversion circuit, wherein the input end of the bandpass photoelectric conversion circuit is connected to the other end of the second light-guiding optical fiber, the bandpass photoelectric conversion circuit is used to receive the scattered light output by the third aperture through the second light-guiding optical fiber, detect the single particle concentration in the ventilation duct based on the scattered light output by the third aperture, and output a single particle concentration detection signal.

5. A smoke particulate matter detection system, characterized in that: The smoke particulate matter detection system includes the smoke particulate matter detection device according to any one of claims 1 to 4.

6. The smoke particulate matter detection system according to claim 5, characterized in that: The flue gas particulate matter detection system further includes: An air pump, the outlet of which is connected to the smoke inlet of the smoke particle detection device, and the air pump is used to draw smoke from the smoke inlet into the measuring cavity body of the smoke particle detection device.

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