Ammonia gas detection device

Abstract

The utility model relates to the field of ammonia gas detection of diesel vehicles in use, in particular to an ammonia gas detection device. Comprising a light cutting sheet; the light cutting sheet is arranged at the output end of the driving device; the light cutting sheet is positioned between a first detection light source of the ammonia gas detection device and a light inlet of a first detection gas chamber; the driving device is used for driving the light cutting sheet to periodically rotate and periodically shielding light rays entering the first detection gas chamber from the first detection light source so as to generate alternating input signals, and a plurality of reflection units are arranged on the inner side of the first detection gas chamber and used for reflecting the light rays entering the first detection gas chamber for multiple times. According to the utility model, the frequency of the generated alternating light signal can be adjusted by the shielding frequency of the light cutting sheet. Therefore, the alternating light signal can be distinguished from the light signal of the direct current drifting by enabling the alternating light signal to have relatively high frequency, so that the signal generated by the direct current drifting can be inhibited and eliminated subsequently, the stability of the ammonia gas detection device is improved, and the detection precision is improved.

Description

Technical Field

[0001] This utility model relates to the field of ammonia detection in in-use diesel vehicles, and in particular to an ammonia detection device. Background Technology

[0002] Ammonia detection refers to the process of measuring and monitoring the concentration of ammonia (NH3) using specific sensors or detection technologies. Ammonia is a common toxic gas, and high concentrations of NH3 can harm human health and the environment. Ammonia detection plays an important role in industrial safety, environmental monitoring, and agricultural production. Accurate measurement of ammonia concentration can be achieved through technologies such as electrochemical sensors, optical sensors, and semiconductor sensors.

[0003] In existing ammonia detection equipment, the baseline of the output signal of the electronic or measurement system will slowly change due to the influence of time or environmental conditions (such as temperature, power fluctuations, etc.), which is called DC drift. This will affect the accuracy of ammonia detection. In addition, in existing ammonia detection equipment using infrared optics, the optical channel required for ammonia detection is relatively long, which makes the overall size of the ammonia detection equipment large, difficult to carry and move, and requires a large installation space. Summary of the Invention

[0004] In view of this, the present invention provides an ammonia detection device, which at least partially solves the problems existing in the prior art.

[0005] According to one aspect of the present invention, an ammonia detection device is provided, comprising: a driving device, a first detection chamber, and a light cutter;

[0006] The beam cutter is located at the output end of the drive device;

[0007] The cutter is located between the first detection light source and the light inlet of the first detection chamber in the ammonia detection device; the driving device is used to drive the cutter to rotate periodically to periodically block the light from the first detection light source entering the first detection chamber, thereby generating an alternating input signal; the first detection chamber is used to detect the ammonia concentration.

[0008] Multiple reflective units are provided inside the first detection chamber. The reflective units are used to reflect the light incident into the first detection chamber multiple times, and finally emit it out of the light outlet of the first detection chamber.

[0009] Furthermore, it also includes: a second detection chamber, a gas supply pipe, a second detection light source, and a water vapor concentration sensor;

[0010] The second detection light source is located on one side of the light inlet of the second detection gas chamber. Both the second and first detection light sources are continuous spectrum light sources. The second and first detection gas chambers are arranged side by side. The second detection gas chamber is used to detect CH4 and CO. 2、 CO concentration;

[0011] The gas supply pipe includes a main gas pipe and two branch gas pipes. Both branch gas pipes are connected to the main gas pipe and are respectively connected to the air inlet of the first detection chamber and the air inlet of the second detection chamber. A water vapor concentration sensor is installed on the gas supply pipe.

[0012] Furthermore, it also includes: two detectors;

[0013] One of the detectors is located on the light outlet side of the first detection chamber and is used to detect the light energy when light is emitted from the first detection chamber;

[0014] Another detector is located on the light outlet side of the second detection chamber to detect the light energy emitted from the second detection chamber.

[0015] Furthermore, it also includes: a detector and two optical path adjustment components, the two optical path adjustment components being respectively disposed on the light outlet side of the first detection gas chamber and the second detection gas chamber;

[0016] Each optical path adjustment component includes at least one reflector, which is used to transmit the detection light emitted from the light outlet of the corresponding detection chamber to the detector.

[0017] Furthermore, it also includes a heating device, which is installed outside the first detection chamber.

[0018] Furthermore, the detector is a dual-channel detector or a multi-channel detector.

[0019] Furthermore, it also includes: signal processors;

[0020] The signal processor is connected to the detector and is used to amplify and filter the detector's output signal.

[0021] Furthermore, the light cutter includes a fixed end and light-shielding fan blades;

[0022] The fixed end is connected to the output end of the drive device; the light-shielding fan blades are fixedly connected to the outer peripheral sidewall of the fixed end.

[0023] The drive unit includes a motor.

[0024] Furthermore, both the first and second detection light sources are controlled using constant voltage or constant current control modes.

[0025] Furthermore, it also includes a sampling module, a pre-processing module, a gas path control module, a main control module, a display module, and a communication module;

[0026] The sampling module is connected to the pre-processing module, the pre-processing module is connected to the gas path control module, and the gas path control module is connected to the first detection gas chamber.

[0027] The sampling module, preprocessing module, gas path control module, main control module, display module, communication module, and drive device are all connected to the main control module.

[0028] The technical solution of this utility model has at least the following beneficial effects:

[0029] In this invention, a periodically rotating light cutter is provided between the first detection light source and the light inlet of the first detection gas chamber in the ammonia gas detection device to periodically block and open the light that is about to enter the first detection gas chamber. This modulates the incident light and transforms the incident continuous light signal into an alternating light signal.

[0030] Meanwhile, since DC drift typically manifests as a low-frequency or DC component, the frequency of the alternating light signal generated in this invention can be adjusted by the blocking frequency of the cutter. Therefore, by giving the alternating light signal a higher frequency, it can be distinguished from the DC drift light signal, thus facilitating subsequent suppression and elimination of the DC drift signal, improving the stability and detection accuracy of the ammonia detection device.

[0031] In addition, by setting multiple reflective units (such as reflectors) in the first detection chamber for detecting ammonia concentration, the test light is refracted multiple times in the first detection chamber, thereby increasing the length of the ammonia detection light channel in a limited space. This not only improves the detection accuracy but also significantly reduces the size of the ammonia detection device. Attached Figure Description

[0032] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of an ammonia detection device according to one embodiment of this application;

[0034] Figure 2 This is a schematic diagram of the gas path and circuit connection between each module and the ammonia detection device in another embodiment of this application;

[0035] Figure 3 This is a schematic diagram of the external structure of the ammonia detection device in another embodiment of this application;

[0036] Figure 4 This is a schematic diagram of the ammonia detection device corresponding to two detectors in another embodiment of this application;

[0037] Figure 5 This is a schematic diagram of the structure of an ammonia detection device corresponding to a detector and two optical path adjustment components in another embodiment of this application.

[0038] Figure Labels

[0039] 1. Reflector; 2. First detection light source; 3. Light cutter; 4. Light inlet; 5. First detection chamber; 6. Detector; 7. Signal processor; 8. Light outlet; 9. Air outlet; 10. Air inlet; 11. Motor; 12. Sampling module; 13. Preprocessing module; 14. Gas path control module; 15. Main control module; 16. Display module; 17. Communication module; 18. Second detection light source; 19. Second detection chamber; 20. Water vapor concentration sensor; 21. Gas supply pipe; 22. Reflector. Detailed Implementation

[0040] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0041] It should be noted that, unless otherwise specified, the following embodiments and features can be combined with each other; and, based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0042] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this disclosure, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0043] As one embodiment of this utility model, such as Figure 1 As shown, an ammonia detection device is provided, including: a driving device and a cutter 3.

[0044] The light cutter 3 is disposed at the output end of the driving device. The light cutter 3 is located between the first detection light source 2 and the light inlet 4 of the first detection chamber 5 of the ammonia detection device. The driving device is used to drive the light cutter 3 to rotate periodically, periodically blocking the light from the first detection light source 2 entering the first detection chamber 5, so as to generate an alternating input signal.

[0045] In this embodiment, the driving device can be a motor 11. The light cutter 3 rotates under the drive of the motor 11, thereby periodically blocking and opening the detection light rays about to enter the light inlet 4, so that the incident light rays change from a continuous light signal to an alternating light signal. Alternatively, the driving device in this embodiment can also be other devices in the prior art capable of rotational drive, or devices capable of reciprocating oscillation or movement.

[0046] Specifically, a possible structural form of the light cutter 3 is also provided: the light cutter 3 includes a fixed end and a light-shielding fan blade.

[0047] The fixed end is connected to the output end of the drive unit. The light-shielding fan blades are fixedly connected to the outer peripheral side wall of the fixed end. The light-shielding fan blades can be made of opaque material, thereby achieving complete blocking of incident light. In addition, the number of light-shielding fan blades and the spacing between them can be adaptively set according to the requirements such as the light-shielding frequency required in actual use.

[0048] In addition, to ensure that the output light source emits stable detection light, the first detection light source 2 can be controlled using a constant voltage or constant current control mode. The ammonia detection device also includes: a reflector cup 1.

[0049] A reflector cup 1 is positioned on the side of the first detection light source 2 away from the light inlet 4, and is used to reflect a portion of the light emitted by the first detection light source 2 that is on the opposite side of the light inlet 4 back to the light inlet 4. This reflects the light emitted by the first detection light source 2 back to the light inlet 4, improving the energy utilization rate of the light source. A reflector cup 1 structure can also be correspondingly provided at the second detection light source 18.

[0050] Furthermore, multiple reflecting units are arranged inside the first detection chamber 5. These reflecting units are used to reflect the light incident into the first detection chamber 5 multiple times, and finally emit it from the light outlet 8 of the first detection chamber 5. In this embodiment, the reflecting units can be mirrors 22 or other existing reflective devices. By setting the reflecting units, the input detection light can be reflected multiple times within the limited space of the first detection chamber 5 before being emitted. This increases the optical path length of the detection light within the first detection chamber 5 and also helps the ammonia gas to fully absorb the detection light, thereby improving the detection accuracy of ammonia gas.

[0051] In addition, the first detection chamber 5 is also provided with an air inlet 10 and an air outlet 9, so as to input the corresponding gas into the first detection chamber 5.

[0052] The ammonia detection device also includes: detector 6.

[0053] Detector 6 is positioned on one side of the light outlet 8 of the first detection chamber 5 to detect the light energy emitted from the first detection chamber 5. In this embodiment, the light energy can be light intensity.

[0054] In this embodiment, detector 6 can sense light energy of a specific spectrum, and ammonia absorbs light energy under this specific spectrum. Based on this, the ammonia detection device in this embodiment uses the principle of infrared non-dispersive light to detect the concentration of ammonia. Due to the absorption characteristics of ammonia to infrared light of a specific wavelength, the concentration of ammonia is estimated by measuring the intensity attenuation of the detection light (i.e., infrared light of a specific wavelength) after passing through the first detection chamber 5.

[0055] Furthermore, detector 6 is a dual-channel detector 6 or a multi-channel detector 6.

[0056] Preferably, the detector 6 in this embodiment is dual-channel or multi-channel. The other channels can be used to sense light signals of other spectra as a reference or to compensate for ammonia signals, so as to improve detection accuracy.

[0057] In addition, to prevent water vapor condensation, improve sensor response speed, reduce interference, and enhance detection accuracy, it is necessary to heat relevant components in the ammonia detection device (such as the first detection chamber 5) to a temperature environment above 120°C. This can be achieved by placing a heating device (such as a heating wire) around the outside of the first detection chamber 5.

[0058] The ammonia detection device also includes: a signal processor 7.

[0059] Signal processor 7 is communicatively connected to detector 6 and is used to amplify and filter the output signal of detector 6. In this application scenario, the signal output by detector 6 is usually very weak and needs to be amplified to improve the signal-to-noise ratio. Simultaneously, noise and low-frequency drift in the signal need to be filtered out to retain useful signal components. Therefore, in this embodiment, signal processor 7 is used to amplify and filter the output signal of detector 6 for subsequent AD conversion.

[0060] The ammonia detection device in this example, by setting a light cutter and a reflective unit in the first detection chamber 5, not only improves the detection accuracy of ammonia but also significantly reduces the size of the device. The ammonia detection device prepared in this embodiment is as follows: Figure 3As shown, specifically, the device's size can be reduced to the following dimensions: 30cm long, 24cm high, and 26cm wide. This makes it more convenient to move and carry.

[0061] Therefore, the ammonia detection device in this embodiment is more suitable for detecting ammonia slip in the exhaust of in-use diesel vehicles. Specifically, the SCR (Selective Catalytic Reduction) device in diesel vehicle exhaust treatment systems generates ammonia slip during operation. Ammonia emissions from new vehicles can be detected in a laboratory using large infrared detectors, but large optical instruments are not suitable for detecting ammonia emissions from in-use diesel vehicles because smaller instruments lack precision. Therefore, they are not suitable for detecting ammonia in the exhaust of in-use diesel vehicles. The ammonia detection device in this embodiment is more compact and portable, making it more suitable for detecting ammonia slip in the exhaust of in-use diesel vehicles, thus solving the problem of ammonia detection in the exhaust of in-use diesel vehicles.

[0062] Specifically, the working principle of the ammonia detection device in this utility model is as follows:

[0063] 1. Control the first detection light source 2 to emit stable detection light; the detection light emitted by the first detection light source 2 is infrared light with a continuous spectrum. Since diesel vehicle exhaust has a certain degree of corrosiveness, and the infrared optical method is superior to the electrochemical sensor method in terms of accuracy, stability, and durability, the infrared optical method is used for measurement. Meanwhile, electrochemical sensors have poor accuracy and age quickly. Therefore, electrochemical sensors are not used for quantitative detection.

[0064] 2. Control the motor 11 to rotate periodically, driving the light cutter 3 to rotate, so as to modulate the detection light that is about to enter the light inlet 4;

[0065] 3. High-purity N2 is introduced into the first detection chamber 5, and the values ​​amplified by the signal processor 7 of each channel of the detector 6 are recorded as zero point S0; The detector 6 in this utility model is a detector 6 with a filter in the prior art, which can control the detection light of different wavelengths to enter the detector through the filter and generate the corresponding detection signal.

[0066] 4. Introduce the NH3 to be measured and record the signal value S of the NH3 channel of detector 6;

[0067] 5. Calculate the gas concentration of NH3 based on the signals of S and S0.

[0068] As another possible embodiment of this utility model, such as Figure 2 As shown, it also includes a sampling module 12, a pre-processing module 13, a gas path control module 14, a main control module 15, a display module 16, and a communication module 17.

[0069] The sampling module 12 is connected to the pre-processing module 13 via a gas path, the pre-processing module 13 is connected to the gas path control module 14 via a gas path, and the gas path control module 14 is connected to the first detection gas chamber 5 via a gas path.

[0070] Specifically, the sampling module 12 uses an air pump to extract sample gas and transmits it through a pipeline to the pre-processing module 13 for pretreatment. The sampling module 12 generally needs to be heated to a temperature above 120°C. The sample gas is typically the gas containing NH3 to be tested, including automotive exhaust gases and industrial exhaust gases. The pre-processing module 13 is a high-efficiency filter, mainly used to remove particulate matter from the sample gas. The pre-processing module 13 and the gas path control module 14 are connected via a gas path so that the sample gas after particulate matter removal is input into the first detection gas chamber 5 through the air inlet 10. In addition, the gas path control module 14 can also be connected to the supply devices for zero gas and standard gas. Thus, the gas path control module 14 can be used to switch different gas paths to introduce the corresponding gas (including selecting zero gas, standard gas, sample gas, etc.) into the first detection gas chamber 5. The gas path control module 14 can generally be implemented using a solenoid valve.

[0071] The sampling module 12, the preprocessing module 13, the gas path control module 14, the main control module 15, the display module 16, the communication module 17, and the drive device are all connected to the main control module 15.

[0072] The main control module 15 is used to control the above-mentioned components so that each component can perform its corresponding function.

[0073] Display module 16: Displays the human-computer interaction interface, showing the measurement results and operation prompts.

[0074] Communication module 17: Uploads the measurement results to the user terminal via wireless or wired means.

[0075] Measurement platform (i.e., the ammonia detection device in this invention): A device for measuring ammonia concentration, which generally requires heating to a temperature above 120°C. In this embodiment, the main control module 15 can communicate with the components in the ammonia detection device that require control, in order to control the corresponding components.

[0076] Main control module 15: Controls the operation of all the above components. Additionally, these modules can be added or removed as needed.

[0077] As another possible embodiment of this utility model, such as Figure 4 and Figure 5 As shown, the ammonia detection device also includes: a second detection chamber 19, a gas supply pipe 21, a second detection light source 18, and a water vapor concentration sensor 20.

[0078] The second detection light source 18 is disposed on one side of the light inlet 4 of the second detection chamber 19. Both the second detection light source 18 and the first detection light source 2 are continuous spectrum light sources, emitting infrared detection light of continuous wavelength. The second detection chamber 19 is disposed side by side with the first detection chamber 5, and the second detection chamber 19 is used to detect the concentrations of CH, CO2 and CO.

[0079] In this utility model, the specific arrangement of the second detection light source 18 and the first detection light source 2 can be any of the following:

[0080] First, there are two independent light sources, each positioned on one side of the corresponding detection gas chamber's light inlet 4. Second, there is one light source and a beam splitter. The beam emitted by the light source is split into two beams by the beam splitter, which then enter the first detection gas chamber 5 and the second detection gas chamber 19, respectively. Specifically, the beam splitter can be an existing beam splitter, or it can be constructed by using multiple reflectors 22 in combination. For example, by swapping the light inlet and outlet positions of the light path adjustment components described below, a beam splitter usable in this embodiment can be formed.

[0081] Since diesel vehicle exhaust contains not only ammonia but also hydrocarbon gases (CH), CO2, CO, and water vapor, it is necessary to measure the concentration of these gases to improve detection accuracy. This allows for correction of the ammonia concentration measured in the first detection chamber 5, further enhancing the accuracy of ammonia detection. Therefore, this embodiment provides a second detection chamber 19 to detect the concentrations of CH, CO2, and CO. Furthermore, since the required optical channel length for detecting CH, CO2, and CO concentrations is relatively short, the second detection chamber 19 in this embodiment does not require a reflection unit, thus improving the simplicity of the device structure. Additionally, the second detection chamber 19 can be made to have approximately the same length as the first detection chamber 5, allowing for parallel arrangement to avoid an excessively large ammonia detection device.

[0082] The gas supply pipe 21 includes a main gas pipe and two branch gas pipes. Both branch gas pipes are connected to the main gas pipe and are respectively connected to the air inlet of the first detection chamber 5 and the air inlet of the second detection chamber 19. A water vapor concentration sensor 20 is installed on the gas supply pipe 21.

[0083] In this embodiment, the water vapor concentration is detected by setting a water vapor concentration sensor 20 on the gas supply pipe 21 to obtain the water vapor concentration.

[0084] In this embodiment, the detection light emitted after passing through the first detection chamber 5 and the detection light emitted after passing through the second detection chamber 19 need to be detected by the detector 6 to form a signal about the absorption intensity of the detection light by different gases. Then, the signal processor 7 amplifies and filters the signal to generate the corresponding concentration detection value.

[0085] Regarding the configuration of detector 6 in this embodiment, the following two forms are provided:

[0086] Firstly

[0087] like Figure 4 As shown, two detectors 6 are set up.

[0088] One of the detectors 6 is located on the light outlet side of the first detection chamber 5 and is used to detect the light energy when light is emitted from the first detection chamber 5.

[0089] Another detector 6 is located on the light outlet side of the second detection chamber 19 to detect the light energy emitted from the second detection chamber 19.

[0090] Therefore, the detection light emitted from the two detection chambers is detected separately by two independent detectors 6, and then the two detectors 6 send the signals to the signal processor 7.

[0091] Secondly

[0092] like Figure 5 As shown, a detector 6 and two optical path adjustment components are set up.

[0093] Two optical path adjustment components are respectively located on the light outlet side of the first detection chamber 5 and the second detection chamber 19.

[0094] Each optical path adjustment component includes at least one reflector 22, which is used to transmit the detection light emitted from the corresponding detection gas chamber outlet to the detector 6.

[0095] like Figure 4 As shown, the detection light emitted from the detection chamber can be transmitted to the detector 6 through two reflectors 22, thereby reducing the number of detectors 6 required. Furthermore, to avoid interference between the light rays from the two detection chambers, the emission times of the detection light rays from the two chambers can be staggered. In this embodiment, factors that interfere with the ammonia detection value in diesel vehicle exhaust are detected, and the detected values ​​are used to correct the ammonia detection value, further improving the accuracy of ammonia detection.

[0096] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. An ammonia detection device, characterized by, The application relates to an ammonia gas detection device. The device comprises a driving device, a first detection gas chamber and a light cutting piece. The light cutting piece is arranged at the output end of the driving device. The light cutting piece is located between a first detection light source and a light inlet of the first detection gas chamber of the ammonia gas detection device. The driving device is used for driving the light cutting piece to periodically rotate, so that the first detection light source periodically blocks the light entering the first detection gas chamber, and an alternating input signal is generated.

2. The ammonia detection device of claim 1, wherein A plurality of reflection units are arranged on the inner side of the first detection gas chamber. The reflection units are used for reflecting the light entering the first detection gas chamber for multiple times, and finally the light is emitted from a light outlet of the first detection gas chamber. The device further comprises a second detection gas chamber, a gas supply pipe, a second detection light source and a water vapor concentration sensor. The second detection light source is arranged on one side of a light inlet of the second detection gas chamber.

3. The ammonia detection device of claim 2, wherein The second detection light source and the first detection light source are both continuous spectrum light sources. The second detection gas chamber is arranged in parallel with the first detection gas chamber. The second detection gas chamber is used for detecting CH and CO2 concentrations. The gas supply pipe comprises a main gas pipe and two branch gas pipes.

4. The ammonia detection device of claim 2, wherein The two branch gas pipes are in communication with the main gas pipe. The two branch gas pipes are respectively connected with the gas inlets of the first detection gas chamber and the second detection gas chamber. The water vapor concentration sensor is arranged on the gas supply pipe.

5. The ammonia detection device of claim 1, wherein The device further comprises two detectors.

6. The ammonia detection device of claim 3, wherein One of the detectors is arranged on one side of a light outlet of the first detection gas chamber and is used for detecting the light energy of the light emitted from the first detection gas chamber.

7. An ammonia detection device according to claim 4 or 3, characterised in that The other detector is arranged on one side of a light outlet of the second detection gas chamber and is used for detecting the light energy of the light emitted from the second detection gas chamber. The device further comprises one detector and two light path adjusting assemblies. The two light path adjusting assemblies are respectively arranged on one side of a light outlet of the first detection gas chamber and the second detection gas chamber.

8. The ammonia detection device of claim 1, wherein, Each light path adjusting assembly comprises at least one reflector. The reflector is used for conveying the detection light emitted from the light outlet of the corresponding detection gas chamber to the detector. The device further comprises a heating device which is sleeved on the outer side of the first detection gas chamber.

9. The ammonia detection device of claim 2, wherein, The detector is a double-channel detector or a multi-channel detector.

10. The ammonia detection device of claim 1, wherein, The device further comprises a signal processor. The signal processor is in communication connection with the detector and is used for amplifying and filtering the output signal of the detector. The light cutting piece comprises a fixed end and a light shielding fan blade. The fixed end is connected with the output end of the driving device. The light shielding fan blade is fixedly connected on the outer peripheral side wall of the fixed end. The driving device comprises a motor. The first detection light source and the second detection light source are controlled by using a constant voltage or constant current control mode. The device further comprises a sampling module, a pre-processing module, a gas path control module, a main control module, a display module and a communication module. The sampling module is connected with the pre-processing module. The pre-processing module is connected with the gas path control module. The gas path control module is connected with the first detection gas chamber. The sampling module, the pre-processing module, the gas path control module, the main control module, the display module, the communication module and the driving device are in communication connection with the main control module.

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