Multi-component laser gas analyzer based on front-end pretreatment

Abstract

The invention discloses a multi-component laser gas analyzer based on front-end pretreatment, and relates to the technical field of gas detection, the multi-component laser gas analyzer specifically comprises a portable box, a control panel is arranged in the portable box, and a laser gas analysis mechanism is mounted in the portable box and located at the bottom of the control panel; the problem of spectral signal distortion caused by a high-dust and high-humidity environment in industrial gas detection is solved through a front-end pretreatment self-adaptive technology, system downtime caused by single-path blockage is avoided through a double-pipeline redundancy design aiming at the high-dust and high-humidity environment, rapid dehumidification and cooling of a compression and condensation assembly are combined, and the detection efficiency is improved. According to the multi-component laser gas analyzer system, a laser gas analysis mechanism can stably obtain high-precision spectral signals under complex working conditions, meanwhile, multi-stage intelligent early warning and filter element health management are adopted in the system, the maintenance cost is reduced, the service life of equipment is prolonged, the integrated design of the portable box supports on-site rapid overhaul, and the detection efficiency of the whole multi-component laser gas analyzer is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of gas detection, in particular to a multi-component laser gas analyzer based on front-end preprocessing. Background Art

[0002] Laser absorption spectroscopy (TDLAS) technology uses the narrow linewidth and wavelength tunable characteristics of tunable semiconductor lasers to detect the characteristic gas "fingerprint" absorption lines. It has the advantages of high sensitivity, high resolution, fast response, and non-contact monitoring. Combining TDLAS technology with long optical path technology and weak signal detection technology can achieve high time resolution and high sensitivity trace gas detection.

[0003] Extractive analyzers extract gases from industrial processes through sampling probes. Exhaust gases are subject to high levels of dust, significant water vapor interference, and high measured gas temperatures. Therefore, extractive measurement methods require pretreatment of the sampled gas after pumping, such as filtration, condensation, and drying. This is evident in the invention patent publication number CN119901707A, titled "An In-Situ Laser Gas Analyzer."

[0004] The filter element is self-cleaned by setting up a filter component to purify the gas and back-flushing with external nitrogen and on-site gas. However, the overall back-flushing requires external nitrogen or consumes the gas being measured, which affects continuous detection. At the same time, the overall anti-interference ability of the equipment is weak. It only controls the temperature of the box and does not solve the optical interference of comprehensive factors such as humidity on the laser sensor. It also lacks adaptive pre-processing adjustment for measurement environments with high dust and high humidity and complex working conditions, and cannot continuously and stably obtain spectral signals with high precision in complex environments. Summary of the Invention

[0005] The object of the present invention is to provide a multi-component laser gas analyzer based on front-end preprocessing, so as to solve the problems mentioned in the background technology.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a multi-component laser gas analyzer based on front-end preprocessing, comprising a portable case, a control panel disposed within the portable case, a laser gas analysis mechanism mounted within the portable case and at the bottom of the control panel, and an adaptive preprocessing mechanism mounted on the side of the laser gas analysis mechanism;

[0007] The adaptive pre-processing mechanism includes a shell, a sealing rotary disk, a first through hole, a second through hole and a switching control box. The shell is fixedly installed in the portable box, and a transmission assembly is installed on the side of the shell.

[0008] A sealing rotary disc is movably connected in the housing, an output end of a motor installed in the transmission assembly is fixed to the sealing rotary disc, and a through hole 1 and a through hole 2 are opened on one side of the housing, and the through hole 1 and the through hole 2 are connected to the housing;

[0009] A switching control box is fixed to one side of the shell by bolts, and a drain outlet is provided at the bottom of the shell. The switching control box includes a front-end data acquisition module, a pollution index comparison module and a dual-line purification switching module. A sheath is fixed on one side of the through hole one and the through hole two, and a filtering mechanism is installed on the top of the sheath.

[0010] Furthermore, the front-end data acquisition module is used to obtain the dust concentration, humidity and temperature in the exhaust gas in real time, and send the collected data to the pollution index comparison module. The pollution index comparison module processes the collected data parameters according to the normalization formula to obtain a comprehensive pollution index, and compares it with the stored threshold to generate a steering control signal and send it to the dual-pipeline purification switching module. The dual-pipeline purification switching module is used for motor steering control on the transmission component.

[0011] Furthermore, the laser gas analysis mechanism includes a detection pipe, a laser emitting unit, a receiving detection unit and a signal processing unit. The detection pipe is fixed to the inner wall of the bottom of the portable box. The laser emitting unit is provided on one side of the detection pipe, and the receiving detection unit is provided on the other side. The signal processing unit is installed on the receiving detection unit, and the signal processing unit is electrically connected to the control panel.

[0012] Furthermore, an air outlet pipe and an air inlet pipe are provided at the rear of the portable box, and one end of the air inlet pipe is connected to the top of the shell, and one end of the air outlet pipe is connected to the detection pipe in the laser gas analysis mechanism.

[0013] Furthermore, a compression condensation component is installed on the side of the sheath, a second heat dissipation port is opened on the portable box and located on the side of the compression condensation component, a first heat dissipation port is opened symmetrically on the rear side of the portable box, and a four-core aviation plug is provided on the portable box and located on the side of the heat dissipation port.

[0014] Furthermore, the filtering mechanism includes a main filter cartridge, an auxiliary filter cartridge, a filter element and a back-blowing pipe. The main filter cartridge and the auxiliary filter cartridge are respectively installed on the top of the sheath. Filter elements are placed in the main filter cartridge and the auxiliary filter cartridge. A back-blowing pipe is provided on the main filter cartridge and the auxiliary filter cartridge inside the filter element. A dust exhaust pipe is fixed to the side walls of the main filter cartridge and the auxiliary filter cartridge.

[0015] Furthermore, the filtering mechanism further comprises an alarm box, the top of the main filter cartridge and the auxiliary filter cartridge are equipped with an alarm box, and a pressure difference monitoring module and an alarm module are installed in the alarm box;

[0016] Among them, the pressure difference monitoring module is used to obtain the pressure difference data between the main filter cartridge and the auxiliary filter cartridge based on the inside and outside of the filter element within unit time, and feed it back to the alarm module. The alarm module is used to compare the pressure difference data with the stored pressure difference threshold, and generate a passive steering signal to send to the dual-line purification switching module, and directly generate an alarm signal to remind the replacement of the filter element.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present invention adopts adaptive dual-line purification and intelligent switching mechanism to significantly improve the measurement stability under complex working conditions. By switching the front-end data acquisition module of the control box, the dust concentration, humidity, temperature, pollution index comparison module and normalization processing are used to generate the comprehensive pollution index CPI in real time. The system can dynamically evaluate the gas pollution load. When the CPI and the pressure difference on both sides of the pipeline filter element exceed the threshold at the same time, the dual-line purification switching module immediately controls the transmission component to drive the sealing disc to rotate, switching the airflow from the current path to the backup path. The two independent gas paths are physically isolated by the sealing disc. When one path is working, the other path automatically triggers the backflush pipe for self-cleaning, and at the same time closes the valve of the path to avoid gas interference, ensuring detection continuity and filter element regeneration efficiency.

[0019] For high-dust and high-humidity environments, the dual-pipeline redundant design avoids system downtime caused by single-line blockage. Combined with the rapid dehumidification and cooling of the compression condensation component, it ensures that the laser gas analysis mechanism can stably obtain high-precision spectral signals under complex working conditions.

[0020] 2. In the present invention, multi-level intelligent early warning and filter element health management are adopted to reduce maintenance costs and extend equipment life. The pressure difference monitoring module in the alarm box collects the pressure difference data of the inside and outside of the filter element in the main or auxiliary filter cartridge in real time. When the pressure difference exceeds the threshold, a passive steering signal is generated, and the front-end flue gas collection is coordinated to complete the dual-pipeline purification switching module to execute the path switching. If the pressure difference of the new path still exceeds the standard after switching, it is determined that the filter element is seriously clogged, and the alarm module is triggered to remind the filter element to be replaced. At the same time, dynamic weight adjustment is made to avoid frequent incorrect switching. At the same time, the pressure difference change trend is monitored to accurately distinguish "temporary pollution" from "hardware failure". The coordination of backwash self-cleaning and pressure difference alarm extends the filter element replacement cycle by more than 40%, and the integrated design of the portable box supports on-site rapid maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the overall structure of the multi-component laser gas analyzer with front-end pretreatment of the present invention;

[0022] Figure 2 Schematic diagram of removing the cover of the multi-component laser gas analyzer with front-end pretreatment of the present invention;

[0023] Figure 3 This is a schematic diagram of the inner structure of the multi-component laser gas analyzer with front-end pretreatment of the present invention;

[0024] Figure 4 This is a schematic diagram of the connection structure between the adaptive pre-treatment mechanism, the sheath, and the filtering mechanism of the present invention;

[0025] Figure 5 This is a schematic diagram of the front view of the connection between the adaptive pre-treatment mechanism, the sheath, and the filtering mechanism of the present invention;

[0026] Figure 6 Schematic diagram of the connection between the upper ventilation channel of the sealing rotary disk and the second through hole of the present invention;

[0027] Figure 7 It is a schematic diagram of the overall structure of the filtering mechanism of the present invention.

[0028] In the figure: 1. Portable box; 2. Control panel; 3. Laser gas analysis mechanism; 301. Detection pipeline; 302. Laser emission unit; 303. Receiving detection unit; 304. Signal processing unit; 4. Exhaust pipe; 5. Inlet pipe; 6. Four-core aviation plug; 7. Heat dissipation port 1; 8. Heat dissipation port 2; 9. Adaptive pretreatment mechanism; 901. Shell; 902. Transmission assembly; 903. Sealing rotary disc; 904. Through hole 1; 905. Through hole 2; 906. Switching control box; 907. Drain port; 10. Compression condensation assembly; 11. Sheath; 12. Filter mechanism; 121. Main filter cartridge; 122. Filter element; 123. Backflush pipe; 124. Alarm box; 125. Dust exhaust pipe; 126. Auxiliary filter cartridge. DETAILED DESCRIPTION

[0029] 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. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] See also Figure 1-7 , the present invention provides a technical solution:

[0031] like Figure 1-2 As shown, the multi-component laser gas analyzer based on front-end preprocessing is mainly used to monitor trace gas concentrations. The sample gas to be tested enters the adaptive preprocessing mechanism 9 through the inlet pipe 5, and after preliminary processing, it enters the laser gas analysis mechanism 3 for detection, and is then discharged from the outlet pipe 4. The laser in the laser gas analysis mechanism 3 works and completes the absorption spectrum data collection of the gas to be tested. The concentration of the gas to be tested is obtained and displayed in real time on the built-in touch screen control panel 2. At the same time, it supports data interface uploading to the remote user control system;

[0032] This equipment designs and develops adaptive high-precision signal preprocessing and acquisition components for industrial gases. For measurement environments with high dust and high humidity, the equipment studies adaptive high-precision signal preprocessing and acquisition components based on feedback control, focusing on signal preprocessing technology based on digital automatic gain control to achieve high-precision and stable acquisition of spectral signals in complex environments.

[0033] To this end, an adaptive pretreatment mechanism 9 is set up in the portable box 1, and two gas pretreatment circulation pipelines are alternately coordinated. At the same time, a backwashing device is set to complete the pretreatment effect correction. Then, the sheath 11 side compression condensation component 10 and the filtering mechanism 12 are used to achieve efficient pre-processing during industrial gas detection. A sealing rotary disk 903 that can switch the flow direction is set in the shell 901 of the entire adaptive pretreatment mechanism 9, as shown in FIG. Figure 6 As shown, industrial gas enters the housing 901 through the air inlet pipe 5, and the transmission assembly 902 on the housing 901 controls the rotation of the sealing disc 903;

[0034] like Figure 6 At this time, the industrial gas passes through the sealing rotary disk 903 and reaches the side of the second through-hole 905. When the entire sealing rotary disk 903 rotates 30 degrees counterclockwise, the air inlet pipe 5 is now connected to the first through-hole 904. The cyclic rotation of the sealing rotary disk 903 realizes the switching of the industrial gas flow between the first through-hole 904 and the second through-hole 905. The switching rate is high, which prevents the gas flow fluctuation from affecting the operation of the analyzer.

[0035] A switching control box 906 is installed on the side of the housing 901. The switching control box 906 includes a front-end data acquisition module, a pollution index comparison module, and a dual-pipeline purification switching module. The front-end data acquisition module is used to obtain the dust concentration, humidity, and temperature in the exhaust gas in real time, and send the collected data to the pollution index comparison module. The pollution index comparison module performs a normalization formula on the collected data parameters to obtain a comprehensive pollution index, and compares it with the stored threshold to generate a steering control signal and send it to the dual-pipeline purification switching module. The dual-pipeline purification switching module is used for steering control of the motor on the transmission component 902;

[0036] For the acquisition of collected data, the front-end data acquisition module is equipped with dust sensors, humidity sensors and temperature sensors. Among them, the dust sensor adopts a high-precision laser scattering dust meter with a range of 0-100mg / m 3 , real-time monitoring of dust concentration, the humidity sensor uses a high-temperature capacitive humidity transmitter, and the temperature sensor is a Pt100 platinum resistance thermometer;

[0037] For the normalization formula processing of the collected data parameters performed by the pollution index comparison module, the three parameters, dust concentration, humidity and temperature, are first normalized and mapped to the range of 0 to 1. The actual measured dust concentration is marked as D, the actual measured humidity is marked as H, and the actual measured temperature is marked as T. The minimum value of dust concentration is Dmin and the maximum value is Dmax. Since humidity is a percentage, the minimum value is 0 and the maximum value is 100. Therefore, it is directly divided by 100 during normalization. The minimum value of temperature is Tmin and the maximum value is Tmax.

[0038] Dust normalization value Humidity normalized value Temperature normalized value In actual applications, if the measured value exceeds the preset range, the normalized value will be limited to 0 or 1. For example, if the dust concentration is less than Dmin, Dnorm = 0; if the dust concentration is greater than Dmax, Dnorm = 1. The same applies to humidity and temperature.

[0039] The three normalized parameters are weighted and summed according to the given weights to obtain the comprehensive pollution index CPI, where the weights are dust α, humidity β, and temperature γ, and they satisfy: α + β + γ = 1. The comprehensive pollution index calculation formula is CPI = Dnorm * α + Hnorm * β + Tnorm * γ, where α = 0.6, β = 0.3, and γ = 0.1;

[0040] If the CPI rises rapidly for three consecutive times, for example, each time the increase exceeds 0.1, the dust weight α is temporarily increased to 0.8, and other weights are adjusted to keep the total at 1. The adjustment method is as follows: Assuming the original weight vector is α:β:γ=0.6:0.3:0.1, when the dust weight needs to be increased to 0.8, the remaining weight 0.2 is distributed to humidity and temperature according to the original ratio β:γ=3:1, and the calculated value is β=0.15 and γ=0.05. The dynamic weight adjustment can be set to a duration, such as maintaining it for 1 hour after the adjustment, or until the CPI drops below the safety threshold and then restoring the original weight;

[0041] The obtained CPI value is then compared with the stored comprehensive pollution index threshold K. The CPI is in the range of 0 to 1. A larger value indicates a higher pollution load. The minimum value 0 indicates that all parameters are at the lower limit of the range, and the maximum value 1 indicates that all parameters are at the upper limit of the range. When CPI>K, a steering control signal is generated. When CPI≤K, no signal is generated.

[0042] When the dual-line purification switching module receives the steering control signal and the passive steering signal, it controls the motor in the transmission assembly 902 on the housing 901 side to operate in real time, changing the communication path on the side of the traditional sealing rotary disk 903, similar to rotating from the side of the through hole 1 904 to the side of the through hole 2 905, thus completing the industrial gas path adjustment;

[0043] As the original path of the industrial gas is closed in the multi-component laser gas analyzer, the backwash device in the filter mechanism 12 in the control path is operated, and the self-cleaning of the filter mechanism 12 on the original path is completed without affecting the normal detection of the multi-component laser gas analyzer;

[0044] like Figure 4 As shown, through hole 1 904 and through hole 2 905 are connected and installed on their sides, respectively. A compression condensation assembly 10 is provided on the side of the jacket 11. The compression condensation assembly 10 controls the temperature of the inner wall of the jacket 11, so that the high-temperature and high-humidity gas condenses on the wall of the jacket 11, completing the cooling of the industrial gas. At the same time, the condensed water droplets flow back into the shell 901 through the pipe inside the jacket 11, and are finally discharged through the drain port 907 at the bottom of the shell 901.

[0045] When the filter mechanism 12 is backwashed and cleaned, Figure 5 and Figure 7 As shown, filter elements 122 are installed in the main filter cartridge 121 and the auxiliary filter cartridge 126. The flue gas after preliminary cooling enters the main filter cartridge 121 from the bottom, and the flue gas intercepted by the outside of the filter element 122 flows out from the top of the filter element 122, and then is discharged into the laser gas analysis mechanism 3 through the pipeline;

[0046] The entire laser gas analysis mechanism 3 is as follows Figure 3 As shown, by setting up a detection pipe 301, a laser diode in a laser emitting unit 302 is used to emit a tunable laser of a specific wavelength, the wavelength of which matches the absorption spectrum of the target gas, and a detector in a receiving detection unit 303 receives the modulated transmitted light signal, extracts the second harmonic component through a lock-in amplifier, and sends it to the control panel 2 on the portable box 1 after processing by a signal processing unit 304;

[0047] Upon receiving the steering control signal, the pulse spray assembly is started, and the non-working filter element 122 is cleaned from the inside out through the back-blowing pipe 123. At the same time, the valve on the industrial flue gas pipeline is closed to avoid affecting the normal back-blowing work. The discharged dust is actively extracted and discharged through the dust exhaust pipe 125 on the main filter cartridge 121. By efficiently pre-treating the discharged flue gas, two independent pipelines are set for control. When one pre-treatment pipeline is working, the other pipeline is automatically cleaned, and they are independently distinguished and do not affect each other, thereby improving the risk resistance of the entire multi-component laser gas analyzer.

[0048] The entire filtering mechanism 12 is also provided with an alarm box 124. Considering the limited backwash cleaning effect of the filter element 122 and to avoid the problem of pipeline switching back and forth when the comprehensive pollution index is continuously greater than the set threshold, the alarm box 124 is provided with a pressure difference monitoring module and an alarm module;

[0049] Among them, the pressure difference monitoring module is used to obtain the pressure difference data between the main filter cartridge 121 and the auxiliary filter cartridge 126 based on the inside and outside of the filter element 122 per unit time, and feed it back to the alarm module. The alarm module is used to compare the pressure difference data with the stored pressure difference threshold. When the pressure difference value on both sides is greater than the pressure difference threshold, a passive steering signal is generated and sent to the dual-line purification switching module. At this time, the dual-line purification switching module will control the flow line steering only after receiving the two signals;

[0050] When the steering control signal and the passive steering signal are received, the pressure difference on both sides of the filter element 122 in the filter cartridge after the path is adjusted is still greater than the storage pressure difference threshold. At this time, an alarm signal is generated, indicating that the backwash cleaning is ineffective and the filter element 122 is seriously blocked. It is impossible to improve the flue gas cleaning effect by replacing the flow purification path. In rare cases, there is a problem of filter element 122 being damaged.

[0051] At this time, by directly detecting the pressure difference on both sides, if the pressure difference does not change for a long time, an alarm signal will be triggered to remind the operator to check the filter element 122. If no steering control signal is generated, but a passive steering signal is generated, the entire dual-line purification switching module will still switch the path;

[0052] like Figure 1 As shown, the extractive laser gas analyzer is integrated using a portable box 1. A heat dissipation port 1 7 is provided at the rear of the portable box 1, and heat dissipation ports 2 8 are provided on both sides. A four-core aviation plug 6 is installed at the same time, and external power supply is provided. The power supply voltage can use AC 220V or DC24V, and the data output is output through 485 / 4-20mA.

[0053] The above contents are merely examples and explanations of the structure of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the claims, they shall fall within the scope of protection of the present invention.

[0054] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0055] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to specific embodiments. Obviously, many modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A multi-component laser gas analyzer based on front-end preprocessing, comprising a portable box (1), characterized in that: A control panel (2) is provided in the portable box (1), a laser gas analysis mechanism (3) is installed in the portable box (1) and at the bottom of the control panel (2), and an adaptive pre-processing mechanism (9) is installed on the side of the laser gas analysis mechanism (3); The adaptive pre-processing mechanism (9) comprises a housing (901), a sealing rotary disc (903), a first through hole (904), a second through hole (905) and a switching control box (906); the housing (901) is fixedly mounted in the portable box (1), and a transmission assembly (902) is mounted on the side of the housing (901); A sealing rotary disc (903) is movably connected in the housing (901), and the output end of the motor installed in the transmission assembly (902) is fixed to the sealing rotary disc (903). A through hole 1 (904) and a through hole 2 (905) are opened on one side of the housing (901), and the through hole 1 (904) and the through hole 2 (905) are connected to the housing (901); A switching control box (906) is fixed to one side of the shell (901) by bolts, and a drain outlet (907) is provided at the bottom of the shell (901). The switching control box (906) includes a front-end data acquisition module, a pollution index comparison module and a dual-pipeline purification switching module. A protective sleeve (11) is fixed on one side of the through hole 1 (904) and the through hole 2 (905), and a filtering mechanism (12) is installed on the top of the protective sleeve (11).

2. The multi-component laser gas analyzer based on front-end preprocessing according to claim 1, characterized in that: The front-end data acquisition module is used to obtain the dust concentration, humidity and temperature in the exhaust gas in real time, and sends the collected data to the pollution index comparison module. The pollution index comparison module processes the collected data parameters according to a normalization formula to obtain a comprehensive pollution index, and compares it with a stored threshold to generate a steering control signal and send it to the dual-pipeline purification switching module. The dual-pipeline purification switching module is used for motor steering control on the transmission component (902).

3. The multi-component laser gas analyzer based on front-end preprocessing according to claim 2, characterized in that: The laser gas analysis mechanism (3) comprises a detection pipe (301), a laser emitting unit (302), a receiving detection unit (303) and a signal processing unit (304); the detection pipe (301) is fixed to the inner wall of the bottom of the portable box (1); the laser emitting unit (302) is provided on one side of the detection pipe (301); the receiving detection unit (303) is provided on the other side; the signal processing unit (304) is installed on the receiving detection unit (303); and the signal processing unit (304) is electrically connected to the control panel (2).

4. The multi-component laser gas analyzer based on front-end preprocessing according to claim 3 is characterized in that: An air outlet pipe (4) and an air inlet pipe (5) are provided at the rear of the portable box (1), and one end of the air inlet pipe (5) is connected to the top of the shell (901), and one end of the air outlet pipe (4) is connected to the detection pipe (301) in the laser gas analysis mechanism (3).

5. The multi-component laser gas analyzer based on front-end preprocessing according to claim 4 is characterized in that: A compression condensation component (10) is installed on the side of the sheath (11), a heat dissipation port 2 (8) is provided on the portable box (1) and located on the side of the compression condensation component (10), a heat dissipation port 1 (7) is symmetrically provided on the rear side of the portable box (1), and a four-core aviation plug (6) is provided on the portable box (1) and located on the side of the heat dissipation port 1 (7).

6. The multi-component laser gas analyzer based on front-end preprocessing according to claim 1, characterized in that: The filtering mechanism (12) comprises a main filter cartridge (121), an auxiliary filter cartridge (126), a filter core (122) and a backflush pipe (123); the main filter cartridge (121) and the auxiliary filter cartridge (126) are respectively installed on the top of the jacket (11); the filter core (122) is placed in the main filter cartridge (121) and the auxiliary filter cartridge (126); the backflush pipe (123) is provided on the main filter cartridge (121) and the auxiliary filter cartridge (126) inside the filter core (122); and a dust exhaust pipe (125) is fixed to the side walls of the main filter cartridge (121) and the auxiliary filter cartridge (126).

7. The multi-component laser gas analyzer based on front-end preprocessing according to claim 6, characterized in that: The filtering mechanism (12) further comprises an alarm box (124), the alarm box (124) being installed on the top of the main filter cartridge (121) and the auxiliary filter cartridge (126), and a pressure difference monitoring module and an alarm module being installed in the alarm box (124); The pressure difference monitoring module is used to obtain the pressure difference data between the main filter cartridge (121) and the auxiliary filter cartridge (126) based on the inside and outside of the filter element (122) within a unit time, and feed it back to the alarm module. The alarm module is used to compare the pressure difference data with the stored pressure difference threshold value, generate a passive steering signal and send it to the dual-line purification switching module, and directly generate an alarm signal to remind the replacement of the filter element (122).

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