Two-channel in-situ detection system

Abstract

The invention provides a dual-channel in-situ detection system, and relates to the technical field of atmospheric environmental chemistry and analytical chemistry. The first absorption unit is arranged in the smog chamber and is configured to absorb gaseous volatile organic compounds from the outside atmosphere by utilizing first absorption liquid circularly flowing in the first absorption unit to obtain a first sample to be detected; the first detection assembly is communicated with the plurality of liquid outlets of the first absorption unit and is configured to receive and detect a first sample to be detected; the second absorption unit is arranged in the smog chamber and is configured to absorb gaseous volatile organic compounds and volatile organic compound particles from the outside atmosphere by using second absorption liquid circularly flowing in the second absorption unit to obtain a second sample to be detected; and the second detection assembly is communicated with the plurality of liquid outlets of the second absorption unit and is configured to receive and detect a second sample to be detected.

Description

Technical Field

[0001] This disclosure relates to the technical fields of atmospheric environmental chemistry and analytical chemistry, and more specifically, to a dual-channel in-situ detection system. Background Technology

[0002] Volatile organic compounds (VOCs) in the atmosphere are significant influencing factors of tropospheric chemical processes and environmental health, attracting considerable attention due to their complex chemical reaction pathways and potential impacts on the environment and human health. VOCs include hydrocarbons, alcohols, aldehydes, and esters, primarily originating from natural and anthropogenic activities such as traffic emissions, industrial production, coal combustion, and the use of VOCs. These compounds undergo complex chemical reactions in the atmosphere with nitrogen oxides and OH radicals through photochemical reactions, producing secondary organic aerosols (SOA) and ozone (O3), which significantly impact secondary air pollution, climate change, and human health. Furthermore, due to their toxicity and irritant properties, VOCs have carcinogenic, teratogenic, and mutagenic effects on organisms. Current environmental monitoring and analysis methods and standards focus on VOCs including aromatic hydrocarbons, halogenated hydrocarbons, chlorobenzenes, and phenols.

[0003] Accurate detection of atmospheric volatile organic compounds (VOCs) is crucial for elucidating the mechanisms of tropospheric atmospheric chemical reactions, assessing regional environmental pollution, and understanding global climate change. Therefore, accurate detection of atmospheric VOCs has significant scientific and practical value. However, current sampling methods and analytical techniques suffer from several limitations. Traditional methods, such as gas chromatography (GC), suffer from wall losses due to adsorption of high-viscosity VOCs in the tubing and container, leading to a systematic underestimation of target analyte concentrations. Offline methods (such as gas chromatography-mass spectrometry (GC-MS)) offer high detection accuracy but suffer from poor timeliness and high operating costs. Online technologies (such as proton transfer reaction mass spectrometry / PTR-MS and Fourier transform infrared spectroscopy / FTIR), while improving real-time performance, have drawbacks including isomer recognition blind spots, lack of gas / partic phase differentiation capabilities, and insufficient equipment economics. These issues can lead to inaccurate quantification of important secondary aerosol precursors, particularly intermediates like methylglyoxal, and negatively impact the accurate explanation of the overall atmospheric chemical mechanisms. Summary of the Invention

[0004] To address at least one of the technical problems in the prior art, embodiments of this disclosure provide a dual-channel in-situ detection system capable of accurately measuring various volatile organic compounds in the external atmosphere.

[0005] This disclosure provides a dual-channel in-situ detection system, comprising: a smoke chamber; a first absorption unit disposed within the smoke chamber and configured to absorb gaseous volatile organic compounds from the external atmosphere using a first absorbent liquid circulating within the first absorption unit to obtain a first test sample; a first detection component connected to a plurality of liquid outlets of the first absorption unit and configured to receive and detect the first test sample; a second absorption unit disposed within the smoke chamber and configured to absorb gaseous volatile organic compounds and volatile organic compound particles from the external atmosphere using a second absorbent liquid circulating within the second absorption unit to obtain a second test sample; and a second detection component connected to a plurality of liquid outlets of the second absorption unit and configured to receive and detect the second test sample.

[0006] According to some embodiments of this disclosure, both the first absorption unit and the second absorption unit include: a housing; two spiral tubes connected in sequence and disposed within the housing; the air inlet of each spiral tube is configured to receive at least one of the gaseous volatile organic compounds and the volatile organic compound particles; the liquid inlet of each spiral tube is configured to receive either the first absorbent liquid or the second absorbent liquid, such that the first absorbent liquid or the second absorbent liquid absorbs at least one of the gaseous volatile organic compounds and the volatile organic compound particles within the spiral tube; and the liquid outlet of each spiral tube is configured to discharge either the first test sample or the second test sample.

[0007] According to some embodiments of this disclosure, both the first absorption unit and the second absorption unit further include an absorbent supply mechanism, wherein the outlet of the absorbent supply mechanism is connected to the inlet of the spiral tube, and the absorbent supply mechanism is configured to supply the first absorbent or the second absorbent to the spiral tube.

[0008] According to some embodiments of this disclosure, there is an accommodating space between the housing and the two spiral tubes. The first absorption unit and the second absorption unit both further include a circulating water supply mechanism connected to the housing and configured to supply ultrapure water to the accommodating space to keep the spiral tubes warm, so that the spiral tubes can adapt to different ambient temperatures.

[0009] According to some embodiments of this disclosure, the first absorption unit further includes a filter device, one end of which is connected to the outside atmosphere, and the other end of which is connected to the air inlet of the spiral tube. The filter device is provided with a fiber membrane, which is suitable for collecting volatile organic compound particles from the outside atmosphere on the fiber membrane by means of filtration and adsorption, so that the gaseous volatile organic compounds enter the spiral tube.

[0010] According to some embodiments of this disclosure, both the first detection component and the second detection component include a liquid flow control device, wherein the inlet of the liquid flow control device is connected to the outlet of the spiral tube and is configured to adjust the flow rate of the first test sample or the second test sample.

[0011] According to some embodiments of this disclosure, both the first detection component and the second detection component further include: a separation component connected to the outlet of the liquid flow control device, configured to split the first test sample or the second test sample in time sequence and collect them separately.

[0012] According to some embodiments of this disclosure, both the first detection component and the second detection component further include a detection device, which is any one of the following: gas chromatography-mass spectrometry, liquid chromatography, and liquid chromatography-electrostatic track trap high-resolution mass spectrometry.

[0013] According to some embodiments of this disclosure, the dual-channel in-situ detection system further includes: two gas recovery devices, which are respectively connected to the gas outlet of the spiral tube belonging to the first absorption unit and the gas outlet of the spiral tube belonging to the second absorption unit, and are configured to pump the external atmosphere after being absorbed by the first absorption liquid and the second absorption liquid back into the external environment.

[0014] According to some embodiments of this disclosure, the ratio of the flow rate of the outside atmosphere after absorption by the first absorbent liquid to the flow rate of the first test sample is 1, and the ratio of the flow rate of the outside atmosphere after absorption by the second absorbent liquid to the flow rate of the second test sample is 1.

[0015] According to the dual-channel in-situ detection system of this disclosure, a first absorption unit is disposed in a smoke chamber. The first absorption unit absorbs gaseous volatile organic compounds from the outside atmosphere using a first absorbent liquid circulating within the first absorption unit to obtain a first test sample. A first detection component is connected to multiple outlets of the first absorption unit, and the first detection component receives and detects the first test sample. A second absorption unit is disposed in a smoke chamber. The second absorption unit absorbs both gaseous volatile organic compounds and volatile organic compound particles from the outside atmosphere using a second absorbent liquid circulating within the second absorption unit to obtain a second test sample. A second detection component is connected to multiple outlets of the second absorption unit, and the second detection unit receives and detects the second test sample. The dual-channel in-situ detection system can be directly placed in the outside atmosphere for online detection and can accurately measure multiple volatile organic compounds in the outside atmosphere. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a dual-channel in-situ detection system according to an embodiment of the present disclosure;

[0017] Figure 2 This is a cross-sectional view of a housing and two sequentially connected spiral tubes according to an illustrative embodiment of the present disclosure;

[0018] Figure 3 According to an illustrative embodiment of this disclosure, the concentration of ammonium sulfate seed aerosol is 240 μg / m³. 3 Figure showing the results of the smoke chamber experiment;

[0019] Figure 4 This is a box plot comparing the absorption efficiency of four sampling pipelines for target volatile organic compounds under different gas-liquid flow rate ratios according to an illustrative embodiment of the present disclosure.

[0020] Figure 5 This is a flowchart of a dual-channel in-situ sampling method for gaseous volatile organic compounds and volatile organic compound particles according to an illustrative embodiment of the present disclosure;

[0021] Figure 6 This is a graph showing the results of an experiment on the concentration gradient absorption of acetone using a spiral tube according to an illustrative embodiment of this disclosure;

[0022] Figure 7 This is a graph showing the results of a concentration gradient absorption experiment of 1,3,5-trimethylbenzene using a spiral tube according to an illustrative embodiment of the present disclosure.

[0023] The meanings of the reference numerals in the attached figure are as follows:

[0024] 1. Smoke box;

[0025] 2. Shell;

[0026] 3. Spiral tube;

[0027] 4. Absorbent liquid supply mechanism;

[0028] 5. Circulating water supply system;

[0029] 6. Filtration device;

[0030] 7. Liquid flow control device;

[0031] 8. Diverter valve;

[0032] 9. Sample vials;

[0033] 10. Detection device;

[0034] 11. Drying tube;

[0035] 12. Electronic air flow meter;

[0036] 13. Oil-free vacuum pump;

[0037] 14. Electrical controller;

[0038] 15. Light-proof enclosure. Detailed Implementation

[0039] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0040] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0041] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0042] When using expressions such as "at least one of A, B, and C," the expression should generally be interpreted in accordance with the meaning commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, and C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.). When using expressions such as "at least one of A, B, or C," the expression should generally be interpreted in accordance with the meaning commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, or C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.).

[0043] To improve detection accuracy, according to one aspect of the inventive concept of this disclosure, a dual-channel in-situ detection system is provided. A first absorption unit is disposed within a smoke chamber. The first absorption unit absorbs gaseous volatile organic compounds (VOCs) from the external atmosphere using a first absorbent liquid circulating within it, obtaining a first test sample. A first detection component is connected to multiple outlets of the first absorption unit, receiving and detecting the first test sample. A second absorption unit is disposed within the smoke chamber. The second absorption unit simultaneously absorbs gaseous VOCs and VOC particles from the external atmosphere using a second absorbent liquid circulating within it, obtaining a second test sample. A second detection component is connected to multiple outlets of the second absorption unit, receiving and detecting the second test sample. This dual-channel in-situ detection system can be directly placed in the external atmosphere for online detection and can accurately measure various VOCs in the external atmosphere.

[0044] Figure 1 This is a schematic diagram of a dual-channel in-situ detection system according to an embodiment of the present disclosure.

[0045] A dual-channel in-situ detection system is provided according to embodiments of this disclosure, such as... Figure 1 As shown, the system includes a smoke chamber 1, a first absorption unit, a first detection component, a second absorption unit, and a second detection component. The first absorption unit is disposed within the smoke chamber 1 and is configured to absorb gaseous volatile organic compounds (VOCs) from the external atmosphere using a first absorbent liquid circulating within the unit, thereby obtaining a first test sample. The first detection component is connected to multiple outlets of the first absorption unit and is configured to receive and detect the first test sample. The second absorption unit is also disposed within the smoke chamber 1 and is configured to absorb gaseous VOCs and VOC particles from the external atmosphere using a second absorbent liquid circulating within the unit, thereby obtaining a second test sample. The second detection component is connected to multiple outlets of the second absorption unit and is configured to receive and detect the second test sample.

[0046] According to embodiments of this disclosure, the first absorption unit and the second absorption unit are capable of absorbing gaseous volatile organic compounds in the external atmosphere, including but not limited to cyclohexane, n-pentane, isoprene, limonene, propylene, toluene, mesitylene, propionaldehyde, n-butyraldehyde, acetone, and cyclohexanone.

[0047] According to embodiments of this disclosure, the first absorbent and the second absorbent can be selected based on the chemical properties (polarity, molecular weight, volatility, etc.) of at least one of the gaseous volatile organic compounds and volatile organic compound particles to be tested. The first absorbent and the second absorbent include, but are not limited to, methanol, acetonitrile, and n-hexane.

[0048] According to embodiments of this disclosure, Figure 1 The A pathway in the diagram is the gas phase pathway. Figure 1 The B pathway in the diagram is the gas-particle phase pathway. Figure 1 The A pathway includes a first absorption unit and a first detection component. Figure 1 The B pathway includes a second absorption unit and a second detection component.

[0049] According to an embodiment of this disclosure, a first absorption unit is disposed within a smoke chamber 1. The first absorption unit absorbs gaseous volatile organic compounds from the outside atmosphere using a first absorbent liquid circulating within the first absorption unit to obtain a first test sample. A first detection component is connected to multiple outlets of the first absorption unit, and the first detection component receives and detects the first test sample. A second absorption unit is disposed within a smoke chamber 1. The second absorption unit simultaneously absorbs gaseous volatile organic compounds and volatile organic compound particles from the outside atmosphere using a second absorbent liquid circulating within the second absorption unit to obtain a second test sample. A second detection component is connected to multiple outlets of the second absorption unit, and the second detection unit receives and detects the second test sample. The dual-channel in-situ detection system can be directly placed in the outside atmosphere for online detection and can accurately measure multiple volatile organic compounds in the outside atmosphere, thus improving detection accuracy.

[0050] Figure 2 This is a cross-sectional view of a housing and two sequentially connected spiral tubes according to an illustrative embodiment of the present disclosure.

[0051] According to embodiments of this disclosure, such as Figure 2 As shown, both the first absorption unit and the second absorption unit include a housing 2 and two sequentially connected spiral tubes 3. The two sequentially connected spiral tubes 3 are disposed inside the housing 2. The air inlet G of each spiral tube 3 is configured to receive at least one of gaseous volatile organic compounds and volatile organic compound particles. The liquid inlets D1 and D2 of the spiral tube 3 are configured to receive either a first absorbent or a second absorbent, such that the first absorbent or the second absorbent absorbs at least one of gaseous volatile organic compounds and volatile organic compound particles within the spiral tube 3. The liquid outlets E1 and E2 of the spiral tube 3 are configured to discharge either a first test sample or a second test sample.

[0052] According to an embodiment of this disclosure, the second absorption unit is arranged in parallel with the first absorption unit, and the two spiral tubes 3 connected in sequence can be glass spiral tubes.

[0053] According to an embodiment of the present disclosure, in two sequentially connected spiral tubes 3, the spiral tube 3 at the front end contains 20 spirals, and the spiral tube 3 at the rear end contains 7 spirals.

[0054] According to embodiments of this disclosure, taking the spiral tube 3 of the first absorption unit as an example, the spiral tube 3 located at the front end of the first absorption unit is suitable for absorbing gaseous volatile organic compounds from the outside atmosphere using a first absorbent liquid circulating within the spiral tube 3. The spiral tube 3 located at the rear end of the first absorption unit is suitable for completely absorbing gaseous volatile organic compounds (the portion of gaseous volatile organic compounds not absorbed by the spiral tube 3 at the front end) from the outside atmosphere using the first absorbent liquid circulating within the spiral tube 3, based on the penetration of the gaseous volatile organic compounds into the spiral tube 3 at the front end. The spiral tube 3 of the second absorption unit is similar to that of the spiral tube 3 of the first absorption unit.

[0055] According to embodiments of this disclosure, both the first absorption unit and the second absorption unit further include a light-shielding chamber 15, with the housing 2 and two sequentially connected spiral tubes 3 disposed within the light-shielding chamber 15. The surface of the chamber is made of a light-shielding material, and a reflective film is attached to the outside of the light-shielding chamber 15 to prevent sunlight exposure, avoid possible photolysis or photosensitive substance reactions, and maintain the chemical stability of at least one of the gaseous volatile organic compounds and volatile organic compound particles to be tested as much as possible. The light-shielding chamber 15 can be a Teflon chamber. The absorption of at least one of the gaseous volatile organic compounds and volatile organic compound particles by the first or second absorption liquid within the spiral tube 3 is carried out under light-free conditions. The first and second test samples are guided to the subsequent liquid flow control device 7 (described in detail below) through outlets E1 and E2.

[0056] According to the embodiments of this disclosure, the housing 2 belonging to the first absorption unit, the two spiral tubes 3 connected in sequence, the filter device 6, and the light-shielding box 15 are disposed inside the smoke box 1, and the housing 2 belonging to the second absorption unit, the two spiral tubes 3 connected in sequence, and the light-shielding box 15 are disposed inside the smoke box 1.

[0057] According to embodiments of this disclosure, the first absorption unit and the second absorption unit can be placed at different sampling sites in the external environment and temperature and light can be controlled to adapt to different in-situ sampling environments, greatly reducing wall loss and chemical reaction problems that may occur during the transfer and processing of gaseous volatile organic compounds.

[0058] According to embodiments of this disclosure, both the first absorption unit and the second absorption unit further include an absorbent supply mechanism 4. The outlet of the absorbent supply mechanism 4 is connected to the inlet D1 and inlet D2 of the spiral tube 3. The absorbent supply mechanism 4 is configured to supply the first absorbent or the second absorbent into the spiral tube 3.

[0059] According to an embodiment of this disclosure, the absorbent supply mechanism 4 supplies a first absorbent to the spiral tube 3 belonging to the first absorption unit, so that the first absorbent circulates within the spiral tube 3 to absorb gaseous volatile organic compounds from the outside atmosphere.

[0060] According to an embodiment of this disclosure, the absorbent supply mechanism 4 supplies a second absorbent to the spiral tube 3 belonging to the second absorption unit, so that the second absorbent circulates within the spiral tube 3 to absorb gaseous volatile organic compounds and volatile organic compound particles from the outside atmosphere.

[0061] According to an embodiment of the present disclosure, there is an accommodating space between the housing 2 and the two spiral tubes 3. The first absorption unit and the second absorption unit both further include a circulating water supply mechanism 5. The circulating water supply mechanism 5 is connected to the housing 2 and is configured to supply ultrapure water to the accommodating space to keep the spiral tubes 3 warm, so that the spiral tubes 3 can adapt to different ambient temperatures.

[0062] According to embodiments of this disclosure, the first absorption unit and the second absorption unit are placed at different sampling sites in the external atmosphere to simulate different sampling environment temperatures. The circulating water supply mechanism 5 is configured to supply ultrapure water (constant-temperature circulating water) into the containment space to insulate the spiral tube 3, thereby maintaining a stable sampling temperature. The circulating water supply mechanism 5 is also configured to adjust the temperature of the ultrapure water, allowing the spiral tube 3 to adapt to different sampling environment temperatures.

[0063] According to an embodiment of this disclosure, the first absorption unit further includes a filter device 6. One end of the filter device 6 is connected to the outside atmosphere, and the other end of the filter device 6 is connected to the air inlet G of the spiral tube 3. A fiber membrane is provided on the filter device 6, which is suitable for collecting volatile organic compound particles from the outside atmosphere on the fiber membrane by means of filtration and adsorption, so that the gaseous volatile organic compounds enter the spiral tube 3.

[0064] According to embodiments of this disclosure, the filtration device 6 can be a gas filter head, and the fiber membrane includes, but is not limited to, a quartz filter membrane and a polytetrafluoroethylene gas phase filter membrane.

[0065] According to embodiments of this disclosure, the gas filter head contains a quartz filter membrane with a pore size of 0.45 μm. This quartz filter membrane acts as a particulate filter, filtering the gaseous volatile organic compounds entering the spiral tube 3 to obtain a pure gas-phase absorption sample (gaseous volatile organic compounds). Cutting heads of different particle sizes can be added to the front end of the gas filter head as needed to sieve particles of different sizes. By adjusting the pore size of the filter membrane, the first detection component and the second detection component can respectively detect and analyze the composition of particles of different sizes in the first and second test samples.

[0066] Figure 3 According to an illustrative embodiment of this disclosure, the concentration of ammonium sulfate seed aerosol is 240 μg / m³. 3 The results of the smoke chamber experiment are shown in the figure.

[0067] According to embodiments of this disclosure, in order to verify the gas-particle phase separation efficiency of the dual-channel in-situ detection system, at a depth of 2m... 3 Two experiments were conducted in the smoke chamber containing different concentrations of ammonium sulfate seed aerosols, such as... Figure 3 As shown, Figure 3 The concentration of ammonium sulfate seed aerosol was 240 μg / m³. 3 Gas-particle phase pathway ( Figure 1 The B pathway in the gas phase has a capture efficiency of 102.2% for ammonium sulfate aerosols, which is located in the gas phase pathway. Figure 1 The ammonium sulfate concentration detected on the quartz filter membrane at the front end of the A-channel (in the gas phase path) was less than 5% of the total concentration, indicating that the gas phase path effectively prevented the penetration of particulate phase. The particulate phase results measured by the dual-channel in-situ detection system were highly consistent with the reference values ​​of the scanning electromobility particle size spectrometer (SMPS), with a deviation within 10%. The gas phase path results were also comparable to the SMPS concentration (approximately 104%). This dual-channel in-situ detection system effectively distinguished and captured particulate phase substances through the quartz filter membrane, while maintaining good cleanliness in the gas phase path. Compared to the potential pipeline losses of SMPS, this in-situ sampling method showed significant advantages.

[0068] According to embodiments of this disclosure, both the first detection component and the second detection component include a liquid flow control device 7. The inlet of the liquid flow control device 7 is connected to the outlets E1 and E2 of the spiral tube 3, and the liquid flow control device 7 is configured to regulate the flow rate of the first test sample or the second test sample.

[0069] According to embodiments of this disclosure, the liquid flow control device 7 can be a peristaltic pump. The inlet of the peristaltic pump is connected to the outlet E1 and outlet E2 of the spiral tube 3. The peristaltic pump is suitable for providing power to pump the first absorbent or the second absorbent into the spiral tube 3 to realize the flow of liquid. The flow rate of the first test sample or the second test sample can be adjusted by adjusting the rotation speed. The flow rate of the first test sample or the second test sample is calibrated by testing before sampling and before each replacement of the peristaltic tube.

[0070] According to embodiments of this disclosure, both the first detection component and the second detection component further include a separation component. The separation component is connected to the outlet of the liquid flow control device 7, and is configured to split the first test sample or the second test sample in chronological order and collect them separately.

[0071] According to embodiments of this disclosure, the separation component is suitable for preserving a first test sample or a second test sample and transferring it to a laboratory for qualitative and quantitative analysis.

[0072] According to embodiments of this disclosure, the separation assembly includes a split valve 8 and multiple sample vials 9. The split valve 8 is configured to sequentially collect either a first or a second sample by timed sampling. The split valve 8 can be a twelve-channel split valve, and the sample vials 9 can be liquid chromatography vials. The inlet of the twelve-channel split valve is connected to the outlet of the liquid flow control device 7, and the outlet of each channel of the twelve-channel split valve is connected to a 2ml liquid chromatography vial. A channel is set to be changed every 5 minutes to achieve automated sampling of either the first or second sample.

[0073] According to embodiments of this disclosure, both the first detection component and the second detection component further include a detection device 10, which is any one of the following: a gas chromatography-mass spectrometry system, a liquid chromatograph, and a liquid chromatography-electrostatic field track trap high-resolution mass spectrometer.

[0074] According to embodiments of this disclosure, the detection device 10 includes, but is not limited to, gas chromatography-mass spectrometry (GC / MS), high performance liquid chromatography (HPLC), and liquid chromatography-electrostatic field orbital trap high resolution mass spectrometry (Orbitrap–LC / MS).

[0075] In one illustrative embodiment, the detection device 10 is connected to multiple sample vials 9. When the detection device 10 is a gas chromatography-mass spectrometry (GC-MS) instrument, the GC-MS instrument is suitable for first performing GC-MS separation on a first or second sample to be tested, and then detecting the separated target compound.

[0076] In one illustrative embodiment, the detection device 10 includes a derivatization section, a high-performance liquid chromatography (HPLC) separation section, and a detection section. The sample vial 9 is connected to the derivatization section, which is specifically a 2,4-dinitrophenylhydrazine (DNPH) solution. This solution is mixed with either the first or second test sample and derivatized at 70°C for 3 hours to detect carbonyl-based volatile organic compounds. The HPLC separation section can be performed using a high-performance liquid chromatograph (HPLC). The detection section can be performed using an ultraviolet (UV) detector, which is suitable for detecting the separated target compound.

[0077] In one illustrative embodiment, the detection device 10 includes a liquid chromatography-mass spectrometry separation section and a liquid chromatography-mass spectrometry detection section. The sample vial 9 is connected to the liquid chromatography-mass spectrometry separation section, and the liquid chromatography-mass spectrometry detection section is suitable for detecting the separated target compound, specifically a liquid chromatography-electrostatic field orbital trap high-resolution mass spectrometer (Orbitrap–LC / MS).

[0078] According to embodiments of this disclosure, when the concentration of gases in the ambient atmosphere is low, a circulation system can be used to enrich organic matter. Specifically, the outlets E1 and E2 of the spiral tube 3 are directly connected to the absorption liquid injection bottle for recycling of either the first or second absorption liquid until the concentration of at least one of the gaseous volatile organic compounds and volatile organic compound particles reaches the target level, thereby increasing the absolute concentration of the target volatile organic compound (at least one of the gaseous volatile organic compounds and volatile organic compound particles). The first or second absorption liquid after capturing the target volatile organic compound can be used for different gas chromatography and liquid chromatography analysis methods. For example, methanol can be preferentially used as an absorption liquid for gas chromatography-mass spectrometry (GC / MS) analysis. Acetonitrile is used for the later complexation of dinitrophenylhydrazine (DNPH) for high performance liquid chromatography (HPLC) determination, mainly for the detection of aldehydes and ketones. More complex volatile organic compound samples can also be sent to a liquid chromatography-electrostatic field orbital trap high resolution mass spectrometer (Orbitrap–LC / MS) for detection.

[0079] According to embodiments of this disclosure, by comparing the analysis results of pathway A and pathway B, the species and concentration characteristics of gaseous volatile organic compounds and volatile organic compound particles are obtained.

[0080] According to embodiments of this disclosure, the dual-channel in-situ detection system further includes two gas recovery devices. The two gas recovery devices are respectively connected to the outlet F of the spiral tube 3 belonging to the first absorption unit and the outlet F of the spiral tube 3 belonging to the second absorption unit. The two gas recovery devices are configured to pump the ambient air, after being absorbed by the first and second absorbent liquids, back into the external environment.

[0081] According to embodiments of this disclosure, a gas recovery device is suitable for regulating the sampling flow rate of at least one of gaseous volatile organic compounds and volatile organic compound particles. Each gas recovery device includes a drying tube 11, an electronic air flow meter 12, and an oil-free vacuum pump 13. The inlet of the drying tube 11 is connected to the outlet F of the spiral tube 3, and the drying tube 11 is filled with molecular sieve particles. The inlet of the electronic air flow meter 12 is connected to the outlet of the drying tube 11. The electronic air flow meter 12 is suitable for ensuring the stability of the flow rate of at least one of gaseous volatile organic compounds and volatile organic compound particles, maintaining a constant flow rate by setting a fixed flow rate, and periodically calibrating the inlet G of the spiral tube 3 using the electronic air flow meter 12. The inlet of the oil-free vacuum pump 13 is connected to the outlet of the electronic air flow meter 12, and the outlet of the oil-free vacuum pump 13 is connected to the outside atmosphere. The oil-free vacuum pump 13 is suitable for providing power for pumping outside atmosphere into the spiral tube 3.

[0082] According to embodiments of this disclosure, the ratio of the flow rate of the external atmosphere after absorption by the first absorbent liquid to the flow rate of the first test sample is 1, and the ratio of the flow rate of the external atmosphere after absorption by the second absorbent liquid to the flow rate of the second test sample is 1.

[0083] According to embodiments of this disclosure, the appropriateness of the ratio (R) between the flow rate of the external atmosphere after absorption by the absorbent and the flow rate of the sample to be tested is crucial for the normal operation of sampling. An excessively high ratio (R) may result in an excessively fast flow rate of the target volatile organic compounds, reducing absorption efficiency and causing breakthrough, thereby underestimating the concentration of the target volatile organic compounds. Conversely, an excessively low ratio (R) may result in a lower concentration of the target volatile organic compounds in the absorbent, even below the instrument's detection limit, thus affecting the measurement results.

[0084] According to embodiments of this disclosure, in order to determine the optimal operating parameters for sampling, the main focus is on the effect of the ratio (R) of the flow rate of the ambient air after absorption by the absorbent to the flow rate of the sample under test on the absorption efficiency of the target volatile organic compounds (VOCs). Experiments were conducted by varying the flow rates of the ambient air after absorption by the absorbent and the sample under test, using representative target compounds (acetone, 1,3,5-trimethylbenzene) for verification, and comparing the performance of different sampling pipelines (spiral tube A1 at the front end of the first absorption unit, spiral tube A2 at the rear end of the first absorption unit; spiral tube B1 at the front end of the second absorption unit, spiral tube B2 at the rear end of the second absorption unit).

[0085] Figure 4 This is a box plot comparing the absorption efficiency of four sampling pipelines for target volatile organic compounds under different gas-liquid flow rate ratios, according to an illustrative embodiment of the present disclosure.

[0086] According to embodiments of this disclosure, such as Figure 4 As shown in Figure (a), both the first and second absorbents were acetonitrile. Acetone, a representative target compound, was used for verification, and the performance of different sampling tubes (spiral tube A1 at the front end of the first absorption unit, spiral tube A2 at the rear end of the first absorption unit; spiral tube B1 at the front end of the second absorption unit, spiral tube B2 at the rear end of the second absorption unit) was compared. Figure 4As shown in Figure (b), the representative target compound 1,3,5-trimethylbenzene was used for verification, and the performance of different sampling tubes (spiral tube A1 at the front end of the first absorption unit, spiral tube A2 at the rear end of the first absorption unit; spiral tube B1 at the front end of the second absorption unit, spiral tube B2 at the rear end of the second absorption unit) was compared. When R = 0.67 (the flow rate of the outside atmosphere after absorption by the absorbent was 0.2 L / min, and the flow rate of the sample was 0.3 mL / min), acetone and 1,3,5-trimethylbenzene were almost completely absorbed by the spiral tube at the front end (the breakthrough concentration of the spiral tube at the rear end was less than 5%). When R = 1.0 (the flow rate of the outside atmosphere after absorption by the absorbent was 0.3 L / min, and the flow rate of the sample was 0.3 mL / min), the absorption was the same as above. Although the absorption efficiencies are similar at both R values ​​(within the error range), the higher atmospheric flow rate after absorption by the absorbent (0.3 L / min) at R=1.0 produces a more significant and easily detectable analytical signal peak (test peak), which is beneficial for improving measurement accuracy. Simultaneously, the absorption efficiency has not yet reached its saturation limit at this point, indicating that this parameter combination provides an adjustment range for practical operation while ensuring efficient absorption. However, when the ratio (R) increases to approximately 1.67 (at an atmospheric flow rate of 0.5 L / min after absorption by the absorbent and a sample flow rate of 0.3 mL / min), the absorption rate of acetone by the front-end spiral tube significantly decreases to approximately 86.6%, and the absorption rate of 1,3,5-trimethylbenzene decreases to 92.5%. This indicates that excessively high atmospheric flow rates after absorption by the absorbent (i.e., excessively large R values) lead to insufficient contact time between the target volatile organic compounds and the absorbent, reducing absorption efficiency. Based on experimental results with different gas-liquid flow rate ratios, this disclosure recommends using a ratio R = 1.0 (i.e., the flow rate of the outside atmosphere after absorption by the absorbent is 0.3 L / min, and the flow rate of the sample is 0.3 mL / min) as the standard sampling parameter. This parameter combination effectively balances high absorption efficiency with good detection signal intensity, ensuring the accuracy and reliability of VOCs sampling. In practical applications, this parameter can be fine-tuned based on the specific target VOCs and the properties of the absorbent.

[0087] According to an embodiment of this disclosure, before sampling, the flow rate of the target volatile organic compound (VOC) at the front end of the spiral tube is calibrated by using a flow meter to test the flow rate at the inlet of the spiral tube. Considering the potential steric hindrance of the target VOC in the spiral tube 3 that may cause velocity loss, parallel tests of the target VOC flow rate are required to accurately record the actual target VOC flow rate, and the electronic air flow meter 12 is adjusted accordingly.

[0088] According to embodiments of this disclosure, the dual-channel in-situ detection system further includes two electrical controllers 14. One of the electrical controllers 14 is electrically connected to the first absorption unit, the first detection component, and a gas recovery device to control the operation of the first absorption unit, the first detection component, and the gas recovery device. The other electrical controller 14 is electrically connected to the second absorption unit, the second detection component, and another gas recovery device to control the operation of the second absorption unit, the second detection component, and the other gas recovery device.

[0089] Figure 5 This is a flowchart of a dual-channel in-situ sampling method for gaseous volatile organic compounds and volatile organic compound particles according to an illustrative embodiment of the present disclosure.

[0090] According to another embodiment of this disclosure, such as Figure 5 As shown, a dual-channel in-situ sampling method for gaseous volatile organic compounds and volatile organic compound particles is provided, which is applicable to the above-mentioned dual-channel in-situ detection system. The dual-channel in-situ sampling method for gaseous volatile organic compounds and volatile organic compound particles includes the following steps S1 to S5.

[0091] Step S1: System preparation.

[0092] According to an embodiment of this disclosure, the electronic air flow meter 12 and the peristaltic pump are respectively set to the desired flow rates. The water temperature of the circulating water supply mechanism 5 is set and circulation is started. The diversion valve 8 and the detection device 10 are activated to enter the system self-test and preparation state.

[0093] Step S2: Capture of target volatile organic compounds in the external atmosphere.

[0094] According to an embodiment of this disclosure, the oil-free vacuum pump 13 and the peristaltic pump are turned on. Outside air enters the spiral tube 3 belonging to the first absorption unit through a gas filter head, and simultaneously enters the spiral tube 3 belonging to the second absorption unit. The absorbent enters the spiral tube 3 through inlet D1 and inlet D2. At least one of the gaseous volatile organic compounds and volatile organic compound particles in the outside air is captured by the absorbent. After absorption by the absorbent, the outside air reaches the drying tube 11 and the electronic air flow meter 12 through the outlet F of the spiral tube 3. Subsequently, the sample to be tested reaches the liquid flow control device 7 through the outlet E1 and outlet E2 of the spiral tube 3.

[0095] Step S3: Collection and loading of the sample to be tested.

[0096] According to the embodiments of this disclosure, the sample to be tested sequentially enters the peristaltic pump, the diversion valve 8, and the sample bottle 9 before being loaded into the detection device 10, thus completing the loading of the sample to be tested.

[0097] Step S4: Detection of the sample to be tested.

[0098] According to embodiments of this disclosure, the collected sample to be tested is loaded into the detection device 10, atmospheric compounds are separated using methods such as gradient elution, and detected using a detector. Simultaneously, the concentration of at least one of gaseous volatile organic compounds and volatile organic compound particles in the absorption liquid is obtained by combining the external standard method. This includes the application of gas chromatography-mass spectrometry (GC / MS), high performance liquid chromatography (HPLC), and liquid chromatography-electrostatic field orbital trap high resolution mass spectrometry (Orbitrap–LC / MS) to achieve accurate detection and analysis of various volatile organic compounds.

[0099] Step S5: Quantitative calculation.

[0100] According to embodiments of this disclosure, the concentration ρ of the target volatile organic compound in the absorbent and the flow rate F of the sample to be tested are used as the basis for determining the concentration. l and the velocity F of the outside atmosphere after absorption by the absorbent liquid g The concentration of atmospheric volatile organic compounds can be calculated using the following formula (1):

[0101] C = ×10 3 (1);

[0102] Where C represents the concentration of the target volatile organic compound in smoke chamber 1, in ppbv. ρ represents the concentration of the target volatile organic compound in the sample to be tested, in mg / L. -1 F l Expressed as the flow rate of the sample to be tested, in mL / min. -1 V m Expressed as the molar volume of gas at the sampling temperature, in L mol. -1 M represents the molar mass of the target volatile organic compound, in g / mol. -1 F g Expressed as the velocity of the outside atmosphere after absorption by the absorbent, in L / min. -1 .

[0103] According to embodiments of this disclosure, accurate quantification of atmospheric volatile organic compounds (VOCs) and their products is crucial for a deeper understanding of the complex reaction mechanisms of air pollution. The in-situ absorption method provided in this disclosure employs a highly efficient spiral tube design, which not only effectively avoids the loss problem of external connecting tubes in traditional methods but also preserves the sample in real time for subsequent detection by various methods. Simultaneously, the spiral tube at the rear end can verify the absorption effect of the absorbent in real time. This method not only has the ability to capture target VOCs in real time but also enables in-situ sampling and separation detection of gaseous and particulate VOCs, avoiding sampling interference. Since the absorbent containing both gaseous and particulate VOCs is suitable for qualitative and quantitative analysis using both gas chromatography and liquid chromatography-mass spectrometry (GC-MS), it allows for a deeper understanding of the transformation and influence mechanisms of atmospheric VOCs in the atmosphere, providing new scientific evidence for the rational assessment of the reactivity and environmental impact of atmospheric VOCs.

[0104] To verify the feasibility and accuracy of this disclosure, three embodiments are provided below. These embodiments demonstrate how the dual-channel in-situ detection system provided in this disclosure performs in-situ sampling and offline analysis of target volatile organic compounds in the external atmosphere through a smoke chamber experiment to determine the concentration of atmospheric volatile organic compounds.

[0105] Example 1: In-situ sampling and detection of gaseous volatile organic compounds

[0106] Acetone, as a simple carbonyl compound, can participate in photochemical reactions in the atmosphere, producing ozone and other minor pollutants, which have a profound impact on atmospheric chemical processes and air quality. 1,3,5-Trimethylbenzene, as a typical aromatic volatile organic compound, is an important secondary aerosol and ozone precursor, exhibiting complex photooxidative degradation pathways and the ability to generate diverse products. Therefore, acetone (colorless and transparent liquid) and 1,3,5-trimethylbenzene (colorless and transparent liquid) were selected as examples for atmospheric simulation experiments in a smog chamber.

[0107] Before the experiment, ensure that the first absorption unit, second absorption unit, first detection component, second detection component, and two gas recovery devices are in normal working order and electrically connected to the two electrical controllers 14. Adjust the operating parameters of each unit in the dual-channel in-situ detection system to ensure the accuracy and repeatability of the experiment. Specifically, the electronic air flow meters 12 in both gas recovery devices are set to a flow rate of 0.3 L / min, the peristaltic pump in the liquid flow control device 7 is set to a flow rate of 0.3 mL / min, and the diversion valve 8 is set to collect one sample every 5 minutes.

[0108] Standard acetone and 1,3,5-trimethylbenzene were precisely added to smoke chamber 1 to prepare simulated environmental gases with acetone gradients of 17.5 ppb and 35 ppb, and simulated environmental gases with 1,3,5-trimethylbenzene gradients of 11 ppb and 28.5 ppb, respectively. The oil-free vacuum pump 13 and the peristaltic pump were started to introduce acetone gas at concentrations of 17.5 ppb and 35 ppb into the first and second absorption units in two separate steps. The design of the spiral tube 3 effectively captured the atmospheric acetone into the absorption liquid. The sample to be tested was mixed with a pre-prepared 2,4-dinitrophenylhydrazine (DNPH) acetonitrile mixed solution in a certain proportion to ensure appropriate derivatization reaction. After absorption and derivatization, the sample vial 9 was sent to a high-performance liquid chromatograph (HPLC) for separation and quantitative analysis to determine the content of the derivatized acetone derivative.

[0109] Two separate absorption units were introduced into the first and second absorption units, simulating atmospheric concentrations of 1,3,5-trimethylbenzene gas at 11 ppb and 28.5 ppb, respectively. The atmospheric 1,3,5-trimethylbenzene was effectively captured in the absorption liquid using a spiral tube (3). The sample to be tested was mixed with a pre-prepared 2,4-dinitrophenylhydrazine (DNPH) acetonitrile solution at a specific ratio to ensure appropriate derivatization. After absorption and derivatization, the sample vial (9) was sent to a gas chromatography-mass spectrometry (GC / MS) instrument for the separation and quantitative analysis of 1,3,5-trimethylbenzene. A standard curve was established using multiple sets of standard solutions to correct and validate the experimental results. By comparing the experimental results with the expected concentrations, the application effect and accuracy of the dual-channel in-situ detection system disclosed herein in the in-situ sampling and offline analysis of gaseous volatile organic compounds were evaluated.

[0110] Figure 6 This is a graph showing the results of an experimental study on the concentration gradient absorption of acetone using a spiral tube according to an illustrative embodiment of this disclosure. Figure 7 This is a graph showing the results of a concentration gradient absorption experiment of 1,3,5-trimethylbenzene using a spiral tube according to an illustrative embodiment of the present disclosure.

[0111] Example 1 verified the absorption performance of the dual-channel helical tube 3 for representative gaseous volatile organic compounds (VOCs). For example... Figure 6 As shown, the overall average absorption rate of acetone in the dual channels is 95.93%, as Figure 7As shown, the overall average absorption rate of 1,3,5-trimethylbenzene in the dual-channel system was 91.67%. The relative deviation between the results measured for acetone in the gas phase pathway (A pathway) and the gas-particle phase pathway (B pathway) was 7.63%, and the relative deviation between the results measured for 1,3,5-trimethylbenzene in the gas phase pathway (A pathway) and the gas-particle phase pathway (B pathway) was 6.39%, indicating that the dual-channel system operates stably and with good consistency.

[0112] The dual-channel in-situ detection system disclosed herein, under simulated laboratory conditions, can achieve efficient capture (absorption rate close to or exceeding 90%) and reliable in-situ sampling analysis of typical gaseous VOCs (such as acetone and 1,3,5-trimethylbenzene) in the atmosphere. The stability (low relative deviation) of the dual-channel design ensures the reliability of the measurement results, providing an effective technical means for high-sensitivity and high-precision monitoring of organic pollutants in the external atmospheric environment.

[0113] Example 2: In-situ sampling and detection of gaseous volatile organic compounds and volatile organic compound particles during isoprene ozone oxidation.

[0114] Isoprene (a volatile liquid, insoluble in water but soluble in organic solvents such as ethanol and ether), a common bio-based VOC, reacts with ozone to form formaldehyde, methyl vinyl ketone, and methacrolein, as well as a large amount of secondary organic aerosols. The separation and detection of gaseous and particulate products using a dual-channel helical tube can help analyze the role of isoprene in particle formation and growth during the reaction, elucidating the transformation mechanism of bio-based VOCs and their environmental impact.

[0115] Before the experiment, ensure that the first absorption unit, second absorption unit, first detection component, second detection component, and two gas recovery devices are in normal working order and electrically connected to the two electrical controllers 14. Adjust the operating parameters of each unit in the dual-channel in-situ detection system to ensure the accuracy and repeatability of the experiment. Specifically, the electronic air flow meters 12 in both gas recovery devices are set to a flow rate of 0.3 L / min, the peristaltic pump in the liquid flow control device 7 is set to a flow rate of 0.3 mL / min, and the diversion valve 8 is set to collect one sample every 5 minutes.

[0116] Standard isoprene was precisely added to smoke chamber 1 to prepare an environmental simulation gas containing 100 ppb of the target organic compound. The oil-free vacuum pump 13 and peristaltic pump were activated to allow the environmental simulation gas to enter the first and second absorption units. Subsequently, 150 ppb of ozone was added to smoke chamber 1 via an ozone generator to ensure complete reaction of the isoprene. The spiral tube 3 effectively captured isoprene and gaseous and particulate products into the absorption liquid. After passing through the first and second absorption units, the sample vial 9 was fed into a gas chromatography-mass spectrometry (GC / MS) instrument via a liquid flow control device 7 for the separation and quantitative analysis of the target organic compound. By comparing the results of the experimental gas phase pathway (A pathway) and the gas-particulate phase pathway (B pathway), the feasibility and accuracy of the dual-channel in-situ detection system provided in this disclosure for the detection of gaseous and particulate volatile organic compounds were evaluated.

[0117] This experiment demonstrates the capability of the dual-channel in-situ detection system provided in this disclosure to perform in-situ sampling and precise analysis of isoprene ozone oxidation products in the atmosphere under laboratory conditions. This dual-channel in-situ detection system can effectively distinguish and capture gaseous and particulate organic matter, providing highly sensitive and accurate analytical results, thus offering important experimental methods and scientific evidence for air pollution monitoring and environmental research. By combining dual-channel in-situ sampling technology with the separation, absorption, control, and detection of gaseous and particulate volatile organic compounds, comprehensive analysis of products generated during the isoprene ozone oxidation process is achieved. This provides strong technical support for in-depth research into the sources and transformation mechanisms of secondary air pollutants.

[0118] Example 3: Real-time monitoring of gaseous volatile organic compounds and volatile organic compound particles in the ambient atmosphere

[0119] Install the dual-channel in-situ detection system provided in this disclosure in the external atmospheric environment where monitoring is required. Before the experiment, ensure that the first absorption unit, second absorption unit, first detection component, second detection component, and two gas recovery devices are in normal working order and electrically connected to the two electrical controllers 14. Adjust the operating parameters of each unit in the dual-channel in-situ detection system to ensure the accuracy and repeatability of the experiment. The electronic air flow meter 12 in the two gas recovery devices is set to a flow rate of 0.5 L / min, the peristaltic pump in the liquid flow control device 7 is set to a flow rate of 0.4 mL / min, and the diversion valve 8 is set to collect one sample every 5 minutes.

[0120] The first and second absorption units are exposed to the outside atmosphere, and volatile organic compounds in the outside atmosphere are captured by the dual-channel spiral tube 3 and absorbed into a pre-prepared absorption liquid. After a certain period of collection, the captured sample is sent to a liquid chromatography-electrostatic field orbital trap high-resolution mass spectrometer (Orbitrap–LC / MS) for detection via a liquid flow control device 7. During this process, the gas phase pathway (A pathway) and the gas-particle phase pathway (B pathway) can distinguish complex atmospheric chemical components, including secondary aerosols and high oxidation state substances (HOMs).

[0121] Example 3 demonstrates the ability of the dual-channel in-situ detection system provided in this disclosure to perform real-time monitoring of volatile organic compounds in a real atmospheric environment, thereby verifying its important application value and technical advantages in environmental monitoring and scientific research.

[0122] The in-situ collection and offline detection method for volatile organic compounds (VOCs) in the atmosphere provided in this disclosure has the following five advantages: 1. The in-situ collection method can effectively avoid pipeline losses during VOC sample introduction, reducing the uncertainty of sample detection at the source; 2. Using a spiral tube 3 to capture VOCs increases gas-liquid turbulence and contact area, while the absorbent can be flexibly adjusted based on the target substance, effectively improving absorption efficiency; 3. This method preserves real-time environmental samples, which can meet the requirements of various offline detection methods, such as high-performance liquid chromatography (HPLC) and gas chromatography. Mass spectrometry (GC / MS) and high-resolution liquid chromatography-electrostatic field orbital trap mass spectrometry (Orbitrap–LC / MS) enable high-sensitivity, high-resolution analysis of compounds in complex environmental samples, thereby revealing details of atmospheric chemical transformation processes; fourth, the differentiation between gaseous and particulate phase samples during sample collection allows for the detection of secondary aerosols and highly oxidized substances, providing a more comprehensive understanding of the transformation and influence mechanisms of atmospheric volatile organic compounds; fifth, the dual-channel in-situ detection system is stable and easy to operate, fully meeting the observation needs of various locations.

[0123] Those skilled in the art will understand that the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways, even if such combinations or combinations are not explicitly described in this disclosure. In particular, the features described in the various embodiments and / or claims of this disclosure can be combined and / or combined in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or combinations fall within the scope of this disclosure.

[0124] It should also be noted that the directional terms mentioned in the embodiments, such as "up," "down," "front," "back," "left," and "right," are only for reference to the directions in the accompanying drawings and are not intended to limit the scope of protection of this disclosure. Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or constructions will be omitted where they may cause confusion in understanding this disclosure, and the shapes and dimensions of the components in the drawings do not reflect actual size and proportion, but are only schematic representations of the embodiments of this disclosure.

[0125] Unless otherwise stated, the numerical parameters in this specification and the appended claims are approximate values ​​and can be varied according to desired characteristics derived from the content of this disclosure. Specifically, all figures used in the specification and claims to indicate composition, reaction conditions, etc., should be understood to be modified by the term "about" in all cases. Generally, this means that a specific amount may vary by ±10% in some embodiments, ±5% in some embodiments, ±1% in some embodiments, and ±0.5% in some embodiments.

[0126] The use of ordinal numbers such as "first," "second," "third," etc., in the specification and claims to modify the corresponding elements does not imply that the element has any ordinal number, nor does it represent the order of one element with another element, or the order of manufacturing methods. The use of these ordinal numbers is only to enable a named element to be clearly distinguished from another element with the same name.

[0127] Furthermore, unless specifically described or required to occur in a specific order, the order of the above steps is not limited to those listed above and can be varied or rearranged according to the desired design. Moreover, the above embodiments can be used in combination with each other or with other embodiments based on design and reliability considerations; that is, technical features from different embodiments can be freely combined to form more embodiments.

[0128] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A dual-channel in-situ detection system, characterized in that, include: smoke box; The first absorption unit is disposed inside the smoke box and is configured to absorb gaseous volatile organic compounds from the outside atmosphere using a first absorption liquid circulating inside the first absorption unit to obtain a first sample to be tested. The first detection component is connected to multiple liquid outlets of the first absorption unit and is configured to receive and detect the first sample to be tested. The second absorption unit, located inside the smoke chamber, is configured to absorb gaseous volatile organic compounds and volatile organic compound particles from the external atmosphere using a second absorption liquid circulating within the second absorption unit, thereby obtaining a second sample to be tested. The second detection component, connected to multiple outlets of the second absorption unit, is configured to receive and detect the second sample to be tested.

2. The dual-channel in-situ detection system according to claim 1, characterized in that, Both the first absorption unit and the second absorption unit include: case; Two spiral tubes connected in sequence are disposed within the housing. The air inlet of each spiral tube is configured to receive at least one of the gaseous volatile organic compounds and the volatile organic compound particles. The liquid inlet of each spiral tube is configured to receive either the first absorbent or the second absorbent, such that the first absorbent or the second absorbent absorbs at least one of the gaseous volatile organic compounds and the volatile organic compound particles within the spiral tube. The liquid outlet of each spiral tube is configured to discharge either the first test sample or the second test sample.

3. The dual-channel in-situ detection system according to claim 2, characterized in that, Both the first absorption unit and the second absorption unit further include: An absorbent supply mechanism is provided, wherein the outlet of the absorbent supply mechanism is connected to the inlet of the spiral tube, and the absorbent supply mechanism is configured to supply the first absorbent or the second absorbent into the spiral tube.

4. The dual-channel in-situ detection system according to claim 3, characterized in that, A accommodating space exists between the housing and the two spiral tubes, and both the first absorption unit and the second absorption unit further include: A circulating water supply mechanism, connected to the housing, is configured to supply ultrapure water to the accommodating space to insulate the spiral tube, enabling the spiral tube to adapt to different ambient temperatures.

5. The dual-channel in-situ detection system according to claim 2, characterized in that, The first absorption unit further includes: A filtration device, one end of which is connected to the outside atmosphere and the other end of which is connected to the air inlet of the spiral tube, is provided with a fiber membrane, which is suitable for collecting volatile organic compound particles from the outside atmosphere on the fiber membrane by means of filtration and adsorption, so that the gaseous volatile organic compounds enter the spiral tube.

6. The dual-channel in-situ detection system according to claim 2, characterized in that, Both the first detection component and the second detection component include: A liquid flow control device, wherein the inlet of the liquid flow control device is connected to the outlet of the spiral tube, and is configured to adjust the flow rate of the first test sample or the second test sample.

7. The dual-channel in-situ detection system according to claim 6, characterized in that, Both the first detection component and the second detection component further include: The separation component, connected to the outlet of the liquid flow control device, is configured to split the first test sample or the second test sample in chronological order and collect them separately.

8. The dual-channel in-situ detection system according to claim 7, characterized in that, Both the first detection component and the second detection component further include a detection device, which is any one of the following: gas chromatography-mass spectrometry, liquid chromatography, and liquid chromatography-electrostatic track trap high-resolution mass spectrometry.

9. The dual-channel in-situ detection system according to claim 6, characterized in that, Also includes: Two gas recovery devices are connected to the gas outlets of the spiral tubes belonging to the first absorption unit and the second absorption unit, respectively, and are configured to pump the outside air that has been absorbed by the first absorption liquid and the second absorption liquid back into the external environment.

10. The dual-channel in-situ detection system according to claim 9, characterized in that, The ratio of the velocity of the outside atmosphere after absorption by the first absorbent liquid to the velocity of the first sample to be tested is 1, and the ratio of the velocity of the outside atmosphere after absorption by the second absorbent liquid to the velocity of the second sample to be tested is 1.

Images