A sampling system for semi-volatile organic compounds in ambient air and exhaust gas

Abstract

The present invention discloses a sampling system for semi-volatile organic compounds in ambient air and exhaust gas, which belongs to the field of environmental monitoring technology, and includes an automatic sampling module and a sampling efficiency investigation module; the automatic sampling module includes an automatic sampling base and a sampling cavity, the automatic sampling base includes a waiting area, a sampling area and a sample storage area, and a plurality of the sampling cavities are arranged in the waiting area, the sampling area and the sample storage area respectively, the sampling cavity in the waiting area and the sampling cavity in the sample storage area are both provided with sealing covers at the top, and the sampling cavity in the sampling area is provided with a sampling cover and a sampling assembly at the top; the sampling cover is connected to the sampling efficiency investigation module; the sampling area and the sample storage area are both provided with a temperature regulating module. The present invention can improve the degree of sampling automation and the efficiency of detection and analysis; at the same time, it can add substitutes in the sampling process through the sampling efficiency investigation module to characterize the loss or recovery rate of the entire pre-treatment process and judge the sampling accuracy.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental monitoring, and in particular relates to a sampling system for semi-volatile organic matter in ambient air and waste gas. Background Art

[0002] Semi-volatile organic pollutants (SVOCs) usually refer to organic substances with boiling points between 170 and 350°C and low vapor pressure. Many SVOCs are directly harmful to the ecological environment or human health. Specific examples include dioxins, polycyclic aromatic hydrocarbons, organic pesticides, etc. They exist in the ambient air in the form of gas, aerosol, or attached to particulate matter. Therefore, it is necessary to monitor SVOCs in ambient air and exhaust gas.

[0003] The existing detection of semi-volatile organic compounds in ambient air and exhaust gas needs to be carried out according to the steps of sampling, extraction, enrichment, concentration and volume determination, and analysis, among which the sampling process as the first step is particularly critical. Since the concentrations of many SVOCs in the atmosphere are at trace levels, it is necessary to add an enrichment step before the analysis and testing. For organic matter in different forms, the pretreatment methods used are also different. Therefore, a large number of samples need to be collected for subsequent analysis. The existing detection and analysis system only has a sampling device for a single sample, and the number of samples collected is limited. Large-scale and long-term monitoring requires sampling personnel to go to the sampling site to replace consumables and accessories when changing samples, which is time-consuming, labor-intensive, and inconvenient. It is easy to have a long time interval between sample sampling and cannot adapt to continuous rapid automatic sampling and analysis.

[0004] At the same time, in the existing SVOCs monitoring methods, substitutes are only added during the sample extraction stage to evaluate the recovery rate starting from the extraction step; however, the recovery rate of the target object in the sampling process cannot be accurately judged, which may cause the monitoring results to be low. Summary of the invention

[0005] The object of the present invention is to provide a sampling system for semi-volatile organic compounds in ambient air and exhaust gas to solve the problems existing in the background technology.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A sampling system for semi-volatile organic compounds in ambient air and exhaust gas, comprising an automatic sampling module and a sampling efficiency inspection module;

[0008] The automatic sampling module comprises an automatic sampling base and a sampling cavity, the automatic sampling base comprises a waiting area, a sampling area and a sample storage area, a plurality of the sampling cavities are respectively arranged in the waiting area, the sampling area and the sample storage area, the sampling cavity in the waiting area and the sampling cavity in the sample storage area are both provided with sealing covers on the top, and the sampling cavity in the sampling area is provided with a sampling cover and a sampling assembly on the top; the sampling cover is connected to the sampling efficiency inspection module, and the sampling area and the sample storage area are both provided with a temperature adjustment module;

[0009] The sampling cavity has an inverted cone-shaped cavity structure, and is provided with a filter membrane pressure ring, a filter membrane, a first support member, a solid-phase adsorption material, and a second support member in sequence from top to bottom. An outlet channel is provided on one side of the top opening of the sampling cavity, and the outlet channel is connected to the bottom of the sampling cavity.

[0010] Furthermore, the sampling cover and the sealing cover are connected to the corresponding sampling cavity through sealing nuts respectively. A sampling inlet and a sampling outlet are provided on the top of the sampling cover. The sampling inlet is located at the center of the sampling cover and is connected to the corresponding sampling cavity, and the sampling outlet is connected to the outlet channel of the corresponding sampling cavity.

[0011] Furthermore, the sampling component includes an oil-free air pump, a flow controller, a three-way switching valve and a filter. The two groups of the oil-free air pump and the flow controller are respectively connected to the three-way switching valve, one end of the three-way switching valve is connected to the sampling outlet, and the filter is located on the pipeline between the three-way switching valve and the sampling outlet.

[0012] Furthermore, the sampling efficiency investigation module includes a six-way switching valve, an inert gas input assembly, a substitute solution bottle and a quantitative ring, the inert gas input assembly, the substitute solution bottle and the quantitative ring are respectively connected to the six-way switching valve, the two ends of the quantitative ring are respectively connected to the two ports of the six-way switching valve, one end of the substitute solution bottle is connected to the inert gas source through a pressure reducing valve, a through hole is provided on the top of the sampling cover, and the six-way switching valve is connected to the sampling cavity of the sampling area through the through hole.

[0013] Furthermore, the gas source of the inert gas input component is nitrogen, and the inert gas input component is provided with a nitrogen pressure reducing valve, an electromagnetic switch valve and a flow limiting valve in sequence from the gas source to the six-way switching valve.

[0014] Furthermore, one port of the six-way switching valve is connected to a waste liquid barrel.

[0015] Furthermore, a boss is provided at the bottom of the sampling cavity, and a groove matching with the boss is correspondingly provided on the automatic sampling base, and the sampling cavity and the automatic sampling base are fixed by plugging the boss and the groove.

[0016] Furthermore, the temperature regulating module adopts semiconductor refrigeration, and a heat insulation plate is provided between the sampling area and the sample storage area.

[0017] The beneficial effects of the present invention are:

[0018] 1) Improve sampling automation. The automatic sampling module is divided into three areas. When the sample is temporarily stored in the storage area, the waiting area transfers the new sampling cavity to the sampling area to maintain the sampling operation, increase the number of samples collected, improve the sampling efficiency, and ensure that the sampling interval time is controllable.

[0019] 2) Sampling process substitutes are added during sampling. Different from the substitutes added during the extraction process, the sampling efficiency investigation module can be used to add substitutes during the sampling process to characterize the loss or recovery rate of the entire monitoring process and judge the accuracy of the results.

[0020] 3) The sampling cavity in the sample storage area can be directly connected to the back-end enrichment analysis instrument to complete the subsequent processing steps on site; at the same time, the sampling cavity in the sample storage area can also be transported to the laboratory sample machine to complete the subsequent analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram of a sampling system of the present invention;

[0022] Figure 2 This is a schematic diagram of the installation of the sampling cavity in the sampling area of ​​the present invention;

[0023] Figure 3 Schematic diagram of the automatic injection base in the present invention;

[0024] Figure 4 This is a schematic diagram of the quantitative process of the substitute solution in the sampling efficiency investigation module of the present invention, in which the dotted line represents the working flow path;

[0025] Figure 5 This is a schematic diagram of adding a substitute solution in the sampling efficiency investigation module of the present invention, wherein the dotted line in the figure represents the working flow path;

[0026] In the figure, 1-automatic injection module, 101-waiting area, 102-sampling area, 103-sample storage area, 11-automatic injection base, 12-sampling chamber, 121-sealing nut, 122-solid phase adsorption material, 123-export channel, 124-boss, 125-groove, 126-filter membrane, 127-first support member, 128-second support member, 129-insulation board, 13-sampling cover, 131-sampling inlet, 132-sampling outlet , 133-through hole, 14-sealing cover, 15-oil-free vacuum pump, 16-flow controller, 17-three-way switching valve, 18-filter, 19-temperature adjustment module, 2-sampling efficiency investigation module, 21-six-way switching valve, 22-inert gas input assembly, 221-nitrogen pressure reducing valve, 222-electromagnetic switch valve, 223-flow limiting valve, 23-substitute solution bottle, 24-quantitative ring, 25-pressure reducing valve, 26-electromagnetic valve, 3-waste liquid barrel. DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0028] See also Figure 1-Figure 5 , the present invention provides a technical solution:

[0029] A sampling system for semi-volatile organic compounds in ambient air and exhaust gas, comprising an automatic sampling module 1 and a sampling efficiency inspection module 2;

[0030] The automatic sampling module 1 includes an automatic sampling base 11 and a sampling cavity 12. The automatic sampling base 11 includes a waiting area 101, a sampling area 102 and a sample storage area 103. The plurality of sampling cavities 12 are respectively arranged in the waiting area 101, the sampling area 102 and the sample storage area 103. The sampling cavity 12 of the waiting area 101 and the sampling cavity of the sample storage area are both provided with a sealing cover 14 at the top. The sampling cavity 12 of the sampling area 102 is provided with a sampling cover 13 and a sampling assembly at the top. The sampling cover 13 is connected to the sampling efficiency inspection module 2. The sampling area 102 and the sample storage area 103 are both provided with a temperature adjustment module 19.

[0031] The sampling chamber 12 has an inverted cone-shaped cavity structure, and is provided with a filter membrane pressure ring, a filter membrane 126, a first support member 127, a solid-phase adsorption material 122 and a second support member 128 from top to bottom. An outlet channel 123 is provided on one side of the top opening of the sampling chamber 12, and the outlet channel 123 is connected to the bottom of the sampling chamber 12.

[0032] like Figure 1 As shown, through the above technical solution, the automatic sampling base 11 is divided into three working areas, namely the waiting area 101, the sampling area 102 and the sample storage area 103, and each working area is provided with a sampling cavity 12.

[0033] For the waiting area 101, the sampling chamber 12 here is placed at the corresponding position of the automatic sampling base 11 after the internal arrangement, and the top of the sampling chamber 12 is sealed by a sealing cover to prevent external pollutants from entering the sampling chamber 12 and affecting subsequent sampling results.

[0034] Specific as Figure 2 As shown, the inverted conical cavity of the sampling cavity 12 is provided with a filter membrane pressure ring, a filter membrane 126, a first support member 127, a solid phase adsorption material 122 and a second support member 128 in sequence from top to bottom.

[0035] The sampling chamber 12 has an inverted cone-shaped cavity structure, so that after the gas enters, it diffuses around the filter membrane 126 (surrounded by air, low damping) under the action of the filter membrane 126 and the like (damping), and enters the solid phase adsorption material 122 area through the filter membrane 126 in a relatively uniform distribution; at the same time, through the inverted cone structure, there is basically no "dead area" or invalid area where the sample gas does not flow through, and the solid phase adsorption material 122 in each area can contact with the sample gas and take effect; at the same time, the inverted cone structure also ensures the adsorption effect, so that the total internal volume is larger, and the length of the cavity will not be too long, thereby reducing the space occupied by the sampling system.

[0036] At the same time Figure 2 As shown, the outlet channel 123 is connected to the flow path at the bottom of the sampling chamber 12, has a small caliber and a small dead volume, and the dead volume accounts for no more than 1% of the total volume in the chamber, and has no obvious effect on subsequent enrichment and extraction processes, and there is no need to consider residues.

[0037] The filter ring in the sampling cavity 12 is used to press the filter 126 onto the sampling cavity 12 to fix it to the sampling cavity 12. The filter 126 is generally 0.22μm or 0.45μm, and the filter 126 is made of polytetrafluoroethylene or quartz. The filter 126 collects particulate matter in the air and also collects SVOCs adsorbed on the particles; generally, water is not expected to enter the subsequent enrichment step, so the water in the sample needs to be removed as much as possible. Therefore, when the water content in the sample is high, the filter 126 is preferably a polytetrafluoroethylene filter 126, which uses its hydrophobicity to make it difficult for liquid water to pass through.

[0038] The first support member 127 and the second support member 128 are used to support the filter membrane 126 and the solid phase adsorption material 122, and can be made of a stainless steel mesh or a metal sintered block, which can ensure that the sample can pass smoothly while supporting the interior;

[0039] The solid phase adsorption material 122 is accumulated between the first support member 127 and the second support member 128. The filter membrane 126 and the solid phase adsorption material 122 are connected in series for collection. The solid phase adsorption material 122 is located at the rear end of the filter membrane 126. The SVOCs on the particulate matter are collected through the filter membrane 126, and the gaseous SVOCs are collected through the solid phase adsorption material 122. Preferably, the volume of the solid phase adsorption material pile for the ambient air sample should not be less than 350 mL, and the volume of the solid phase adsorption material pile for the exhaust gas sample should not be less than 30 mL; preferably, the solid phase adsorption material adopts an adsorption material resistant to organic solvents, which can be a single filler or a mixed filler. The adsorption material can be selected from quartz glass porous microbeads, polyurethane foam (PUF), macroporous resin, etc. If it is a granular adsorption material, the size is generally 20~40 mesh.

[0040] When the sample humidity is particularly high or the total collected volume is particularly large, causing the total amount of water entering the solid phase adsorption material area to be non-negligible (difficult to remove even by relying on the polytetrafluoroethylene filter membrane 126), a small amount of dehydrating agent may be added to the bottom of the solid phase adsorption material. Preferably, the dehydrating agent is anhydrous sodium sulfate, and the water can be further removed by the dehydrating agent.

[0041] For the sampling area 102, the sampling cavity 12 of the waiting area 101 enters the sampling area 102 through the automatic sampling base 11. The automatic sampling base 11 is provided with a horizontally movable work surface, which can drive the sampling cavity 12 to move horizontally into different working areas. The automatic sampling device technology is mature and will not be described in detail.

[0042] like Figure 1 and Figure 2 As shown, a sampling cover 13 is provided above the sampling chamber 12 of the sampling area 102, and the connection is fixed by a sealing nut 121. It can be known that a sealing ring is provided at the connection between the sampling cover 13 and the sampling chamber 12 to ensure air tightness. At the same time, since a sampling inlet 131 and a sampling outlet 132 are provided at the top of the sampling cover 13, the sampling inlet 131 is connected to the sampling chamber 12, and the sampling is connected to the outside world through the sampling inlet 131; the sampling outlet 132 corresponds to and is connected to the outlet channel 123, and the excess exhaust gas in the sampling chamber 12 can be discharged through the sampling outlet 132.

[0043] Specifically, the sampling inlet 131 is connected to the external main sampling pipe and communicated with the local atmosphere. Since the two groups of oil-free air pumps 15 and flow controllers 16 are respectively connected to the three-way switching valve 17, a group of oil-free air pumps 15 and flow controllers 16 are started at this time (the two groups of oil-free air pumps 15 and flow controllers 16 are used alternately to extend the life of the electrical appliances), and the ambient air is collected at a constant flow rate. Preferably, the maximum gas collection flow rate is 100L / min, and the longest gas collection time is 24h. If the waste gas from a fixed pollution source is collected, the sampling inlet 131 is connected to the waste gas sampling pipe, and the sampling flow rate and time are reduced accordingly, such as the gas collection flow rate is 0.5L / min, and the gas collection time is set to 1h. Further, a filter 18 is set between the three-way switching valve 17 and the sampling outlet 132, and the filter 18 can effectively filter fine particles and impurities to protect the three-way switching valve 17, the flow controller 16 and the oil-free air pump 15.

[0044] Furthermore, SVOCs include benzo[a]pyrene, which is a controlled substance in the Ambient Air Quality Standard GB3095-2012. During the collection of ambient air, benzo[a]pyrene requires a 24-hour average value, and ambient air needs to be collected for 24 hours. The sampling inlet is equipped with a flow controller, and the sampling system can automatically adjust the flow rate of gas collection, and reduce the flow rate of gas collection according to the required sampling time and sampling volume, thereby reducing the load and power consumption. If it is continuous collection, after a group of flow controllers and pumps work continuously for 24 hours, another group can collect subsequent samples, thereby alternating work and extending the life of the electrical appliances; at the same time, during the exhaust gas collection, the sampling system can be adjusted according to demand for interval collection or continuous collection to improve the degree of automation.

[0045] The size of the sampling inlet 131 is only for illustration. The diameter of the sampling inlet of the present embodiment is 2 cm, and the diameter of the inlet can be increased according to the actual sampling process. At the same time, the inlet and outlet channels of the sampling cavity are both located on one side above, so that the sampling inlet 131 and the sampling outlet 132 are both arranged on the top of the sampling cover 13, which is convenient for realizing the automatic placement of the sampling cover 13 or the sealing cover 14, and the sampling cover 13 can be transferred and sampled as a whole after being connected to the sampling cavity 12. When the sampling cavity 12 of the sample storage area 103 is sealed, the sealing can be completed by adding the sealing cover 14 on the top, which improves the sealing efficiency and reduces the cost. Moreover, the clogging of the extraction instrument caused by the falling of particle fragments during the sampling is basically not considered.

[0046] At the same time, when the sampling cavity 12 of the sampling area 102 is sampling, the temperature regulating module 19 outside the sampling area 102 is in a cooling state. It can be known that if the temperature and humidity of the gas sample are high, the supersaturated water will condense into liquid due to the temperature drop after entering the sampling cavity 12, and the filter membrane 126 made of polytetrafluoroethylene will block most of the condensed water from entering the area behind the sampling cavity 12; the gas sample passing through the filter membrane 126, the gaseous and aerosol semi-volatile organic compounds (SVOCs), are adsorbed by the solid phase adsorption material 122. Controlling the sampling cavity 12 at a relatively low temperature above 0°C will not cause ice to form due to too low a temperature, and will also improve the adsorption efficiency of the solid phase adsorption material 122, and even adsorb volatile organic compounds (VOCs) with relatively high boiling points, thereby expanding the range of collected substances. Preferably, the temperature of the sampling cavity 12 in the sampling area is controlled at 5±2°C to improve the adsorption rate of SVOCs.

[0047] At the same time, when the sampling cavity 12 of the sampling area 102 performs sampling, the sampling efficiency inspection module 2 operates synchronously. Figure 1 As shown, the six-way switching valve 21 is connected to the through hole 133 of the sampling cover 13 through a pipeline.

[0048] The working process of sampling efficiency inspection module 2 is as follows Figure 4 and Figure 5 As shown:

[0049] like Figure 4 As shown, the six-way switching valve 21 is switched to connect the substitute solution bottle 23 and the quantitative ring 24. Since one end of the substitute solution bottle 23 is connected to the inert gas source through the pressure reducing valve 25, the inert gas source uses nitrogen. At the same time, there is a pressure reducing valve between the substitute solution bottle 23 and the inert gas source, so that the air pressure in the substitute solution bottle is slightly greater than the atmospheric pressure. Figure 4 In the embodiment, there is a solenoid valve 26 between the six-way switching valve 21 and the waste liquid barrel 3. When the solenoid valve 26 is opened, the pressure in the substitute solution bottle 23 is slightly greater than the atmospheric pressure, so that the substitute solution in the substitute solution bottle 23 flows into the quantitative ring 24 under the action of the pressure difference and fully replaces the material inside the quantitative ring 24. After the replacement is sufficient, the solenoid valve 26 is closed.

[0050] like Figure 5 As shown, the six-way switching valve 21 is switched, and the inert gas input assembly 22 is started. The inert gas source of the inert gas input assembly 22 is nitrogen. The inert gas input assembly 22 is provided with a nitrogen pressure reducing valve 221, an electromagnetic switch valve 222 and a flow limiting valve 223 in sequence from the gas source to the six-way switching valve 21. The electromagnetic switch valve 222 is opened, and the nitrogen is controlled by the flow limiting valve 223 to fill the substitute solution in the quantitative ring 24 into the sampling chamber 12 at about 20 mL / min (fixed flow rate). After ensuring that the substitute solution in the quantitative ring 24 is fully filled, the electromagnetic switch valve 222 and the six-way switching valve 21 are closed.

[0051] Since the sampling process substitute is added during sampling, which is different from the addition of substitutes during the extraction process, the sampling efficiency inspection module 2 can be used to add substitutes during the sampling process to characterize the loss or recovery rate of the entire monitoring process and judge the accuracy of the results. At the same time, substitutes can be added multiple times at equal time intervals during the sampling process, and repeated Figure 4~Figure 5 If repeated addition is required, the concentration of the substitute solution should be prepared to be 1 / n of that added once (n is the number of additions).

[0052] For the sample storage area 103, after the sampling cavity 12 of the sampling area 102 is collected and the substitute is added, it enters the sample storage area 103 through the automatic sampling base 11. At this time, the sampling cavity 12 in the sample storage area 103 removes the sampling cover 13 and replaces the upper sealing cover 14.

[0053] like Figure 1 As shown, a sealing cover 14 is provided on the top of the sampling cavity of the sample storage area 103. After the sampling of the sampling cavity 12 of the sampling area 102 is completed, the automatic sampling base 11 enters the sample storage area 103. At this time, the sampling cavity 12 of the sample storage area 103 can be directly connected to the back-end processing monitoring system to complete subsequent enrichment, analysis and other steps on site; at the same time, the sampling cavity 12 of the sample storage area 103 can also be taken away by people and transported to the laboratory to complete subsequent analysis, which is convenient for taking and realizing independent sample loading. At the same time, the sampling cover and the sealing cover can be automatically assembled with the sampling cavity to improve the degree of automation. The specific covering method can use the automatic covering machine in the prior art.

[0054] Since the automatic sampling module 1 is divided into three working areas, when the sample storage area 103 is extracting, the waiting area 101 transfers a new sampling cavity 12 to the sampling area 102 to maintain the sampling operation, thereby increasing the number of sample collections, improving the sampling work efficiency, and ensuring that the sampling interval time is controllable.

[0055] For the sampling chamber 12 of the sample storage area 103, the temperature regulating module 19 of the sample storage area 103 controls the temperature to be below 10°C. By controlling the temperature of the sample storage area 103 to maintain a low temperature, because the boiling point of SVOCs is relatively high, when they are adsorbed on the adsorbent and the temperature is below 10°C, the storage time of the sampling chamber of the sample storage area 103 can be greatly increased, and the loss during the storage process can be reduced. In this case, not only the unattended working time is increased, but also if the sampling chamber needs to be transported to the laboratory for analysis by personnel, the time interval for personnel to arrive can be extended, reducing manpower.

[0056] like Figure 3As shown, a boss 124 is provided at the bottom of the sampling cavity 12 , and the automatic sampling base 11 is correspondingly provided with a groove 125 matched with the boss 124 . The sampling cavity 12 and the automatic sampling base 11 are plugged and fixed via the boss 124 and the groove 125 .

[0057] Meanwhile, the temperature adjustment module 19 can be specifically disposed in the automatic sampling base 11 , and the upper sampling cavity 12 can be cooled by the semiconductor refrigeration component in the automatic sampling base 11 .

[0058] The principle of semiconductor refrigeration is: using the thermoelectric effect of semiconductors to produce cold energy, connecting two different metals with a conductor, and connecting direct current, the temperature at one connection point decreases, and the temperature at the other connection point increases. The cavity of the sampling chamber 12 and the automatic sampling base 11 adopt a metal structure, and the contact area between the bottom surface of the sampling chamber 12 and the automatic sampling base 11 is large. The semiconductor chip can be installed on the automatic sampling base 11, which is convenient for refrigeration. Furthermore, the refrigeration method of the temperature adjustment module 19 can also be considered to use compressor refrigeration.

[0059] Furthermore, a heat insulation board 129 is provided between the sampling area 102 and the sample storage area 103 to prevent the temperature disturbance in the sampling area 102 and the sample storage area 103 from affecting their respective work. The heat insulation board 129 in this embodiment separates the adjacent areas and encloses relatively independent closed areas. In addition to separating areas with different temperatures, the heat insulation board 129 in this embodiment can also prevent moisture in the external air from condensing into water droplets or water mist on the outer surface of the sampling cavity 12.

[0060] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not depart from the spirit and scope of the present invention, and should be within the scope of protection of the claims attached to the present invention.

Claims

1. A sampling system for semi-volatile organic compounds in ambient air and exhaust gas, characterized in that: It includes an automatic sampling module (1) and a sampling efficiency inspection module (2); The automatic sampling module (1) comprises an automatic sampling base (11) and a sampling cavity (12); the automatic sampling base (11) comprises a waiting area (101), a sampling area (102) and a sample storage area (103); a plurality of the sampling cavities (12) are respectively arranged in the waiting area (101), the sampling area (102) and the sample storage area (103); the tops of the sampling cavities (12) in the waiting area (101) and the sampling cavities (12) in the sample storage area (103) are both provided with sealing covers (14); the tops of the sampling cavities (12) in the sampling area (102) are provided with sampling covers (13) and sampling components; the sampling covers (13) are connected to the sampling efficiency investigation module (2); the sampling areas (102) and the sample storage areas (103) are both provided with temperature adjustment modules (19); The sampling cavity (12) has an inverted cone-shaped cavity structure, and the sampling cavity (12) is provided with a filter membrane pressure ring, a filter membrane (126), a first support member (127), a solid-phase adsorption material (122), and a second support member (128) in order from top to bottom. An outlet channel (123) is provided on one side of the top opening of the sampling cavity (12), and the outlet channel (123) is communicated with the bottom of the sampling cavity (12); The sampling efficiency investigation module (2) comprises a six-way switching valve (21), an inert gas input assembly (22), a substitute solution bottle (23) and a quantitative ring (24); the inert gas input assembly (22), the substitute solution bottle (23) and the quantitative ring (24) are respectively connected to the six-way switching valve (21); two ends of the quantitative ring (24) are respectively connected to two ports of the six-way switching valve (21); one end of the substitute solution bottle (23) is connected to an inert gas source via a pressure reducing valve (25); a through hole (133) is provided on the top of the sampling cover (13); and the six-way switching valve (21) is connected to the sampling cavity (12) of the sampling area (102) via the through hole (133); The sampling cover (13) is connected to the corresponding sampling cavity (12) via a sealing nut (121); a sampling inlet (131) and a sampling outlet (132) are provided at the top of the sampling cover (13); the sampling inlet (131) is located at the center of the sampling cover (13) and is in communication with the corresponding sampling cavity (12); the sampling outlet (132) is in communication with an outlet channel (123) of the corresponding sampling cavity (12); and the sampling assembly is connected to the sampling outlet (132).

2. The sampling system for semi-volatile organic compounds in ambient air and exhaust gas according to claim 1, characterized in that: The sampling assembly comprises an oil-free air pump (15), a flow controller (16), a three-way switching valve (17) and a filter (18); two groups of the oil-free air pump (15) and the flow controller (16) are respectively connected to the three-way switching valve (17); one end of the three-way switching valve (17) is connected to the sampling outlet (132); and the filter (18) is located on a pipeline between the three-way switching valve (17) and the sampling outlet (132).

3. The sampling system for semi-volatile organic compounds in ambient air and exhaust gas according to claim 1, characterized in that: The gas source of the inert gas input component (22) is nitrogen, and the inert gas input component (22) is provided with a nitrogen pressure reducing valve (221), an electromagnetic switch valve (222) and a flow limiting valve (223) in sequence from the gas source to the six-way switching valve (21).

4. The sampling system for semi-volatile organic compounds in ambient air and exhaust gas according to claim 1, characterized in that: One port of the six-way switching valve (21) is connected to the waste liquid barrel (3), and a solenoid valve (26) is provided between the six-way switching valve (21) and the waste liquid barrel (3).

5. The sampling system for semi-volatile organic compounds in ambient air and exhaust gas according to claim 1, characterized in that: The bottom of the sampling cavity (12) is provided with a boss (124), and the automatic sampling base (11) is correspondingly provided with a groove (125) that matches the boss (124), and the sampling cavity (12) and the automatic sampling base (11) are plugged and fixed via the boss (124) and the groove (125).

6. The sampling system for semi-volatile organic compounds in ambient air and exhaust gas according to claim 1, characterized in that: The temperature adjustment module (19) adopts semiconductor refrigeration, and a heat insulation board (129) is provided between the sampling area (102) and the sample storage area (103).

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