Air sampling pipe for working place

Abstract

The utility model relates to the technical field of air sampling tubes, and discloses an air sampling tube for a workplace, the air sampling tube for the workplace comprises a sealing cap, a filter material upper cover, a support pad and a filter material lower cover, the lower end of the sealing cap is fixedly provided with the filter material upper cover, and the lower side of the filter material upper cover is fixedly provided with a filter material pad. According to the air sampling tube for the workplace, the filter material sampling clamp provided with the filter material and the detachable front and rear cylindrical tubes filled with the solid adsorbent are connected in series and assembled into the sampling tube, the sampling tube can be used for simultaneously collecting toxic substances coexisting in a vapor state and an aerosol state in air, the filter material can be used for collecting nicotine in the aerosol state, and the sampling tube is simple in structure and convenient to use. In the actual sample pretreatment analysis process, the operation is very easy, an operator does not need to cut the solid adsorbent tube, the working efficiency is greatly improved, and the filter material sampling clamp and the solid adsorbent filling part can be recycled, so that the material use cost is greatly reduced.

Description

Technical Field

[0001] This utility model relates to the field of air sampling tube technology, specifically an air sampling tube for use in the workplace. Background Technology

[0002] The analytical methods for nicotine have been continuously developed. In addition to traditional chemical methods and titration methods, electrochemical methods, atomic absorption spectrometry, gas chromatography, spectrophotometry, and high-performance liquid chromatography have all been used to analyze and determine nicotine. However, most of these methods are used to study the detection of nicotine in tobacco products and biological materials. The literature reports on the detection of nicotine in the air using high-performance liquid chromatography, gas chromatography, and gas chromatography-mass spectrometry. However, these methods are mostly used on a large scale in site monitoring or individual exposure monitoring of tobacco smoke in the environment. There are few studies on nicotine in workplace air.

[0003] A small portion of the nicotine produced when cigarettes burn exists in gaseous form in the smoke and can be directly inhaled into the lungs. Most of it adheres to tiny particles (aerosols) composed of tar, moisture, and other chemicals. Once inhaled, these particles rapidly allow nicotine to enter the bloodstream through the alveoli. Nicotine produced when e-cigarettes are heated exists primarily as aerosol particles, which are typically smaller than cigarette smoke. Currently, the main sampling methods for collecting toxic substances in the air that coexist in vapor and aerosol states include the impregnation method, the foam plastic method, and the tandem method. NIOSH 2514 uses the XAD-4 solid adsorbent tube for sampling, but this sampling tube can only collect gaseous nicotine and not aerosol nicotine. Currently, there is no suitable air sampler on the market specifically designed for nicotine that coexists in the air in vapor and aerosol states. Utility Model Content

[0004] (a) Technical problems to be solved

[0005] The purpose of this invention is to provide an air sampling tube for use in the workplace, in order to solve the problem mentioned in the background art that the sampling tube can only collect gaseous nicotine and cannot collect aerosol nicotine.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, this utility model provides the following technical solution: an air sampling tube for the workplace, comprising a sealing cap, a filter media top cover, a filter media pad, a support pad, a filter media bottom cover, elastic plastic, a first filter tube, a first foam plastic, a first front-end solid adsorbent, a first glass wool, a sealing ring, a metal ring, a second filter tube, a second foam plastic, a second front-end solid adsorbent, a second glass wool, and a connecting cap. The lower end of the sealing cap is fixedly provided with the filter media top cover, the lower side of the filter media top cover is fixedly provided with the filter media pad, the lower side of the filter media pad is fixedly provided with the support pad, the lower end of the filter media top cover is fixedly provided with the filter media bottom cover, the lower end of the filter media bottom cover is fixedly provided with elastic plastic, and the lower end of the filter media bottom cover is fixedly provided with the first filter tube.

[0008] Preferably, a foam plastic is fixedly disposed inside the filter tube, and a front solid adsorbent is fixedly disposed at the lower end of the foam plastic.

[0009] Preferably, a glass wool is fixedly provided at the lower end of the first solid adsorbent, and a sealing ring is fixedly provided at the lower end of the first filter tube.

[0010] Preferably, a metal ring is fixedly provided on the lower side of the sealing ring, and a filter tube two is fixedly provided at the lower end of the first filter tube.

[0011] Preferably, a second type of foam plastic is fixedly disposed inside the second filter tube, and a second type of front-end solid adsorbent is fixedly disposed at the lower end of the second type of foam plastic.

[0012] Preferably, glass wool is fixedly provided at the lower end of the second solid adsorbent in the front section, and a connecting cap is fixedly provided at the lower end of the second filter tube.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] 1. This workplace air sampling tube is assembled by connecting a filter media sampling clip with two detachable cylindrical sections filled with solid adsorbent in series. It can be used to simultaneously collect toxic substances coexisting in the air in vapor and aerosol states. The filter media can collect aerosol nicotine, and the sampling efficiency can reach 100% within the carrying capacity. The XAD-4 solid adsorbent can effectively adsorb vapor nicotine. The nicotine sampling tube can ensure that the sampling efficiency for nicotine can reach more than 90%. At the same time, the penetration capacity of the filled solid adsorbent for nicotine can meet the requirement of sampling for at least 2 hours at a concentration of 2 times the occupational exposure limit. The two cylindrical sections of the solid adsorbent filling part are detachable, which is very easy to operate in the actual sample pretreatment analysis process. The operator does not need to cut the solid adsorbent tube, which greatly improves the work efficiency. Moreover, both the filter media sampling clip and the solid adsorbent filling part are recyclable, which greatly reduces the material usage cost. For the treated filter media and solid adsorbent, methanol, a commonly used solvent, is used as the eluent / desorption solution. After vortexing, the eluent / desorption solution is separated by a chromatographic column and detected by liquid chromatography. This sampling tube can be used for any sampling method, such as fixed-point long / short-time sampling or individual long / short-time sampling. It can simultaneously sample and detect nicotine in both vapor and aerosol states in the air. Therefore, the development of nicotine sampling tubes has broad application prospects. Attached Figure Description

[0015] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0016] Figure 2 This is a schematic diagram of the split structure of the air sampling tube of this utility model;

[0017] Figure 3 This is a schematic diagram of the structure of the filter tube of this utility model;

[0018] Figure 4 This is a schematic diagram of the second structure of the filter tube of this utility model.

[0019] In the diagram: 1. Sealing cap; 2. Filter media top cover; 3. Filter media pad; 4. Support pad; 5. Filter media bottom cover; 6. Elastic plastic; 7. Filter tube one; 8. Foam plastic one; 9. Front-end solid adsorbent one; 10. Glass wool one; 11. Sealing ring; 12. Metal ring; 13. Filter tube two; 14. Foam plastic two; 15. Front-end solid adsorbent two; 16. Glass wool two; 17. Connecting cap. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] Please see Figure 1 - Figure 4 This utility model provides a technical solution: an air sampling tube for the workplace, which includes a sealing cap 1, a filter material top cover 2, a filter material pad 3, a support pad 4, a filter material bottom cover 5, an elastic plastic 6, a filter tube 7, a foam plastic 8, a front-end solid adsorbent 9, glass wool 10, a sealing ring 11, a metal ring 12, a second filter tube 13, a second foam plastic 14, a second front-end solid adsorbent 15, a second glass wool 16, and a connecting cap 17. The filter material top cover 2 is fixedly installed at the lower end of the sealing cap 1, the filter material pad 3 is fixedly installed at the lower side of the filter material top cover 2, the support pad 4 is fixedly installed at the lower side of the filter material pad 3, the filter material bottom cover 5 is fixedly installed at the lower end of the filter material top cover 2, the elastic plastic 6 is fixedly installed at the lower end of the filter material bottom cover 5, and the filter tube 7 is fixedly installed at the lower end of the filter material bottom cover 5.

[0022] Foam plastic 8 is fixedly installed inside the filter tube 7. A front solid adsorbent 9 is fixedly installed at the lower end of the foam plastic 8. Glass wool 10 is fixedly installed at the lower end of the front solid adsorbent 9. A sealing ring 11 is fixedly installed at the lower end of the filter tube 7.

[0023] A metal ring 12 is fixedly installed on the lower side of the sealing ring 11. A filter tube 13 is fixedly installed at the lower end of the filter tube 1 7. Foam plastic 14 is fixedly installed inside the filter tube 13. A front solid adsorbent 15 is fixedly installed at the lower end of the foam plastic 14. Glass wool 16 is fixedly installed at the lower end of the front solid adsorbent 15. A connecting cap 17 is fixedly installed at the lower end of the filter tube 13.

[0024] Working Principle: First, the solid adsorbent material is selected: This invention assembles a new type of air sampling tube by connecting filter media 3 (front end) and solid adsorbent (back end) in series. The front-end filter media 3 is mainly used to collect aerosol nicotine in the workplace air. The principle of filter media 3 in collecting aerosol substances is physical retention, which is non-selective. However, nicotine also exists in the workplace air in vapor form, so solid adsorbents are needed for selective adsorption. The front-end filter media 3 uses a glass fiber filter membrane. In order to improve the capture efficiency of vapor nicotine, a glass fiber filter membrane impregnated with 4% NaHSO4-5% glycerol solution is used as the front end. The impregnated glass fiber filter membrane can significantly improve the capture efficiency of vapor nicotine while retaining the ability to capture aerosol nicotine. The XAD-4 solid adsorbent is assembled at the back end, which can capture vaporized nicotine that permeates through the glass fiber filter membrane, further enhancing the adsorption of nicotine. It is particularly suitable for long-term sampling of low-concentration nicotine. The sampling tube's shape, material, and filling method are as follows: The nicotine sampling tube consists of a filter media 3 sampling clip and a solid adsorbent filling section. The filter media 3 sampling clip includes a 38mm long, 29mm outer diameter (25mm inner diameter) sampling clip and a 5mm long, 10mm outer diameter (8mm inner diameter) outlet end. The solid adsorbent filling section includes... The filter media consists of two detachable cylindrical tubes, front and rear. The front cylindrical tube includes a 30mm long, 13mm outer diameter (11mm inner diameter) solid adsorbent filling section and a 3mm long, 10mm outer diameter (8mm inner diameter) outlet end. The rear cylindrical tube includes a 20mm long, 13mm outer diameter (11mm inner diameter) solid adsorbent filling section and a 10mm long, 7mm outer diameter (4mm inner diameter) outlet end. The outlet end of the filter media 3 sampling clamp can be connected and sealed to the inlet end of the front cylindrical tube via a sealing ring 11. (Removable); the outlet end of the front cylindrical tube can be connected and sealed to the inlet end of the rear cylindrical tube via sealing ring 11 (also removable); the sampling tube can be made of materials such as polytetrafluoroethylene and polyethylene; the filter media 3 uses glass fiber filter paper; the solid adsorbent is XAD-4 solid adsorbent; the filling technique for the nicotine air sampling tube is as follows: first, place foam plastic or glass wool at the bottom of the rear cylindrical tube, then place 150-300 mg of XAD-4 solid adsorbent, then place foam plastic or glass wool again, and finally... Use elastic plastic 6 or metal ring 12 to compact and fix; connect the air outlet end of the front cylindrical tube to the air inlet end of the rear cylindrical tube through sealing ring 11 and seal and clamp it; put foam plastic or glass wool at the bottom of the front cylindrical tube, then put 300mg~600mg of XAD-4 solid adsorbent, then put foam plastic or glass wool, and finally compact and fix it with elastic plastic 6 or metal ring 12; ④ connect the air outlet end of the sampling clamp of the filter material 3, which has been installed with support pad and filter material 3, to the air inlet end of the front cylindrical tube through sealing ring 11 and seal and clamp it.⑤ Place sealing caps 1 (which can be sealed via bayonet or knob) on both ends of the sampling tube (the inlet end of the sampling clamp for filter media 3 and the outlet end of the cylindrical tube at the rear). The filled sampling tube should be tested for resistance. At a flow rate of 1.0 L / min, the air resistance should be less than 4.0 kPa. Type and treatment of filter media 3: Filter media 3 uses glass fiber membrane with a pore size not greater than 0.8 μm. Place the glass fiber membrane in a muffle furnace and bake at 450℃ for 2 hours. After baking, remove it and place it in a desiccator for later use. Weigh 4g of the membrane. Dissolve NaHSO4 and 5g glycerol in 100mL of pure water to prepare a 4% NaHSO4 + 5% glycerol solution. This solution is used as the impregnation solution for the filter membrane in the nicotine air sampling tube. Immerse the baked glass fiber filter membrane in the impregnation solution thoroughly for 1 hour, then remove it and place it in a desiccator until dry. If the indoor humidity is high, the soaked glass fiber filter membrane can be placed in an oven at 30℃ for 2 hours, then removed and stored in a desiccator. The eluent, elution method, and determination method for sample processing are as follows: Place filter material 3 and the first section of silica gel from the sampling tube into a sample bottle, and use 2.0mL of 1% ammonia-methanol as the desorption eluent; place the second section of silica gel into another sample bottle, and use 2.0mL of 1% ammonia-methanol as the eluent. Methanol-water was used as the desorption eluent. The mixture was vortexed for 30 min, filtered through a 0.22 μm organic phase syringe filter, and 5 μL of the eluent was injected. After separation on a C18 HPLC column, the sample was detected using a high-performance liquid chromatograph (HPLC) with a UV detector at 260 nm. The elution / desorption efficiency was 80.5%–101.0%, and the detection limit was 0.05 mg / L. The chromatographic conditions were: column temperature 35℃, mobile phase A (0.1% ammonia solution), and organic phase B (methanol), eluted at an A / B ratio of 40 / 60 isocratic. When the detection result exceeded the quantification range, it was diluted with 0.1% ammonia-methanol to the middle of the quantification range before further analysis.

[0025] Finally, it should be noted that the above content is only used to illustrate the technical solution of this utility model, and is not intended to limit the scope of protection of this utility model. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of this utility model do not depart from the essence and scope of the technical solution of this utility model.

Claims

1. An air sampling tube for use in the workplace, comprising a sealing cap (1), a filter media upper cover (2), a filter media pad (3), a support pad (4), a filter media lower cover (5), an elastic plastic (6), a first filter tube (7), a first foam plastic (8), a first front-end solid adsorbent (9), a first glass wool (10), a sealing ring (11), a metal ring (12), a second filter tube (13), a second foam plastic (14), a second front-end solid adsorbent (15), a second glass wool (16), and a connecting cap (17), characterized in that: A filter material top cover (2) is fixedly installed at the lower end of the sealing cap (1), a filter material pad (3) is fixedly installed on the lower side of the filter material top cover (2), a support pad (4) is fixedly installed on the lower side of the filter material pad (3), a filter material bottom cover (5) is fixedly installed at the lower end of the filter material top cover (2), an elastic plastic (6) is fixedly installed at the lower end of the filter material bottom cover (5), and a filter tube (7) is fixedly installed at the lower end of the filter material bottom cover (5).

2. An air sampling tube for the workplace according to claim 1, characterized in that: The filter tube (7) is fixedly provided with foam plastic (8), and the lower end of the foam plastic (8) is fixedly provided with front solid adsorbent (9).

3. An air sampling tube for the workplace according to claim 2, characterized in that: The lower end of the front solid adsorbent (9) is fixedly provided with glass wool (10), and the lower end of the filter tube (7) is fixedly provided with a sealing ring (11).

4. An air sampling tube for the workplace according to claim 3, characterized in that: A metal ring (12) is fixedly provided on the lower side of the sealing ring (11), and a filter tube (13) is fixedly provided at the lower end of the filter tube one (7).

5. An air sampling tube for the workplace according to claim 4, characterized in that: The filter tube 2 (13) is fixedly provided with foam plastic 2 (14), and the lower end of the foam plastic 2 (14) is fixedly provided with front solid adsorbent 2 (15).

6. An air sampling tube for the workplace according to claim 5, characterized in that: The lower end of the front solid adsorbent 2 (15) is fixedly provided with glass wool 2 (16), and the lower end of the filter tube 2 (13) is fixedly provided with a connecting cap (17).

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