CN212275513U

CN212275513U - Aerosol particle size spectrometer analysis device

Info

Publication number: CN212275513U
Application number: CN202020679451.3U
Authority: CN
Inventors: 张所容
Original assignee: Chongqing Feiyang Research Institute Of Measurement And Control Technology Co ltd
Current assignee: Chongqing Feiyang Research Institute Of Measurement And Control Technology Co ltd
Priority date: 2020-04-28
Filing date: 2020-04-28
Publication date: 2021-01-01
Anticipated expiration: 2030-04-28

Abstract

The invention relates to the technical field of aerosol analysis in atmospheric environment, in particular to an aerosol particle size spectrometer analysis device, which comprises a sample injection system and a gas circuit system, wherein the sample injection system comprises a sample injection pipe and a shell flow pipe; the middle part of the shell flow tube is provided with a sealing plug, and the sample inlet tube passes through the sealing plug; the height of the shell flow pipe is higher than that of the sample inlet pipe; the air path system comprises an air inlet pipe, one end of the air inlet pipe is communicated with the upper part of the shell flow pipe, and the other end of the air inlet pipe is communicated with the lower part of the shell flow pipe; the air inlet pipe is connected with a target air flow differential pressure transmitter. The pressure can be further adjusted through the absolute pressure transmitter, so that the detection result is more accurate. This application is through having increased target gas flow differential pressure changer in the pipeline of intake pipe, can adjust the air pressure differential at the both ends of intake pipe through target gas flow differential pressure changer to guarantee that the particle can be smooth from the bottom blowout of advance appearance pipe, reduced because the inaccurate error that brings of air current of intake pipe, make the measuring result more accurate.

Description

Aerosol particle size spectrometer analysis device

Technical Field

The invention relates to the technical field of aerosol analysis in atmospheric environment, in particular to an aerosol particle size spectrometer analysis device.

Background

Aerosol particles in the atmosphere directly or indirectly affect the earth's environment by absorbing or scattering radiation from the sun. For example, the particle size of 2.5 μm or less (PM2.5) in the atmospheric aerosol has a large specific surface area, strong chemical activity, and is liable to be accompanied by toxic and harmful substances (such as heavy metals, microorganisms, etc.), and can be suspended in the air for a long time, which poses a serious threat to human health, and thus has recently received great attention.

The aerosol particle laser analyzer with the publication number of CN101398367B adopts a laser mode to perform qualitative analysis on particles, but when sample gas enters the shell flow tube, because the gas inlet pipe enters the shell flow tube after being filtered, the flow of target gas flow cannot be accurately controlled, so that the pressure difference between the gas flow of the sample inlet pipe and the gas flow in the shell flow tube may be different, and the particles cannot be smoothly ejected from the nozzle.

Disclosure of Invention

The invention provides an analysis device for an aerosol particle size spectrometer, aiming at the problem that the air pressure difference between the air flow of an inlet pipe and the air flow in a shell flow pipe is different and particles cannot be smoothly sprayed out from a nozzle because the air in the inlet pipe is only pumped in by a pump at present.

In order to achieve the above purpose, the invention provides the following technical scheme:

an aerosol particle size spectrometer analysis device comprises a sample introduction system and a gas circuit system, wherein the sample introduction system comprises a sample introduction pipe and a shell flow pipe; a sealing plug is arranged in the middle of the shell flow tube, and the sample inlet tube penetrates through the sealing plug; the height of the shell flow pipe is higher than that of the sample inlet pipe; the gas path system comprises a gas inlet pipe, one end of the gas inlet pipe is communicated with the upper part of the shell flow pipe, and the other end of the gas inlet pipe is communicated with the lower part of the shell flow pipe; and a target gas flow differential pressure transmitter is connected in the gas inlet pipe. In order to ensure the stability of air inlet, one end of the air inlet pipe is connected to the upper part of the shell flow pipe, and the pressure can be further regulated through the absolute pressure transmitter, so that the detection result is more accurate.

Preferably, the air inlet pipe is sequentially connected with a first filter membrane, a target air flow pump and a second filter membrane in series according to the air inlet direction, two ends of the target air flow differential pressure transmitter are connected with the air inlet pipe in parallel, and the air inlet pipe is further provided with an absolute pressure transmitter. The target gas flow pump provides power for the gas flow of the gas inlet pipe, and particles in the gas are filtered through the first filter membrane and the second filter membrane, so that the gas entering the shell flow pipe is clean, and the detection result cannot be influenced by the particles.

Preferably, a flow limiting pore plate is arranged between the second filter membrane and the absolute pressure transmitter. And measuring the flow regulated by the target gas flow pump through the flow-limiting orifice plate.

Preferably, the gas circuit system further comprises an exhaust pipe, and a total sampler flow pressure difference transmitter is connected between the exhaust pipe and the gas inlet pipe. Increase the flow differential pressure transmitter of total sample thief and can accurate control the flow of admitting air and exhausting between blast pipe and intake pipe for the air current in the detection area is more stable, can not influence the testing result.

Preferably, the exhaust pipe is sequentially connected with a third filter membrane, a total sampling flow pump and a fourth filter membrane in series according to the exhaust direction; and the total sampler flow differential pressure transmitter is connected in parallel to one end of the third filter membrane far away from the total sampling flow pump. And the gas is pumped out through the total sampling flow pump, and circulation is formed between the total sampling flow pump and the gas inlet pipe, so that the gas flow in the detection area reaches a qualified gas flow value.

Compared with the prior art, the invention has the beneficial effects that: this application is through having increased target gas flow differential pressure changer in the pipeline of intake pipe, can adjust the air pressure differential at the both ends of intake pipe through target gas flow differential pressure changer to guarantee that the particle can be smooth from the bottom blowout of advance appearance pipe, reduced because the inaccurate error that brings of air current of intake pipe, make the measuring result more accurate.

Description of the drawings:

FIG. 1 is a schematic structural diagram of an analysis device of an aerosol particle size spectrometer provided herein;

fig. 2 is a schematic structural view of a restriction orifice plate.

The labels in the figure are: the method comprises the following steps of 1-shell flow tube, 2-sample inlet tube, 3-air inlet tube, 4-first filter membrane, 5-target air flow pump, 6-second filter membrane, 7-target air flow differential pressure transmitter, 8-absolute pressure transmitter, 9-accelerating nozzle, 10-flow limiting pore plate, 11-exhaust tube, 12-total sampler flow differential pressure transmitter, 13-third filter membrane, 14-total sampling flow pump, 15-fourth filter membrane, 16-sealing plug and 17-detection area.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the description of the present invention, it is to be understood that the terms "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention.

In the description of the present invention, unless otherwise specified and limited, it is to be noted that the terms "mounted," "connected," and "connected" are to be interpreted broadly, and may be, for example, a mechanical connection or an electrical connection, a communication between two elements, a direct connection, or an indirect connection via an intermediate medium, and specific meanings of the terms may be understood by those skilled in the art according to specific situations.

As shown in fig. 1, the present application provides an aerosol particle size spectrometer analysis device, which includes a sample injection system and a gas circuit system, wherein the sample injection system includes a sample injection tube 2 and a shell flow tube 1; a sealing plug 16 is arranged in the middle of the shell flow tube 1, and the sample inlet tube 2 penetrates through the sealing plug 16; the height of the shell flow pipe 1 is higher than that of the sample inlet pipe 2; the air path system comprises an air inlet pipe 3, one end of the air inlet pipe 3 is communicated with the upper part of the shell flow pipe 1, and the other end of the air inlet pipe 3 is communicated with the lower part of the shell flow pipe 1; the intake pipe 3 is connected with a target gas flow differential pressure transmitter 7.

The air inlet pipe 3 is sequentially connected with a first filter membrane 4, a target air flow pump 5 and a second filter membrane 6 in series according to the air inlet direction, two ends of a target air flow differential pressure transmitter 7 are connected with the air inlet pipe 3 in parallel, and an absolute pressure transmitter 8 is further arranged on the air inlet pipe 3. A flow-limiting orifice plate 10 is arranged between the second filter membrane 6 and the absolute pressure transmitter 8. The gas path system also comprises an exhaust pipe 11, and a total sampler flow pressure difference transmitter 12 is connected between the exhaust pipe 11 and the gas inlet pipe 3. The exhaust pipe 11 is sequentially connected with a third filter membrane 13, a total sampling flow pump 14 and a fourth filter membrane 15 in series according to the exhaust direction; a total sampler flow differential pressure transducer 12 is connected in parallel to the end of the third filter membrane 13 remote from the total sampling flow pump 14.

The flow-limiting orifice plate 10 is installed in the air inlet pipe 3, a flow-limiting hole is arranged in the middle of the flow-limiting orifice plate 10, as shown in fig. 2, the aperture of the flow-limiting hole is D, the pipe diameter of the air inlet pipe is D, the aperture D is smaller than the pipe diameter D, fluid shrinks when passing through the flow-limiting orifice plate, a minimum shrinking section is formed behind the flow-limiting orifice plate, and then liquid flow is expanded. The change in velocity will cause a change in pressure according to bernoulli's equation, and therefore the differential pressure across A, B before and after the orifice plate is measured, allowing the air flow velocity and flow through the duct to be calculated. The orifice plate 10 is used to measure the flow rate regulated by the target gas flow pump 5.

The bottom of the sampling tube 2 is provided with an acceleration nozzle 9, and the acceleration nozzle 9 is small in size to eject aerosol particles one by one from the acceleration nozzle 9. The aerosol sample introduction pipe 2 is vertically arranged, so that aerosol particles sprayed out of the acceleration nozzle 9 vertically penetrate through the laser spot as much as possible. The filtered clean air is sent into the shell flow pipe 12 to form a shell for wrapping the sample flow, and aerosol particles immediately surround the shell after being sprayed out from the accelerating nozzle 9 to prevent the aerosol particles from diffusing to the periphery, so that the sample particles fly along a straight line. The target gas flow differential pressure transmitter 7, the absolute pressure transmitter 8, and the total sampler flow differential pressure transmitter 12 are existing transmitters.

The aerosol particle size spectrometer analysis device also comprises an optical path system and a photoelectric detection system. The light path part comprises two groups of laser light sources, wherein one double-slit red light excitation light source forms a double-peak red light laser light path, the other double-slit red light excitation light source is an ultraviolet pulse laser light source, and an ultraviolet pulse laser starting device is configured. The double-peak red light path is shaped by the optical system and then passes through the right lower part of the nozzle to be used for detecting the flight time of ions; because the ions of different sizes pass through the accelerating nozzle 9 at different speeds, the flight times of the ions flying through the double-peak red light spots are different, the aerodynamic diameter of the particles can be calculated by detecting the flight time of the ions flying through the double-peak red light spots, and the number of the particles can be counted. The ultraviolet pulse laser light source passes through the right lower part of the double-peak red light path which is just opposite to the nozzle and is used for exciting fluorescence emitted by biological particles and further detecting active biological particles in the aerosol. The particles with different sizes pass through the particle accelerating nozzle 9, the obtained speeds are different, the flight time of the particles flying through the double-peak red light spots is also different, and the aerodynamic diameters of the particles are calculated by detecting the flight time of the particles flying through the double-peak red light spots.

After the particles pass through the double-peak red light laser, calculating the pulse triggering time of the ultraviolet laser according to the flight speed of the particles, emitting ultraviolet pulse laser irradiation at proper time, and emitting fluorescence with specific wavelength by the inherent luminescent substance in the active biological particles under the irradiation of the laser with the specific wavelength; the ultraviolet scattered light and the fluorescence emitted by the biological particles are focused by another ellipsoidal mirror, and then the red light and the ultraviolet light are filtered by an optical filter.

The working process is as follows: the method comprises the following steps that airflow to be detected enters the upper part of a shell flow pipe 1, one part of the airflow enters through a sample inlet pipe 2, the other part of the airflow enters an air inlet pipe 3 under the action of a target gas flow pump 5, clean air enters into the shell flow pipe 1 after being filtered by a first filter membrane 4 and a second filter membrane 6, airflow wrapping the sample inlet pipe 2 is formed, and aerosol particles immediately surround the aerosol particles after being sprayed out of an accelerating nozzle 9, so that the aerosol particles are prevented from diffusing to the periphery, and the sample particles fly along a straight line; the bottom exhaust pipe 11 exhausts the gas in the detection area 17 under the action of the total sampling flow pump 14, so that the gas flow in the detection area 17 forms a circulation. The total air inflow flow, the flow of the sample gas in the sample inlet pipe 2 and the adjustment and control of the target gas flow can be accurately controlled through the target gas flow differential pressure transmitter 7, the absolute pressure transmitter 8 and the total sampler flow differential pressure transmitter 12, so that the detection accuracy is improved through adjusting the gas flow under different environments, and errors caused by inaccurate gas flow are reduced.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. An analysis device of an aerosol particle size spectrometer is characterized by comprising a sample introduction system and a gas circuit system, wherein the sample introduction system comprises a sample introduction pipe (2) and a shell flow pipe (1); a sealing plug (16) is arranged in the middle of the shell flow pipe (1), and the sampling pipe (2) penetrates through the sealing plug (16); the height of the shell flow pipe (1) is higher than that of the sample inlet pipe (2); the gas path system comprises a gas inlet pipe (3), one end of the gas inlet pipe (3) is communicated with the upper part of the shell flow pipe (1), and the other end of the gas inlet pipe (3) is communicated with the lower part of the shell flow pipe (1); and a target gas flow differential pressure transmitter (7) is connected in the gas inlet pipe (3).

2. The aerosol particle size spectrometer analysis device according to claim 1, characterized in that the inlet tube (3) is connected in series with a first filter membrane (4), a target gas flow pump (5) and a second filter membrane (6) in sequence according to the inlet direction, both ends of the target gas flow differential pressure transducer (7) are connected in parallel with the inlet tube (3), and the inlet tube (3) is further provided with an absolute pressure transducer (8).

3. The aerosol particle spectrometer analysis device according to claim 2, characterised in that a restriction orifice (10) is provided between the second filter membrane (6) and the absolute pressure transducer (8).

4. The aerosol particle spectrometer analysis device according to claim 1, characterised in that the gas circuit system further comprises an exhaust pipe (11), and a total sampler flow pressure difference transmitter (12) is connected between the exhaust pipe (11) and the inlet pipe (3).

5. The aerosol particle size spectrometer analysis device according to claim 4, characterised in that the exhaust pipe (11) is connected in series with a third filter membrane (13), a total sampling flow pump (14) and a fourth filter membrane (15) in sequence according to the exhaust direction; the total sampler flow differential pressure transmitter (12) is connected in parallel to one end of the third filter membrane (13) far away from the total sampling flow pump (14).