AU2021104554A4

AU2021104554A4 - Electrostatic Aerosol Particle Sampler

Info

Publication number: AU2021104554A4
Application number: AU2021104554A
Authority: AU
Inventors: Gang Chen; Chenglong Li; Xin Qin; Li Sun; Jinguang ZHANG; Tiening Zhang; Shuhui Zhao; Deping Zhou
Original assignee: Liaoning Weather Modification Office; Shenyang Institute Of Atmospheric Environment China Meteorological Administration
Current assignee: Liaoning Weather Modification Office; Shenyang Institute Of Atmospheric Environment China Meteorological Administration
Priority date: 2021-07-26
Filing date: 2021-07-26
Publication date: 2021-10-07
Anticipated expiration: 2029-07-26

Abstract

The invention provides an electrostatic aerosol particle sampler. The invention relates to the technical field of environmental sampling and solves the problem of low sampling efficiency of nano-scale aerosol in the prior art. The invention comprises a sampling head, an electrostatic generator and sampling sheets. The sampling head is an insulating structural member with a cavity inside, and is provided with an air inlet and an air extraction port communicated with the cavity, and the sampling head is provided with threading holes for threading positive and negative power cords. The electrostatic generator is installed in the cavity of the sampling head and connected with a high voltage power supply. The sampling sheets are installed in the cavity of the sampling head and are arranged in the discharge areas of the electrostatic generator. The method is suitable for collecting and sampling nano-scale aerosol particles. It also has the advantage of high sampling efficiency of nano-scale aerosol particles. 1/2 FIGURES 4 -15 21 /1 24 23 3 12 5 Figure 1

Description

1/2

FIGURES

4

-15

21 /1

24 23 3

12

5

Figure 1

Electrostatic Aerosol Particle Sampler

TECHNICAL FIELD

The invention relates to the technical field of environmental sampling, particularly to an

electrostatic aerosol particle sampler.

BACKGROUND

Atmospheric aerosol refers to solid and liquid particles suspended in the atmosphere.

Atmospheric aerosols can reduce the visibility of the atmosphere and even form haze

weather, which has adverse effects on the ambient air quality and endangers human

health. Especially, ultra-fine particles below 1 micron can be absorbed directly into the

blood circulation system through the lungs. In addition, from the regional and global

scales, aerosols not only change the global energy distribution and balance by scattering

and absorbing solar radiation, but also can act as cloud condensation nuclei and ice nuclei

to influence cloud, fog and precipitation processes, thus affecting global climate change.

The observation and study of aerosol physical and chemical properties is the basis for

people to understand the formation process of cloud precipitation and reveal the source of

pollutant. It is also the scientific basis for implementing air pollution control and

artificially influencing weather.

Therefore, scientists and technicians have developed a variety of aerosol membrane

sampling devices, including large/medium flow aerosol samplers, microbial aerosol

samplers, and multi-stage aerosol samplers with different particle sizes. The main

principle is to use a sampling air pump to pump ambient air at a certain speed and make it

pass through filter membranes made of different materials, so as to intercept aerosol

particles in the air onto the filter membranes. Then take the sampling diaphragms to the laboratory for physical property measurement, detection and/or chemical composition analysis. Aerosol filter membrane sampling has been widely used in a variety of scientific research and environmental monitoring business.

At present, the manual sampler of ambient air aerosol widely used in China is mainly an

impact dynamic sampling device. It uses a sampling air pump to extract ambient air at a

certain speed and intercept aerosol particles in the air to the filter membrane. At present,

the minimum pore size of the commonly used organic filter membrane is 0.1 micron

(mostly 0.22 micron and 0.45 micron). When the impact dynamic sampling device is

used for sampling with filter membrane of aerosol particles larger than 0.1 micron, the

collection efficiency can reach more than 97%. It can meet the requirements of scientific

experiments. However, when the ultra-fine aerosol particles whose particle size is close

to or even smaller than 0.1 micron, especially smaller than 0.01 micron (nano-scale) are

sampled with the filter membrane by the impact dynamic sampling device, the device

will make the particles easily penetrate the pore size of the filter membrane and be

difficult to be trapped on the filter membrane. As a result, the collection efficiency is low

(generally no more than 50%), and it is difficult to achieve the collection efficiency of

over 90%. This not only cannot meet the precise requirements of scientific experiments,

but also is difficult to meet the general business needs.

SUMMARY

The object of the present invention is to design an electrostatic aerosol particle sampler. It

is suitable for collecting and sampling nano-scale aerosol particles and has the advantage

of high sampling efficiency of nano-scale aerosol particles.

The invention is realized by the following technical scheme.

An electrostatic aerosol particle sampler comprises a sampling head, an electrostatic

generator and sampling sheets. The sampling head is an insulating structural member

with a cavity inside. The sampling head is provided with an air inlet and an air extraction

port communicated with the cavity, and the sampling head is provided with threading

holes for threading positive and negative power cords. The electrostatic generator is

installed in the cavity of the sampling head and connected with a high voltage power

supply. The sampling sheets are installed in the cavity of the sampling head and are

arranged in the discharge areas of the electrostatic generator.

With the above arrangement, the electrostatic generator is arranged inside the sampling

head. The positive and negative electrodes connected with the high voltage power supply

generate discharge to form discharge areas. The discharge areas are high voltage

electrostatic dust collection areas. When the sampling sheets are placed in the high

voltage electrostatic dust collection areas, aerosol particles can be collected by

electrostatic adsorption method. The method improves the collection efficiency,

especially for ultra-fine particles smaller than 0.01 micron. The collection efficiency can

reach over 99%.

Further, in order to better realize the invention, the following arrangement structure is

adopted. The air inlet is arranged at the top of the sampling head, and the air extraction

port is arranged at the bottom of the sampling head.

Furthermore, in order to better realize the invention, the following arrangement structure

is particularly adopted. The electrostatic generator comprises a high voltage power supply

positive electrode fixing plate, metal needles and tray bases.

The high voltage power supply positive electrode fixing plate is an insulating structural

member. It is arranged above the tray bases and blocks the air path from the air inlet to

the air extraction port. The top surfaces of the tray bases are provided with the sampling

sheets. The metal needles are hollow and inserted into the high voltage power supply

positive electrode fixing plate. The tips of the metal needles point to the sampling sheets.

Further, in order to better realize the invention, the following setting structure is adopted.

The tips of the metal needles point to the centers of the sampling sheets.

is adopted. The bottom of the cavity of the sampling head is connected with height

adjusting bolts. The tray bases are installed on the height adjusting bolts to adjust the

distances between the tray bases and the tips of the metal needles.

With the above arrangement structure, the heights of the tray bases can be changed by

adjusting the height adjusting bolts, and the distances between the sampling sheets and

the tips of the metal needles can be realized.

is particularly adopted. A plurality of metal needles are arranged, and all the metal

needles are independently arranged on the high voltage power supply positive electrode

fixing plate. The tray bases and the metal needles are arranged in the same number and

correspond to each other one by one. Each tray base is provided with one sampling sheet.

With the above arrangement, a high voltage electrostatic dust collection area is created

between each pair of tray bases and metal needles. Multiple sampling sheets can be

collected at one time during sampling, which can improve the collection efficiency of

samples, thereby improving the accuracy of observation and/or detection data.

Meanwhile, the collected multiple samples are convenient for comparative analysis of

different physical and chemical properties of aerosol particles, therefore the reliability of

analysis and comparison data can be improved.

is particularly adopted. Four metal needles are arranged, and the four metal needles are

arranged at equal angles around a center point.

Further, in order to better realize the present invention, the following arrangement

structure is particularly adopted. Among all the sampling sheets, different sampling

sheets can be made of the same material or different materials.

With the above-mentioned structure, the sampling sheets can adopt metal diaphragms or

organic/inorganic porous filter membranes according to the analysis needs of different

physical and chemical properties.

particularly adopted. The sampling head comprises an upper main body shell and a lower

main body shell which are arranged up and down. The upper main body shell is

detachably connected with the lower main body shell, and the upper main body shell and

the lower main body shell are connected to form the cavity. The air inlet is arranged on

the upper main body shell, and the air extraction port is arranged on the lower main body

shell.

adopted. The bottom of the upper main body shell is connected with the top of the lower

main body shell in a nested structure.

is adopted. A handle is arranged at the top of the upper main body shell. The bottom of

the lower main body shell is provided with a whole fixing hole.

is particularly adopted. A flowmeter connecting nozzle is inserted into the air extraction

port. A flowmeter and an air pump are sequentially connected on an air path starting from

the flowmeter connecting nozzle.

The invention has the following advantages and beneficial effects.

In the invention, the electrostatic generator is arranged inside the sampling head, and the

positive and negative electrodes connected with the high voltage power supply generate

discharge to form discharge areas. The discharge areas are a high voltage electrostatic

dust collection areas. When the sampling sheets are placed in the high voltage

electrostatic dust collection areas, aerosol particles can be collected by electrostatic

adsorption method. The method improves the collection efficiency, especially for ultra

fine particles less than 0.01 micron. The collection efficiency can reach over 99%.

According to the invention, a high voltage electrostatic dust collection area is generated

between each pair of tray bases and metal needles. Therefore, a plurality of sampling

sheets can be collected at one time during sampling, which can improve the collection

efficiency of samples, thereby improving the accuracy of observation and/or detection

data. Meanwhile, the collected samples are convenient for comparative analysis of

different physical and chemical properties of aerosol particles, and the reliability of

analysis and comparison data can be improved.

BRIEF DESCRIPTION OF THE FIGURES

In order to explain the embodiments of the present invention or the technical scheme in

the prior art more clearly, the drawings required in the embodiments or the description of

the prior art will be briefly introduced below. Obviously, the drawings in the following

description are only some embodiments of the present invention, and other drawings can

be obtained according to these drawings for ordinary technicians in the field without

paying creative labor.

Figure 1 A schematic structural diagram of an electrostatic aerosol particle sampler

Figure 2 A schematic diagram of the principle of electrostatic aerosol particle sampler

The figure is marked as follows.

1. Sampling head; 11. Upper main body shell; 12. Lower main body shell; 13. Air inlet;

14. Air extraction port; 15. Positive power cord threading hole; 16. Negative power cord

threading hole;

2. Electrostatic generator; 21. High voltage power supply positive electrode fixing plate;

22. Metal needle; 23. Tray base; 24. Metal tray;

3. Sampling sheet; 4. Handle; 5. Flowmeter connecting nozzle; 6. Height adjusting bolts.

DESCRIPTION OF THE INVENTION

In order to make the purpose, technical scheme and advantages of the present invention

clearer, the technical scheme of the present invention will be described in detail below.

Obviously, the described embodiments are only part of the embodiments of the present

invention, not all of them. Based on the embodiments of the present invention, all other

embodiments obtained by ordinary technicians in the field without creative labor belong

to the scope of protection of the present invention.

In the description of the present invention, it should be noted that, unless otherwise

specified, "multiple" means two or more. The terms "upper", "lower", "left", "right",

"inner", "outer", "front end", "back end", "head" and "tail" indicate the orientation or

positional relationship based on the orientation or positional relationship shown in the

drawings, which is only for convenience of describing the invention and simplifying the

description, but does not indicate or imply that the referred devices or elements must be

specific. In addition, the terms "first", "second", "third", etc., are used for descriptive

purposes only and cannot be understood as indicating or implying relative importance.

In the description of the present invention, it should be noted that unless otherwise

specified and limited, the terms "installation", "connected" and "connection" should be

understood in a broad sense. For example, they can be fixed connection, detachable

connection or integrated connection. They can be mechanical connection or electrical

connection. They can also be direct connection or indirect connection through an

intermediate medium. For ordinary technicians in the field, the specific meanings of the

above terms in the practical novel can be understood according to specific conditions.

Embodiment 1:

An electrostatic aerosol particle sampler is suitable for collecting and sampling nano

scale aerosol particles. It has the advantage of high sampling efficiency of nano-scale

aerosol particles. As shown in Figure 1 and Figure 2, it is specially arranged in the

following structure.

Basically, the electrostatic aerosol particle sampler comprises a sampling head 1, an

electrostatic generator 2 and a sampling sheet 3.

Sampling head 1 is an insulating structural member made of polyethylene and other

plastics, and its appearance is approximately cylindrical. It includes upper main body

shell 11 and lower main body shell 12 arranged up and down. The bottom of upper main

body shell 11 and the top of lower main body shell 12 are connected in a nested structure.

When the upper main body shell 11 and the lower main body shell 12 are connected, an

internal cavity is formed, and the cavity is approximately cylindrical. The top center of

the upper main body shell 11 is provided with an air inlet 13 communicating with the

cavity. The top side of the upper main body shell 11 is provided with a positive power

cord threading hole 15 for threading a power cord. The bottom center of the lower main

body shell 12 is provided with an air extraction port 14 communicated with the cavity. A

negative power cord threading hole 16 for threading a negative power cord is formed at

the bottom side of the lower main body shell 12. The air inlet 13 of the upper main body

shell 11 bulges upwards to form an air intake. The opening of the air intake is located at

the side of the air intake, and a handle 4 is fixed at the top of the air intake. The bottom of

the lower main body shell 12 is provided with a plurality of integral fixing holes 7.

The electrostatic generator 2 can adopt the existing device. It is arranged in the cavity of

the sampling head 1 and detachably and fixedly connected with the inner wall of the

sampling head 1. The electrostatic generator 2 is connected with the positive and negative

electrodes of the high voltage power supply through the positive power cord threading

hole 15 and the negative power cord threading hole 16.

The sampling sheet 3 is installed in the cavity of the sampling head 1, and the sampling

sheet 3 is arranged in the discharge area of the electrostatic generator 2.

In the above arrangement structure, the electrostatic generator 2 is arranged inside the

electrodes of the high voltage power supply to generate a discharge to form a discharge

area. The discharge area becomes a high voltage electrostatic dust collection area. When

the sampling sheet 3 is placed in the high voltage electrostatic dust collection area,

aerosol particles can be collected by electrostatic adsorption method. This arrangement

can solve the problem that some aerosol particles will be sucked into the pore size of the

filter membrane when sampling by using the prior art, especially the nano-scale particles

are easy to penetrate through the diaphragm of the filter membrane and are not easy to be

collected on the filter membrane. Therefore it can improve the collection efficiency,

reach over 99%.

Embodiment 2:

This embodiment is further optimized on the basis of the above embodiment. In order to

better realize the present invention, the following arrangement structure is especially

adopted.

In this embodiment, the electrostatic generator 2 specifically includes a high voltage

power supply positive electrode fixing plate 21, a metal needle 22 and a tray base 23.

The high voltage power supply positive electrode fixing plate 21 is a circular insulating

plate. It is embedded in the upper main body shell 11 and fixed at the upper main body

shell 11 by three evenly distributed screws. The high voltage power supply positive

electrode fixing plate 21 blocks the air path from the air inlet 13 to the air extraction port

14. The high voltage power supply positive electrode fixing plate 21 is disposed right

above the tray base 23.

The tray base 23 is connected to the inner wall of the lower main body shell 12, and the

top surface of the tray base 23 is provided with a circular groove. A circular sampling

sheet 3 is placed in the groove or a circular metal tray 24 is placed in the groove and a

sampling sheet 3 is placed on the metal tray 24. The negative power cord penetrates

through the negative power cord threading hole 16 and is connected to the tray base 23.

A hollow metal needle 22 with an pore size of 1.6mm is inserted into the center of the

high voltage power supply positive electrode fixing plate 21. The tip of the metal needle

22 points downward to the center of the sampling sheet 3 with a height distance of 25

mm. The positive power cord penetrates through the positive power cord threading hole

and is connected with the metal needle 22.

In the above arrangement structure, the electrostatic generator 2 is embedded in the upper

main body shell 11 by a circular insulating plate as a fixing plate for the positive

electrode of the high voltage power supply. A metal needle (medical syringe needle can

be used) connected to the positive electrode of the high voltage power supply passes

through the high voltage power supply positive electrode fixing plate 21, and the tip

points to the center of the tray base 23. The negative electrode of the high voltage power

supply is connected to the tray base 23. In this way, after the power supply is turned on,

tip discharge is formed by the high voltage electrode, and a high voltage electrostatic dust

collection area is formed in the area of the tray base 23.

Embodiment 3:

This embodiment is further optimized on the basis of the above embodiments. In order to

adopted.

A vertically arranged height adjusting bolt 6 is connected to the bottom of the inner wall

of the lower main body shell 12, and the tray base 23 is mounted on the height adjusting

bolt 6. The distance between the tray base 23 and the tip of the metal needle 22 is

adjusted by adjusting the height adjusting bolt 6.

In the above arrangement structure, the height of the tray base 23 can be changed by

adjusting the height adjusting bolt 6, and the distance between the sampling sheet 3 and

the tip of the metal needle 22 can be realized. Therefore ensuring that the effective range

of tip discharge as the positive electrode of the high voltage power supply completely

covers the circular area of the tray.

Embodiment 4:

adopted.

In this embodiment, there are four metal needles 22. All of the metal needles 22 are

independently arranged on the high voltage power supply positive electrode fixing plate

21. The four metal needles 22 are arranged at equal angles around the center point of the

high voltage power supply positive electrode fixing plate 21. Accordingly, the tray bases

23 and the metal needles 22 are arranged in the same number and form four pairs in one

to-one correspondence. Each of the four 51mm round stainless steel tray bases 23 is

provided with a sampling sheet 3.

Among all the sampling sheets 3, different sampling sheets 3 can be made of the same

material or different materials. Metal diaphragms or organic/inorganic porous filter

membranes can be used according to the analysis needs of different physical and

chemical properties.

In the above arrangement structure, the arrangement structure of four pairs of tray bases

23 and metal needles 22 can generate four high voltage electrostatic dust collection areas

in the sampling head. Four samples can be collected at one time during sampling, which

can improve the collection efficiency of samples, thereby improving the accuracy of

observation and/or detection data. At the same time, the collected sampling sheets are

convenient for comparative analysis of different physical and chemical properties of

aerosol particles, therefore the reliability of analysis and comparison data can be

improved.

Embodiment 5:

adopted.

A flowmeter connecting nozzle 5 is inserted at the air extraction port 14. At the same

time, a flowmeter and an air pump are connected in turn on the air path starting from the

flowmeter connecting nozzle 5.

The flowmeter adopts the product sold in the market. One end of the flowmeter is

connected with the air pump through plastic pipe or rubber pipe, and the other end is

connected with the flowmeter connecting nozzle 5 through plastic pipe or rubber pipe.

The flowmeter can adjust and determine the sampling flow through buttons, and display

the total flow of each sampling.

The air pump adopts the equipment sold in the market and is powered by a small motor.

The working voltage of the small motor is AC 220V(50HZ) and the load capacity is

above 1.5 kW. The air pump is connected with the flowmeter through a plastic pipe or a

rubber pipe, and can provide 0.2-25.OL sampling flow per minute.

The electrostatic aerosol particle sampler is mainly composed of an air pump, a

flowmeter, a sampling head 1, an electrostatic generator 2 and sampling sheets 3. The air

pump sucks ambient air into the sampling head 1 at a fixed flow rate from the air inlet 13,

and the air flows from the holes of the metal needles 22 to the lower part of the high

voltage power supply positive electrode fixing plate 21. The flowmeter controls and

displays the amount of air passing through the areas where the sampling sheets 3 are

located. The sampling head 1 is built with four stainless steel tray bases 23. The tray

bases 23 are provided with metal trays 24. The metal trays 24 are located in the

electrostatic dust collection areas. The electrostatic generator 2 uses 10 kV high voltage

current to generate the electrostatic dust collection areas through the tip discharge effect.

Sampling sheets 3 are placed on metal trays 24 for collecting aerosol particles in ambient

air. The electrostatic aerosol particle sampler can solve the problem that a part of aerosol

particles are sucked into the pore size of the filter membrane when sampling by using the

prior art, especially nano-scale particles are easy to penetrate through the diaphragm of

the filter membrane but not easy to be collected on the filter membrane. It can also

improve the collection efficiency, especially for ultra-fine particles smaller than 0.01

micron. The collection efficiency can reach over 99%.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. An electrostatic aerosol particle sampler, characterized by comprising a sampling head

(1), an electrostatic generator (2) and sampling sheets (3);

The sampling head (1) is an insulating structural member with a cavity inside, and the

sampling head (1) is provided with an air inlet (13) and an air extraction port (14) which

are communicated with the cavity, and the sampling head (1) is provided with threading

holes for threading positive and negative power cords;

The electrostatic generator (2) is installed in the cavity of the sampling head (1);

The sampling sheets (3) are installed in the cavity of the sampling head (1) and are

arranged in the discharge areas of the electrostatic generator (2).

2. The electrostatic aerosol particle sampler according to Claim 1, characterized in that

the air inlet (13) is arranged at the top of the sampling head (1), and the air extraction port

(14) is arranged at the bottom of the sampling head (1).

3. The electrostatic aerosol particle sampler according to Claim 2, characterized in that

the electrostatic generator (2) comprises a high voltage power supply positive electrode

fixing plate (21), metal needles (22) and tray bases (23);

The high voltage power supply positive electrode fixing plate (21) is an insulating

structural member; it is arranged above the tray bases (23) and blocks the air path from

the air inlet (13) to the air extraction port (14);

The top surfaces of the tray bases (23) are provided with the sampling sheets (3);

The metal needles (22) are hollow and inserted into the high voltage power supply

positive electrode fixing plate (21), and the tips of the metal needles (22) point to the

sampling sheets (3).

4. The electrostatic aerosol particle sampler according to Claim 3, characterized in that

height adjusting bolts (6) are connected to the bottom of the cavity of the sampling head

(1), and the tray bases (23) are installed on the height adjusting bolts (6) to adjust the

distances between the tray bases and the tips of the metal needles (22).

5. The electrostatic aerosol particle sampler according to Claim 3, characterized in that a

plurality of metal needles (22) are arranged, and all the metal needles (22) are

(21); The tray bases (23) and the metal needles (22) are arranged in the same number and

correspond to each other one by one, and each tray base (23) is provided with a sampling

sheet (3).

6. The electrostatic aerosol particle sampler according to Claim 5, characterized in that

there are four metal needles (22), and the four metal needles (22) are arranged at equal

angles around a center point.

7. The electrostatic aerosol particle sampler according to Claim 1, characterized in that

the sampling head (1) comprises an upper main body shell (11) and a lower main body

shell (12) which are arranged up and down; The upper main body shell (11) is detachably

connected with the lower main body shell (12), and the upper main body shell (11) and

the lower main body shell (12) are connected to form the cavity;

The air inlet (13) is arranged on the upper main body shell (11), and the air extraction

port (14) is arranged on the lower main body shell (12).

8. The electrostatic aerosol particle sampler according to Claim 7, characterized in that

the bottom of the upper main body shell (11) is connected with the top of the lower main

body shell (12) in a nested structure.

9. The electrostatic aerosol particle sampler according to Claim 7, characterized in that a

handle (4) is arranged at the top of the upper main body shell (11).

10. The electrostatic aerosol particle sampler according to Claim 7, characterized in that:

a flowmeter connecting nozzle (5) is inserted into the air extraction port (14); A

flowmeter and an air pump are sequentially connected on an air path starting from the

flowmeter connecting nozzle (5).

FIGURES 1/2

Figure 1