KR20190000470A - Differential mobility analyzer and calibrating system for nano particle measuring device using thereof - Google Patents

Abstract

The present invention provides a flow path of a mixture of an aerosol and a protective gas, which is charged with polydisperse particles, between opposite electrodes, an electric mobility of the charged polydisperse particles is used by an electric field formed between the opposite electrodes to classify the polydisperse particles into monodisperse particles having a target particle size by using a differential mobility analyzer, and has a surface of at least one of the opposite electrodes facing at least the other electrode made of an insulator.

Description

TECHNICAL FIELD [0001] The present invention relates to a mobility deviation analyzer and a calibration system for a nanoparticle measuring device using the same,

The present invention relates to a differential mobility analyzer (DMA) for classifying polydisperse nanoparticles by electrostatic force, and a nanoparticle measuring apparatus capable of discriminating and correcting the reliability of a nanoparticle measuring apparatus using the same.

As disclosed in Patent Document 1, a differential mobility analyzer (DMA) is used for accurately classifying fine particles having a diameter of 1 to 1000 nm. Particularly, it has been used for sorting and supplying monodisperse nanoparticles or as a size classifier for measuring the size distribution of nanoparticles.

As shown in Fig. 10, the mobility deviation analyzer includes a polydisperse particle inlet through which aerosols as charged polydisperse particles are introduced, and an inlet of dilution protective air that can carry particles in laminar flow by the laminar flow forming filter . As shown in Fig. 10, when the inside of the mobility deviation analyzer is briefly represented as a space between two coaxial metal tubes having different radii r1 and r2, clean sheath air passing through the filter is further transferred to the inside of Qsh (Particleladen air) is flowed at the flow rate Qa, while the air is flowed at the flow rate, while the particles are suspended in the outer space separated by the short tube.

At this time, negative voltage V is applied to the inner metal tube (radius r1) (high voltage electrode) and the outer metal pipe (radius r2) is grounded. As a result, the positively charged particles gradually move to the inner metal tube by the electric field while moving downstream by a uniform flow field between the inner metal tube and the outer metal tube. That is, during the time (residence time) during which the particles move from the inlet to the outlet of the inner metal tube at the same flow rate as the flow due to the flow moving downstream, the gas is accelerated electrically toward the inner metal tube to reach the outlet hole of the final inner metal tube Particles of the same specific size to be supplied are finally classified and supplied.

Patent Document 1: Korean Patent No. 10-0991023 (October 29, 2010)

In the case of the above-described conventional mobility deviation analyzer, it is advantageous to classify and supply specific monodisperse particles by using the electric mobility of the particles. However, as the particle size is reduced to nanosize, The classification performance is remarkably deteriorated at a particle diameter of 50 nm or less.

The mobility deviation analyzer requires a distance of about 10 mm between the electrodes where the device is expensive and the nanoparticles are moved due to the fear of sparking. Therefore, when the nanoparticles of the same size are classified, . In addition, since a high electric field should be applied at a distance of 10 mm and a high flow rate of protected air must be used in order to reduce the residence time, a high voltage supply device of a high capacity of up to about 10 kV is required, and an air blower, .

On the other hand, in order to classify nanoparticles precisely, it is necessary to reduce the moving distance of the charged particles or to increase the flow rate to reduce the residence time of moving aerosols or protective air. However, since the distance between the electrodes is required to be at least about 10 mm or more due to the fear of generation of spark discharge, there is a limit to the nanoparticle classifying performance of the apparatus and the downsizing of the apparatus.

In addition, the conventional mobility error analyzer has to increase the cross-sectional velocity of the air passing through the device, since charged particles in the device must flow into the device to reduce the residence time in the electric field, The flow rate of the air including the supplied particles is required, so that it is difficult to downsize the apparatus and the capacity of the blower or the like for supplying air of several tens l / m has to be increased.

In addition, as the nano-sized charged particle moves through the space of 10 mm gap between the electrodes, the probability of classifying only the nanoparticles of exactly the same size due to the influence of diffusion becomes lower, Since not only low but also relatively large or small particles are included and classified, there is a limit to precisely classifying and supplying nanoparticles of the same size because deviation occurs in the classified particles.

In recent years, in order to measure indoor fine dust or the like, there are many cases where a nanoparticle measuring device is provided in a nationwide measuring station or a public place of a weather station. Even in the case where an abnormality occurs in such a nanoparticle measuring device, It is difficult to judge whether or not the abnormality exists in real time. In addition, even in the case of detecting an abnormality of the apparatus, since the measuring apparatus has to be sent to the manufacturer for calibrating it, there has been a problem that the operation cost of the apparatus is greatly increased especially when the manufacturer is located in another country

According to an aspect of the present invention, there is provided a mobility deviation analyzer comprising a flow path of a mixture of aerosols and a protective gas, which are charged polydisperse particles, between opposing electrodes, and an electric field formed between opposing electrodes Wherein at least one of the electrodes facing each other is classified into at least one of the electrodes of at least one of the other electrodes, Is made of an insulator.

According to one aspect of the present invention, the mobility deviation analyzer comprises: an outer cylinder into which a gas containing an aerosol containing charged polydisperse particles and a protective gas flow; an outer cylinder extending in the longitudinal direction of the outer cylinder; An inner electrode forming a flow path of a mixed gas of a gas containing an aerosol and a protective gas and an inner electrode forming an electric field, and a monodisperse particle outlet through which the monodisperse particles are discharged from the flow path.

According to one aspect of the present invention, the insulator may be formed on at least one surface of the outer cylinder or the inner electrode.

According to an aspect of the present invention, the outer cylinder and the inner electrode may be cylindrical hollow members extending in the longitudinal direction.

According to one aspect of the present invention, the polydisperse particle inlet through which the charged polydisperse particles are introduced into the outer cylinder is formed by slanting the wall portion of the outer cylinder at the upstream side of the flow passage, And the wall portion of the internal electrode may be formed to pass through the channel at a downstream side in an inclined manner.

According to an aspect of the present invention, the protective gas flows into the outer cylinder at the front end and the rear end in the longitudinal direction of the outer cylinder, and the polydisperse particle inlet through which the charged polydisperse particles are introduced into the outer cylinder is , And the wall portion of the outer cylinder may be formed obliquely through the wall portion of the outer cylinder in the direction in which the protective gas flows in the upstream side and the downstream side of the flow passage respectively, Between the particle entrance and the wall of the internal electrode.

According to one aspect of the present invention, the distance between the opposed electrodes is preferably 2 mm to 8 mm.

According to one aspect of the present invention, it is preferable that a voltage applied to maintain an electric field between the opposing electrodes is 5 kV or less.

According to another aspect of the present invention, there is provided a calibration system for a nanoparticle measuring device, comprising: a nanoparticle generating device for generating charged nanostructured nanoparticles. A flow path of a mixture of an aerosol and a protective gas, which is a charged polydisperse particle generated by the nanoparticle generating device, is provided between opposing electrodes, and an electric field formed between opposing electrodes is used to electrically A mobility deviation analyzer for primarily classifying polydisperse particles into mono-dispersed particles having a desired particle size using the mobility, and a calibrating nanoparticle measuring device for measuring monodispersed particles generated from the mobility deviation analyzer , And at least one of the opposite electrodes of the mobility deviation analyzer is characterized in that at least the surface facing the other electrode is made of an insulator.

According to one aspect of the present invention, there is provided a nanoparticle generating apparatus according to the nano particle generating apparatus, comprising: a body formed with an internal space and having an electric insulator inserted from one side into the internal space; A first inlet provided in the main body for introducing outside air into the inside of the heat insulating tube, a second inlet provided in the main body for introducing outside air into the heat insulating tube and the main body, And a nano particle generating device provided in the main body for discharging the air introduced into the main body through the heat insulating tube to the outside of the main body.

According to an aspect of the present invention, a mixed air uniform distribution unit for uniformly guiding the flow of the external air introduced into the body through the first inlet to the heat insulating tube may be provided, The upper and lower holes may be formed to guide the outside air upward and downward with respect to the center of the main body of the main body. In order to uniformly guide the flow of the outside air introduced into the main body through the second inlet to the end of the main body, Shaped dilution air uniform distribution unit may be provided between the dilution air uniform distribution unit and the dilution air uniform distribution unit may be perforated at regular intervals to form an annular shape.

According to another aspect of the present invention, the length of the local heating device may be equal to or shorter than the length of the heat insulating tube, the heat radiating window may be formed annularly along the body, And the end of the local heating device may be positioned, and the heat output window may be formed of a transparent material such as quartz or tempered glass, and the local heating device may be cylindrical.

The mobility error analyzer according to the present invention can significantly reduce the distance between electrodes for forming an electric field by applying an electrode having an insulator, thereby enabling operation of the mobility deviation analyzer even at a low flow rate.

Therefore, it is possible to reduce the size and weight of the mobility deviation analyzer, and to miniaturize the associated parts such as the blower and the HEPA filter, and to reduce the capacity.

In addition, as the distance between the electrodes decreases, the moving distance of the particles also decreases, so that the classification efficiency of the nanoparticles can be improved and the applied voltage for forming the same electric field can be reduced to about 1/4.

Further, according to the calibration system of the nanoparticle measuring apparatus using the mobility deviation analyzer and the nanoparticle generating apparatus according to the present invention, it is possible to easily monitor whether the ultra fine dust measuring apparatus is in normal operation or not, It is possible to precisely calibrate the nanoparticle measuring device by itself. Therefore, the reliability of the measurement result can be improved, and the equipment cost can be greatly reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall configuration diagram showing a mobility deviation analyzer according to the present invention;
FIG. 2 is a view showing a flow of particles and a protective gas inside a mobility error analyzer according to a preferred embodiment of the present invention; FIG.
FIG. 3 is a view showing a flow of particles and a protective gas inside the mobility deviation analyzer according to another preferred embodiment of the present invention, FIG.
FIG. 4 is a general view showing a calibration system of a nanoparticle measuring apparatus to which a mobility deviation analyzer and a nanoparticle generating apparatus according to the present invention are applied.
5 is a cross-sectional view of a nanoparticle generating apparatus applied to a calibration system of a nanoparticle measuring apparatus according to an embodiment of the present invention,
FIG. 6 is a perspective sectional view of the nanoparticle generating apparatus of FIG. 5,
7 is a perspective sectional view of a nanoparticle generating apparatus applied to a calibration system of a nanoparticle measuring apparatus according to another embodiment of the present invention,
8 is a graph comparing the distribution of monodisperse nanoparticles classified by the mobility deviation analyzer according to the present invention and the mobility deviation analyzer of the prior art,
9 is a graph showing the relationship between particle diameters of the monodisperse nanoparticles to be classified and the operating voltage of the mobility deviation analyzer,
10 is a diagram showing a configuration diagram of a mobility deviation analyzer of the prior art.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a mobility error analyzer according to the present invention; FIG. 1, in the mobility deviation analyzer according to the present invention, a gas containing an aerosol, which is charged polydisperse particles, and a protective gas are supplied into the outer cylinder 20, and then the outer cylinder 20 And the internal electrode 30a from the upstream side in the longitudinal direction of the outer cylinder 20 toward the downstream side. If the electric field is formed between the inner electrode 30a and the inner wall 20a of the outer cylinder 20 by using the high voltage application unit 50, the charged polydisperse nanoparticles are attracted toward the inner electrode 30a by an electric field It gradually moves. Therefore, according to the electric mobility of the nanoparticles, the nanoparticles having a particle size of a specific size are discharged through the monodisperse nanoparticle outlet 70a of the outer cylinder 20, whereby the monodisperse nanoparticles having a desired particle diameter Classification.

The aerosols, which are charged polydisperse nanoparticles, are generated by the nanoparticle generating device and fed into the interior through the upper inlet end of the mobility deviation analyzer. More preferably, the particles are passed through a particle neutralizer (10) using a radioactive element, and the amount of charge of the nanoparticles is controlled to be constant and then supplied to a mobility deviation analyzer. However, as will be described later, when the nanoparticle generator of the present invention shown in FIGS. 5 to 7 is used, the generated nanoparticles are directly supplied to the mobility deviation analyzer without using the particle neutralizer 10 Is more preferable.

 The protective gas is sucked by the pump member 40c, filtered through the HEPA filter 40b, and then supplied to the inside through the air supply line from the top of the mobility deviation analyzer. Preferably, a flow control valve 40a is provided on the air supply line to control the flow rate of the protective gas supplied to the inside of the mobility deviation analyzer.

The mixed gas of the protective gas and the gas including the aerosol is discharged to the outside through the protective gas outlet port 70b at the lower end of the mobility deviation analyzer. At this time, as shown in FIG. 1, the HEPA filter 40b ), And then supplied to the inside of the mobility deviation analyzer again.

Preferably, the mobility deviation analyzer comprises a double cylindrical structure in which a cylindrical inner electrode coaxial with the outer cylinder is provided in a cylindrical outer cylinder. An inner space extending in the longitudinal direction of the outer cylinder 20 is formed between the inner wall 20a surface of the outer cylinder 20 and the outer circumferential surface of the inner electrode 30a and from the upper end to the lower end of the mobility deviation analyzer The mixed gas of the aerosol and the protective gas of the supplied polydisperse particles moves.

The introduced protective gas is supplied along the inner space at a constant flow rate (Qsh). Preferably, a laminar flow forming filter for forming the flow of the protective gas into a laminar flow may be provided inside the mobility deviation analyzer. The aerosol as the charged polydisperse nanoparticles is formed on the inner wall 20a side of the outer cylinder 20 while moving to a predetermined flow rate Qae along the space formed inside the outer cylinder 20 on the outer side of the protective gas And flows into the space between the inner wall 20a of the outer cylinder 20 and the inner electrode 30a through the dispersed particle inlet 60. [ The aerosol, the polydisperse nanoparticles, is mixed with the protective gas to form a mixed gas.

When the mixed gas containing the polydisperse nanoparticles is moved from the upstream to the downstream of the inside of the mobility deviation analyzer, the high voltage applying unit 50 applies the high voltage to the internal electrode 30a, Thereby forming an electric field between the inner wall 20a of the outer cylinder 20. The positively charged particles move toward the internal electrode 30a gradually by an electric field while moving downstream by a uniform flow field. That is, due to the flow of the mixed gas, during the time when the nanoparticles move from the inlet to the monodisperse nanoparticle outlet 70a at the same flow rate as the flow, the charged nanoparticles are electrically attracted toward the internal electrode 20a, And the drag speed is balanced with the end speed. At this time, the degree of acceleration of the charged nanoparticles toward the internal electrode 20a by the same charge amount depends on the particle diameter of the nanoparticles. That is, the degree of movement toward the internal electrode 30a varies depending on the particle diameter of the nanoparticles, and thus it becomes possible to classify the nanoparticles having a specific particle diameter.

However, as the particle size is reduced to a nanometer size, the classification performance is remarkably deteriorated due to the particle loss due to the brown diffusion, particularly at particle diameters of 50 nm or less. Particularly, as the gap between the electrodes (here, the gap between the inner electrode 30a and the inner wall 20a of the outer cylinder 20) becomes smaller, there is a higher possibility of occurrence of sparks due to insulation breakdown of air, In the deviation analyzer, the gap between the electrodes is maintained at least 10 mm. In this case, when the nanoparticles of the same size are classified, there arises a problem that the error due to brown diffusion becomes larger. In this case, since the gap between the electrodes must be maintained at about 10 mm, a relatively high electric field must be applied. In order to reduce the residence time, it is necessary to use a high-flow-rate protective air. Therefore, there is a problem that a high-flow pump and a HEPA filter having a large process flow rate must be used.

Therefore, the inventor of the present invention has made the inner electrode 30a or the surface of the inner wall 20a of the outer cylinder 20 to be an insulator electrode including the insulator 30b. In this case, even if a high voltage is applied to the inner electrode 30a, the potential applied to the surface of the insulator electrode can be maintained at the same level as the input potential, while a current is prevented from flowing to the surface of the insulator, Can be suppressed.

Therefore, when the insulator electrode is used, the occurrence of local spark discharge can be suppressed even if the distance between the electrodes is reduced to 10 mm or less, so that the distance between the electrodes can be reduced compared with the conventional one. If the distance between the electrodes is reduced from 10 mm to 5 mm conventionally, the length of the device can be reduced to about 1/4 under the condition of the same applied voltage. Then, under the same condition, the moving distance of the nanoparticles is reduced to about 1/2, so that the lowering of the classification efficiency due to the brown diffusion can be suppressed. Further, the capacity of the HEPA filter 40b and the capacity of the pump member 40c can be reduced, because the capacity of the high voltage supply apparatus, which has conventionally required an operating voltage of about 10 kV, can be reduced to about 5 kV or less and the apparatus can be driven at a low flow rate. . As a result, it is possible to miniaturize the entire apparatus and parts.

The insulator electrode having the insulator 30b may be formed by applying an insulating material to the surface of the electrode or fixing the insulator 30b to the surface of the electrode. As the material of the insulator 13, glass, rubber, marble, mica, polystyrol, polyethylene teflon, oxidative ceramics, or a mixture thereof may be used. In order to suppress the occurrence of sparks, it is preferable that the insulator 30b is formed on at least one of the opposing electrodes, at least on the surface facing the other electrode.

In the embodiment shown in FIG. 1, the two electrodes are composed of the cylindrical inner electrode 30a and the inner wall 20b of the cylindrical outer cylinder 20 surrounding the cylindrical inner electrode 30a. However, the present invention is not limited to this, And the case where the two disk-shaped electrodes form a Viennese, if possible.

FIG. 2 is a view showing a flow of particles and a protective gas inside the mobility deviation analyzer according to a preferred embodiment of the present invention shown in FIG. 1. FIG.

In the embodiment shown in Fig. 2 (a), the internal electrode 30a is an insulator electrode formed of a cylindrical hollow member and the insulator 30b is provided on the surface of the internal electrode 30a. The polydisperse particle inlet 60 in which the charged polydisperse particles are introduced into the inner wall 20a of the outer cylinder 20 in the embodiment of Fig. 2 (a) is located on the upstream side of the flow path of the protective gas, (20a) of the outer cylinder (20). The outlet 70a of the monodisperse particle, which is the target of the classification, is formed by slanting the wall portion of the internal electrode 30a at the downstream side of the flow passage. Therefore, the aerosol, which is the polydisperse particle introduced into the flow rate Qae through the polydisperse particle inlet 60, is mixed with the protective gas flowing at the flow rate of Qsh, and is moved to the downstream side. At this time, due to the electric field formed between the inner electrode 30a and the inner wall 20a of the outer cylinder 20, among the charged polydisperse particles, particles having a size of a predetermined electric mobility are separated from the outlet 70a of the monodisperse particle, And passes through the outlet 70a of the monodisperse particle, flows into the hollow space inside the internal electrode 30a, and is classified with other particles.

2B is different from FIG. 2A in that an insulator 20b is provided on the surface of the inner wall 20a of the outer cylinder 20, not the inner electrode 30a, to form an insulator electrode. The insulator may be formed on either one of the two electrodes or on both electrode surfaces.

3 is a view showing another preferred embodiment related to the flow of particles and protective gas inside the mobility deviation analyzer of the present invention shown in Fig.

In the embodiment shown in FIG. 3A, the internal electrode 30a is formed of a cylindrical hollow member as shown in FIG. 2 (a), and the surface of the internal electrode 30a is provided with an insulator 30b Is an insulator electrode. 3 (a), the protective gas flows from the front end and the rear end of the outer cylinder 20 in the longitudinal direction to the inside of the outer cylinder 20 ≪ / RTI > The polydisperse particle inlet 60 into which the charged polydisperse particles are introduced into the outer cylinder 20 flows from the upstream side and the downstream side of the protective gas flow path to the outer cylinder 20 in the direction in which the protective gas flows, Is formed by slanting through the wall portion 20a. The classified monodisperse particle outlet 70a is formed by slanting the wall portion of the internal electrode 30a between the two polydisperse particle inlets 60 in the longitudinal direction of the external cylinder 20.

Therefore, the charged polydisperse particles introduced from the polydisperse particle inlet 60 in the vicinity of the upper and lower ends of the outer cylinder 20 are moved to the vicinity of the longitudinal center of the outer cylinder 20. [ Due to the electric field formed between the inner electrode 30a and the inner wall 20a of the outer cylinder 20, among the charged polydisperse particles, particles having a size of a predetermined electric mobility have two opposing monodisperse particles Reaches the outlet 70a, passes through the outlet 70a of the monodisperse particle, flows into the hollow space inside the internal electrode 30a, and is classified with other particles.

The mixed gas containing the protective gas and the undifferentiated nanoparticles is discharged from the outlet formed through the outer cylinder 20 near the longitudinal center of the outer cylinder 20 to the flow rate Qexc.

3B is different from FIG. 3A in that the insulator 20b is provided on the surface of the inner wall 20a of the outer cylinder 20, not the inner electrode 30a, to form an insulator electrode. The insulator may be formed on either one of the two electrodes or on both electrode surfaces.

8 is a graph showing a transfer function which is an index for evaluating the performance of the mobility deviation analyzer. 7 shows the ratio (Zp / Zp ^* ) of the electric mobility (Zp) of the nanoparticles classified by the mobility deviation analyzer to the electric mobility (Zp ^* ) of standard nanoparticles having a target particle diameter, And the Y axis is the ratio of the concentration of the nanoparticles classified by the mobility deviation analyzer to the coefficient concentration of the standard nanoparticles.

8, in the case of using the mobility deviation analyzer according to the present invention in which the interval between the electrodes is reduced from 10 mm to 5 mm by using the insulator electrode in comparison with the mobility deviation analyzer using the conventional general electrode, It can be seen that it is much improved.

9 is a graph showing the relationship between particle diameters of monodisperse nanoparticles to be classified and the operating voltage of the mobility deviation analyzer. Specifically, FIG. 9 shows the operating voltage required for classifying nanoparticles having a desired particle diameter Dp in the mobility error analyzer according to the present invention, in which the inter-electrode gap is 5 mm. According to the contents of FIG. 9, it can be seen that the nanoparticles of 30 nm in size can be classified by applying an operating voltage of about 3.5 kV to the electrodes. In order to classify nanoparticles of the same size, considering the limitations of the prior art in which the operating voltage was applied at about 7 kV under the condition that the gap between the electrodes was about 10 mm, in the mobility deviation analyzer according to the present invention, 1/2, while the operating voltage can be reduced to about 1/2.

FIG. 4 is an overall schematic view showing a calibration system of a nanoparticle measuring apparatus to which a mobility deviation analyzer and a nanoparticle generating apparatus according to the present invention are applied. As shown in FIG. 4, the calibration system of the nanoparticle measuring apparatus according to the present invention is a nanoparticle generating apparatus for generating charged polydisperse nanoparticles. And a mobility deviation analyzer for primarily classifying the polydisperse particles generated by the nanoparticle generating device into mono-dispersed particles having a desired particle size by an electric field and a calibrating nanoparticle measuring device.

As shown in FIG. 4, the mobility deviation analyzer of the calibration system of the nanoparticle measuring apparatus according to the present invention has the same configuration as the mobility deviation analyzer according to the present invention shown in FIG. Therefore, redundant description with respect to the mobility deviation analyzer will be omitted. The apparatus for generating nanoparticles of the calibration system of the nanoparticle measuring apparatus according to the present invention will be described later with reference to FIG. 4 to FIG.

The charged polydisperse nanoparticles generated in the nanoparticle generating device are supplied to the mobility deviation analyzer from the nanoparticle generator outlet 500 through a feed line. As described with reference to Fig. 1, in the mobility deviation analyzer, monodisperse nanoparticles having a particle size targeted for charged polydisperse nanoparticles in an electric field are classified.

For example, it is necessary to generate monodisperse standard particles having the same size in real time in order to judge whether the nanoparticle measuring apparatus such as an ultrafine dust measuring apparatus is normally operated and further perform accurate calibration. In the calibration system of the nanoparticle measuring apparatus according to the present invention, high concentration non-cohesive polydisperse nanoparticles can be generated with low energy using a nanoparticle generating apparatus as described later, The monodisperse nanoparticles of the same size desired can be efficiently classified and supplied.

Accordingly, when the classified monodisperse nanoparticles are supplied to the nanoparticle measuring device to be calibrated and the measurement is performed, it is possible to judge whether or not the measuring device is abnormal, and calibration of the measuring device can be performed based on this.

More specifically, as shown in FIG. 4, the monodisperse nanoparticles, which are first classified in the mobility deviation analyzer, are discharged through the monodisperse nanoparticle outlet 70a and are aligned along the feed line to the nanoparticle measuring device 600 . The nanoparticle measuring device 600 is a device for measuring and analyzing the size and concentration of supplied particles.

In the calibration system of the nanoparticle measuring apparatus according to the present invention, monodisperse particles having a target particle size can be efficiently generated in real time, and the generated monodispersed particles can be measured by the nanoparticle measuring apparatus 600 to be calibrated , It is possible to determine whether the nanoparticle measuring device 600 is operating normally. In addition, the device can be calibrated using the measurement result of the nanoparticle measuring device 600. [

Here, the nanoparticle measuring device 600 to be calibrated may include a device capable of measuring the size of ultrafine nanoparticles such as DMAS (Differential Mobility Analysis System), SMPS (Scanning Mobility Particle Sizer), and Nono Scan have.

 In order to determine whether or not the measuring apparatus is in normal operation, the nanoparticle measuring apparatus 600 forms an electric field inside the nanoparticle measuring apparatus 600 so as to correspond to the electric mobility of the monodisperse particles during the first classifying. Therefore, ideally, the peak of the curve of the electric mobility and the coefficient concentration of the monodispersed nanoparticles at the first classification and the peak point of the curve of the coefficient of concentration and the electric mobility of the monodisperse particle at the secondary classification should be close to each other do. Accordingly, it is possible to judge whether or not the second classifier of the nanoparticle measuring apparatus 600 that performs the second class classification is abnormal, by comparing the graph related to the above transfer function, and it is possible to calibrate the abnormality .

FIG. 5 and FIG. 6 are views showing a nanoparticle generating apparatus applied to the calibration system of the nanoparticle measuring apparatus shown in FIG. Specifically, FIG. 5 is a cross-sectional view of the nanoparticle generator of the first embodiment of the present invention shown in FIG. 4, and FIG. 6 is a perspective view of the nanoparticle generator of FIG.

As shown in FIGS. 4, 5 and 6, the nanoparticle generating apparatus applied to the calibration system of the nanoparticle measuring apparatus of the present invention includes a local heating apparatus (not shown) (210) is inserted into the inner space from one side of the main body (100), and a local heating device (210) is inserted in the main body (100) so that the local heating device A first inlet 300 provided at one side of the main body 100 for introducing outside air into the inside of the insulating tube 200 and a second inlet 300 provided at a side of the main body 100 for introducing outside air into the space between the insulating tube 200 and the main body 100 A second inlet 400 provided at one side of the main body 100 and a second inlet 400 provided at the other side of the main body 100 for discharging the air introduced into the main body 100 through the heat insulating tube 200 to the outside of the main body 100 And a nanoparticle generating device outlet (500).

A uniform air distribution unit 310 for uniformly guiding the flow of outside air introduced into the main body 100 through the first inlet 300 is provided at one side of the heat insulating tube 200. In the mixed air uniform distribution part 310, upper and lower holes are formed so that the outside air is guided upward and downward around the local heating device 210.

Shaped dilution between the heat insulating tube 200 and the main body 100 in order to uniformly guide the flow of the external air flowing into the main body 100 through the second inlet 400 to the end of the heat insulating tube 200, An air uniform distribution portion 410 is provided. The dilution air uniform distribution portion 410 is perforated at regular intervals to form an annular shape.

The length L1 of the local heating device 210 may be equal to the length L2 of the heat insulating tube 200, or may be slightly longer or shorter (see FIG. 4).

The heat insulating tube 200 has a structure capable of effectively shielding radiant heat generated at the surface of the high-temperature local heating apparatus 210, and has a structure capable of covering all or a part of the upper and lower portions of the high- .

Also, the local heating device 210 may be formed in a columnar shape.

The first embodiment of the present invention further includes a gas supply source connected to the first inlet 300 and the second inlet 400 and the gas supply source may be connected to the first inlet 300 or the second inlet 400, And an apparatus for controlling the amount of air is provided. 4, the gas supply for introducing the outside air into the first inlet 300 or the second inlet 400 is preferably provided with pump members 300c and 400c for sucking outside air, HEPA filters 300b and 400b for filtering the air, and flow rate supply valves 300a and 400a for adjusting the supply flow rate.

 The nanoparticle generator outlet 500 is formed in the body 100 so as to face the direction of gravity.

The inlet of the external air to the main body 100 includes a first inlet 300 connected to the insulating tube 200 to pass through the local heating device 210 for heating the sample to generate nanoparticles, 100 into a second inlet 400 connected by a flow path of a diluent gas.

The flow of the generated nanoparticles and the flow of the diluting gas are mixed with each other at the end of the insulation tube, and the gas containing the diluted nanoparticles is delivered to the desired target object through the nanoparticle generator outlet 500.

When the external air is supplied to the first inlet 300 and the second inlet 400 using a single device and the pressure difference between the external air and the external air is generated, The flow rate of the external air flowing into the flow path 400 may be different.

The heat insulating tube 200 absorbs radiant energy generated from the surface of the heating unit of 1500 degrees or more and prevents the heat from being transmitted to the main body 100, thereby preventing the temperature of the main body 100 from being excessively increased. Thus, the size of the main body 100 can be reduced.

Also, it is possible to realize a condition that the gas flow pattern inside the heat insulating tube 200, that is, the vicinity of the local heating apparatus 210, which is a space where nanoparticles are generated, can be kept constant, The flow rate of the diluent gas introduced between the tube 200 and the main body 100 can be changed, so that the concentration of the generated nanoparticles can be controlled.

In order to increase the condensation time of the gasified sample, it is necessary to increase the length of the heat insulator tube, shorten the condensation time of the gasified sample, and reduce the basic particle size of the nanoparticle, The length of the tube 200 can be shortened and used.

7 is a cross-sectional view of the nanoparticle generating apparatus of the second embodiment applied to the calibration system of the nanoparticle measuring apparatus of the present invention. 7, the length L1 of the local heating device 210, the length L2 of the heat insulating tube 200, the length L3 of the main body 100, and the axial length L4 of the heat- .

As shown in FIG. 7, the nanoparticle generating apparatus of the second embodiment is characterized in that the body 100 has a heat spread window 120.

The heat exiting window 120 is formed at a position adjacent to the other end of the heat insulating tube 200 and is formed in an annular shape along the body 100. More precisely, the heat emission window 120 is positioned so that the end of the heat insulating tube 200 and the local heating apparatus 210 are positioned within the axial length L4 of the heat radiation window 120. [

In addition, the thermotropic window 120 is formed of a transparent material such as quartz or tempered glass.

As described above, the nanoparticle generating apparatus according to the second embodiment is characterized in that a part of the main body 100 is formed of a transparent material such as quartz or tempered glass.

By making the length of the heat insulating tube 200 approximately equal to or shorter than the length of the local heating device, even if the radiant energy is partially transmitted to the main body 100, the radiant energy can be transmitted to the outside through the transparent window, The temperature of the gas containing the nanoparticles is relatively lowered.

In addition, since it is possible to visually check whether the reaction in the apparatus is proceeding incidentally, it is possible to promptly respond to a problem.

Since the nanoparticles produced at the same time are mixed with the diluted air at a high speed, the concentration of the generated high concentration nanoparticles is instantaneously lowered, and the aggregation can be suppressed as much as possible.

The nanoparticle generating apparatus of the third embodiment is characterized in that the length of the heat insulating tube 200 is longer than the length of the local heating apparatus 210.

In the nanoparticle generating apparatus according to the third embodiment, the length of the heat insulating tube 200 is longer than the length of the local heating apparatus 210, so that the radiant energy is transmitted to the ceramic tube, Is minimized.

Since dilution air passing through the exterior of the adiabatic tube 200 is mixed with air containing nanoparticles passing therethrough, heat transfer through contact or radiation with the surface with the localized heating device 210 is minimized, The aerosol particles can be supplied, and the concentration change can be easily controlled according to the dilution ratio.

Adjusting the length of the heat insulating tube 200 inserted into the main body 100 can control the residence time at a high concentration before the generated nanoparticles meet the diluted air, The shape of the nanoparticles can be controlled.

The nano particle generating apparatus of the fourth embodiment is characterized in that the local heating apparatus 210 is provided with an ion generating apparatus.

The ion generating device is mounted on the local heating device 210 and positioned closer to the first inlet 300 than the sample applied to the local heating device 210 for gasification through the local heating device 210.

The nanoparticle generating apparatus according to the fourth embodiment has a structure in which a large amount of ions are generated before the point at which the nanoparticles are generated, so that the nanoparticles can be charged to a high degree with a single polarity in the process of generating nanoparticles.

Nanoparticles smaller than 10 nanometers are mostly neutral, so it is not easy to separate them from the gas flow.

If the particles are charged, they can be easily separated from the gas flow if they are present in the electric field, so that they can be used in various applications.

In the case of the above-described nanoparticle generating device, the nanoparticles are positively charged at a rate higher than the Boltzmann distribution in the production process. In the case of such a nanoparticle generating apparatus, unlike the electrostatic spraying method or the spark generating apparatus, which is a conventional technique for generating nanoparticles, it is possible to prevent particles from being charged higher than necessary in the process of generating nanoparticles. Therefore, when the produced nanoparticles are supplied to the mobility deviation analyzer, it is not necessary to pass the generated nanoparticles through a neutralization apparatus using a radioactive substance as in the conventional method. Therefore, when the above-described nanoparticle generating apparatus is applied to a calibration system of a nanoparticle measuring apparatus, a system can be constructed more easily.

According to the calibration system of the nanoparticle measuring apparatus according to the present invention, it is possible to determine whether there is an abnormality in real time when an abnormality occurs in the nanoparticle measuring apparatus as in the prior art, and to send the measurement apparatus to the manufacturer , It is possible to calibrate the apparatus itself, thereby improving the reliability of the measurement result, and significantly reducing the equipment cost.

10: Particle thickener 20: Outer cylinder
20a: outer cylinder inner wall 20b: insulator
30a: internal electrode 30b: insulator
40a: Flow control valve 40b: HEPA filter
40c: Pump member 60: Polydisperse particle inlet
70a: monodisperse nanoparticle outlet 70b: protective gas outlet
100: main body 110: electric insulator
120: Heat Exchanger 200: Heat Insulating Tube
210: local heating device 300: first inlet
310: Mixed-air uniform distribution part 400: Second inlet
410: Dilution air uniform distribution part 500: Nano particle generation device outlet
600: Nano particle measuring device

Claims (22)

A flow path of a mixture of an aerosol and a protective gas, which is charged polydisperse particles, is provided between opposing electrodes, and by using an electric field formed between the opposing electrodes, the electric mobility of the charged polydisperse particles is used, A differential mobility analyzer for classifying the polydisperse particles into mono-dispersed particles having a desired particle size,
Wherein at least one of the electrodes facing each other is made of an insulator at least on a surface facing the other electrode. The method according to claim 1,
Wherein the mobility error analyzer comprises:
An aerosol containing the charged polydisperse particles and an outer cylinder into which the protective gas flows, a gas mixture of the aerosol and the protective gas, which extends in the longitudinal direction of the outer cylinder, An inner electrode forming the electric field, and a monodisperse particle outlet through which the monodisperse particles are discharged from the flow path. The method of claim 2,
Wherein the insulator is formed on at least one surface of the outer cylinder or the inner electrode. The method of claim 2,
Wherein the outer cylinder and the inner electrode are cylindrical hollow members extending in the longitudinal direction. The method of claim 4,
Wherein the polydisperse particle inlet into which the charged polydisperse particles are introduced into the cylinder is formed so as to penetrate through the wall portion of the outer cylinder at an upstream side of the flow path,
Wherein the monodisperse particle outlet is formed so as to pass through the wall portion of the internal electrode obliquely on the downstream side of the flow path. The method of claim 4,
The protective gas flows into the outer cylinder at the front end and the rear end of the outer cylinder in the longitudinal direction,
The polydisperse particle inlet into which the charged polydisperse particles are introduced into the outer cylinder is formed so as to penetrate the wall portion of the outer cylinder obliquely in the direction in which the protective gas flows in the upstream side and the downstream side of the flow path ,
Wherein the monodisperse particle outlet is formed by slanting the wall portion of the inner electrode between the two polydisperse particle inlets in the longitudinal direction of the outer cylinder. The method according to claim 1,
And the distance between the opposing electrodes is 2 mm to 8 mm. A nanoparticle generator for producing charged polydisperse nanoparticles.
Wherein a flow path of a mixture of an aerosol and a protective gas, which is the charged polydisperse particles generated by the nanoparticle generating device, is provided between opposing electrodes, and the electric field formed between the opposing electrodes A mobility deviation analyzer for primarily classifying the polydisperse particles into monodisperse particles having a desired particle size using the electric mobility of the dispersed particles,
A calibration target nanoparticle measuring device for measuring monodispersed particles generated from the mobility deviation analyzer,
Wherein at least one of the opposed electrodes of the mobility deviation analyzer is composed of an insulator at least on the surface facing the other electrode. The method of claim 8,
Wherein the nanoparticle generating device comprises:
A body which forms an internal space and into which the local heating device with an electric insulator is inserted from one side into the internal space;
A heat insulating tube inserted into the body and to which the local heating device is inserted so that the local heating device is located along the central axis;
A first inlet provided in the main body for introducing outside air into the heat insulating tube;
A second inlet provided in the main body for introducing outside air into the space between the heat insulating tube and the main body;
And a nanoparticle generating device outlet provided in the main body for discharging the air introduced into the main body through the heat insulating tube to the outside of the main body. The method of claim 9,
And a mixed air uniform distribution unit for uniformly guiding the flow of external air introduced into the body through the first inlet to the heat insulating tube. The method of claim 10,
Wherein the mixed air uniform distribution portion is formed with an upper hole and a lower hole so that external air is directed upward and downward around the local heating device. The method of claim 9,
And a ring-shaped dilution air uniform distribution unit is provided between the heat insulating tube and the main body so as to uniformly guide the flow of the external air introduced into the main body to the end of the heat insulating tube through the second inlet. Calibration system of nanoparticle measuring device. The method of claim 12,
Wherein the dilution air uniform distribution unit is perforated at regular intervals to form an annular shape. The method of claim 9,
Wherein the length of the local heating device is equal to or shorter than the length of the heat insulating tube. The method of claim 9,
Wherein the body is provided with a heat release window in an annular shape along the body. 16. The method of claim 15,
And an end portion of the heat insulating tube and the local heating device are positioned within an axial length of the heat release window. 16. The method of claim 15,
Wherein the heat dissipation window is formed of a transparent material such as quartz or tempered glass. The method of claim 9,
Wherein the local heating device has a cylindrical shape. The method of claim 9,
Wherein the local heating apparatus is provided with an ion generating device. The method of claim 19,
Wherein the ion generating device is disposed in the local heating device,
Wherein the sample is located closer to the first inlet than to the sample applied to the local heating device for gasification through the local heating device. The method of claim 9,
And a device for adjusting the amount of external air introduced into the first inlet or the second inlet. The method of claim 9,
Wherein the outlet of the nanoparticle generator is formed in the body so as to face the direction of gravity.

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