Dielectric powder sorting equipment

Abstract

The present invention discloses a dielectric powder sorting device, which includes a chamber, a lower electrode in the chamber, and an upper electrode disposed at an upper end of the chamber and spaced apart from the lower electrode, and when a dielectric powder is placed on the lower electrode and an AC electric field is applied, the dielectric powder is charged and an upward flow is induced to sort the dielectric powder, and the voltage and frequency are controlled to control the dielectric powder according to particle size, weight, density, dielectric constant, or surface area.

Description

[Technical field]

[0001] The present invention relates to a dielectric powder sorting device that can easily sort dielectric powder by particle size, weight, density, dielectric constant, or surface area. [Background technology]

[0002] Powder sorting is widely used in the paint, pigment, ink, abrasive, and other industries. In general, powder sorting can sort powders by utilizing the difference in the magnitude of gravity and centrifugal or inertial forces acting according to the size and mass of the powder. In addition, powders can be sorted according to the direction of action and flow of an externally applied force. For example, when a downward flow of powder is induced from top to bottom in a chamber, if an air flow is applied in the middle in a direction perpendicular to the downward flow, heavy powders subjected to high gravity will sink, and light powders subjected to low gravity will be moved to another space by the air flow and sorted.

[0003] However, this method has the disadvantage that it takes a long time to classify the powder, and it is difficult to classify fine particles when they are very small. Therefore, the present invention provides an apparatus that can easily classify powder in a short time by using an AC electric field. Summary of the Invention [Problem to be solved by the invention]

[0004] The object of the present invention is to provide a dielectric powder sorting device that can easily sort mixed dielectric powders by particle size, type, and shape by using the force of q·E to make the charged dielectric powder flow in an AC electric field. [Means for solving the problem]

[0005] FIG. 1 is a diagram showing the structure of a dielectric powder sorting device according to the present invention.

[0006] Referring to FIG. 1, a dielectric powder sorting device A for the purpose of the present invention includes a chamber, a lower electrode in the chamber, an upper electrode spaced apart from the lower electrode in the chamber and disposed at an upper end, a first separation layer located between the upper electrode and the lower electrode in the chamber and not covering the upper electrode and the lower electrode entirely, and a power supply means for applying an AC power supply to the lower electrode and the upper electrode to apply an AC electric field between the lower electrode and the upper electrode, and is characterized in that a dielectric powder is positioned between the lower electrode and the first separation layer.

[0007] In the present invention, when an AC electric field is applied, a higher electric field is applied inside the dielectric powder layer than outside, and gas discharge occurs more easily to charge the dielectric powder particles. The charged dielectric powder particles may have a force that allows them to flow upward in the electric field in the chamber, and they can easily rise in the chamber. At this time, the force that allows the dielectric powder to flow upward may be applied differently depending on the size, density, shape, etc. As a result, the composition of the dielectric powder accumulated on the first separation layer and the lower electrode after the AC electric field is applied may differ. The present invention is characterized in that the dielectric powder is selected by utilizing this difference.

[0008] The upward flow of the dielectric powder can be controlled by controlling the magnitude of the voltage and the AC frequency applied to the dielectric powder sorting device of the present invention. Therefore, the dielectric powder can be easily sorted by particle size, weight, density, dielectric constant, surface area, etc., by the sorting device of the present invention. A detailed description of this will be given with reference to the following FIGS. 2 to 15 and examples.

[0009] In the present invention, the characteristics of plasma generation inside and outside the fluid powder bed can be controlled under voltage conditions provided by the gas supplied or supplied into the chamber when an AC electric field is applied. The gas supplied or supplied into the chamber when an AC electric field is applied may be air. In the case of flammable dielectric powder, a gas not containing oxygen may be used. In the present invention, the gas supplied or supplied into the chamber when an AC electric field is applied is not particularly limited in type.

[0010] In the present invention, the dielectric powder means an insulating powder that can be polarized positively and negatively in the direction of the electric field, and may be a material having a net charge by storing excess charges in the form of electrons (-) or holes (+) on the surface by the charging step described below (e.g., application of plasma by application of an electric field, photoelectric effect by irradiation of ultraviolet light, etc.). In one embodiment, the dielectric powder may be a charged dielectric powder. Compared with uncharged dielectric powder, charged dielectric powder can have a net charge on the surface (excessive charge stored in the powder other than the offset amount of positive-negative polarized charges), and therefore can more easily separate from the powder layer and have the ability to flow upward. Preferably, the dielectric powder may be a dielectric powder having a size of several nm to several thousand μm.

[0011] In one embodiment, a charging step of charging the dielectric powder in the chamber may be further performed before the generation of the AC electric field. For example, the charging step may be performed by applying an electric field for dielectrophoresis to the dielectric powder, irradiating the dielectric powder with UV light, or generating plasma.

[0012] In one embodiment, the charging step includes filling the chamber with a first gas, applying a voltage to generate plasma in the dielectric powder, and then filling the chamber with a second gas, the first gas being a gas having a lower discharge onset voltage than the second gas. For example, the charging step may be performed by filling the chamber with helium, applying a voltage to generate plasma in the dielectric powder to charge the dielectric powder, and then filling the chamber with air or SF6 having a higher discharge onset voltage than helium.

[0013] In the present invention, the upper and lower electrodes can alternately act as a power electrode and a ground electrode. For example, when the lower electrode is a power electrode, the upper electrode can be a ground electrode, and when the lower electrode is a ground electrode, the upper electrode can be a power electrode.

[0014] The dielectric powder sorting device B for the purpose of the present invention is characterized in that it further includes a second separation layer located between the upper electrode and the lower electrode in the chamber, having a different height from the first separation layer, and not covering the entire upper electrode and the lower electrode. When an AC electric field is applied to the dielectric powder sorting device B, the dielectric powder has different upward flow forces depending on its size, density, surface area, etc., and can be piled up on the first separation layer and the second separation layer according to the sorting criteria.

[0015] In the present invention, the first and second separating layers may be dielectric. The distance between the first and second separating layers and the distance between the second separating layer and the upper electrode can be easily adjusted by the user. If the distance between the lower electrode and the first and second separating layers is too long, a problem occurs in that a voltage higher than necessary must be applied. Therefore, the distance between the lower electrode and the first and second separating layers may be less than about 40 mm.

[0016] The dielectric powder sorting apparatus A and B of the present invention may further include a dielectric substrate laminated on the lower electrode. When a high voltage is applied between the upper and lower electrodes without a dielectric substrate, arc and spark discharges occur, making it difficult to apply the desired high electric field, and charged particles flow only by arc and spark discharges, making it difficult to impart a net charge to the powder particles. Therefore, the dielectric powder sorting apparatus of the present invention may preferably further include a dielectric substrate laminated on the lower electrode.

[0017] The dielectric powder sorting device C for the purpose of the present invention includes a chamber, a lower electrode in the chamber, an upper electrode disposed between an upper end of the chamber body and the lower electrode so that the chamber can be divided into an upper space and a lower space, the upper electrode not entirely covering the lower electrode, and a power supply applying means for applying an AC power supply to the lower electrode and the upper electrode so that an AC electric field is applied between the lower electrode and the upper electrode, and the dielectric powder is located between the lower electrode and the upper electrode.

[0018] The configuration of the dielectric powder sorting apparatus C is substantially the same as the configurations of the dielectric powder sorting apparatuses A and B described above with reference to FIG. 1, so a detailed description thereof will be omitted and differences will be mainly described below.

[0019] When an AC electric field is applied to the dielectric powder sorting device C, the dielectric powder accumulated on the upper electrode is no longer exposed to the electric field and does not flow, so it can be sorted according to the criteria, and in the case of powder that hits the lower surface of the upper electrode, it diffuses and distributes uniformly in the process of repeatedly rising and falling due to the AC electric field, and eventually accumulates on the upper electrode, so it can be sorted. In general, the frequency of the applied voltage is about several hundred Hz, so that the powder repeats rising and falling several hundred times per second, and the dielectric powder according to the sorting criteria accumulates on the upper electrode within a few seconds, so that the dielectric powder can be easily sorted within a short time.

[0020] The upper space formed in the chamber by the upper electrode can be any space having a distance that allows the powder to flow.

[0021] In the present invention, the dielectric powder sorting device C may further include a first dielectric substrate disposed above the upper electrode to form a space in which the powder can flow, and a second dielectric substrate stacked on the lower electrode. The first dielectric substrate prevents the rising powder from passing through the upper electrode and leaving the sorting device, and has the effect of isolating any gas in the sorting device from the outside air.

[0022] The apparatus may further comprise a dielectric substrate disposed on the upper end of the chamber and on the lower electrode together with the sorting devices A and B.

[0023] In the present invention, even if the dielectric powder flows upward and hits the upper end of the chamber and falls, it does not have a significant effect on the present invention as long as it falls onto the first separation layer, the second separation layer, and the upper electrode provided as a filtering means and is separated.

[0024] In the present invention, the feeding of the dielectric powder and the recovery after sorting may be carried out using means such as gas flow, mechanical vibration and paddles. Effect of the Invention

[0025] According to the present invention, by controlling the voltage and frequency in consideration of the characteristics of each dielectric powder particle, it is possible to sort the mixed dielectric powder according to particle size, weight, density, dielectric constant, or surface area within a few seconds to a few minutes. [Brief description of the drawings]

[0026] [Figure 1] 1 is a diagram showing the structure of a dielectric powder sorting device of the present invention. [Diagram 2] 2 is a diagram showing the principle of flow of dielectric powder through the dielectric powder screening device of the present invention. [Diagram 3]2 is a diagram illustrating an AC electric field applied through the dielectric powder sorting device of the present invention. [Figure 4] 4 is a diagram for explaining the behavior of dielectric powder that starts to flow in the dielectric powder sorting device of the present invention. [Diagram 5] 4 is a diagram for explaining the behavior of dielectric powder particles in an AC electric field in the dielectric powder sorting device of the present invention. [Figure 6] 2 is a diagram for explaining flow modes FF, TM, and LF of dielectric powder in the dielectric powder screening device of the present invention. [Figure 7] 2 is an image showing the flow modes FF, TM and LF of powder at high AC voltage through the dielectric powder separator of the present invention. [Figure 8] 1 is a diagram showing a dielectric powder sorting device used in Examples 1 to 3 of the present invention. [Figure 9] 1 shows an image of the dielectric powder used in Example 1 of the present invention. [Figure 10] 1 shows an image of the dielectric powder selected through Example 1 of the present invention. [Figure 11] 1 shows an image of the dielectric powder used in Example 2 of the present invention. [Figure 12] 1 shows an image of the dielectric powder selected through Example 2 of the present invention. [Figure 13] 1 shows an image of the dielectric powder selected through Example 2 of the present invention. [Figure 14] 1 shows an image of the dielectric powder selected through Example 3 of the present invention. [Figure 15] 1 shows an image of the dielectric powder selected through Example 3 of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, the embodiments of the present invention will be described in detail with reference to the attached drawings. The present invention can be modified in various ways and can have various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, but it should be understood that the present invention includes all modifications, equivalents, and alternatives within the spirit and technical scope of the present invention. In describing each drawing, like reference numerals are used for like components.

[0028] The terms used in this application are merely used to describe specific embodiments and are not intended to limit the present invention. A singular expression includes a plural expression unless the context clearly indicates otherwise. In this application, the terms "include" or "have" are intended to specify the presence of features, steps, operations, components, parts, or combinations thereof described in the specification, and should be understood not to preclude the presence or additional possibility of one or more other features, steps, operations, components, parts, or combinations thereof.

[0029] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the present invention pertains. Terms as defined in commonly used dictionaries should be interpreted to have a meaning consistent with the meaning they have in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense unless expressly defined in this application.

[0030] FIG. 2 is a diagram showing the principle of flow of dielectric powder using the dielectric powder screening device of the present invention.

[0031] Referring to FIG. 2, before the electric field is applied to the dielectric powder in the chamber, gravity F acts on the dielectric powder. g and the attractive force F between the dielectric powder d When an electric field is applied to the dielectric powder, the dielectric powder is subjected to the force of gravity F g and gravitational force F dThe electrostatic force F c At this time, the electrostatic force F applied to the dielectric powder is c is gravity F g and gravitational force F d If it is greater than the sum of (F c >F g +F d ), and the dielectric powder is subjected to electrostatic force F c This allows for upward flow.

[0032] The electrostatic force F c is the amount of charge q accumulated on the surface of the dielectric powder and the electric field E in the gas space above the dielectric powder layer. g It can be determined by (F c =q E g ), the attractive force F between the powder particles d is the electric field E applied in the dielectric powder layer p and is proportional to the dielectric constant ε of the dielectric powder (F d ∝E p , ε). At this time, the electric field E in the gas space above the dielectric powder layer is g and the electric field E applied in the dielectric powder layer p Since the magnitude of the voltage applied externally and the shape of the electrodes are determined, the present invention can easily select the dielectric powder by controlling the force applied to the dielectric powder by adjusting the magnitude of the voltage using a dielectric powder sorting device. In the present invention, factors that affect the flow of the dielectric powder other than the voltage include frequency and the amount of charge q accumulated on the surface of the dielectric powder.

[0033] In the present invention, the charge amount q accumulated on the surface of the dielectric powder is the most important factor that determines the flow characteristics of the dielectric powder. The charge amount q is most affected by the surface area (powder particle size and shape) and density / dielectric constant (type of powder) of the dielectric powder, and may also be affected by the type of surrounding gas. If the dielectric powder is light in weight and has a large surface area, it can flow very quickly in an external electric field, and if it is heavy in weight and has a small surface area, it can flow slowly in an external electric field. In addition, for dielectric powders of the same weight, the closer to a sphere (the smaller the surface area), the slower it can flow, and the more the shape is different from a sphere (the larger the surface area, for example, a plate-like, rod-like, cylindrical, etc. shape), the faster it can flow. In the present invention, the charge amount difference of such dielectric powders can be used to select them according to particle size, shape, density, and dielectric constant.

[0034] FIG. 3 is a diagram for explaining voltages applied through the dielectric powder separation device of the present invention.

[0035] Referring to FIG. 3, the voltage applied to the dielectric powder sorting apparatus of the present invention may be one AC high voltage selected from a sine wave, a square wave, a pulse wave, a triangular wave, a sawtooth wave, and the like. Preferably, the voltage may be a square wave. The square wave voltage has a square waveform, and a state in which the waveform changes once and returns to the initial state can be defined as one cycle. The time required to complete one cycle can be defined as a period T, and the number of cycles contained in one second can be defined as a frequency f.

[0036] In the dielectric powder sorting device of the present invention, the applied voltage V m is the voltage drop in the gas space, V g , the voltage drop across the dielectric powder layer V p , the voltage drop across the dielectric substrate V d It can be determined by the sum of (V m =V g +V p +2V d ), where the voltage drop in the gas space is V g and the voltage drop V across the dielectric powder layer pare the electric field E in the gas space, respectively. g and the electric field E applied in the dielectric powder layer p Each electric field affects the upward flow of the dielectric powder, so that when a high voltage is applied, the upward flow distance of the dielectric powder can be increased.

[0037] FIG. 4 is a diagram for explaining the behavior of dielectric powder that starts to flow in the dielectric powder sorting device of the present invention.

[0038] 4, when an AC electric field is applied in the chamber of the sorting apparatus of the present invention, a higher electric field can be applied inside the dielectric powder layer than outside the dielectric powder layer (i.e., the gas space in which the dielectric powder can flow upward). As a result, the dielectric powder particles are provided with a charge amount q on their surfaces, and an electrostatic force F that enables the upward flow is applied. c increases. High electrostatic force F c The dielectric powder particles separated from the dielectric powder layer by the attractive force F between the dielectric powder particles d Electrostatic force F excluding c and gravity F g The dielectric powder is then only affected by the force F net can be expressed as the following mathematical formula 1.

[0039]

number

[0040] Referring to Equation 1, the force F that causes the dielectric powder separated from the dielectric powder layer to flow upward is net The acceleration a of a dielectric powder particle rising in an electric field can be derived as follows:

[0041] At this time, the distance between the top of the dielectric powder layer and the bottom of the dielectric substrate, i.e., the maximum distance that the dielectric powder can move in the chamber, is d g If we define acceleration a and spatial distance d as g Through this, the dielectric powder is spaced apart by the following equation 2:g The time T when moving g can be derived.

[0042]

Number

[0043] In the present invention, when the dielectric powder moves a spatial distance d g The time T when moving g is less than T / 2 of the half cycle of the voltage, the dielectric powder hits the lower part of the dielectric substrate during the half cycle T / 2 and then falls back in the direction of the dielectric powder layer again. In the present invention, by utilizing such a technical principle, a first separation layer and a second separation layer are provided at appropriate positions between the upper electrode and the lower electrode in the chamber to select the dielectric powder, which is characterized by this.

[0044] FIG. 5 is a drawing for explaining the behavior of dielectric powder particles in an alternating electric field in the dielectric powder sorting device of the present invention. (T / 2 < t g )

[0045] Referring to FIG. 5, when the time T when the dielectric powder moves a spatial distance d g is greater than T / 2 of the half cycle of the voltage, in other words, when the spatial distance d g where the dielectric powder can flow is sufficiently long and the frequency of the voltage is high, the dielectric powder that has started to flow accelerates and rises by a distance d during the half cycle 0 to T / 2 of the voltage. When the polarity changes to the opposite, it decelerates and rises by a distance d' during the other half cycle T / 2 to T of the voltage. At this time, when the frequency condition of the voltage is d g < d + d', the dielectric powder will perform FF (Fully Fluidized) flow and reach the upper dielectric substrate completely. When d g = d + d', it will perform TM (Trap Mode) flow and almost touch the upper dielectric substrate. When d g > d + d', it will perform LF (Low Fluidized) flow. Such flow modes will be described with reference to FIG. 6. g > d + d', it will perform LF (Low Fluidized) flow. Such flow modes will be described with reference to FIG. 6.

[0046] FIG. 6 is a diagram for explaining flow modes FF, TM and LF of dielectric powder in the dielectric powder screening device of the present invention.

[0047] Referring to FIG. 6, the present invention can utilize the dielectric powder sorting apparatus to have three flow modes: FF, TM and LF. d+d' can be increased by increasing the external applied voltage and the surface area of ​​the dielectric powder particles, while d+d' can be decreased by increasing the frequency of the external applied voltage, the density of the powder particles and the dielectric constant. Therefore, d g By providing a filtering means such as a suitable first separation membrane and a second separation membrane at a position corresponding to the dielectric powder, and adjusting the magnitude of d+d' by controlling the magnitude and frequency of the externally applied voltage, the dielectric powder can be easily selected.

[0048] FIG. 7 is an image showing the flow modes FF, TM and LF of powder at high AC voltage through the dielectric powder separator of the present invention.

[0049] 7 shows images of FF, TM and LF modes performed through the dielectric powder sorting device of the present invention. In the FF mode, most of the dielectric powder flows upward from the lower electrode to the upper electrode, and in the TM mode, the lower electrode flows upward to a shorter distance than the upper electrode compared to the FF mode. On the other hand, in the LF mode, the dielectric powder flows upward a very short distance.

[0050] Hereinafter, the dielectric powder sorting apparatus of the present invention will be described in more detail with reference to specific examples and comparative examples. However, the examples of the present invention are merely some embodiments of the present invention, and the scope of the present invention is not limited to the following examples. [Embodiment]

[0051] [Experimental equipment]

[0052] FIG. 8 is a diagram showing a dielectric powder sorting device used in Examples 1 to 3 of the present invention.

[0053] 8, the dielectric powder sorting device has a structure including a lower electrode, an alumina substrate having a thickness of about 1 mm on the lower electrode, and an upper electrode (GND) disposed between the upper end of the chamber body and the alumina substrate. The dielectric powder was placed on the alumina substrate and the upper electrode to carry out the experiment.

[0054] [Experimental conditions]

[0055] The experimental conditions using the dielectric powder separator are shown in Table 1 below.

[0056] [Table 1]

[0057] Example 1

[0058] In Example 1 of the present invention, alumina ceramic powders for abrasives with different particle sizes were used. Specifically, a mixed powder of alumina ceramics (A100) having a size of 100 um and alumina ceramics (A10) having a size of 10 um was used, and the frequency was changed to 200 and 300 Hz at a voltage of 20 kVpp to perform particle size sorting of the dielectric powder.

[0059] FIG. 9 shows an image of the dielectric powder used in Example 1 of the present invention.

[0060] Referring to FIG. 9, it can be seen that the mixed powder used in Example 1 of the present invention is a homogeneous mixture of A100 and A10.

[0061] FIG. 10 shows an image of the dielectric powder selected according to Example 1 of the present invention.

[0062] Referring to Figure 10, when looking at the dielectric powder sorted under the conditions of 20kVpp and 200Hz frequency, it can be seen that the mixed powder with a high specific gravity of A10 is accumulated on the upper electrode, while the mixed powder with a high specific gravity of A100 is accumulated on the alumina substrate. It can be seen that under the conditions of 20kVpp and 200Hz frequency, A100 and A10 particles are not completely sorted. When looking at the dielectric powder sorted under the conditions of fixing the voltage magnitude and changing the frequency to 300Hz, it can be seen that only A10 powder is accumulated on the upper electrode.

[0063] The higher the frequency, the shorter the time it takes for powder particles to move upward or downward. When the same voltage is applied, when a low frequency (200Hz) is applied, the relatively immobile particles (heavy A100 with a small surface area to weight ratio) can also reach the separation layer, but when a high frequency (300Hz) is applied, only the relatively mobile particles (light A10 with a high surface area to weight ratio) can reach the separation layer and be separated. This shows that the dielectric powder sorting device of the present invention can be used to easily sort powders of the same type.

[0064] Example 2 - Dielectric powder separation according to frequency

[0065] In Example 2 of the present invention, a mixed powder of alumina ceramics (A100) having a size of 100 μm and alumina balls (AB100) having a size of 100 μm was used to select the dielectric powder at a voltage of 20 kVpp and a frequency of 100 to 500 Hz.

[0066] FIG. 11 shows an image of the dielectric powder used in Example 2 of the present invention.

[0067] Referring to FIG. 11, it can be seen that the mixed powder used in Example 2 of the present invention is a uniform mixture of A100 and AB100, and in the case of AB100, it can be seen that the powder is approximately rectangular, but has a larger deviation in particle size.

[0068] 12 and 13 show images of the dielectric powder selected according to Example 2 of the present invention.

[0069] 12 and 13, when the separation was performed under the conditions of 20 kVpp and a frequency of 100 to 500 Hz, looking at the dielectric powder P1 accumulated on the upper electrode, it was found that in the case of AB100, as the frequency decreased from 500 Hz to 100 Hz, particles with larger particle size accumulated, and in the case of A100, as the frequency decreased from 500 Hz to 100 Hz, particles with higher sphericity accumulated. After completing the separation experiment based on the frequency, looking at the powder P2 accumulated on the alumina substrate, it was found that AB100 powder with larger particle size accumulated.

[0070] This shows that the dielectric powder sorting device of the present invention can be used to easily sort mixed powders having different surface areas by controlling the frequency.

[0071] Example 3 - Dielectric powder separation according to voltage magnitude

[0072] In Example 3 of the present invention, the same mixed powder as that used in Example 2 was used to perform dielectric powder selection at a frequency of 200 Hz and a voltage varying in increments of 2 kVpp within the range of 14 to 24 kVpp.

[0073] 14 and 15 show images of the dielectric powder selected according to Example 3 of the present invention.

[0074] 14 and 15, when looking at the dielectric powder P1 accumulated on the upper electrode, it can be seen that as the magnitude of the applied voltage increases, A100 particles with relatively uniform shape and AB100 particles with larger particle size accumulate, and when looking at the powder P2 accumulated on the alumina substrate after completing the separation experiment based on the voltage magnitude, it can be seen that AB100 powder with larger particle size accumulates.

[0075] It can be seen that the dielectric powder sorting device of the present invention can be used to easily sort mixed powders having different surface areas by controlling the voltage.

[0076] Although the present invention has been described above with reference to a preferred embodiment, it should be understood that those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention as set forth in the claims.

Claims

1. A chamber; a bottom electrode within the chamber; an upper electrode disposed at an upper end of the chamber and spaced apart from the lower electrode; a first separation layer located within the chamber between the top electrode and the bottom electrode, the first separation layer not entirely covering the top electrode and the bottom electrode; and a power supply means for applying an AC power supply to the lower electrode and the upper electrode so that an AC electric field is applied between the lower electrode and the upper electrode; Including, a dielectric powder is disposed between the bottom electrode and the first isolation layer; Dielectric powder sorting equipment.

2. 2. The apparatus for separating dielectric powder according to claim 1, wherein the dielectric powder is a charged dielectric powder.

3. 2. The apparatus for separating dielectric powder according to claim 1, further comprising a step of additionally charging the dielectric powder prior to the generation of the alternating electric field.

4. The apparatus for separating dielectric powder according to claim 3 , wherein the charging step includes applying an electric field for dielectrophoresis to the dielectric powder, irradiating the dielectric powder with UV light, or generating plasma.

5. The charging step includes filling the chamber with a first gas, applying a voltage to generate a plasma in the dielectric powder, and then filling the chamber with a second gas; 4. The dielectric powder sorting device according to claim 3, wherein the first gas has a lower discharge start voltage than the second gas.

6. 2. The apparatus for sorting dielectric powder according to claim 1, wherein the dielectric powder is sorted according to particle size, weight, density, dielectric constant, or surface area.

7. 7. The apparatus for sorting dielectric powder according to claim 6, wherein the magnitude of the voltage and the AC frequency are controlled according to the sorting criterion.

8. 2. The dielectric powder sorting apparatus of claim 1, further comprising a second isolation layer located between the upper electrode and the lower electrode in the chamber, the second isolation layer having a different height than the first isolation layer and not covering the entire upper electrode and the lower electrode.

9. The dielectric powder sorting device according to claim 1 , further comprising a dielectric substrate laminated on the lower electrode.

10. A chamber; a bottom electrode within the chamber; an upper end electrode disposed between an upper end of the chamber body and the lower end electrode so that the chamber can be divided into an upper space and a lower space, the upper end electrode not entirely covering the lower end electrode; and a power supply means for applying an AC power supply to the lower electrode and the upper electrode so that an AC electric field is applied between the lower electrode and the upper electrode; Including, A dielectric powder sorting device, wherein the dielectric powder is positioned between the lower electrode and the upper electrode.

11. The dielectric powder sorting apparatus according to claim 10, wherein the dielectric powder is a charged dielectric powder.

12. 11. The apparatus for separating dielectric powder according to claim 10, further comprising a step of additionally charging the dielectric powder prior to the generation of the alternating electric field.

13. The dielectric powder sorting apparatus according to claim 12, wherein the charging step includes applying an electric field for dielectrophoresis to the dielectric powder, irradiating the dielectric powder with UV light, or generating plasma.

14. The charging step comprises: filling the chamber with a first gas, applying a voltage to generate a plasma in the dielectric powder, and then filling the chamber with a second gas; The dielectric powder sorting apparatus according to claim 12, wherein the first gas has a lower discharge start voltage than the second gas.

15. The dielectric powder sorting apparatus according to claim 10, wherein the dielectric powder is sorted according to particle size, weight, density, dielectric constant, or surface area.

16. The apparatus for sorting dielectric powder according to claim 15, wherein the magnitude of the voltage and the AC frequency are controlled according to the sorting criterion.

17. The dielectric powder sorting device comprises: The apparatus of claim 10, further comprising a dielectric substrate disposed at an upper end of the chamber and spaced apart from the upper electrode in an upward direction.

Images