KR20170040654A - Hybrid dielectric barrier discharge electrode using surface discharge and volume discharge - Google Patents

Abstract

Provided is a structure of a dielectric barrier discharge electrode. The structure comprises: a plate-shaped conductive lower electrode; a dielectric layer having surface roughness (Ra) in a range of 0.1 to 150 m, and formed on the lower electrode; and a plate-shaped conductive upper electrode having a linear pattern adhered to the dielectric layer by being mechanically overlapped by a fixing rod. The dielectric layer is formed by one among dipping, spraying, spreading, and thermal spraying processes, and generates an ion active species as an alternating current or pulse voltage of 1,500 V or less is applied.

Description

      BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a composite dielectric barrier discharge electrode using surface discharge and space discharge,

The present invention relates to a plasma or discharge electrode applied to a sterilization and air cleaning system, and more particularly to a plasma or discharge electrode which generates a discharge in a gas phase fluid such as air or water, (DBD: Dielectric Barrier Discharge) method that sterilizes bacteria and viruses existing in the air conditioner, refrigerator, washing machine, inside of vehicle, mobile phone surface and specific space by purifying the air by reacting with bacteria To a discharge electrode of a plasma display panel.

As sterilization and indoor air cleaning have become increasingly important, various methods have been developed to simultaneously remove germs, viruses, harmful particles and gaseous substances present in the room. Such techniques include filter type, electrostatic precipitator type, plasma type, UV / photocatalytic type, and hybrid type of various methods.

Among them, sterilization and air cleaning using plasma or discharge are known to have a great effect for removing contaminants. The electrons and radicals generated by the discharge phenomenon have a high oxidizing power, which removes most harmful gases such as VOCs (Volatile Organic Compounds), NOx, and CFCs and exhibits an excellent effect for sterilization. The oxygen anion is effective in reducing pollen, Dust, etc., and they are bundled together by an electric force to convert them into an easy-to-remove form.

Such a plasma discharge method can be divided into a corona discharge and a dielectric barrier discharge.

       - Corona Discharge -

       The corona discharge is composed of a sharp cathode and a corresponding electrode of flat shape. When a negative high voltage is applied to the cathode, electrons emitted from the cathode collide with the particles to generate positive ions. The positive ions accelerate to the cathode due to electrical attraction and collide with the cathode to emit high energy secondary electrons. These high-energy electrons and heavy particles create inelastic collisions that produce chemically reactive species. Fig. 1 is an electrode structure type of a corona discharge. Fig. 1 (a) shows a single-sided type and (b) shows a multi-sided type.

Since the corona type electrode is simple to manufacture and simple in structure, its cost is low, but a large amount of ozone is generated during discharge and the ozone has a long life, which causes harm to the human body. Also, the life of anion generated is very short, The sterilizing effect is also weak and the applied voltage is difficult to handle at a high pressure of 2 kV or more.

       In addition, there is a method in which the number of the cathodes is increased in order to increase the processing area because the plasma discharge volume is very small and therefore the processing area is limited to a small area. In this case, too, the micro arc (streamer) And these streamers are usually concentrated in the same place, so the treatment effect is localized.

       In order to avoid this problem, a dielectric barrier discharge method has been proposed.

- Dielectric Barrier Discharge (DBD) -

Dielectric barriers are widely used in industrial applications because they can generate high output discharges at atmospheric pressure, and they do not require complex pulse power supplies. In particular, they are widely applied to CO ₂ lasers, ultraviolet light sources, ozone generation, and pollutant disposal.

       2 is a diagram illustrating a typical dielectric barrier plasma electrode structure. As shown in FIG. 2, a dielectric barrier discharge (DBD) device is composed of two parallel metal electrodes. At least one of the electrodes is covered by a dielectric layer. If an insulator is used, the current can not flow through the electrode in the case of DC power, so that the plasma is generated by using the AC power. For stable discharge, the gap between the electrodes is limited to a few millimeters and the gas flows between these gaps.

This dielectric barrier discharge is sometimes referred to as silence discharge because there is no localized wave or noise discharge. The discharge is ignited by a sine function or a pulsed power supply. Depending on the composition, voltage and frequency of the working gas, the discharge is in the form of filament or glow. Discharge in the form of filament is generated by a micro discharge or a streamer appearing on the surface of the dielectric layer.

In this case, the role of the dielectric layer is to block the inversion current and avoid the transition of the arc, thereby enabling the operation in the continuous pulse mode and accumulating electrons on the dielectric surface to randomly distribute the streamer to the surface to induce a uniform discharge .

The Dielectric Barrier Discharge (DBD) has various variations as follows.

 * Surface Discharge (Coplanar DBD)

       When a metal electrode such as silver is provided on the surface of the ceramic plate as shown in Fig. 3 and a plate-like corresponding electrode is provided inside the ceramic plate and an alternating voltage is applied between the two electrodes, attention is paid to the striped electrode on the ceramic plate Glow discharge occurs. This discharge is distinguished from a silence discharge which will be described later when a discharge occurs. This method is effective for the generation of ozone, and the invention disclosed in Korean Patent Registration No. 10-0747178 is a prior art related to this.

       The basic structure of the surface discharge is similar, but generally, a dielectric plate is produced by making ceramic powder in the form of a slurry, a lower electrode (induction electrode) is formed by coating a metal paste on the dielectric plate, another dielectric plate is placed on the upper surface, Lt; / RTI > Thereafter, an upper electrode (discharge electrode) is formed with a metal paste on the upper dielectric layer again, and is completed by firing at a high temperature (about 1500 ° C.).

       Therefore, the manufacturing process is complicated and the cost is increased.

* Silence Discharge (Volume Discharge)

As an electrode structure of a typical dielectric barrier, when a dielectric such as glass is positioned on one or both electrodes between parallel electrodes and the interval is several millimeters and an alternating voltage is applied, a pulse-like small There are numerous discharges. This is called silent discharge and it is widely applied in industrial fields such as removal of harmful gas due to active ion generation.

4 (a) is a plate-shaped dielectric barrier electrode structure. In this method, since the electric field applied to the surface is uniform, the charges are statistically distributed in a specific shape and unevenly distributed in the dielectric, thereby inducing a streamer discharge rather than a glow discharge to reduce ultraviolet ray generation amount There is a tendency.

4 (b) is a mesh DBD structure which is a deformation of the plate DBD. Unlike general streamer discharge, the concentration of electrons in the plasma is uniformly distributed through the geometric structure of the mesh electrode as well as the electric field enhancement inside the reactor by using a mesh electrode instead of a general plate electrode, It is a structure that can generate multi-glow discharge with excellent efficiency. As a result, compared to the conventional corona discharge and general DBD discharge, plasma generation is generated with a great amount of ultraviolet ray generation and production of active species such as OH radical, O (atomic oxygen, atomic oxygen). However, there is a disadvantage that noise tends to occur, the discharge voltage is high, and the interval between the electrodes is narrow, so that the back pressure against fluid movement is large. Therefore, as disclosed in Korean Patent Publication No. 2002-0046093, in order to increase the processing capacity, electrodes of the same structure must be extended in parallel, but the structure becomes complicated and the back pressure can not be avoided due to the cross sectional area of the electrode itself.

Korean Patent Laid-Open No. 10-2009-0097340 discloses a method for solving such a problem of back pressure generation. In this publication, a method of forming a through-hole through an electrode is proposed. These through-holes are not specific to this publication but are used throughout the literature to avoid back pressure.

4 (c) shows another modified electrode structure called Micro Gap Discharge A plasma is strongly generated by using a very small discharge gap having a distance of several tens to several hundreds of micrometers between electrodes. In this method, large noise and a large amount of ozone are generated during the streamer discharge, so the applied voltage should be adjusted so that the streamer is not generated. In addition, since the probability of contact between air and active species within the plasma region is much higher than other structures, a large amount of air cleaning and sterilizing species are produced. Therefore, the disinfecting effect is better than that of the mesh DBD discharge, It is small. As a conventional technique for this, Korean Patent Laid-Open No. 10-2006-0017191 discloses an invention. However, this method has a problem that the structure is complicated and the back pressure against the fluid flow is high because a micro gap is formed between the electrodes.

- Underwater plasma discharge

Underwater discharge forms minute bubbles in water and contains gases with strong sterilizing power such as hydroxyl (OH), active oxygen (O ^- , O ₂ , O ₃ ) and hydrogen peroxide (H ₂ O ₂ ) It can be used to remove germs and viruses contained in water. Applications include household appliances such as washing machines, air conditioners, air purifiers, and humidifiers, and food processing, food processing, animal husbandry, or hospitals that require sterilization disinfection.

The plasma electrode used for such underwater discharge is also mainly used as a dielectric barrier electrode. Such an electrode basically does not deviate from the above-mentioned plasma electrode type. As a conventional technique for this, Korean Patent No. 10-0924649 and Japanese Patent Laid-Open No. 10-2009-009675 disclose the invention.

Korean Patent No. 10-0747178 Korean Patent Publication No. 10-2002-0046093 Korean Patent Publication No. 10-2009-0097340 Korean Patent Publication No. 10-2006-0017191 Korean Patent No. 10-0924649 Korean Patent Publication No. 10-2009-009675

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide an ozone generator which is stable in discharge, And an object of the present invention is to provide a discharge type electrode structure.

The purpose of the above is;

A lower electrode made of a conductor in the form of a plate;

       A dielectric layer which is fixed on the lower electrode and has a surface roughness (Ra) in a range of 0.1 mu m to 150 mu m;

       And an upper electrode fixed to the upper surface of the dielectric layer, the upper electrode being a plate-shaped conductor having a linear pattern;

       Wherein the dielectric layer is formed by any one of dipping, spraying, spreading, and thermal spraying, or a combination thereof. This is achieved by a composite dielectric barrier discharge electrode.

Another object of the present invention is to provide

       A plate-shaped dielectric layer having a surface roughness (Ra) in a range of 0.1 mu m to 150 mu m;

       A lower electrode in the form of a plate-like conductor tightly fixed to the lower portion of the dielectric layer;

       A plate-shaped conductive upper electrode closely adhered to the upper surface of the dielectric layer and having a linear pattern;

And a composite dielectric barrier discharge electrode which simultaneously uses a surface discharge and a spatial discharge.

According to an aspect of the present invention,

       At least one of the conductor upper electrode and the dielectric layer, and between the conductor lower electrode and the dielectric layer;

Any one or more of a dielectric adhesive or a conductive adhesive may be involved for enhancing adhesion.

According to another aspect of the present invention,

       The linear pattern of the conductive upper electrode may be at least one selected from a mesh, a honeycomb, a circle, an ellipse, a needle, a polygon, a straight line, a curve, and combinations thereof.

According to still another aspect of the present invention,

       The line width (line width) of the linear pattern of the conductive upper electrode may range from 0.01 mm to 5 mm.

According to still another aspect of the present invention,

       The total thickness of the dielectric layers may range from 0.01 mm to 3 mm.

According to still another aspect of the present invention,

       The dielectric layer may be at least one layer, and each dielectric layer may be made of the same material, different materials, or two or more kinds of dielectric materials.

According to still another aspect of the present invention,

       A protective coating may be formed on at least one of the lower electrode, the upper electrode, and the dielectric layer using any one of ceramics, glass, polymer materials, and combinations thereof.

According to still another aspect of the present invention,

At least one through hole may be formed in the composite discharge electrode, and the through hole may be formed in a circular shape, a square shape, an elliptical shape, a polygonal shape, or a combination thereof.

According to still another aspect of the present invention,

The composite discharge electrode may have a shape of a plate, a cylinder, or a square tube having a curvature.

According to still another aspect of the present invention,

       And a dielectric layer and an upper electrode may be further formed on the lower surface of the lower electrode.

The discharge electrode of the present invention having the above-described structure has a low noise, excellent discharge efficiency, a large number of active species generated, a long life of the structure, a low back pressure of air, Purification, disinfection, as well as the air can be removed to remove the smell of air.

In addition, since the plasma electrode structure can be variously configured according to the characteristics of the required application, it is possible to solve most of the limitations of the electrode design according to the conventional plasma electrode structure, which is greatly advantageous for miniaturization.

Therefore, the electrode structure of the present invention is not limited to the sterilization and air cleaning field but can be easily applied to liquid phase such as other gas phase fluids and water, and thus can be easily applied to various applications.

1 is a view showing a typical corona discharge electrode structure.
2 is a diagram illustrating a typical dielectric barrier discharge electrode structure.
3 is a view showing a typical surface discharge electrode structure.
Fig. 4 is a diagram showing a typical silent discharge (Voltage DBD) electrode structure. Fig. 4 (a) shows the plate DBD, Fig. 4 (b) shows the mesh DBD and Fig. 4 (c) shows the micro gap DBD.
5 is a view illustrating an electrode structure according to an embodiment of the present invention.
6 is a conceptual diagram illustrating a discharge region according to an embodiment of the present invention.
7 is a linear pattern of an upper electrode according to an embodiment of the present invention.
8 is an electrode structure according to another embodiment of the present invention.
9 is an electrode structure according to another embodiment of the present invention.
10 is an electrode structure according to another embodiment of the present invention.
11 is an electrode structure according to another embodiment of the present invention.
12 is an electrode structure according to another embodiment of the present invention.
13 is a graph illustrating the performance of an electrode according to an embodiment of the present invention.

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

There are various types of dielectric barrier discharge electrodes. However, these electrodes generally have a structure in which the electrodes and the dielectric layer are formed in parallel to each other in a plate shape. The discharge region appears parallel to the electrode array and the fluid flow occurs parallel to the electrode array. Some of the electrodes have a cylindrical shape, but the results are the same. In the case of the micro gap method, a complicated design is required in order to maintain the interval of the micro unit between the electrodes, the fluid passage interval is reduced, and the back pressure against the fluid flow is generated and the noise is increased. It also uses phrases.

Due to these structural limitations, the conventional electrode structure has a fundamental limitation of electrode design that can not easily meet the requirements of the application.

In order to overcome these limitations, the present invention adopts a surface discharge method with a low back pressure against fluid flow as a basic structure, a method of forming a dielectric layer as a surface discharge manufacturing process, a method of forming an upper electrode (discharge electrode) And thus, an economical and efficient discharge electrode structure has been proposed.

That is, the lower dielectric layer among the lower and upper dielectric layers is omitted and a dielectric plate is directly formed on the induction electrode by using a plate-shaped metal plate other than metal paste. The upper electrode (discharge electrode) also uses a method of mechanically overlapping a plate-shaped metal plate. This makes it possible to realize a hybrid discharge electrode of surface discharge and volume discharge.

This seems to be a simple invention, but as yet untried method, it is necessary to be able to control arc discharge in consideration of plasma and discharge. The electrode of the present invention can simplify the structure and manufacture because it can omit the thermocompression process used at the time of manufacturing the surface discharge electrode and the high temperature firing process and simultaneously generate the surface discharge and the space discharge. Driving is enabled and the efficiency of the electrode is improved.

FIG. 5 is a conceptual view showing a discharge electrode structure and a discharge region according to an embodiment of the present invention, an assembly sectional view and a sectional view of a resultant structure. FIG.

5, the dielectric barrier discharge electrode structure 100 of the present invention is formed by forming a dielectric layer 130 on the lower conductor electrode 110 and forming a conductive pattern having a linear pattern thereon, Body upper electrode 120 is formed and the discharge region 140 is formed in the vicinity of the upper electrode 120 along the linear pattern of the upper electrode 120. [ In FIG. 5, reference numeral 140 denotes a discharge 140 region, which is expressed in a dark color.

       The conductor lower electrode 110 or the conductor upper electrode 120 is formed using a conventional processing method such as etching, pressing, and machining. The thickness of the conductor electrode does not greatly affect the performance of the electrode, but in the case of the thickness of the upper electrode 120, a range of 2 mm or less is preferable for smooth surface discharge discharge.

       The dielectric layer 130 is formed on the lower electrode 110 by using a dipping and spraying process in which an appropriate solvent is immersed or coated in a solution prepared by mixing a dielectric powder and an appropriate binder, . The dielectric powder may be formed using a thermal spraying process or a powder coating process.

The dielectric layer 130 is formed of a ceramic material having electrical insulation and dielectric properties at the same time. The dielectric layer 130 may be formed of a material selected from the group consisting of quartz, glass, aluminum oxide, titanium oxide, magnesium oxide, silicon oxide, silver phosphate, silicon carbide, indium oxide, , Zinc oxide, iron oxide, lead titanate zirconate, and carbon nanotubes. The thickness is, for example, several mu m to several mm and the area thereof can be arbitrarily set according to the processing capacity, for example, it may be several mm ² to several hundreds cm ² .

       Typical Micro Gap Dielectic Barrier Discharge (DBD) has a gap of 200 μm or less, and the corresponding value in terms of surface roughness is Ra 200 μm. Therefore, the surface roughness Ra of the dielectric layer in the present invention is preferably 200 占 퐉 or less. According to the present invention, for the uniformity of discharge, it is preferable that Ra is in the range of 0.1 μm to 150 μm, which is 75% of 200 μm, more preferably in the range of 0.1 μm to 50 μm.

       As shown in FIG. 6, the surface roughness of the dielectric layer 130 forms a fine internal space when closely adhering to the linear pattern of the upper electrode 120 to generate a spatial discharge (micro gap dielectric barrier discharge) This occurs simultaneously with the surface discharge, so that a composite discharge structure is formed. 6 is a conceptual diagram showing a discharge region in a composite type discharge electrode. The surface discharge 141 occurs on the side surface of the upper electrode 120 and the spatial discharge 142 occurs in the inner space between the upper electrode 120 and the dielectric layer 130. Since the ratio of the generation of the surface discharge 141 and the generation of the spatial discharge 142 changes according to the surface roughness of the dielectric layer 130 and the line width of the linear pattern of the upper electrode 120, do.

The dielectric layer 130 may be formed of a mixture of two or more dielectric compositions, and may be formed of one or more layers. Further, when one or more dielectric layers 130 are formed, the material of each dielectric layer 130 may be the same or different. When the dielectric layer 130 is a mixture of dielectrics, the relative dielectric constant can be adjusted to a desired level through the mixing ratio. In addition, the characteristics of the discharge 140 formed through the change in the number, the total thickness, and the material of the dielectric layer 130 can be changed, and the electrode characteristics can be enhanced.

      The linear pattern of the upper electrode 120 may include at least one selected from the group consisting of a grid, a honeycomb, a circle, an ellipse, a needle, a polygon, a straight line, a curve, So that the entire pattern is energized from the electric power supply terminal 121. [ It is also possible to divide the pattern into two or more zones to energize. An example of several linear patterns is shown in Fig.

     The conductive upper electrode 120 (discharge electrode) is closely contacted with the dielectric layer 130 by a mechanical overlap, and a pin-shaped fixing table 150 can be used for close contact. It is preferable that the surface shape of the dielectric layer 130 and the surface shape of the upper electrode 120 coincide with each other. The fixing table 150 is provided to support the upper and lower surfaces of the electrodes. The upper surface of the fixing table 150 presses the upper surface of the upper electrode 120 and the lower surface of the fixing table 150 fixes the lower surface of the lower electrode 110 with a frame or the like. The material of the fixing table 150 is a material having an insulating property, and the structure of the fixing table 150 is generally sufficient.

       Also, a dielectric adhesive or a conductive adhesive 160 may be interposed between the upper electrode 120 and the dielectric layer 130 as shown in FIG. The dielectric adhesive or conductive adhesive 160 may be used together. As a result, the strength and uniformity of adhesion can be further increased.

       9, a dielectric layer 130 of a plate shape is first provided, and the lower electrode 110 and the upper electrode 120 are mechanically overlapped with the dielectric layer 130. In this case, ≪ / RTI > In this case, at least one of the dielectric adhesive and the conductive adhesive 160 may be used when the lower electrode 110 and the upper electrode 120 are closely contacted as described above, thereby further increasing the adhesion strength and uniformity.

       In the present invention, at least one of the dielectric layer 130, the conductor lower electrode 110, or the upper electrode 120 may be formed of a material selected from the group consisting of ceramic, glass, polymer materials, and combinations thereof for corrosion resistance, durability, A protective coating can be applied.

       The surface discharge method is a structure that generates discharge on the surface, and the gas flow occurs on the plate electrode. However, depending on the application of the electrode, the gas flow may need to be perpendicular to the plate electrode. In this case, at least one through hole 170 may be formed in the direction perpendicular to the plate-like electrode as shown in FIG. That is, one or more through-holes may be formed in the plate-shaped electrode structure so that the fluid may move through the through-holes.

The shape of the through hole 170 may be circular, square, elliptical, polygonal, or any combination thereof. The hole 170 may be formed by variously combining the sizes, types, Can be changed.

11, the plate-shaped electrode may be in the shape of a concave (or convex, see Fig. 11 (a)) having a curvature instead of a flat plate, and the plate- Various shapes such as a cylindrical shape (see FIGS. 11 (b) and 11 (c)) and a rectangular tube shape (see FIG. 11 (d)

As shown in FIG. 12, two electrodes according to the present invention are overlapped with the lower electrodes 110 in close contact with each other (see FIG. 12 (a)), or an additional dielectric layer 130 is formed symmetrically with the lower end of the lower electrode, (See FIG. 12 (b)). In this case, since the discharge occurs at the upper and lower ends of the electrode at the same time, the function of the electrode can be further improved.

The voltage applied to the conductor lower electrode 110 and the conductor upper electrode 120 is preferably in a range of 1,500 V or less, thereby allowing generation of anion and ion clusters suitable for the application. Since the applied voltage of a general corona discharge electrode and a dielectric barrier discharge electrode is 2,000 V or more, the electrode according to the present invention is capable of driving at a low voltage.

The electrode in the present invention generates ultraviolet rays, electrons, active oxygen, ozone, OH ions and radicals by the discharge 140, and the harmful gas in the fluid passing through the electrode is harmless Changed, sterilized, and beneficial ions, radicals, active oxygen, etc. are discharged out of the electrode, thereby further removing viruses and germs present on the outside of the electrode. Such a reaction is based on the principle of low-temperature plasma.

In the present invention, the fluid may be a gas such as air or a liquid such as water. When the electrode structure described above is provided with an appropriate waterproof structure and then placed in water, underwater discharge can be easily and efficiently generated. In addition to sterilization and air cleaning, it can be applied to various fields such as humidifier and sterilized water.

Generally, a surface discharge type electrode is manufactured by forming a dielectric plate, applying a metal paste on the dielectric plate to form a lower electrode (induction electrode), placing another dielectric plate on the upper surface, and thermally compressing the dielectric plate. Thereafter, an upper electrode (discharge electrode) is formed with a metal paste on the upper dielectric layer again, and is completed by firing at a high temperature (about 1500 ° C.). Therefore, the manufacturing process is complicated and the cost is increased. In addition, the micro-pore discharge electrode has a complicated structure due to the formation of minute gaps, and there is a problem that the back pressure against the fluid flow is large due to the micro gap.

Unlike this, it is considered that a structure in which a dielectric layer is directly formed on a lower electrode and an upper electrode is separately fabricated as in the present invention and a patterned upper electrode is mechanically closely contacted by a usual fixing table has not been attempted to date.

       The electrode structure of the present invention as described above may be regarded as a comparatively simple invention on one side. However, it is an invention that can only appear when there is a considerable consideration on the principle of plasma generation and requirements of application.

First, as a dielectric forming method, a dielectric material can be formed directly on the lower electrode, and the dielectric material can be easily formed to an appropriate thickness regardless of the shape of the lower electrode.

Second, the upper electrode is separately fabricated and mechanically adhered to the dielectric layer. Thus, the screen printing or metal deposition process, which is an upper electrode formation method, can be omitted in the manufacturing process of the conventional surface discharge electrode, thereby simplifying the process.

Third, formation of the lower dielectric layer, thermocompression of the electrodes and dielectric high-temperature firing process are omitted in the manufacturing process of the conventional surface discharge electrode, so that the overall electrode structure and manufacturing process can be simplified and the cost can be reduced.

Fourth, since the structure and fabrication are simplified, various deformable structures are possible, and various shapes of electrode structures are possible depending on the application.

Fifth, the surface discharge and the volume discharge due to the micro-gap of the linear pattern according to the surface discharge are simultaneously generated and the electrode efficiency is improved and the low voltage driving is enabled , It is possible to minimize the back pressure against the fluid flow.

Hereinafter, the present invention will be described in detail by way of examples.

(Example 1)

To evaluate the performance of the discharge electrode, a module consisting of a fluid inlet, a discharge electrode, and a fluid outlet was used. The lower electrode of the conductor was made of stainless steel 403, and a disk shape having a diameter of 50 mm and a thickness of 1 mm was prepared. The lower electrode of the conductor was made of water and the alumina and zirconium titanate lead zirconate powder having a particle size of 1-2 μm were made dielectric after using the binder of the SiO ₂ series forming a dielectric layer having a thickness of 300μm by a conventional coating process and then it dried 150 ℃ 1 hour.

The upper electrode 120 having the same size as that of the lower electrode 110 is prepared in the form of a mesh having a thickness of 0.3 mm and a line width of 0.3 mm and the upper electrode 120 is closely contacted with the dielectric layer 130 with a plastic- And the electrode structure was completed.

Then, a pulse voltage of 900 V and a frequency of 280 Hz was applied to the electrode structure, and the concentration of anion and ozone generated through the ion counter and the ozone analyzer were measured at the outlet of the air. Escherichia coli smearing on an agar medium was placed at a distance of 20 cm from the lead-out portion, and sterilization power was measured by observing sterilization halo after 24 hours.

As a result, the amount of generated negative ions was 315,000 / cm ³ , the concentration of ozone was 0.03 ppm or less, and more than 99.9% of bacteria were sterilized.

(Example 2)

The electric energy applied to the electrode, that is, the number of negative ions generated as the pulse width increases, is shown in FIG. As shown in FIG. 13, the number of negative ions generated as the pulse width increases increases rapidly, and as the pulse width approaches 100 μs, the number of negative ions increases to 1,200,000 / cm ³ or more.

(Comparative Example 1)

On the other hand, in the needle-like corona type electrode structure for comparison with the present invention, the amount of generated negative ions was 180,000 / cm ³ , and the sterilization effect was insignificant even after 72 hours. In addition, since the voltage was applied over 2kV to generate the plasma, the handling and the risk of use were very large.

   As described above, the present invention is not limited to the above-described specific preferred embodiments, and any person skilled in the art can make various modifications without departing from the gist of the invention claimed in the claims. And such changes are within the scope of the claims.

100: discharge electrode structure
110: conductive lower electrode 111: lower electrode terminal
120 conductive upper electrode 121 upper electrode terminal
130 dielectric layer
140 ......... discharge (area)
141 Surface discharge (area) 142 Spatial discharge (area)
150 ....... fixed base
160 ....... Dielectric adhesive or conductive adhesive
170 ....... through-hole

Claims (11)

A lower electrode made of a conductor in the form of a plate;
A dielectric layer which is fixed on the lower electrode and has a surface roughness (Ra) in a range of 0.1 mu m to 150 mu m;
And an upper electrode fixed to the upper surface of the dielectric layer, the upper electrode being a plate-shaped conductor having a linear pattern;
Wherein the dielectric layer is formed by any one of dipping, spraying, spreading, and thermal spraying, or a combination thereof. The composite dielectric barrier discharge electrode
A plate-shaped dielectric layer having a surface roughness (Ra) in a range of 0.1 mu m to 150 mu m;
A lower electrode in the form of a plate-like conductor tightly fixed to the lower portion of the dielectric layer;
A plate-shaped conductive upper electrode closely adhered to the upper surface of the dielectric layer and having a linear pattern;
Wherein the composite dielectric barrier discharge electrode (10), which simultaneously uses the surface discharge and the spatial discharge,
3. The method according to any one of claims 1 to 2,
At least one of the conductor upper electrode and the dielectric layer, and between the conductor lower electrode and the dielectric layer;
Characterized in that at least one of a dielectric adhesive and a conductive adhesive is interposed for enhancing the adhesion. The composite dielectric barrier discharge electrode
4. The method according to any one of claims 1 to 3,
Wherein the linear pattern of the conductive upper electrode is at least one selected from the group consisting of a mesh (grid) shape, a honeycomb shape, a circular shape, an elliptical shape, a needle shape, a polygonal shape, a straight shape, a curved shape, , A composite dielectric barrier discharge electrode that simultaneously uses surface discharge and space discharge
5. The method according to any one of claims 1 to 4,
Wherein the conductive upper electrode has a line width (line width) in a range of 0.01 mm to 5 mm, and the composite dielectric barrier discharge electrode
6. The method according to any one of claims 1 to 5,
Wherein the total thickness of the dielectric layers is in the range of 0.01 mm to 3 mm. The composite dielectric barrier discharge electrode
7. The method according to any one of claims 1 to 6,
Wherein the dielectric layer is at least one layer and each dielectric layer is made of the same material, different materials, or two or more kinds of dielectric materials. The composite dielectric barrier discharge electrode
8. The method according to any one of claims 1 to 7,
Wherein a protective coating is formed on at least one of the lower electrode, the upper electrode, and the dielectric layer by using any one of ceramics, glass, polymer materials, and combinations thereof. Barrier discharge electrode
9. The method according to any one of claims 1 to 8,
Wherein at least one through hole is formed in the composite discharge electrode, and the through hole is formed by a circle, a rectangle, an ellipse, a polygon, or a combination thereof. Barrier discharge electrode
10. The method according to any one of claims 1 to 9,
Characterized in that the composite discharge electrode has a shape of a plate-like, cylindrical, or rectangular tube having a curvature. The composite dielectric discharge electrode
11. The method according to any one of claims 1 to 10,
And a dielectric layer and an upper electrode are further formed on a bottom surface of the lower electrode. The composite dielectric barrier discharge electrode

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