KR20230041613A - Apparatus for generating the plasma including hydroxyradical - Google Patents

Abstract

According to the present invention, a plasma generation device including hydroxyl radicals is disclosed. Specifically, the plasma generation device including hydroxyl radicals comprises: a plasma generation unit which generates plasma containing hydroxyl radicals through high-voltage discharge; and a temperature and humidity control unit which is detachably coupled to a lower part of the plasma generation unit, and generates and supplies water vapor to the plasma generation unit. The plasma generation unit comprises: a plasma housing having a plasma discharge port for discharging plasma containing hydroxyl radicals formed at an upper part or a side part, and having a water vapor inlet communicating with the temperature and humidity control unit so that the water vapor flows in formed at a lower part; a discharge electrode having a sharp needle shape at an upper end and formed on one side of the plasma housing; a discharge terminal supplied from the outside to apply a high voltage to the discharge electrode; a ground electrode formed on the other side of the plasma housing; and a ground terminal electrically connected to the ground electrode and exposed to the outside. Accordingly, plasma generation is effectively promoted, but arc transfer and ozone generation can be prevented.

Description

Plasma generator including hydroxyradical {Apparatus for generating the plasma including hydroxyradical}

The present invention relates to a plasma generator, and more particularly, to a plasma generator including hydroxyl radicals capable of generating a large amount of hydroxyl radicals based on the principle of atmospheric pressure low-temperature plasma.

Since Corona 19 was first reported in Wuhan, China on December 31, 2019, the world has faced an unprecedented crisis caused by a pandemic. As invisible microorganisms threaten the safety of all mankind, they have brought a tremendous blow to the economy, society, and culture in everyday life.

Countries are developing and inoculating COVID-19-related treatments and vaccines to evolve the pandemic, but microorganisms that threaten the survival of mankind, such as various mutant viruses and black mold, are constantly appearing. Therefore, fields such as antimicrobial, quarantine, and infection prevention are no longer limited to the aspect of health, but have become essential fields for human beings to lead a normal life.

There are numerous ways to kill germs and viruses, such as heat such as flame, light such as UV-C, and chemicals such as ethanol. is difficult, and when the above methods are applied to air or the surface of an object, which is a medium for microorganisms to enter the human body, problems such as generation of secondary harmful substances and damage and destruction of the treatment target are limited. In addition, chemical substances have different sterilization mechanisms depending on their components, and when continuously exposed to microorganisms to be sterilized, microorganisms tend to have resistance and are not suitable for general use.

Recently, sterilization methods such as plasma and photocatalyst, which are called the fourth state of matter, are harmless to the human body, are universal, and are in the spotlight for their excellent sterilization ability. They effectively remove or destroy microbial cells by generating active species such as ions, ozone (O3), and hydroxyl radicals ( OH) using electric fields or light. It also quickly reacts and removes organic chemicals such as dust and odorous substances. Since they produce water and carbon dioxide harmless to the human body as end products and destroy them by reacting with any microorganisms or organic substances, they have many advantages in terms of environment and economy.

However, ozone generated by plasma and photocatalyst increases its sterilizing power when it exceeds a certain concentration, but has a problem of causing damage to the respiratory system in the human body, so there is a limit to its use. The problem is that its lifespan is very short.

In addition, the photocatalyst requires light of a specific wavelength, which is in the ultraviolet region, and eventually must be accompanied by ultraviolet rays. In particular, since plasma has electromagnetic and chemical properties that cannot be observed in conventional materials, it is a field that is already variously applied in real life technically and industrially, such as semiconductors and displays.

The plasma state is a state in which neutral gas is ionized into ions and electrons due to a high energy source such as electrical energy or thermal energy, and is composed of not only ions and electrons but also non-ionized neutral particles and chemically active species such as radicals. It is largely divided into high-temperature plasma and low-temperature plasma. In the case of high-temperature plasma, it is difficult to apply it to real life such as sterilization because its temperature reaches several thousand to several tens of thousands of degrees Celsius.

In the case of low-temperature plasma, only the temperature of electrons is high and the temperature of ions and neutral particles is low, so it is suitable for sterilization of materials or conditions in which high temperatures cannot be applied. The high energy of electrons enables various chemical reactions inside, and the low energy of ions and neutral particles enables plasma treatment without damaging reactants.

Low-temperature plasma is created by applying a high electric field (electric field) at a low temperature, and it is more easily generated at a lower pressure of about 1 mTorr to 100 Torr than atmospheric pressure (about 760 Torr). The reason is that there are many gas particles in the atmospheric pressure, so the number of collisions is frequent, and because of this, the mean free path of the gas is short, so a sufficient amount of energy cannot be generated. However, in a vacuum state, the average stroke distance of the gas is long, and it can generate enough energy to generate plasma.

However, since an expensive vacuum system must be built, there are limitations in terms of economic feasibility and convenience, so research to generate plasma under atmospheric pressure is being actively conducted.

Atmospheric pressure low-temperature plasma can be driven only with gas and a low-voltage power supply, can minimize electrical damage and thermal damage to the sterilization target, and generates a large amount of active species that exhibit strong sterilization, so it is plasma for sterilization. can be said to be suitable for In particular, it is attracting attention as a technology that can supplement the problems of conventional sterilization technologies in that it does not cause modification of proteins by heat because the temperature is not high and does not generate substances harmful to the environment.

Plasma used in our daily life mostly uses DC discharge. DC discharge is a method of generating plasma by applying a voltage between the anode and cathode and generating plasma. It is divided into dark discharge (dark discharge), glow discharge (bright discharge), and arc discharge according to the current-voltage relationship.

Dark discharge is characterized by a very high voltage of the electrode instead of a low amount of current, and in most cases, the luminescence phenomenon is weak. A region with a relatively high current among dark discharges is called a corona discharge.

Corona discharge is a typical atmospheric pressure low-temperature plasma, and is composed of a sharp or thin discharge electrode and a non-pointy flat ground electrode. An unequal electric field is formed due to charges accumulated on the pointed parts of the discharge electrode, which facilitates plasma generation even under atmospheric pressure, and is characterized by the generation of ion wind. In addition, corona discharge is an advantageous type of discharge electrode for plasma formation, and has the advantage of being able to easily generate plasma even under atmospheric pressure and low temperature.

However, plasma is locally generated at the electrode portion, and the generated volume is narrow and unstable, so it is easy to transfer to an arc furnace, and thus ozone is easily generated.

Among the active species generated by plasma, hydroxyl radical ( OH) is a substance with the strongest sterilizing power. It is harmless to the human body because it is reduced to oxygen and water after reacting with pollutants and can destroy all microorganisms and organic substances. A device that provides a stable supply is required.

Hydroxide radicals are as unstable as they are highly reactive and have a short lifespan, so there is a problem in that a sufficient amount must be continuously treated and it is difficult to efficiently sterilize a large area or space.

Indoor air sterilization devices using hydroxyl radicals have been developed in Korean Patent No. 10-1913301 and Registered Patent No. 10-1708799, but ozone or hydrogen peroxide, which can be harmful to the human body when the concentration exceeds a certain level, is used as a radical generation initiator. Therefore, there is a problem in that a safety device must be separately prepared so that they are not exposed to the human body.

In addition, Korean Patent Registration No. 10-1866545 suggests a sterilizer that generates active species using the dielectric barrier discharge principle. However, this is a method of generating active species by generating ozone, which is the primary product, with plasma and then supplying water vapor to induce the generation of active species. Since water vapor is generated by ultrasonic vibration, there is a possibility that it may not react with ozone and change into active species because it is close to a liquid state. Since it reacts outside the discharge port, there is a problem in that ozone that has not been extinguished or changed into active species before that time can be discharged to the outside as it is.

Korean Registered Patent No. 10-1913301 (2018.10.24.) "Air sterilization device that generates and discharges hydroxyl radicals that can be used in indoor environments" Korean Registered Patent No. 10-1708799 (2017.2.15.) "Sterilization and purification device using hydroxyl radical" Korean Registered Patent No. 10-1866545 (2018.6.4.) "Plasma sterilizer that produces active species using a plurality of rod-shaped electrodes and dielectric tubes"

Accordingly, the present invention was developed to solve the above-described conventional problems, and an object of the present invention is to cause dark discharge at a low voltage lower than the voltage at which corona discharge occurs and maintain an extremely low current so that there is no concern about ozone generation and transition to an arc furnace. , Minimizes ozone generation by causing a fine dark discharge in the pores in the discharge electrode of porous material to form an electric field between the droplets micronized by the pores and the ground electrode to generate stable plasma even for a long time reaction without generating light and sound. It is to provide a plasma generator including hydroxyl radicals capable of generating a large amount of hydroxyl radicals capable of sterilizing a wide treatment area due to porous micro-discharges generated on the front surface of electrodes.

Another object of the present invention is to generate hydroxyl radicals that are not harmful to the human body by supplying appropriate water vapor instead of ozone or hydrogen peroxide harmful to the human body in order to generate hydroxyl radicals that exhibit strong sterilizing power when an environment of appropriate temperature and humidity is created. To provide a plasma generating device including a.

Plasma generating device including hydroxyl radicals according to the present invention for achieving the above object is detachably coupled to a plasma generating unit generating plasma including hydroxyl radicals by high voltage discharge and a lower portion of the plasma generating unit In the plasma generating device including hydroxyl radicals composed of a temperature and humidity control unit for generating water vapor and supplying it to the plasma generating unit, the plasma generating unit has a plasma discharge port for discharging plasma containing hydroxyl radicals formed on an upper or side portion of the plasma generating unit and a lower portion of the plasma generating unit. a plasma housing having a water vapor inlet communicating with the temperature and humidity controller so that water vapor can flow into the housing; a discharge electrode formed in a needle shape with a sharp upper end and formed on one side of the plasma housing; a discharge terminal for applying a high voltage to the discharge electrode from the outside; a ground electrode formed on the other side of the plasma housing; and a ground terminal electrically connected to the ground electrode and exposed to the outside.

According to the present invention described above, there are the following effects.

First, plasma containing hydroxyl radicals under atmospheric pressure is applied by applying a voltage corresponding to a dark discharge with a current lower than corona discharge using a needle-shaped discharge electrode made of a porous material capable of uniformly absorbing water including electrolyte into the pores. Although the generation is effectively promoted, there is an effect of preventing arc transfer or ozone generation due to this.

Second, the treatment area can be increased by inducing micro-discharge with the porous structure of the discharge electrode.

Third, it is possible to generate a large amount of hydroxyl radicals while minimizing by-products harmful to the human body by supplying water vapor instead of ozone as a precursor necessary for generating hydroxyl radicals to provide optimum temperature and humidity for plasma generation.

1 is a perspective view showing the appearance of a plasma generating device including a hydroxyl radical according to an embodiment of the present invention.
Figure 2 is an exploded perspective view of the present invention shown in Figure 1
Figure 3 is a cross-sectional perspective view of the present invention shown in Figure 1
Figure 4 is a cross-sectional view showing various embodiments of the discharge electrode of the present invention shown in Figure 2
5 is a cross-sectional perspective view showing a plasma generating device including a hydroxyl radical according to another embodiment of the present invention.
6 is an operating state diagram of the present invention
7 to 9 are cross-sectional views showing a plasma generating device including a hydroxyl radical according to another embodiment of the present invention.

Hereinafter, an embodiment according to the present invention will be described in more detail with reference to the accompanying drawings.

For reference, the description with reference to the drawings is for easier understanding of the present invention, and the scope of the present invention is not limited thereto. And, in describing the present invention, if it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted.

1 is a perspective view showing the appearance of a plasma generating device including a hydroxyl radical according to an embodiment of the present invention.

Referring to the drawing, the present invention is largely divided into a plasma generating unit 100 that generates plasma containing hydroxyl radicals by discharge with a high voltage, and a plasma generating unit 100 coupled to a lower portion of the plasma generating unit 100 and generating water vapor. It may be composed of a temperature and humidity controller 200 supplied to the plasma generator 100 .

First, the plasma generating unit 100 will be described with reference to FIGS. 2 to 4 together. Figure 2 is an exploded perspective view of the present invention shown in Figure 1, Figure 3 is a cross-sectional view of the present invention shown in Figure 1, Figure 4 is a cross-sectional view showing various embodiments of the discharge electrode of the present invention shown in Figure 2 am.

The plasma generating unit 100 may be implemented by including a plasma housing 110, a discharge water tank 120, a discharge electrode 130, a discharge terminal 140, a ground electrode 150, and a ground terminal 151. there is.

The plasma housing 110 accommodates the discharge reservoir 120, the discharge electrode 130, the discharge terminal 140, the ground electrode 150, and the ground terminal 151 therein, and plasma is generated. Provide space (sheath).

To this end, the plasma housing 110 is made in the shape of a container, and a plasma discharge port 111 is formed on the upper surface to discharge the plasma generated therein upward.

At this time, the plasma discharge port 111 may have a structure in which a plurality of holes are formed.

A steam inlet 112 is formed on the lower surface of the plasma housing 110 to allow the vaporized water vapor generated by the temperature and humidity controller 200 to flow in.

In this case, a plurality of steam inlets 112 may be formed at intervals while forming a circular or long hole shape having a predetermined inner diameter on the lower surface of the plasma housing 110, but is not limited thereto.

Next, the discharge water reservoir 120 is fixed and installed on the inner bottom of the plasma housing 110 . The discharge reservoir 120 is made in the shape of a container to accommodate water, and may be composed of a discharge base 121, a discharge cover 123, and a sealing member 125 to be opened and closed.

The discharge base 121 may have four side surfaces and a bottom inside to accommodate water, and an upper surface may have an open structure, but is not limited thereto.

And the cover 123 for discharge is provided to close or open the top of the base 121 for discharge.

In addition, a sealing member 125 is provided between the discharge base 121 and the discharge cover 123 to prevent leakage of water therein. At this time, the sealing member 125 is provided along the edge to which the discharge base 121 and the discharge cover 123 are in close contact.

More specifically, a fixing member 122 capable of fixing the discharge electrode 130 is formed at the bottom of the discharge base 121, and a hole is formed so that the discharge terminal 140 can penetrate and protrude into the inside. It can be.

A discharge electrode hole 124 is formed at the center of the discharge cover 123 so that the discharge electrode 130 can pass through and be exposed to the outside.

For reference, it is preferable that the sealing member 125 is also installed between the discharge electrode hole 124 and the discharge electrode 130 .

Next, the discharge electrode 130 is a means for generating plasma together with the ground electrode 150. The lower part may have a columnar shape such as a cylinder, and the upper part is tapered to form a sharp needle shape.

The discharge electrode 130 is vertically installed and fixed inside the discharge reservoir 120 by the fixing member 122 .

And, the upper end of the discharge electrode 130 penetrates the discharge electrode hole 124 and protrudes to the outside of the discharge reservoir 120 to be exposed. That is, the lower part of the discharge electrode 130 is submerged in the water contained in the discharge water reservoir 120, and the upper part is exposed to the air.

Preferably, as shown in FIG. 4(b), the discharge electrode 130 is preferably made of a hydrophilic porous material.

This is because water including electrolyte is absorbed into the discharge electrode 130 through numerous pores by capillary action and delivered to the top, and the delivered water is uniformly dispersed on the surface of the discharge electrode 130, resulting in microdischarge and ionization. Since the treatment area is increased, the hydrophilic porous material can solve the disadvantage of locally limited corona discharge.

More specifically, as the material of the discharge electrode 130, a hydrophilic material may be used, or a material treated with a hydrophilic material may be used even if it is not hydrophilic.

For example, polyethylene-based (LDPE, HDPE, UHMWPE, etc.), polypropylene-based, Teflon-based, polyurethane-based, non-woven fabric, etc. may be used. In addition, ceramics such as diatomaceous earth, silica, zeolite, and lime may also be used.

As another embodiment, as shown in FIG. 4(c), the discharge electrode 130 may use both a metal material and a hydrophilic porous material. That is, it is composed of a first electrode body 131 made of a hydrophilic porous material, and a second electrode body 132 made of a metal material penetrated and inserted into the center of the first electrode body 131 in the same shape as the core material. can

As another embodiment, as shown in FIG. 4(d), the discharge electrode 130 may use a capillary body 133 having a thin capillary 133a in the center. Water is delivered to the upper end through the capillary body 133 and discharge is performed.

Next, the discharge terminal 140 penetrates the bottom of the discharge reservoir 120 and protrudes into the inside.

Therefore, the discharge terminal 140 can apply a high voltage from the outside while submerged in water.

To apply voltage, a discharge terminal connector 141 is provided between the plasma generating unit 100 and the temperature/humidity adjusting unit 200, and an end thereof is exposed to the outside. And, the discharge terminal connector 141 is electrically connected to the discharge terminal 140 .

In addition, a separate discharge terminal bracket 142 is provided between the plasma generator 100 and the temperature/humidity controller 200 to fix the discharge terminal connector 141 . For reference, the discharge terminal bracket 142 is made of an insulator, and when a high voltage is applied when only the discharge terminal connector 141 is present, instability or instability can be prevented.

Therefore, a high voltage can be applied to the water in the water storage tank 120 for discharge through the discharge terminal connector 141 from a separate high voltage generator (not shown).

Next, the ground electrode 150 is disposed horizontally on the upper side of the discharge electrode 130, and is formed in a linear or reticular shape.

In the case of using a conventional plate-shaped ground electrode 150, it is preferable to use a linear or mesh-shaped ground electrode 150 because it blocks the plasma discharge port 111.

Next, one end of the ground terminal 151 is electrically connected to the ground electrode 150 and the other end is exposed to the outside of the discharge water reservoir 120 and can be grounded.

In addition, a hygrometer 160 and a thermometer (not shown) are provided inside the plasma housing 110 to properly control temperature and humidity to be described later.

Next, the temperature and humidity controller 200 will be described.

The temperature and humidity control unit 200 may include a water tank 210 for temperature and humidity control and a vaporization accelerating means 220.

The temperature and humidity control water storage tank 210 is formed in a container shape for accommodating water for vaporization, and can be detachably coupled to the lower surface of the plasma housing 110 .

Specifically, the water tank 210 for temperature and humidity control may include a base 211 for temperature and humidity control and a cover 212 for temperature and humidity control.

The base 211 for adjusting the temperature and humidity forms a container shape for accommodating water, and is provided with a point at the bottom where the evaporation accelerating means 220 and the temperature sensor 230 can be installed.

The cover 212 for temperature and humidity control may cover or open the upper surface of the base 211 for temperature and humidity control, and a steam outlet 213 is formed on the upper surface.

The steam outlet 213 is a passage through which steam vaporized therein can be discharged, and is formed in a position and size corresponding to the steam inlet 112 so as to communicate with the steam inlet 112 .

The vaporization accelerator 220 vaporizes the water in the temperature and humidity control water tank 210 to promote and induce steam generation.

The vaporization acceleration means 220 may be a heater that directly heats water, or may transfer heat indirectly using a medium.

In addition, the temperature sensor 230 may be installed submerged in water to detect the temperature of the water heated by the evaporation accelerating means 220 .

As another embodiment of the evaporation accelerating means 220, a natural evaporation body that induces natural evaporation of water through pores by mounting a hydrophilic porous material to the temperature and humidity control water storage tank 210 may be used. In this case, by insulating the temperature and humidity control water storage tank 210 using a separate heat insulating material, vaporization can be promoted by maintaining an appropriate temperature.

Another embodiment of the vaporization acceleration means 220 may be an ultrasonic vibrator that promotes vaporization by micronizing water into fine droplets by ultrasonic vibration.

Hereinafter, another embodiment of the present invention will be described with reference to FIG. 5 . 5 is a cross-sectional perspective view showing a plasma generating device including hydroxyl radicals according to another embodiment of the present invention.

Other embodiments of the present invention may also be composed of the plasma generating unit 100 and the temperature and humidity control unit 200, but the temperature and humidity control unit is as described above, so a description thereof will be omitted.

The plasma generating unit 100 may include a plasma housing 110, a discharge electrode 130, a discharge terminal 140, a ground electrode 150, and a ground terminal 151.

Another embodiment of the present invention may have a structure without the water storage tank for discharge.

Therefore, descriptions of the plasma housing 110, the ground electrode 150, and the ground terminal 151 are the same as those described above, and therefore, descriptions thereof will be omitted, and only the discharge electrode 130 and the discharge terminal 140 will be described.

The discharge electrode 130 is a means for generating plasma together with the ground electrode 150 and is vertically installed on the bottom of the plasma housing 110 .

The discharge electrode 130 may be formed in a sharp needle shape with a tapered upper end, and may have a columnar shape.

And, as shown in FIG. 4(a), the discharge electrode 130 may be made of only a general metal material, or may be made of a porous metal material having a plurality of pores formed therein. Even if a metal material is used, the possibility of arc furnace transition is minimized because a voltage lower than the voltage at which corona discharge occurs is applied.

The discharge terminal 140 is for applying a high voltage to the discharge electrode 130, and is connected to the discharge electrode 130 and extended to be exposed to the outside of the plasma housing 110 to apply a voltage. .

As shown in detail, it may be inserted into the discharge electrode 130 and connected in a buried state, but is not limited thereto.

Hereinafter, the operating state of the present invention will be described with reference to FIG. 6 . 6 shows an operating state diagram of the present invention.

The present invention is based on the atmospheric pressure low-temperature plasma generation principle, and stably generates a large amount of harmless hydroxyl radicals to the human body to effectively and quickly sterilize and remove contaminants including various microorganisms present in the space where humans live or the products used. It is a device that has

In other words, in order to solve the disadvantages of corona discharge, such as ozone generation, narrow processing area, and instability, a voltage corresponding to a low current dark discharge is applied to maintain an extremely low current and only some gases are ionized so that no light or sound is generated. It is possible to provide a plasma having an extremely low ozone concentration and no arc furnace transition.

To this end, while maintaining an extremely low current by applying a voltage corresponding to a dark discharge of a current lower than corona discharge to the discharge terminal 140, ionization sufficient to generate hydroxyl radicals without generating a discharge such as a streamer is going on

When a positive high voltage is applied, the discharge electrode 130 is charged (+), and as the air is ionized, electrons are accelerated to the discharge electrode 130 and ions are accelerated to the ground electrode 150.

At this time, only electrolytes such as calcium (Ca), potassium (K), and sodium (Na) included in the water are ionized to promote electron acceleration, and the water molecules remain in a non-ionized state.

This is because, when a voltage corresponding to dark protection of a current lower than corona discharge is applied, only electrolytes having a much stronger tendency to be ionized than water molecules are ionized, and water molecules are not ionized.

The ionized electrolytes are evenly dispersed in the pores of the discharge electrode 130 due to the capillarity of water, and contribute to generating plasma at the pointed portion.

Water serves as a carrier for transporting ions and also absorbs some of the ions and electrons to prevent excessive avalanches from occurring, thereby blocking the arc furnace transition.

Here, hydroxyl radicals can be generated in an electric field by supplying sufficient water vapor to the space where plasma is generated by discharge within the plasma housing 110, so that harmful substances such as ozone required for generating hydroxyl radicals are not required.

That is, since ozone is not generated in the present invention, a temperature and humidity environment for the composition of nanometer particle size water vapor can be provided in the present invention in order to increase the relatively small amount of hydroxyl radicals produced.

To this end, water vapor is generated in the temperature and humidity controller 200 and supplied to the plasma generator 100 .

As a result of the experiment, it was found that when the internal temperature of the plasma generating unit 100 is 15 to 35 ° C and the relative humidity is 50 to 80%, hydroxyl radicals capable of exhibiting 99.9% sterilization power are generated within a few minutes.

If the temperature is less than 15 ℃, the evaporation rate is slow and it is not enough to show 99.9% sterilization power. Going faster requires unnecessary humidity control. Even if the temperature range does not meet this, if it shows 99.9% sterilization power and there is no problem in terms of efficiency, it is okay to apply.

In addition, when the relative humidity is less than 50%, 99.9% sterilizing power cannot be guaranteed, and when it exceeds 80%, the generation rate of hydroxyl radical is too fast, and the stability of the plasma is lowered, causing an increase in current or ozone concentration. Even if the range of relative humidity does not meet this, it is irrelevant to apply it if it shows 99.9% sterilization power and there is no inefficiency problem.

To supply steam, the temperature and humidity control unit sets the water temperature to 40° C. or higher to promote vaporization and create humidification. The temperature sensor may sense the temperature of the water and maintain it at 40° C. or higher.

As described above, when a high voltage is applied in a state in which the optimum temperature and humidity are established, electrons and ions are accelerated to the discharge electrode 130 and the ground electrode 150, respectively. ), the ion wind is discharged toward the plasma discharge port 111 by passing through the surrounding empty space.

At this time, the hydroxyl radical moves along with the neutral gas, and the electrolyte contained in the water further increases the concentration of ions, so that it is possible to generate an ion wind strong enough to sufficiently deliver the hydroxyl radical to the sterilization target located outside.

Additionally, by installing a fan (not shown) having an appropriate wind speed above the ground electrode 150, the hydroxyl radical can be stably transferred farther.

Hereinafter, in order to derive the optimal temperature and humidity, an embodiment in which an experiment was conducted as follows is presented.

<Example 1>

Discharge electrode 130 is a discharge electrode (130) made of HDPE (High Density Polyethylene) having pores of 20 μm, a diameter of 5 mm, a height of 40 mm, an upper 10 mm sharp needle shape and a lower 30 mm cylindrical shape, and a tungsten wire having a diameter of 0.1 mm It was selected as the electrode (150).

In addition, as strains to confirm the degree of bactericidal activity, Gram-negative Escherichia coli 1 (self-cultivation, hereinafter E.coli1) and Gram-positive bacterium Methicillin resistance Staphylococcus aureus (NCCP 14754, National Pathogen Resource Bank, hereinafter MRSA) were selected and tested. performed.

After installing the discharge electrode 130 in the reservoir containing tap water, the ground electrode 150 was installed at an interval of 18 mm on the top. When the temperature of the plasma generation area (hereafter referred to as sheath) between the two electrodes is maintained at 25°C and the relative humidity is maintained at 30%, 40%, 50%, 60%, 70%, and 80% respectively, the discharge electrode When a positive high voltage of 9.5 kv was applied, the change in sterilization power was tested.

Attach the surface of the sample treated with bacteria of about 500 to 1000 CFU/25 cm2 at a distance of about 7 cm from the plasma housing of the present invention, operate the device for 15 minutes to generate plasma, and then use a 60 mm PCA (Plate count agar) rodac plate Observe the results after incubating the surface at 37℃ for 48 hours. The sample surface to which plasma was not applied after treatment with bacteria was used as a control. Figure 1 below is a photograph showing the sterilizing power according to the change in relative humidity.

<Figure 1>

As a result of the experiment, as the relative humidity of the sheath increased, the sterilizing power also increased. That is, the relative humidity and sterilization power were proportional.

The table below shows the results when the degree of sterilization was tested by maintaining the relative humidity in the range of 40 to 50% at 1% intervals under the same conditions as above.

humidity 40% 41% 42% 43% 44% 45% 46% 47% 48% 49% 50% MRSA 82.8% 85.1% 89.4% 90.1% 91.6% 95.4% 95.7% 98.6% 99.2% 99.8% 99.9%

Under the condition that MRSA is 99.9% or more sterilized, E.coli1 is the same, but under the condition that E.coli1 is sterilized by 99.9% or more, MRSA does not. Based on MRSA, which is relatively more difficult to sterilize because MRSA has a thicker cell wall than E.coli1, the relative humidity to exhibit 99.9% or more sterilization power at a temperature of 25 ° C was 50 to 80%.

<Example 2>

Under the same equipment conditions as <Example 1>, when the relative humidity of the sheath was maintained at 65% and the temperature was maintained at 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, and 35°C, respectively, discharge When a positive high voltage of 9.5 kv was applied to the electrode, the change in sterilizing power of MRSA was tested. Figure 2 below is a photograph showing the change in sterilization power according to temperature change.

<Figure 2>

As a result of the experiment, as the temperature of the sheath increased, the sterilizing power also increased. That is, temperature and sterilization power were proportional.

Under the same conditions, the change in bactericidal power of MRSA was tested when the temperature in the range of 10 ~ 15 ℃ was maintained at 1 ℃ intervals. Table 2 below is a table showing the change in sterilization power according to temperature change.

temperature 10℃ 11℃ 12℃ 13℃ 14℃ 15℃ MRSA 92.1 95.7 96.7 99.0 99.8 99.9

Here, the temperature for exhibiting the sterilizing power of 99.9% or more based on the relative humidity of the sheath of 65% was 15 to 35 ° C.

Under the same equipment conditions, sterilizing power and plasma stability were tested at the lowest temperature and humidity of 15 ° C and 50% and the highest temperature and humidity of 35 ° C and 80% among the temperature and humidity conditions of the sheath. Table 3 below is a table showing the sterilizing power and ozone concentration at the lowest temperature and humidity and the highest temperature and humidity.

temperature and humidity 15℃, 50% 35℃, 80% Bactericidal power (%) (MRSA) 99.9% 99.9% Ozone concentration (ppm) Less than 0.01ppm Less than 0.01ppm

As a result of the experiment, 99.9% or more sterilizing power was guaranteed at the lowest and highest temperature and humidity, and corona discharge stably occurred, so the temperature range in the sheath was 15 to 35 ° C and the relative humidity range was 50 to 80%.

<Example 3>

With the same conditions as in <Example 1>, under the temperature and humidity conditions of the sheath where 99.9% sterilization power is not guaranteed, the degree of sterilization power when the humidity is increased by artificially evaporating tap water in the temperature and humidity control water tank used as a discharge medium for the discharge electrode was experimented with.

Method 1) Ultrasonic: Install an ultrasonic vibrator in a water tank

Method 2) Heating: Heating the water in the water tank

Method 3) Natural vaporization method: Install hydrophilic porous fibers in the water tank

In addition, the following humidification conditions were set to confirm the effect of artificial humidification on sterilizing power at a sheath temperature of 20 ° C and a relative humidity of 40%.

Condition 1) No artificial humidification

Condition 2) Raise the relative humidity of the sheath to 60% by installing an ultrasonic vibrator in the water tank

Condition 3) Raise the relative humidity of the sheath to 65% by installing an ultrasonic vibration difference in the water tank

Condition 4) Heat the water in the reservoir (initial temperature 20℃) to 30℃ and maintain it

Condition 5) Heat the water in the reservoir (initial temperature 20℃) to 40℃ and maintain it

Condition 6) Heat the water in the reservoir (initial temperature 20℃) to 50℃ and maintain it

Condition 7) Heat the water in the reservoir (initial temperature 20℃) to 60℃ and maintain it

Condition 8) A porous resin (polyethylene) with a thickness of 2 mm, a height of 30 mm, and pores of 50 um was installed in the reservoir around the discharge electrode.

Condition 9) Install felt paper (Daewon Wood Board, Mini Felt T-53) with a thickness of 1 mm and a height of 30 mm around the discharge electrode in the water tank.

Figure 3 below is a photograph showing the results of the sterilization test under the above conditions.

<Figure 3>

As a result of the experiment, all three artificial humidification methods (Condition 2 ~ Condition 9) showed an effect in improving sterilization power.

Hereinafter, a plasma generating device including a hydroxyl radical according to another embodiment of the present invention will be described with reference to FIGS. 7 to 9 .

Other embodiments of the present invention may also be composed of the plasma generating unit 100 and the temperature and humidity controller 200. Since the temperature and humidity controller 200 has been described above, a description thereof will be omitted.

On the other hand, in various other embodiments of the present invention, there are main features of the discharge electrode 130 and the ground electrode 150.

As shown in FIG. 7 , both the discharge electrode 130 and the ground electrode 150 are made of a hydrophilic porous material, and the two electrodes may be disposed in parallel in a left-right direction.

Like the vertical needle-shaped discharge electrode 130, the ground electrode 150 may be exposed to the air while having a lower portion submerged in water in the grounding reservoir 170 and a sharp upper portion.

In addition, the grounding electrode 150 is added with a water reservoir 170 for grounding, and water including electrolyte may be used for current flow.

In addition, the grounding terminal 151 is connected to the water in the water storage tank 170 for grounding and serves as a grounding function as well as the discharge terminal 140.

The discharge electrode 130 and the ground electrode 150 may be arranged side by side so that when the two electrodes are arranged side by side in parallel, the upper needles are also facing upward.

In the embodiments of the present invention, a pair of discharging and grounding configurations are described, but by extension, more than one pair or a plurality of pairs may be configured.

During discharge, electron exchange is performed between the discharge electrode 130 and the ground electrode 150, pushing neutral gas toward the needle, that is, toward the plasma discharge port 111. At this time, with the generation of ion wind, radicals also move to the discharge port is emitted

Therefore, the direction of the plasma discharge port 111 in the up-and-down vertical arrangement and the left-right horizontal arrangement may be the same.

As such, the plasma generating unit 100 proposed by the present invention may further include a water storage tank 170 for grounding, which is installed upright so that the ground electrode 150 is exposed to the outside while accommodating water therein.

In addition, the grounding reservoir 170 has a ground fixing member 172 for accommodating water and fixing the grounding electrode 150 on the floor, and the grounding base 171 is covered and the grounding electrode 150 is at the center. It may include a grounding cover 173 through which a ground electrode hole 174 is formed, and a ground sealing member 175 inserted between the grounding base 171 and the grounding cover 173 to seal the ground. .

Referring to FIG. 8 , as another embodiment proposed by the present invention, the discharge electrode 130 and the ground electrode 150 may be made of a colloid containing an electrolyte in a porous resin without using water.

That is, both the discharge electrode 130 and the ground electrode 150 are made of a porous material and the two electrodes are arranged horizontally in parallel, but unlike the above-described embodiment, they do not contain water.

Therefore, the water reservoir 120 for discharge and the water reservoir 170 for grounding are not required.

As shown in FIG. 8, the discharge electrode 130 and the ground electrode 150 can be made into conductors by applying and fixing a colloid-like material including an electrolyte to a polymeric material such as porous resin (polyethylene, polypropylene). .

The colloid includes a hydrophilic material including an electrolyte, a hydrophobic material that can be smoothly fixed and maintained in a porous resin, and a surfactant to emulsify the same.

When such a colloidal formulation conductor is applied to a porous material, the electrolyte in the colloid evenly dispersed in the pores is ionically bonded with the polymer and fixed, thereby enabling the porous material to be a conductor.

The conductive porous electrode may be directly connected to the discharge terminal 140 and the ground terminal 151, or may be indirectly connected to the colloidal conductor and each terminal while the lower part of the electrode is included in the colloidal conductor.

That is, each of the discharge electrode 130 and the ground electrode 150 may be directly connected to the discharge terminal 140 and the ground terminal 151, or may be indirectly connected to each other.

In addition, each of the discharge electrode 130 and the ground electrode 150 may further include a colloidal conductor accommodating container.

Therefore, as shown in FIG. 9, the plasma generating unit 100 includes a first accommodating container 180a installed so that the discharge electrode 130 is exposed to the outside while containing the colloid, and the colloid while containing the colloid. A second accommodating container 180b upright to expose the ground electrode 150 to the outside may be further included.

In conclusion, the plasma generating device including hydroxyl radicals according to various embodiments of the present invention includes a plasma generating unit 100 generating plasma including hydroxyl radicals by high voltage discharge, and a lower part of the plasma generating unit 100. It is a device containing a hydroxyl radical composed of a temperature and humidity control unit 200 detachably coupled to and generating water vapor and supplying it to the plasma generating unit 100.

In addition, the plasma generating unit 100 has a plasma discharge port 111 for discharging plasma containing hydroxyl radicals formed on the top or side thereof, and a steam inlet port communicating with the temperature and humidity control unit 200 to allow water vapor to flow into the lower portion. Plasma housing 110 formed with 112, a discharge electrode 130 formed on one side of the plasma housing 110 with a pointed upper end, and a discharge terminal for applying a high voltage to the discharge electrode 130 from the outside 140, a ground electrode 150 formed on the other side of the plasma housing 110, and a ground terminal 151 electrically connected to the ground electrode 150 and exposed to the outside.

In addition, the plasma generating unit 100 further includes a water storage tank 120 for discharge, which accommodates water therein but is installed so that the discharge electrode 130 is exposed to the outside. The water storage tank 120 for discharge contains water. A fixing member 122 for accommodating and fixing the discharge electrode 130 to the bottom is formed and a discharge base 121 from which the discharge terminal 140 protrudes, covering the discharge base 121 and the discharge terminal 140 in the center. A discharge cover 123 in which a discharge electrode hole 124 through which the discharge electrode 130 passes is formed, and a sealing member 125 inserted between the discharge base 121 and the discharge cover 123 for sealing It can be made including.

In addition, the discharge electrode 130 is made of a hydrophilic porous material, and microdischarge may occur on the surface on which sharp needle-like pores are formed.

In addition, the discharge electrode 130 is composed of a first electrode body 131 made of a hydrophilic porous material and a second electrode body 132 made of a metal material and inserted into the center of the first electrode body 131. It can be.

In addition, the discharge electrode 130 may be a capillary body 133 in which a capillary 133a is formed in the center.

Also, the discharge electrode 130 may be made of a metal material.

In addition, the discharge electrode 130 is electrically connected to the discharge terminal connector 141 inserted between the plasma generator 100 and the temperature and humidity controller 200, and the discharge terminal connector 141 is connected to the discharge terminal bracket 142. ) can be fixed.

In addition, the internal temperature of the plasma generating unit 100 may be 15 to 35° C., and the relative humidity may be maintained at 50 to 80%.

In addition, a hygrometer 160 may be further included in the plasma housing 110 .

In addition, the ground electrode 150 may be formed in a linear or reticular shape so that plasma is well discharged through the plasma outlet 111 .

In addition, the ground electrode 150 may be arranged parallel to the discharge electrode 130 while forming a needle shape with a pointed top.

In addition, as shown in FIG. 7, the plasma generating unit 100 further includes a water storage tank 170 for grounding, which is installed so that the ground electrode 150 is exposed to the outside while accommodating water therein. In the reservoir 170, a ground fixing member 172 for accommodating water and fixing the ground electrode 150 is formed on the bottom, and the ground base 171 for grounding is covered and the ground electrode 150 passes through the center. It may include a grounding cover 173 in which an electrode hole 174 is formed and a ground sealing member 175 inserted between the grounding base 171 and the grounding cover 173 for sealing.

Also, as shown in FIG. 8 , the discharge electrode 130 and the ground electrode 150 may be conductive with a colloid containing an electrolyte in a porous resin.

In addition, as shown in FIG. 9, the plasma generating unit 100 includes a first accommodating container 180a installed so that the discharge electrode 130 is exposed to the outside while containing the colloid, and the colloid while containing the colloid. A second accommodating container 180b upright to expose the ground electrode 150 to the outside may be further included.

In addition, the temperature and humidity control unit 200 is detachably coupled to the lower surface of the plasma housing 110, and has a steam outlet 213 communicating with the steam inlet 112 at the top, and supplies water therein. It may include a temperature and humidity control water storage tank 210 and a vaporization accelerating means 220 introduced into the temperature and humidity control water tank 210 to promote water vaporization.

In addition, the water tank for temperature and humidity control 210 accommodates water and covers the base 211 for temperature and humidity control in which the vaporization accelerating means 220 and the temperature sensor 230 are installed, and the base 211 for temperature and humidity control and covers the water vapor outlet 213 may be formed of a cover 212 for adjusting temperature and humidity.

In addition, the vaporization acceleration means 220 may use any one of a heater for heating water, an ultrasonic vibrator for vaporization using ultrasonic vibration, and a natural vaporization body for spontaneous vaporization using a porous material.

In addition, when the vaporization accelerating means 220 is used as a heater, a temperature sensor 230 for sensing the temperature of the water heated by the heater may be further provided in the water storage tank 210 for adjusting the temperature and humidity.

Representative embodiments of the present invention have been described above with reference to the drawings, but those skilled in the art will be able to make various applications and modifications within the scope of the present invention based on the above information. Therefore, the scope of the present invention should not be limited to the described embodiments and should not be defined, and should be defined by not only the claims to be described later, but also those equivalent to these claims.

100: plasma generating unit
110: plasma housing 111: plasma discharge port
112: steam inlet 120: water tank for discharge
121: base for discharge 122: fixing member
123: discharge cover 124: discharge electrode hole
125: sealing member 130: discharge electrode
131: first electrode body 132: second electrode body
133: capillary body 133a: capillary
140: discharge terminal 141: discharge terminal connector
142: discharge terminal bracket 150: ground electrode
151: ground terminal 160: hygrometer
170: water tank for grounding
180a: first container 180b: second container
200: temperature and humidity control unit
210: water tank for temperature and humidity control 211: base for temperature and humidity control
212: cover for temperature and humidity control 213: steam outlet
220: vaporization acceleration means 230: temperature sensor

Claims (17)

A plasma generating unit that generates plasma containing hydroxyl radicals by discharge by high voltage, and a temperature and humidity control unit that is detachably coupled to the lower portion of the plasma generating unit and generates water vapor and supplies it to the plasma generating unit, including hydroxyl radicals. In the plasma generator,
The plasma generating unit,
a plasma housing having a plasma discharge port for discharging plasma containing hydroxyl radicals formed on the top or side thereof and a water vapor inlet port communicating with the temperature and humidity controller to allow water vapor to flow into the lower portion of the plasma housing;
a discharge electrode formed in a needle shape with a sharp upper end and formed on one side of the plasma housing;
a discharge terminal for applying a high voltage to the discharge electrode from the outside;
a ground electrode formed on the other side of the plasma housing; and
A plasma generator including a hydroxyl radical, characterized in that it comprises a; ground terminal electrically connected to the ground electrode and exposed to the outside. According to claim 1,
The plasma generating unit,
Further comprising a water storage tank for discharge that accommodates water therein but is installed so that the discharge electrode is exposed to the outside;
The first discharge reservoir,
A base for discharge having a fixing member for accommodating water and fixing the discharge electrode on the bottom and protruding the discharge terminal, and a discharge electrode hole covering the base for discharge and penetrating the discharge electrode in the center thereof. A plasma generating device including a hydroxyl radical, characterized in that it comprises a cover and a sealing member inserted between the discharge base and the discharge cover for sealing. According to claim 2,
The discharge electrode is
A plasma generator including hydroxyl radicals, characterized in that microdischarges occur on a surface made of a hydrophilic porous material and having sharp needle-like pores formed thereon. According to claim 2,
The discharge electrode is
A plasma generator including a hydroxyl radical, characterized in that it is composed of a first electrode body made of a hydrophilic porous material and a second electrode body made of a metal material and inserted into the center of the first electrode body. According to claim 2,
The discharge electrode is a plasma generator including a hydroxyl ring radical, characterized in that the capillary body formed in the center of the capillary. According to claim 1,
The discharge electrode is electrically connected to a discharge terminal connector inserted between the plasma generation unit and the temperature and humidity control unit, and the discharge terminal connector is fixed to a discharge terminal bracket. According to claim 1,
Plasma generator including hydroxyl radical, characterized in that the internal temperature of the plasma generating unit is 15 ~ 35 ℃, relative humidity is 50 ~ 80%. According to claim 1,
A plasma generating device including a hydroxyl radical, characterized in that a hygrometer is further included inside the plasma housing. According to claim 1,
The ground electrode is
A plasma generator including a hydroxyl radical, characterized in that it is formed in a linear or network shape so that the plasma is well discharged through the plasma outlet. According to claim 1,
The ground electrode is a plasma generator including a hydroxyl radical, characterized in that arranged side by side with a predetermined distance apart from the discharge electrode while forming a needle shape with a sharp upper end. According to claim 10,
The plasma generating unit,
Further comprising a storage tank for grounding, which accommodates water therein but is installed so that the ground electrode is exposed to the outside;
The grounding water tank,
A grounding cover having a grounding fixing member for accommodating water and fixing the grounding electrode on the floor, covering the grounding base, and having a grounding electrode hole formed in the center through which the grounding electrode passes, and the grounding base and the grounding Plasma generating device including a hydroxyl radical, characterized in that it comprises a ground sealing member inserted between the covers for sealing. According to claim 10,
The discharge electrode and the ground electrode are plasma generators containing hydroxyl radicals, characterized in that the porous resin is conductive with a colloid containing an electrolyte. According to claim 12,
The plasma generating unit,
a first accommodating container upright to expose the discharge electrode to the outside while containing the colloid; and
Plasma generator including a hydroxyl radical, characterized in that it further comprises; a second accommodating container built up so that the ground electrode is exposed to the outside while containing the colloid. According to claim 1,
The temperature and humidity control unit,
a storage tank detachably coupled to the lower surface of the plasma housing, having a water vapor outlet communicating with the steam inlet, and accommodating water therein; and
Plasma generator including hydroxyl radical, characterized in that it comprises a; vaporization accelerating means that is drawn into the inside of the temperature and humidity control reservoir to promote vaporization of water. 15. The method of claim 14,
The temperature and humidity control water tank,
A plasma generator including a hydroxyl radical, characterized in that it is composed of a temperature and humidity control base for accommodating water and in which the vaporization accelerator and temperature sensor are installed, and a temperature and humidity control cover covering the temperature and humidity control base and having the water vapor outlet formed thereon. 15. The method of claim 14,
The vaporization accelerating means,
A plasma generator including a hydroxyl radical, characterized in that any one of a heater for heating water, an ultrasonic vibrator for vaporization using ultrasonic vibration, and a natural vaporizer for spontaneous vaporization using a porous material can be used. 17. The method of claim 16,
When the vaporization accelerating means is used as a heater, a temperature sensor for sensing the temperature of the water heated by the heater is further provided in the temperature and humidity control reservoir.

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