KR20220060138A - Virus Sterilization Plasma Equipment for Applying Air Circulation Device - Google Patents

Abstract

The present invention relates to a plasma sterilization device applied to an air circulation device and, more specifically, to a plasma sterilization device applied to an air circulation device, which can be easily linked with an air conditioning system provided for purifying harmful pathogenic microorganisms within buildings such as hospitals, can provide discharge characteristics which are stable, uniform and highly dense, and can guarantee a sufficient residence time for harmful viruses within a plasma area, thereby increasing the virus treatment effect. To this end, the plasma sterilization device applied to an air circulation device according to the present invention is a plasma sterilization device installed at the pipe of an air circulation device, the plasma sterilization device comprising: a dielectric barrier filling layer reactor (10) which is installed between pipes (1) so as to inactivate harmful viruses in the treatment gas; an ozone removing filter (20) installed at the front side of the dielectric barrier filling layer reactor (10) in the pipes (1) so as to remove the ozone generated in the dielectric barrier filling layer reactor (10); an air blower (30) installed at the front side of the ozone removing filter (20) to transport the treatment gas treated in the dielectric barrier filling layer reactor (10); and a power supply device (40) provided to supply a high alternating current voltage to the dielectric barrier filling layer reactor (10).

Description

Plasma Sterilization Equipment for Applying Air Circulation Device

The present invention relates to a plasma sterilization device applied to an air circulation device, which is easily linked with an air conditioning system for purifying harmful pathogenic microorganisms in buildings such as hospitals, has stable, uniform, and high-density discharge characteristics, and prevents harmful viruses from plasma It relates to a plasma sterilization device applied to an air circulation device that can enhance the virus treatment effect by securing sufficient residence time in the area.

The air in a building can carry a variety of micro-organisms that are harmful to health, especially in hospitals. For this reason, the regulation of the air conditioning system for the treatment of airborne pathogenic microorganisms in hospitals is being applied more strictly than in general buildings.

It is known that more than 99.99% of fine dust and microorganisms suspended in indoor air are removed by a high-efficiency particulate arrestance filter (HEPA). However, these harmful microorganisms are trapped in the filter and are not deactivated, but are exposed to risks as they are, and the pressure loss is quite large due to the characteristics of the HEPA filter, so it has an economic problem in that the operating cost of the blower is high.

As a method to overcome this problem, interest in air purification using a low-temperature plasma (non-thermal plasma) has emerged. Low-temperature plasma has low energy consumption and excellent antimicrobial effect, so it is being applied to various fields. The main factors of the antibacterial effect of low-temperature plasma are UV radiation, local electric fields, reactive species (eg, O, O3, OH, NO, NO2), and charged particles. The most important point of the low-temperature plasma antibacterial effect compared to other methods is the synergistic effect in which the above-mentioned elements are all operated at the same time.

However, despite these advantages, when the low-temperature plasma method is applied to the treatment of airborne harmful microorganisms, it greatly contributes to the inactivation of various reactive species viruses mentioned above, but among them, ozone (O ₃ ) is harmful to the human body when exposed to the air. This may cause another problem. According to US EPA regulations, the concentration of ozone in the air is stipulated to be kept below 0.05 ppm. Therefore, technologies such as oxidation catalyst conversion, activated carbon adsorption, and high-temperature treatment are being applied to solve this problem.

On the other hand, when indoor air is polluted by odors, harmful gases, dust, or generated heat, which causes obstacles in human habitation, etc., removing the polluted air to the outside and replacing it with clean outdoor air is called ventilation. If not only the cleanliness of the indoor air but also the temperature and humidity and air flow distribution are considered, it belongs to the so-called air conditioning system (HVAC: Heating, Ventilating and Air Conditioning). Therefore, ventilation means only exchanging indoor polluted air with fresh outdoor air, and it is common not to consider indoor temperature and humidity or airflow. You must use an air purifier.

Air purification systems include UV-photocatalytic method, ozone generation method, filter treatment method, and low-temperature plasma ion generation method. Currently, the UV-photocatalyst system, which has a high market share, has little sterilization and deodorization effects, and there are UV safety issues, so the trend of facility reflection in the HVAC system is decreasing. It is difficult to maintain the market for ozone generating systems because there is a limiting concentration standard in the recommended indoor air quality standards. Although the filter treatment system constitutes the mainstream of air purifiers, in addition to the excellent advantages in terms of dust removal, the sterilization or reduction and removal performance of pathogenic bacteria and viruses is weak, and the maintenance cost is high due to frequent filter replacement. The low-temperature plasma ion generating system is expanding in all industries with the advantages of not only sterilizing microorganisms but also of excellent purification ability for gaseous particulate matter, maximizing oxygen ion generation and relatively minimizing ozone generation.

Atmospheric pressure low-temperature plasma generally has methods such as dielectric barrier discharge, corona discharge, arc discharge, glow discharge, and the like. Among them, the dielectric barrier discharge device has a configuration in which one side of a flat plate spaced at regular intervals and an electrode are covered with an insulator (=dielectric), and it is a discharge that occurs when an AC voltage is applied. As there is no sound between discharges like arc discharge or corona discharge, it is also called silent discharge. In particular, in the dielectric barrier discharge, when an insulator is used, a current cannot flow through the electrode as in the case of DC power, so that plasma is generated using alternating current (AC) power. For stable plasma generation, the gap between the electrodes is limited to several millimeters, and the plasma gas flows through the gap. Dielectric barrier discharge generates plasma by glow discharge while passing atmospheric air or a specific gas between the electrodes. When the current is cut off, plasma generation stops and active particles disappear immediately, so control is simple and leaves no residue. does not In addition, it can have various electrode structure shapes depending on the use, can generate plasma by mixing almost all kinds of gases, and the equipment is simple and can easily generate discharge. has the advantage of

As mentioned above, in order to treat harmful microorganisms and viruses by applying to the air circulation system, the dielectric barrier plasma discharge device, which is a low-temperature plasma method, is the optimal method, but the expansion and stability of the dielectric barrier discharge area with excellent economic efficiency and Securing safety through minimization remains a problematic technical task.

In order to solve the above problems, the present invention is easily linked with an air conditioning system for purifying harmful pathogenic microorganisms in buildings such as hospitals, has stable, uniform, and high-density discharge characteristics, and has sufficient retention of harmful viruses in the plasma region An object of the present invention is to provide a plasma sterilization device applied to an air circulation device capable of enhancing the virus treatment effect by securing time.

The plasma sterilizer applied to the air circulation device of the present invention is a plasma sterilizer installed in a pipe of the air circulation device,

The plasma sterilizer is installed between the pipe (1) and the pipe (1) and a dielectric barrier packed-bed reactor (10) for inactivating harmful viruses in the process gas;

an ozone removal filter 20 installed in front of the dielectric barrier packed bed reactor 10 in the pipe 1 to remove ozone generated in the dielectric barrier packed bed reactor 10;

a blower 30 installed in front of the ozone removal filter 20 to transport the processed gas treated in the dielectric barrier packed bed reactor 10;

It is characterized in that it is composed of a power supply device (40) for supplying an AC high voltage to the dielectric barrier packed bed reactor (10).

The present invention is easy to apply to an air conditioning system in a place exposed to harmful viruses such as hospitals, has an excellent virus sterilization effect, and can bring about a reduction in operating cost, and lower ozone, which is a problem in the plasma method, compared to the conventional method. There is an effect that can be removed by concentration and the plasma discharge can be stably maintained for a long time.

In addition, in the dielectric barrier packed-bed reactor, the plasma processing gas drifts due to the formation of mild plasma in the dielectric bed, unlike the conventional DBD charge-discharge type, in which the discharge characteristic in the filled dielectric bed is a problem due to the formation of a local strong electric field around the positive electrode. There is an effect that a wide area flowing uniformly without a channeling effect is formed.

In addition, the dielectric barrier packed-bed reactor has an advantageous structure to secure residence time in the dielectric bed in a state where mild plasma is evenly formed and contacts the process gas with high ion charge density and harmful viruses to be sterilized, so that the sterilization effect of the process gas is improved It has an excellent effect.

In addition, in the dielectric barrier packed-bed reactor, there is almost no region where a local strong electric field is formed in the dielectric bed, so a local strong electric field is formed. The amount of generation is also small, so it has the effect of being generated lower than the existing low-temperature plasma method.

1 is a configuration diagram of a plasma sterilizer applied to an air circulation device according to the present invention;
Figure 2 is a virus sterilization process diagram of the plasma sterilizer applied to the air circulation device according to the present invention
3 is a picture of the discharge characteristics of the plasma sterilizer applied to the air circulation device according to the present invention;
4 is a graph of ozone generation change according to voltage change of a plasma sterilizer applied to an air circulation device according to the present invention;
5 is an experimental graph of ozone generation according to a change in the flow rate of a processing gas of a plasma sterilizer applied to an air circulation device according to the present invention;

The plasma sterilizer applied to the air circulation device of the present invention is a plasma sterilizer installed in a pipe of the air circulation device,

The plasma sterilizer is installed between the pipe (1) and the pipe (1) and a dielectric barrier packed-bed reactor (10) for inactivating harmful viruses in the process gas;

an ozone removal filter 20 installed in front of the dielectric barrier packed bed reactor 10 in the pipe 1 to remove ozone generated in the dielectric barrier packed bed reactor 10;

a blower 30 installed in front of the ozone removal filter 20 to transport the processed gas treated in the dielectric barrier packed bed reactor 10;

It is characterized in that it is composed of a power supply device (40) for supplying an AC high voltage to the dielectric barrier packed bed reactor (10).

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

As shown in FIG. 1, the plasma sterilizer sterilizes harmful viruses in buildings such as hospitals in connection with the air conditioning system and supplies the sterilized clean process gas to the room with a dielectric barrier packed bed reactor 10 and , an ozone removal filter 20 , a blower 30 , and a power supply device 40 .

The dielectric barrier packed bed reactor 10 is a dielectric barrier pipe 11 on the outer surface between the pipe 1 and the pipe 1 spaced apart at regular intervals in a discharge method that generates atmospheric pressure low-temperature plasma by applying a high alternating current voltage. A negative electrode plate 12 in the form of a disk through which a negative electrode can flow is installed on the end surface of each pipe 1 spaced apart from each other by a predetermined distance inside the dielectric barrier tube 11, and the dielectric barrier tube 11 A positive electrode band 13 in the form of a band having a certain width through which the positive electrode can flow is installed on the outer surface of 11, and a dielectric bed 100 between two negative electrode plates 12 inside the dielectric barrier tube 11 ) is filled with a plurality of circular dielectric beads 14 , and a flow plug 15 is installed at the outer center of each negative electrode plate 12 .

Since the dielectric barrier tube 11 is a tube made of quartz and has stronger strength than glass, it is not easy to damage due to plasma energy while plasma is collected, and has good dielectric properties to easily induce plasma peak energy.

The negative electrode plate 12 and the positive electrode band 13 are configured to generate plasma by ionizing the processing gas flowing into the dielectric bed 100 by the high frequency power supplied from the power supply device 40, The negative electrode plate 12 is electrically connected to the power supply device 40, and is installed on the end surface of each pipe 1 in the form of a disk in the form of a disk with perforated holes 120 to smoothly flow in and out of the processing gas. It has a structure to support the dielectric beads 14 filled in the bed 100, and the positive electrode band 13 is electrically connected to the power supply 40 and is formed in the form of a band having a certain width of the dielectric barrier tube 11. It has a structure installed around the central part of the outer surface. Due to the installation structure of the negative electrode plate 12 and the positive electrode band 13, the plasma discharge generated in the dielectric bed 100 is not concentrated in a certain area and the dielectric bed 100 is Unlike the conventional DBD charging/discharging type, in which a local strong electric field is formed around the positive electrode, which causes a discharge characteristic to spread over the entire area, a mild plasma is formed in the dielectric bed 15. Plasma treatment gas It is possible to form a wide area that flows uniformly without channeling effect, thereby enhancing the sterilization effect generated by plasma discharge.

The dielectric beads 14 have a circular spherical shape and are filled in a plurality of the dielectric bed 100 to generate a stable electric potential by colliding with the process gas as it passes through, effectively removing various bacteria or various pathogenic microorganisms contained in the process gas, The dielectric bead 14 is filled between the two negative electrode plates 12 so that the plasma discharge is evenly and uniformly mild plasma is formed and active compared to the conventional DBD method, which is a problem of the amount of ozone generated in large amounts due to the local strong electric field around the discharge electrode. Make the chemical species uniform and abundant.

That is, as shown in FIG. 2 , when a processing gas containing harmful viruses is introduced into the dielectric bed 100 in which ions, electrons, RON, RNS, and UV radiation are generated in a complex manner by plasma discharge, the virus enters into the plasma decomposition mechanism. As a result, while staying in the dielectric bed 100 for a certain period of time, it is effectively decomposed and converted into a sterilized clean process gas and supplied to the room.

The flow plug 15 obstructs the flow of the processing gas to maintain a flow pattern of the processing gas and to secure a sufficient residence time of the processing gas in the dielectric bed 100 from the end surface of each pipe 1 toward the inside. It is installed in the form of a cylindrical block having a smaller diameter and a certain thickness than the negative electrode plate 12 at the center of the outer surface of each negative electrode plate 12.

That is, the flow plug 15 is installed on the outer surface of each negative electrode plate 12, which is the inlet and outlet of the dielectric bed 100, and the negative electrode plate 12 through which the processing gas of the negative electrode plate 12 is introduced and discharged. By blocking the space except around the edge of 3) The process gas stays in the dielectric bed 100 for a sufficient time, and the discharge occurs so that the form of the mild discharge is stably maintained, and the purified process gas is the same as the inlet by the flow plug 15 Since the fluid is disturbed when it is discharged in the shape of a donut, the ion density in the mild discharge region is increased.

The ozone removal filter 20 is installed inside the pipe 1 in the forward direction in which the clean process gas treated in the dielectric barrier packed bed reactor 10 is discharged, and a small amount generated in the dielectric barrier packed bed reactor 10 is installed. By removing the ozone of the clean process gas, it can be completely treated so that it does not affect the human body before being supplied to the room.

The ozone removal filter 20 is in the form of a honeycomb or particle with minimized pressure loss, and is composed of a filter containing an oxidation catalyst or activated carbon to enhance the ozone removal effect.

The blower 30 is installed in front of the ozone removal filter 20 and has a structure in which the number of rotations is variable so that the flow rate can be controlled by transferring the processing gas.

The power supply device 40 is a device for supplying AC high voltage to the negative electrode plate 12 and the positive electrode band 13 of the dielectric barrier packed bed reactor 10, and is a high voltage supply device capable of supplying 60Hz AC current.

Hereinafter, an experiment was conducted on a dielectric barrier packed-bed reactor, which is a core component of the plasma sterilization device applied to the air circulation device of the present invention.

1) Plasma discharge characteristics of dielectric barrier packed bed reactor (10)

When a high voltage alternating current is applied from the power supply unit 40 to the two negative electrode plates 12 and the positive electrode band 13 , the processing gas flowing into the dielectric bed 100 in the shape of a donut by the flow plug 15 is subjected to low temperature. A plasma discharge begins to form.

Thereafter, a discharge is continuously generated inside the dielectric bed 100 and the form of a mild discharge is stably maintained. And the final outlet has a structure in which the ion density of the mild discharge region is increased because the fluid is disturbed when the gas is discharged in the shape of a donut, just like the inlet.

As a result, the dielectric barrier packed-bed reactor 10 has a stable and uniform high-density discharge characteristic, and the harmful virus to be treated has a sufficient residence time in the plasma region, so that the virus treatment effect is enhanced.

2) Ozone generating characteristics

Ozone is a reactive oxygen species (ROS) in the plasma region and has an excellent sterilization effect. However, long-term exposure to ozone concentrations of 0.1 ppm or higher in the air can lead to respiratory, visual impairment, and mental illness. Therefore, in the United States, the concentration of ozone emitted from air purifiers is regulated to 0.05 ppm or less.

Unlike the conventional DBD reactor in which a large amount of ozone is generated due to the formation of a local strong electric field, the dielectric barrier packed bed reactor 10 proposed in the present invention is a mild type with high ion density and low ozone generation as mentioned in the plasma discharge characteristics described above. It is the type of structure in which the discharge occurs.

Hereinafter, in order to understand the generation characteristics of ozone, ozone generation characteristics for ozone generation according to voltage change and process gas flow rate change were identified.

Figure 4 shows the ozone generation change according to the voltage change. At this time, the process gas flow rate was fixed at 80 L/min and the power was changed to 0.35w-0.5w. As the voltage increased, the electric field strength increased and the amount of ozone generated increased. The concentration has a minimum value of 0.35w to 0.1ppm and a maximum value of 0.5w to 0.3ppm.

5 is a graph showing changes in ozone generation according to changes in the flow rate of processing gas. At this time, the power was fixed at 0.5w and the flow rate of the process gas was changed from 40L/min to 100L/min. At this time, as the flow rate of the processing gas was increased, the amount of ozone generated was decreased. Its concentration was 0.125 ppm when the flow rate was 40 L/min and 0.5 ppm when increased to 100 L/min.

As a result of the experiment in the above two cases, when the voltage was 80L/min and the power was 0.35w, the ozone concentration was 0.1ppm, showing the minimum value. Therefore, when it is linked with the ozone removal filter 20, it is possible to satisfy the emission standard condition of an American air purifier of 0.05 ppm or less.

Among the plasma sterilization devices of the present invention, the dielectric barrier packed bed reactor can be installed in a livestock ventilation system to prevent infectious diseases occurring in pig houses, barns, etc.

In addition, it is possible to flexibly cope with the sterilization effect and operating cost by combining the length of the filling width of the dielectric bed filled with dielectric beads of the dielectric barrier packed bed reactor, the applied voltage strength, the flow rate of the processing gas, and the modified shape according to the characteristics of the ozone removal filter. It has possible device characteristics.

As described above, in this specification and drawings, preferred embodiments of the present invention have been posted, and although specific terms are used, these are only used in a general sense to easily explain the technical content of the present invention and help the understanding of the present invention, It is not intended to limit the scope of the present invention. It will be apparent to those of ordinary skill in the art to which the present invention pertains that other modifications based on the technical spirit of the present invention can be implemented in addition to the embodiments disclosed herein.

1-Pube 10-Dielectric Barrier Packed Bed Reactor
11-dielectric barrier tube 12-negative electrode plate
13-positive electrode band 14-dielectric bead
15-Flowplug 20-Ozone Removal Filter
30 - blower 40 - power supply

Claims (4)

In the plasma sterilization device installed in the pipe of the air circulation device,
The plasma sterilizer is installed between the pipe (1) and the pipe (1), and a dielectric barrier packed-bed reactor (10) for inactivating harmful viruses in the process gas;
an ozone removal filter 20 installed in front of the dielectric barrier packed bed reactor 10 in the pipe 1 to remove ozone generated in the dielectric barrier packed bed reactor 10;
a blower 30 installed in front of the ozone removal filter 20 to transport the processed gas treated in the dielectric barrier packed bed reactor 10;
A plasma sterilizer applied to an air circulation device, characterized in that it comprises a power supply device (40) for supplying an AC high voltage to the dielectric barrier packed bed reactor (10). The method according to claim 1,
The dielectric barrier packed bed reactor 10 includes a quartz dielectric barrier pipe 11 that is installed surrounded by the outer surface between the pipe 1 and the pipe 1 spaced apart from each other, and a hole through which a processing gas can flow. A hole 120 is formed and the negative electrode plate 12 in the form of a disk is installed on the end face of each pipe 1 inside the dielectric barrier pipe 11, and is surrounded by the outer surface of the dielectric barrier pipe 11 Plasma applied to an air circulation device, characterized in that it consists of a positive electrode band (13) installed and having a certain width, and a circular dielectric bead (14) filled in the dielectric bed (100) between the negative electrode plate (12) sterilizer. The method according to claim 1,
Air circulation device, characterized in that the flow plug 15 in the form of a cylindrical block having a smaller diameter than the negative electrode plate 12 is installed in the center of the outer surface of each negative electrode plate 12 facing the inside of each pipe 1 Plasma sterilizer applied to The method according to claim 1,
The ozone removal filter 20 is a plasma sterilizer applied to an air circulation device, characterized in that it is a filter containing an oxidation catalyst or activated carbon.

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