JP2013031827A - Active species generator, air purifier, wastewater purifier and steam cleaner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active species generator, an air cleaner and a wastewater cleaner that can emit active species such as oxygen radical or hydroxy radical, these having disinfection action, into an indoor space, without generating even an insignificant dose of ozone or NOx that is harmful to the human body when discharging.SOLUTION: This active species generator includes a steam generating means that generates steam, a heating means that heats the generated steam and an electric discharge means that generates corona discharge between an electric discharge electrode and a counter electrode. In addition, it is characteristic that the internal steam pressure of the active species generator is higher than the external atmospheric pressure of the active species generator.

Description

  The present invention relates to an active species generator, an air cleaning device, a sewage purification device, and a steam cleaner that generate ions, active species, and the like by discharge to perform sterilization and the like.

In recent years, air purifiers have been widely used in order to keep the air in buildings and vehicles in a clean state at all times. The popular air purifying apparatus generates active species such as positive and negative ions and hydroxyl radicals (OH radicals or OH ^* ) from water vapor in the air by causing discharge in the air.

When discharged in the normal air, nitrogen ions (N ₂ ⁺ , N ₂ ⁻ ), oxygen ions (O ₂ ⁻ , O ₂ ⁺ , O ⁻ , O ⁺ ), nitrogen radicals (N ^* ), oxygen It is known that substances such as radicals (O ^* ) are generated at the same time. The generated radicals immediately bind to nearby air molecules. For example, in the discharge in air, when oxygen radicals are generated by the reaction O ₂ → 2O ^* , if they come into contact with oxygen molecules, a reaction O ^* + O ₂ → O ₃ occurs and ozone harmful to the human body is generated. . Similarly, when N ^* is generated by a reaction of N ₂ → 2N ^* , malodorous components are removed by reactions such as N ^* + O ₂ → NO ₂ , N ^* + O ^* → NO, and N + O ^* + O ^* → NO _2. NOx possessed is generated. As described above, there is a problem that ozone and NOx are easily generated in the air. In addition, if the concentration of desired active species or the like is increased by increasing the applied voltage, the concentration of ozone and NOx also increases. Therefore, in order to increase the concentration of desired ions, active species, etc. while suppressing the generation of ozone and NOx due to discharge, means for generating water vapor and causing discharge in the water vapor have been studied.

  For example, Patent Document 1 relates to a static eliminator that suppresses ozone and malodorous components generated by discharge, and FIG. 12 shows a side view of the configuration of the static eliminator. This static eliminator has an air generator 81 that blows out high-pressure air into water and contains water in a cluster state, and produces air with a humidity of around 100%, and an air passage 82 connected to the air generator 81. Provided. In the air passage 82, a heater 85 for heating the air and a high-voltage discharge electrode 86 for monopolar charging the cluster in the air are provided between the heater 85 and the opening 83. The part 83 is directed to the workpiece 84.

  Patent Document 1 describes that the presence of ozone in the vicinity of the high-pressure discharge electrode 86 can suppress the generation of ozone. Moreover, it describes that it is suitable for static elimination in a clean room with few dust particles because it uses a cluster of pure water.

  Patent Document 2 and Non-Patent Document 1 relate to a plasma sterilization apparatus capable of generating a plasma flow in an atmospheric water vapor flow and sterilizing the plasma flow. As shown in FIG. 13, this sterilization apparatus is made of a dielectric and one end is opened to the atmosphere, and a sterilization target to be sterilized is placed inside a pipe 91 and the other end of the pipe 91, A water vapor generating unit 92 that generates water vapor to be circulated into the tube 91 and a discharge unit 93 provided in the middle of the tube 91 and causing dielectric barrier discharge inside the tube 91 are provided. According to this configuration, it is described that the water vapor in the tube 91 is converted into plasma under atmospheric pressure by dielectric barrier discharge and can be sterilized by the plasma flow of water vapor.

Japanese Patent Laid-Open No. 9-115683 (published on May 2, 1997) JP 2009-22391 A (published February 5, 2009)

Takehiko Sato, Go Koi, Proceedings of the Japan Society of Mechanical Engineers Fluid Engineering Division, G605 (2010)

However, since the technique shown in Patent Document 1 is a technique that creates air with a humidity of around 100% containing water in a cluster state by jetting high-pressure air into a water tank, oxygen and nitrogen are contained in the air. It is a premise to include. Therefore, nitrogen radicals and oxygen radicals are generated by discharge with a high voltage, and as a result, the technique disclosed in Document 1 has a problem that ozone and NOx cannot be reduced sufficiently. Furthermore, since the technique shown in Patent Document 1 includes air, hydroxyl radicals are less likely to be generated with the same electric power as compared with the case of 100% water vapor. For example, when a negative voltage is applied to the discharge electrode in a state containing air, an electron attachment reaction of O ₂ + e− → O ₂ ⁻ occurs. Since the energy required for this reaction is 0.36 eV, if even a small amount of air is included, more ions are generated before the active species are generated. For this reason, the static eliminator may be effective, but if it tries to generate a large amount of active species such as hydroxyl radicals, the power consumption increases as compared with the case of 100% water vapor. In addition, since the temperature for warming the ventilation path is as low as 30 to 90 ° C., water vapor is condensed on the discharge electrode, and there is a possibility that the discharge may not be performed.

  In the techniques shown in Patent Document 2 and Non-Patent Document 1, the plasma region can be enlarged by dielectric barrier discharge, and many active species are generated in the pipeline. However, since a dielectric is interposed between the discharge electrode and the counter electrode, it is necessary to set a large applied voltage. For this reason, an expensive power supply is required and cannot be widely spread. Furthermore, in the dielectric barrier discharge, it is necessary to apply a certain frequency in order to decompose the raw material gas, and electromagnetic waves are generated. Such a sterilization apparatus is used in a medical field or the like, but there is a possibility that an electromagnetic wave may lead to a malfunction of the medical device. In addition, there is a problem that the object to be sterilized needs to be present in the pipeline, and the sterilization space is narrow.

  Therefore, the present invention has been made in view of such problems, and its purpose is to generate active species such as oxygen radicals and hydroxyl radicals having a sterilizing action without generating ozone or NOx. It is to realize a general-purpose device.

  An active species generating apparatus according to the present invention includes a water vapor generating unit that generates water vapor, a heating unit that heats the generated water vapor, and a discharge unit that generates corona discharge between the discharge electrode and the counter electrode. The inside of the generator is characterized in that the water vapor pressure is higher than the atmospheric pressure outside the active species generator.

  The active species generator according to the present invention further includes a first active species generator that applies a positive voltage to the discharge electrode and a second active species generator that applies a negative voltage to the discharge electrode. And the second active species generator includes a water vapor generating means for generating water vapor, a heating means for heating the generated water vapor, and a discharge means for generating a corona discharge between the discharge electrode and the counter electrode. The interior of the second active species generator is characterized in that the water vapor pressure is higher than the atmospheric pressure outside the first and second active species generators.

  The active species generator may be used for an air purifier, a sewage purifier, or a steam cleaner.

  According to the present invention, the inside of the discharge part is filled with substantially 100% water vapor, so that oxygen radicals and hydroxyl radicals having a sterilizing action are generated without generating ozone or NOx harmful to the human body at the time of discharge. It becomes possible to discharge | release active species, such as to indoor space.

1 is a cross-sectional view illustrating a configuration example of an active species generator in Example 1. FIG. 1 is a perspective view showing an example of the configuration of an active species generator in Example 1. FIG. FIG. 5 is a cross-sectional view showing a configuration example of an active species generator in Example 2. FIG. 6 is a cross-sectional view showing a configuration example of an active species generator in Example 3. FIG. 6 is a cross-sectional view showing a configuration example of an active species generator in Example 4. It is the perspective view which showed the structural example of the active species generator in Example 4. FIG. FIG. 10 is a cross-sectional view showing a configuration example of an active species generator in Example 5. It is the graph which showed the production | generation of hydrogen peroxide by the active species generator of this invention. It is the perspective view which showed the measuring apparatus in Example 6. FIG. It is the perspective view which showed the structural example of the sewage purification apparatus in Example 7. FIG. FIG. 10 is a perspective view illustrating a configuration example of a steam cleaner according to an eighth embodiment. It is a side view of the structure of the static elimination apparatus which concerns on patent document 1. It is a block diagram of the sterilizer based on patent document 2. FIG.

  The present invention generates corona discharge inside an active species generator that is almost free of air and filled with water vapor, so that ozone and NOx are hardly generated, and oxygen radicals and hydroxyl radicals having a sterilizing action are generated. It is characterized by generating active species, and the mechanism is described below.

Since only H ₂ O exists in water vapor, when a positive voltage is applied and discharged,
H ₂ O → H ⁺ + OH ^* + e −
By the above reaction, hydrogen ions and hydroxyl radicals are generated. Further, when hydrogen ions are neutralized by giving electrons, hydrogen radicals are generated. Hydroxyl radicals are known to have high activity and are used not only for sterilization but also for oxidizing various materials.

Next, when the generated hydrogen radical further reacts with water,
H ^* + H ₂ O → H ₂ + OH ^* (1)
By this reaction, a hydroxyl radical having a strong oxidizing action is generated. In addition, when bonded with the generated hydroxyl radicals,
OH ^* + OH ^* → O ^* + H ₂ O (2)
Oxygen radicals are generated by this reaction. This oxygen radical also has a strong oxidizing action and a sterilizing action.

On the other hand, when a negative voltage is applied and discharged,
H ₂ O + e ⁻ → OH ⁻ + H ^* (3)
By this reaction, hydroxide ions and hydrogen radicals are generated. The reaction in which hydroxyl radicals and oxygen radicals having a sterilizing action are generated from hydrogen radicals is as shown in formula (1).
OH ⁻ → OH ^* + e−
By this reaction, a hydroxyl radical having a sterilizing action is generated.

Thus, by generating corona discharge in water vapor, hydroxyl radicals and oxygen radicals having a sterilizing action can be generated. Since the hydroxyl radicals thus generated are highly reactive, some hydroxyl radicals do not become oxygen radicals via the reaction of (2),
OH ^* + OH ^* → H ₂ O ₂ (4)
The reaction changes to hydrogen peroxide. It reacts with water molecules,
OH ^* + H ₂ O → H ₂ O ₂ + H ^* (5)
This also changes to hydrogen peroxide. Hydrogen peroxide has a lower sterilization effect than hydroxyl radicals and oxygen radicals, but can be present longer than hydroxyl radicals and oxygen radicals because it is relatively stable.

Furthermore, hydrogen peroxide reacts with negative ions such as H ₂ O ⁻ and OH ⁻ generated by discharge together with the active species, so that H ₂ O ₂ + H ₂ O ⁻ → OH ^* + OH ⁻ + H ₂ O. (6)
H ₂ O ₂ + OH ⁻ + H ^* → OH ^* + OH ⁻ + H ₂ O (7)
Hydroxyl radicals can be generated again by the above reaction. Whether the reactions of the formulas (6) and (7) can occur was estimated using the quantum mechanics first-principles molecular dynamics method. When the total energy of the substance on the left side is subtracted from the total energy of the substance on the right side, the difference value is -1.48 eV in the case of equation (6) and -3.03 eV in the case of equation (7). . That is, it is considered that both reactions of the formulas (6) and (7) generate heat and stabilize when changing from the substance on the left side to the substance on the right side, and H ₂ O ₂ is replaced with H ₂ O ⁻ or OH ^−. It is thought that hydroxyl radicals are easily generated by the action of negative ions.

The reason that ozone is hardly generated is that the reaction path until ozone is generated from a substance generated when discharged in water vapor becomes complicated. For example, when considering a reaction in which ozone is most likely to be generated from hydroxyl radicals generated by discharge with a positive voltage, first, the reaction of formula (2) by hydroxyl radicals occurs to generate oxygen radicals. If an oxygen radical reacts with another oxygen radical,
2O ^* → O ₂ (8)
Oxygen molecules are generated by this reaction. Furthermore, the generated oxygen molecules react with oxygen radicals generated in another process,
O ^* + O ₂ → O ₃ (9)
Ozone is generated for the first time. Therefore, unlike in air, it is necessary to go through a reaction with low probability several times in water vapor. That is, by performing discharge within approximately 100% of water vapor, which has a much lower proportion of oxygen molecules than the atmosphere, the probability of ozone generation is greatly reduced, and ozone can be reduced.

Similarly, when considering a reaction in which ozone is most likely to be generated from hydrogen radicals generated by discharge with a negative voltage,
H ^* + H ₂ O → OH ^* + H ₂ (10)
Since ozone is generated from the hydroxyl radical generated by the reaction by the reactions of formulas (2), (8), and (9), the probability of ozone generation is greatly reduced. Further, NOx is not generated if water vapor is 100% because nitrogen does not exist.

  As described above, by discharging in water vapor without nitrogen and oxygen, active species such as oxygen radicals, hydroxyl radicals, and hydrogen radicals can be generated with little generation of ozone and NOx. Hydroxyl radicals and oxygen radicals have a strong oxidizing power and can disinfect bacteria and molds and decompose organic compounds and odors. Further, since the hydrogen radical has a strong reducing power, a hydroxyl radical can be generated by the reaction of formula (10), and the same action can be exhibited. Furthermore, if it is in water vapor | steam, it will be thought that a part of hydroxyl radical with high reactivity will change into hydrogen peroxide, but it can return to a hydroxy radical again by couple | bonding with a negative ion after that. Therefore, not only the discharge space but also a hydroxyl radical having a high sterilizing power can be applied over a wide range.

  An embodiment for realizing the above mechanism will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view of an active species generator according to Embodiment 1, and FIG. 2 is a perspective view of the device. This active species generator is composed of an evaporation unit 1, a water vapor passage unit 2, and a discharge unit 3. First, the evaporation part 1 is comprised from the container 4, and has the water 5 in the inside. The water 5 is heated by the first heating means 6 as a water vapor generating means arranged at the lower part of the container 4 and is changed into water vapor. The generated water vapor is conveyed to the discharge unit 3 via the water vapor passage unit 2 connected to the container 4. The water vapor passage portion 2 has a hollow structure and is made of a material that easily conducts heat.

  The discharge part 3 is surrounded by the counter electrode 9 and the opening part 11, and the discharge electrode 8 is disposed therein. The discharge electrode 8 is made of a wire-like metal, to which the voltage application device 10 is connected, and the counter electrode 9 is made of a metal and is grounded. The opening 11 may be open or may be surrounded by a mesh-like metal wire or the like that is electrically connected to the counter electrode 9, but it is more preferable that the opening 11 is open.

  The water vapor generated in the evaporation unit 1 is transported to the discharge unit 3, but in order to prevent air from being present near the discharge electrode 8, air is prevented from flowing into the apparatus from the opening 11. The water vapor pressure inside the active species generator needs to be higher than the external atmospheric pressure. For example, if the external atmospheric pressure is 1 atm, the water vapor pressure can be increased to 1014 hPa and the atmospheric pressure can be 1 atm or higher if the inside of the active species generator is 99.8 ° C. or higher. That is, if the evaporation part 1, the water vapor passage part 2, and the discharge part 3 are heated by the second heating means 12, and the inside of the apparatus is set to 99.8 ° C. or more, the water vapor is released from the opening part 11, Air is prevented from flowing into the apparatus from the opening 11. The second heating means 12 may be wound around the apparatus with, for example, a ribbon-like heater in order to heat the entire apparatus.

  At this time, by setting the water vapor pressure inside the active species generator to an external pressure or higher, the inside of the active species generator is in a state where the water vapor concentration is almost 100%, and oxygen and nitrogen are almost present in the discharge part 3. Disappear. In this configuration, when a positive or negative voltage is applied to the discharge electrode 8 to generate a corona discharge with the counter electrode 9, oxygen radicals and hydroxyl groups having a sterilizing action are generated without generating ozone and NOx. Generates active species such as radicals. The absolute value of the voltage applied to the discharge electrode 8 is preferably 1 kV to 10 kV. In the case of 1 kV or less, the distance between the discharge electrode 8 and the counter electrode 9 needs to be 2 mm or less, and there is a risk that dust or the like will adhere between these electrodes due to static electricity, resulting in electric leakage. This is because there is a possibility that a safety problem of the apparatus may occur. In order to generate many active species at a low voltage, a DC voltage is preferable. In this case, since it does not adversely affect other medical devices and the like due to electromagnetic waves, it can be used at medical sites. The generated active species are released into the indoor space through the opening 11 by the pressure generated by the generation of water vapor.

  In order to prevent the condensation of water vapor in the discharge part 3, it is desirable to keep the inside of the discharge part 3 at 100 ° C. or higher by the second heating means 12. If condensation occurs, arc discharge or creeping discharge occurs between the discharge electrode 8 and the counter electrode 9, and there is a risk that the apparatus will break down. In addition, a leakage current flows between the electrodes through water droplets generated by condensation, and there is a possibility that discharge will not occur.

  FIG. 3 is a configuration diagram of an active species generator according to the second embodiment, in which two active species generators according to the first embodiment are arranged. The first active species generator includes a discharge electrode 8 and a counter electrode 9 in the discharge unit, and the second active species generator includes a discharge electrode 13 and a counter electrode 14 in the discharge unit. Each of the active species generators includes a container having water, similar to the active species generator of Example 1, and the water is heated by the first heating means disposed at the lower part of the container to change into water vapor. It is done. The generated water vapor reaches the discharge part, and makes the discharge part have a water vapor pressure higher than the external atmospheric pressure. At this time, by setting the water vapor pressure inside the active species generating apparatus including the discharge part to be equal to or higher than the external atmospheric pressure, the inside of the active species generating apparatus is in a state where the water vapor concentration is almost 100%. Almost disappears. In the discharge section in this state, a positive voltage is applied to the discharge electrode 8 of the first active species generator and discharged between the counter electrode 9 and a negative voltage is applied to the discharge electrode 13 of the second active species generator. Applied and discharged between the counter electrode 14. With these configurations, the first active species generator generates positive ions and the second active species generator generates negative ions together with active species such as oxygen radicals and hydroxyl radicals having a sterilizing action. The generated active species and positive and negative ions are released into the indoor space through the opening 11 by the pressure generated by the generation of water vapor. In order to generate many active species at a low voltage, a DC voltage is preferable.

Here, when a negative voltage is applied and discharged, hydroxide ions and hydrogen radicals are generated by the reaction of formula (3). When the total energy of hydroxide ions and hydrogen radicals is compared with the energy of H ₂ O ^{− by} the quantum mechanics first-principles molecular dynamics method, H ₂ O ⁻ is lower by 1.559 eV, It is considered a stable substance. Therefore, the generated hydroxide ions and hydrogen radicals collide again,
H ^* + OH ⁻ → H ₂ O ⁻ (11)
H ₂ O ⁻ is generated by this reaction, and further H ₂ O ⁻ reacts with hydrogen ions, so that H ⁺ + H ₂ O ⁻ → H ^* + H ₂ O (12)
As a result, hydrogen radicals are generated again. When this hydrogen radical reacts with a water molecule, a hydroxyl radical can be generated by the reaction of formula (10).

  Since the hydroxyl radical is highly reactive, it is said that it changes into another substance in a very short time, but according to this method, a hydroxyl radical can be generated within the reach of ions. Therefore, unlike the sterilization method by discharge between a pair of discharge electrodes and counter electrodes as in the first embodiment, ions spread in the room space, so that the space that can be sterilized is expanded.

FIG. 4 is a configuration diagram of the active species generating apparatus according to the third embodiment, and includes an active species generating apparatus according to the first embodiment and an electron generating device 15 in the vicinity of the opening 11 thereof. The electron generating device 15 is made of an electric wire having a large electric resistance, emits thermoelectrons at a high temperature, and the emitted electrons react with hydrogen ions emitted from the opening 11,
H ⁺ + e ⁻ → H ^*
This generates hydrogen radicals. When this hydrogen radical reacts with a water molecule, a hydroxyl radical is generated by the reaction of formula (10), and the sterilization efficiency can be increased.

  FIG. 5 is a configuration diagram of the active species generating apparatus according to the fourth embodiment, in which a soot electrode 16 is disposed between the discharge electrode 8 and the counter electrode 9 of the active species generating apparatus of the first embodiment. FIG. 6 is a perspective view of the discharge part of the apparatus, showing a transparent state. The soot electrode 16 is disposed so as to surround the wire-shaped discharge electrode 8, and the counter electrode 9 is further disposed so as to surround the soot electrode 16. The discharge electrode 8 is connected to the voltage application device 10 and is applied with a positive or negative voltage so that a discharge occurs between the discharge electrode 8 and the counter electrode 9. Further, the saddle electrode 16 is connected to a voltage application device 17 and is applied with a voltage of several V to several hundred V having the same polarity as the voltage applied to the discharge electrode 8.

  According to this configuration, since the electric field in the discharge part 3 is directed from the discharge electrode 8 toward the soot electrode 16, ions generated from the discharge electrode 8 face the soot electrode 16 and are grounded. Touch and disappear. Thus, by arranging an electrode to which a low voltage having the same polarity as the voltage applied to the discharge electrode 8 is disposed between the discharge electrode 8 and the counter electrode 9, a desired radical can be efficiently released. . In the present embodiment, the voltage applying device 17 is connected to the saddle electrode 16, but a resistor may be provided between the saddle electrode 16 and the ground instead.

  FIG. 7 is a configuration diagram of the active species generating apparatus according to the fifth embodiment, in which the evaporation section 1, the water vapor passage section 2, and the discharge section 3 of the active species generating apparatus of the first embodiment are combined into one. The inside of the apparatus is composed of water 5, a discharge electrode 8, and a counter electrode 9. The discharge electrode 8 is covered with an insulator 18 except for the vicinity of the tip so as not to touch the water 5, and the tip is located near the water surface. Be placed. The counter electrode 9 is disposed near the tip of the discharge electrode 8 and is grounded. In this configuration, the water 5 is evaporated by the first heating means, and discharge is generated in the water vapor. At this time, it becomes easy to prevent inflow into the air by providing the discharge part in the vicinity of the water surface. Further, the apparatus can be reduced in size by eliminating the water vapor passage.

  Example 6 describes an active species generator that generates negative ions together with active species such as hydroxyl radicals and hydrogen peroxide. In the first embodiment, the voltage applied to the discharge electrode 8 is a positive or negative voltage. However, the sixth embodiment is different from the first embodiment in that the negative voltage is applied to the discharge electrode 8. Details of the sixth embodiment will be described below.

  Hydroxyl radicals generated by the active species generator of this example are highly reactive and can decompose bacteria and the like, but easily react with other substances. In water vapor, it is changed to hydrogen peroxide by the formulas (4) and (5). The hydrogen peroxide produced here has a weak sterilization effect as compared with hydroxyl radicals, but has high stability, and therefore can exist for a long time and has little influence on the human body. Moreover, when hydrogen peroxide reacts with negative ions, it generates hydroxyl radicals as shown in formulas (6) and (7). For this reason, hydroxyl radicals can be generated and sterilized if hydrogen peroxide and negative ions are present, even if not near the discharge.

In Example 6, the voltage V1 applied to the discharge electrode 8 of the active species generator of FIG. 1 is lower than the voltage V2 applied to the counter electrode 9, and the voltage applied to the counter electrode 9 in Example 6 to use the above reaction. V2 is 0 V or less (V1 <V2 ≦ 0). When discharge is caused in the discharge part 3 using this condition, hydroxide ions and negatively charged water molecules H ₂ O ⁻ are also generated together with various active species and released into the indoor space. These negative ions cause the reaction of hydrogen peroxide generated by the formulas (4) and (5) and the formulas (6) and (7) to generate hydroxyl radicals.

  Here, an experiment for demonstrating the above phenomenon will be described. First, in the active species generator of FIG. 1 according to Example 1, when hydroxyl radicals are generated in water vapor, the concentration of hydrogen peroxide that is considered to be generated via the reactions of formulas (4) and (5) An experiment was conducted to confirm this. The discharge electrode 8 is applied with a positive or negative voltage to cause discharge, and the hydrogen peroxide concentration contained in the liquid condensed from the gas that has passed through the discharge portion is determined as a hydrogen peroxide concentration test reagent (pack test WAK-H2O2, stock Evaluation was made by Kyoritsu Corporation. FIG. 8 shows the experimental results. From this experiment, almost the same amount of hydrogen peroxide was generated at the positive voltage and the negative voltage, and the hydrogen peroxide concentration was increased in proportion to the applied power.

  Next, an experiment was conducted to verify the strength of the sterilization effect when negative ions were generated simultaneously. FIG. 9 is a schematic diagram of the measuring apparatus used in the experiment, and has the same structure as that of the active species generator of Example 1 except that the shape of the water vapor passage section 2 is changed. The indigo carmine aqueous solution 30 is arranged at the tip of the above. The indigo carmine aqueous solution 30 has a deep blue color, but is decomposed and decolorized by reaction with active species such as hydroxyl radicals, oxygen radicals, and hydrogen peroxide. Using this property, the strength of the sterilization action was verified.

  First, an experiment was conducted to compare the degree of decolorization of the indigo carmine aqueous solution 30 when a positive voltage or a negative voltage was applied to the discharge electrode 8. In the case of positive voltage, +7.8 kV is applied to the discharge electrode 8 and the counter electrode 9 is grounded. In the case of negative voltage, −7.9 kV is applied to the discharge electrode 8 and the counter electrode 9 is grounded. Time discharge was performed. At this time, the electric power is 3.8 W in both positive and negative directions.

  As a result of the measurement, the indigo carmine aqueous solution 30 was decolorized earlier when a negative voltage was applied than when a positive voltage was applied. This indicates that the sterilization effect is stronger when a negative voltage is applied. It is thought that this is because, by applying a negative voltage and generating negative ions, more hydroxyl radicals having a strong sterilizing action can be generated by the reactions of formulas (6) and (7) than when a positive voltage is applied.

  Next, in the active species generator that applies a negative voltage to the discharge electrode 8, the degree of decolorization of the indigo carmine aqueous solution 30 is determined for the case where the opening 11 is opened and the case surrounded by a mesh-like metal wire. A comparative experiment was performed. In this experiment, −7.9 kV was applied to the discharge electrode 8, the counter electrode 9 and the mesh-shaped metal wire were grounded, and discharge was performed for 1 hour.

  As a result of the measurement, the indigo carmine aqueous solution 30 was decolorized in the open case compared to the case surrounded by the mesh-like metal wire. This indicates that the sterilization effect is stronger when the opening 11 is opened. When the opening 11 is opened, the generated active species and negative ions are efficiently released. On the other hand, when the opening 11 is surrounded by a grounded metal wire, the negative ions are Since the Coulomb force attracts the metal wire and deprives the electrons, the rate at which negative ions are released decreases. For this reason, it is considered that negative ions can be released more efficiently and more hydroxyl radicals having a strong sterilizing action can be generated when they are open.

  From the above two experimental results, it was found that the sterilization action can be enhanced by releasing negative ions together with active species such as hydroxyl radical and oxygen radical. Furthermore, negative ions and hydrogen peroxide are more stable than unstable hydroxyl radicals. For this reason, hydroxyl radicals can be generated and sterilized by allowing negative ions to act even at locations away from the active species generator. Thus, conventionally, only the vicinity of the active species generating device could be sterilized, but it becomes possible to sterilize a distant object. At this time, for example, if an object or a portion to be sterilized is set to zero potential or positive potential, negative ions are directed there, so that the sterilization action can be improved.

  FIG. 10 is a configuration diagram of a sewage purification apparatus equipped with an active species generator according to the present invention. FIG. 10A shows the same structure as that of the active species generator of Example 1, except that the shape of the water vapor passage 2 is changed so that the opening from which the active species are discharged faces the sewage 20. It has become. FIG. 10B shows an active species passage portion 21 provided at the tip of the opening of the active species generator of Example 1, and one end of the active species passage portion 21 is disposed in the sewage 20. . Furthermore, in order to stop the 2nd heating means 12 and to prevent the backflow of sewage which occurs when the pressure in the active species generator decreases, the first valve 22 for sending air into the device and the generation of active species A second valve 23 is provided for releasing air remaining in the apparatus to the outside when the apparatus starts operation. Since the sewage purification apparatus of FIG. 10B directly releases the active species into the sewage, an efficient purification effect can be brought about.

  Moreover, the sewage here means water containing various bacteria, organic substances, metals and the like. As for various germs and organic matter, the germs and organic matter are decomposed by releasing the generated hydrogen radicals, hydroxyl radicals and oxygen radicals. Regarding metals, it is a problem that heavy metals are contained in sewage sludge in particular, but this problem is caused by the fact that heavy metals are incorporated in fat-soluble proteins and cannot be removed properly by electrolysis or the like. is there. In the present invention, the generated active species can be reacted with a fat-soluble protein, decomposed, and wastewater containing heavy metals can be appropriately treated.

  FIG. 11 is a configuration diagram of a steam cleaner equipped with the active species generator according to the present invention, and includes a nozzle 40 at the tip of the opening of the active species generator of Example 1 and the bottom of the container 4 having water 5. The moving means 41 is provided. The nozzle 40 releases active species such as oxygen radicals and hydroxyl radicals generated by the discharge unit 3 and having a sterilizing action, and removes oil, mold and the like adhering to the floor and walls. The nozzle 40 may include a brush or the like for wiping off dirt. The moving means 41 is for moving the entire steam cleaner, and is a caster, for example. One or more moving means 41 may be provided depending on the size and weight of the steam cleaner or the container.

  The steam cleaner of the present invention is different from the conventional steam cleaner in that it has a strong sterilizing action. A conventional steam cleaner is a cleaning tool that removes dirt by the power of high-temperature and high-pressure steam, and also has a sterilizing action by heat. In contrast, the steam cleaner of the present invention releases active species such as oxygen radicals and hydroxyl radicals having a sterilizing action in addition to high-temperature and high-pressure steam. Therefore, Clostridium botulinum that could not be sterilized by conventional steam cleaners. It is possible to sterilize various types of spore such as spore and tetanus spore.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and the scope of the present invention is indicated by the scope of claims, and the meaning and scope equivalent to the scope of claims. All changes within are intended to be included.

  For example, in the embodiment of the present invention, a wire electrode is used as the discharge electrode 8, but it may be needle-shaped, spherical, or saw-tooth shaped.

  The voltage applied to the discharge electrode 8 is set according to the shape of the electrodes, the distance between the electrodes, the amount of active species to be generated, and the like. The voltage waveform is most preferably direct current, but direct current, pulse, or alternating current may be used and is not specified.

  Further, according to the present invention, not only active species but also ions can be generated, so that it can be used as an ion generator. For example, if a negative voltage is applied to the discharge electrode 8 of Example 1 to generate negative ions, a relaxing effect can be produced. In addition, if negative and positive ions are generated by applying a negative voltage to the discharge electrode 8 of Example 2 and a positive voltage to the second electrode 13, decomposition of mold and viruses floating in the air, The effect of removing odor can be produced.

  Moreover, the active species generator according to the present invention can be mounted on an air purifier. Air purifiers here are air conditioners, dehumidifiers, humidifiers, air purifiers, fan heaters, etc., mainly in the interior of a house, a room in a building, a hospital room, a car cabin. It is a device that is used to adjust the air in an airplane cabin, a ship cabin, a room that requires a sterile environment, and the like.

  Moreover, the active species generator according to the present invention can be mounted on a sewage purification apparatus. In addition, the sewage purification apparatus here can be used not only for domestic wastewater but also for treatment of factory wastewater containing resist.

  The active species generator according to the present invention can be mounted on a steam cleaner. In addition, the steam cleaner here can mainly wash the surroundings of water such as kitchens, baths, and washrooms, and the floors and walls of hospital rooms and operating rooms. In particular, it is possible to sterilize spores of botulinum bacteria and spores of tetanus bacteria that could not be sterilized even with 100 ° C water vapor spouted from a conventional steam cleaner. It also leads to prevention.

DESCRIPTION OF SYMBOLS 1 Evaporation part 2 Water vapor | steam passage part 3 Discharge part 4 Container 5 Water 6 1st heating means 8 Discharge electrode 9 Counter electrode 10 Voltage application apparatus 11 Opening part 12 2nd heating means 13 Discharge electrode 14 Counter electrode 15 Electron generator 16籠 Electrode 17 Voltage application device 18 Insulator 20 Sewage 21 Active species passage 22 First valve 23 Second valve 30 Indigo carmine aqueous solution 40 Nozzle 41 Moving means 81 Air generator 82 Air passage 83 Opening 84 Processed object 85 Heater 86 High-pressure discharge electrode 91 Tube 92 Water vapor generation part 93 Discharge part

Claims (13)

An active species generator for generating active species,
The active species generator is
Water vapor generating means for generating water vapor;
Heating means for heating the generated water vapor;
A discharge means for generating corona discharge between the discharge electrode and the counter electrode,
The active species generator is characterized in that the water vapor pressure inside the active species generator is higher than the atmospheric pressure outside the active species generator. An active species generator comprising a first active species generator that applies a positive voltage to a discharge electrode and a second active species generator that applies a negative voltage to a discharge electrode,
The first and second active species generators generate water vapor generating means for generating water vapor;
Heating means for heating the generated water vapor;
A discharge means for generating corona discharge between the discharge electrode and the counter electrode,
The active species generator according to claim 1, wherein the first and second active species generators have a water vapor pressure higher than an atmospheric pressure outside the first and second active species generators.   The active species generator according to claim 1 or 2, wherein active species are released to the outside by the pressure generated by the generation of water vapor.   The active species generator according to claim 1, wherein the active species generator includes water inside and changes the water into the water vapor.   2. The active species generator according to claim 1, wherein an electron generator is disposed in the vicinity of the opening of the active species generator.   2. The active species generator according to claim 1, further comprising an electrode to which a voltage having the same polarity as a voltage applied to the discharge electrode is applied between the discharge electrode and the counter electrode.   The active species generator according to claim 1, wherein a direct current voltage is applied to the discharge electrode.   The active species generator according to claim 1 or 2, wherein the discharge means is disposed in the vicinity of the generation of the water vapor. When the applied voltage to the discharge electrode is V1, and the applied voltage to the counter electrode is V2,
V1 <V2 ≦ 0
The active species generator according to claim 1, wherein:   The active species generator according to claim 2, wherein the first active species generator and the second active species generator are provided with water inside and change the water into the water vapor.   An air cleaning device comprising the active species generator according to claim 1.   A sewage purification apparatus comprising the active species generator according to claim 1.   A steam cleaner comprising the active species generator according to claim 1.