JP2011254970A - Air cleaning method and apparatus - Google Patents

Abstract

An object of the present invention is to provide an air purification method and an air purification device for purifying indoor air, which is a living space, by deactivating a causative agent of allergy derived from mites.
[Means for Solving the Problems] An air purification method for inactivating mite allergens contained in air by contacting with a photocatalyst based on titanium oxide while irradiating ultraviolet rays in a state where mist is contained in air. , A housing having an air inlet and an outlet, air introducing means for introducing air containing mite allergen from the inlet into the housing, mist generating means, and introducing mist into the housing An air purification apparatus comprising: a mist introducing means for performing irradiation; an ultraviolet irradiation means for irradiating the air introduced into the housing with ultraviolet light; and a titanium-based photocatalyst having a surface exposed in the housing. It is.
[Selection] Figure 1

Description

  The present invention relates to a method and an apparatus for purifying air by deactivating allergen-causing substances caused by mites in the air.

  Recently, changes in the living environment such as high insulation and high airtightness of houses have made it possible for mites to live indoors all year round. In addition, mite foods are dandruff, dirt, mold, etc. If left untreated, it is said that mites will explode in everyday life.

  Allergic causative substances are contained in mite excreta and carcasses, and it is said that there are more patients with perennial allergic rhinitis caused by ticks than hay fever patients.

  Therefore, it is desired to develop an air purification technology that deactivates the causative agent of mite-derived allergy in the air.

  As a purification technique for allergen-causing substances, a method of spraying a liquid into the air and releasing air ions into the air (for example, see Patent Document 1), a method of filtering dust in the air with a filter (for example, a patent) Document 2), a method of putting clothes and the like holding mites in a storage container, and generating ozone in the container with an ozone generator (see, for example, Patent Document 3), a method of treating air with a processing gas such as formaldehyde (See, for example, Patent Document 4).

  However, these methods are inadequate as a method for inactivating the causative substance of allergy caused by mites, or are incomplete as a method for purifying indoor air as a living space.

JP 2006-340843 A JP 2006-204571 A Japanese Patent Laid-Open No. 5-58826 JP-A-2005-74023

  An object of the present invention is to provide an air purification method and an air purification device for purifying indoor air, which is a living space, by inactivating a causative substance of allergy derived from ticks.

  The gist of the present invention is an air purification method in which mite allergen contained in air is deactivated by contacting with a photocatalyst based on titanium oxide while irradiating ultraviolet rays in a state where water mist is contained in the air. There is to be.

  In the air purification method, the mite allergen-containing air is continuously passed through the treatment zone, and the photocatalyst is contacted while irradiating the ultraviolet light with the air containing the water mist in the treatment zone. Can be.

  The air containing mite allergen may be obtained by scraping mite allergen contained in the napped floor surface into the air with a brush.

Further, the gist of the present invention is a housing having an air inlet and an outlet,
Air introduction means for introducing air containing mite allergen into the housing from the inlet;
Water mist generating means;
Mist introduction means for introducing water mist into the housing;
Ultraviolet irradiation means for irradiating the air introduced into the housing with ultraviolet rays;
It is an air purifying apparatus comprising a titanium-based photocatalyst whose surface is exposed in the housing.

  The air purifier may be capable of pulling and / or pushing the floor.

The air purification device may further include scraping means for scraping the floor surface of the raised structure with a brush and scraping mite allergen contained in the floor surface of the raised structure into the air,
Air containing mite allergen scraped by the scraping means may be introduced into the housing from the inlet.

  ADVANTAGE OF THE INVENTION According to this invention, the air purification method and air purification apparatus which purify the indoor air which is a living space by deactivating the causative substance of the allergy derived from a tick are provided.

Side surface explanatory drawing which shows an example of the aspect of the air purification apparatus of this invention. The graph which shows the time-dependent change of the antigenic residual rate of mite allergen. Side surface explanatory drawing which shows another example of the aspect of the air purification apparatus of this invention.

  In the air purification method of the present invention, the air containing mite allergen is converted into a photocatalyst based on titanium oxide while irradiating ultraviolet rays in a state of containing water mist (hereinafter, mist is water mist). Make contact. An example of an embodiment of the air purification device of the present invention used in this air purification method is shown in FIG. In the present specification, the same reference numerals used throughout the drawings indicate members or objects having the same or similar functions.

  In FIG. 1, an air purification device 2 of the present invention includes a housing 4, an air introduction means 9 for introducing air 8 containing mite allergen (allergen causing substance) into the housing 4 from an introduction port 6, and mist generation. Means 12; mist introduction means 16 for introducing mist 14 generated by mist generation means 12 into housing 4; ultraviolet irradiation means 20 for irradiating air 18 introduced into housing 4 with ultraviolet rays; 4 and a photocatalyst 22 based on titanium, the surface of which is exposed.

  The housing 4 includes an air inlet 6 and an outlet 26, and air introduced from the inlet 6 into the housing 4 by the air introduction means passes through the housing 4 and is discharged from the outlet 26. As an aspect of the air introduction means 9, there is exemplified a configuration in which the suction port 32 of the suction fan 30 is connected to the discharge port 26 to suck out the air in the housing 4 and release it outside the housing 4. In this case, air outside the housing 4 flows into the housing 4 from the introduction port 6 by sucking air in the housing 4 from the discharge port 26.

  With the configuration of such an apparatus, the mist 14 is mixed in the air 18 introduced into the housing 4, and at the same time, ultraviolet rays are irradiated by the ultraviolet irradiation means 20. At the same time, the air 18 mixed with the mist 14 contacts the photocatalyst 22 based on titanium.

  Examples of the ultraviolet irradiation means 20 include a low pressure mercury lamp. The wavelength of the ultraviolet light is preferably 185 nm or 254 nm.

  The mist generating means 12 preferably includes an ultrasonic transducer 13 and a storage tank 15. The ultrasonic vibrator 13 is operated by being submerged in the water 17 stored in the storage tank 15 to generate mist 14 on the water surface. The mist introducing means 16 includes a fan 21 installed on the upper part of the storage tank 15 and a duct 25. The duct 25 connects the inside of the storage tank 15 and the inside of the housing 4 via the upper side wall of the storage tank 15. The mist in the storage tank 15 is introduced into the housing 4 by the wind pressure of the fan 21 and mixed into the air 18 introduced into the housing 4. It is preferable that the density | concentration (weight of the liquid which comprises the mist with respect to the volume of air) of the mist in the housing 4 is 0.01-1 g / L.

The photocatalyst used in the present invention is a substance that exhibits a catalytic action when irradiated with light. Among such photocatalysts, titanium oxide (TiO ₂ ) is known as a typical photocatalyst. Further, as a photocatalyst, apatite-coated titanium oxide, zinc oxide (ZnO), tungsten oxide (WO ₃ ), strontium titanate (SrTiO ₃ ), cadmium sulfide (CdS), barium titanate (BaTiO ₃ ), potassium niobate (K ₂ NbO ₃ ), iron oxide (Fe ₂ O ₃ ), tantalum oxide (Ta ₂ O ₅ ), tin oxide (SnO ₂ ), bismuth oxide (Bi ₂ O ₃ ), nickel oxide (NiO), copper oxide ( Examples thereof include Cu ₂ O), silicon oxide (SiO ₂ ), molybdenum sulfide (MoS ₂ ), indium lead (InPb), ruthenium oxide (RuO ₂ ), and cerium oxide (CeO ₂ ). These may use only 1 type and may use 2 or more types together.

  The photocatalyst 22 may be in the form of particles and fixed to the surface of the metal substrate with a resin-based or ceramic-based adhesive. Alternatively, it may be coated on the surface of a glass substrate or other ceramic substrate. Specific examples include trade name Cleartect manufactured by Nippon Sheet Glass Co., Ltd.

Examples of the ultraviolet irradiation means 20 include a low-pressure mercury lamp 35 and the like. The linear intensity of the ultraviolet rays is preferably about 1 to 100 mW / cm ² at a position 10 cm away from the light source. The low-pressure mercury lamp 35 is installed in a lamp chamber 37 partitioned by glass.
Reference numeral 41 denotes a power supply unit for the low-pressure mercury lamp 35 and the ultrasonic vibrator 13. The power supply unit 41 is connected to an external power supply with a cord (not shown).

  In general, mite allergens are known to be deactivated to some extent by ultraviolet irradiation. This seems to be because ozone generated by ultraviolet irradiation inactivates mite allergens. However, since the lifetime of ozone generated in this way is extremely short, this deactivation effect was limited. In the present invention, by mixing mist in the air containing mite allergen, the mite allergen is adsorbed by the mist particles, and the ozone containing water is absorbed by irradiating the air containing water particles adsorbing the mite allergen with ultraviolet rays. The effect of deactivating the mite allergen by being adsorbed or absorbed by the particles is maintained, and the deactivation effect is increased.

  Further, in the present invention, mite allergen or water particles adsorbed with mite allergen are brought into contact with the photocatalyst 22 based on titanium, whereby deactivation due to ultraviolet irradiation is promoted. This is presumably because the chemical change of mite allergen is promoted by ultraviolet irradiation, photocatalyst 22 and water. The photocatalyst 22 may be provided not only on the inner bottom surface of the housing 4 but also on the inner side surface and the inner upper surface of the housing 4.

  Mist water evaporates after being released from the housing 4 and ozone disappears in a relatively short time. Therefore, in the present invention, chemical substances do not remain permanently in the air by the treatment.

  The effect of the present invention is supported by the following experimental examples.

Experimental Example Sample: As a tick antigen, purified mite antigen Der f1 (Asahi Breweries) derived from feces of dermatophagoides farinae was used.
Deactivation treatment: The sample was made into an aqueous solution with a concentration of 50 μg / mL, 1 cc was placed in a 50 mmφ petri dish, and irradiation (irradiation distance: 200 mm) with a germicidal lamp (wavelength 254 nm) (Matsushita Electric) and a fluorescent lamp (Hitachi) was attempted. . Photocatalyst: Titanium dioxide powder P-25 (Nippon Aerosil) was used. The mite antigen was irradiated with light generated from these light sources for a predetermined time, and the residual activity of the mite antigen was measured.
Quantitative measurement of allergen: Tick antigenicity was evaluated by enzyme immunoassay using Kona leopard mite ELISA kit (Der f1) (Nichinichi Pharmaceutical). Quantification was performed at an absorption wavelength of 415 nm using a multimode plate reader (Beckman Coulter DTX800). The ratio of the activity value at the time of measurement to the activity value before the deactivation treatment was defined as the antigenic residual ratio.
Experiment level: Case 1: Fluorescent light irradiation
Case 2; germicidal lamp irradiation
Case 3: Fluorescent lamp irradiation + Titanium dioxide powder (irradiation with 1% by weight of titanium dioxide powder added to aqueous solution)
Case 4: Sterilization lamp irradiation + titanium dioxide powder (irradiation with 1% by weight of titanium dioxide powder added to aqueous solution)

  According to the experimental results shown in FIG. 2, the mite antigen is hardly inactivated by 120 minutes of fluorescent lamp irradiation. In the germicidal lamp, the residual rate of mite antigen was about 20% after 60 minutes of irradiation, and the residual rate of mite antigen was 10% or less after 120 minutes of irradiation. In the fluorescent lamp irradiation in the presence of titanium dioxide powder, the residual rate of mite antigen is already about 35% before irradiation, the residual rate of mite antigen is about 10% after 30 minutes irradiation, and about 5 after 60 minutes irradiation. %. When irradiated with a fluorescent lamp in the presence of titanium dioxide powder, the residual rate of mite antigen was already about 35% before irradiation, and the residual rate of mite antigen was about 3% after 30 minutes of irradiation. Thus, the combined use of germicidal lamps (ultraviolet rays) and photocatalysts (titanium dioxide powder) was most effective.

  In another aspect of the present invention, an air purification device 2a of the present invention shown in FIG. 3 is used. The air purification device 2a includes a housing 4a, air introduction means (not shown) that introduces air 8 containing mite allergen (cause of allergy) into the housing 4a, an mist generating means 12, A mist introducing means 16 for introducing the mist 14 generated by the mist generating means 12 into the body 4a, an ultraviolet irradiation means 20 for irradiating the air 18 introduced into the housing 4a with ultraviolet light, and a surface in the housing 4a. It is comprised including the exposed photocatalyst 22 based on titanium.

  A plurality of through holes 34 are formed in the bottom 33 of the housing 4a, and constitute the inlet 6a. The discharge port 26 is connected to an air suction / discharger (not shown) having a suction fan. The air suction / discharger may be, for example, a household vacuum cleaner, and air is introduced into and discharged from the housing 4a by connecting the suction port of the household vacuum cleaner to the discharge port 26.

  The housing 4a is mounted on a frame base 40 having wheels 44 so that the floor surface 50 can be pulled and / or pushed by human power. The frame base 40 and the bottom of the housing 4a may be integrated.

  Further, a rotating brush 55 is attached to the side facing the floor surface 50 on the opposite side of the frame base housing 4a. The rotating brush 55 is rotationally driven by a driving means (not shown) mounted on the frame base 40, and scratches the floor surface 50 of a napped structure such as a carpet. The mite allergen contained in the napped floor 50 is scraped out by the rotating brush 55 and released into the air. Air containing mite allergen released into the air is sucked and introduced into the housing 4a from the inlet 6a.

  Air introduced from the introduction port 6a into the housing 4a by the air introduction means passes through the housing 4a and is discharged from the discharge port 26. Mist 14 is mixed in the air 18 introduced into the housing 4a, and at the same time, ultraviolet rays are irradiated by the ultraviolet irradiation means 20. At the same time, the air 18 mixed with the mist 14 contacts the photocatalyst 22 based on titanium.

  Reference numeral 41 a is a power supply unit for driving the low-pressure mercury lamp 35, the ultrasonic vibrator 13, and the rotating brush 55. The power supply unit 41a is connected to an external power supply with a cord (not shown).

  In this way, the air purifier 2a of the present invention can efficiently remove and deactivate the mite allergen contained in the floor surface 50 of the napped structure.

  In addition, the present invention can be carried out in a mode in which various improvements, modifications, and changes are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention. For example, in the air purification devices 2 and 2a, a filter for trapping dust may be provided at the inlets 6 and 6a or the outlet 26.

  The present invention is applicable not only to mite allergens but also to purification of air containing various allergens contained in the air.

2, 2a: Air purification device 4, 4a: Housing 6, 6a: Introduction port 8, 18: Air 9: Air introduction means 12: Mist generation means 13: Ultrasonic vibrator 14: Mist 15: Storage tank 16: Mist Introduction means 17: Water 20: UV irradiation means 22: Photocatalyst 26: Discharge port 30: Suction fan 21: Fan 25: Duct 34: Through hole 35: Low pressure mercury lamp 37: Lamp chamber 40: Frame base 41, 41a: Power supply 44: Wheel 50: Floor 55: Rotating brush

Claims (6)

An air purification method in which mite allergen contained in air is deactivated by contacting with a photocatalyst based on titanium oxide while irradiating ultraviolet rays in a state where water mist is contained in the air. The air containing mite allergen is allowed to contact the photocatalyst while irradiating the ultraviolet ray in a state where the air contains the water mist continuously in the treatment area through the air containing the mite allergen. Air purification method. The air purification method according to claim 2, wherein the air containing the mite allergen is obtained by scraping out mite allergen contained in the napped floor surface into the air with a brush. A housing having an air inlet and an outlet;
Air introduction means for introducing air containing mite allergen into the housing from the inlet;
Water mist generating means;
Mist introduction means for introducing water mist into the housing;
Ultraviolet irradiation means for irradiating the air introduced into the housing with ultraviolet rays;
An air purification apparatus comprising a titanium-based photocatalyst having a surface exposed in the housing. The air purifier according to claim 4, wherein the air purifier can be pulled and / or pushed. Furthermore, scraping means to scrape the mite allergen contained in the floor surface of the napped structure in the air by scraping the floor surface of the napped structure with a brush,
The air purifier according to claim 5, wherein air containing mite allergen scraped by the scraping means is introduced into the housing from the inlet.

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