JP3518784B2 - Method and apparatus for removing harmful components in gas - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to removal of harmful components in a gas, and more particularly to a removal method and device for atomizing and collecting harmful components in a gas by ultraviolet irradiation.

[0002]

2. Description of the Related Art Conventionally, harmful substances in gases have been removed by cleaning air such as air cleaning at home, office, hospital and hotel, sewage drainage, purification of exhaust gas in various industries such as waste treatment plants, and atmosphere in the factory. Purification of exhaust gas from underground parking lots and tunnel ventilation, or clean rooms in various industries such as semiconductor industry, pharmaceutical industry, food industry, agriculture and forestry industry, pharmaceuticals, precision machinery industry, closed spaces in aseptic rooms, such as safety cabinets, clean boxes, valuables It is used to clean goods storage, wafer storage, sealed transfer space for valuables, and clean sealed space (in the presence of various gases). For foul odor pollution by harmful gas in offices, acidic gas (eg, aldehyde, hydrogen sulfide, acetic acid, fatty acid, mercaptans), alkaline gas (eg, ammonia, trimethylamine), neutral gas (eg, sulfides) There are complex odors that give off a bad odor when mixed, and specifically, there are cigarette odor, toilet odor, rotten odor, and cooking odor.

Taking the tobacco odor as an example, the tobacco odor is
Remarkably various components such as harmful gas and particulate matter (1,000
It is a typical complex odor pollution consisting of 0 or more kinds), and its main components, aldehyde and nicotine, are carcinogenic or toxic, so tar content, fine particles (smoke) At the same time, there is a strong demand for its collection and removal. For the removal of such tobacco odor, methods using various collecting / removing materials such as activated carbon and plant essential oils and fragrances aiming at the masking effect have been proposed. It does not meet the requirements for odor removal. Therefore, an effective deodorizing method or device is desired. Next, the pollution by harmful gas in the clean room of the semiconductor industry will be described. The air cleaning methods of the conventional clean room or the apparatus therefor are roughly classified into (1) a mechanical filtration method (for example, HEPA filter) (2) a charging method by a high voltage that electrostatically repairs fine particles and a filtration method by a conductive filter (For example, HESA filter), but these methods are all intended to remove fine particles (particulate matter), and hydrocarbon (HC), NO
However, it has a drawback that it is not effective in removing gaseous pollutants (toxic gas components) such as x and NH ₃ .

H. 2 which is a gaseous pollutant (hazardous gas component). Combustion decomposition method, catalytic decomposition method, O
_{3 The} decomposition method is known. However, these methods have a very low H.V. concentration in the air introduced into the clean room. C
It has no effect on removal. In a clean room, H.O.V. having a low concentration in the air, which is caused by automobile exhaust gas, clean room components, synthetic resin (commercial products), etc. C also poses a problem as a pollutant. In particular, H. Substances having a large molecular weight of C ₁₀ or more in C have a great adverse effect on wafers, semiconductor products, semi-finished products, and raw materials, and must be removed ("Air Cleaning", Vol. 33, No. 1, p16-21, 1995). ).
Further, various solvents (for example, alcohols, ketones, etc.) generated in the work in the clean room also pose a problem as contaminants.

In addition, H. As harmful components other than C, N
There are Ox, NH _{3 and the} like, and as a method for removing them, a method based on a neutralization reaction or an oxidation reaction using an appropriate alkaline substance or acidic substance is known. However, these methods are also less effective when the component concentration is an extremely low concentration such as contained in the air introduced into the clean room. In addition, depending on the field of use, it is preferable to add a function of removing fine particles to the function of removing harmful gas, but there is no effective gas cleaning method or device having both of these functions, and the demand for this is also dependent on the field. high. On the other hand, the present inventors first irradiate the gas with ultraviolet rays to atomize harmful components,
A method of collecting the charged fine particles after charging the fine particles with photoelectrons has been proposed (JP-A-4-243517).
And Japanese Patent Laid-Open No. 5-96125). Although these methods were effective depending on the application field, there was room for improvement in practical use.

Regarding the above-mentioned improvement points, FIG.
This will be described with reference to FIG. 2) of Japanese Patent Publication No. 43517. Figure 4
This is a device having a configuration in which the atomizing section (A) for harmful components (harmful gas) and the charging section (B) for charging the particles by generation of photoelectrons are performed in the same part. As described above, in the case of the structure in which the atomizing portion (A) and the charging portion (B) are simultaneously performed in one portion, there are the following problems. That is, the wavelength of the ultraviolet ray from the ultraviolet lamp 1 for the fine particles of the harmful component is at least the ultraviolet ray which causes ozone generation, for example, 185n.
m (vacuum ultraviolet range). The presence of such short-wavelength ultraviolet rays and the generated ozone adversely affects the stability of the photoelectron emission material 3 for generating the photoelectrons 2, and causes a problem of performance deterioration in long-term use. .

[0007]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and removes harmful components in a gas that can effectively generate photoelectrons for a long time without performance deterioration of the photoelectron emitting material. It is an object to provide a method and its apparatus.

[0008]

In order to solve the above problems, in the present invention, harmful components present in a gas are made into fine particles by irradiation of ultraviolet rays, and the fine particles are charged by photoelectrons generated by irradiation of ultraviolet rays and collected. In the method for removing harmful components in a gas to be collected, an ultraviolet ray source having a wavelength of 200 nm or less and a wavelength of 250 nm or more is simultaneously used as the ultraviolet rays, and the harmful components in the gas are atomized under irradiation of the ultraviolet rays. Ozone is removed from the gas, and photoelectrons generated by irradiating the photoelectron-emitting substance with ultraviolet rays having a short wavelength of 200 nm or less cut off from the ultraviolet rays are charged to charge the fine particles in the gas from which the ozone has been removed, thereby charging the charged fine particles. It was decided to collect.

Further, according to the present invention, the harmful component in the gas having an ultraviolet ray source, a microparticulation part for micronizing harmful components, a charging part for charging the microparticles with photoelectrons and a trapping part for collecting the charged microparticles In the removing device, an ultraviolet ray source having a wavelength of 200 nm or less and a wavelength of 250 nm or more is simultaneously provided in the atomizing section, and an ozone decomposing section in which an ozone decomposing material is arranged is connected to the atomizing section, and the ultraviolet ray source is provided. ultraviolet rays from are the charged portion is irradiated through the light emission material coated with photoelectron emitting substance to short wavelength UV cut filter for cutting the 200nm following ultraviolet rays disposed between the charge section of micronized portion and the fine particles It is provided.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Next, each structure of the present invention will be described in detail. In the present invention, the ultraviolet ray source for irradiating with ultraviolet rays is an ultraviolet ray that atomizes harmful components in the gas to be treated by irradiation, that is, an ultraviolet ray having a wavelength of 200 nm or less, for example, 184 nm (vacuum ultraviolet region), 250
Any ultraviolet ray having a wavelength of nm or more, for example, an ultraviolet ray having a wavelength of 254 nm may be used. As such a light source, there is a low pressure mercury lamp. 20 in the present invention
Ultraviolet rays having a wavelength of 0 nm or less atomize harmful components into fine particles, while ultraviolet rays having a wavelength of 200 nm or less generate ozone by irradiation into the air. For example, with one 0.7 W UV lamp (GLK-8 manufactured by Sankyo Denki), the air flow rate is 1.0
Approximately 1 when operated at ~ 4.5 l / min
5-45 ppm ozone was generated.

Next, the ozone decomposing section is located behind the ultraviolet ray irradiating section (atomizing section for harmful components) which is irradiated with ultraviolet rays having a wavelength of 200 nm or less, which causes ozone generation. Install an ozone decomposing material in front. This ozone decomposing unit is an ultraviolet irradiation unit (particulate atomizing unit).
It is provided in order to prevent the ozone generated in step 2 from entering the charged part of the rear particles. Any ozone decomposing material may be used as long as it can efficiently decompose ozone generated by ultraviolet irradiation. Usually, there are activated carbon (granular and fibrous), metal catalysts, and complex oxide catalysts. As an example of the complex oxide type catalyst, a manganese dioxide type catalyst such as MnO ₂ / T is used.
iO ₂ -C, there is MnO ₂ / ZrO-C. The manganese dioxide-based catalyst is obtained by sintering the powder into pellets,
Alternatively, it may be supported on a pellet-shaped, honeycomb-shaped molded product, a honeycomb-shaped base material or a fibrous base material. Further, manganese dioxide to which an appropriate metal or metal compound is added can be used for suppressing deterioration, preventing performance deterioration in a low temperature range, and improving activity.

Next, the photoelectron emitting material will be described. The photoelectron emitting material of the present invention comprises a short-wavelength ultraviolet cut filter coated with a photoelectron emitting substance. The photoelectron-emitting substance used in the present invention does not receive irradiation with short wavelength ultraviolet rays of 200 nm or less and emits photoelectrons by irradiation of ultraviolet rays of 250 nm or more. Therefore, a photoelectron emitting substance is coated on the short wavelength ultraviolet cut filter.
The short-wavelength ultraviolet cut filter may be any one as long as it can cut ultraviolet rays having a wavelength of 200 nm or less and can be coated with a photoelectron emitting substance. Usually, short-wavelength ultraviolet-absorbing glass and short-wavelength ultraviolet-absorbing Teflon material are used. Among them, short-wavelength ultraviolet-absorbing glass is preferable from the viewpoint of long-term stability.

The photoelectron emitting substance may be any substance as long as it emits photoelectrons to its surface and its vicinity upon irradiation with ultraviolet rays having a wavelength of 250 nm or more, and the one having a smaller photoelectric work function is preferable. B from the viewpoint of effect and economy
a, Sr, Ca, Y, Gd, La, Ce, Nd, Th,
Pr, Be, Zr, Fe, Ni, Zn, Cu, Ag, P
t, Cd, Pb, Al, C, Mg, Au, In, Bi,
Nb, Si, Ti, Ta, U, B, Eu, Sn, P, W
Or any of these compounds or alloys or mixtures thereof, and these are used alone or in combination of two or more. As the composite material, a physical composite material such as amalgam can also be used. For example, compounds include oxides, borides, and carbides, and oxides include BaO, SrO, and Ca.
O, Y ₂ O ₅ , Gd ₂ O ₃ , Nd ₂ O ₃ , ThO ₂ , Z
rO ₂ , Fe ₂ O ₃ , ZnO, CuO, Ag ₂ O, La
₂ O ₃ , PtO, PbO, Al ₂ O ₃ , MgO, In _{2
O 3, BiO, NbO, YB} 6 is to include BeO, also _{borides, GdB 6, LaB 5, NdB} 6, CeB
₆ , EuB ₆ , PrB ₆ , ZrB _{2 and the} like, and as carbides, UC, ZrC, TaC, TiC, Nb.
C, WC, etc.

As the alloy, brass, bronze, phosphor bronze, copper, and an alloy of Ag and Mg (Mg is 2 to 20 wt.
%), An alloy of Cu and Be (Be is 1 to 10 wt%) and an alloy of Ba and Al can be used. The alloy of Ag and Mg, the alloy of Cu and Be and the alloy of Ba and Al can be used. Alloys are preferred. The oxide can also be obtained by heating only the metal surface in air, or by oxidizing with a chemical. As another method, it is also possible to heat before use to form an oxide layer on the surface to obtain a stable oxide layer for a long period of time. As an example of this, an alloy of Mg and Ag can form an oxide film on its surface in water vapor at a temperature of 300 to 400 ° C., and this oxide thin film is stable for a long period of time. Further, as already proposed by the present inventors, a material having a multilayer structure of these materials can be preferably used (Japanese Patent Application No. 1-155857).

The photoelectron emitting material can be prepared by coating the short-wavelength ultraviolet cut filter with the photoelectron emitting substance by an appropriate method such as a vapor deposition method or a sputtering method. In coating the photoelectron emitting substance, first, a conductive substance (for example, ITO) may be coated and then applied (Japanese Patent Laid-Open No. 5-68875). The emission of photoelectrons from the photoelectron emitting material can be effectively performed by appropriately using a reflective surface, a curved reflective surface, or the like, as already proposed by the present inventor (Japanese Patent Publication No. 6-34941).
Issue). The shapes of the photoelectron emitting material and the reflecting surface differ depending on the shape and structure of the device or the desired efficiency, and can be appropriately determined. When the photoelectron emitting material is irradiated with ultraviolet rays under an electric field, the emission of photoelectrons becomes effective. The present inventors have already proposed charging in an electric field (Japanese Patent Publication No. 3-5859 and Japanese Patent Laid-Open No. 2-303557).
No.

As the collecting material (dust collecting material) for the charged fine particles, any material can be used as long as it can collect the charged fine particles. Dust collecting plate, dust collecting electrode in an ordinary charging device, various electrode materials, and electrostatic filter method are generally used, but the collecting part itself such as steel wool electrode or tungsten wool electrode constitutes a wool-like structure. Things are also valid. Electret materials can also be preferably used. Further, the method of collecting by using the ion exchange filter (or fiber), which the present inventor has already proposed, is also effective (Japanese Patent Publication No. 6-8).
7997). For collection, these collection methods can be used alone, or two or more kinds of these methods can be combined and appropriately used. As the electrode material for the electric field, those used in ordinary charging devices can be preferably used. That is, a known one can be used. The electrode material for an electric field can be used also as or integrated with the charged particle collecting material (dust collecting material). For example, among the above-mentioned charged particulate matter collecting materials, various electrode materials such as a dust collecting plate, a dust collecting electrode, or a wool-like electrode material such as a steel wool electrode and a tungsten wool electrode are used as the electric field electrode material and the charged particulate matter collecting material. It is preferable because it can also serve as a collection.

Further, a material other than the electrode material such as an electret material or an ion exchange filter (a material characterized by collecting fine particles) can be integrally used with the above-mentioned appropriate electric field electrode material. As described above, in the present invention, 200
By using the ultraviolet rays from the ultraviolet source having both the ultraviolet rays of less than or equal to 250 nm and the wavelength of 250 nm or more, only the ultraviolet rays of 250 nm or more are irradiated to the photoelectron emitting material, whereby the charged portions of the fine particles are irradiated with the ultraviolet rays. However, ozone is not generated in the gas to be treated. Therefore, the environment near the surface of the photoelectron emitting material is ozoneless, and
Since only long-wavelength ultraviolet light having a wavelength of 0 nm or more (ultraviolet energy is low), the attack on the photoelectron emitting material does not become stronger than necessary. That is, photoelectrons are generated under mild conditions. Therefore, even if the photoelectron emitting material is used for a long time, there is no deterioration or deterioration in performance, and the photoelectron emitting material can be used for a long time.

[0018]

EXAMPLES The present invention will be specifically described below with reference to examples. Example 1 FIG. 1 shows a schematic configuration diagram in which a harmful component removing device is installed in a clean room, and harmful gas and fine particles are collected and removed by the same device. In FIG. 1, class 1000 (> 0.1)
(μm) in the clean room 10
The harmful gas such as x, NH ₃ , SOx, and the fine particles 12 are generated, and the harmful component removing device 13 is installed to collect and remove the harmful gas and the fine particles. The device 13
Is mainly a pretreatment filter 6, a harmful gas atomizing section A, an ozone decomposing section C, a photoelectron particle charging section B,
Is composed from the collection part D of charged particles, the air to be treated 5 _-1 containing toxic components 12 containing hazardous gases and particulates, arrow 5 _-2 apparatus 13 by the fan 7, in the direction of _5-3 A stream of purified air 5 _-4 is obtained. This air is ultra-clean air from which harmful gases and fine particles have been removed,
It is used as a supply gas for the clean tunnel, air knife, stocker, and production line in the clean room 10.

Each component will be described. Preprocessing filter unit 6, the coarse filter is filled, coarse particles in the suction air _5-1 are removed. Here, a filter mainly made of glass fiber having a low air resistance is used. The harmful gas atomization part A is mainly 184 nm and 2
An ultraviolet source (low pressure mercury lamp) 1 that emits 54 nm ultraviolet rays is installed, and harmful gas in the air to be treated is atomized therein. Here, it is a place where harmful gas (gaseous pollutant) is converted into particles that are easy to handle. The gaseous pollutant mainly has a particle size of about several tens nm (example 30 nm) due to UV energy of 184 nm. Converted to sized particles. Here, about 25 ppm of ozone is generated from the air to be treated by the irradiation of ultraviolet rays of 184 nm. The ozone decomposing section C is a place for decomposing and removing ozone generated in the harmful gas atomizing section A, and is a honeycomb-like manganese dioxide-based catalyst (MnO ₂ / TiO ₂₎ which is a complex oxide-based catalyst.
-C) is used. Here, 25 ppm ozone is decomposed and removed to 0.1 ppm or less.

The charge section B of the microparticles by photoelectrons, the fine particulate matter and the air to be treated 5 _-1 from the gaseous pollutants, is where charged by photoelectrons 2. The photoelectron emitting material that emits photoelectrons is the short-wavelength ultraviolet absorbing glass 8,
Au3 is coated as a photoelectron emitting substance.
The charging mechanism of the particulate matter by the photoelectrons 2 generated from the photoelectron emitting material (8 + 3) has already been clarified by the study by the present inventors (aerosol study, No. 8).
Vol. 3, No. 3, pp. 239-248, 1993). The ultraviolet rays irradiating the photoelectron emitting material (8 + 3) are only 254 nm ultraviolet rays because the 184 nm ultraviolet rays are absorbed by the short wavelength ultraviolet absorbing glass 8. 4 is an electrode material for performing photoelectron emission under an electric field. The charged particle collecting portion D is a place upstream of collecting and removing charged particles.

Example 2 In FIG. 2, in the harmful component removing apparatus 13 of Example 1, ITO (transparent conductive material) was used as the base of the photoelectron emitting substance Au.
Is coated. That is, in the configuration of FIG. 2, a short wavelength ultraviolet absorbing glass material 8 is used as a short wavelength ultraviolet cut filter, and Au 3 and ITO are coated on the surface thereof to be used as a photoelectron emitting material (8 + 3). 2, the same symbols as in FIG. 1 have the same meanings. In the present invention, the harmful gas is mainly removed by particle formation by irradiation with ultraviolet rays of 200 nm or less as described above. On the other hand, in the harmful gas atomization unit, even if there is a case where some particles are not formed due to operating conditions, the harmful gas is a photochemical reaction due to ultraviolet rays having a short wavelength of 200 nm or less, and a reaction due to oxygen active species generated from ozone, And, by adsorbing and decomposing on the surface of the complex oxide-based catalyst by passing a gas containing the gaseous harmful gas and the oxygen active species through the complex oxide-based catalyst, the harmful gas in the gas is effectively decomposed and removed, Be cleaned.

Example 3 An example in which the harmful component removing device shown in FIG. 2 is applied to the cleaning of supply air for drying in a liquid crystal factory will be shown. The device is
It is installed in a class 10,000 room, and NH ₃ and NOx are generated in the vicinity due to acid and alkali cleaning. In order to purify (clean) such air in the clean room as air to be supplied to the drying step of the liquid crystal manufacturing process, FIG.
The toxic substance removing device was installed, and the degree of contamination by fine particles and toxic gas was examined by increasing the contact angle to the glass substrate and the toxic gas component concentration and fine particle concentration. The contact angle indicates the degree of contamination of the surface, and is represented by an angle representing the wettability of the surface. When the contact angle is high, it is contaminated, and when the contact angle is low, it is not contaminated.

Clean room; Class 10,000 (> 0.1 μm) Coarse filter; Glass fiber pretreatment filter Ultraviolet source; Low pressure lamp 10 W (wavelength: 184 nm, 254 nm) Ozone decomposition material; Honeycomb-like manganese dioxide catalyst (MnO) ₂ / TiO ₂ -C) Short-wavelength UV cut filter and photoelectron emission material; UV cut filter (filter that cuts UV light of 220 nm or less to 50% or more and UV light of 200 nm or less to 80% or more), ITO 50 nm, Au 100 nm Coating. Electrodes (for field); Cu-Zn on Au plating charged particle collecting material; electrostatic filter to remove toxic substances device size; 30 × 30 × 40cm (3m from the source) NH ₃ and the NOx concentration in the room; NH _3: 10 ppm, NOx: 5 ppm,

The effect was determined by exposing the air at the outlet of the harmful component removing device to (1) a glass substrate and examining the increase of the contact angle on the substrate using a contact angle meter. Also,
(2) The measurement was performed by measuring the concentrations of NH ₃ , NOx, water and fine particles in the air. Measuring device; Contact angle: Water drop type contact angle meter NH ₃ : Indophenol method NOx: Chemiluminescence type analyzer HC (Non-methane hydrocarbon): Gala chromatograph with FID Fine particles: Light scattering type particle counter

Results FIG. 3 shows the contact angle (circle mark) when the air treated by the present invention was exposed to the glass substrate for 800 hours. FIG. 3 also shows, as a comparison, the one in which the air in the clean room was directly exposed (marked with ●). In addition, without using the ultraviolet cut filter, which is used for comparison in FIG.
O and Au coated in the same manner are shown by Δ marks. In Fig. 3 ↓
Indicates a detection limit of 4 degrees or less. Table 1 shows the harmful gas and fine particle concentrations in the air in the clean room and the air at the outlet of the air purifier.

[0026]

[Table 1] Class: Number of fine particles of 0.1 μm or more contained in 1ft ^{3 The} photoelectron emission material after 800 hours in FIG. 3 was taken out and ESC
When the surface was examined by an A analyzer, the photoelectron emitting material according to the present method was the same as the photoelectron emitting material at the start, but ITO and A were formed on the quartz glass as the above comparison.
In the case where u was coated, a part of the underlying ITO was moved upward. From this, it is considered that the composition (structure) of the conventional photoelectron emitting material is changed by the irradiation of ultraviolet rays of short wavelength for a long time.

[0027]

As described above in detail, the following effects can be obtained by adopting the configuration of the present invention. (1) As the ultraviolet ray source, one containing ultraviolet rays having a wavelength of 200 nm or less and ultraviolet rays having a wavelength of 250 nm or more is used.
These ultraviolet rays are used as fine particles of harmful components, and in charging the fine particles by photoelectrons, by using a short-wavelength ultraviolet cut filter with a photoelectron-emitting material coated with a photoelectron-emitting material and irradiating with ultraviolet rays, (a) photoelectron emission is obtained. Since the irradiation of short wavelength ultraviolet rays to the organic substance and the exposure of the generated ozone were eliminated, there was no strong irritation to the photoelectron emitting substance. As a result, the photoelectron emitting material became stable for a long time without deterioration and performance deterioration.

(2) By using a complex oxide catalyst as an ozone decomposing material, even if a part of the harmful component is not made into particles due to operating conditions and the like, the harmful component can be reduced to 2 parts.
A photochemical reaction by ultraviolet rays having a short wavelength of 00 nm or less, a reaction by an oxygen active species generated from ozone, and a complex oxide system by passing a gaseous harmful component and a gas containing the oxygen active species through a complex oxide catalyst Adsorption on the catalyst surface
By the decomposition action, the harmful gas in the gas is effectively decomposed and removed to be cleaned. (3) Due to the above (1) and (2), the practicability of the removal system by atomizing harmful components using short wavelength ultraviolet rays is further improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a clean room in which a harmful component removing device of the present invention is installed.

FIG. 2 is a schematic configuration diagram showing an example of a harmful component removing device of the present invention.

FIG. 3 is a graph showing changes in contact angle with exposure time.

FIG. 4 is a schematic configuration diagram of a conventional harmful component removing device.

[Explanation of symbols]

1: UV source, 2: photoelectron, 3: photoemissive substance,
4: Electrode electrode material, 5: Air flow, 6: Pretreatment filter, 7: Fan, 8: Short wavelength ultraviolet absorbing glass, 10:
Clean room, 11: Hazardous component source, 12: Hazardous component, 13: Harmful component decomposing device, A: Fine particle part, B: Charging part, C: Ozone decomposing part, D: Collection part

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Claims (2)

(57) [Claims] 1. A method of removing harmful components in a gas, wherein harmful components existing in a gas are finely divided by irradiation of ultraviolet rays, and the fine particles are charged by photoelectrons generated by ultraviolet irradiation to collect the fine particles. Using an ultraviolet ray source having the following wavelength and a wavelength of 250 nm or more at the same time, the harmful components in the gas are atomized under the irradiation of the ultraviolet ray, and then ozone is removed from the gas to remove the ozone from the ultraviolet ray.
A gas characterized in that the photoelectrons generated by irradiating a photoelectron-emitting substance with ultraviolet rays having a short wavelength of 200 nm or less are charged to charge fine particles in the ozone-free gas to collect the charged fine particles. How to remove harmful components in the product. 2. A device for removing harmful components in a gas, which comprises an ultraviolet ray source, a microparticulation part for micronizing harmful components, a charging part for charging the microparticles with photoelectrons, and a collection part for collecting the charged microparticles, An ultraviolet ray source having a wavelength of 200 nm or less and a wavelength of 250 nm or more is provided in the atomizing section at the same time, and an ozone decomposing section in which an ozone decomposing material is arranged is connected to the atomizing section, and ultraviolet rays from the ultraviolet ray source are provided. , Provided between the atomization part and the charged part of the particles 20
A device for removing harmful components in a gas, comprising: a short-wavelength ultraviolet cut filter that cuts ultraviolet rays of 0 nm or less; and a charging part that is irradiated through a photoelectron emitting material coated with a photoelectron emitting substance.