JPH09220431A - Device for removing gaseous impurity and air cleaning system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for removing gaseous impurities which has high adsorption performance and is easy to maintain. SOLUTION: This device 100 for removing the gaseous impurities is arranged with plural sets of adsorptive filter medium units 200 capable of removing the gaseous impurities apart spacings from each other in nearly parallel with the main flow direction in a duct. The device is formed with, for example, zigzag air routes in such a manner that the treating air passes at least one adsorptive filter medium unit. The velocity of the air passing the adsorptive filter media is, therefore, made extremely lower than the velocity of main flow air in the duct. The maintenance of the low pressure drop and the high adsorption performance is thus made possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for removing gaseous impurities and an air cleaning system, and more particularly to a device for removing gaseous impurities contained in a clean room atmosphere for manufacturing semiconductor elements (LSI), liquid crystal displays (LCD) and the like. Regarding removal technology.

[0002]

2. Description of the Related Art A so-called HEPA filter (High Efficiency) is one of the manufacturing techniques for improving the yield and reliability in the manufacturing process of LSI and LCD.
PARTICULATE AIR FILTER) and UL
PA filter (Ultra Low Penetrat)
There is a filter for removing fine particles called an ion air filter). These filter technologies have largely contributed to the cleanliness of the manufacturing process. HEPA filters currently guarantee a nominal trapped particle size of 0.0
Although it is 5 μm, practically almost all fine particles of nanometer (thousandth unit of μm) size can be removed. In other words, it can be said that the filter for removing particulates is an already completed technology.

A highly integrated semiconductor device which has recently entered mass production has a fine structure with a wiring size of 0.5 μm and a gate oxide film thickness of 10 nm, as represented by a 16M-DRAM. In the manufacturing process of such a highly integrated semiconductor device, of course, fine particles pose a problem as a pollution source causing product defects. However, the above HEPA filter and U
In the air that has passed through the LPA filter and is being supplied to the clean room, there are almost no particles that can be a pollution source. Therefore, it is considered that the fine particles existing in the clean room are generated by dust generation from the robot, the operator, and the manufacturing apparatus inside the clean room.

Further, in the process of manufacturing a highly integrated semiconductor device having a wiring size of submicron or less, gaseous impurities smaller than fine particles adhere to the clean surface of the product,
Needs for electrical characteristics of elements, selectivity of dry etching and C
It is beginning to affect the adhesiveness of VD multilayer films. Gaseous impurities are atomic / molecular or ionic substances having a size of about angstrom to nm (1 nm = 10 angstrom) that cannot be removed by a HEPA filter.
It is known that the properties of gaseous impurity pollution are more active in terms of physical phenomena such as adsorption / desorption, interface phenomena and chemical reaction phenomena, as compared with particle pollution. The gaseous impurities known to exist in the clean room atmosphere and the causes of their generation are as follows.

(1) Gaseous impurities F ⁻ , Cl ⁻ , SO ₄ ²⁻ , NO ₂ ⁻ , NO ₃ ⁻ , PO ₄ ³⁻ , organic solvent, etc. leaked from manufacturing equipment, exhaust system, etc. (2) Incorporation gaseous impurities NOx derived from ambient air ^-, SOx ^2-, Cl ^-, organic, etc. (3) gaseous impurities NH ₄ derived from such an operator ^{+, Cl -, Na +,} K +, organic matter, etc. (4) cassette Osamu volatile impurities F from such ingredients and wafer receiving member ^-, organics, etc. (5) structures and devices volatile impurities boron compounds from the material of the organic phosphorus compound such as

A so-called chemical filter is known as a device for removing such gaseous impurities. Most of the chemical filters are based on activated carbon, and organic gases can be physically adsorbed and removed as they are. On the other hand, acid-based gas, alkali-based gas, and sulfur-based gas can be removed by chemisorption by a neutralization reaction by adding various impregnating substances to the surface of activated carbon.

The shape of activated carbon which is the base of such a chemical filter includes pellets, fibers and honeycombs. Here, it is known that the ventilation resistance of pellets is overwhelmingly higher than the ventilation resistance of fibrous adsorption filter media or honeycomb. Therefore, what is currently in practical use is a fibrous or honeycomb chemical filter,
These filters have the following drawbacks.

First, the life guarantee of these filters is not clear. That is, the filter life varies greatly, for example, 3 months, 6 months, 1 year, depending on how to estimate the impurity concentration on the inlet side. Further, the adsorption performance of the adsorption filter medium is easily affected by relative humidity, and for example,
When the relative humidity exceeds 40%, water is adsorbed, so that the adsorption performance of impurities to be removed is significantly deteriorated. Further, the conventional chemical filter is often attached to the ceiling surface of the clean room, and when the life of the chemical filter is expected to be short, it is necessary to frequently replace the chemical filter behind the ceiling of the clean room. This replacement work is extremely troublesome.

Secondly, a binder which is a constituent member of the chemical filter other than fibrous or honeycomb activated carbon,
Nonwoven fabrics and gaskets often have poor heat resistance. For example, the honeycomb body is made of activated carbon fiber and a binder, the outer frame and lath wire mesh are made of aluminum, the non-woven fabric is made of polyester, and the gasket is made of silicon. Therefore,
It was difficult to heat and regenerate the activated carbon portion after the chemical filter had been used for its useful life (that is, after the activated carbon lost its adsorption ability). That is, the conventional chemical filter is a disposable filter, and it has been a waste of resources.

Third, since the conventional chemical filter is made of the above-mentioned materials, there is a possibility that organic gas may be generated from the constituent members other than the activated carbon. That is, even if the foreign organic gas can be completely removed by the activated carbon forming the main constituent member of the chemical filter, the impurity gas that is desorbed from other constituent members of the chemical filter (for example, binder, non-woven fabric, gasket), especially There was a risk that organic matter gas would become a new source of pollution.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and an object thereof is to set a short filter life in consideration of a high safety factor, and Even if you do frequent replacement work,
An object of the present invention is to provide a gaseous impurity removing device and an air cleaning system that can easily perform the replacement work.

Another object of the present invention is to provide a gaseous impurity removing device and an air cleaning system which are capable of easily regenerating an adsorbent filter medium of a removing device by heating and are excellent in resource saving. .

Still another object of the present invention is to eliminate the generation of gaseous impurities from the constituent members other than the adsorption filter medium which constitute the removal device, and therefore the constituent members other than the adsorption filter medium do not become a secondary pollution source. To provide a particulate impurity removing device and an air cleaning system.

[0014]

To solve the above problems, according to a first aspect of the present invention, there is provided a device for removing gaseous impurities which is inserted in a duct path. According to a first aspect of the present invention, the apparatus for removing gaseous impurities is arranged such that a plurality of sets of adsorption filter medium units capable of removing gaseous impurities are spaced apart from each other and are substantially parallel to the main flow direction in the duct. The air passage is formed so that the treated air passes through at least one adsorption filter medium unit. With such a configuration, the ventilation wind velocity of the adsorption filter medium can be remarkably reduced as compared with the mainstream wind velocity in the duct, and low pressure loss and high adsorption performance can be maintained.

Each adsorbent filter medium unit of such a device for removing gaseous impurities comprises an adsorbent filter medium and a casing, and a ventilation path is provided at least between adjacent casing surfaces facing each other. It is preferably formed. Further, as described in claim 3, the space formed between the adsorption filter media units is such that, on the upstream side of the duct, closing and opening are repeated at adjacent spaces, and on the downstream side of the duct, the upstream side. It is preferable that the interval closed at is opened and the interval opened at the upstream side is closed. Further, as described in claim 4, it is preferable that each adsorption filter medium unit is detachable via a lid portion of the duct which is configured to be openable and closable.

According to a fifth aspect of the present invention, the casing of the removing device is formed integrally with the duct path, and the filter medium is filled in the casing through an inlet provided vertically above the duct path. It is also possible to discharge the air from the outlet through an outlet provided vertically below the duct path.

When the casing of the removing device is made of an inorganic material such as metal or ceramics, the casing together with the filter medium can be heated to regenerate the used adsorption filter medium. it can.

Further, according to another aspect of the present invention, there is provided an air cleaning system including the above-mentioned gaseous impurity removing device. When a large amount of fine particles as dust is contained in the air to be treated, it causes clogging of the adsorption filter medium. Therefore, as described in claim 7, the particles in the air stream are removed upstream of the gaseous impurity removing device. It is preferable to provide a possible first filtering device, and to provide a second filtering device downstream of the gaseous impurity removing device capable of removing at least particles from the adsorption filter medium of the gaseous impurity removing device. In that case, it is preferable that the second filtering device installed on the downstream side of the removing device is made of a material that does not generate an impurity gas.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the gaseous impurity removing apparatus according to the present invention will be described in detail below with reference to the accompanying drawings.

1 and 2 show a first embodiment of a gaseous impurity removing apparatus according to the present invention.
1 shows a perspective sketch of the gaseous impurity removing apparatus 100 according to the present embodiment, and FIG. 2 shows a schematic plan view of the gaseous impurity removing apparatus 100 of FIG. 1, respectively. As shown, this device 10 for removing gaseous impurities
0 can be installed so as to form a part of the duct 102 that supplies clean air to a clean space such as a clean room.

3 and 4 show a schematic structure of an adsorption filter medium unit 200 applicable to the gaseous impurity removing apparatus 100 according to the present embodiment. As shown in the figure, the adsorption filter medium unit 200 includes a substantially rectangular parallelepiped casing 20.
2 and the adsorptive filter medium 204 filled in the casing. The casing 202 is preferably made of an inorganic material such as metal or ceramics. Since inorganic materials such as metals and ceramics have heat resistance, the saturated adsorption filter medium 204 together with the adsorption filter medium unit 200 is taken out from the removing device 100, and the adsorption filter medium 204 together with the casing 202 is, for example, 100, as will be described later.
It is possible to regenerate the adsorptive filter medium by heating it to ℃ to 120 ℃. Inorganic materials such as metals and ceramics are less likely to generate pollutants and can be decomposed by heat treatment to decompose organic contaminants adhering to the surface, so that the adsorption filter medium unit 200 itself becomes a secondary contaminant source. This can be effectively prevented.

When a pellet-shaped filter medium is used as the adsorption filter medium 204 capable of removing gaseous impurities as in the illustrated example, or when a fibrous filter medium is used, the entire adsorption filter medium 204 is used. Therefore, it is necessary to cover the casing 202 with the suction filter medium 204 so that the adsorption filter medium 204 does not spill from the casing 202. However, in order to ensure air permeability, at least two surfaces should be a ventilation surface 2 such as a mesh or a perforated plate.
02a. On the other hand, the adsorption filter medium 204
As the honeycomb filter medium, when the adsorptive filter medium itself has a breathable rigid structure, the ventilation surface 202a has a casing 2 such as a mesh or a perforated plate.
It is not necessary to cover with 02.

Returning to FIGS. 1 and 2, the arrangement of the gaseous impurity removing apparatus 100 will be described. As shown, a plurality of sets of adsorption filter media units 200 (200a, 2a, 2
00b, 200c ... 200g) are arranged parallel to the air flow direction in the duct indicated by the dotted arrow in the figure, with an appropriate gap between them. The intervals between the adsorption filter medium units 200 may be equal intervals or different intervals. However, it is preferable to arrange each adsorption filter medium unit 200 so that the ventilation surface 202a (FIG. 3) is substantially perpendicular to the air flow direction in the duct. With this configuration, the casing surfaces (the ventilation surface 202) that are adjacent and face each other
A ventilation path is formed between a) and the treated air is at least 1
After passing through one adsorption filter medium unit, gaseous impurities are adsorbed.

Further, according to the present embodiment, as shown in FIG. 2, the adsorption filter medium unit 20 is provided in the removing device 100.
0 (200a-200g), upstream blind plate 206a-20
6d, the downstream blind plates 208a to 208d form a zigzag airflow path. That is, the space formed between the adsorption filter media units 200a to 200g is such that the upstream blind plates 206a to 206d repeatedly close and open at intervals adjacent to each other on the upstream side of the duct air flow, and the downstream side of the duct air flow. At the downstream blind plate 208a
~ 208d opens the gap closed on the upstream side,
The interval opened on the upstream side is configured to be closed, so that a zigzag airflow path passing through at least one adsorption filter medium unit can be formed as shown by a dotted arrow in FIG. With such a zigzag air flow path, it is possible to significantly reduce the aeration air velocity of the adsorption filter medium as compared with the mainstream air velocity in the duct, and achieve low pressure loss and high adsorption performance.

According to the present embodiment, as shown in FIG. 1, an openable / closable lid 104 is attached to the duct portion in which the removing device 100 is installed. With this configuration, the saturated adsorption filter medium 204 can be taken out together with the adsorption filter medium unit 200 by removing the lid 104.
Even when the replacement filter life is set to be short for a high safety factor, the replacement work of the absorption filter medium can be easily performed. In addition, as described above, the casing 2
If 02 is made of an inorganic material such as metal or ceramics, the saturated adsorption filter medium 204 is heated together with the unit,
It becomes possible to regenerate, and it is possible to construct a resource-saving and inexpensive maintenance system.

Further, the apparatus for removing gaseous impurities according to the present invention can be constructed so that its cross section is as shown in FIGS. 5 and 6. As shown in the figure, in the gaseous impurity removing apparatus 300 according to this embodiment, the casing 304 forming a part of the adsorption filter medium unit 302 is integrally formed with the duct 306 in which the removing apparatus 300 is installed. As shown in FIG. 5, this casing 304 forms an adsorption filter medium container 304a that can be filled with a granular or pellet-shaped adsorption filter medium. Also, duct 3
On the upper part of 06, an unused adsorption filter medium container 304 is attached.
An openable / closable inlet 310 to be introduced into a is provided, and an openable / closable outlet 312 for discharging a used adsorption filter medium is provided at a lower portion of the duct 306. Also,
In the removing device 300 according to the present embodiment, the portion 304b of the casing 304 functions as a blind plate that alternately blocks the air path upstream and downstream of the airflow, as in the embodiment shown in FIG. 1 and 2
Similarly to the embodiment shown in FIG.
The casing surface parallel to the air flow in the duct is configured as a ventilation surface made of a mesh or a perforated plate. Therefore, also in the case of this embodiment, a zigzag air path that passes through at least one adsorption filter medium unit is configured as in the case of the previous embodiment, and the same operational effect can be achieved.

However, according to the present embodiment, a new adsorption filter medium unit can be easily introduced by introducing the granular or pelletized adsorption filter medium into the adsorption filter medium container 304a from the upper inlet 310 with the lower outlet 312 closed. Can be configured. Further, the saturated adsorption filter medium can be easily discharged to the outside of the removing device 300 by opening the lower inlet 312, so that the adsorption filter medium can be easily replaced. Further, since only the adsorption filter medium is discharged at the time of replacement, the used adsorption filter medium can be easily heated and regenerated.

The gaseous impurity removing apparatus 300 according to the present embodiment is provided with a duct portion arranged in the horizontal direction,
Alternatively, it is preferable that the adsorption filter medium is arranged in the duct portion so as to incline slightly from the horizontal direction in the vertical direction, and it is not suitable for installation in the duct arranged in the vertical direction because the replacement work of the adsorption filter medium becomes rather complicated.

FIG. 7 shows an air cleaning system 400 including the gaseous impurity removing devices 100 and 300 configured as described above. This air cleaning system 400
Is applied to a clean room 402 for storing LCD substrates as shown in the figure. A filter device 404 for removing particles that does not generate organic contamination from itself is installed on the ceiling of the clean room 402, as described later, and clean air can be supplied to the room. Clean room 4
02 floor is configured as a grating floor 408,
It is possible to sequentially exhaust air to the outside of the room. The exhausted air is sent to the gaseous impurity removing apparatus 100 (300) configured according to the present invention by the blower 412 installed in the duct 410 forming the circulation path, and after the gaseous impurities are removed. Then, it is circulated in the clean room 402 through the particle removing filter 404 again.

If the air to be treated contains a lot of fine particles as dust, in order to remove the fine particles contained in the air to be treated, the gaseous impurity removing device 10 is used.
A filter device (not shown) capable of removing fine particles in the air stream can be provided on the upstream side of 0 (300). Further, the particles scattered from the gaseous impurity removing apparatus 100 (300) itself are provided with a particle removing filtering device 4 installed on the downstream side thereof.
Captured and removed by 04. The removal device 100
Regarding the filtering device 404 installed on the downstream side of (300), the binder, non-woven fabric, gasket, etc., which are the constituent members of the filtering device, are all made of impurities such as organic substances so that the filtering device itself does not become a secondary pollution source. It must be composed of non-occurring materials.

Filtering device 4 which does not generate such organic contaminants
As an example of forming 04, first, glass fibers are woven into a pleated filter using a glass spacer.
Next, the filter end portion is sandwiched between the metal frames by using the woven cloth of micro glass fiber as a sealing material. This filter is baked together with the metal frame at 300 ° C. to remove all organic substances. In the illustrated example, the filtration device 404 is mounted in the storage 402, but it is preferable to use Teflon packing that does not generate organic gas as the seal of the mounting portion.

[0032]

EXAMPLE An example in which the impurity removing apparatus according to the present invention is applied to the air cleaning system shown in FIG. 7 will be described below. The adsorption filter medium used in this example has a diameter of 2 mm.
Based on the spherical activated carbon of No. 3, as described below, various chemicals are impregnated depending on the type of impurity gas to be removed.

1) When the gas to be removed is an organic substance, it is not necessary to attach a chemical.

2) When the gas to be removed is an acid gas, potassium carbonate may be impregnated. It is removed by chemisorption due to neutralization reaction. 2HCl + K ₂ CO ₃ → 2KCl + CO ₂ + H ₂ O (hydrochloric acid) 2HF + K ₂ CO ₃ → 2KF + CO ₂ + H ₂ O (hydrogen fluoride) 2HNO ₃ + K ₂ CO ₃ → 2KNO ₃ + CO ₂ + H ₂ O (nitric acid) H ₂ SO ₄ + K ₂ CO ₃ → KHSO ₄ + KHCO ₃ K ₂ SO ₄ + CO ₂ + H ₂ O (sulfuric acid)

3) When the gas to be removed is an alkaline gas, phosphoric acid may be impregnated. It is removed by chemisorption due to neutralization reaction. NH ₃ + H ₃ PO ₄ → NH ₃ + H ₃ PO ₄ NH ₄ H ₂ PO ₄ + NH ₃ → (NH ₄ ) ₂ HPO ₄ (NH ₄ ) ₂ HPO ₄ + NH ₃ → (NH ₄ ) ₃ PO ₄ (ammonia)

4) When the gas to be removed is a sulfur-based gas,
It suffices to impregnate potassium permanganate. It is removed by chemisorption due to neutralization reaction. _{3SO 2 + 2KMnO 4 + 4KOH →} 3K 2 SO 4 + 2MnO 2 + 2H 2 O MnO 2 + SO 2 + 2KOH → K 2 SO 4 + MnO + H 2 O (SO 2) 2MnO + O 2 → 2MnO 2 3H 2 S + 2KMnO 4 → 3S + 2MnO 2 + 2KOH + 2H 2 O (H 2 S)

Such spherical activated carbon having a diameter of 2 mm was packed in a rectangular parallelepiped container made of stainless steel having a length and width of 500 mm × 500 mm and a width of 40 mm. 500 mm x 500 m
The two opposite surfaces of m are made of a mesh made of stainless steel with a mesh of 1.5 mm that allows ventilation. As shown in FIG. 1 and FIG. 2, seven rectangular parallelepiped containers packed with spherical activated carbon are
Dimensions 500 mm in height and 490 mm in width were arranged in parallel in the width direction at equal intervals in the duct. The gap between the rectangular parallelepiped containers at both ends and the duct wall was 15 mm, and the gap between the adjacent rectangular parallelepiped containers was 30 mm. The device for removing gaseous impurities in the air is made of a material that does not generate organic substances, and its mounting seal portion also uses Teflon that does not generate organic substances.

A device for removing such gaseous impurities in air is
It was applied to supply air without gaseous impurities to the storage of the LCD substrate (internal volume 30 m ³ ) shown in FIG. 7. All the constituent members of the storage cabinet itself were made of materials that did not generate impurity gas. For example, metal such as stainless steel,
Glass was used for the member requiring transparency. In addition, Teflon packing that does not generate organic gas is used in all parts where sealing is required, for example, the joint part of the metal plate and the frame part of the glass window.

Here, the main flow velocity in the duct is 0.5 m /
s, the flow rate was 0.12 m ³ / s (74 m ³ / min), and the storage ventilation rate was 0.25 times / min. On the contrary,
The total ventilation area of the seven rectangular parallelepiped containers is 1.75 m ^2, which is 7 times the duct cross-sectional area of 0.25 m ² . That is, a ventilation air velocity of 7.1 cm / s which penetrates the adsorption filter medium in the rectangular parallelepiped in the width direction, and the contact time of the air to be treated with the adsorption filter medium is 0.56 seconds.

In order to examine the effectiveness of the device for removing gaseous impurities in air according to the present embodiment, spherical activated carbon having a diameter of 2 mm, which is not impregnated with chemicals, is used and the storage is constructed as shown in FIG. The manner of contamination of the surface of the glass substrate placed on the grating of the cabinet with organic substances was examined. Glass substrate is CO
RNING # 7059, 100mm x 100mm x
It is 1.1 mm ^t . After removing all organic substances adhering to the surface of the glass substrate by UV / ozone cleaning, they were subjected to a test and evaluated by a contact angle evaluation method.

The results are shown in FIGS. 9 and 10. In the graphs shown in FIGS. 9 and 10, the vertical axis represents the contact angle,
The horizontal axis shows the exposure time. In this example, in order to evaluate the contamination state of the glass substrate surface,
The contact angle evaluation method was used. The contact angle measured by the contact angle evaluation method is the contact angle of the ultrapure water droplets dropped on the surface of the glass substrate, and the state of contamination of the glass surface with the organic matter (carbon / carbon) measured by XPS (X-ray photoelectron spectroscopy). There is a relationship between the silicon ratio) and the contact angle as shown in FIG. carbon/
The silicon ratio is an index that is proportional to the amount of organic substances attached to the surface, and the contact angle is an index that represents the degree of contamination by hydrophobic organic substances on the surface. Therefore, by observing the contact angle, the state of organic substance contamination on the surface of the glass substrate can be measured simply and in a short time. Since the contact angle measuring method is not directly related to the present invention, its detailed description is omitted. For details, refer to Japanese Patent Application No. 7-171373 filed by the same applicant as the present applicant.

The graph shown in FIG. 9 shows the change over time in the contact angle of the glass surface, the glass substrate immediately after cleaning being filled with air from the device for removing gaseous impurities in air according to the present invention. This is a comparison between the case where the glass substrate is placed in a refrigerator and the case where the glass substrate is placed in a normal clean room atmosphere. As is clear from FIG. 9, it is understood that the performance of the adsorption filter medium deteriorates after the exposure time exceeds 120 days. So, in the actual production line,
When storing the LCD substrate, it is preferable to replace the rectangular parallelepiped container filled with the spherical activated carbon attached to the removing device of the present invention every three months. FIG. 10 shows the time-dependent change in the contact angle of the LCD substrate immediately after cleaning for about 10 months. It can be seen that the contact angle increases only once every 3 months. The apparatus for removing gaseous impurities in air according to the present invention is LC
It could be effectively applied to the D substrate storage, and a sufficient surface contamination preventing effect could be obtained.

The preferred embodiments of the gaseous impurity removing apparatus and the air cleaning system constructed according to the present invention have been described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to such examples. Yes. It is obvious that those skilled in the art will come up with various variations and modifications within the scope of the technical idea described in the claims, and these also belong to the technical scope of the present invention. Understood.

For example, although the description has been given in connection with the example in which the gaseous impurity removing apparatus according to the present invention is applied to the storage for the LCD substrate in the above embodiment, the present invention can be applied to various clean rooms. is there. Further, the air path circulating in the gaseous impurity removing apparatus according to the present invention,
The zigzag-shaped air path has been shown as long as it passes through at least one filter medium, and in particular, a surface parallel to the air flow direction in the duct is formed as a ventilation surface, but the present invention is not limited to such an example, and for example, in a duct The surface of the adsorption filter medium unit facing upstream may be configured as a ventilation surface. In this case, when the casing is configured as a rectangular parallelepiped, at least three surfaces are configured as ventilation surfaces.

[0045]

As described above, the apparatus for removing gaseous impurities according to the present invention remarkably lowers the ventilation wind velocity of the adsorption filter medium as compared with the mainstream wind velocity in the duct, and maintains low pressure loss and high adsorption performance. Is possible. Further, the device for removing gaseous impurities according to the present invention can easily perform the replacement work even when the adsorption filter medium is frequently replaced by setting a short filter life in consideration of a high safety factor. It is possible. Furthermore, the device for removing gaseous impurities according to the present invention can be configured as a reusable device that can easily regenerate an adsorbent filter medium by heating, and a system excellent in resource saving can be constructed. . Furthermore, if the constituent members other than the adsorptive filter medium constituting the removing device according to the present invention are made of materials that do not generate gaseous impurities, a clean system can be constructed in which the removing device itself does not become a secondary pollution source.

[Brief description of drawings]

FIG. 1 is a schematic sketch showing an embodiment of a gaseous impurity removing apparatus according to the present invention.

FIG. 2 is a schematic plan view of the gaseous impurity removing apparatus shown in FIG.

FIG. 3 is a schematic diagram showing a schematic configuration of an adsorption filter medium unit applicable to the gaseous impurity removing apparatus shown in FIG.

FIG. 4 is a cross-sectional view taken along the line AA ′ of the adsorption filter medium unit shown in FIG.

FIG. 5 is a schematic sketch showing another embodiment of the gaseous impurity removing apparatus according to the present invention.

FIG. 6 is a schematic plan view of the gaseous impurity removing apparatus shown in FIG.

FIG. 7 is a schematic view of a device for removing a gaseous impurity according to the present invention as an LCD.
It is a schematic system block diagram which shows one Embodiment of the air purifying system applied to the substrate storage.

FIG. 8 is a graph showing the relationship between the contact angle in the contact angle determination method and the organic contamination state of the glass substrate.

FIG. 9 is a graph showing changes over time in the contact angle of the glass surface placed in an air supply atmosphere from the device for removing gaseous impurities in air according to the present invention and in a normal clean room atmosphere.

FIG. 10 is a graph showing changes over time in the contact angle of the LCD substrate placed in the LCD substrate storage.

[Explanation of symbols]

 100 Gaseous Impurity Removal Device 102 Duct 104 Lid 200 Adsorption Filter Media Unit 202 Casing 202a Vent Surface 204 Adsorption Filter Media 206a-206d Blind Plate 208a-208d Blind Plate

Claims (8)

[Claims] 1. A device for removing gaseous impurities inserted in a duct path, wherein a plurality of sets of adsorption filter medium units capable of removing gaseous impurities are spaced apart from each other and are substantially parallel to the main flow direction in the duct. A device for removing gaseous impurities, which is arranged and in which an air path is formed so that treated air passes through at least one adsorption filter medium unit. 2. The adsorption filter medium unit is composed of an adsorption filter medium and a casing, and a ventilation path is formed between at least adjacent casing surfaces facing each other. Gaseous impurities removal device. 3. The space formed between the adsorption filter media units is closed and opened repeatedly between adjacent spaces on the upstream side of the duct, and is closed on the upstream side on the downstream side of the duct. The device for removing gaseous impurities according to claim 1 or 2, characterized in that the gap is opened, and the gap opened on the upstream side is closed. 4. The gaseous state according to any one of claims 1 to 3, wherein each of the adsorption filter medium units is detachable via a lid portion of the duct which is configured to be openable and closable. Impurity remover. 5. The casing is formed integrally with a duct path, and the filter medium is filled in the casing through an inlet provided vertically above the duct path and vertically below the duct path. The gaseous impurity removing device according to any one of claims 1 to 3, wherein the gaseous impurity removing device can be discharged to the outside of the casing from an outlet provided in the. 6. The gaseous impurity removing apparatus according to claim 1, wherein the casing is made of an inorganic material. 7. An air cleaning system comprising the gaseous impurity removing device according to claim 1, wherein a first stream of particles in an air stream is removable upstream of the gaseous impurity removing device. A second filter capable of removing at least particles from the adsorbent filter medium of the gaseous impurity removing device is provided downstream of the gaseous impurity removing device while the filtering device is provided.
An air purifying system, characterized in that the filter device is provided. 8. The air cleaning system according to claim 7, wherein the second filtering device is made of a material that does not generate an impurity gas.