JP2010017713A - Fluid cleaning apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid cleaning apparatus that can stably supply a very clean fluid for a long period by making the best use of the adsorption capacity of an adsorbent filter used in the fluid cleaning apparatus. <P>SOLUTION: The fluid cleaning apparatus includes a photocatalyst unit 2 for decomposing contaminants in a fluid to be treated and an adsorbent filter unit 3 for adsorbing contaminants in a fluid to be treated. The photocatalyst unit 2 is located upstream from the adsorbent filter unit 3 in the flow direction of the fluid to be treated. The fluid cleaning apparatus further includes a dust removal filter unit 9 located downstream from the adsorbent filter unit. The switching means 11, 12, 13 and 14 for selectively introducing the fluid to be treated to the photocatalyst unit or the adsorbent filter unit can give more effect on the performance. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention uses a photocatalyst and an adsorbent filter to remove pollutants in a gas or liquid by efficiently decomposing and adsorbing them, and to supply a clean fluid over a long period of time. The present invention relates to a fluid purification device that can be suitably used as a device.

  In recent years, semiconductor devices have become highly integrated and high quality, and in the case of fine pollutants that cannot be removed by high performance dust filters (generally known as HEPA filters or ULPA filters), such as gases, organic Contaminants at the molecular level such as gas, inorganic gas, and ozone gas have become a problem as a cause of device manufacturing defects.

  It is known to remove contaminants such as organic gas, inorganic gas, ozone gas and the like with an adsorbent. As an adsorbent, an adsorbent filter (commonly known as a chemical filter) composed of activated carbon, activated carbon impregnated with a neutralizing reactant, or an ion exchange group such as an ion exchange fiber is provided.

  In the removal of contaminants by the adsorbent filter, for example, organic gas or ozone gas is removed by physical adsorption or decomposition with granular or fibrous activated carbon or the like. The acidic gas is removed by chemical adsorption with granular or fibrous activated carbon impregnated with potassium carbonate, or ion exchange with ion exchange groups such as ion exchange fibers. Alkaline gas is chemically adsorbed by granular or fibrous activated carbon impregnated with phosphoric acid, or ion exchanged by ion exchange groups such as ion exchange fibers and removed. These adsorbent filters are generally composed of layered elements and are used as a unit including one layer or a combination of two or more layers.

  The adsorption efficiency of the adsorbent filter decreases as the amount of adsorbed contaminants approaches saturation, and when the adsorbent filter is completely saturated, it is necessary to replace the adsorbent filter. In adsorbent filters composed of activated carbon, neutralized reactants attached to activated carbon, or ion exchange groups such as ion exchange fibers, organic substances with a relatively low molecular weight, that is, organic substances with a low boiling point, saturate the adsorbent filter. When approaching, it passes without adsorbing, or there is a problem that adsorption capacity is lost due to repeated adsorption and desorption. On the other hand, it is excellent for adsorption of organic substances having a relatively high molecular weight, that is, organic substances on the high boiling point side, and can be adsorbed for a relatively long period of time without desorption after saturation.

  Although the replacement cycle of the adsorbent filter varies depending on the contaminated environment, it is about 0.5 to 2 years in a general semiconductor device factory, and an adsorbent filter unit having a longer life is desired.

  It has also been proposed to apply a photocatalyst to the removal of contaminants at the molecular level (for example, JP-A-2001-62253). When using a photocatalyst, the contaminant is removed by oxidative decomposition by photocatalysis. The photocatalyst is excellent in decomposing an organic substance having a relatively small molecular weight, that is, an organic substance having a low boiling point. A photocatalyst unit that removes contaminants by photocatalysis includes a photocatalyst (for example, titanium oxide) supported on the surface of a support and an excitation light source that emits ultraviolet light that excites the photocatalyst.

  In the photocatalyst unit, since the life of the lamp of the excitation light source and the like itself are deteriorated, it is necessary to periodically clean or replace them. In addition, since a support such as a glass material exposed to a contaminant gradually becomes contaminated, it must be cleaned or replaced.

  In JP-A-11-123316, a particle filtration layer, a photocatalyst holding layer, an ion exchange fiber packed layer (or an activated carbon fiber packed layer, or a mixed packed layer of ion exchange fibers and activated carbon fibers) are coated in this order. An ultra-clean air production device is described that purifies through process air. In this apparatus, the particle filtration layer is in front (upstream side) of the photocatalyst holding layer and the ion exchange fiber packed layer, and it is described that the air to be treated is selectively introduced into the photocatalyst holding layer or the ion exchange fiber packed layer. It has not been.

  Japanese Patent Application Laid-Open No. 11-300150 describes an air cleaning filter using a chemical adsorbent, a physical adsorbent and a photocatalyst and having an excellent deodorizing function for mounting on a vehicle. The chemical adsorbent, physical adsorbent and photocatalyst are not individually unitized but are substantially integrated. The air to be treated cannot be selectively supplied to the adsorbent and the photocatalyst.

  Japanese Patent Application Laid-Open No. 11-47256 discloses a deodorizing apparatus in which a gas adsorbing filter and a photocatalyst are arranged in this order. If a dust collection filter is used, it is placed further in front of the gas adsorption filter. There is no description of selectively supplying air to the adsorbent and photocatalyst.

  Japanese Patent Application Laid-Open No. 2001-232154 describes a deodorizing device in which two types of activated carbon (adsorbent) and a photocatalyst are supported on a filter as a supporting means. The activated carbon adsorbent and the photocatalyst are supported on the same filter, and the air to be treated cannot be selectively introduced into each of them.

JP 2001-62253 A JP-A-11-123316 Japanese Patent Laid-Open No. 11-300150 JP 11-47256 A JP 2001-232154 A

  As described above, there is a demand for a fluid purification device that can stably supply a purified fluid even after the adsorbent filter approaches a saturated state. In particular, there is a need for a technique for maintaining an environment such as a clean room that requires a high degree of cleanliness, which is essential for manufacturing electronic devices, at a stable cleanness.

  An object of the present invention is to provide a fluid purification device that makes it possible to stably supply a highly clean fluid over a long period of time by making maximum use of the adsorption capacity of the adsorbent filter used in such a fluid purification device. It is to be.

  In one aspect, the fluid purification device of the present invention is a device that removes contaminants from a fluid to be treated, which is a fluid that mainly flows into a sealed environment such as a clean room, and removes contaminants in the fluid to be treated. A photocatalytic unit having a decomposable photocatalyst and an excitation light source for exciting the photocatalyst, and an adsorbent filter unit capable of adsorbing contaminants in the fluid to be treated, the photocatalytic unit being arranged in the flow direction of the fluid to be treated It is characterized by including a dust removing filter unit disposed on the upstream side of the adsorbent filter unit and further disposed on the downstream side of the adsorbent filter unit.

  In another aspect, the fluid purification device of the present invention is a device for removing contaminants from a fluid to be treated, which is a photocatalyst capable of decomposing contaminants in the fluid to be treated, and an excitation light source for exciting the photocatalyst. A photocatalyst unit having an adsorbent filter unit capable of adsorbing contaminants in the fluid to be treated, the photocatalyst unit being disposed upstream of the adsorbent filter unit with respect to the flow direction of the fluid to be treated, and It includes switching means for selectively introducing the fluid to be treated into the photocatalyst unit or the adsorbent unit.

  According to the present invention, the efficient use of a photocatalyst makes it possible to use a fluid removal apparatus that extends the life of an adsorbent filter and increases the efficiency of removing contaminants, and is indispensable for environmental control including clean rooms. Environmental control of the space can be facilitated.

It is a figure which illustrates typically the gas chromatogram obtained about various gas. It is a figure which shows typically the combination of the photocatalyst unit and adsorbent filter unit which are used with the fluid purification apparatus of this invention. It is a figure explaining the one aspect | mode of the fluid purification apparatus of this invention. It is a figure which shows the example of the usage condition of the fluid purification apparatus of this invention. It is a figure explaining another aspect of the fluid purification apparatus of this invention. It is a figure explaining another aspect of the fluid purification apparatus of this invention. It is a figure explaining another aspect of the fluid purification apparatus of this invention. It is a figure explaining another aspect of the fluid purification apparatus of this invention. It is a figure which shows the example which used the fluid purification apparatus of this invention for the environmental control in a clean booth. It is a figure which shows the example which used the fluid purification apparatus of this invention for the environmental control of the opening part of a SMIF-box.

  In the fluid purification apparatus of the present invention, a combination of a photocatalyst unit and an adsorbent filter unit is used. Both of these enable the removal of fine, molecular level contaminants that cannot be removed with high performance dust filters such as HEPA filters and ULPA filters.

  The photocatalyst contained in the photocatalyst unit is particularly excellent for decomposing an organic substance having a relatively small molecular weight, that is, an organic substance having a low boiling point. By first treating the fluid to be treated containing the pollutant with the photocatalytic unit, it is possible to selectively decompose and remove low boiling point organic substances having a relatively small molecular weight. High-boiling organic substances having a relatively large molecular weight that are difficult to be decomposed by the photocatalyst pass through (or bypass) the photocatalyst unit, reach the adsorbent filter unit, and are removed by being adsorbed by the adsorbent filter.

  The important point in the fluid purification apparatus of the present invention is that the fluid to be treated is treated in the order of the photocatalyst unit and the adsorbent filter unit to remove contaminants. By keeping this order, contaminants having a large molecular weight can selectively flow through the adsorbent filter unit, and the adsorption capability of the adsorbent filter can be maintained for a long time. If this order is reversed and the fluid to be treated is supplied to the adsorbent filter unit first, the adsorbent filter adsorbs contaminants regardless of the molecular weight, so the adsorbent filter is saturated with contaminants with low molecular weight. Until it is absorbed, the adsorption capacity of pollutants with a large molecular weight is reduced accordingly.

The photocatalyst unit used in the present invention includes a photocatalyst and an excitation light source for exciting the photocatalyst. As an example, the photocatalyst is used by being supported on a transparent support such as a glass material. A typical photocatalyst is titanium oxide (TiO ₂ ), which is excited by ultraviolet irradiation to oxidatively decompose low molecular weight contaminants such as acetone, methanol, ethanol, methyl ethyl ketone, and the like.

  As the excitation light source, an ultraviolet lamp that emits light effective for excitation of the photocatalyst or a light emitter by discharge can be used. The excitation light source may be arranged in the same atmosphere together with the photocatalyst, or may be installed separately from the atmosphere where the photocatalyst is located. In the former case, the excitation light source is exposed to the flow of the process fluid along with the photocatalyst and is positioned relatively adjacent to the photocatalyst. In the latter case, the excitation light source is separated from the photocatalyst through a light-transmitting partition such as quartz glass and does not come into direct contact with the fluid to be treated containing contaminants.

  The photocatalyst is selected according to the type of contaminant to be treated, and the light source for exciting it is selected according to the type of photocatalyst selected. In the case of titanium oxide, which is a typical photocatalyst, a lamp that emits ultraviolet rays having a wavelength band of 150 to 450 nm or a light emitter by discharge can be preferably used.

  Photocatalytic units are widely known and need not be further described here, but as an example, a thin film of titanium oxide was formed on the inner surface or inner and outer surfaces of a glass tube as disclosed in JP-A-2001-62253. The thing using a photocatalyst can be mentioned.

  The adsorbent filter unit is composed of layered elements including activated carbon, a neutralized reactant attached to the activated carbon, ion exchange groups such as ion exchange fibers, or a combination thereof. As an adsorbent filter, what is supplied with the name of a chemical filter, for example can be used. For example, granular or fibrous activated carbon is suitable for organic gas removal or ozone gas decomposition by physical adsorption, and granular or fibrous activated carbon impregnated with potassium carbonate or the like is suitable for removal of acidic gas by chemical adsorption. Is suitable. The acid gas may be removed by ion exchange using an adsorbent filter using ion exchange groups such as ion exchange fibers. Alkaline gas can be removed by chemical adsorption with granular or fibrous activated carbon impregnated with phosphoric acid, or ion exchange with ion exchange groups such as ion exchange fibers.

  Although the adsorbent filter can remove contaminants at the molecular level that cannot be removed by a high-performance dust filter such as a HEPA filter or ULPA filter, when the adsorption of contaminants approaches saturation, the size of the contaminant molecules Therefore, a difference occurs in the adsorption performance. Tables 1 and 2 show the adsorption performance of various pollutant molecules.

Table 1 shows the adsorption performance of the adsorbent filter at the start of adsorption. Each contaminant molecule shown in this table is adsorbed and held by the adsorbent filter. Table 2 shows the adsorptivity when the adsorption proceeds and approaches saturation. The compounds in the leftmost column of the table are not captured by the adsorbent filter and begin to pass through. These are compounds having a relatively small molecular weight. The compounds in the second and third columns from the left of the table are adsorbed but may later desorb and leak out of the adsorbent filter. The compounds in the rightmost column of the table remain adsorbed and retained by the adsorbent without desorption. These are compounds having a relatively large molecular weight. (In Tables 1 and 2, D2 to D6 are basic structural units —Si (CH ₃ ) ₂ O— each having 2 to 6 silicone compounds, MEK is methyl ethyl ketone, IPA is isopropyl alcohol, PGMEA is propylene glycol monomethyl ether acetate, (PGME represents propylene glycol monomethyl ether, NMP represents N-methylpyrrolidone, DBP represents dibutyl phthalate, DOP represents dioctyl phthalate, and TBP represents tributyl phosphate.)

  As is clear from these tables, contaminants having a relatively low molecular weight, that is, low-boiling contaminants, pass through without being adsorbed when the adsorbent filter approaches saturation, or repeatedly adsorb and desorb, thereby The adsorption capacity of the adsorbent filter is easily lost. On the other hand, organic substances having a relatively large molecular weight, that is, contaminants having a high boiling point can continue to be adsorbed for a relatively long period of time, and are hardly desorbed even after saturation.

  For example, the type and amount of pollutants contained in a fluid to be treated (air containing pollutants) handled by a fluid purification device used as an environment control device for maintaining a clean room environment varies with time. If the treated fluid contains both relatively low molecular weight contaminants that are less likely to be trapped by the adsorbent filter when close to saturation and relatively high molecular weight contaminants that are trapped by the adsorbent filter even when close to saturation, When the treatment fluid is flowed in the order of the photocatalyst unit and the adsorbent filter unit in accordance with the present invention, the low molecular weight contaminants in the treated fluid are decomposed and removed by the photocatalyst, so the adsorbent filter unit removes the treated fluid containing the high molecular weight contaminants Can be processed. As a result, low molecular weight contaminants that are not necessarily suitable for adsorption removal by the adsorbent filter without the photocatalytic unit do not reach the adsorbent filter unit. In particular, all can be devoted to high molecular weight contaminants suitable for adsorption removal there. This also leads to extending the useful life of the adsorbent filter.

  When the fluid to be treated contains exclusively low molecular weight contaminants, the contaminants are decomposed and removed by the photocatalyst unit, and the adsorbent filter unit is operated substantially without load. In such a case, the fluid to be treated can bypass the adsorbent filter unit after the treatment with the photocatalytic unit.

  If the fluid to be treated contains exclusively high molecular weight contaminants, the contaminants pass through the photocatalyst unit to the adsorption filter unit without being substantially treated, and are adsorbed and removed there. In such a case, the fluid to be treated can bypass the photocatalytic unit. This bypass is advantageous in that it eliminates the possibility of the photocatalytic unit being contaminated with contaminants that cannot be resolved and removed there.

  A dust removal filter unit can be disposed downstream of the adsorption filter unit. This unit is not limited to particulate contaminants originally contained in the fluid to be treated introduced into the environmental control device, but also particulate foreign matters (for example, from the adsorbent filter) generated during processing in the environmental control device. It also allows for the supply of clean fluids that are free from all types of contaminants. As the dust removal filter, a HEPA filter, a ULPA filter, or the like widely used in clean room air purification can be used.

  The fluid purification apparatus of the present invention can include a fluid transfer means that enables transfer of a fluid to be processed. When the fluid to be processed is a gas, a fan can be used as this means. Preferably, the fan is unitized and integrated with the dust filter unit if it includes a photocatalyst unit, an adsorbent filter unit, and a dust filter. The fan may be installed separately from other units due to the installation conditions of the device. When the fluid to be processed is a liquid, a pump is generally used as the fluid transfer means. Pumps can also be unitized and integrated with other units or installed separately from them.

  Using the component devices (photocatalyst, adsorbent filter, dust filter, fluid transfer means) unitized (or modularized) in the fluid purification apparatus of the present invention makes it easy to manufacture, assemble, maintain and inspect. There is an advantage. For example, the filter element can be easily replaced by making the adsorbent filter unit and the dust removal filter unit so that the filter element can be attached and removed in a pull-out manner.

  The fluid purification device of the present invention can also include an analyzer (measurement monitor) that analyzes one or both of the contaminants of the fluid to be treated introduced into the device and the fluid purified by the device. Switching for selective introduction of the fluid to be treated into the photocatalyst unit or the adsorbent filter unit described above can be performed using analysis data from an analyzer provided on the inlet side to the fluid purification apparatus. Furthermore, if an analyzer provided on the outlet side of the fluid purification apparatus is used, it is possible to return the fluid to the upstream side for reprocessing when contaminants are still detected in the processed fluid. As the analyzer, a known analytical instrument that is effective for detecting a contaminant assumed to be contained in a fluid to be processed by the fluid purification device can be used.

  As an example, analysis using gas chromatography will be described. Using a sample on the upstream side of the fluid purification device, that is, the inlet side of the fluid to be treated, containing a low-boiling contaminant such as acetone or MEK and a high-boiling contaminant such as DBP or DOP. When analyzed by gas chromatograph, a gas chromatogram including both the peak of the low boiling point component and the peak of the high boiling point component as shown in FIG. 1 (a) is obtained. At this time, the fluid to be treated is the photocatalyst unit and the adsorbent. It is purified through both filter units.

  As shown in FIG. 1 (b), when a low boiling point component is detected in the sample on the upstream side of the fluid purification device, the fluid to be treated is treated with the photocatalytic unit and comes out of the photocatalytic unit. In some cases, the fluid may be bypassed without passing through the adsorbent filter unit. On the other hand, as shown in FIG. 1 (c), when a high boiling point component is detected in the sample on the upstream side of the fluid purification device, the fluid to be treated is directly passed to the adsorbent filter unit by bypassing the photocatalytic unit. It is possible to introduce. FIG. 1 (d) shows a gas chromatogram obtained on the outlet side of the fluid purification device, in which only the background response is recorded and no peak corresponding to the contaminant is seen. When a peak indicating that a part of the contaminant is contained in the fluid from the purification device is observed in the gas chromatogram, the fluid can be returned to the upstream side of the purification device.

  The change of the destination of the fluid to be processed or the processed fluid may be performed manually or automatically. In the automatic case, a control unit can be used that processes the signal from the analyzer and generates a signal that automatically changes.

  Next, although the fluid purification apparatus of this invention is further demonstrated with reference to drawings, this invention is not limited to them.

  FIG. 2 is a schematic view showing a combination of the photocatalyst unit 2 and the adsorbent filter unit 3 used in the fluid purification apparatus of the present invention. As the fluid to be treated, for example, a gas typified by air in a clean room can be used, or pure water used in a semiconductor device production facility may be used. The fluid to be processed passes through this combination in the order of the photocatalytic unit 2 and the adsorbent filter 3.

The photocatalyst unit 2 includes an ultraviolet lamp having a wavelength band of 150 to 450 nm or a light emitter 4 accompanying discharge, and a photocatalyst 5 such as TiO ₂ supported on a support surface such as a glass material. Can be manufactured, for example, having a structure as disclosed in Japanese Patent Application Laid-Open No. 2001-62253.

  The adsorbent filter unit 3 uses an adsorbent filter suitable for adsorbing and removing contaminants in the fluid to be treated, such as activated carbon, a neutralized reactant attached to the activated carbon, or an ion exchange group such as an ion exchange fiber. Produced.

  This combination can be used to remove contaminants such as inorganic or organic gases and ozone gas.

  Adsorbent filters are usually based on activated carbon and tend to lose their ability to capture from relatively low molecular weight organics such as acetone, methanol, ethanol, etc. It is in. For example, an adsorbent filter with a neutralization reactant attached can adsorb organic substances with a low molecular weight such as acetone, methanol, and ethanol before the adsorbent filter is saturated as the adsorption amount increases. As a result, these substances pass through the adsorbent filter unit. Organic substances such as acetic acid, formic acid, and isopropyl alcohol (IPA), which have a slightly higher molecular weight than these, may be desorbed after being adsorbed. Therefore, it cannot be said that these relatively low molecular weight organic substances are so suitable for complete removal with an adsorbent filter.

  On the other hand, the photocatalyst unit 2 decomposes pollutants by photocatalysis, and is excellent in decomposing organic substances having a low molecular weight such as acetone, methanol, and ethanol, that is, low-boiling organic substances. There is a problem in terms of decomposition efficiency in the decomposition of organic substances having a relatively large molecular weight, such as organic substances having a high boiling point.

  Therefore, for example, organic substances having a small molecular weight such as acetone, methanol, and ethanol, and organic substances such as acetic acid, formic acid, and isopropyl alcohol having a slightly higher molecular weight than these are first decomposed and removed by the photocatalytic unit 2. Next, the adsorbent filter unit 3 adsorbs and removes organic substances having a relatively large molecular weight, such as xylene, ethylbenzene, and cyclohexanone, which could not be decomposed and removed by the photocatalyst unit 2, so The processing fluid can be efficiently processed and purified. Further, since the adsorbent filter unit 3 can be dedicated to the adsorption and removal of contaminants having a relatively large molecular weight, the adsorption capability of the adsorbent filter can be maintained for a long time.

  The operating conditions for effectively operating the photocatalyst unit 2 and the adsorbent filter unit 3 can be determined depending on the type of photocatalyst and adsorbent filter used in them.

FIG. 3 shows an embodiment of the fluid purification device of the present invention that incorporates the combination of the photocatalyst unit 2 and the adsorbent filter unit 3 shown in FIG.
The apparatus 1 of this aspect is configured by integrally arranging a photocatalyst unit 2, an adsorbent filter unit 3, a fluid transfer means unit 8, and a dust removal filter unit 9 in this order, and the fluid to be treated is on the photocatalyst unit 2 side. Enters the device 1 and the purified fluid exits the dust removal filter unit 9. Such an apparatus 1 is provided, for example, on the wall surface or ceiling surface of a clean room, or the wall surface or ceiling surface of a production facility such as a semiconductor device, and is used to clean the air in the clean room as a fluid to be processed. can do. When it is difficult to integrate the units due to restrictions on the installation location, it is possible to install them separately without being adjacent to each other.

  In the apparatus 1 shown in FIG. 3, as the fluid transfer means of the unit 8, a fan can be used when the fluid to be processed is a gas, and a pump can be used when the fluid to be processed is a liquid. The unit 8 in the case where the fluid transfer means is a fan is not limited to between the adsorbent filter 3 and the dust removal filter 9 shown in the figure, and may be disposed, for example, upstream of the photocatalytic unit 2. It is also possible to arrange them at positions separated from the combination of 3 and 9. Also in this case, the fluid transfer means unit 8 is connected to, for example, the upstream side of the photocatalytic unit 2, or the suction side is connected to the outlet side of the adsorbent filter unit 3, and the discharge side is connected to the inlet side of the dust filter. It is possible to connect. The unit 8 in the case where the fluid transfer means is a pump can also be arranged at an arbitrary position, but is preferably arranged upstream of the photocatalytic unit 2. Whether the fluid to be treated is a gas or a liquid, the fluid transfer means is a potential source of contamination, so the unit 8 is preferably installed upstream of the dust removal filter unit 9.

  4 (a) to 4 (c) exemplify a representative positional relationship between the purification device 1 and the environment to be controlled when the fluid purification device 1 of the present invention is used as an environment control device. . FIG. 4A is an example in which the purification device 1 is installed on the ceiling of the closed system manufacturing device or work booth 11, and the working environment in the manufacturing device or work booth 11 is sent by sending the air purified by the purification device 1. Can be kept clean. FIG. 4B is an example in which the purification device 1 is installed adjacent to a closed system manufacturing device or work booth 11 and is also used to keep the working environment in the manufacturing device or work booth 11 clean. be able to. This example can be adopted when there is no space for installing the purification device 1 on the ceiling of the manufacturing device or the work booth 11, and in some cases, the purification device 1 is directly connected to the wall of the manufacturing device or the work booth 11. It is also possible to install. In the examples of FIGS. 4A and 4B, if the manufacturing apparatus or the work booth 11 is replaced with a clean room, the work environment of the clean room can be controlled. FIG. 4C is an example in which the purification device 1 is incorporated into the exhaust system from the manufacturing apparatus or work booth 11 in the clean room, and the contaminants contained in the exhaust from the manufacturing apparatus or work booth 11 are removed. Can be used to prevent secondary contamination of clean rooms. In this case, the work environment in the clean room will be controlled cleanly, and as a result, FIG. 4 (a) or 4 (b) for supplying clean air to the manufacturing apparatus or the work booth 11 itself. As described above, it is possible to contribute to the improvement of the efficiency of another purification device (not shown) installed, or particularly to the extension of the life of the adsorbent filter unit.

  The purifying apparatus of the present invention is installed in a transport cart that requires a local clean storage unit for transporting wafers and the like, and this cart is replaced with a transport device for wafers and the like, which has conventionally been a box transport means. It can also be used.

  FIG. 5 shows, in addition to the photocatalyst unit 2, the adsorbent filter unit 3, the fluid transfer unit 8 including the fan, and the dust removal filter 9 described in the previous example, the pollutant concentration measurement monitor 15 for the gas to be processed, It can be used for environmental control of a clean room, which is composed of valves 11, 12, 13, 14 for switching the flow path of the gas to be processed and a control unit 16 for switching the valve according to the concentration of pollutants. 1 shows a fluid purification device 10 according to the present invention. The non-treatment gas in this case is air that may contain contaminants.

  For example, as the pollutant concentration measurement monitors 15 and 17, monitors that measure the amount of organic matter IPA, which is considered to be the cause of contamination by organic matter in a clean room, and organic matter cyclohexanone having a relatively small molecular weight. Is used.

  When the pollutant concentration measurement monitor 15 detects that IPA is contained in the air of the gas to be treated introduced into the clean room, the valve 11 is opened and the valve 12 is closed by the signal from the control unit 16, and the photocatalyst Unit 2 disassembles and removes IPA. The gas from which IPA has been removed by the photocatalytic unit 2 can also bypass the adsorbent filter unit 3 by closing the valve 13 and opening the valve 14 by a signal from the control unit 16. The gas from which IPA has been removed is then supplied into the clean room through the dust filter 9 by the fluid transfer unit 8.

  When IPA is not detected in the air of the gas to be treated and cyclohexanone is detected, the valve 11 is closed by a signal from the control unit 16 and the valve 12 is opened to bypass the photocatalyst unit 2 and adsorbent filter. Directly sent to the unit 3 to adsorb and remove cyclohexanone with an adsorbent filter.

  When both IPA and cyclohexanone are detected during the intake of the gas to be treated, the valves 11 and 13 are opened, the valves 12 and 14 are closed, and the IPA is decomposed and removed by the photocatalyst unit 2, and then the cyclohexanone is adsorbed. Adsorbed and removed by the filter unit 3.

  The photocatalyst unit 2 opens the valve 11 to receive the gas to be treated when an organic substance having a low molecular weight suitable for decomposition and removal with the photocatalyst is contained in the gas to be treated, and closes the valve 11 otherwise. Thus, the gas to be treated can be bypassed, which contributes to extending the life of the illuminant associated with the ultraviolet lamp or discharge of the excitation light source and reducing the number of periodic cleaning or replacement. Similarly, the number of periodic cleaning or replacement of the photocatalyst carried on the support can be reduced.

  Since the adsorbent filter unit 3 can always receive a gas without an organic substance having a low molecular weight, and can bypass a gas without an organic substance having a high molecular weight to be processed by this unit, the life of the adsorbent filter 3 can be increased. A reduction in the number of replacements of the adsorbent filter can be realized.

  The opening / closing control of the valves 11, 12, 13, 14 based on the measurement result of the pollutant concentration measurement monitor 15 may be performed manually without using the control unit 16.

  Furthermore, it is possible to additionally install a pollutant concentration measurement monitor 17 on the outlet side of the purification device 1. The measurement monitor 17 on the outlet side is effective as a means for confirming the lifetime of the photocatalyst unit 2 or the adsorbent filter unit 3. When a large amount of organic matter is detected, the photocatalyst unit 2 is selected according to the type of organic matter to be detected. Alternatively, it can be determined that the adsorbent filter unit 3 has deteriorated. The measurement result of the monitor 17 can be reflected in the change of the gas flow path by the control of the valves 11, 12, 13, and 14. Alternatively, it is possible to omit the pollutant concentration measurement monitor 15 on the inlet side of the purification apparatus 1 and provide only the measurement monitor 17 on the outlet side.

  By using the pollutant concentration measurement monitor 17 capable of measuring ozone gas, the purification device 10 can be used for purification of gas containing ozone. Since ozone oxidizes the surface of the semiconductor wafer, it must be removed efficiently. Ozone is reduced to oxygen by the adsorbent filter 3 and removed. However, since the photocatalyst functions as an oxidant, it can contribute to the generation of ozone, but cannot contribute to its removal. Therefore, when ozone gas is detected by the pollutant concentration measurement monitors 15 and 17, the valves 11, 13, and 14 are closed, and the valve 12 is opened. Since the gas containing ozone bypasses the photocatalyst unit 2 and flows to the adsorbent filter unit 3, ozone can be efficiently removed.

  Monitors that measure the total amount of organic substances may be used as the pollutant concentration measurement monitors 15 and 17, and the gas flow path may be changed based on the measurement results. This is because, for example, the type and amount of pollutants in a normal gas to be treated are determined, and as the other pollutants, substances that can be effectively treated with a photocatalyst are occasionally included in the gas to be treated. It is particularly effective in such cases.

  The pollutant concentration measurement monitors 15 and 17 may be installed when necessary, such as when fluctuations in the type and amount of pollutants in the gas to be treated are predicted. Further, the pollutant concentration measurement monitors 15 and 17 may be installed in another place without being provided in the gas flow path, and a sample collected from the gas flow path may be measured by a measurement monitor installed in another place.

  Furthermore, a damper or a slit-type opening / closing shutter can be used in place of the valves 11, 12, 13, and 14. Further, the valves 13 and 14 may not be provided, and a similar effect can be expected only by switching the valves 11 and 12.

  By installing the fluid purification devices 10 in multiple stages, more efficient purification can be performed. Further, if the fluid purification device 10 itself is placed in, for example, a stainless steel box, more efficient purification becomes possible.

  FIG. 6 shows a flow path from the outlet side of the dust filter unit 9 to the upstream side of the fluid purification apparatus, and valves 18 and 19 for switching to the circulation path in the fluid purification apparatus 10 described with reference to FIG. The fluid purification apparatus 10 'of the aspect which added these is shown. An example of purifying gas containing various pollutants using the purification apparatus 10 'will be described below.

  The first example is a crystal oscillator type that uses air containing contaminants such as acetic acid and formic acid, which cause oxidation of silicon wafers in the manufacture of semiconductor devices, as the gas to be processed, and measures the total amount of contaminants (TOC). The film thickness monitor is used as the pollutant concentration measurement monitor 15 or 17. Switching of each valve 11, 12, 13, 14, 18, 19 is automatically performed by a signal from the control unit 16 based on the TOC measurement result.

  The contaminant concentration of the gas to be processed is measured by the crystal oscillator type film thickness monitor 15. When the contaminant concentration is low, the valves 11 and 14 are opened, the valves 12 and 13 are closed, and the photocatalyst unit 2 purifies the gas. Normally, the valve 18 on the outlet side of the purification apparatus 10 'is opened and the valve 19 in the circulation path is closed. When the contaminant concentration is at a medium level, the valve 11 is closed, the valve 12 is opened, and the adsorbent filter unit 3 purifies the gas. When the contaminant concentration is high, the valves 11 and 13 are opened, the valves 12 and 14 are closed, and the gas is purified by both the photocatalyst unit 2 and the adsorbent filter unit 3.

  The contaminant concentration of the purified gas is monitored by the crystal oscillator type film thickness monitor 17. When the gas is purified only by the photocatalyst unit 2 and a contaminant is detected by the monitor 17, the valve 13 is opened and the valve 14 is closed, and the gas is purified by both the photocatalyst unit 2 and the adsorbent filter unit 3. Thus, the operation of the purification device 10 ′ is switched. When the gas is purified only by the adsorbent filter unit 3 and contaminants are detected, the valves 11 and 13 are opened, the valves 12 and 14 are closed, and the photocatalyst unit 2 and the adsorbent filter unit 3 are both closed. Switch operation to purify gas. When the gas is purified by both the photocatalyst unit 2 and the adsorbent filter unit 3 and a contaminant is detected, the valve 18 is closed, the valve 19 is opened, the gas is circulated, and purification is performed again.

The second example removes NO _x , SO _x , and ozone as pollutants in the gas to be treated. As the measurement monitors 15 and 17, a monitor for measuring NO _x , SO _x or ozone to be removed is used. If there are two or more contaminants to be removed, a measurement monitor for each contaminant is prepared.

  The measurement monitor 15 measures the contaminant concentration of the gas to be processed. When the contaminant concentration is high, the valve 11 is closed, the valve 12 is opened, and the adsorbent filter unit 3 purifies the gas. When the contaminant concentration is low, the valves 11 and 14 are opened, the valves 12 and 13 are closed, and the photocatalyst unit 2 purifies the gas. Normally, the valve 18 on the outlet side of the purification device 10 ′ is opened and the valve 19 is closed.

  The contaminant concentration of the purified gas is monitored by the measurement monitor 17. When the gas is purified only by the photocatalyst unit 2 and contaminants are detected by the measurement monitor 17, the valve 13 is opened and the valve 14 is closed, and the gas is purified by both the photocatalyst unit 2 and the adsorbent filter unit 3. Thus, the operation of the purification device 10 ′ is switched. When the gas is purified only by the adsorbent filter unit 3 and contaminants are detected, the valves 11 and 13 are opened, the valves 12 and 14 are closed, and the photocatalyst unit 2 and the adsorbent filter unit 3 are both closed. Switch operation to purify gas. When the gas is purified by both the photocatalyst unit 2 and the adsorbent filter unit 3 and contaminants are detected, the valve 18 is closed, the valve 19 is opened, the gas is circulated, and the purification process is performed again.

  The third example purifies the gas by removing ammonia. As the measurement monitors 15 and 17, an ammonia measurement monitor is used.

  The ammonia concentration of the gas to be processed is measured by the measurement monitor 15. When the ammonia concentration is high, the valves 11 and 13 are opened, the valves 12 and 14 are closed, and the gas is purified by both the photocatalyst unit 2 and the adsorbent filter unit 3. When the ammonia concentration is low, the valves 11 and 14 are opened and the valves 12 and 13 are closed and the gas is purified by the photocatalytic unit 2, or the valves 11 and 14 are closed and the valve 12 is opened and the adsorbent filter unit 3 is used. Purify. Normally, the valve 18 on the outlet side of the purification device 10 ′ is opened and the valve 19 is closed.

  The ammonia concentration of the purified gas is monitored by the measurement monitor 17. When ammonia is detected, the valve 18 is closed, the valve 19 is opened, the gas is circulated, and the gas is purified again. If purification is performed only with either the photocatalyst unit 2 or the adsorbent filter unit 3, the gas may be circulated, or the valve may be switched so that the unit that has been stopped is also operated. Alternatively, the unit that circulated and stopped the gas may be operated.

  FIG. 7 shows an example in which the valves 11, 12, 13, 14, 18, 19 of the fluid purification device 10 'described with reference to FIG. 6 are manually switched. In the fluid purification apparatus 10 ″ in this figure, a TENAX tube, which is a gas adsorption tube, is used for the measurement monitors 15 and 17. The adsorbed organic gas is desorbed from the TENAX tube and qualitatively and quantitatively analyzed by a gas chromatograph. Based on the results, manually operate each valve.

  As a result of analysis, when the organic gas having a small molecular weight is large, the valves 11 and 14 are opened, the valves 12 and 13 are closed, and the gas is purified only by the photocatalyst unit 2. When the organic gas having a large molecular weight is large, the valve 11 is closed, the valve 12 is opened, and the gas is purified only by the adsorbent filter unit 3. Normally, the valve 18 on the outlet side of the purification device 10 ″ is opened and the valve 19 in the circulation path is closed.

  A measurement monitor 17 monitors the organic gas concentration of the purified gas. When the organic gas is detected, the valves 11 and 13 are opened, the valves 12 and 14 are closed, and the gas is purified by both the photocatalyst unit 2 and the adsorbent filter unit 3. When the gas is purified by both the photocatalyst unit 2 and the adsorbent filter unit 3 and the organic gas having a low molecular weight is detected by the measurement monitor 17, the photocatalyst reaches the end of its life and the organic gas having a high molecular weight is detected. When the adsorbent filter is considered to have reached the end of its life, replace the one that has reached the end of its life. During this replacement, the valve 18 is closed, the valve 19 is opened, and the valves 11 to 14 are switched so that the gas is circulated through the normal (not replaced) photocatalyst unit 2 or the adsorbent filter 3.

  In the fluid purification devices 10, 10 ′, 10 ″ of FIGS. 5 to 7 that operate by switching the flow path of the gas to be treated, the dust removal filter unit 9 is disposed on the downstream side of the adsorption filter unit 3. It is not necessary to be located downstream of the adsorbent filter unit 3. For example, a dust removal filter having the same function is provided in the gas flow path before branching by the valves 11 and 12 for switching the flow path of the gas to be processed. 5-7, this dust removal filter may be used in place of the dust removal filter 9 in FIGS.5 to 7. Similarly, the fluid purification devices 10, 10 ′, 10 ″ of FIGS. The unit 8 is disposed between the adsorption filter unit 3 and the dust filter 9, but the position of the unit 8 is not limited to this, and for example, for switching the flow path of the gas to be processed. It is also possible to place the treated gas flow path before branching in lube 11,12.

  As already described, in the fluid purification device of the present invention, a photocatalytic unit having a small molecular weight and excellent in decomposing and removing low-boiling organic substances is arranged in the first stage to adsorb and remove high-boiling organic substances having a large molecular weight. An excellent adsorbent filter is placed in the second stage. As described with reference to FIGS. 5 to 7, in the fluid purification apparatus of the present invention, the fluid can be purified by using either unit or both units according to the type of contaminant in the fluid to be treated. However, regardless of the type of contaminant in the fluid to be treated, first, the gas to be treated may be introduced exclusively into the adsorbent filter unit that can adsorb and remove organic substances having a low molecular weight and a low boiling point. As purification proceeds and the adsorbent filter approaches saturation, low molecular weight organic matter begins to pass through the adsorbent filter and begins to be detected by a measurement monitor provided on the outlet side of the purification device. At this time, the flow path of the fluid to be treated is changed to be introduced from the photocatalyst unit, and the gas obtained by decomposing and removing the low molecular weight organic substance can be supplied to the adsorbent filter unit. Since the organic substance having a large molecular weight is supplied to the adsorbent filter unit in this way, it is possible to further continue the purification of the gas in the adsorbent filter approaching saturation.

  Alternatively, it is possible to always purify the fluid to be treated in the order of the photocatalyst unit and the adsorbent filter unit without changing the flow path of the fluid to be treated. Also in this case, since the gas from which the low molecular weight organic substances are decomposed and removed by the photocatalyst unit is supplied to the adsorbent filter unit, the maximum capacity of the adsorbent filter can be effectively used.

  As shown in FIG. 8, a constant temperature / humidity unit 22 using a chiller or the like can be added to the fluid purification apparatus of the present invention. The fluid purification device 21 shown in this figure includes the fluid purification devices 10, 10 ′, 10 ″ described with reference to FIGS. 5 to 7 except that the constant temperature / humidity unit 22 is included in front of the photocatalytic unit 2. The same reference numerals shown in Fig. 8 as used in Fig. 5-7 denote the same units as shown in Fig. 8. The device of Fig. 8, of course, It is possible to include devices (valves, measurement monitors, control units) which are shown in Fig. 5 to 7 but not shown in this figure, that the units can be arranged separately, and the position of the fluid transfer means 8 is changed. This is also possible as in the case of the purification devices 10, 10 ′, 10 ″ described above.

  By using the constant temperature / humidity unit 22, it is possible to supply gas under conditions optimal for purifying the gas in the subsequent photocatalyst unit 2 and adsorbent filter unit 3.

  Further, the fluid purification apparatus having the constant temperature / humidity unit 22 shown in FIG. 8 is also installed in a transport cart that requires a local clean storage unit for transporting wafers, etc. It can be used in place of a general transfer means such as a wafer.

  In FIG. 9, the example which used the fluid purification apparatus 31 of this invention for the environmental control in the clean booth 30 is shown. This fluid purification device 31 can also be configured in the same manner as the fluid purification devices 10, 10 ′, 10 ″ described with reference to FIGS. 5 to 7, and the reference numerals shown in FIG. 9 are used in FIGS. 8 are the same components as those shown in Fig. 8. The apparatus of Fig. 8 is also the components (valves, controls) shown in Figs. The unit can be arranged separately, and the position of the fluid transfer means 8 can be changed as in the case of the purifiers 10, 10 ′, 10 ″.

  Purified air that has been treated by the purifier 31 by introducing outside air is supplied to the clean booth 30. In order to increase the purification efficiency of the air in the clean booth 30, for example, 90% of the amount of gas processed by the purification device 31 is taken out from the clean booth 30 by the circulation passage 33 and together with the outside air introduced into the purification device 31. It may be. By this circulation, the purification efficiency of the purification device 31 can be increased (assuming that the same air as the clean air supplied from the purification device 31 to the clean booth 30 circulates, the circulation amount is 90% of the processing gas amount of the purification device 31). If it is%, the purification efficiency of the purification device 31 is improved 10 times).

  Furthermore, a constant temperature / humidity unit as described with reference to FIG.

  In FIG. 10, the example which used the fluid purification apparatus 41 of this invention for the environmental control of the opening part 40 of the SMIF-box 42 is shown. This fluid purification device 41 can also be configured in the same manner as the fluid purification devices 10, 10 ′, 10 ″ described with reference to FIGS. 5 to 7, and the reference numerals shown in FIG. 10 are used in FIGS. 10 are the same as those shown in Fig. 10. The apparatus of Fig. 10 is also the components (valves, controls) shown in Figs. The unit can be arranged separately, and the position of the fluid transfer means 8 can be changed as in the case of the purifiers 10, 10 ′, 10 ″.

  The opening 40 of the SMIF-box 42 is a part for automatically taking in and out the wafer 48 and the like in the device manufacturing process from the SMIF-box 42, and its environmental purification is required only when the SMIF-box 42 is opened and closed. When this is necessary, the purified air from the purification device 41 is supplied to the SMIF-box opening 40, and when supply is unnecessary, the entire amount is returned to the purification device 41 by the circulation flow path 43 and circulated. This switching can be performed by a valve (not shown).

The present invention is as described above. The features of the present invention will be described as follows together with various aspects.
(Appendix 1) An apparatus for removing contaminants from a fluid to be treated and purifying it, a photocatalyst capable of decomposing contaminants in the fluid to be treated, and a photocatalytic unit having an excitation light source for exciting the photocatalyst An adsorbent filter unit capable of adsorbing contaminants in the fluid to be treated, a photocatalytic unit disposed upstream of the adsorbent filter unit with respect to the flow direction of the fluid to be treated, and A fluid purification device comprising a dust removal filter unit disposed on the downstream side.
(Supplementary note 2) The fluid purification device according to supplementary note 1, further comprising switching means for selectively introducing the fluid to be treated into the photocatalyst unit or the adsorbent unit.
(Appendix 3) An apparatus for removing a contaminant from a fluid to be treated and purifying it, a photocatalyst capable of decomposing the contaminant in the fluid to be treated, and a photocatalytic unit having an excitation light source for exciting the photocatalyst An adsorbent filter unit capable of adsorbing contaminants in the fluid to be treated, a photocatalytic unit disposed upstream of the adsorbent filter unit in the flow direction of the fluid to be treated, and further, the fluid to be treated is a photocatalyst A fluid purification apparatus comprising switching means for selectively introducing into a unit or adsorbent unit.
(Additional remark 4) When the said to-be-processed fluid contains the contaminant suitable for the removal by the photocatalytic action in the said photocatalyst unit, the said to-be-processed fluid is introduce | transduced into the said photocatalyst unit, and the said to-be-processed fluid is the said adsorbent unit. The fluid purification device according to appendix 2 or 3, wherein when a contaminant suitable for removal by adsorption is included, the fluid to be treated is introduced into the adsorbent filter unit.
(Supplementary note 5) The fluid purification device according to supplementary note 4, wherein when the fluid to be treated contains a contaminant suitable for removal by photocatalytic action in the photocatalytic unit, the gas treated by the photocatalytic unit is bypassed by the adsorbent unit. .
(Appendix 6) When the concentration of the contaminant in the fluid to be treated is low, it is selectively purified by the photocatalytic unit, and when the concentration of the contaminant in the fluid to be treated is at a medium level, it is selectively purified The fluid purification device according to appendix 2 or 3, wherein the fluid purifier is purified by the adsorbent filter unit and purified by both the photocatalyst unit and the adsorbent filter unit when the concentration of the contaminant in the fluid to be treated is high. .
(Supplementary note 7) When the contaminant is detected in the purified fluid, when the fluid to be treated is selectively purified by the photocatalyst unit, the fluid to be treated is also purified by the adsorbent filter unit. The operation of the fluid purification device is switched, and when the fluid to be treated is selectively purified by the adsorbent filter unit, the operation of the fluid purification device is switched to purify the gas to be treated by the photocatalytic unit. The fluid purification device according to appendix 6, wherein when the fluid to be treated is purified by both the photocatalyst unit and the adsorbent filter unit, the fluid is circulated and purified again by the fluid purification device.
(Supplementary Note 8) When there is only one type of contaminant to be removed by the fluid purification device and the concentration of the contaminant in the fluid to be treated is high, both the photocatalytic unit and the adsorbent filter unit The fluid purification device according to appendix 2 or 3, wherein the treatment fluid is purified, and when the concentration of the contaminant is low, the treatment fluid is purified by either the photocatalyst unit or the adsorbent filter unit.
(Supplementary note 9) In the case where purification is performed by both the photocatalyst unit and the adsorbent filter unit, when the contaminant is detected in the purified fluid to be treated, the fluid to be treated is circulated. The fluid purification apparatus according to appendix 8.
(Supplementary Note 10) In the case where purification is performed by either the photocatalyst unit or the adsorbent filter unit, when the contaminant is detected in the fluid to be treated, the fluid to be treated is The fluid according to appendix 8, wherein the unit that has been circulated or not purified is also used for purification, or the unit that has been circulated and not purified is also used for purification. Purification equipment.
(Supplementary note 11) The fluid purification device according to Supplementary note 2 or 3, wherein the switching means is an automatic means.
(Supplementary note 12) The fluid purification device according to Supplementary note 2 or 3, wherein the switching means is manual means.
(Additional remark 13) The fluid purification means of Additional remark 2 which further contains the fluid transfer means for transferring the said to-be-processed fluid.
(Supplementary note 14) The fluid purification device according to supplementary note 13, wherein the fluid transfer means is located between the adsorbent filter unit and the dust filter unit.
(Supplementary note 15) The fluid purification means according to supplementary note 3, further comprising a fluid transfer means for transferring the fluid to be processed.
(Supplementary Note 16) The supplementary note 15 further includes a dust removal filter unit disposed on the downstream side of the adsorbent filter unit, and the fluid transfer means is located between the adsorbent filter unit and the dust removal filter unit. The fluid purification apparatus as described.

DESCRIPTION OF SYMBOLS 1, 10, 10 ', 10 ", 21, 31, 41 Fluid purification apparatus 2 Photocatalyst unit 3 Adsorbent filter unit 8 Fluid transfer means unit 9 Dust removal filter unit 11, 12, 13, 14, 18, 19 Valve 15, 17 Contaminant concentration measurement monitor 16 Control unit

Claims (10)

  An apparatus for removing contaminants from a fluid to be treated and purifying the same, a photocatalyst capable of decomposing the contaminants in the fluid to be treated, a photocatalyst unit having an excitation light source for exciting the photocatalyst, and a fluid to be treated An adsorbent filter unit capable of adsorbing contaminants therein, the photocatalyst unit is disposed upstream of the adsorbent filter unit with respect to the flow direction of the fluid to be treated, and further disposed downstream of the adsorbent filter unit. A fluid purification device comprising a dust removal filter unit.   The fluid purification device according to claim 1, further comprising switching means for selectively introducing the fluid to be treated into the photocatalyst unit or the adsorbent unit.   An apparatus for removing contaminants from a fluid to be treated and purifying the same, a photocatalyst capable of decomposing the contaminants in the fluid to be treated, a photocatalyst unit having an excitation light source for exciting the photocatalyst, and a fluid to be treated An adsorbent filter unit capable of adsorbing contaminants therein, the photocatalyst unit is disposed upstream of the adsorbent filter unit with respect to the flow direction of the fluid to be treated, and the fluid to be treated is a photocatalytic unit or an adsorbent A fluid purification device comprising switching means for selectively introducing into a unit.   When the fluid to be treated contains a contaminant suitable for removal by photocatalytic action at the photocatalytic unit, the fluid to be treated is introduced into the photocatalytic unit, and the fluid to be treated is removed by adsorption at the adsorbent unit. The fluid purification apparatus according to claim 2 or 3, wherein when a suitable contaminant is contained, the fluid to be treated is introduced into the adsorbent filter unit.   The fluid purification device according to claim 4, wherein when the fluid to be treated contains a contaminant suitable for removal by photocatalytic action in the photocatalytic unit, the gas treated by the photocatalytic unit is bypassed by the adsorbent unit.   When the concentration of contaminants in the fluid to be treated is low, it is selectively purified by the photocatalytic unit, and when the concentration of contaminants in the fluid to be treated is at a medium level, it is selectively purified by the adsorbent. The fluid purification device according to claim 2 or 3, wherein the fluid purification device purifies by a filter unit and purifies it by both the photocatalyst unit and the adsorbent filter unit when the concentration of contaminants in the treated fluid is high.   When the pollutant is detected in the purified fluid, when the fluid to be treated is selectively purified by the photocatalyst unit, the fluid purification is performed so that the fluid to be treated is also purified by the adsorbent filter unit. When the operation of the apparatus is switched and the fluid to be treated is selectively purified by the adsorbent filter unit, the operation of the fluid purification apparatus is switched so that the gas to be treated is also purified by the photocatalytic unit, and the photocatalytic unit The fluid purification device according to claim 6, wherein when the fluid to be treated is purified by both the adsorbent filter unit and the fluid purification device, the fluid is circulated and purified again by the fluid purification device.   When there is only one kind of contaminant to be removed by the fluid purification device and the concentration of the contaminant in the fluid to be treated is high, the fluid to be treated is purified by both the photocatalyst unit and the adsorbent filter unit. The fluid purification device according to claim 2 or 3, wherein when the concentration of the contaminant is low, the fluid to be treated is purified by one of the photocatalyst unit and the adsorbent filter unit.   9. When purification is performed by both the photocatalyst unit and the adsorbent filter unit, when the contaminant is detected in the treated fluid subjected to the purification, the fluid to be treated is circulated. The fluid purification apparatus as described.   In the case where purification is performed in either the photocatalyst unit or the adsorbent filter unit, when the contaminant is detected in the treated fluid subjected to the purification, the treated fluid is circulated, The fluid purification device according to claim 8, wherein the unit that has not been purified is also used for purification, or the unit that has been circulated and not purified is also used for purification.

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