JP2009138975A - Cleaning method of clean room exhaust - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To continuously circulate and supply the exhaust from a clean room to the clean room and the like for a long period by taking the exhaust from the clean room and the like used in a process of manufacturing an electronic apparatus, a precision apparatus and the like, and performing the cleaning to remove molecular contaminants and particulate contaminants. <P>SOLUTION: In this cleaning method of the clean room exhaust, the process air is allowed to pass through a temperature/humidity conditioner, and then pass through a batch-wise temperature swing adsorbing device using the air taken from the inside or outside of a room as regenerated air, or allowed to pass through the batch-wide temperature swing adsorbing device using the air taken from the inside or outside of the room as the regenerated air, and then pass through the temperature/humidity control device, in cleaning the exhaust from a clean working space such as the temperature/humidity-conditioned clean room and the like, as the process air, and circulating and supplying the same to the clean working space. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention takes in exhaust from a clean room, a clean chamber or a mini-environment used in a process of manufacturing electronic equipment, electronic parts, precision equipment, precision parts, etc. as processing air, and basic molecules in the processing air After cleaning and controlling the temperature to remove particulate contaminants, organic molecular contaminants and / or acidic molecular contaminants and particulate contaminants, this is applied to the clean room, clean chamber or mini-environment for a long time. The present invention relates to a method that enables continuous circulation supply over a period of time.

  Conventionally, electronic devices and their components, precision devices and their components, etc. have been processed and manufactured in a clean room maintained at a high degree of cleanliness. In a general clean room, cleaning is performed to remove particulate pollutants such as dust and mist from the air taken from outside the system, and the temperature is controlled and continuously supplied to the clean room. The air-conditioning system of the system which keeps the supply amount substantially the same amount as the total exhaust amount from a clean room, a clean chamber, or a mini-environment is used.

  However, the air discharged outside the system is temperature-controlled using energy as described above. From the viewpoint of energy saving, the amount of air discharged outside the system is reduced as much as possible, It is preferable to clean the air so that it can be circulated. In addition, when a processing operation is performed on a workpiece in a clean room using a chemical, molecular contaminants are generated along with the processing operation. Therefore, in recent years, when air in a clean room is circulated. In addition, an air cleaning device has been developed that can suitably remove not only particulate contaminants but also molecular contaminants.

(Conventional technology)
Among them, as a particulate pollutant removal device, a high performance filter is installed in various places in a pipeline for circulating and supplying air in a clean room, and removal according to the cleanliness class is performed. That is, FIG. 5 is an explanatory view of a cleaning device according to the prior art. As a high performance filter, a high performance filter (3) 61 and / or an upstream side of the processing air inlet 1 to the temperature and humidity control device 60 are used. A fan filter unit (FFU) 110 that is installed on the downstream side (not shown) or integrated with the filter fan (1) 114 at the clean temperature-controlled humidity air outlet 105 in the clean room 100 according to the prior art. It is arranged as a high performance filter (4) 115 inside. 5 includes a high-performance filter (3) 61, a conventional cooling / dehumidifying device 62, a conventional warming device 63, and a conventional humidifying device 64. The purified temperature-controlled and humidity-controlled air is boosted by the purified temperature-controlled and humidity-controlled air blower (3) 101 and flows into the purified temperature-controlled and humidity-controlled air supply port 2.

  Molecular contaminants are generated when chemicals are handled in processing operations in a clean room. In many cases, basic substances such as trimethylamine (TMA), triethylamine (TEA), N-methylpyrrolidone (NMP), and Organic amines; and organic substances such as cinna, toluene, xylene, ethylene glycol monobutyl ether (EGMBE), propylene glycol monomethyl ether acetate (PGMEA), methyl isobutyl ketone (MIBK), ethyl lactate, cyclohexanone .

Other molecular pollutants include basic ammonia derived from the ambient air, human body and chemicals handled, acidic NOx, SOx, Cl ⁻ present in the ambient air, and a very wide variety of organic substances present in the ambient air. It is a sex substance.

Moreover, 60 to 70 kinds of organic molecular pollutants including amines existing in the ambient air are detected with only main ones, the molecular weight is in the range of 50 to 350, and the concentration is 5 μg / m ³ at the maximum. many in the range of 0.2~0.01μg / m ^3, the total amount is about 50 [mu] g / m ³ in hexadecane conversion.

  On the other hand, chemical filters are widely used as molecular contaminant removal devices, and are disposed at a plurality of locations in a pipeline that circulates and supplies air in a clean room, as with high-performance filters. That is, in FIG. 5, in the chemical filter unit 80 installed on the upstream side of the conventional temperature and humidity control device 60, usually three types of chemical filters (A1) 81, chemical filters (B1) 82, and chemical filters ( C1) 83 is incorporated.

  In the fan filter unit (FFU) 110, a chemical filter (A2) 111, a chemical filter (B2) 112, and a chemical filter (C2) 113 are incorporated. Here, the chemical filter (A) collects acidic molecular contaminants, the chemical filter (B) collects basic molecular contaminants, and the chemical filter (C) collects organic molecular contaminants and removes them by adsorption.

  Among these, the chemical filter (B) is a cloth filter material impregnated with an acidic agent, a fiber filter material added with a cation exchange group, or a cloth filter material sewed into a bag shape with pleats. And what filled the cation exchange resin in the bag is used.

  Therefore, the principle of collection / removal in the chemical filter (B) is to cause neutralization reaction of acid and base on the filter material to convert it into a non-volatile neutralized product. Therefore, basic contaminants exceeding the chemical equivalent of the basic substance that reacts with the amount of acidic substances impregnated in the filter material cannot be collected and removed. . For this reason, the chemical filter (B) that has reached the end of its life inevitably undergoes a large-scale work, which will be described later, to replace it with a new one.

  On the other hand, the chemical filter (C) that collects and removes organic substances is made by sewing a cloth-like filter material with pleats and sewing it into a bag shape and filling the bag with granular activated carbon, or activated carbon fiber. A filter material is used.

  Therefore, the principle of collection / removal in the chemical filter (C) is to physically adsorb organic substances with high selectivity, so that the amount of organic pollutants exceeding the saturated adsorption amount of the packed activated carbon is collected / removed. Since this becomes impossible, there is a problem that a lifetime also exists. Of the amines, strong basic amines are collected and removed by the chemical filter (B), and weak basic amines are collected and removed by the chemical filter (C).

  That is, as in the case of the above-described chemical filter (B), the chemical filter (C) that has reached the end of its life is inevitable to replace it with a new one.

  Furthermore, the chemical filter (A) for collecting / removing acidic substances is obtained by impregnating a cloth-like filter material with a basic agent, a fiber filter material with an anion exchange group added, or a cloth-like filter material. A pleated sewed bag is used, and the bag is filled with an anion exchange resin.

  Therefore, the principle of collection / removal in the chemical filter (A) is to cause a neutralization reaction between the base and the acid on the filter material to convert it into a non-volatile neutralized product. Therefore, the amount of acidic pollutants exceeding the chemical equivalent of the acidic substances that react with the amount of basic substances impregnated in the filter material cannot be collected and removed, which inevitably has a problem of having a lifetime. .

  As described above, as in the case of the above-described chemical filters (B) and (C), the chemical filter (A) that has reached the end of its life is inevitable to replace it with a new one.

  As described above, in general, chemical filters (A), (B), and (C) all have a lifetime and become industrial waste due to replacement work, and the clean work space in which they were attached during replacement work. The manufacturing process at will stop operations. In both the recent semiconductor manufacturing and liquid crystal display manufacturing fields, the size of the substrate is increasing, which increases the amount of industrial waste and increases the frequency of replacement.

  Furthermore, at the time of replacement, the clean work space, the clean air pipeline, and related equipment are exposed to the atmosphere outside the process equipment. Since the atmosphere in the clean air to be supplied is 0.1 ppb or less and the organic matter is 3.2 ppb or less, the atmosphere is clearly an air containing ammonia exceeding 0.1 ppb and organic matter exceeding 3.2 ppb. Before the replacement, the clean work space, the clean air conduit, the related equipment to which it is connected, and the inside of the equipment are surely contaminated. In particular, ammonia and water molecules tend to adsorb and adhere to the metal surface.

  Therefore, even if the replacement work is completed, a long-time cleanup work is required to restore the clean work space, the clean air conduit, and related equipment to the clean air atmosphere. Loss due to shutdown during this period has caused enormous problems.

  In addition, as described above, when it is exposed to indoor air containing ammonia that is always present at 3 to 5 ppb, for example, when adsorbing and adhering to the metal surface, the ammonia adhering to the metal surface is little by little due to the flow of clean air after restoration. Detach and mix in clean air stream. For example, if the ammonia concentration is 0.2 ppb due to this desorption, it is considered that the probability of contaminating the glass substrate in the clean work space is doubled. Moreover, when water molecules in clean air condense on the metal surface or the like by molecular motion, the ammonia concentration in clean air becomes 0.2 ppb or more due to the rectification effect that ammonia molecules take away the heat of condensation and vaporize. . That is, it is extremely difficult to make ammonia having a low molecular weight and a low boiling point 0.1 ppb or less from the temperature-controlled and humidity-controlled air.

  Furthermore, as described above, in clean room exhaust, amines that are basic and organic with ammonia are used as molecular pollutants, and many kinds of organic molecular pollutants and acidic molecular pollutants. Are mixed. When these molecular contaminants are collected and removed by the chemical filters (A), (B), and (C), ammonia and TMA are collected and removed by the chemical filter (B) with high selectivity. However, TEA and NMP have a low rate of collection / removal by the chemical filter (B) and are mainly collected / removed by physical adsorption by the chemical filter (C). However, since the adsorption capacity of the chemical filter (C) is generally small, other organic molecular pollutants having a higher molecular weight than TEA and NMP are preferentially adsorbed, so that the time is shorter than expected. The collection / removal rate of TEA and NMP decreases. As a result, the chemical filter (C) needs to be replaced with a new one in a short time.

In addition, as described above, the exhaust of the clean work space introduced, that is, in the processing air, the basic ammonia and the molecular contaminants of amines that are basic and organic, and various organic molecular contaminants with a molecular weight, and NOx, SOx, Cl ^- acidic molecular contaminants, such as are mixed. In addition, the state of occurrence of each molecular pollutant occurs at the moment of using the drug containing the component or at the moment of using a drug that generates the molecular pollutant by a chemical reaction. The concentration of the molecular pollutant rapidly changes in a pulsating manner with a fluctuation range of several ppm to 1 ppb.

Although the fluctuation state of the concentration of such molecular contaminants is somewhat leveled at the processing air inlet, the chemical filter (A1) 81 and the chemical filter (B1) 82 shown in FIG. When flowing into the chemical filter (C1) 83, when there is a sufficient margin in the adsorption capacity of each chemical filter, the chemically adsorbed NOx, SOx, Cl ⁻ are collected and removed by the chemical filter (A1) 81, Ammonia and TMA are collected and removed by chemical filter (B1) 82, and TEA, NMP, cinna, EGMBE, PGMEA, MIBK, ethyl lactate, cyclohexanone, etc. that are physically adsorbed are collected by chemical filter (C1) 83. Collected and removed.

  However, for example, when NMP (molecular weight: 99.1) and PGMEA (molecular weight: 132.2) are used in a processing operation in a clean work space, the chemical filter ( In C1) 83, these molecular contaminants are collected and removed. However, when the margin of the adsorption capacity of the chemical filter (C1) 83 becomes small, a processing operation using PGMEA is performed, and the chemical filter (C1) 83 has a pulsating shape in which the maximum value is on the order of ppm. When it flows in, a phenomenon occurs in which NMP is expelled from the chemical filter (C1) 83 by PGMEA. At the same time, a pollutant having a molecular weight smaller than that of NMP derived from the atmosphere adsorbed on the chemical filter (C1) 83 is driven out by PGMEA and leaks downstream. The present inventors have found that the above phenomenon occurs.

  At a point in time when the adsorption capacity of the chemical filter (C2) 113 provided at the downstream purified temperature and humidity control air outlet 105 (FIG. 5) is sufficient, the molecular weight is larger than NMP leaked from the chemical filter (C1) 83 and NMP. Small molecular contaminants are collected and removed by the chemical filter (C2) 113. However, at the time when the capacity of the adsorption capacity becomes small, a contaminant having a molecular weight smaller than that is expelled by NMP in the same manner as described above, and a phenomenon of polluting the clean work space of the prior art occurs.

  As described above, the chemical filter has a limited adsorption capacity, and needs to be replaced periodically or irregularly when the above-described phenomenon occurs. In exchange, a large-scale replacement work accompanied by a stop of the processing work in the clean room occurs. In addition, since it is difficult to regenerate the adsorption capacity of the used chemical filter, it must eventually be discarded. That is, it becomes industrial waste. However, from the viewpoint of environmental protection, there is a strong demand from society for further reduction of industrial waste, so we have developed an air cleaning device that can be reused repeatedly from disposable types such as chemical filters. There is a strong demand to do.

  Therefore, recently, an air purifying apparatus or a high-purity air preparation apparatus that can perform adsorption and regeneration at the same time using a renewable adsorbent without using a chemical filter and can be used semipermanently has been proposed. (See Patent Document 1).

Japanese Patent Laid-Open No. 2001-141274 Japanese Patent No. 3320730 Japanese Patent No. 3078697 2005 Semiconductor Manufacturing Equipment Technology Roadmap Report (Published by Japan Semiconductor Manufacturing Equipment Association)

  This air cleaning device is a honeycomb laminate rotor that is formed such that a honeycomb laminate comprising zeolite as a main component is formed on a cylinder and air passes in the axial direction thereof, and the rotor is rotated about the axis. The driving means is provided. The space in which the honeycomb laminated body rotor rotates is divided into an adsorption part, a regeneration part, and a cooling part around the axis. That is, the adsorption unit, the regeneration unit, and the cooling unit are sequentially moved, and this is repeated continuously.

  In this air purification apparatus, the processing air (air containing pollutants) is purified through the adsorption portion of the honeycomb-shaped laminate and supplied to the clean room, and at the same time, the heated air is used as regenerated air as the regeneration portion of the honeycomb-shaped laminate. The molecular pollutant adsorbed by the adsorbing part is separated into heated air and discharged.

  Here, the processing air operates a blower to introduce clean room air into the apparatus. The introduced air (process air) flows down in the process air duct, is sent to the honeycomb-shaped laminated body rotor, is cleaned, and is circulated and supplied to the clean room. In this air cleaning device, a part of the outside air is taken in from the outside air supply means and mixed into the processing air.

  That is, the molecular contaminants are adsorbed and removed by the adsorbing portion while the processing air mixed with a part of the outside air passes from one direction side to the other side in the axial direction of the honeycomb laminated rotor. The treated air cleaned by the adsorbent passes through a dust filter to remove particulate contaminants and is circulated and supplied to the clean room.

By the way, as mentioned above, there are already many kinds of organic molecular pollutants, basic molecular pollutants such as ammonia and amines, and acidic molecular pollutants such as NOx and SOx. is doing. In the clean work space, various organic substances and basic substances are handled. Recently, basic substances such as triethylamine (TEA), trimethylamine (TMA) and N-methylpyrrolidone (NMP) are used. Organic materials are also often handled. They become molecular contaminants and enter the clean air. Thus, the process air is not limited to the organic, basic molecular contaminants typified by ammonia, Cl ^-, SOx, acidic molecular contaminants, such as NOx, a basic and organic molecules like There will be pollutants.

  Therefore, in order to efficiently adsorb and remove these molecular contaminants, it is not only necessary to change the ratio of weak hydrophobicity and strong hydrophobicity of zeolite, which is an adsorption member supported on the honeycomb-shaped laminate, It describes that when there are molecular contaminants that are difficult to adsorb and remove at the adsorbing portion of the honeycomb laminated rotor, an additional chemical filter is installed between the air cleaning device and the clean room. Yes. As described above, the air cleaning device described in Patent Document 1 is a device that uses an adsorption rotor and a chemical filter (chemical adsorption filter) as industrial waste in combination.

  On the other hand, by using adsorbents such as activated carbon, silica gel, molecular sieve, zeolite, etc., which are conventionally known as adsorbents for adsorbing and removing molecular pollutants by introducing clean room exhaust gas, non-methane hydrocarbons in exhaust gas are reduced to 0. A method and apparatus for preparing a clean gas that is adsorbed and removed to 2 ppm or less are disclosed (see Patent Document 2).

  The method for preparing clean gas from clean room exhaust gas shown in Patent Document 2 describes that it is effective for adsorption removal of non-methane hydrocarbon molecular contaminants. It is not clear that contaminants can be removed down to the ppb order. There is no mention of adsorbents applicable to the removal of basic molecular pollutants mixed in exhaust gas and the removal of acidic molecular pollutants, basic and organic molecular pollutants.

  In addition, as a method for preparing clean air to be circulated and supplied to a clean room containing equipment required for the manufacturing process of semiconductor wafers and glass substrates, a rotor type air cleaning device composed of an adsorbent added with zeolite or activated carbon is used. There has been disclosed a method for removing hydrocarbons of olefin, paraffin, aromatic and diolephine, which are organic molecular pollutants in the processing air, to 0.1 ppm or less (see Patent Document 3).

  Since the said patent document 3 is a thing of an adsorbent rotor type | mold, adsorption | suction and reproduction | regeneration can be repeated simultaneously in parallel. However, it is used for processing of basic molecular pollutants and acidic molecular pollutants mixed with organic molecular pollutants in the ambient air and clean work space. There is no mention of adsorbents, devices and methods that can be repeatedly adsorbed and regenerated that can be applied to the removal of basic molecular contaminants and basic and organic molecular contaminants that are mixed in. Furthermore, it is not clear that hydrocarbons can be removed up to several ppb.

In particular, the concentration of contaminants in dry high-purity air used in state-of-the-art semiconductor manufacturing is such that ammonia, which is a typical basic molecular contaminant, has a concentration of 0.1 ppb or less, that is, 0.1 μg. / M ³ or less, the organic molecular pollutant is 22 ppb or less in terms of hexadecane, that is, 22 μg / m ³ or less, and the typical acidic molecular pollutant SOx is 0.1 ppb or less in terms of SO ₄ , that is, 0.1 μg / m ³ or less is required.

  In other words, for the removal of ammonia, which is a typical basic molecular pollutant, an adsorbent with a high selectivity that can be further reduced from the concentration in the purified air described in Patent Document 1 is required. In addition, there is a cleaning method that can improve the removal rate more reliably and achieve 22 ppb or less in terms of hexadecane than the cleaning method described in Patent Document 3 for the removal of organic molecular contaminants. It is strongly requested.

  In addition, basic and acidic molecular pollutants that are naturally mixed with organic molecular pollutants in the ambient air are also used in processing operations to be mixed into clean air. It is desired to develop a cleaning method that can circulate and supply basic and organic molecular contaminants continuously and stably over a long period of time using an adsorbent that can be repeatedly regenerated.

(Batch temperature swing adsorption device)
Next, the process air (air containing the pollutant) is passed through a batch-type temperature swing adsorption device (hereinafter sometimes referred to as a batch-type TSA device) according to the prior art to adsorb and remove the pollutant, and purified air. The technical problem that arises in the process will be described with reference to the drawings.
FIG. 4 is a block diagram of a batch type TSA apparatus 120 according to the prior art. FIG. 4 shows the case where the adsorption mode is the (A) system, and thus the regeneration mode is the (B) system.

  Process air flows from the process air inlet 1 and flows down the high-performance filter (1) 11, and then passes from the branch / merging joint T1 to the adsorbent unit (A) 13A via the on-off valve V1 and the branch / merging joint T2. Inflow. The adsorbent unit (A) 13A adsorbs and removes basic molecular contaminants, organic molecular contaminants, and / or acidic molecular contaminants.

  That is, the processing air is cleaned while passing through the adsorbent unit (A) 13A, and flows into the clean air outlet 16 through the branch / merging joint T3, the on-off valve V2, and the branch / merging joint T4. At this time, the on-off valves V1 and V2 are open, but the on-off valves V4, V5, V6, and V3 are closed.

  On the other hand, the regeneration air takes indoor or outdoor air from the regeneration air intake 26 and flows it into the regeneration air cooling and heating unit 28. That is, the regeneration air passes through the regeneration air filter 21 and flows down the regeneration air blower 22, the regeneration air cooler 23, the regeneration air preheater 24, and the regeneration air heater 25. Subsequently, it flows into the adsorbent unit (B) 13B through the branch / merging joint T8, the on-off valve V7, and the branch / merging joint T5. During the heating time zone in the regeneration mode, the refrigerant of the heat transfer medium used for the regeneration air cooler 23 is not circulated, and the regeneration air heater 25 is energized.

  Therefore, since the adsorbent unit (B) 13B is heated by the regeneration air, it desorbs the basic molecular contaminants, organic molecular contaminants and / or acidic molecular contaminants adsorbed during the adsorption mode. The regeneration air that has flowed out of the adsorbent unit (B) 13B flows into the regeneration air preheater 24 via the branch / merging joint T6, the on-off valve V8, and the branch / merging joint T7. The regeneration air preheater 24 preheats the low temperature regeneration air with the excess heat of the high temperature regeneration air. The high-temperature regeneration air is discharged from the regeneration air outlet 27 as cooling air becomes exhaust air.

  Further, during the cooling time zone in the regeneration mode, the regeneration air cooler 23 is circulated through the refrigerant of the heat transfer medium, and the regeneration air heater 25 is not energized. Therefore, the adsorbent unit (B) 13B is cooled by the regeneration air and is brought close to the temperature of the processing air to prepare for switching the adsorption mode. When the regeneration mode is the (B) system, the on-off valves V7 and V8 are in an open state.

  Thus, in a conventional batch-type TSA apparatus having two adsorbent units, if the adsorption and regeneration modes are executed simultaneously to continuously supply clean air, treated air, regenerative air, clean air, It is necessary to prevent the exhaust air from being mixed with each other, and to connect each of the (A) system adsorbent unit (A) 13A and (B) system adsorbent unit (B) 13B to the duct through which the air flows. For this reason, the upstream side of the adsorbent unit includes two ducts through which the processing air or exhaust air flows and the processing air, and the branch / merging joint T1 that branches to the respective adsorbent units of the system (A) and the system (B), V1, V4, V5 and V8 for opening / closing the duct branch / junction joint T7 for connecting the exhaust air to the duct for guiding the exhaust air from the system (A) and the system (B) to the regeneration air discharge port 27 and on both sides thereof. Need to be placed.

  Further, on the downstream side of the adsorbent unit, there are two ducts through which clean air or regenerated air flows, and a duct connected to a duct leading to the clean air outlet 16 from the (A) system duct and (B) the system duct. Branch / joint joint T4, installed on both sides of the branch / joint joint T8 and each branch / joint joint that guides the regenerative air and sends it to the adsorbent units of (A) system and (B) system, and opens and closes the duct It is necessary to arrange the on-off valves V2, V3, V6 and V7 for this purpose.

  Furthermore, branch / merging joints T2, T6 are connected from the regeneration air duct to the (A) system duct so that the regeneration air flows from (A) the system duct to the exhaust air duct or (B) from the system duct to the exhaust air duct. Alternatively, branching / merging joints T3 and T5 are necessary so that the regeneration air flows from the regeneration air duct to the (B) system duct. Eventually, two systems on the upstream and downstream sides of the adsorbent unit (A) 13A and the adsorbent unit (B) 13B, a total of four ducts, a total of eight on-off valves, and a total of eight branch / merging joints is required.

This necessitates a “compulsion” of extremely complex and long ducts. Here, the duct used in the clean work space targeted by the present invention is not a small pipe having a diameter of about 50 mm. For example, a square cross section duct of 500 mm (when the processing air amount is 100 m ³ / min, the size of the square cross section duct is 500 mm in order to flow at a flow rate of about 8 m / s). If it is 30 m, an occupied space of 6.2 m ³ is required only with the duct. Similarly, when the amount of processing air is 20 m ³ / min, a flow rate of about 8 m / s is required, and when the amount of air is 30 m, an occupied space of 1.3 m ³ is required only with the duct.

  In other words, the space occupied by the duct through which the air under normal pressure flows is actually enormous, including the duct branch / merge joint, duct overlap, crossover, bending, expansion (reduction), open / close valve, heat insulation Since a space necessary for mounting the material is added, the occupied space as the whole apparatus becomes extremely large.

  This is the first reason that it is difficult to make a conventional batch-type TSA apparatus having two adsorbent units compact.

  When switching the adsorption mode from the (A) system to the (B) system and the regeneration mode from the (B) system to the (A) system, the open / close valves V1, V2, V7 and V8 in the open state are closed. The on-off valves V4, V5, V3 and V6 in the closed state are switched to the opened state. Conversely, when switching the adsorption mode from the (B) system to the (A) system and the regeneration mode from the (A) system to the (B) system, the on-off valves V1, V2, V7 and V8 are opened from the closed state to the open state. The on-off valves V4, V5, V3 and V6 are switched from the open state to the closed state.

  Further, switching between the adsorption mode and the regeneration mode simultaneously starts and stops the operation of the eight open / close valves having a small pressure loss and a large diameter without stopping the flow of the processing air and the clean air. In addition, the operation time must be as short as possible.

  However, it is extremely difficult to start all the eight on-off valves at the same time, stop the operation at the same time, and operate them in a short time. If there is a slight delay in any of the on-off valves, there is a big problem that the flow rate and pressure of clean air fluctuate.

  If the flow rate and pressure of the clean air fluctuate at the time of switching as described above, this is a major factor that significantly reduces the yield of processed products.

  Still another problem is that in the prior art batch-type TSA device 120 of FIG. 4, when switching between the adsorption mode and the regeneration mode, a duct between the eight branch / junction joints and the eight on-off valves is provided. Since the flow of the air stops when the on-off valve is closed, it becomes a stagnation point where it stays until the next valve is opened. In FIG. 4, a duct that becomes a stagnation portion is indicated by a broken line.

  For example, the duct between the on-off valve V4 and the branch / merging joint T6 becomes a stagnation place where exhaust air containing a high concentration of desorbed pollutants immediately after the start of regeneration stays, so that the pollutants in the clean air after switching There is a problem of affecting the concentration. Further, the duct between the branch / merging joint T1 and the on-off valve V4 also has a stagnation point where exhaust air containing high-concentrated desorbed pollutants immediately after the regeneration starts if there is a delay in the on-off operation of the on-off valve V4. Become.

  Furthermore, in the cooling time zone of the regeneration mode of FIG. 4, since air is taken in from indoors or outdoors, the regeneration air contains 3 to 5 ppb of ammonia. Therefore, the duct between the branch / merging joint T5 and the adsorbent unit 13B is contaminated by the ammonia in the regeneration air, and the ammonia concentration in the clean air after switching changes.

  As is clear from the above description, when a chemical filter is used as an air cleaning device, a serious replacement operation is required in which a new filter is replaced regularly or irregularly depending on circumstances. In addition, when performing the work, there is a problem that it is inevitably necessary to stop the processing work in the clean room, and there is also an environmental problem that industrial waste is generated. Furthermore, after the replacement work is completed, it is necessary to perform a cleanup work to restore the clean state, so that the machining work must be stopped. During this time, economic loss and energy waste problems occur simultaneously.

  On the other hand, if it is intended to maintain a certain amount of processing, there is a problem that a spare clean work space must be installed, and capital investment increases. In addition, the collection / removal rate of basic, organic, and acidic molecular contaminants has a large effect on the product yield and must be constantly monitored. Although it depends on the size of the clean work space, chemical filters are installed in many places, and management of individual chemical filters, securing of monitoring personnel, introduction and installation of monitoring devices are indispensable. This will inevitably increase the cost of processed products.

  As described above, when a chemical filter is used as an air cleaning device, the cost of the processed product is increased, and environmental problems and energy waste are induced. Therefore, it is inevitable to develop a method for modifying a method using a chemical filter, that is, a method not using a chemical filter.

  However, simply using a batch-type TSA apparatus according to the prior art requires an extremely complicated and long drawing duct and prevents the apparatus from being made compact, so enormous capital investment is inevitable. In addition, the difficulty of operating the four large-diameter open / close valves from open to closed, and the other four large-diameter open / close valves simultaneously from closed to open, and the resulting flow and pressure fluctuations are unavoidable. After the mode switching, a problem of mixing high-concentration molecular contaminants from the stagnation site into clean air, that is, a concentration fluctuation problem of molecular contaminants also occurs.

On the other hand, an air cleaning device using an adsorbent rotor that can be adsorbed and regenerated simultaneously using an adsorbent that can be regenerated without using the chemical filter proposed in Patent Document 1 and Patent Document 3, and can be used semipermanently. Has the following problems:
First, it is necessary to draw a long duct, and at the same time, since the cross section of the adsorbent rotor and the cross section of the duct are completely different, many joints having a complicated structure are required. Therefore, it is difficult to make a compact device. Second, it is impossible to prevent leakage of treated air, regenerated heated air, and regenerated cooling air from the sliding portion between the joint end surface and the adsorbent rotor end surface.
Third, the adsorbent rotor must be divided into three areas: adsorption, regeneration, and cooling. These areas include flow velocity or flow rate, temperature, pressure, flow direction, and pollutant quality (organic, basic). It is extremely difficult to prevent mixing of processing air, regeneration heating air, and regeneration cooling air having different concentrations. In other words, it is clearly difficult to clean the high-purity air described in Non-Patent Document 1 with the adsorption rotor.
Fourthly, the regenerative heating air and the regenerative cooling air flow continuously so that the energy consumption is large. Fifth, there is no mention regarding removal / cleaning of pollutants when ammonia that is surely present in the processing air and basic and organic TEA, TMA, and NMP coexist.

The present invention has been made in view of the above-mentioned facts, and incorporates exhaust from a clean work space such as a temperature-controlled and clean room, a clean chamber, and a mini-environment as process air, When cleaning exhaust containing basic molecular pollutants, organic molecular pollutants, basic and organic molecular pollutants and / or acidic molecular pollutants derived from the ambient air, the clean work space Non-Patent Document 1 describes air suitable for processing operations performed in the clean work space after cleaning with an adsorbent material without stopping the processing operation, and adjusting the temperature and humidity more precisely. the molecular contaminants as, ammonia 0.1ppb or less, organic molecular contaminants 22ppb or less hexadecane conversion, SOx (sO ₄ equivalent) 0 1ppb prepared in high purity air removal below, provides a continuous process stably circulate and supply a long period of time on the clean work space, it is intended to solve the aforementioned problems.

As a result of intensive studies to solve the above-described problems, the present inventors have mixed ammonia 50 ppb, PGMEA 500 ppb, and toluene 270 ppb into the ambient atmosphere, and mixed ammonia 50 ppb, NMP 290 ppb, and toluene 270 ppb into the ambient atmosphere. The first layer uses an adsorbent containing activated carbon and a solid basic substance, the second layer uses an adsorbent containing a solid acidic substance, and the third layer contains an activated carbon. A small-scale adsorption / regeneration experiment was conducted in which ambient air was used as regeneration air through an adsorbing tower composed of three layers of adsorbents and air mixed with the above components.
Next, 10 m ³ / min scale regeneration air is processed by the batch-type TSA device 10 shown in FIG. 2 and the temperature control and humidity control device 30 shown in FIG. 3, and a long-term repeated circulation supply test connected to a clean room is performed. As a result, the inventors have found that high-purity air can be prepared and completed the present invention.

[1] According to the present invention, exhaust from a clean work space such as a temperature-controlled and clean room, a clean chamber, and / or a mini-environment is purified as processing air and circulated and supplied to the clean work space. In this case, the treated air is passed through a temperature control and humidity control device, and then purified through a batch temperature swing adsorption device using air taken from indoors or outdoors as regeneration air, or the treated air is passed indoors. Alternatively, there is provided a cleaning method for clean room exhaust, characterized in that it is cleaned through a batch-type temperature swing adsorption device that uses air taken from outside as regenerative air, and is then passed through a temperature and humidity control device.
Specifically, the exhaust from the clean work space is taken in as processing air, particulate contaminants in the processing air are removed, and basic molecular contaminants and organic molecular contaminants and / or As a first specific means for cleaning to remove acidic molecular pollutants, exhaust from clean work spaces such as clean rooms, clean chambers, mini-environments, etc., is taken as process air into a temperature and humidity control device. After passing through, the pollutant in the processing air is further removed and purified through the batch temperature swing adsorption device (batch type TSA device) using the air taken from indoors or outdoors as regeneration air. Processed air that is exhausted from clean work spaces such as clean rooms, clean chambers, mini-environments, etc. After cleaning to remove these contaminants through the location, it is characterized in that the lead to the temperature and humidity control device.

  According to the present invention, a clean room that cleans exhaust from a clean work space such as a temperature-controlled and clean room, a clean chamber, and / or a mini-environment as process air, and circulates the air into the clean work space. This is an exhaust purification device that is composed of a temperature and humidity control device and a batch-type temperature swing adsorption device, and passes the treated air through the temperature and humidity control device, and then regenerates the air taken indoors or outdoors. Clean through a batch temperature swing adsorber used as air, or clean through a batch temperature swing adsorber that uses air taken indoors or outdoors as regeneration air, and then adjust it. A clean room exhaust cleaning device is provided which is connected to a temperature and humidity control device.

[2] In the present invention, the batch temperature swing adsorption device is an adsorption mode for removing basic molecular contaminants, organic molecular contaminants and / or acidic molecular contaminants in the treated air with an adsorbent. And the adsorbent unit in the regeneration mode for cooling and heating by passing regeneration air through the adsorbent unit adsorbing the basic, organic and / or acidic molecular contaminants. A system is provided with two systems (A) and (B) arranged in parallel, and air taken from indoors or outdoors is used as regeneration air, and a regeneration air cooling / heating unit that cools and heats the system, and [1] The clean room according to [1], further comprising a first valve and a second valve which are switching means between the system (A) and the system (B), which alternately repeats the adsorption mode and the regeneration mode. Air-cleaning method is provided.

  Further, in the present clean room exhaust purification device, the batch temperature swing adsorption device uses an adsorbent for the basic molecular contaminants and organic molecular contaminants and / or acidic molecular contaminants in the processing air. The system is in the regeneration mode in which it is cooled and heated by passing regeneration air through the adsorbent unit system in the adsorption mode to be removed and the adsorbent unit adsorbing the basic, organic and / or acidic molecular contaminants. Regenerative air cooling / heating which has two systems (A) and (B) arranged in parallel with the adsorbent unit system, and further uses air taken from indoors or outdoors as regenerative air to cool and heat it. And a clean room exhaust comprising a first valve and a second valve as switching means for (A) system and (B) system, which alternately repeat the adsorption mode and the regeneration mode. A cleaning apparatus.

[3] According to the present invention, the adsorbent unit is an adsorption unit using activated carbon and a solid basic substance that selectively adsorb organic molecular pollutants and acidic molecular pollutants on the first layer. Adsorbent layer b using material containing solid acidic substance that selectively adsorbs basic molecular contaminants on material layer a, second layer, and organic molecular contaminants selectively adsorbed on third layer It is comprised from the adsorbent layer c using the thing containing the activated carbon to perform, The cleaning method of the clean room exhaust | exhaustion of [2] characterized by the above-mentioned is provided.

  Further, in the present clean room exhaust cleaning apparatus, the adsorbent unit includes an activated carbon that selectively adsorbs organic molecular pollutants and acidic molecular pollutants and a solid basic substance on the first layer. The adsorbent layer a, the adsorbent layer b using a solid acid substance that selectively adsorbs basic molecular contaminants to the second layer, and the organic molecular contaminants selectively to the third layer This is a clean room exhaust cleaning device composed of an adsorbent layer c using an activated carbon adsorbed on the water.

[4] According to the present invention, the regeneration air cooling / heating unit recovers excess heat of the regeneration air intake, the regeneration air blower, the regeneration air cooler that is the refrigerant evaporator of the refrigeration cycle, and the high temperature regeneration air. A regenerative air preheater that preheats the regenerated air at normal temperature, and a regenerative air heater that has a function of controlling the temperature of the regenerated air flowing into the adsorbent unit in the regeneration mode to a set temperature selected from the range of 150 to 220 ° C. The clean room exhaust gas cleaning method according to [2], characterized in that the clean room exhaust gas is constituted.

  Further, in the present clean room exhaust purification apparatus, the regeneration air cooling / heating unit includes a regeneration air intake, a regeneration air blower, a regeneration air cooler that is a refrigerant evaporator of a refrigeration cycle, and excess heat of high temperature regeneration air. Is equipped with a function to control the temperature of the regeneration air flowing into the adsorbent unit in the regeneration mode to a set temperature selected from the range of 150 to 220 ° C. This is a clean room exhaust cleaning device composed of a regenerative air heater.

[5] According to the present invention, the inside of the first valve and the second valve is divided into four small chambers by a frame-type partition plate, and each of the small chambers is opened and closed by the rotation of the plate-like rotating valve body. The clean room exhaust cleaning method according to [2] is provided, which is a four-port automatic switching valve that repeatedly switches between the (A) system and the (B) system.

  Further, in the present clean room exhaust purification apparatus, the first valve and the second valve are internally partitioned into four small chambers by a frame-type partition plate, and each small chamber is opened by the rotation of the plate-like rotary valve body. The clean room exhaust cleaning device is a 4-port automatic switching valve that switches between the (A) system and the (B) system by repeatedly closing and closing.

[6] According to the present invention, in the batch-type TSA apparatus that uses the air taken from the inside or outside as regeneration air, when the adsorption mode is (A) system and the regeneration mode is (B) system, (A) Clean air that flows from the system through the second valve to the clean work space, and regenerated air that flows to the system through the second valve via the regeneration air cooling / heating unit (B), The clean room exhaust gas cleaning method according to [2] or [4] is provided, wherein the flow rate ratio is set in a range from 1: 1 to 1: 0.1.

  Further, in the present clean room exhaust purification apparatus, in the batch-type TSA apparatus using the air taken from the inside or outside as regeneration air, the adsorption mode is (A) system, and the regeneration mode is (B) system. In this case, (A) clean air that flows from the system through the second valve to the clean work space, and regenerated air that flows to the system through the second valve via the regeneration air cooling / heating unit (B) Is a clean room exhaust purifier set to a flow rate ratio selected from the range of 1: 1 to 1: 0.1.

The clean room exhaust gas purification method of the present invention uses a basic molecular form such as ammonia, triethylamine (TEA), trimethylamine (TMA), N-methylpyrrolidone (NMP), etc. generated during processing without using a chemical filter. Pollutants or basic and organic molecular pollutants, organic molecular pollutants such as cinna, toluene, xylene, propylene glycol monomethyl ether acetate (PGMEA), many kinds contained in the atmosphere organic molecular contaminants, Cl ^-, NOx, basic molecular contaminants acidic molecular contaminants as well as amines and ammonia SOx can be removed, thus, industrial waste can be greatly reduced, contributing to environmental improvement can do.

  In addition, since the clean room exhaust gas cleaning method of the present invention does not use a chemical filter, the heavy work of replacing a chemical filter that has reached the end of its life with a new one becomes unnecessary, and the operation of the equipment installed in the clean room is eliminated. There is no need to stop it, and it is possible to bring about an economic effect of reducing the variable cost in the production cost of the product that the cleanup energy required to restore the contaminated clean space to the clean state is also unnecessary.

  In the present invention, since a chemical filter is not used, the operating rate of the apparatus installed in the clean room is improved, and a spare work space that has been necessary in the prior art, that is, a spare clean room and an apparatus installed in the clean room, etc. There is no need to monitor molecular pollutants such as ammonia, and a great economic effect of reducing the fixed cost in the production cost of the product, that is, no monitoring device and personnel are required.

  Furthermore, the method for purifying exhaust from the clean work space according to the present invention contributes to the improvement of the operation rate and the yield of the product because the purified temperature-controlled air can be supplied semi-permanently and stably. be able to. Therefore, it can contribute to a significant reduction in the manufacturing cost of the product. In addition, exhaust from the clean work space is taken in as process air to remove particulate pollutants and molecular pollutants, temperature control and humidity are circulated and supplied to the clean work space. Compared with the enormous amount of energy required for the one-pass disposable method in which the same amount of air in the clean work space is discharged out of the system, the temperature control and humidity control energy for the clean work space such as the clean room of the present invention can be significantly reduced.

  In the present invention, the high-performance filter (1) 11 (FIGS. 1 and 2) is installed in the circulating air duct 55 (FIG. 1), and the exhaust from the clean work space is used as the processing air. The concentration of particulate contaminants has already been extremely reduced, and the high performance filter (2) 53 (FIG. 1) once attached can be used continuously and semipermanently and stably. Furthermore, even if the high performance filter (1) 11 (FIG. 2), the dust removal filter (1) 54 (FIGS. 1 and 6) and the regenerative air filter 21 (FIG. 2) are replaced, the operation in the clean work space is stopped. There is no need.

In the present invention, the solid acid layer which can be repeatedly reused and adsorbs the basic molecular pollutant with high selectivity, the organic molecular pollutant and the acidic molecular pollutant with high selectivity. Activated carbon layer adsorbed at the top and an adsorbent layer containing a solid basic substance upstream of the solid acid layer, and an activated carbon layer adsorbing organic molecular pollutants with high selectivity downstream of the solid acid layer. because using the adsorbent unit comprising three layers provided on the side, ammonia is a basic contaminant, respectively TEA and TMA 0.1 [mu] g / m ³ or less, NMP is 0.6 [mu] g / m ³ or less, the organic molecules form contaminants hexadecane conversion 3.2 [mu] g / m ³ or less, 2 nitric oxide is an acidic molecular contaminants (NO ₂₎ is 1.0 [mu] g / m ³ or less, Cl ^- is 0.01 [mu] g / m ³ or less and SOx (SO ₄ equivalent) to below the detection limit Permanently it can continuously stably removed.

  Furthermore, according to the present invention, when the organic molecular contaminant having a large molecular weight generated when the chemical filter (C) is used flows in pulsatingly, the molecular weight previously adsorbed is reduced. In the present invention, an adsorption / regeneration test using the treated air and the regenerated air is performed in addition to increasing the adsorption capacity by providing the adsorbent layer c in the present invention. In the present invention, the cycle time for switching from the suction mode to the regeneration mode and from the regeneration mode to the suction mode is set after confirming in advance that the suction capacity is in a sufficient state. .

  Since the batch type TSA apparatus in the present invention has the regeneration function with two adsorbent units (A) and (B) in parallel, the adsorption mode and the regeneration mode are alternately used for the (A) system and the (B) system. By switching repeatedly, clean room exhaust can be cleaned semi-permanently and stably.

Since the regeneration air used in the batch-type TSA apparatus in the present invention takes indoor or outdoor air and heats it to 150 to 220 ° C., ammonia that is a basic pollutant remaining in the adsorbent after desorption, each adsorption equilibrium partial pressure for the TEA and TMA 0.1 [mu] g / m ³ or less, NMP is 0.6 [mu] g / m ³ or less, the equilibrium partial pressure for the organic contaminants is 3.2 [mu] g / m ³ or less at hexadecane conversion, acid contamination The adsorption equilibrium partial pressure for the substance NO ₂ is at a level corresponding to 1.0 μg / m ³ or less.

  Since the batch type TSA apparatus according to the present invention includes the first valve and the second valve which are four-port automatic switching valves, the flow to the clean work space may be intermittent when the adsorption mode and the regeneration mode are switched alternately. There is no pressure fluctuation. Accordingly, when the flow rate ratio between the clean air and the regeneration air is 1: 1, no flow rate fluctuation occurs.

  Further, the batch type TSA apparatus of the present invention does not have complicated ducting, the apparatus is compact, and there is no mixing of processing air, clean air, and regeneration air. In addition, there is no stagnation or stagnation between the duct and valve, so there is no increase or fluctuation in the concentration of molecular pollutants in clean air, even when switching between adsorption mode and regeneration mode, and in steady state. Yes.

  Since the batch type TSA apparatus in the present invention is provided with two adsorbent units (A) and (B) and a regeneration mechanism in parallel, the adsorption system and the regeneration mode are alternately used for the (A) system and the (B) system. By switching repeatedly, clean room exhaust can be cleaned continuously and stably over a long period of time.

  In addition, since the regenerative air used in the batch-type TSA apparatus in the present invention is indoor or outdoor air, the total amount of exhaust air circulated from the clean work space is not limited to particulate pollutants and organic, but basic and acidic. Molecular contaminants can be removed and cleaned, and temperature and humidity can be adjusted and supplied to a clean work space.

As the temperature control apparatus in the present invention, an industrial air conditioner already proposed by the applicant of the present invention in JP-A-2004-28421 can be suitably applied.

  The industrial air conditioner includes a measuring means for measuring the total pressure of the environment, the flow rate or flow rate of the processing air or the total pressure of the blower, the temperature and the related humidity of the processing air, the related humidity and the static pressure of the circulating supply air, and the measuring means. Because it is an air conditioner that uses a refrigeration cycle provided with a calculation means for calculating a necessary cooling and dehumidifying amount, a necessary cooling and dehumidifying heat amount, a necessary humidifying amount and a necessary humidifying heat amount by inputting a measurement value obtained using The amount of energy required for temperature control and humidity control can be reduced more than before.

(First Embodiment)
Hereinafter, a first embodiment for carrying out the present invention will be described with reference to the drawings. FIG. 1 shows that exhaust from the clean working space 50 is taken as processing air from the processing air inlet 1 and is cleaned by removing particulate contaminants and molecular contaminants in the processing air, and further adjusting the temperature. FIG. 3 is a configuration diagram of an embodiment of the present invention in which humidity is adjusted to form purified temperature-controlled air and circulated from the cleaned temperature-controlled air supply port 2 to the clean work space 50;

  In FIG. 1, a batch-type TSA apparatus 10 provided with a regenerative air cooling and heating unit 28 and a temperature control are arranged between the processing air introduction port 1 and the purified temperature control and humidity control air supply port 2 in the order that the processing air flows. A dampening device 30 is arranged.

  Further, the configuration of the batch-type TSA apparatus 10 is shown in FIG. The processing air flows from the processing air inlet 1 into the high-performance filter (1) 11 that removes the particulate contaminants, and then passes through the first valve 12 and is in the adsorption mode (A) system adsorbent unit (A ) Inflow into 13A.

(Adsorbent layers a, b, c)
In the present invention, the adsorbent unit (A) 13A and the adsorbent unit (B) 13B each have three adsorbent layers a to c arranged in series and integrated.
The first layer (a) contains activated carbon that selectively adsorbs organic substances and acidic substances and a solid basic substance, and is processed into a honeycomb, corrugated, or pleated shape so as to minimize pressure loss during ventilation. And it consists of the adsorbent layer a which laminated | stacked the molding further prepared by baking. Examples of the activated carbon include activated coke, graphite, carbon, activated carbon fiber, and the like. As the solid basic substance, magnesium oxide, magnesium silicate, calcium silicate, sepiolite, alumina, zeolite and the like can be used.
The second layer (b) contains a composite oxide such as titanium and silicon, which is a solid acidic substance that selectively adsorbs a basic substance, and vanadium oxide. It consists of an adsorbent layer b in which molded articles prepared by corrugated or pleated processing and further baked are laminated.
The third layer (c) contains activated carbon that mainly adsorbs organic substances, is processed into a honeycomb, corrugated or pleated shape so as to minimize pressure loss during ventilation, and is further fired and prepared. It consists of the adsorbent layer c which laminated | stacked the molded object which carried out.

From the processing air flowing into the adsorbent unit (A) 13A, while passing through the adsorbent layer a, organic molecular pollutants having a relatively large molecular weight and Cl ⁻ , NOx, SOx and the like derived from the environmental atmosphere While acidic molecular pollutants are removed and then pass through the adsorbent layer b, ammonia and basic and organic molecular pollutants TMA, TEA, NMP, and other amines are removed and further adsorbed. While passing through the material layer c, organic molecular contaminants that are not adsorbed and removed by the adsorbent layer a and still remain in the processing air, and TMA, TEA, which are not adsorbed and removed by the adsorbent layer b, NMP is removed.

In the treated air flowing out from the adsorbent unit (A) 13A, ammonia as a basic molecular pollutant is 0.1 μg / m ³ or less, TEA and TMA are each 0.1 μg / m ³ or less, and NMP is 0 .6μg / m ³ or less, organic molecular contaminants hexadecane conversion 3.2 [mu] g / m ³ or less, the nitrogen oxides are acidic molecular contaminants (NO ₂₎ is 1.0 [mu] g / m ³ or less, Cl ^- is 0.01 μg / m ³ or less and SOx are removed to the detection limit or less. The clean air thus obtained flows into the temperature and humidity control apparatus 30 from the clean air outlet 16 through the second valve 15.

  The clean air that has flowed into the temperature and humidity control apparatus 30 is adjusted so that the temperature and humidity control conditions of the clean air satisfy the requirements of the clean work space 50. That is, the dehumidification is performed by first flowing into the cooling dehumidifier 32 shown in FIG. Usually, the saturation humidity is adjusted to a dew point in the range of 4 to 17 ° C. Subsequently, it is made to flow into the warmer 33 and is normally heated to 15-30 degreeC. Furthermore, it is made to flow into the humidifier 34 and humidification adjustment is carried out to the relative humidity which is normally in the range of 35 to 50%. The humidity control water is taken from the humidity control water intake 3 to evaporate a necessary amount of water. The clean air, which has been temperature-controlled and humidity-controlled, is pressurized by a purified temperature-controlled and humidity-controlled air blower (1) 35 and is supplied from the purified temperature-controlled and humidity-controlled air supply port 2 to a clean work space 50 such as a clean room, clean chamber, and mini-environment. To supply.

  With conventional temperature and humidity control devices, the total pressure of the environment (usually atmospheric pressure) is standard even if this device is installed at a position 600 meters above sea level, regardless of the weather and seasonal changes. Humidity adjustment is performed by a method of controlling the relative humidity as being atmospheric pressure. Therefore, it cannot follow the fluctuation | variation of the required energy amount accompanying the fluctuation | variation of atmospheric pressure, and the fluctuation | variation of absolute humidity. Incidentally, since the daily fluctuation (24 hours) of atmospheric pressure is approximately 20 to 50 hPa, the absolute humidity varies by 2 to 5%. That is, even if the relative humidity is constant, the absolute humidity varies. For processing operations in a clean room targeted by the present invention, it is necessary to supply purified temperature-controlled air with a constant absolute humidity rather than a relative humidity. Therefore, in the embodiment of the present invention, it is preferable to apply the industrial air conditioner disclosed in the aforementioned Japanese Patent Application Laid-Open No. 2004-28421.

  That is, the industrial air conditioner proposed by the present inventors, as shown in FIG. 3, is the flow rate, static pressure, temperature and relative humidity of the clean air at the clean air outlet 16, and the purified conditioned air. A flow rate sensor (1) 41, a static pressure sensor (1) 42, a temperature sensor (1) 43, and a related humidity sensor, which are measuring means for measuring the flow rate, static pressure, temperature and related humidity in the supply port 2 and the total pressure of the environment. (1) 44, flow rate sensor (2) 45, static pressure sensor (2) 46, temperature sensor (2) 47, relative humidity sensor (2) 48, atmospheric pressure (total pressure) sensor 49 are installed and measurement obtained It is a temperature / humidity adjusting device including a calculating means 40 for inputting a value and calculating a required amount of humidified water, a humidifying water pump 37 that operates according to a control signal obtained by converting the amount of humidified water, and a mini-boiler 36 that evaporates all the amount of water. .

  In the clean work space 50, as shown in FIG. 1, a high performance filter (2) 53 and a filter fan (2) 52 for final preparation of a cleanliness class are installed near the outlet 56, In the vicinity of the air intake port 57, a dust filter (1) 54, an intake air fan (1) 58, and a circulation for circulating the exhaust from the clean work space to the batch-type TSA device 10 and the temperature and humidity control device 30 are provided. A blower 51 and a circulating air duct 55 are installed.

Here, the reproduction operation of the batch-type TSA apparatus according to the present invention will be described with reference to FIG. When the adsorption mode is the (A) system, the regeneration mode is the (B) system. Therefore, the regeneration air is taken into the clean air flowing from the system (A) through the second valve 15 to the clean air outlet 16. The regenerated air flowing from the second valve 15 to the system (B) through the regenerative air cooling / heating unit 28 from the port 26 is introduced at a flow rate ratio in the range of 1: 1 to 1: 0.1.
Here, as the regeneration air flow rate is larger than the clean air flow rate, the regeneration operation can be completed in a shorter time. However, it is necessary to increase all the device capabilities of the regeneration air cooling and heating unit 28, and the batch-type TSA device is It is not compact and the equipment cost increases. Further, since the regeneration air discharge port 27 is connected to an exhaust gas treatment device (not shown), the greater the regeneration air flow rate, the less the concentration of contaminants that are desorbed, and the greater the collection efficiency of the exhaust gas treatment device. descend. Furthermore, when the regeneration air is heated to 150 to 220 ° C., the volumetric flow rate of the regeneration air is 1.4 to 1.7 times that of room temperature due to thermal expansion, so that the pressure loss increases and the air flow at that time The energy required for this increases as the amount of regenerated air increases.

  Conversely, the smaller the regenerative air flow rate is relative to the clean air flow rate, the longer the regenerative operation time will be, but the regenerative air cooling / heating unit 28 does not need to have a large equipment capacity. Can be made compact. Naturally, the device manufacturing cost can also be reduced. Moreover, the collection efficiency of the exhaust gas treatment device is also improved. Furthermore, there is little pressure loss and blowing energy when the regeneration air is heated to 150 to 220 ° C. However, the smaller the regenerative air flow rate, the lower the flow rate sufficient to expel the adsorbed material desorbed as the regenerated air amount flowing in the adsorbent layer. At the same time, drift, stagnation and stagnation occur in the adsorbent unit and in the duct. Since the concentration of molecular pollutants at the stagnant or stagnant area is higher than that in clean air, switching to the adsorption mode will push the contaminated air into the clean room by being pushed out by the processing air with a high flow rate. Become.

In consideration of the above, in the batch-type TSA apparatus according to the present invention, the flow rate ratio of the regeneration air to the clean air is preferably in the range of 1: 1 to 1: 0.1. More preferably, it is in the range of 1: 0.8 to 1: 0.3.
As a precaution, the regeneration air in the present invention refers to heated air that is sent to the adsorbent unit for which the adsorption mode has ended, and a process of desorbing impurities adsorbed from the adsorbent unit by the heated air ( This is the air used for the regeneration mode.

  The regeneration mode is composed of a heating time zone and a cooling time zone. When the regeneration mode is in the heating time zone, the regeneration air flows from the regeneration air intake 26 and passes through the regeneration air filter 21 and the regeneration air blower. In the heating time zone, the pressure is increased by 22 and the refrigerant is passed through the regenerative air cooler 23 in which the refrigerant is not circulated. Then, excess heat of the high-temperature regeneration air is recovered. Accordingly, the regeneration air itself is preheated from room temperature to 100 to 170 ° C. Next, the regeneration air flows into the regeneration air heater 25, is heated to a set temperature selected from the range of 150 to 220 ° C., and flows from the second valve 15 into the adsorbent unit (B) 13B.

The adsorbent is heated by the regeneration air heated to 150 to 220 ° C. flowing into the adsorbent unit (B) 13B, and is adsorbed to the adsorbent at room temperature when the system (B) is in the adsorption mode in the previous cycle. The basic, organic, and acidic pollutants that have been removed are desorbed and mixed in the stream of high-temperature regeneration air. At this time, organic pollutants having a relatively large molecular weight and acidic pollutants such as Cl ⁻ , NOx, and SOx are desorbed from the adsorbent layer a and contaminated with ammonia and basic and organic TMA, TEA, and NMP. Substances are desorbed from the adsorbent layer b, and organic pollutants and acidic pollutants that are not adsorbed by the adsorbent layer a and TMA, TEA, and NMP that are not adsorbed by the adsorbent layer b are removed from the adsorbent layer c. Detached.

  As the first valve and the second valve used in the present invention, it is preferable to use a 4-port automatic switching valve. An explanatory diagram of it is shown in FIG. 7-8. The 4-port automatic switching valve 90 is a valve proposed by the applicants of the present invention in Japanese Patent Laid-Open No. 2006-300394. In detail, such a 4-port automatic switching valve can be implemented by incorporating the contents described in detail in the publication.

  In the embodiment of the present invention, the first valve 12 (FIG. 2) and the second valve 15 (FIG. 2) include a housing portion 91 having a space inside, and the space portion including four small chambers R1, R2, A frame-shaped partition plate 93 having an opening 92 partitioned into R3 and R4, a plate-shaped rotary valve body 94 for opening or closing the opening 92 of the frame-shaped partition plate 93, and 4 attached to the housing 91. Two ports (inflow port L1 for always allowing gas to flow in, inflow / outlet port (1) L2 for alternately flowing in and out of fluid), outflow port L3 for always flowing out gas, and alternately inflow and outflow of gas with L2. An inflow / outlet port (2) L4) and driving means 96 for rotating the plate-like rotary valve element 94 around the rotary shaft 95 are provided. The members constituting the casing 91, the frame-shaped partition plate 93, the rotating shaft 95, and the plate-like rotary valve body 94 preferably have a heat insulating function, and all have the same shape, A four-port automatic switching valve of the size is preferred.

(Second Embodiment)
Next, the 2nd aspect for implementing this invention is demonstrated along FIG. The exhaust from the clean work space 50 is taken as processing air from the processing air inlet 1 to remove particulate pollutants in the processing air, and after passing through the temperature and humidity control device 30, the batch type TSA device 10 is used to remove the molecular pollutant to obtain purified temperature-controlled humidity air, which is circulated from the purified temperature-controlled humidity air supply port 2 to the clean work space 50. It is a block diagram of the embodiment.

  In FIG. 6, a batch provided with a temperature and humidity control device 30 and a regenerative air cooling and heating unit 28 in the order in which the processing air flows between the processing air introduction port 1 and the purified temperature and humidity control air supply port 2. A type TSA apparatus 10 is arranged. The processing air flows from the processing air inlet 1 into the high-performance filter (1) 11 that removes particulate contaminants, and then flows into the temperature and humidity control device 30.

The details of the adsorbent unit (A) 13A and the adsorbent unit (B) 13B in the present embodiment are the same as those described above, and from the temperature-controlled humidity air flowing into the adsorbent unit (A) 13A. While passing through the adsorbent layer a, organic molecular pollutants having a relatively large molecular weight and acidic molecular pollutants such as Cl ⁻ , NOx, SOx derived from the ambient air are removed, and then the adsorbent layer b is removed. During the passage, ammonia and basic and organic molecular contaminants TMA, TEA, NMP, and other amines are removed and further adsorbed by the adsorbent layer a while passing through the adsorbent layer c. The organic molecular contaminants that are not removed but still remain in the processing air and the TMA, TEA, and NMP that are not adsorbed and removed by the adsorbent layer b are removed.

  The process air that has flowed into the temperature and humidity control apparatus 30 shown in FIG. 6 is prepared so that the temperature and humidity control conditions of the clean air satisfy the requirements of the clean work space 50. An explanatory view of the temperature and humidity control apparatus 30 is shown in FIG. That is, it cools and dehumidifies by flowing into the cooling dehumidifier 32. Usually, the saturation humidity is adjusted to a dew point in the range of 4 to 17 ° C. Subsequently, it is made to flow into the warmer 33 and is normally heated to 15-30 degreeC. Furthermore, it is made to flow into the humidifier 34 and is humidified and adjusted to the relative humidity which is usually in the range of 35 to 50%. The humidity control water is taken from the humidity control water intake 3 and stored in the humidified water tank 38. The required amount of humidified water is evaporated by flowing into the mini-boiler 36 via the humidified water pump 37 operated by a control signal obtained by converting the necessary amount of humidified water obtained by the calculation means 40. The temperature-controlled and humidity-controlled air is boosted by the temperature-controlled humidity-controlled air blower 35 and flows into the batch-type TSA device 10 (FIG. 6).

  The temperature and humidity control apparatus 30 in the present embodiment is the same as that described above. However, although not shown, the flow velocity sensor (1), the static pressure sensor (1), the temperature sensor (1), and the related humidity sensor (1) are installed in the processing air introduction port 1 shown in FIG.

  Further, the configuration of the batch-type TSA apparatus 10 of FIG. 6 is shown in FIG. The treated air whose temperature has been adjusted is caused to flow from the first valve 12 to the adsorbent unit (A) 13A of the system (A) in the adsorption mode. After adsorbing and removing the molecular contaminants with the adsorbent unit (A) 13A, it becomes purified temperature-controlled air, and passes through the second valve 15 to be the purified temperature-controlled air blower (2) 17 (FIG. 6). The pressure is raised and supplied to the clean work space 50 from the purified temperature-controlled and humidity-controlled air supply port 2.

The details of the adsorbent unit (A) 13A and the adsorbent unit (B) 13B in the second embodiment are the same as those described above, and the temperature-controlled humidity air flowing into the adsorbent unit (A) 13A The organic molecular pollutants and acidic molecular pollutants having a relatively large molecular weight are removed while passing through the adsorbent layer a, and ammonia and basic and organic substances are then passed through the adsorbent layer b. Molecular contaminants such as TMA, TEA, NMP, and other amines are removed, and while passing through the adsorbent layer c, they are not adsorbed and removed by the adsorbent layer a, but remain in the processing air. Organic molecular pollutants that are not adsorbed and removed by the adsorbent layer b, and acidic molecular pollutants such as Cl ⁻ , NOx, and SOx that are derived from the ambient atmosphere are removed.

In the treated air flowing out from the adsorbent unit (A) 13A, ammonia as a basic molecular pollutant is 0.1 μg / m ³ or less, TEA and TMA are each 0.1 μg / m ³ or less, and NMP is 0 .6μg / m ³ or less, organic molecular contaminants hexadecane conversion 3.2 [mu] g / m ³ or less, the nitrogen oxides are acidic molecular contaminants (NO ₂₎ is 1.0 [mu] g / m ³ or less, Cl ^- is 0.01 μg / m ³ or less and SOx are removed to the detection limit or less. That is, the processing air becomes a purified temperature-controlled humidity air equivalent to that in the above-described first embodiment, and the purified temperature-controlled air passes through the second valve 15 and is cleaned and temperature-controlled. The pressure is increased by the humid air blower (2) 17 (FIG. 6) and supplied to the clean work space 50 from the purified temperature / humidifier air supply port 2.

  In the clean work space 50, a high performance filter (2) 53 for final preparation of cleanliness class is provided near the outlet 56, and a dust filter (1) 54 is provided near the filter fan 52 and the air intake 57. An air fan (1) 58, a circulation fan 51 and a circulation air duct 55 for circulating the exhaust from the work space to the temperature and humidity control device 30 and the batch-type TSA device 10 are installed.

  The clean room exhaust gas purification method of the present invention uses molecular pollutants such as ammonia, triethylamine (TEA), trimethylamine (TMA), N-methylpyrrolidone (NMP), etc. generated during processing without using a chemical filter. Can be removed continuously and stably over a long period of time, which can contribute to the environmental improvement of drastically reducing industrial waste. In addition, since no chemical filter is used, the heavy work of replacing the chemical filter with a new one becomes unnecessary, and it can bring about a great economic effect to reduce the variable cost in the semiconductor manufacturing cost. Is extremely large.

It is a block diagram of the cleaning apparatus in embodiment of this invention. It is a block diagram of the batch type TSA apparatus in this invention. It is explanatory drawing of the temperature control humidity control apparatus in this invention. It is a block diagram of the batch type TSA apparatus by a prior art. It is explanatory drawing of the cleaning apparatus by a prior art. It is a block diagram of the cleaning apparatus in another embodiment of this invention. It is explanatory drawing of the 4 port automatic switching valve in this invention. It is explanatory drawing of the 4 port automatic switching valve in this invention.

Explanation of symbols

1: treated air introduction port 2: purified temperature-controlled humidity-controlled air supply port 3: humidity-controlled water intake 10: batch-type TSA device 11: high-performance filter (1)
12: 1st valve | bulb 13: Adsorbent unit 15: 2nd valve | bulb 16: Clean air delivery port 17: Clean temperature-control humidity air blower (2)
21: regeneration air filter 22: regeneration air blower 23: regeneration air cooler 24: regeneration air preheater 25: regeneration air heater 26: regeneration air intake 27: regeneration air discharge port 28: regeneration air cooling / heating unit 30: Temperature control / humidity control device 32: Cooling dehumidifier 33: Heater 34: Humidifier 35: Purified temperature control humidity control air blower (1)
36: Mini boiler 37: Humidification water pump 38: Humidification water tank 40: Calculation means 41: Flow rate sensor (1)
42: Static pressure sensor (1)
43: Temperature sensor (1)
44: Related humidity sensor (1)
45: Flow rate sensor (2)
46: Static pressure sensor (2)
47: Temperature sensor (2)
48: Related humidity sensor (2)
49: Atmospheric pressure (total pressure) sensor 50: Clean work space 51: Circulating fan 52: Filter fan (2)
53: High performance filter (2)
54: Dust removal filter (1)
55: Circulating air duct 56: Air outlet 57: Air intake port 60: Conventional temperature control device 61: High performance filter (3)
62: Conventional cooling and dehumidifying device 63: Conventional heating device 64: Conventional humidifying device 66: Purified temperature-controlled humidity air blower (1)
80: Chemical filter unit 81: Chemical filter (A1)
82: Chemical filter (B1)
83: Chemical filter (C1)
84: Clean air blower 90: 4-port automatic switching valve 91: Housing 92: Opening 93: Frame-shaped partition plate 94: Plate-shaped rotary valve body 95: Rotating shaft 96: Driving means 100: Clean room 101 according to the prior art : Clean temperature control humidity air blower (3)
102: Dust removal filter (2)
103: Circulating air blower 104: Circulating air duct 105: Clean temperature-controlled humidity air outlet 107: Air intake (2)
108: Intake air fan (2)
110: Fan filter unit 111: Chemical filter (A2)
112: Chemical filter (B2)
113: Chemical filter (C2)
114: Filter fan (1)
115: High performance filter (4)
120: Prior art batch-type TSA device L1: Inflow port L2: Inflow / outflow port (1)
L3: Outflow port L4: Inflow / outflow port (2)
T1 to T8: Branch / merge joints V1 to V8: On-off valves R1 to R4: Small chamber

Claims (6)

  When the exhaust from a clean work space such as a temperature-controlled and clean room, clean chamber, and / or mini-environment is purified as process air and circulated and supplied to the clean work space, the process air is conditioned. It passes through a humidity control device, and then passes through a batch-type temperature swing adsorption device that uses air taken from indoors or outdoors as regeneration air, or a batch type that uses air taken from indoors or outdoors as regeneration air. A clean room exhaust gas cleaning method comprising: passing through a temperature swing adsorption device; and then passing through a temperature control humidity control device.   The batch temperature swing adsorption device is a system of adsorbent units in an adsorption mode for removing basic molecular contaminants and organic molecular contaminants and / or acidic molecular contaminants in the processing air with an adsorbent, In addition, an adsorbent unit system in a regeneration mode in which regeneration air is cooled and heated by passing regeneration air through the adsorbent unit adsorbing the basic, organic and / or acidic molecular contaminants is arranged in parallel (A). , (B), and a regenerative air cooling / heating unit that cools and heats the air taken from indoors or outdoors as regenerative air, and alternately repeats the adsorption mode and the regeneration mode. 2. The clean room exhaust gas purifying method according to claim 1, further comprising a first valve and a second valve which are switching means between the system and (B) system.   The adsorbent unit includes an adsorbent layer a using activated carbon and a solid basic substance that selectively adsorb organic molecular pollutants and acidic molecular pollutants on the first layer, and a base on the second layer. Adsorbent layer b using a solid acidic substance that selectively adsorbs organic molecular contaminants, and adsorption using activated carbon that selectively adsorbs organic molecular contaminants in the third layer 3. The method for cleaning clean room exhaust according to claim 2, comprising a material layer c.   The regeneration air cooling / heating unit is a regeneration air intake, a regeneration air blower, a regeneration air cooler that is a refrigerant evaporator of a refrigeration cycle, and a regeneration that preheats room temperature regeneration air by recovering excess heat of high temperature regeneration air. An air preheater and a regeneration air heater having a function of controlling the temperature of regeneration air flowing into the adsorbent unit in the regeneration mode to a set temperature selected from a range of 150 to 220 ° C. The method for cleaning clean room exhaust according to claim 2.   The first valve and the second valve are internally divided into four small chambers by a frame-shaped partition plate, and each of the small chambers is repeatedly opened and closed by the rotation of the plate-shaped rotating valve body, and the system (A) 3. The clean room exhaust gas cleaning method according to claim 2, wherein the system is a 4-port automatic switching valve for switching the system.   When the adsorption mode is the (A) system and the regeneration mode is the (B) system, the clean air flowing from the system (A) through the second valve to the clean work space and the regeneration air cooling / heating The regeneration air flowing through the second valve and passing through the second valve to the system (B) is set to a flow rate ratio selected from the range of 1: 1 to 1: 0.1. Or the clean room exhaust gas cleaning method according to 4.

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