JP2004358436A - Apparatus for removing contaminant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for removing contaminants which restrains from growing and also is reduced in cost. <P>SOLUTION: Numeral 50 is an air washer device by which a return air (25°C) from a clean room is introduced. Numeral 51 is a HEPA (high-efficiency particulate air) filter provided at the entrance of the air washer device 50. Numeral 52 is a cold water coil. Numeral 53a to numeral 53c are spray nozzles. Numeral 55 is a supplementary circulation tank, which is divided into a first supplementary circulation tank 55a and a second supplementary circulation tank 55c. The return air, further, passes through an eliminator 54 to remove mist of sprayed water and flows into an air conditioning chamber 60 at a lower temperature of 12°C. Three heat exchangers consist of a spray heat exchanger 58a, a refilling water heat exchanger 58b and a hot water heat exchanger 58c are connected in series and installed. Supply cold water (E) has a temperature of 7°C. Cold water is arranged so as to be used from low temperature to high temperature in high order of energy. A temperature of cold water (G) supplied to the cold water coil 52 is 12°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a contaminant removal apparatus for removing contaminants present in air in a clean room or the like.
[0002]
[Prior art]
In a clean room that manufactures semiconductors and liquid crystals, etc., in areas where processes such as semiconductor, liquid crystal cleaning, exposure, and coating processes are performed, organic chemical gases that are vaporized from chemicals used in the production process Is contained in the air. The organic substances in the air have to be removed because they adversely affect the working environment of the clean room and the product yield. The present applicant has proposed a method of removing organic substances and the like in the air from a clean room in Patent Document 1. FIG. 2 is an explanatory diagram of the organic substance removing method described in Patent Document 1.
[0003]
In FIG. 2, a clean room 1 is installed in a factory for manufacturing semiconductors and liquid crystals, for example. In the manufacturing apparatus 2, for example, semiconductors and liquid crystals are manufactured. The wet-type pollutant gas removal device 3 is configured to contact the air from which pollutants are to be removed with make-up water such as pure water, and remove the contaminants by absorption and dissolution into the make-up water. As described above, the wet contaminated gas removing device 3 removes the contaminants by sucking the indoor air of the clean room 1 containing the contaminants such as the organic gas leaked from the manufacturing device 2, and removes the purified air by the blowing fan 6. Circulate in the clean room 1.
[0004]
As described above, the indoor air in the clean room 1 is sucked by the wet-type contaminant gas removing device 3 to remove peculiar contaminants existing in the air, and the purified air is circulated to the clean room 1 again. In the wet pollutant gas removal device 3, pure water is cooled by cold water in the spray water tank 5, and the low-temperature water is used to contact the processing air with the spray nozzle 4 in the spray chamber 7 to remove contaminants. Improves performance. The reason for using low-temperature water is that low-temperature water increases the absorption efficiency of substances. The air after the treatment is used for air conditioning (cooling and humidity control) in the clean room.
[0005]
Note that filters 8 and 9 are provided at the inlet and outlet of the spray chamber 7 to remove microparticles containing bacteria. As the filter 8, for example, a high-performance filter (High Efficiency Air Filter) or a HEPA filter (High Efficiency Particulate Rate Air Filter) is used. Further, a HEPA filter is used as the filter 9.
[0006]
By the way, in the wet contaminated gas removing device 3, when the operating conditions are as follows, microorganisms (bacteria) propagate on the spray nozzle 4, its piping, the inner wall surface of the spray chamber 7, and the like. That is, (1) the internal temperature of the spray chamber 7 is high. (2) Bacteria enter the spray chamber 7. (3) The concentration of the organic substance sucked into the spray chamber 7 is extremely high, so that the organic substance is likely to be eaten by bacteria.
[0007]
If bacteria grow on the spray nozzle 4, its piping, the inner wall surface of the spray chamber 7, and the like under such conditions, problems such as a decrease in contaminant removal performance and a decrease in the amount of spray water occur. Various countermeasures have been taken to prevent the propagation of such bacteria, and regular maintenance is required. As an example of the countermeasure, the air temperature in the spray chamber 7 is reduced.
[0008]
[Patent Document 1]
JP-A-2000-33221
[Problems to be solved by the invention]
In the conventional apparatus shown in FIG. 2 described in Patent Document 1, the air temperature in the spray chamber 7 is reduced only by a large amount of spray water. For this reason, a large amount of cooling water is required to secure a required temperature. Therefore, in addition to the cost of the cooling water itself, there is a problem that the cost of equipment increases due to an increase in the size of a heat source device for obtaining the cooling water, an increase in the diameter of a pipe through which the cooling water flows, and the like. Was.
[0010]
In addition, when the necessary temperature difference cannot be secured because the air temperature in the spray chamber 7 does not drop sufficiently, bacteria easily grow and the maintenance cost for restoring the breeding becomes high, which causes a problem. there were. Furthermore, there is a problem that the amount of water resources and energy used is large, and it is difficult to contribute to the global environment.
[0011]
The present invention has been made in view of such a problem, and an object of the present invention is to provide a contaminant removing apparatus that can reduce the cost and suppress the growth of bacteria.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, a contaminant removal apparatus according to the present invention includes a spray chamber having a plurality of rows of spray nozzles, a replenishing circulating water tank connected to the spray chamber and a collecting pipe, and supplied with make-up water. And a contaminant removal device that connects the spray nozzle and the replenishing circulating water tank with piping to remove contaminants in air that has flowed into a spray chamber by circulating water ejected from the spray nozzle,
A cooling means for lowering the temperature of the inflowing air is provided in the spray chamber.
[0013]
Further, the present invention is characterized in that a filter is provided in a stage preceding the cooling means.
[0014]
Further, the invention is characterized in that the cooling means is constituted by a chilled water coil, and the chilled water coil is provided on an inlet side of the spray chamber.
[0015]
Further, the contaminant removing apparatus of the present invention includes a spray chamber having a plurality of rows of spray nozzles, a replenishing circulating water tank connected to the spray chamber with a water collecting pipe and supplied with make-up water, the spray nozzle and the replenishing tank. A contaminant removing device that connects a circulating water tank with a pipe to remove contaminants in air that has flowed into the spray chamber by circulating water ejected from the spray nozzle,
A first heat exchanger into which the circulating water from the make-up circulating water tank flows, and a second heat exchanger into which the make-up water flows, wherein the plurality of rows of the spray nozzles are provided from the first heat exchanger. While supplying low-temperature circulating water to a part, low-temperature make-up water is supplied from the second heat exchanger to the make-up circulating water tank, and cold water is supplied to the first heat exchanger and the second heat exchanger. It is characterized by being connected in series by a flowing pipe.
[0016]
Further, the present invention is characterized in that a spray nozzle to which low-temperature circulating water is supplied from the first heat exchanger is provided on an outlet side of the spray chamber.
[0017]
Further, the present invention is characterized in that an air-conditioning room is installed on the outlet side of the spraying room, and air whose temperature is controlled cleanly from the air-conditioning room is supplied to a working room.
[0018]
The present invention also provides a third heat exchanger outside the air conditioning room, which is connected in series with a pipe through which the second heat exchanger and cold water flow, and the third heat exchanger is provided with the air conditioning. The hot water used for reheating the air in the room is passed through, and the cold water that has passed through the second heat exchanger is adjusted to a predetermined temperature and supplied to the cooling coil installed in the spray chamber. It is characterized by doing.
[0019]
Further, the present invention provides the second heat exchanger, which supplies cold water to the first heat exchanger, and is connected in series with the first heat exchanger by a pipe, and the second heat exchanger. The chilled water flows through the third heat exchanger connected in series with a vessel and piping.
[0020]
In the present invention, the temperature of the cold water supplied from each of the heat exchangers is the lowest of the temperature of the cold water supplied from the first heat exchanger, and the temperature of the cold water supplied from the third heat exchanger. Is characterized by the highest water temperature.
[0021]
In the present invention, since a cooling means for lowering the temperature of the air flowing into the spray chamber is provided in the spray chamber to lower the temperature, the amount of cold water used can be reduced, and the propagation of bacteria can be suppressed. Further, since a plurality of heat exchangers are connected in series by pipes, space required for installing the heat exchangers can be saved.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described. FIG. 1 is a schematic configuration diagram showing a contaminant removal apparatus of the present invention. 1, reference numeral 50 denotes an air washer device, which corresponds to the spray chamber 7 in FIG. Return air (air) containing contaminants from a clean room (working room) flows into the air washer device 50. Reference numeral 51 denotes a HEPA filter installed at an inlet of an air washer device (spray chamber) 50. Note that a high-performance filter may be provided instead of the HEPA filter.
[0023]
52 is a chilled water coil that cools the return air that has passed through the HEPA filter 51. The cold water coil 52 is used as a dry coil in which bacteria do not easily propagate. As will be described later, cold water at 12 ° C. is supplied to the cold water coil 52. In this case, since the cold water coil 52 does not condense, a condition under which bacteria grow in the cold water coil does not occur. As described above, since the filter for removing microparticles containing bacteria is provided at the inlet of the air washer device 50, and the temperature is lowered by installing the cold water coil at the subsequent stage of the filter, the propagation of bacteria is double protected. It is prevented by.
[0024]
The air washer device 50 is provided with a plurality of rows of spray nozzles 53a to 53c from the upstream side to the downstream side as viewed from the direction of the return air flow. The spray nozzles 53a to 53c inject low-temperature water into the return air that has flowed into the air washer device 50, thereby removing gas components having high solubility in water. Reference numeral 55 denotes a replenishing circulation water tank, which is connected to the air washer device 50 by water collecting pipes 70 and 71.
[0025]
The supply circulation water tank 55 is divided into a first supply circulation water tank 55a and a second supply circulation water tank 55b. 56a and 56b are first and second pumps, and 57a and 57b are first and second water treatment filters. The first supply circulating water tank 55a supplies circulating water to the spray nozzles 53a and 53b through a first pump 56a, a first water treatment filter 57a, and a pipe 72. The second replenishing circulating water tank 55b supplies circulating water to the spray nozzle 53c through a second pump 56b, a second water treatment filter 57b, a spray heat exchanger 58a, and a pipe 73.
[0026]
The low-temperature water injected by the spray nozzle 53c is collected by the collecting pipe 71 into the second replenishing circulating water tank 55b, and the surplus recovered water flows into the first replenishing circulating water tank 55a. The circulating water from the first replenishing circulating water tank 55a is ejected as low-temperature water by the spray nozzles 53a and 53b, and is collected by the collecting pipe 70 into the first replenishing circulating water tank 55a. Part of the recovered water flows out as wastewater, and the organic components absorbed by the air washer device 50 are discharged. As described above, the circulating water supplied from the first replenishing circulating water tank 55a to the spray nozzles 53a and 53b is the recovered water once used by the spray nozzle 53c, and thus is smaller than the circulating water supplied from the spray nozzle 53c. Purity is reduced.
[0027]
In the air washer device 50, an eliminator 54 is provided downstream of the spray nozzle 53c. The return air from which the gas components having high solubility in water have been removed by the spray nozzles 53a to 53c further passes through the eliminator 54 to remove the mist of the spray water. An air conditioning chamber 60 is provided adjacent to the air washer device 50, and the return air from which contaminants have been removed by the air washer device 50 flows into the air conditioning chamber 60.
[0028]
In the embodiment of the present invention, the chilled water coil as the cooling means for lowering the temperature of the return air flowing into the air washer device is provided on the inlet side (front stage). For this reason, the temperature of the return air sucked into the air washer device from a work room such as a clean room is lowered at the inlet, and the entire air washer device (spray chamber) is cooled, and the low-temperature return air is processed by each spray nozzle. ing. Therefore, it is possible to suppress the growth of bacteria on the spray nozzles 53a to 53c, the piping thereof, the inner wall surface of the air washer device (spray chamber) 50, and the like. Further, as compared with the case where the temperature of the return air sucked into the air washer device by only the cooling water is reduced, the amount of the cooling water used can be reduced by reusing the cooling water, so that the cost can be reduced.
[0029]
The air conditioning chamber 60 is provided with a circulation fan 61, a HEPA filter 62, and a hot water coil 63. These components are installed in a housing 64 of the air conditioning chamber 60. The return air cooled to a low temperature by passing through the air washer device 50 is reheated to a predetermined temperature by the hot water coil 63. The return air that has flowed into the air-conditioning chamber 60 passes through the HEPA filter 62, is cleaned, is heated to a clean room temperature condition by the hot water coil 63, and is supplied as a supply air to a work room such as a clean room.
[0030]
In the embodiment shown in FIG. 1 of the present invention, three heat exchangers are provided. 58a is a spray heat exchanger (first heat exchanger), 58b is a makeup water heat exchanger (second heat exchanger), and 58c is a hot water heat exchanger (third heat exchanger). Next, the operation of these heat exchangers will be described.
[0031]
The circulating water sucked by the first pump 56a from the first supply circulating water tank 55a passes through the first water treatment filter 57a for protecting the spray nozzle, and is located on the upstream side (inlet side) when viewed from the return air flow direction. Are supplied to the spray nozzles 53a and 53b. Make-up water (pure water) is supplied to the make-up water heat exchanger 58b through the pipe 80. The reason is that the temperature of the makeup water is 20 to 26 ° C., and the temperature of the makeup water is too high to be combined with the circulating water of the second makeup circulating water tank 55b whose temperature is 12 ° C. or less. It is. The make-up water is cooled to a low temperature by cold water by the make-up water heat exchanger 58b and supplied from the pipe 81 to the second make-up circulating water tank 55b.
[0032]
The circulating water sucked from the second replenishing circulating water tank 55b by the second pump 56b passes through a second water treatment filter 57b for protecting the spray nozzle and is supplied to the spray heat exchanger 58a. The circulating water is cooled to a low temperature by cold water by the spray heat exchanger 58a, and is supplied through the pipe 73 to the spray nozzle 53c on the downstream side (outlet side) as viewed from the flow direction of the return air. Thus, the low-temperature water from the spray heat exchanger 58a is supplied to the spray nozzle 53c provided on the outlet side of the air washer device.
[0033]
The cold water is supplied to the spray heat exchanger (first heat exchanger) 58a through the pipe 74. The cold water is supplied to a makeup water heat exchanger (second heat exchanger) 58b connected in series with the spray heat exchanger 58a by a pipe 75. Further, the cold water is supplied to a hot water heat exchanger (third heat exchanger) 58c connected in series with the makeup water heat exchanger by a pipe 76.
[0034]
The hot water heat exchanger 58c uses hot water used in the hot water coil 63 of the air conditioning chamber 60 to adjust the temperature of the cold water, which is higher than that of the cold water on the supply side, to a predetermined temperature. This cold water is supplied to the cold water coil 52 through the pipe 78. The cold water supplied to the cold water coil 52 returns to the supply side through the pipe 79.
[0035]
Here, in the present invention, an example of the temperature in each part of the air system and the water system obtained by the configuration of FIG. 1 will be described. The following temperature values are given as an example, and these temperature values are adjusted to appropriate temperatures depending on factors such as the installation environment of the apparatus and the season. The temperature of the return air (A) flowing into the air washer device 50 is 25 ° C., the temperature of the return air (B) after passing through the cold water coil 52 is 15 ° C., and the temperature of the return air (C) at the outlet of the air washer device 50 is 12 ° C. The temperature of the supply air (D) at the outlet of the air conditioning chamber 60 is 23 ° C.
[0036]
Next, the temperature of the makeup water (G) is 26 ° C., the temperature of the hot water (F) supplied to the hot water coil is 34 ° C., and the temperature of the returning hot water (F1) after passing through the hot water heat exchanger 58c is 22 ° C. .
The temperature of the cold water (E) on the supply side is 7 ° C., the temperature of the cold water (E1) passing through the pipe 75 after passing through the spray heat exchanger (first heat exchanger) 58a is 8.9 ° C., and the makeup water After passing through the heat exchanger (second heat exchanger) 58b, the temperature of the cold water (E2) passing through the pipe 76 is 10.9 ° C., and has passed through the hot water heat exchanger (third heat exchanger) 58c. The temperature of the chilled water (E3) supplied to the chilled water coil after passing through the pipe 78 is 12 ° C., and the temperature of the chilled water return (E4) returned to the chilled water supply unit through the dedicated chilled water return pipe 79 is 15 ° C. is there.
[0037]
The makeup water (G) is cooled to an appropriate temperature by the cold water (E) (G1) in the makeup water heat exchanger 58b as described above, and is supplied to the second makeup circulation water tank 55b. G1 is, for example, 9.9 ° C. These first, second, and third heat exchangers output cold water at a lower temperature as they are closer to the cold water (E) on the supply side. That is, the temperature of the cold water is set in the order of (E3)>(E2)> (E1). Therefore, the supplied cold water (E) gradually rises in temperature each time it passes through the first, second, and third heat exchangers.
[0038]
The spray heat exchanger (first heat exchanger) 58a controls the temperature of the cold water supplied to the spray nozzle 53c provided on the outlet side of the air washer device as described above to control the humidity of the processing air outlet. It is installed at the outlet side of the air washer device so that low-temperature cold water is supplied.
[0039]
The makeup water heat exchanger (second heat exchanger) 58b installed at the next stage of the spray heat exchanger 58a lowers the temperature of the supplied makeup water to flow into the second makeup circulation water tank 55b. For this reason, the energy required for cooling the makeup water is set at an intermediate level. Further, the temperature of the cold water is raised by returning the hot water used to reheat the air to the hot water heat exchanger (third heat exchanger) 58c that supplies the cooling water to the cold water coil 52. .
[0040]
Thus, in the embodiment of FIG. 1, the temperature difference between the cold water (E) on the supply side and the cold water return (E4) is large. Accordingly, the pipe diameter is reduced because the amount of cold water may be small. Further, since the cooling water supply power may be small, the cost required for the equipment can be reduced. When the temperature difference between the cold water (E) on the supply side and the cold water return (E4) is small, on the contrary, the amount of cold water increases and the pipe diameter increases. In addition, the power for supplying cold water increases.
[0041]
As shown in FIG. 1, in the present invention, as a heat exchanger, a spray heat exchanger (first heat exchanger) 58a, a makeup water heat exchanger (second heat exchanger) 58b, a hot water heat exchanger (Third heat exchanger) Three units 58c are connected in series by piping and installed. That is, the pipes between the heat exchangers are connected in a cascade manner. Therefore, compared to the case where a plurality of heat exchangers are installed in parallel, when installing the piping, the width dimension of the piping path can be narrowed, and the space can be saved.
[0042]
In the present invention, the energy required for cooling the return air in the air washer device 50 is arranged according to the required temperature, and the heat exchangers are arranged in series so that the cold water can be used from low to high in order of energy. The final destination of the cold water is supplied to a cooling coil provided on the upstream side of the air washer device 50 through a hot water heat exchanger (third heat exchanger) 58c.
[0043]
In the embodiment of the present invention, the inflow temperature of the return air into the air washer device 50 is 25 ° C., the temperature of the chilled water (E 3) supplied to the chilled water coil 52 is 12 ° C. Can be Further, by providing the cold water coil 52, it is possible to secure a required cooling amount for the return air to be processed. Further, since the first to third heat exchangers are connected in series through pipes, a cold water cascade utilization system is established in the configuration of the present invention, and a large temperature difference can be secured. it can. And the amount of water used in the pollutant removal device can be reduced to about half of the conventional amount.
[0044]
In addition, by lowering the temperature of the return air flowing into the air washer device 50 at the inlet, the temperature of the entire air washer device 50 (spray chamber) can be lowered, and the propagation of bacteria can be suppressed. Furthermore, since the HEPA filter is provided at the inlet of the air washer device 50 in addition to the above-described countermeasures against bacteria, the propagation of bacteria can be more effectively suppressed.
[0045]
In the embodiment of the present invention, the cooling coil is used as a dry coil. Then, for example, cold water of 12 ° C. is supplied to the cooling coil. By supplying water to such an extent that condensation does not occur in such a cooling coil, it is possible to prevent the deterioration of the fin and the generation of bacteria due to the condensation of the cooling coil. The temperature of the cold water supplied to the cold water coil can be determined as appropriate in consideration of the condensation of the coil and the like.
[0046]
【The invention's effect】
As is clear from the above description, according to the present invention, the following specific effects can be obtained. That is, it is possible to significantly reduce the amount of cold water used while ensuring sufficient contaminant removal capability. As described above, since the cost of piping and the heat source capacity can be reduced by reducing the amount of cold water used, the cost of the entire building in which the pollutant removal device is installed can be significantly reduced.
[0047]
In addition, with the reduction of water usage, it became possible to reduce the pipe diameter and the heat source equipment. Further, since the temperature of the return washer air washer device can be reduced, the growth of bacteria is suppressed. Therefore, maintenance (running) costs for removing bacteria can be reduced. In addition, saving cold water can contribute to global environmental improvement measures.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing a contaminant removal apparatus according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram of a conventional example.
[Explanation of symbols]
50: air washer device, 51: HEPA filter, 52: cold water coil, 53a to 53c: spray nozzle, 55: replenishing circulating water tank, 56a, 56b: pump, 57a, 57b ... water treatment filter, 58a ... spray heat exchanger, 58b ... makeup water heat exchanger, 58c ... hot water heat exchanger, 60 ... air conditioning chamber. 70, 71 ... water collecting pipe, 72-79 ... piping,

Claims (9)

A spray chamber having a plurality of rows of spray nozzles, a replenishing circulating water tank connected to the spray chamber and a water collecting pipe and supplied with make-up water, and the spray nozzle and the replenishing circulating water tank connected by piping, A contaminant removing device for removing contaminants in air flowing into a spray chamber by circulating water ejected from a spray nozzle, wherein a cooling means for lowering the temperature of the flowed air is provided in the spray chamber. A pollutant removal device. The contaminant removal apparatus according to claim 1, wherein a filter is provided before the cooling unit. The contaminant removal apparatus according to claim 1, wherein the cooling unit is configured by a chilled water coil, and the chilled water coil is provided on an inlet side of the spray chamber. A spray chamber having a plurality of rows of spray nozzles, a replenishing circulating water tank connected to the spray chamber and a water collecting pipe and supplied with make-up water, and the spray nozzle and the replenishing circulating water tank connected by piping, A contaminant removal device that removes contaminants in the air that has flowed into the spray chamber by circulating water ejected from the spray nozzle,
A first heat exchanger into which the circulating water from the make-up circulating water tank flows, and a second heat exchanger into which the make-up water flows, wherein the plurality of rows of spray nozzles from the first heat exchanger are provided. While supplying low-temperature circulating water to a part, low-temperature make-up water is supplied from the second heat exchanger to the make-up circulating water tank, and cold water is supplied to the first heat exchanger and the second heat exchanger. A contaminant removal device, which is connected in series by a flowing pipe. The contaminant removal apparatus according to claim 4, wherein a spray nozzle to which low-temperature circulating water is supplied from the first heat exchanger is provided on an outlet side of the spray chamber. The contaminant removal apparatus according to claim 4 or 5, wherein an air-conditioning room is installed on an outlet side of the spraying room, and cleanly temperature-controlled air is supplied from the air-conditioning room to a work room. . A third heat exchanger is provided outside the air conditioning room and connected in series by a pipe through which cold water flows with the second heat exchanger, and the third heat exchanger reheats air in the air conditioning room. Through the return water of the hot water used for the cooling, the cold water passing through the second heat exchanger is adjusted to a predetermined temperature, and supplied to the cooling coil installed in the spray chamber. The pollutant removing device according to any one of claims 4 to 6. Cold water is supplied to the first heat exchanger, the second heat exchanger connected in series with the first heat exchanger by piping, and the second heat exchanger in series with piping. The contaminant removal apparatus according to claim 7, wherein the cold water flows through the connected third heat exchanger. The temperature of the cold water supplied from each of the heat exchangers is such that the temperature of the cold water supplied from the first heat exchanger is the lowest and the temperature of the cold water supplied from the third heat exchanger is the highest. The contaminant removal device according to claim 7 or 8, wherein:

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