JPH10286428A - Air purifying device for purified space - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively remove vaporized chemicals by injecting the air of a space to be purified through an injection nozzle into a gas-liquid mixing cylinder, allowing the air to pass through a gas-liquid separation room and a purifying filter to be returned to the space to be purified, while discharging a cleaning liquid after the liquid is made to pass through the gas-liquid mixing cylinder. SOLUTION: The air in a clean room containing gaseous org. amines is jetted by a blower through a jetting nozzle 11 into a gas-liquid mixing cylinder body 9 and is made to flow upward while rotated by a static mixing vane 17a of a packing member 17. In this process, a cleaning liquid in a liquid tank is supplied under pressure by a liquid supply pump and is jetted through a spray nozzle 14 in the upper part of the gas-liquid mixing cylinder 4 and mixed with the air in the clean room 2. Thereby, the org. amine gas is dissolved and absorbed by the cleaning liquid and returned to the liquid tank. The air passing through the mixing vane 17a is separated from water drops in a gas-liquid separation room 5. The air is made to pass through a chemical filter 6 and an activated carbon filter 21 and returned to the clean room through the discharge port of an air passage 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for absorbing gas such as organic amine generated during work performed in a clean space such as a clean room or removing dust and the like to maintain ultra-cleanliness. .

[0002]

2. Description of the Related Art In post-processing of a wiring work in a semiconductor manufacturing process, an organic amine solution containing monoethanolamine or dimethylsulfoxylo as a main component is used as a stripping solution for a semiconductor resist. When the organic amine liquid evaporates and fills the clean room, there is a risk that defects are likely to occur in the pattern formation of the wafer, which may cause a defective product, and also a risk of adversely affecting the human body. In addition, in addition to the organic amine liquid, there is a case where it is necessary to use a chemical which may cause a problem in the production of a semiconductor or adversely affect a human body. For this reason, conventionally, for example, when a vertical laminar flow type clean room is adopted, primary and secondary chemical filters are provided in series in a room partitioned in a ceiling portion to allow air in the room to pass therethrough, and a HEPA filter. To maintain the ultra-cleanliness of the entire clean room.

[0003] As another method, a box connected to a loading / unloading entrance of the manufacturing apparatus is connected to a manufacturing apparatus installed in a clean room, and is used in an interface box for local cleaning for bringing processing materials into and out of the manufacturing apparatus. A processing material carry-in / out chamber is formed in the main body, and an opening / closing door is provided on a front surface of the box main body to allow the processing material to enter / exit the carry-in / out chamber. With a filter,
Further, there is disclosed a structure in which an exhaust system for exhausting ultra-clean air in the carry-in / out chamber to a clean room under-floor chamber is provided in a box body below the carry-in / out room to perform local cleaning. (Japanese Unexamined Patent Publication No. 08-088155)

[0004]

[Problem] In the first prior art, since a vaporized gas such as an organic amine spreads in a clean room and then passes through a chemical filter, it cannot be sufficiently cleaned. Further, in the second prior art, a chemical filter and a high-performance filter are provided in each work table (interface box), however, the organic amine gas is hardly adsorbed even by the chemical filter, and is generally used once (one time). Sheets) is not enough, and two sheets (secondary filters) are required. However, when such a device is provided with a secondary chemical filter, there is a problem that the equipment cost is high, and regular or irregular replacement is frequent, and the running cost is increased.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and separately from a chemical filter and an ULPA filter, a cleaning liquid and air to be cleaned are mixed and brought into contact with each other to achieve ultra-clean. It is an object of the present invention to provide an air purification device for a clean space that maintains a space and removes vaporized chemicals.

[0006]

SUMMARY OF THE INVENTION The gist of the present invention is to provide a tubular body having a closed lower end, at least in the vicinity of the lower end, a blowing nozzle for blowing air upward from a lower part, and a connecting pipe communicating between the inside and the outside of the cylindrical body. The gas-liquid mixing cylinder, the gas-liquid separation chamber, and the air purification filter are connected in the vertical direction, and the air in the space to be cleaned is blown out from the blast nozzle by the blower into the gas-liquid mixing cylinder. , A gas-liquid separation chamber, an air circulation circuit that passes through the purification filter in order and returns to the space to be cleaned, and a cleaning liquid is sent to the gas-liquid mixing cylinder by the liquid sending pump and then separated from the gas. A cleaning liquid circulation circuit that discharges and cleans the air, thereby adsorbing mixed chemicals and dust to the cleaning liquid to purify air in the space to be cleaned. . Hereinafter, this will be described in detail with reference to the drawings.

[0007]

Embodiment 1 FIG. 1 is a schematic view of an air purification device 1 for a clean space showing one embodiment of the present invention, and FIG. 2 is a sectional view specifically showing an embodiment of a gas-liquid mixing cylinder 4 of FIG. FIG. 3 is a sectional view showing another embodiment of the gas-liquid mixing cylinder 4.

[0008] The air purifying apparatus 1 according to the present invention is installed and used in a space such as a clean room where maintenance of a clean space is required for semiconductor manufacturing or the like. In the first embodiment of the present apparatus, there are roughly four components in the vertical direction, which are organically connected to achieve the object of the present invention. First, the lower stage is composed of the liquid tank 3, the middle stage is composed of the gas-liquid mixing cylinder 4, the gas-liquid separation chamber 5, and the upper stage is a chemical filter 6 acting as a purification filter.

In the lower liquid tank 3, a cleaning liquid 7 capable of adsorbing gas components floating in the space to be cleaned, for example, pure water in the present embodiment, is stored. A water supply pipe 8a is connected to an upper part of the tank 3, and a drain pipe 8b is connected to a lower part thereof. When a certain amount of the washing liquid 7 is maintained and the performance is reduced due to the dirt or adsorption capacity approaching a saturated state, The liquid can be replaced.

At the lower end of the gas-liquid mixing cylinder 4, a gas-liquid mixing cylinder main body 9 composed of a vertically long cylinder having a closed portion 10 is provided. A fume nozzle 11 that is open and injects air upwards;
A liquid connecting pipe 12 is provided on the wall or closed portion 10 of the gas-liquid mixing cylinder main body 9 below the nozzle opening of the blast nozzle 11. The fumarole nozzle 11 communicates with the inside of the clean room 2 via a blower 13 via a pipe.

At the upper end of the gas-liquid mixing cylinder body 9, a liquid feed pipe 15 having a spray nozzle 14 opening downward is connected to the inside of the tank 3 via a liquid feed pump 16.
Further, a gas-liquid separation chamber 5 composed of a space is formed above the spray nozzle 14 near the upper end of the gas-liquid mixing cylinder 4.

In the gas-liquid mixing cylinder 4, a filling member 17 is inserted into the mixing cylinder main body 9 in order to improve the gas-liquid contact efficiency. The filling member 17 is formed by providing a stationary mixing blade 17a for applying a swirling force to a fluid passing through the ring in a ring substantially equal to the inner diameter of the mixing cylinder body 9. When the filling members 17 are inserted into the mixing cylinder main body 9 and stacked upward, the filling members 17 having stationary mixing blades whose turning directions are opposite to each other are alternately stacked.

In the gas-liquid separation chamber 5, which is a space above the gas-liquid mixing cylinder 4, a baffle plate 18 for promoting gas-liquid separation is provided in a horizontal direction so as to block about half of the passage. An electric heater 19 for increasing the amount of saturated water and evaporating the remaining water to prevent clogging and shortening of the life of the filter 6 is provided in the flow path after passing through the gas-liquid separation chamber 5.

An adsorbent chamber 22 containing an adsorbent such as activated alumina, molecular sieve (trade name), or activated carbon is connected to the liquid connection pipe 12 opened at the lower end of the gas-liquid mixing cylinder main body 9 and collected. The amine and the like absorbed in the pure water 6 are removed by adsorption.

Further, the gas passage 2 above the gas-liquid separation chamber 16
Inside 0, a chemical filter 6 containing an activated carbon filter 21 is provided across the passage 20, and air is discharged from the air outlet into the clean room 2 after passing through the filters 6 and 21.

According to the present embodiment having the above-described structure, the air in the clean room 2 containing the vaporized organic amine in the clean room 2 is sucked by the blower 13 and passes through the air supply pipe from the blast nozzle 11 to the upper side. Toward the inside of the gas-liquid mixing cylinder body 9. The jetted air is directed upward by the stationary mixing blade 17a of the filling member 17 while trying to rotate in the forward and reverse directions. On the other hand, the cleaning liquid 7 in the liquid tank 3 that has been pressure-fed by the liquid feeding pump 16 is sprayed downward from the spray nozzle 14 in the upper part of the gas-liquid mixing cylinder 4 into a mist. The jetted liquid flows downward while rotating in the forward and reverse directions by the stationary mixing blade 17a, and is returned from the liquid connection pipe 12 into the liquid tank 3 to form a cleaning liquid circulation circuit. For this reason, the air in the clean room 2 and the cleaning liquid 7 that are jetted upward are mixed strongly and come into contact with each other.

Here, monoethanolamine and dimethylsulfoxylo, which are the main components of the organic amine, have the property of being soluble in water. Further, the cleaning liquid 6 of this embodiment uses pure water to further improve the performance. Thus, the organic amine gas is dissolved and absorbed in the cleaning liquid 7 in the gas-liquid mixing cylinder 4 and is returned to the liquid tank 3. As a result,
When the concentration of the organic amine was measured with the apparatus of this example,
What was 50 ppb at the time of the intake of the blower 13,
In the vicinity of passing through the gas-liquid mixing cylinder 4, the gas was purified to 5 ppb or less. Further, fine particles and bacteria in the air also adhere to the mist-like cleaning liquid 7, are collected, and returned to the lower tank 3 together with the cleaning liquid 7.

The air that has passed through the stationary mixing blade 17a of the gas-liquid mixing cylinder 4 has a larger cross-sectional area than the gas-liquid mixing cylinder body 9 and has a lower air flow rate, so that gas-liquid separation becomes easier. In the separation chamber 5, the water droplets that collide with the baffle plate 18 and are wound up are further separated.

Next, the air that has passed through the gas-liquid separation chamber 5 is
Heated by the electric heater 19, the amount of saturated steam increases. For this reason, the humidity is reduced and vaporization is promoted, so that water droplets do not adhere to the chemical filter 6 or the activated carbon filter 21. Components not captured by the gas-liquid mixing cylinder 4 are chemically adsorbed and removed by the filter 6, and purified air is returned to the clean room 2 from the outlet of the air passage 20. Thus, an air circulation circuit is formed. Here, when the concentration of the organic amine was measured near the outlet of the air passage 20, the concentration was lower than 5 ppb and decreased to a value having no problem. The cleaning solution 7 and the chemical filter 6
Is replaced according to the degree of contamination or periodically.

Next, a second embodiment of the present invention will be described with reference to FIG. In the present embodiment, there is no spray nozzle 14 in the first embodiment, and the liquid sending pipe 15 is connected to the liquid connecting pipe 12. A cleaning liquid recovery port 23 is provided at the bottom of the gas-liquid separation chamber 5 and is connected to the liquid tank 3 via an adsorbent chamber 22 (not shown).

In the second embodiment, an ejector action is generated by the force of the air to be cleaned which is jetted upward from the jet nozzle 11, and the vicinity of the jet nozzle 11 is brought into a vacuum state. Thereby, the cleaning liquid is sucked up from the liquid connection pipe 12, and
And / or the cleaning liquid is sent by the liquid sending pump 16.
The cleaning liquid rises together with the bubbles while being stirred in the gas-liquid mixing cylinder 4 in the same direction as the flow of the air. When the ejector action is strong and the cleaning liquid is sufficiently sucked into the gas-liquid mixing cylinder 4, the liquid supply pump 16 may not be provided.

As described above, when the cleaning liquid 7 and the air supplied into the gas-liquid mixing cylinder 4 are mixed with bubbles ejected from the blast nozzle 11 and rise, the organic amine and the like are dissolved and transferred to the cleaning liquid 7 side. The air that has passed upward through the gas-liquid mixing cylinder 4 is
After the cleaning liquid 7 is separated in the gas-liquid separation chamber 5, the cleaning liquid 7 is passed through the filter 6 (21) and returned to the space to be cleaned as in the first embodiment to form an air circulation circuit. On the other hand, 5
The cleaning liquid 7 separated by the above is recovered into the liquid tank 3 from the cleaning liquid recovery port 23 to form a cleaning liquid circulation circuit.

In the first and second embodiments, the liquid tank 3 is provided integrally. However, the liquid tank 3 may be provided separately without being integrated. Furthermore, without providing a liquid tank,
The supply side may be connected to a pure water production apparatus, and the drainage side may be connected to a pure water treatment apparatus, and the water may be flown. Further, in the embodiment, an example of installation in a clean room was given, but the invention is not limited to this, and installation in a clean booth or the like if the structure is aimed at a clean space is also included in the scope of the present invention. It is. In addition, it can be installed in a ceiling passage, underfloor passage, etc. even in a clean room, or it can be installed outside the clean room in communication with the clean room.

[0024]

As described above, the air purifying apparatus according to the present invention can remove gas such as organic amine generated in a clean space by reducing the number of chemical filters used, thereby reducing equipment costs and running costs. Furthermore, since the removal of dust and the like from the clean air is simultaneously performed by the present apparatus, purification is promoted, and the HEPA filter and the like can be made simpler. Further, since it is relatively small and can be easily installed, there is an effect that it can be sequentially installed and used at necessary places inside and outside the clean room.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an embodiment of the present invention.

FIG. 2 is a sectional view specifically showing an embodiment of the gas-liquid mixing cylinder 4 of FIG.

FIG. 3 is a sectional view showing a second embodiment of the gas-liquid mixing cylinder of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air purification apparatus 2 Clean room 3 Liquid tank 4 Gas-liquid mixing cylinder 5 Gas-liquid separation chamber 6 Chemical filter 7 Cleaning liquid 8 Water supply / drain pipe 9 Gas-liquid mixing cylinder main body 11 Spray nozzle 13 Blower 14 Spray nozzle 16 Liquid pump 17 Filling member 18 Plate 19 Electric heater 22 Adsorbent room

Claims (9)

[Claims] 1. A gas-liquid mixing cylinder comprising a tubular body having a closed lower end and having a fumarolic nozzle at least near the lower end for ejecting air upward from a lower part and a connecting pipe communicating between the inside and the outside of the cylindrical body. , A gas-liquid separation chamber and an air purification filter are connected in a vertical direction, and air in the space to be cleaned is blown out from a fumarolic nozzle into a gas-liquid mixing cylinder by a blower. An air circulation circuit that passes through a purifying filter in order and returns to the space to be cleaned, and a cleaning liquid that is sent to a gas-liquid mixing cylinder by a liquid sending pump and then passed therethrough and then separated and discharged from gas. An air purification device for a clean space, comprising a circulation circuit to adsorb mixed chemicals and dust to a cleaning liquid to purify air in a space to be cleaned. 2. A gas tank comprising: a liquid tank; a cylinder closed at a lower end, and a fumarolic nozzle at least in the vicinity of the lower end for ejecting air upward from a lower portion, and a connection pipe communicating between the inside and the outside of the cylinder. A liquid mixing cylinder, a gas-liquid separation chamber, and an air purification filter are vertically connected to each other, and air in the space to be cleaned is blown out from a blowing nozzle into the gas-liquid mixing cylinder by a blower. An air circulation circuit that passes through the liquid separation chamber and the purification filter in order and returns to the space to be cleaned, and the cleaning liquid in the liquid tank is separated from the gas after passing through the gas-liquid mixing cylinder and then separated in the liquid tank. A cleaning liquid circulation circuit for recovering the cleaning liquid, thereby adsorbing mixed chemicals and dust to the cleaning liquid to purify air in the space to be cleaned. 3. A spray nozzle connected to a liquid feed pump is provided above the gas-liquid mixing cylinder to spray the cleaning liquid onto the upper part of the gas-liquid mixing cylinder, and the cleaning liquid is passed through the gas-liquid mixing cylinder from above to below. 3. The air purifying apparatus for a clean space according to claim 1, wherein a cleaning liquid circulation circuit recovers the cleaning liquid from a cleaning liquid recovery pipe opened at a lower end of the mixing cylinder. 4. A cleaning liquid recovery pipe that flows into the gas-liquid mixing cylinder at the lower end of the gas-liquid mixing cylinder connected to the liquid feed pump, passes through the gas-liquid mixing cylinder from below to above, and then opens at the lower end of the gas-liquid separation chamber. 3. The air purifying apparatus for a clean space according to claim 1, wherein the air purifying apparatus comprises a cleaning liquid circulation circuit for recovering the air from the cleaning space. 5. The method according to claim 1, wherein an adsorbent chamber containing an adsorbent is provided downstream of the washing liquid recovery pipe to adsorb and remove chemicals mixed in the washing liquid. An air purification device for a clean space as described in the above. 6. The air purifying apparatus for a clean space according to claim 1, wherein a baffle plate is provided in the gas-liquid separation chamber. 7. The air purifying apparatus for a clean space according to claim 1, wherein an electric heater is provided in the gas-liquid separation chamber. 8. The clean space according to claim 1, wherein a filling member provided with a stationary mixing blade for imparting swirling properties to the passing fluid is filled in the gas-liquid mixing cylinder. Air purification equipment. 9. The air purifying apparatus for a clean space according to claim 1, wherein pure water is used as the cleaning liquid.