JP5787136B2 - Air purification device - Google Patents

Description

  The present invention relates to an air purification device for purifying indoor air for a clean room.

  As this type of air purifying apparatus, as shown in Patent Document 1, for example, an apparatus having a configuration in which organic substances in a clean room are removed by a multistage water spray system and the cleaned air is returned to the clean room.

Japanese Patent No. 3941029

The above conventional air purification device is
・ Liquid gas ratio (ratio of required amount of purified water to the amount of air to be treated) is large, for example, about 3-4L / m ³ , and energy consumption required for pump power is large for circulating a large amount of purified water.
・ Even though the liquid gas ratio is large, the removal efficiency is not always good.
・ When organic substances in the air are removed with water, the growth of microorganisms is significant and maintenance costs increase.
-As a countermeasure against microorganisms, a water filter is installed in the piping path, a germicidal lamp is required in the circulating water tank, and the removal device becomes complicated and expensive.
There is a problem.

  In view of the above circumstances, an object of the present invention is to provide an effective and appropriate air purifying device capable of obtaining an excellent purifying effect while reducing initial cost and running cost.

The invention according to claim 1 is an air purifying apparatus for purifying indoor air for a clean room, a packed tower for introducing the air to be treated from the lower part and leading out from the upper part, and the packed tower is filled with the air. A hydrophilic filler capable of passing as an upward flow while being in contact with the air to be treated and capable of retaining purified water, and spraying purified water from above the filler to retain the purified water in the filler. Purified water comprising a purified water supply mechanism, wherein the filler retains contaminants in the treatment target air by passing the treatment target air in contact with the filler while passing through the packed tower. The filler is composed of a fabric formed by heat-sealing a cloth material and a mesh material, and a spacer formed by forming the mesh material into a corrugated shape alternately. Layered Wherein the molding fabric and the spacer is in a state of being a vertical posture is disposed in the packed tower, a waveform which is formed on the spacer is characterized in that there is a horizontal transverse waves.

According to a second aspect of the invention, an air purification device according to claim 1, wherein the purified water supply mechanism is characterized by being configured to be capable of supplying purified water containing ozone water.

The air purification apparatus of the present invention is a purification in which the filler retains the pollutant by allowing purified water to be retained in the packing material packed in the packed tower and passing the treatment target air in contact with the packing material. Since it is removed by dissolving in water, it has a simple structure compared to conventional water spray type purification devices, as well as excellent purification performance, and a small amount of purified water is simply added to the filler. Since spraying is sufficient, the amount of water required for the purified water can be remarkably reduced, and the pump power for that purpose can be greatly reduced. Therefore, the initial cost and running cost can be sufficiently reduced.
In particular, by allowing ozone water to be added to the purified water, it is possible to effectively prevent the growth of microorganisms.

It is a figure which shows the outline | summary of the air purification apparatus which is embodiment of this invention, and the whole air conditioning equipment provided with the same. It is a figure which shows the outline | summary of the filler in an air purifier. It is a figure which shows the effect by the Example of an air purifier. It is a figure which shows the effect by the Example of an air purifier.

An embodiment of an air purification device of the present invention will be described with reference to FIGS.
FIG. 1 shows an overall schematic configuration of an air conditioning equipment 1 provided with an air purification device 10 of the present invention. This air-conditioning equipment 1 is intended for a clean room. As shown in FIG. 1, the air-conditioning equipment 1 includes a primary air-conditioner 2 and a secondary air-conditioner 5 at the front and rear stages of the air purification apparatus 10 according to the present embodiment, and is air to be processed. The return air RA from the clean room is passed through the HEPA filter 3 in the primary air conditioner 2 to remove microbial particles, and is cooled to the dew point temperature through the cooling coil 4 and then introduced into the air purification device 10 of the present embodiment. After removing the pollutant, the air purified by passing through it is blown by the fan 6 provided in the secondary air conditioner 5 and passed through the HEPA filter 7 and adjusted to the desired temperature by the heating coil 8 as necessary. Basically, the supply air SA is circulated back to the clean room.

The air purification apparatus 10 of the present embodiment provided in the air conditioning facility 1 includes a packed tower 11 that introduces return air RA as processing target air from the lower part and leads out from the upper part as an upward flow, The filler 12 having hydrophilicity that can be passed while being in contact with the air to be treated and can retain purified water, and spraying purified water from above the filler 12 to cause the filler 12 to retain purified water. And a purified water supply mechanism 20.
In the packed tower 11 shown in the figure, a rectifying plate 30 is installed at the bottom and an eliminator 31 is installed at the top. A drainage tank 32 is provided below the packed tower 11 for receiving and recovering purified water flowing down or dripping from the packing material 12.

  As the filler 12 used in the air purifying apparatus 10 of the present embodiment, as shown in FIG. 2A, a molding formed by integrally heat-bonding a cloth material 13a made of polyester and a mesh material 13b made of polypropylene. The fabric 13 and the spacers 14 formed by molding a mesh material made of polypropylene into a corrugated shape are alternately laminated, and the air to be treated can pass through without any problem with low pressure loss while being in sufficient contact. is there.

As the cloth material 13a made of the above polyester, a polyester having a high hydrophilicity by increasing the number of yarn twists, making the cloth weave a satin texture, reducing the amount of dissolution in the cloth finishing process, and increasing the porosity. A cloth can be suitably employed.
Similarly, it is possible to use a cotton material as a cloth material having excellent hydrophilicity. However, the filler used in the present embodiment needs not only hydrophilic property but also durability against ozone. Is not suitable, and a polyester cloth is optimal as described above.

And in this embodiment, as shown to Fig.2 (a), both said shaping | molding cloth 13 and said spacer 14 are made into the vertical attitude | position, and the waveform currently formed in the spacer 14 was made into the horizontal transverse wave 14a. In a state (that is, in a state where the waveform is formed in the horizontal and horizontal directions), they are alternately stacked and stored in a rectangular cylindrical storage container 15 having a holding mesh 15a at the bottom as shown in (b). 1 unit of the packing material 12 in which the molding cloth 13 and the spacer 14 are laminated in multiple layers is configured, and the packing material 11 is mounted in a replaceable state in the packed tower 11.
The waveform formed in the spacer 14 may be formed as a vertical longitudinal wave. In this case, the air to be treated flows upward as it is along the longitudinal wave, which is advantageous in terms of pressure loss. Thus, it is advantageous to form the waveform as a transverse wave 14a in terms of water retention capacity of the purified water, and a larger contact area of the filler 12 with the air to be treated can be ensured. The waveform is preferably the transverse wave 14a.

  On the other hand, the purified water supply mechanism 20 includes a heat exchanger 21, a water supply pump 22, an ozone water generator 23, and a spray nozzle 24, and is cooled by the heat exchanger 21 to the dew point temperature of the processing target air. Purified water containing ozone water is supplied by passing purified water through the ozone generator 23 by the feed water pump 22 and supplying the purified water to which the ozone water has been added to the spray nozzle 24 through the feed water line 25 and spraying from above the filler 12. Water is retained in the filler 12.

In addition, as the above-described ozone generator 23, a system that generates ozone by directly electrolyzing purified water can be suitably employed, but a system that converts atmospheric oxygen into ozone and dissolves it in purified water. Can also be adopted.
Moreover, the ozone concentration in the purified water supplied to the packed tower 11 may be a low concentration of about 1.5 to 5 ppm, for example, and ozone water is not always added continuously to the purified water, but is added intermittently or intermittently. In any case, it is preferable that the amount of ozone water added and its concentration be adjustable. For this purpose, the ozone water generator 23 is provided with a bypass pipe 26 and an electromagnetic valve 27 for opening and closing the ozone water generator 23 as shown in the figure, and the ozone water generator 23 is operated intermittently or intermittently to produce purified water. It is preferable that the amount of ozone water added and the concentration thereof be adjusted optimally. Alternatively, an ozone water tank for storing ozone water may be separately provided, and the amount and concentration of ozone water may be adjusted by appropriately supplying ozone water to the purified water therefrom. .

When the air to be treated passes through the filler 12 as an upward flow in the packed tower 11, the air purification apparatus 10 having the above configuration naturally has the contaminants in the air to be treated held in the purified water retained in the filler 12. By contacting, the pollutant is dissolved and removed in the purified water, so that the air to be treated is purified.
That is, the return air RA from the clean room, which is the air to be treated, is introduced from the primary air conditioner 2 to the lower portion of the packed tower 11, rectified by the rectifying plate 30 and flows upward as a uniform flow, and flows upward. At that time, the purified water is retained and in contact with the surface of the filler 12 which is a wet surface, pollutants (especially organic substances) dissolve in the purified water, thereby purifying the air to be treated. Is done.
Fine air droplets are removed from the purified air by the eliminator 31, and the purified air is led out from the upper part of the packed tower 11, and circulates to the clean room by the secondary air conditioner 5.
On the other hand, the purified water sprayed on the filler 12 gradually flows down or drops while being retained in the filler 12, and countercurrently contacts with the air to be treated to dissolve the contaminants as described above. The purified water in which the substance is dissolved is finally collected from the lower part of the packed tower 11 into the drainage tank 32, appropriately treated and drained.

  According to the air purification device 10 of the present embodiment, the processing target air is brought into contact with the purified water retained in the filler 12 and the contaminants are dissolved and removed in the purified water. Only by spraying the purified water to retain the water, an excellent purification effect can be obtained as demonstrated in the following examples.

Example 1
Laminated fabric 13a made of polyester having a satin texture and mesh material 13b made of 20 mesh polypropylene are heat-sealed, and spacer 14 having a transverse wave 14a formed on a mesh material made of 10 mesh polypropylene. The filler 12 made is used. The cross-sectional size of the filler 12 was 294 mm × 294 mm, and its length (height) was four types of 300 mm, 600 mm, 900 mm, and 1200 mm.
The amount of air to be treated was 7.9 m ³ / min, the amount of purified water sprayed was 0.62 L / min (liquid / gas ratio was about 0.08 L / m ³ ), and the passing air speed in the packed tower 11 was 1.5 m / s.

FIG. 3 shows the relationship between the removal performance and the drain temperature when the pollutant to be purified is an organic solvent PGMEA (propylene glycol monomethyl ether acetate) component in the air. The straight lines in the figure are regression lines when the length of the filler 12 is 300 mm, 900 mm, and 1200 mm.
In this example, when the drain temperature was 13.5 ° C., a removal rate of 80% was obtained at a filler length of 900 mm, and a removal rate of 85% was obtained at a filler length of 1200 mm. In addition, a removal rate of about 70% was obtained when the filler length was 600 mm, and about 60% even when the length was 300 mm.
Since it is known that the Henry's constant in the vapor-liquid equilibrium of the organic solvent becomes smaller as the absorbing liquid temperature is lower, the removal rate of the measurement result according to this example depends on the drain temperature and is consistent with the absorption theory. It was confirmed that

  As a comparative example with respect to Example 1 above, a unit of the same size of 294 mm × 294 mm and a length of 900 mm is filled with a general-purpose ball-shaped filler (φ27 mm) used in a general packed tower, under the same conditions. When treated, the removal rate was only about 35%, and it was confirmed that the removal performance of the air removal device of the present invention was remarkably excellent.

(Example 2)
In the air purifying apparatus 10 shown in FIG. 1, the filler 12 is the same as that of the first embodiment, and eight units each having a cross-sectional size of 300 mm × 300 mm and a length of 900 mm are installed. The removal rate of PGMEA components at a drain temperature of 10 ° C with 65.9m ³ / min, purified water spray rate of 6.2L / min (liquid / gas ratio is about 0.09L / m ³ ), and the tower wind speed is 1.5m / s The removal rate was 90%, and a remarkably superior removal rate was obtained as compared with the case of the conventional filler as in Example 1.

(Example 3)
In the air purifying apparatus 10 shown in FIG. 1, the filler 12 is the same as that of the second embodiment, the air treatment amount containing PGMEA is 57.3 m ³ / min, the amount of purified water sprayed is 8 L / min (the liquid gas ratio is about 0.14). L / m ³ ), when the wind speed in the tower is 1.3 m / s, and ozone water is intermittently sprayed using the ozone water generator 23 (including purified water containing 1.5 ppm of ozone water and ozone water) No clarified water was sprayed every 12 hours alternately), and the microbial concentration in the drain was continuously measured.
As a result, as shown in FIG. 4, both the bacterial concentration and the fungal concentration were 100 cfu / mL or less over 400 days. When the filler was observed after 400 days, the filler was clean and did not show any microbial adhesion. From this, it was confirmed that microbial growth could be prevented by intermittently spraying ozone water with a concentration of 1.5 ppm.

  As described above, the air purification apparatus of the present invention allows the air to be treated to simply pass through the packed tower 11 as an upward flow, as well as obtaining a purification performance that is significantly superior to conventional purification apparatuses. In addition, since it has a simple configuration in which a small amount of purified water is sprayed onto the packing material 12 in the packed tower 11 to retain the water, the configuration is much simpler than a conventional water spray type purification device. Therefore, the initial cost can be reduced.

In particular, the air purification device of the present invention can greatly reduce the amount of water required for purified water compared to conventional multi-stage water spray type purification devices, and thus can efficiently operate, and thus can sufficiently reduce running costs. Is.
That is, the conventional multistage water spray type purification device obtains a purification effect by directly spraying a large amount of purified water onto the air to be treated, so that not only a large amount of purified water is required. While a large amount of pump power is required to circulate and use a large amount of purified water, the air purification device of the present invention allows the air to be treated to pass through the filler 12 in which the purified water is retained. Therefore, it is sufficient to spray a small amount of purified water as makeup water on the filler 12 by a one-pass method without circulating and using a large amount of purified water.
Therefore, the obtained significantly reduces the required amount of purified water according to the present invention, the liquid-to-gas ratio from a conventional 3~4L / m ³ approximately 0.08L / m ³ degree and conventional, as described above in Example It can be greatly reduced to about 1/30, and the pump power for that is also little, so the running cost can be reduced sufficiently.

  In addition, as in the above embodiment, the purified water supply mechanism 20 includes the ozone water generator 23 so that ozone water can be added to the purified water, thereby effectively preventing the growth of microorganisms. 10 can be continuously operated over a long period of time, so that the maintenance cost can be reduced in this respect as well, and it is extremely effective as an air purifying apparatus applied to a clean room requiring a high degree of cleanliness.

  Although the embodiment of the present invention has been described above, the above embodiment is merely a preferred example, and the present invention is not limited to the above embodiment, and may be appropriately selected within the scope of the present invention. Design changes and applications are possible.

  For example, the specific configuration of each part, such as the configuration and size of the packed tower 11 that is a component of the air purification device 10, the specific specifications of the packing material 12 filled therein, the configuration of the purified water supply mechanism 20, etc. The optimum design may be performed so that the optimum treatment can be performed in consideration of the types of contaminants to be removed, the degree of contamination, the required cleanliness, the amount of treatment air flow, and other conditions.

In particular, the purified water supply mechanism 20 only needs to be capable of spraying the minimum amount of purified water onto the filler 12 and retaining the purified water. Can be designed.
The purified water supply mechanism 20 is preferably provided with an ozone water generator 23 as in the above embodiment, so that it is possible to effectively prevent the growth of microorganisms. If the ozone water generator 23 is not necessary, for example, in the case where the breeding of the water is not expected, it may be omitted.

Moreover, although it is realistic to incorporate and use the air purification apparatus of this invention in the air-conditioning equipment 1 which makes a clean room the object like the said embodiment, it does not necessarily do so and the circulation means of the process target air is used. If prepared separately, the air purifier of the present invention can be used alone.
Of course, even when the air purification apparatus of the present invention is incorporated in the air conditioning equipment as described above, the configuration of the entire air conditioning equipment is arbitrary as long as the air to be treated is circulated through the air purification apparatus of the present invention. It is.

DESCRIPTION OF SYMBOLS 1 Air conditioning equipment 2 Primary air conditioner 3 HEPA filter 4 Cooling coil 5 Secondary air conditioner 6 Fan 7 HEPA filter 8 Heating coil 10 Air purifier 11 Packing tower 12 Filling material 13 Molding cloth 13a Cloth material (polyester)
13b Mesh material (polypropylene)
14 Spacer (Polypropylene)
14a Shear wave 15 Storage container 15a Holding mesh 20 Purified water supply mechanism 21 Heat exchanger 22 Water supply pump 23 Ozone water generator 24 Spray nozzle 25 Water supply line 26 Bypass line 27 Solenoid valve 30 Current plate 31 Eliminator 32 Drainage tank

Claims (2)

An air purification device for purifying indoor air for a clean room,
A packed tower for introducing the air to be treated from the bottom and leading from the top;
A filler having a hydrophilic property that is packed in the packed tower and can be passed as an upward flow while being in contact with the air to be treated and that can retain purified water; and
Comprising a purified water supply mechanism for spraying purified water from above the filler to retain the purified water in the filler;
A configuration for purifying the processing target air by allowing the processing target air to pass through the packed tower while being in contact with the packing material, thereby dissolving the pollutants in the processing target air in the purified water retained by the packing material. and,
The filler is formed by alternately stacking a molded cloth formed by heat-sealing a cloth material and a mesh material and a spacer formed by forming a mesh material into a corrugated shape, and the molded cloth and the spacer are vertically arranged. Arranged in the packed tower in a state of being in a posture,
An air purifier characterized in that a waveform formed on the spacer is a horizontal transverse wave . The air purification device according to claim 1 ,
The purified water supply mechanism is configured to be able to supply purified water including ozone water.

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