JPH0796126A - Air purifier - Google Patents

Abstract

PURPOSE:To obtain a sufficient purification degree (Na ion removal efficiency), even in the case large quantity of Na ions are contained in outdoor air at the time of typhoon, etc. CONSTITUTION:This purifier is constituted so that intake air A is successively passed through a wet type scrubber treating device 2 and a dry type filter device, and the wet type scrubber treating device 2 is constituted so that water is sprayed from the upper part to the introducing air to be treated, and the treated air is allowed to flow to the dry type filter device. The dry type filter device is arranged in order of a pre-filter 13, a middle performance filter 14 and an HEPA filter 15 from the inlet side to the outlet side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air cleaning apparatus whose object is effective in a factory or facility in a seaside area, especially in a semiconductor factory.

[0002]

2. Description of the Related Art Outside air introduced into a semiconductor factory, particularly a clean room for semiconductor production located in a coastal area, contains many ions in addition to Na ions contained in sea breeze, which greatly affects the yield of products.

For this reason, conventionally, as shown in FIG. 1, outside air has mainly been passed through a wet scrubber processing apparatus to mainly remove Na ions.

That is, outside air A is blown into the inside of the wet scrubber processing device 2 by the blower 1 from the lower side, and tap water or industrial water (hereinafter referred to as tap water) is sprayed from above by the spray 3 to obtain the outside air A and the water supply. In the process of passing the filling material 4 through water, the water was sufficiently contacted, Na ions were transferred to the tap water side, and after cleaning, the air was introduced into the clean room of the semiconductor factory as A '. Tap water is pump 5
It is being used in circulation.

[0005]

However, in the conventional equipment of this kind, although the efficiency of removing Na ions is relatively satisfactory under normal conditions, a large amount of Na ions are contained in the outside air such as during a typhoon. In some cases, the target Na ion removal efficiency cannot be obtained.

Therefore, an object of the present invention is to obtain sufficient Na ion removal efficiency even when a large amount of Na ions are contained in the outside air such as during a typhoon.

[0007]

SUMMARY OF THE INVENTION The above problem is that the introduced air flows through a wet scrubber treatment device and a dry filter device in that order, and the wet scrubber treatment device is installed above the introduced air to be treated. The structure is such that water is sprayed from and the treated air flows to the dry filter device. The dry filter device has a prefilter, a medium performance filter, and a HEPA filter arranged in order from the inlet side to the outlet side. Can be solved with.

In this case, the treatment water in the wet scrubber treatment device is pure water, and the introduced air is a main route guided to the dry filter device through the wet scrubber treatment device, and a direct route to bypass the main route. It is particularly preferable that a bypass path leading to the main path and the bypass path is provided so as to be selectable.

[0009]

In the present invention, Na ions that cannot be treated (removed) by the wet scrubber treatment device can be removed by the dry filter device, especially during a typhoon.

On the other hand, if only the dry filter device is used,
A large amount of ions adhere to the filter surface, the frequency of filter replacement increases, and the cost increases. Further, the target Na ion removal efficiency cannot be obtained during a typhoon. It is possible to install a wet scrubber treatment device after the dry filter device, but it is unavoidable that the filter replacement frequency increases.

The concentration of Na ions contained in the outside air is, for example, about 0.2 μg / m ³ during normal times and about 100 μg / m ³ during typhoons. On the other hand, according to the present invention, it is possible to perform cleaning to values much smaller than these values in normal times and during typhoons.

[0012]

The present invention will be described in more detail by way of examples with reference to the drawings.

The wet scrubber processing device 2 has a structure basically similar to that of the conventional example. External air A is blown into the wet scrubber processing device 2 from the lower part, and pure water is sprayed from the upper part by a spray 3 to obtain the external air. In the process of passing A and pure water through the filler 4, it is sufficiently brought into contact with each other to transfer Na ions to the pure water side for cleaning. A mist catcher 7 is provided at the exit of the wet scrubber processing device 2.

The air treated in the wet scrubber treatment device 2 is introduced into the dry filter device 10. The dry filter device 10 includes an eliminator 11, an electric heater 12, a prefilter 13, and a medium performance filter 1 in this order.
4. A HEPA filter 15 is provided. The treated purified air A ′ is, for example, the introduced air for a clean room of a semiconductor factory.

In a preferred embodiment of the present invention, pure water is used as the treated water used in the wet scrubber treatment apparatus 2 unlike the conventional example. In order to circulate and use this pure water, the treated water accumulated at the bottom is purified by the pump 5 through the cartridge polisher 21 and the precision wet filter 22, and then used for spraying. Also,
The pure water that has overflowed or evaporated in the wet scrubber 2 is supplied after the makeup water W is purified by the carbon cartridge filter 31, the cartridge deionizer 32, and the cartridge filter 33. Here, the cartridge deionizer 32
Instead of this, it is also possible to use a water purifying device using a reverse osmosis membrane.

On the other hand, except when there is an emergency such as during a typhoon, the dry filter device 10 alone can achieve a sufficient target Na ion removing property. Therefore, in the embodiment, as described above, the dry filter device 2 is used to dry the dry filter device. Device 1
A bypass path 40 is provided for the main path guided to 0 to bypass the main path and is directly guided to the dry filter device 10, and a path that passes through each of the main path and the bypass path 40 is set, for example, in the introduced air A. It is selectable based on a signal from a Na ion concentration meter (not shown) or an instruction signal from an operator indicating that it is a typhoon.

(Experimental Example) The effects of the present invention will be clarified by showing the experimental results of the present invention.

<Experiment 1> In the equipment shown in FIG. 1, salt water was added to the air to contain Na ions, and artificial sea breezes were produced and treated. In this experiment 1, the wet scrubber processing device was not passed, and the bypass 40
Was directly introduced into the dry filter device 10. Also, when the treatment efficiency was investigated by changing the amount of salt water added,
The results shown in FIG. 3 were obtained. The sampling points X, Y, Z in FIG. 3 are the positions shown in FIG.

As a result, when the Na ion concentration in the introduced air is low, the target purified air can be obtained by passing only the dry filter device, but the Na
It was found that when the ion concentration is high, that is, when the typhoon is strong, the Na ion concentration is considerably high.

<Experiment 2> The bypass 40 was closed, and instead, the wet scrubber device 2 and the dry filter device 10 were sequentially passed through for processing. In addition, Na in the introduced air
When the treatment efficiency was investigated by changing the ion concentration to 4 ways,
The results shown in FIG. 4 were obtained. The sampling point S is the position shown in FIG.

From this result, it was found that even if the Na ion concentration of the introduced air is high, the target outlet Na ion concentration can be made lower than the target.

On the other hand, the results indicated by the broken line are the results when tap water was used instead of pure water in the wet scrubber processing apparatus. According to this, at the outlet of the wet scrubber treatment device, the concentration of Na ions derived from tap water was increased, and the concentration of Na ions in the finally obtained purified air was considerably lowered, but on the contrary, It was also found that the concentration of Na ions in the initially introduced air was higher than that of the original introduced air, and that the stable processability was difficult.

[0023]

As described above, according to the present invention, even when a large amount of Na ions are contained in the outside air, such as during a typhoon,
A sufficient Na ion removal efficiency can be obtained.

[Brief description of drawings]

FIG. 1 is an overall view of an example of an air cleaning device of the present invention.

FIG. 2 is a schematic diagram of an example of a conventional air cleaning device.

FIG. 3 is a graph showing experimental results.

FIG. 4 is a graph showing experimental results.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Kenji Hiraoka 4-4-2 Nihonbashihonishicho, Chuo-ku, Tokyo Mitsui Second Annex Shin Nihon Air Conditioning Co., Ltd. (72) Osamu Yabuta Nihonbashimoto, Chuo-ku, Tokyo Ishinomaki 4-chome 4-20 Mitsui 2nd Annex Shin Nihon Air Conditioning Co., Ltd. (72) Inventor Takashi Okamoto 2-25-2 Kandasuda-cho, Chiyoda-ku, Tokyo Toshiba Air Conditioning Co., Ltd. (72) Inventor Yukihisa Yabe Tokyo 2-25-2 Kandasuda-cho, Kyoda-ku, Tokyo Inside Toshiba Air Conditioning Co., Ltd. (72) Inventor Masaaki Hattori 1-1-1 Shibaura, Minato-ku, Tokyo Inside Toshiba Head Office

Claims (2)

[Claims] 1. Introduced air is configured to flow through a wet scrubber processing device and a dry filter device in that order, and the wet scrubber processing device is treated by sprinkling water from above onto the air to be treated to be introduced. An air purifying device, characterized in that air flows to a dry filter device, and the dry filter device comprises a pre-filter, a medium-performance filter, and a HEPA filter arranged in order from the inlet side to the outlet side. 2. The treatment water in the wet scrubber treatment device is pure water, and the introduced air is guided directly to the dry filter device by bypassing the main route to the dry filter device through the wet scrubber treatment device. The air purification apparatus according to claim 1, wherein a bypass path is provided, and paths for passing the main path and the bypass path are selectable.