JPH0376993B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention is applicable to LSI, ultra-LSI manufacturing plants, biological drug manufacturing plants, operating rooms, precision machinery washing plants, sterile food manufacturing plants, articles placed there, and even clothes. It relates to methods of cleaning workers, sick people, etc.

More specifically, a mist of substantially less than 0.5 microns per cubic foot is applied to ultra-LSI manufacturing plants, sterile food manufacturing plants, air shower rooms where pre-work workers of these plants are located, and hospital rooms where seriously ill patients are located. This relates to a method of cleaning an object by sending air containing more than 50,000 particles.

Generally, hospitals, drug manufacturing factories, food manufacturing factories,
Research laboratories, laboratories, etc. require clean gas that does not contain dust or microorganisms, and for this purpose, measures such as supplying purified air using air filters or installing air curtains at entrances and exits are recommended. It is taken. However, with this method, it is not possible to obtain sufficiently purified gas,
Even if an air shower room is used, the purpose cannot be fully achieved.

The inventor conducted intensive research on cleaning objects, and found that the smaller the water droplet, the weaker the surface tension, and that when the water droplet becomes a mist of 0.5 microns or less, it strongly adheres to a minute object.
If a gas containing more than 50,000 particles per cubic foot is applied to an object, it will remove not only fine dust particles, but also bacteria, fungi, spores, and even viruses, and remove them, cleaning them. I learned that it is possible to transform In a gaseous atmosphere in which such fine water droplets are suspended, it is not only possible to clean the atmosphere, but also, quite unexpectedly, despite the presence of water droplets, it is possible to actually clean the atmosphere.
It has been found that no matter how large the number of mist particles is, as long as the size is 0.5 microns or less, the phenomenon of wetting objects does not occur, which is a remarkable effect.
As a result of further investigation, we found that when ordinary gas was passed through a gas atmosphere containing suspended fine water droplets, the ordinary gas was highly purified to an ultra-clean state. We also discovered that it can be applied directly to rooms, departments, and other relevant locations. Based on these new findings, we also conducted various experiments on a particularly industrially effective method for producing this microscopic water droplet suspended gas.
As a result of repeated research, the present invention has been completed.

That is, the present invention is a method for cleaning an object, characterized in that the object is treated with a gas in which a large amount of mist of substantially 0.5 microns or less is suspended.

The air in which a large amount of mist of substantially 0.5 microns or less is suspended for use in the present invention can be produced, for example, by the following process.
Of course, if an inert gas is required, nitrogen gas may be used instead of air.

Please refer to FIG. 1 first. This device is the most basic one, and a large number of water injection nozzles 2 are provided on the side of a tank 1. These nozzles 2 are
It is preferable that the positions of the nozzles provided on the opposing sides are slightly shifted and arranged alternately so that the opposing nozzles are not arranged on a straight line. The water injected from the water injection nozzle 2 crosses the tank 1 according to the dotted line D and collides with the opposing side surface to form fine water droplets E, and the inside of the tank 1 is filled with these fine water droplets.
Therefore, when gas is supplied from the bottom of the tank 1 in the direction of arrow A, as it rises in the tank 1, the gas contains sufficient fine water droplets and is discharged from the upper tank outlet, causing the mist to float. The desired gas can be obtained. If necessary, one or more baffle plates (not shown) may be installed vertically or at an angle (in series, in parallel, or alternately) in the tank 1, and the jet water flow can be directed to these baffle plates. may be caused to collide with each other to generate fine water droplets.

FIGS. 2 and 3 show an apparatus for producing mist floating gas more efficiently and with controlled temperature.

Here, we will explain the case of producing cooled mist floating gas as an example, but if the cooling-related system described below is replaced with a heated system, heated mist floating gas can also be freely produced.

The cyclone 40 has an air inlet 42 tangentially provided in the upper part of the cylindrical part 41 thereof. An outlet pipe 43 is provided in the center of the cylindrical portion 41 extending downward from above, and a cold water injection pipe 44 is disposed coaxially with the outlet pipe 43 to surround the outlet pipe 43. The injection pipe 44 is provided with a large number of injection nozzles 45 . Inside the cylindrical part 41 of the cyclone 40,
An evaporation pipe 47 of the refrigeration device is arranged. The positional relationship between the evaporation pipe 47 and the injection nozzle 45 may be completely shifted from each other, or may be slightly shifted from each other.
It is arranged so that it can be sprayed in a spray or jet state perpendicularly to the air. Cyclone cone 5
1, a filtration device 48, a water tank 49,
Pumps 50 are provided in sequence. Therefore, the cold water flows in the direction of arrow B, that is, the pump 50, the circulation pipe 46, the injection pipe 44, the cylindrical part 41 of the cyclone,
The water is circulated in the order of conical part 51, filtration device 48, water tank 49, and pump 50. A refrigerant, in particular a high temperature refrigerant (1°C to -5°C), circulates within the evaporator tube 47 in the direction of arrow C. The gas is fed into the cyclone through the inlet 42 in the direction of arrow A, contains fine water droplets in the cyclone, and at the same time is cooled to become the desired gas through the outlet pipe 43 to be used for the respective purpose. be done. (D) The water injected or sprayed from the injection nozzle 45 provided in the injection pipe 44 is transferred to the evaporation pipe 47 and/or the cylindrical part 4 of the refrigeration device.
When the water droplets collide with the side wall of 1 (E), a mist is generated (at the same time, the water flow that collided with the evaporator tube 47 exchanges heat with the refrigerant passing through the tube 47 and is cooled), and the water droplets are cooled. Ru. When gas is passed through such an atmosphere in the direction of arrow A,
This gas contains fine water droplets and exchanges heat with the cooled water droplets to cool itself and become the desired gas.

FIG. 4 is a schematic diagram showing a total system for actually applying the method of the present invention to a 64 kilobit RAM mass production factory. The mist floating gas produced in the cyclone 40 as described above is transferred to the drip removal cyclone 5 according to arrow A.
sent to 0. That is, the gas coming out of the drip-removing cyclone 50 enters the inside of the cyclone through an inlet provided in the tangential direction on the side wall of the cyclone 50, and while circulating inside the cyclone, excess water droplets and large water droplets are removed to a size of 0.5μ. A gas containing at least 90% of the following mist is prepared and taken out from an outlet pipe provided at the center of the cyclone 50.

The mist floating gas taken out in this way passes through the pipe P to the air shower room 60.
and then to the adjacent ultra-clean room 7.
Clean up the people working at 0. Further, a part of the mist floating gas is directly sent to the ultra-clean room 70, where the purified gas containing no dust is introduced into the room and is also used for cleaning the silicon plates used in the LSI. Also, if necessary, instead of directly using the mist suspended gas, normal air may be blown into a shower of this gas to be purified, and the thus purified air may be used. The gas used in the ultra-clean room 70 is taken out from there and returned to the cyclone 40 via the pipe P and fan F, and this cycle is repeated. According to this method, it was found that the ultra-clean room was maintained in an ultra-clean state with less than one particle of dust larger than 0.5 μ per 1 foot ³ space. Incidentally, tens of thousands of pieces of dust are floating in a typical factory, and this fact should show how superior the method according to the present invention is.

In addition, a heat exchanger 100 shown next to the drip removing cyclone 50 shown in FIGS. 5 and 6 is provided, and by passing the mist floating gas through this, the gas is raised to an optimal temperature and the mist is further improved. It is something that can be made small and increase its effectiveness. Heat exchanger 100 will now be described. That is, an air exhaust pipe 105 is vertically provided in the center of the can body 101 and communicates with an air conduit 105' provided outside the can body 101. Therefore, the air intake pipe 104
The air reaches the lower part while swirling inside the can body 101, rises from the lower part of the air discharge pipe 105, and moves in the direction of the arrow. Further, an outer pipe 106 and an inner pipe 107 are provided inside the pipe body 101, and the lower end of each pipe 106, 107 communicates with a pump 108 provided outside the can body 101, allowing hot or cold water to flow through the upper drain port. Water is drained from 109 and 110. There are washing water pipes 1 at the upper and lower parts of the pipe 101.
A large number of 11 water spouts 111a, 111b... are provided, which are directed above or below the upper and lower rows of pipes 106 and 107, toward the inner surface of the pipes 106 and 107, the inner surface of the can body 101, and the outer surface of the air discharge pipe 105. It is designed so that cleaning water can be squirted out. Further, a drain pipe 112' is provided below the cone portion 102, so that washing water in the can or drain caused by gas cooling can be drained away. Therefore, the air from the air intake port 104 separates dust etc. within the can 101 by the cyclone effect, and then flows through the pipes 106 and 10.
7, the air is heated or cooled to an appropriate temperature and is sent out from an air exhaust pipe 105. In addition, the separated waste is passed through the washing water pipe 111, and the water is passed through the nozzle 1.
11a, 111b... can be washed away by spraying water from them.

The gas treated in this way is almost completely suspended in a large amount of mist of 0.5 microns or less, so by treating objects with this, it is possible to clean all kinds of things. .

In the present invention, air is generally used as the gas, but if oxidation is not desirable, carbon dioxide, nitrogen gas, and other rare gases can also be used.
Conversely, oxygen gas can also be used, and various gases or mixtures thereof can be used freely and appropriately.

The surface tension of the mist of 0.5 microns or less used in the method of the present invention is extremely low, and it easily attaches to objects or dust floating in the air. It is assumed that the dust will be removed along with this. In particular, since this method uses a fine mist, it is possible to remove not only very fine dust but also bacteria and viruses, cleaning objects both physically and biologically. This effect is achieved. Viruses have conventionally been removed using air filters, but since viruses have a size of only 0.5 μ to 0.01 μ, it has been impossible to remove them sufficiently with air filters. Therefore, if the room is cleaned using the present invention, the chances of catching a cold will be greatly reduced, making it extremely suitable for use in hospitals, pharmacies, laboratories, maternity hospitals, etc.

In addition, because the method of the present invention has the feature of being free of germs, it can be used in food manufacturing factories for cleaning food and cleaning equipment, such as thawing frozen meat, salads, vegetables, fresh fish, and meat. It is also extremely suitable for use in food stores, supermarkets, etc. for preservation purposes, etc., and can also be used to freely produce raw ham, which has been subject to restrictions due to the risk of contamination with bacteria.

As described above, the present invention can be used not only for cleaning precision instruments but also for cleaning surgical tools due to its ultra-cleanliness. It is also highly expected to be used in medical fields such as lung cleansing.

[Brief explanation of drawings]

Fig. 1 shows one embodiment of the mist floating gas production device, Fig. 2 shows another embodiment thereof, and Fig. 3 shows the device shown in Fig. 2 when the center section is cut away. FIG. 4 schematically shows a total system when applied in an actual semiconductor manufacturing factory. Moreover, FIG. 5 is a diagram showing a heat exchanger that can be attached after the mist floating gas production device, and FIG. 6 is a cross-sectional view thereof. 1... Tank, 2, 45... Nozzle, 40...
Cyclone, 42... Gas inlet, 43... Fine water droplet floating gas outlet pipe, 50... Drip removal cyclone, 6
0...Air shower room, 70...Super clean room, 100...Heat exchanger.

Claims (1)

[Claims] 1. A method for cleaning an object, characterized by treating the object with a gas in which a large amount of mist of substantially 0.5 microns or less is suspended.