JP2017164260A - Ozone sterilization method and ozone sterilization device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sterilization method and a sterilization device using ozone gas, capable of obtaining practically usable sterilization capability to an environment requiring sterilization as an object.SOLUTION: An ozone sterilization method includes an ozone gas supply step S11 for supplying ozone gas to the inside of a chamber 2 for partitioning an environment 1E requiring sterilization, a water sprinkling step S12 for sprinkling water to the inside of the chamber 2, and a circulation step S13 for circulating the atmosphere in the chamber 2 where ozone gas and water mist exist.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a method and apparatus for using ozone gas to sterilize an environment such as a beverage or food production facility.

In an aseptic filling system that fills a container with a soft drink or the like in an aseptic environment, the container and the environment are sterilized using a sterilizable medium such as a medicine or hot water (for example, Patent Document 1).
As a sterilizable medium, ozone (O ₃ ) gas is also known.

JP 2014-80207 A

Ozone gas is easier to handle in terms of temperature control and rinsing than sterilizers, and because of its strong oxidizing power, it can sterilize spore bacteria with shells. I want to put it to practical use.
Therefore, an object of the present invention is to provide a sterilization method and a sterilization apparatus that can obtain a sterilization ability sufficient for practical use in an environment that uses ozone gas and requires sterilization.

  The ozone sterilization method of the present invention includes an ozone gas supply step for supplying ozone gas to the inside of a chamber that partitions an environment that requires sterilization, a water spraying step for spraying water inside the chamber, and a mist of ozone gas and water. And a circulation step for circulating the atmosphere in the chamber.

  In the ozone sterilization method of the present invention, the circulation step is preferably performed immediately after the water spraying step is started.

  In the ozone gas supply step in the ozone sterilization method of the present invention, it is preferable to supply wet ozone gas obtained by humidifying ozone gas to the inside of the chamber.

  The ozone sterilization method of the present invention includes an ozone gas supply step for supplying wet ozone gas containing and humidified to the inside of a chamber that partitions an environment that requires sterilization, and in the chamber in which the wet ozone gas exists. And a circulation step for circulating the atmosphere.

  In the ozone gas supply step in the ozone sterilization method of the present invention, it is preferable to supply ozone gas or wet ozone gas to the inside of the chamber until the ozone gas concentration in the atmosphere in the chamber becomes 0.5% or more by volume% concentration.

  The ozone gas sterilization method of the present invention preferably includes a first sterilization step including a circulation step, and a second sterilization step of spraying warm water heated to 60 ° C. or more inside the chamber.

  An ozone gas sterilizer according to the present invention includes a chamber for partitioning an environment that requires sterilization, an ozone gas supply device that supplies ozone gas containing ozone to the inside of the chamber, a water spray device that sprays water to the inside of the chamber, and a chamber Circulating means for generating a circulating flow circulating in the chamber is provided in the inner atmosphere.

  The ozone gas supply device in the present invention preferably supplies wet ozone gas obtained by humidifying ozone gas to the inside of the chamber.

  The ozone sterilization apparatus of the present invention includes a chamber for partitioning an environment that requires sterilization, a wet ozone gas supply device that supplies wet ozone gas that contains ozone and is humidified, and an atmosphere in the chamber. And a circulation means for generating a circulation flow circulating in the chamber.

  An aseptic filling machine according to the present invention includes the above-described ozone sterilization apparatus and a filling apparatus that fills a container with contents in a chamber.

According to the present invention, ozone gas and mist-like water are separately supplied into the chamber, or ozone gas supplied into the chamber is supplied by supplying wet ozone gas into the chamber and circulating the atmosphere in the chamber. the O ₃ contained in the full advantage can be obtained sterilizing effect sufficient to practical use.

It is a top view which shows typically the aseptic filling machine which concerns on 1st Embodiment. (A)-(c) is a figure for demonstrating the sterilization method which concerns on 1st Embodiment. (A)-(c) is a figure for demonstrating the effect | action obtained by the circulating flow formed in the chamber in which ozone gas and water exist. It is a top view which shows typically the aseptic filling machine which concerns on 2nd Embodiment. It is a figure for demonstrating the sterilization method which concerns on 2nd Embodiment. It is a top view which shows typically the aseptic filling machine which concerns on 3rd Embodiment. It is a top view which shows typically the aseptic filling machine which concerns on the modification of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
In each embodiment described below, an aseptic filling machine including the sterilization apparatus of the present invention will be described as an example.
[First Embodiment]
First, the configuration of the aseptic filling machine 1 will be briefly described with reference to FIG.
The aseptic filling machine 1 cleans and sterilizes a container (not shown) while filling the container with a beverage such as a soft drink, and then closes the mouth of the container.
Processing by the aseptic filling machine 1 is performed in a chamber 2 that is at a positive pressure with respect to the atmosphere.
The aseptic filling machine 1 includes a chamber 2, a sterilization device 15 disposed in the chamber 2, a filling device 11, and a capper 12. A container transport device is configured including the sterilizer 15, the filling device 11, the capper 12, the conveyors 13 and 14, a plurality of rotating bodies 16, and the like. The chamber 2 is divided into a first section where the sterilizer 15 is disposed and a second section where the filling device 11 and the capper 12 are disposed by a partition (not shown). The pressure in the second compartment is set higher than the pressure in the compartment.
In addition, the structure of a conveying apparatus is not restricted to what was illustrated, It can comprise suitably.

  The configuration of the container is not particularly limited. The container is, for example, a bottle formed from a resin material such as PET (Polyethyleneterephthalate) or a bottle can formed from a metal material such as an aluminum alloy.

The chamber 2 defines an environment 1E in which sanitation needs to be ensured by sterilization when filling a beverage.
The aseptic filling machine 1 includes an ozone sterilizer 10 that sterilizes the environment 1E, that is, the inside of the chamber 2. The environment 1E is sterilized by the ozone sterilizer 10 at a predetermined frequency.
The objects to be sterilized by the ozone sterilizer 10 include, for example, the sterilizer 15, the filling device 11, the capper 12, the conveyors 13 and 14, the rotating body 16 and the like, It is an internal space of the chamber 2. That is, the entire interior of the chamber 2 including the members disposed in the chamber 2, the chamber 2 itself, and the gas in the chamber 2 is sterilized by the ozone sterilizer 10. In the chamber 2 thus sterilized, the aseptic filling machine 1 sterilizes the container using, for example, medicine or hot water or ozone gas while conveying the container, and puts it inside the clean container. Fill with beverage (contents).

The present embodiment is characterized in that in a state where ozone (O ₃ ) gas and water mist exist in the chamber 2, the atmosphere 2 A in the chamber 2 is flowed to circulate in the chamber 2.
Hereinafter, the configuration of the ozone sterilizer 10 that sterilizes the environment 1E in the chamber 2 will be described.
The ozone sterilizer 10 (FIG. 1) includes the chamber 2, the ozone gas supply device 3, the water mist supply device 4 (water spray device), the circulation fan 5, and the hot water spray device 6.

The ozone gas supply device 3 supplies ozone gas containing ozone into the chamber 2. The ozone gas supply device 3 includes an ozone gas generator 31 and a supply unit 32 that supplies the generated ozone gas into the chamber 2. Since ozone gas is heavier than air, it is preferable that ozone gas is supplied into the chamber 2 from above through the supply unit 32.
The ozone gas generator 31 uses oxygen (O ₂ ) gas as a raw material to generate a gas in which part of the oxygen gas is replaced with ozone (O ₃ ) gas. It is also possible to use other gas containing oxygen, such as air, as the source gas.

In this specification, the “ozone gas” includes a gas in which ozone (O ₃ ) gas and other gas such as oxygen (O ₂ ) gas are mixed. The ozone concentration in such a mixed gas is typically about 10% to 20% in volume% concentration.

There are a silent discharge method, an electrolysis method, an ultraviolet lamp method, and the like as a method for generating ozone. The silent discharge method is used for industrial applications, and it is preferable to apply the silent discharge method, but it does not prevent other methods from being adopted. Here, silent discharge is a discharge phenomenon observed when a dielectric is provided between parallel electrodes, oxygen gas is supplied therebetween, and an alternating high voltage is applied between the two electrodes. . Electrons e are emitted into the gas by this silent discharge. A step (1) of causing the electrons e to collide with a stable oxygen molecule O ₂ to dissociate the oxygen molecule O ₂ into an oxygen atom O, an oxygen atom O, an oxygen molecule O ₂ , and a third substance M (for example, Ozone is generated by the step (2) in which a three-body collision including nitrogen molecules occurs. The ozone gas includes a third substance.
Step (1) O2 + e → 2O + e
Step (2) O + O2 + M → O3 + M
Moreover, ozone concentration by PSA method (Pressure Swing Adsorption: pressure swing method) may be used together as needed.

The water mist supply device 4 includes a nozzle 41 connected to a water supply source such as tap water, and sprays water into the chamber 2 through the nozzle 41. Mist water (water mist) is sprayed from the small opening of the nozzle 41.
Water can be misted by a known appropriate method. For example, mist can be sprayed from the nozzle 41 by pumping water with a pump or compressed air. Alternatively, the mist of water from the nozzle 41 can also be obtained by a jet type that sucks up water using a high-speed air flow and makes it mist, or an ultrasonic type that makes water mist by irradiating water with ultrasonic waves. Can be sprayed.

  It is sufficient if at least one water mist supply device 4 is provided in the ozone sterilization device 10, but two or more water mist supply devices 4 may be provided in the ozone sterilization device 10. For example, the water mist supply device 4 can be provided at a position indicated by a broken line.

Ozone gas exhibits a bactericidal action by chemically reacting with bacteria (organic matter) via water (H ₂ O).
As water used with ozone gas for the sterilization of environment 1E, normal temperature water from a general water supply can be used. Water is inexpensive and does not require drainage treatment.
Since strong sterilizing power is obtained with the reaction via water, water itself does not need sterilizing power, but heated water, hydrogen peroxide (H ₂ O ₂ ), peracetic acid (CH ₃ COOOH), etc. The use of acidic water to which the above chemicals are added is also permitted for the purpose of increasing the sterilizing ability. When water is heated, the reaction is promoted and the sterilizing power is improved. Acidic water has the effect of stabilizing the ozone concentration.
In the present specification, “water” includes warm water and acidic water.

The circulation fan 5 generates a circulation flow FC circulating in the chamber 2 in the atmosphere 2 </ b> A in the chamber 2. Here, a circulation fan 5 is installed inside the chamber 2. As the blade of the circulation fan 5 rotates, the gas in the chamber 2 is sucked into the circulation fan 5 and sent out from the circulation fan 5, whereby the gas is circulated in the chamber 2.
Here, “circulation” refers to circulation in the chamber 2 by applying a forced flow to the entire atmosphere 2A in the chamber 2 without including natural convection.
As the circulation fan 5, an appropriate blower such as a centrifugal fan or an axial fan, or a blower can be used.
In addition, in order to supply aseptic air into the aseptic chamber 2, the outside air intake path of the fan filter unit installed on the ceiling of the chamber 2 is closed with a damper or the like, and is replaced with the circulation fan 5 by changing to the inside air circulation. It is also possible to do.

The hot water spraying device 6 sprays hot water heated to 60 ° C. or more into the chamber 2. This hot water spraying device 6 includes a sterilized water supply source 61 such as a tank for storing sterilized water, a heater 62 for heating sterilized water, and a pump 63 for pumping heated sterilized hot water (hereinafter simply referred to as hot water). And a sprinkler 64 for spraying hot water into the chamber 2. The sprinkler 64 scatters hot water from above the device installed in the chamber 2 by the nozzle 64A.
The hot water spraying device 6 may be configured to include a nozzle that injects hot water into the chamber 2 instead of the sprinkler 64.

In the present embodiment, the environment 1E in which the container is filled with the beverage is sterilized by the method described below.
First, as shown in FIG. 2A, ozone gas is blown into the chamber 2 by the ozone gas supply device 3, and the chamber 2 is filled with ozone gas (ozone gas supply step S11). It is preferable to supply ozone gas into the chamber 2 until the ozone gas concentration of the atmosphere 2A in the chamber 2 becomes 0.5% or more in terms of volume% concentration. Although it is necessary to consider the sterilization time allowed for the sterilization of the environment 1E, it is preferable to fill the chamber 2 with ozone gas having a concentration as high as possible from the viewpoint of enhancing the sterilization ability.

  In the ozone gas supply step S11, the circulation fan 5 may be stopped, but it is preferable to operate the circulation fan 5 to circulate the atmosphere 2A in the chamber 2 because the concentration of ozone gas in the chamber 2 becomes uniform.

  Following or in parallel with the ozone gas supply step S11, as shown in FIG. 2 (b), the water mist supply device 4 operates to circulate the fan 5 while spraying water into the chamber 2, and thereby the inside of the chamber 2 The atmosphere 2A is circulated (water spraying step S12 and circulation step S13). At this time, ozone gas and water mist are present in the chamber 2. A circulating flow FC that circulates in the chamber 2 is formed in the atmosphere 2 </ b> A in the chamber 2.

  When water is sprayed in the chamber 2, the water adheres to the members of the apparatus in the chamber 2 and flows while the water mist is caught in the circulating flow FC in the chamber 2. Although water will drop by its own weight on the members and floors of the device in the chamber 2, while the water mist is caught in the circulating flow FC and flows in the atmosphere 2 </ b> A, a high sterilizing effect will be described later. Can be obtained.

The water mist sprayed from the nozzle 41 of the water mist supply device 4 rides on the circulating flow FC and is diffused throughout the chamber 2. As the mist sprayed from the nozzle 41 is finer, it can be wet throughout the chamber 2 with less water. For example, by spraying water from the nozzle 41 in an amount of 0.1 to 10 L (liter) per square meter of the surface area of the inner wall 2W of the chamber 2, the inner wall 2W of the chamber 2 or the device installed in the chamber 2 The entire member can be uniformly wetted with water. The particle size of the water mist is, for example, several μm to several tens of μm.
The amount of water sprayed is more preferably 0.5 to 2.0 L / m ² . The amount of water illustrated is the total amount of water sprayed into the chamber 2. When two water mist supply devices 4 are used, for example, half of each water mist supply device 4 is sprayed. .

In the water spraying step S12 and the circulation step S13, a gas-liquid interface between ozone gas and water is formed in the chamber 2 everywhere.
Here, the “gas-liquid interface” corresponds to, for example, an interface between water adhering to the inner wall 2W of the chamber 2 and the surrounding ozone gas. It also corresponds to the gas-liquid interface existing on the surface of the water mist that moves while being caught in the circulating flow FC. In the present specification, the “gas-liquid interface” includes these gas-liquid interfaces.
At the gas-liquid interface where the ozone gas and water are in contact, the ozone gas reacts with the organic substance via the water, and the organic substance is decomposed by the oxidizing power that expresses radicals such as hydroxy radicals generated during the reaction. This oxidizing power is strong, and even a bacterium having a shell such as a spore bacterium can be destroyed by killing the shell.

Here, the sterilization ability obtained by using ozone gas also depends on the concentration of ozone gas. As described above, the ozone gas concentration in the chamber 2 is, for example, 0.5% in volume% concentration and cannot be said to be high. Therefore, a gas-liquid interface between ozone gas and water is formed everywhere in the chamber 2 within the time required for sterilization of the environment 1E, for example, about 5 to 20 minutes, and the gas-liquid interface and the organic matter come into contact with each other. Increasing opportunities to do so contributes to improving the sterilizing ability.
In the present embodiment, the entire interior of the chamber 2 can be sufficiently sterilized by the sterilizing action associated with circulating the atmosphere 2A in the chamber 2 where ozone gas and water mist are present for a predetermined time.

By the steps S11 to S13 described above, the first sterilization step S1 using ozone gas and water is completed.
Then, as shown in FIG.2 (c), 2nd sterilization step S2 (warm water spraying step) sterilized by spraying warm water is performed. In the second sterilization step S2, mold is mainly targeted for sterilization.
In the second sterilization step S <b> 2, the hot water spraying device 6 sprays hot water of 60 ° C. or more downward from the ceiling of the chamber 2 through the sprinkler 64. Hot water is sprayed throughout the chamber 2 from the plurality of nozzles 64 </ b> A of the sprinkler 64.
The bacteria remaining after the first sterilization step S1 including mold are killed by the heat of hot water.
In order to ensure sufficient sterilization capability, it is preferable to keep the entire interior of the chamber 2 at 60 ° C. or higher by spraying warm water of 65 ° C. or higher from the nozzle 64A for 10 seconds or longer.
In the second sterilization step S2, the circulation fan 5 may be stopped, but when the circulation fan 5 is operated, an increase in the atmospheric temperature in the chamber 2 can be promoted.

The inside of the chamber 2 is washed away by the spraying of hot water. In other words, the second sterilization step S2 also serves as a residue rinse in the first sterilization step S1.
From the viewpoint of reliably performing sterilization and rinsing by hot water spraying, for example, it is preferable to spray hot water of about 50 to 200 L / m ² .

  Thus, the sterilization of the environment 1E is completed. Since ozone is an active species, the ozone gas in the chamber 2 eventually changes to oxygen gas and becomes stable. Since ozone gas can be easily rendered harmless by passing, for example, activated carbon or the like, the discharge treatment is easy.

Now, with reference to FIG. 3, the operation of the circulation flow FC formed in the chamber 2 supplied with ozone gas and water mist will be described.
3A to 3C show water W1 and W2 that adhere to the surface 7 of the member in the chamber 2 or exist in the atmosphere 2A, and ozone (O ₃ contained in the atmosphere 2A in the chamber 2). ) It captures a moment with gas. Description will be made assuming that bacteria (organic matter) are present on the surface 7 of the member.
At the gas-liquid interface 100 (FIG. 3A) where the ozone gas and the water W1 are in contact, the ozone gas reacts with the organic substance via the water W1. At that time, radicals such as hydroxy radicals are released, and the reaction proceeds while decomposing ozone gas and organic matter.

Here, if the atmosphere 2A in the chamber 2 does not flow and a gas such as oxygen (shown as “O ₂ ” in FIG. 3A) generated by the reaction with the organic substance stays in place. , Decomposition of organic matter present on the spot does not proceed any further.
However, in this embodiment, as shown in FIGS. 3A and 3B, the gas (O ₂ ) after reaction flows away from the site by the circulating flow FC in the chamber 2, and accordingly, newly Ozone gas (O ₃ ) flows in. That is, even if ozone gas is consumed due to the reaction with the organic substance, the ozone gas is supplied from the next to the next by the circulation flow FC, so that the organic substance can be reliably decomposed.

The reaction between the ozone gas and the organic matter via water occurs also in the circulating flow FC in the chamber 2. The surface of the water mist W2 entrained in the circulation flow FC corresponds to the gas-liquid interface 100 between ozone gas and water. Since the circulating flow FC flows while innumerable water mist W2 is entrained in ozone gas, the organic matter existing in the internal space of the chamber 2 or the surface 7 of the member disposed in the chamber 2 contacts the ozone gas and the water mist W2. And then decomposed. In the circulation flow FC, the water mist W2 flows so as to be relatively displaced with respect to the surrounding ozone gas, and the water mist W2 entrained in the circulation flow FC is also shown in FIGS. 3 (a) and 3 (b). Like the water W1 shown, new ozone gas is supplied one after another, so that sterilization can be performed efficiently.
The sterilizing effect can be enhanced by the water mist W2 that flows while being entrained in the circulating flow FC as described above. From the viewpoint of enhancing the sterilizing effect, it is preferable to operate the circulation fan 5 immediately after the start of the water spraying step S12 to form the circulation flow FC.

FIG. 3C shows a state in which the water mist W2 is attached to the surface 7 of the member immediately after the water spraying step S12 is started. Since it is immediately after the start of water spraying, the water mist W2 exists on the surface 7 of the member in a state of being separated from each other. When the water mist W2 adheres to the surface 7 as described above, the water-liquid interface 100 is compared with a water pool formed by another water mist W2 falling on the surface 7 and bonding the water mist W2 to each other. Large surface area. Moreover, since the periphery of the water mist W2 is open to the atmosphere 2A, the gas generated by the reaction with the organic substance at the gas-liquid interface 100 between the water mist W2 and the ozone gas smoothly flows out from the spot, and new ozone gas Is replaced. From the viewpoint described above, sterilization can be performed efficiently.
When the water mist W2 is present on the surface 7 of the member in a state of being separated from each other, that is, immediately after the water spraying step S12 is started, the concentration of ozone gas in the chamber 2 is higher than after that. The high concentration of ozone gas and the high sterilizing effect immediately after the start of the water spraying step S12 has a high contribution to improving the sterilizing ability.

  As suggested above, it is preferable that water is not sprayed in the chamber 2 and the surface 7 of the member is not wet before starting the water spraying step S12. If the water previously sprayed in the chamber 2 stays on the surface 7 of the member, the ozone gas is difficult to dissolve in the water. Therefore, when the ozone gas accesses the organic matter, the water becomes a barrier, and more Reaction between ozone gas and organic matter hardly occurs. Therefore, the 2nd sterilization step S2 which sprinkles warm water with sprinkler 64 needs to be performed after water spraying step S12 and circulation step S13.

As the phenomenon described with reference to FIGS. 3A to 3C occurs in combination, the ozone gas and the organic substance continuously react as a whole in the chamber 2, and the whole in the chamber 2 Sterilization will be performed throughout.
Therefore, even if the ozone gas concentration in the chamber 2 is low, it can be sufficiently sterilized within a predetermined sterilization time.

  By the way, as a method for sterilizing an object to be sterilized using ozone gas and water, other than that, water in which microbubbles of ozone gas are dissolved, or ozone water made by utilizing oxygen contained in water by electrolysis is used. A method of injecting into the chamber 2 by, for example, is also conceivable. However, since the concentration of ozone gas in water obtained by the method is low, it is difficult to obtain sufficient sterilizing ability even if a large amount of such water is used. The ozone gas concentration of water or ozone water in which microbubbles of ozone gas are dissolved is several mg / L to several tens mg / L in volume% concentration even when generated in a low temperature environment in order to increase the concentration. Even if a large amount of water is used, it is difficult to obtain sufficient sterilizing ability and the cost is high.

According to the present embodiment described above, ozone gas and water mist are separately supplied into the chamber 2, and the circulation gas FC is formed in the atmosphere 2 </ b> A in the chamber 2, thereby supplying the ozone gas supplied into the chamber 2. High sterilization ability can be obtained by making maximum use of O ₃ contained in the. According to the sterilization method of the present embodiment, a level 6D sterilization capability that reduces viable bacteria to 1/10 ⁶ within a required sterilization time can be realized. By supplying ozone gas into the chamber 2 and performing sterilization as described above until the volume% concentration is 0.5% or more in the ozone gas supply step S11, a level 6D sterilization capability can be obtained without replenishing the ozone gas. Has been confirmed.
The water and ozone gas used in the sterilization method of the present embodiment are cheaper in treatment and apparatus than in the case of using chemicals or hot water, and no odor remains in the container.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG.
In the following, the description will be focused on matters that are different from the first embodiment.
In the second embodiment, humidified ozone gas is used in order to further enhance the sterilization ability by the sterilization method using ozone gas and water.

As shown in FIG. 4, the ozone sterilizer 10 of the second embodiment includes a chamber 2, an ozone gas supply device 3 having a humidifying function, a water mist supply device 4, and a circulation fan 5.
The ozone gas supply device 3 (wet ozone gas supply device) includes an ozone gas generator 31, a humidifying unit 33 that humidifies the generated ozone gas, and a supply unit 32.
The humidifying unit 33 obtains wet ozone gas whose humidity is intentionally increased by including water in the ozone gas generated by the ozone gas generator 31. The humidity of the wet ozone gas is 90% or more, for example. Wet ozone gas is supplied into the chamber 2 by the supply unit 32.

  The ozone gas can be humidified by an appropriate method. Examples of humidification methods include a bubble dissolution method in which ozone gas is bubbled into water, a mixing method in which separately generated wet gas (oxygen, etc.) and ozone gas are mixed, and a shower that supplies ozone gas to water sprayed in a shower form The law etc. can be mentioned.

With reference to FIG. 5, the sterilization method of 2nd Embodiment which sterilizes environment 1E is demonstrated.
First, wet ozone gas is supplied into the chamber 2 by the ozone gas supply device 3 (wet ozone gas supply step S31). As in the first embodiment, it is preferable to fill the chamber 2 with wet ozone gas so that the ozone gas concentration is 0.5% or more. It is also preferable to operate the circulation fan 5 to make the ozone gas concentration uniform.

  Following or in parallel with step S31, water is sprayed into the chamber 2 by the water mist supply device 4, and the circulation fan 5 is operated (water spraying step S12 and circulation step S13). During steps S12 and S13, organic substances are decomposed at the gas-liquid interface 100 (FIG. 3) formed by ozone gas and water at various points in the chamber 2.

Furthermore, in the second embodiment, the following bactericidal action is obtained.
In the chamber 2, in addition to the water sprayed by the water mist supply device 4, moisture in the wet ozone gas is also present, so that the amount of moisture in the atmosphere 2 </ b> A in the chamber 2 is within the chamber 2 in the first embodiment. More than moisture. Sterilization is carried out by contacting organic substances with water vapor and ozone gas contained in the wet ozone gas. In the circulation flow FC in the chamber 2, the water vapor and the ozone gas in the wet ozone gas relatively flow, so that the ozone gas around the water vapor is sequentially replaced, so that the reaction between the ozone gas and the organic matter continues without stagnation. Done.
According to the second embodiment, the sterilizing ability can be increased by the amount of water vapor contained in the wet ozone gas.

  As a reference, the following table shows the results of a sterilization test conducted by supplying ozone gas of 10% in volume% concentration at a flow rate of 10 L / min to a certain point space and using the presence or absence of humidification by bubbling as a parameter. The sterilization target is Bacillus atrophaeus, and the sterilization time is 60 seconds.

LRV (Logarithmic Reduction Value) is a logarithmic reduction value of bacteria, and LRV “1” means sterilization performance that reduces 10 bacteria to one.
From the above table, when the ozone gas is humidified, the sterilization performance (ability) is improved.

According to the second embodiment, 6D sterilization ability can be realized even for mold.
Therefore, in the second embodiment, it is not necessary to spray hot water as the second sterilization step S2. Therefore, the cost required for aseptic water and heating can be suppressed. In addition, the sterilization time can be shortened by the amount that the hot water spraying is not required, or the sterilization ability using the ozone gas and water can be increased by the time for the omitted hot water spraying time, thereby improving the sterilization ability.

  Note that, in the second embodiment as well, the hot water spraying is not prevented as the second sterilization step S2. After step S31 and steps S12 and S13, or in parallel, it is allowed to spray hot water into the chamber 2 by the hot water spraying device 6 described above.

[Third Embodiment]
FIG. 6 shows a third embodiment of the present invention.
In the third embodiment, wet ozone gas is supplied into the chamber 2. The second embodiment is different from the second embodiment in that water is not sprayed into the chamber 2.
The ozone sterilizer 10 of 3rd Embodiment is provided with the chamber 2, the ozone gas supply apparatus 3 which has a humidification function, and the circulation fan 5, as shown in FIG.
The chamber 2 is filled with wet ozone gas, and a circulation flow FC is formed in the atmosphere 2A in the chamber 2 where the wet ozone gas exists. By doing so, since the ozone gas around the moisture flows relative to the moisture contained in the wet ozone gas, the reaction between the ozone gas and the organic matter through the water proceeds without stagnation. Since the wet ozone gas reaches every corner of the chamber 2 by the circulation flow FC, the surface of the member in contact with the wet ozone gas is sterilized throughout the interior of the chamber 2.

In addition to the above, as long as the gist of the present invention is not deviated, the configuration described in the above embodiment can be selected or changed to another configuration as appropriate.
As shown in the example shown in FIG. 7, a part of the gas in the chamber 2 is sucked into the duct 8 from one end of the duct 8 connected to the chamber 2 by the fan 9 arranged in the duct 8. It can also be configured such that the atmosphere in the chamber 2 is circulated by feeding gas into the chamber 2 from the end. In this case, the duct 8 and the fan 9 correspond to the circulation means.

  Costs can be reduced by collecting the ozone gas supplied into the chamber 2 and recycling it to the environment 1E and container sterilization.

1 Aseptic filling machine 1E Environment 2 Chamber 2A Atmosphere 2W Inner wall 3 Ozone gas supply device 4 Water mist supply device (water spraying device)
5 Circulation fan (circulation means)
6 Hot Water Dispersing Device 7 Surface 8 Duct 9 Fan 10 Ozone Sterilizer 11 Filling Device 12 Capper 13, 14 Conveyor 15 Sterilizer 16 Rotating Body 31 Ozone Gas Generator 32 Supply Unit 33 Humidification Unit 41 Nozzle 61 Aseptic Water Supply Source 62 Heater 63 Pump 64 Sprinkler 64A Nozzle 100 Gas-liquid interface FC Circulating flow S1 First sterilization step S2 Second sterilization step S11 Ozone gas supply step S12 Water spraying step S13 Circulation step S31 Wet ozone gas supply step W1 Water W2 Water mist

Claims (10)

An ozone gas supply step for supplying ozone gas to the inside of a chamber that partitions an environment that requires sterilization;
A water spraying step for spraying water inside the chamber;
Circulating the atmosphere in the chamber in which the ozone gas and the mist of water are present.
The ozone sterilization method characterized by the above-mentioned. Immediately after the water spraying step is started, the circulation step is performed.
The ozone sterilization method according to claim 1. In the ozone gas supply step,
Supplying wet ozone gas obtained by humidifying the ozone gas to the inside of the chamber;
The ozone sterilization method according to claim 1 or 2. An ozone gas supply step for supplying wet ozone gas containing ozone and being humidified to the inside of a chamber defining an environment requiring sterilization;
Circulating the atmosphere in the chamber in which the wet ozone gas exists.
The ozone sterilization method characterized by the above-mentioned. In the ozone gas supply step,
The ozone gas or the wet ozone gas is supplied to the inside of the chamber until the ozone gas concentration of the atmosphere in the chamber becomes 0.5% or more by volume% concentration.
The ozone sterilization method according to any one of claims 1 to 4, wherein A first sterilization step including the circulation step;
A second sterilization step of spraying hot water heated to 60 ° C. or more inside the chamber,
The ozone sterilization method according to any one of claims 1 to 5, wherein: A chamber that defines an environment that requires sterilization;
An ozone gas supply device for supplying ozone gas containing ozone to the inside of the chamber;
A water spraying device for spraying water inside the chamber;
A circulation means for generating a circulation flow circulating in the chamber in the atmosphere in the chamber;
An ozone sterilizer characterized by that. The ozone gas supply device
Supplying wet ozone gas obtained by humidifying the ozone gas to the inside of the chamber;
The ozone sterilizer according to claim 7. A chamber that defines an environment that requires sterilization;
A wet ozone gas supply device that supplies wet ozone gas that contains ozone and is humidified to the inside of the chamber;
A circulation means for generating a circulation flow circulating in the chamber in the atmosphere in the chamber;
An ozone sterilizer characterized by that. The ozone sterilizer according to any one of claims 7 to 9,
A filling device for filling the container with the contents in the chamber,
Aseptic filling machine characterized by that.

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