JP2006325642A - Ozone sterilizer and sterilization method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ozone sterilizer and sterilization method, wherein equipment constitution is simplified. <P>SOLUTION: The ozone sterilizer for sterilizing an object A to be sterilized, which is housed inside a treating chamber 11 and inside which ozone does not easily permeate, comprises: a compressor 12 connected to the treating chamber 11 for sucking air inside the treating chamber 11, reducing the pressure of the treating chamber 11 and compressing the air; a buffer tank 13 for housing compressed air from the compressor 12, which is formed into a volume capable of reducing the pressure of the treating chamber 11 to a prescribed pressure; an oxygen manufacturing device 14 for manufacturing oxygen by introducing the compressed air inside the buffer tank 13; and an ozone generator 15 for generating the ozone from the oxygen supplied from the oxygen manufacturing device 14 and supplying the ozone into the treating chamber 11. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ozone sterilization apparatus and a sterilization method used when sterilizing an object to be sterilized such as bedding.

  As a sterilizing apparatus for sterilizing and sterilizing bedding and the like, there has been proposed an apparatus for sterilizing an object to be sterilized by using ozone as a sterilizing gas and exposing the object to be sterilized in an ozone atmosphere.

  In general, an object to be sterilized such as a bed mat or a pillow contains a large amount of air inside, and thus it is difficult to sufficiently sterilize the inside of the object to be sterilized only by exposure to an ozone atmosphere. Therefore, by sucking and exhausting the processing chamber containing the object to be sterilized with a vacuum pump or the like, the air inside the object to be sterilized is removed, and ozone is easily penetrated into the object to be sterilized.

  Therefore, the ozone sterilizer includes a vacuum pump for sucking and exhausting air in the processing chamber in addition to the ozone generator and the oxygen production apparatus (PSA) connected to the ozone generator (for example, Patent Documents). 1).

JP 2001-37851 A

  However, in the conventional ozone sterilization apparatus, the air suction means included in the oxygen production apparatus and the air suction means for decompressing the inside of the processing space are configured by different systems. For this reason, a compressor connected to the PSA and a vacuum pump connected to the processing space are required, and there is a problem that duplication occurs in the devices constituting the ozone sterilizer.

  The duplication of components increases the initial cost and the operating cost, and increases the installation space for the ozone sterilizer.

  Then, the objective of this invention is providing the ozone sterilization apparatus and sterilization method which can solve the said subject and can simplify an apparatus structure.

  In order to achieve the above object, the invention of claim 1 is an ozone sterilization apparatus for sterilizing an object to be sterilized in which ozone does not easily permeate inside the processing chamber, and sucks air in the processing chamber connected to the processing chamber. A compressor that decompresses the processing chamber and compresses the air; a buffer tank that accommodates the compressed air from the compressor and that has a volume capable of reducing the processing chamber to a predetermined pressure; and An ozone sterilizer comprising an oxygen producing apparatus for introducing oxygen by introducing compressed air, and an ozone generating apparatus for generating ozone from oxygen supplied from the oxygen producing apparatus and supplying the ozone into the processing chamber. .

  A second aspect of the present invention is the ozone sterilization apparatus according to the first aspect, wherein an ozone decomposition catalyst unit is connected between the processing chamber and the compressor.

According to a third aspect of the present invention, the volume V _b [m ³ ] of the buffer tank is V [m ³ ], the pressure after depressurization of the process chamber is P [MPa], When the rated pressure is P _b [MPa] and the atmospheric pressure is P ₀ [MPa], the following formula:
V _b = (P ₀ −P) V / (P _b −P ₀ )
It is an ozone sterilizer of Claim 1 or 2 formed so that it may satisfy | fill.

  According to a fourth aspect of the present invention, the oxygen producing apparatus has a plurality of adsorption cylinders for introducing compressed air from the buffer tank to adsorb nitrogen and flowing oxygen to the ozone generator, and a switching valve for switching the adsorption cylinders. It is an ozone sterilizer in any one of Claims 1-3 provided with these.

  The invention of claim 5 is an ozone sterilization method for sterilizing an object to be sterilized in which ozone does not easily penetrate into the inside of the processing chamber. The processing chamber is configured by sucking air in the processing chamber with a compressor connected to the processing chamber. The compressed air is stored in a buffer tank formed in a volume capable of reducing the pressure in the processing chamber to a predetermined pressure, and the compressed air is introduced into an oxygen production apparatus connected to the buffer tank. This is an ozone sterilization method for producing oxygen, supplying oxygen to an ozone generator connected to an oxygen production apparatus to generate ozone, and supplying the ozone into the treatment chamber to sterilize the object to be sterilized.

  According to the invention of claim 6, while supplying compressed air from the buffer tank to the processing chamber after ozone sterilization, air containing ozone in the processing chamber is sucked into the compressor through the ozone decomposition catalyst section, and through the buffer tank. It is the ozone sterilization method of Claim 5 made to circulate.

  According to the present invention, an excellent effect that the configuration of the apparatus can be simplified is exhibited.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic view showing a preferred embodiment of the ozone sterilization apparatus of the present invention.

  The ozone sterilization apparatus 10 according to the present embodiment includes a processing chamber 11 that houses the article A to be sterilized, a compressor (compressor) 12 that is connected to the processing chamber 11, and a buffer tank ( A pressure tank) 13, an oxygen production device 14 connected to the buffer tank 13, and an ozone generator (ozonizer) 15 connected to the oxygen production device 14 and the processing chamber 11.

  The compressor 12, the buffer tank 13, the oxygen production device 14, and the ozone generator 15 are provided outside the processing chamber 11, and the compressor 12 is connected to the processing chamber 11 via the indoor gas suction line 16, and the ozone generator 15 Is connected to the processing chamber 11 via an ozone supply line 17.

  The processing chamber 11 may be an airtight space that can accommodate the article to be sterilized A. Examples of the processing chamber 11 include a room in a building or a portable bag or box.

  The article to be sterilized A to be sterilized by the ozone sterilizer 10 is particularly effective for bedding (bed mats and pillows) and the like containing air therein, but also for sterilizing linen products such as sheets that hardly contain air. Can be used.

  The compressor 12 is a device that sucks the gas in the processing chamber 11 and pumps it to the buffer tank 13. The buffer tank 13 is a tank that temporarily stores the compressed air compressed by the compressor 12, and is formed in a volume that can accommodate the air in the processing chamber 11 until the inside of the processing chamber 11 is depressurized to a predetermined pressure. Yes.

The oxygen production apparatus (PSA: Pressure Swing Adsorption) 14 includes a plurality of (two in FIG. 1) adsorption cylinders 18 and a switching valve 19 that switches a path of air flowing into each adsorption cylinder 18. The adsorption cylinder 18 is provided with a medium that adsorbs nitrogen, and removes nitrogen from the air to flow oxygen. In the oxygen production apparatus 14, the adsorption cylinder 18 is switched between the nitrogen adsorption state and the nitrogen release (medium regeneration) state by controlling the opening and closing of the switching valve 19 provided in the line on the buffer tank 13 side of each adsorption cylinder 18. .

  The ozone generator 15 is a device that generates oxygen from the supplied oxygen as a raw material and supplies the ozone to the processing chamber 11. The ozone generator 15 has an oxygen inlet (not shown) side connected to the oxygen production device 14 and an ozone outlet (not shown) side connected to the processing chamber 11 via an ozone supply line 17. Examples of the ozone generator 15 include a plasma discharge type ozonizer. The ozone supply line 17 is provided with an ozone supply valve 24.

  Further, an ozone decomposition catalyst unit 21 for removing ozone from air containing ozone is provided in the middle of the indoor gas suction line 16. The buffer tank 13 is directly connected to the processing chamber 11 and is provided with an air supply line 22 for sending the gas in the buffer tank 13 to the processing chamber 11, and the air supply line 22 is provided with a leak valve 23.

  Next, the operation method of the ozone sterilizer 10 will be described.

  First, the leak valve 23 and the ozone supply valve 24 are closed, and the air in the processing chamber 11 is sucked by the compressor 12. The sucked air is compressed by the compressor 12 and the compressed air is stored in the buffer tank 13. At this time, the inside of the processing chamber 11 is depressurized due to air suction, and the air in the sterilized object A in the processing chamber 11 is also sucked (deaerated).

Here, the volume V _b of the buffer tank 13 necessary for depressurizing the processing chamber 11 to a desired pressure is determined in relation to the volume of the processing chamber 11 and the pressure after depressurization, and is derived from Boyle's law. The When the volume of the processing chamber 11 is V [m ³ ], the pressure of the processing chamber 11 after depressurization is P [MPaG], and the rated pressure of the buffer tank 13 is P _b [MPaG], the buffer tank volume V _b [ m ³ ] is
V _b = (− P / P _b ) V (1)
It is represented by For example, when the buffer tank 13 that can be pressurized to 5 atm (0.4 MPaG) is used, the volume of the buffer tank 13 may be ¼ that of the processing chamber 11. As a specific example, the volume of the buffer tank 13 necessary for depressurizing the processing chamber having a volume of 2 m ³ to −0.1 MPaG is 0.5 m ³ .

  In the present embodiment, the volume of the buffer tank 13 with respect to the volume of the processing chamber 11 is set so that the chamber pressure after the pressure reduction of the processing chamber 11 is −0.09 to −0.05 [MPaG] (0.01 to 0.05 [MPa]). The rated pressure of the buffer tank 13 is preferably 0.1 to 15 [MPaG] (0.2 to 15 [MPa]).

In the above equation (1), each pressure unit is expressed in gauge pressure (unit [MPaG]). When each pressure is expressed in absolute pressure (unit [MPa]), the volume V _b of the buffer tank 13 is When the pressure of atmospheric pressure is P ₀ , it is expressed by the following equation (2).

V _b = (P ₀ −P) V / (P _b −P ₀ ) (2)
After reducing the pressure in the processing chamber 11 to a predetermined pressure, the compressor 12 is stopped or a valve (not shown) provided between the compressor 12 and the buffer tank 13 is closed.

  Next, when the switching valve 19 of the oxygen production apparatus 14 is opened, the compressed air in the buffer tank 13 is supplied to the oxygen production apparatus 14. The ozone supply valve 24 is also opened together with the switching valve 19.

  In the oxygen production apparatus 14, nitrogen in the air is absorbed by the adsorption cylinder 18, and oxygen is supplied to the ozone generator 15. Specifically, one switching valve 19 is opened, the other switching valve 19 is closed, and one adsorption cylinder 18 is adsorbed with nitrogen. After a predetermined time, the switching valves 19 are opened and closed in reverse, the adsorption cylinder 18 having the switching valve 19 opened adsorbs nitrogen, and the adsorption cylinder 18 having the switching valve closed closes the nitrogen (regenerating the adsorption medium). To do). The switching valves 19 and 19 are alternately opened and closed, and oxygen is separated from the air so that the adsorption cylinders 18 and 18 are alternately switched between a nitrogen adsorption state and a nitrogen release (regeneration) state.

  At this time, the nitrogen released from the adsorption cylinder 18 may be returned to the processing chamber 11 through a line (not shown), or may be supplied to the processing chamber 11 through the ozone supply line 17 together with ozone gas.

  The oxygen separated from the air by the oxygen production device 14 becomes ozone by the ozone generator 15. The ozone generator 15 generates ozone from oxygen and supplies the ozone to the processing chamber 11 via the ozone supply line 17.

  As a result, ozone gas flows into the processing chamber 11 to create an ozone atmosphere. At this time, the article to be sterilized A expands (restores) the volume while absorbing ozone, so that the ozone penetrates not only to the surface of the article to be sterilized A but also to the inside of the article to be sterilized A. Can be fully sterilized.

  After sterilizing the article A to be sterilized, all of the leak valve 23 and the switching valve 19 of the oxygen production apparatus 14 are closed, and a valve (not shown) between the compressor 12 and the buffer tank 13 is opened, or the compressor 12 is driven again, and air containing ozone in the processing chamber 11 is sucked and decompressed. The ozone in the article A to be sterilized in the processing chamber 11 is also sucked (degassed) by the decompression. The sucked ozone is removed by passing through the ozonolysis catalyst unit 21, and only air is stored in the buffer tank 13. Next, the leak valve 23 is opened, and the air accommodated in the buffer tank 13 flows (returns) into the processing chamber 11.

  The ozone in the processing chamber 11 is removed by the ozone decomposition catalyst unit 21, and the circulation process of sending the air in the buffer tank 13 from which ozone has been removed to the processing chamber 11 is performed for a predetermined time or a predetermined number of times. Is removed sufficiently. Finally, after the ozone in the processing chamber 11 is sufficiently removed, the article A to be sterilized is taken out from the processing chamber 11 and the process is completed.

  In the ozone sterilizer 10, the compressor 12 depressurizes the inside of the processing chamber 11 and pumps air to the buffer tank 13. Therefore, it is not necessary to separately provide a vacuum pump for decompressing the processing chamber provided through the processing chamber 11 and can be omitted.

  The ozone sterilizer 10 generates ozone using oxygen in the air in the processing chamber 11 as a raw material. Therefore, it is not necessary to provide an oxygen supply source connected to the ozone generator 15, and can be omitted.

  Therefore, the ozone sterilization apparatus 10 according to the present embodiment has fewer devices constituting the apparatus than the conventional ozone sterilization apparatus, can be configured easily, and the installation space can be reduced.

  Next, another preferred embodiment of the ozone sterilizer will be described with reference to FIG.

  The basic components are substantially the same as those of the ozone sterilization apparatus 10 in FIG. 1 described above, and the same components are denoted by the same reference numerals as those in FIG. 1 and description thereof is omitted.

  As shown in FIG. 2, the ozone sterilizer 30 of the present embodiment accommodates a compressor 12, a buffer tank 13, an oxygen production device 14, an ozone generator 15, and an ozone decomposition catalyst unit 21 in a processing chamber 11. It is. The gas suction line 16, the ozone supply line 17, and the leak line 22 are opened in the processing chamber 11.

  Further, when the inside of the processing chamber 11 is in an ozone gas atmosphere, the compressor 12 and the oxygen production apparatus 14 are accommodated in protective cases 31 and 32, respectively, in order to protect the compressor 12 and the oxygen production apparatus 14 from ozone gas. . In the figure, the compressor 12 and the oxygen production device 14 are accommodated in protective cases 31 and 32, respectively, but a plurality of devices (for example, the compressor 12, the buffer tank 13, the oxygen production device 14, the ozone generation device 15 and the like) The ozone decomposition catalyst part 21) may be accommodated in one protective case.

  Further, a control device for operating each of the compressor 12, the oxygen production device 14, the ozone generator 15 and the like and the opening and closing of the valves 23 and 24 is provided outside the processing chamber 11 (not shown).

  The ozone sterilizer 30 according to the present embodiment has the same effects as the ozone sterilizer 10 according to the previous embodiment.

  In addition, the inside of the processing chamber 11 is completely or almost completely sealed, and air circulates in the apparatus 10 so that ozone used as a sterilizing gas is removed in the decomposition catalyst unit 21. Therefore, there is no delivery of air containing ozone gas between the inside of the processing chamber 11 and the outside of the apparatus, and the processing chamber 11 can be completely isolated.

It is a schematic diagram which shows the ozone sterilizer of this Embodiment. It is a schematic diagram which shows the ozone sterilizer of other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Ozone sterilizer 11 Processing chamber 12 Compressor 13 Buffer tank 14 Oxygen production apparatus 15 Ozone generator A A thing to be sterilized

Claims (6)

  In an ozone sterilization apparatus for sterilizing an object to be sterilized in which ozone is difficult to penetrate inside a processing chamber, a compressor which is connected to the processing chamber and sucks air in the processing chamber to decompress the processing chamber and compresses the air. A buffer tank that accommodates compressed air from the compressor and that is capable of reducing the pressure in the processing chamber to a predetermined pressure, and an oxygen production apparatus that introduces compressed air in the buffer tank to produce oxygen. An ozone sterilization apparatus comprising: an ozone generation apparatus that generates ozone from oxygen supplied from the oxygen production apparatus and supplies the ozone into the processing chamber.   The ozone sterilizer according to claim 1, wherein an ozone decomposition catalyst unit is connected between the processing chamber and the compressor. The volume V _b [m ³ ] of the buffer tank is such that the volume of the processing chamber is V [m ³ ], the pressure after depressurization of the processing chamber is P [MPa], and the rated pressure of the buffer tank is P _b [MPa]. ], And when the atmospheric pressure is P ₀ [MPa], the following formula:
V _b = (P ₀ −P) V / (P _b −P ₀ )
The ozone sterilizer according to claim 1 or 2, wherein the ozone sterilizer is formed to satisfy the above condition.   The oxygen production apparatus includes a plurality of adsorption cylinders for introducing compressed air from the buffer tank to adsorb nitrogen and flowing oxygen to the ozone generator, and a switching valve for switching the adsorption cylinders. 3. The ozone sterilizer according to any one of 3.   In the ozone sterilization method for sterilizing an object to be sterilized in which ozone is difficult to permeate inside the processing chamber, the processing chamber is decompressed by sucking the air in the processing chamber with a compressor connected to the processing chamber and the air is Compressed air is stored in a buffer tank formed in a volume capable of reducing the pressure inside the processing chamber to a predetermined pressure, and oxygen is produced by introducing the compressed air into an oxygen production apparatus connected to the buffer tank. An ozone sterilization method comprising supplying oxygen to an ozone generator connected to an apparatus to generate ozone and supplying the ozone into the treatment chamber to sterilize the article to be sterilized. 6. The compressed air from the buffer tank is supplied to the processing chamber after the ozone sterilization, and the air containing ozone in the processing chamber is sucked into the compressor through the ozone decomposition catalyst and circulated through the buffer tank. Ozone sterilization method.

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