JP2007202628A - Sterilization apparatus and sterilization system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize sterilization performance in a sterilization system (1) by accurately measuring concentration of hydrogen peroxide generated by a hydrogen peroxide vapor generator (31) of a sterilization apparatus (10). <P>SOLUTION: The sterilization apparatus is equipped with an upstream temperature/humidity sensor (31a) for detecting a temperature and humidity of the atmosphere on the upstream side of the generator (31), a downstream temperature/humidity sensor (31b) for detecting a temperature and humidity of the atmosphere on the downstream side of the generator (31), and a concentration determining part (52) for determining the hydrogen peroxide concentration of the atmosphere on the down stream side from the temperature and the humidity on the upstream and downstream sides of the generator (31) and carries out sterilization operation by keeping the concentration of the hydrogen peroxide vapor at a prescribed value by the concentration determining part (52). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sterilization apparatus provided with a hydrogen peroxide vapor generator in a hydrogen peroxide generation flow path through which air flows, and a sterilization system for supplying hydrogen peroxide vapor to a processing chamber by the sterilization apparatus and sterilizing the room. Is.

  Conventionally, as a sterilization system of this type, a gas-suction passage provided with a vacuum pump for sucking a gas in the processing chamber in a sealable processing chamber (for example, a pharmaceutical manufacturing chamber) and hydrogen peroxide vapor are generated. A hydrogen peroxide supply passage provided with a hydrogen peroxide vapor generator, an air supply passage for supplying sterile air into the processing chamber, and a gas circulation passage for decomposing hydrogen peroxide with a catalyst while circulating the gas in the processing chamber; Are connected to each other (for example, see Patent Document 1).

  In the sterilization system disclosed in Patent Document 1, first, a vacuum pump is activated to evacuate a processing chamber, and then hydrogen peroxide is supplied into the processing chamber to perform sterilization. Next, aseptic air is introduced into the processing chamber from the air supply passage, and hydrogen peroxide is dispersed in the processing chamber. Then, when the sterilization of the processing chamber is completed by repeating the suction step by the vacuum pump, the hydrogen peroxide supply step, and the sterile air introduction step several times, the step of removing hydrogen peroxide from the processing chamber is performed. In this hydrogen peroxide removal step, the gas in the processing chamber is circulated while decomposing hydrogen peroxide by the catalyst in the gas circulation passage. By doing so, the hydrogen peroxide concentration in the processing chamber is lowered.

By the way, during the sterilization operation, the processing chamber is usually maintained at a constant hydrogen peroxide concentration. For this reason, a sensor for detecting the hydrogen peroxide concentration is provided in the processing chamber. As this sensor, for example, there is one that performs concentration measurement by near-infrared spectroscopy (see, for example, Patent Document 2). In addition, there is also a type in which concentration measurement is performed by absorbing hydrogen peroxide with a polymer film and measuring the amount of hydrogen peroxide.
JP-A-10-328276 JP-A-8-334460

  However, the conventional sensors used to detect the hydrogen peroxide concentration in the processing chamber are greatly affected by the measurement conditions (passing air volume, etc.) and installation conditions (installation method, installation position, etc.). Even if there are different sensors, the detected values may be different. In other words, it has been difficult for the conventional sensor to accurately determine the hydrogen peroxide concentration.

  The present invention has been made in view of the above points, and its purpose is to enable accurate measurement of the hydrogen peroxide concentration generated by the hydrogen peroxide vapor generator of the sterilization apparatus, and to improve the sterilization performance in the sterilization system. It is to stabilize.

  1st invention presupposes the sterilization apparatus provided with the hydrogen peroxide vapor | steam generator (31) in the hydrogen peroxide generation flow path (33) through which air flows.

  The sterilization apparatus includes upstream temperature / humidity detection means (31a) for detecting the temperature and humidity of the air upstream of the hydrogen peroxide vapor generator (31), and downstream of the hydrogen peroxide vapor generator (31). Based on the temperature and humidity on the upstream and downstream sides of the hydrogen peroxide vapor generator (31), the downstream temperature and humidity detection means (31b) for detecting the temperature and humidity of the side air And a concentration determination means (52) for determining the hydrogen peroxide concentration.

  In the first aspect of the invention, the concentration determination means (52) uses the concentration determination means (52) based on the amount of change in the downstream air temperature and humidity relative to the upstream air temperature and humidity of the hydrogen peroxide vapor generator (31). The hydrogen peroxide concentration immediately after the hydrogen oxide vapor generator (31) can be determined.

  According to a second invention, in the first invention, the concentration determination means (52) is configured so that the hydrogen peroxide generation flow path (33) is per unit time on the upstream side and the downstream side of the hydrogen peroxide vapor generator (31). The amount of water increase downstream is calculated from the amount of water passing through, and the amount of water increase is calculated based on the hydrogen peroxide concentration of the hydrogen peroxide solution used in the hydrogen peroxide vapor generator (31). A concentration calculation unit (52a) is provided that calculates the amount of hydrogen peroxide in the air by integrating the mass ratio, and calculates the concentration of hydrogen peroxide from the amount of hydrogen peroxide and the amount of passing air.

  In the second aspect of the invention, the amount of water increase on the downstream side is obtained from the amount of water passing through the upstream side and the downstream side of the hydrogen peroxide vapor generator (31). In the air downstream of the hydrogen peroxide vapor generator (31) in the hydrogen peroxide generation channel (33) based on the hydrogen peroxide concentration of the aqueous hydrogen peroxide solution used in the generator (31) The hydrogen concentration can be calculated.

  According to a third invention, in the first or second invention, the upstream temperature / humidity detection means (31a) and the downstream temperature / humidity detection means (31b) are connected to the upstream side and the downstream side of the hydrogen peroxide vapor generator (31). It is characterized by comprising a relative hygrometer that measures the relative humidity of the air on the side and a dry bulb thermometer that measures the dry bulb temperature of the air.

  In the third aspect of the invention, the relative humidity and the dry bulb temperature are measured both on the upstream side and the downstream side of the hydrogen peroxide vapor generator (31), and hydrogen peroxide vapor generation calculated based on these values is performed. The hydrogen peroxide concentration in the air downstream of the hydrogen peroxide vapor generator (31) is determined based on the increase in moisture downstream of the generator (31) and the hydrogen peroxide concentration of the hydrogen peroxide solution. It can be calculated.

  According to a fourth aspect of the present invention, in the first or second aspect, the upstream temperature / humidity detection means (31a) and the downstream temperature / humidity detection means (31b) are arranged upstream and downstream of the hydrogen peroxide vapor generator (31). It is characterized by comprising a dry bulb thermometer for measuring the dry bulb temperature of the air on the side and a wet bulb thermometer for measuring the wet bulb temperature of the air.

  In the fourth aspect of the present invention, the dry bulb temperature and the wet bulb temperature are measured both on the upstream side and the downstream side of the hydrogen peroxide vapor generator (31), and the hydrogen peroxide vapor calculated based on these values. Hydrogen peroxide concentration in the air downstream of the hydrogen peroxide vapor generator (31) based on the increased amount of moisture downstream of the generator (31) and the hydrogen peroxide concentration of the aqueous hydrogen peroxide solution Can be calculated.

  The fifth invention comprises a supply / exhaust mechanism (60) capable of supplying and exhausting air to and from the processing chamber (2) and a hydrogen peroxide vapor generator (31), and the processing chamber (2) is peroxidized. A sterilization system including a sterilizer (30) for supplying hydrogen vapor is assumed.

  In this sterilization system, the sterilizer (30) is constituted by the sterilizer according to any one of claims 1 to 4, and the hydrogen peroxide vapor generator (31) is overoxidized to the treatment chamber (2). Control means (50) for controlling the concentration of hydrogen peroxide in the air to a predetermined value by the concentration determination means (52) of the sterilizer (30) during the sterilization operation for supplying hydrogen vapor is provided. It is characterized by.

  In the fifth aspect of the present invention, the supply and exhaust mechanism (60) is controlled to supply and exhaust air to the processing chamber (2), while the hydrogen peroxide vapor generator (31) of the sterilizer (30) is used. During the sterilization operation in which hydrogen peroxide vapor is supplied to the processing chamber (2), the concentration determination means (52) controls to maintain the hydrogen peroxide concentration in the air at a predetermined value.

  The sixth invention is characterized in that, in the fifth invention, the air supply / exhaust mechanism (60) includes an air conditioner for supplying air with adjusted temperature and humidity to the processing chamber (2).

  In the sixth aspect of the invention, sterilization can be performed while air-conditioning the processing chamber (2). Here, in the sterilization process using hydrogen peroxide, the sterilization effect is higher in the low-humidity air than in the high-humidity air. Therefore, in the present invention, by maintaining the inside of the processing chamber (2) at a low humidity, the sterilization effect is stabilized at a high level.

  According to the present invention, the upstream temperature / humidity detecting means (31a) for detecting the temperature and humidity of the air upstream of the hydrogen peroxide vapor generator (31), and the downstream side of the hydrogen peroxide vapor generator (31) The downstream temperature / humidity detection means (31b) for detecting the temperature and humidity of the air, and the temperature and humidity on the upstream and downstream sides of the hydrogen peroxide vapor generator (31) By providing a concentration determination means (52) for determining the hydrogen oxide concentration, the amount of change in the temperature and humidity of the downstream air relative to the temperature and humidity of the upstream air of the hydrogen peroxide vapor generator (31) Based on this, the hydrogen peroxide concentration can be determined immediately after the hydrogen peroxide vapor generator (31). Therefore, the measurement conditions and installation conditions have little influence on the concentration determination value, and the determined hydrogen peroxide concentration is more accurate than before. Therefore, variation in sterilization performance can be prevented by performing the sterilization operation by controlling the hydrogen peroxide vapor supplied to the processing chamber (2) based on the above concentration.

  According to the second aspect of the invention, the amount of water increase on the downstream side is determined from the amount of water passing through the upstream side and the downstream side of the hydrogen peroxide vapor generator (31), and the amount of water increase and hydrogen peroxide Based on the hydrogen peroxide concentration of the hydrogen peroxide solution used in the steam generator (31), the hydrogen peroxide concentration on the downstream side of the hydrogen peroxide steam generator (31) can be calculated. Since the hydrogen peroxide concentration is obtained from the ratio of water and hydrogen peroxide in the aqueous hydrogen peroxide solution in the amount of water increase on the downstream side of the hydrogen peroxide vapor generator (31), the calculated value is accurate.

  According to the third aspect of the invention, as the upstream temperature / humidity detection means (31a) and the downstream temperature / humidity detection means (31b), the relative humidity of the air on the upstream side and the downstream side of the hydrogen peroxide vapor generator (31) Since a relative hygrometer for measuring the dry bulb and a dry bulb thermometer for measuring the dry bulb temperature of the air are used, the peroxidation in the air on the downstream side of the hydrogen peroxide vapor generator (31) with a simple configuration The hydrogen concentration can be measured reliably.

  According to the fourth aspect of the invention, the upstream temperature / humidity detection means (31a) and the downstream temperature / humidity detection means (31b) are dry air bulbs on the upstream and downstream sides of the hydrogen peroxide vapor generator (31). Since a dry bulb thermometer for measuring the temperature and a wet bulb thermometer for measuring the wet bulb temperature of the air are used, the hydrogen peroxide vapor generator (31) in the air downstream of the hydrogen peroxide vapor generator (31) can be configured with a simple configuration. The hydrogen peroxide concentration can be measured reliably.

  According to the fifth aspect of the present invention, the hydrogen peroxide vapor generator (31) of the sterilizer (30) is supplied while supplying and exhausting air to the processing chamber (2) by controlling the air supply / exhaust mechanism (60). During the sterilization operation for supplying hydrogen peroxide vapor from the treatment chamber (2) to the processing chamber (2), the concentration determination means (52) controls to maintain the hydrogen peroxide concentration at a predetermined value. Therefore, the hydrogen peroxide concentration in the processing chamber (2) during the sterilization operation in the sterilization system can be stabilized.

  According to the sixth invention, the air supply / exhaust mechanism (60) is provided with an air conditioner that supplies air with adjusted temperature and humidity to the processing chamber (2), thereby performing air conditioning of the processing chamber (2). The sterilization process can be performed. In sterilization using hydrogen peroxide, low-humidity air has a higher sterilization effect than high-humidity air. By maintaining the inside of the treatment chamber (2) at low humidity, sterilization can be achieved. The effect can be stabilized at a high level.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

-Overall configuration-
This embodiment relates to a sterilization system that performs air conditioning and sterilization processing in a processing room using a manufacturing room for pharmaceuticals or the like as a processing room. In this embodiment, the sterilization system (1) is configured for one processing chamber (2). As shown in FIG. 1 which is a piping system diagram of this embodiment, the sterilization system (1) includes an air conditioning system side circuit (10) and a sterilization system side circuit (sterilization apparatus) (30).

  The air conditioning system side circuit (10) of the sterilization system (1) includes an air supply passage (11) connected to the inlet of the processing chamber (2), and a return air passage connected to the outlet of the processing chamber (2) ( 12) and an exhaust passage (28). An air inlet from the supply passage (11) to the processing chamber (2) and an outlet from the processing chamber (2) to the return air passage (12) and the exhaust passage (28) have a HEPA filter (high efficiency particulate air filter) (14).

  Between the air supply passage (11) and the exhaust passage (28) (return air passage (12)), the air in the processing chamber (2) is supplied from the exhaust passage (28) (return air passage (12)). A return passage (15) for returning to the air passage (11) is connected. And the air-conditioning side circulation in which the air in the processing chamber (2) circulates by a part of the air supply passage (11), a part of the return air passage (12) (exhaust passage (28)) and the return passage (15) A passage (16) is formed. It should be noted that a mixing chamber (19) may be provided at the junction of the return passage (15) and the air supply passage (11) as indicated by a virtual line. In the exhaust passage (28) (return air passage (12)), a circulation fan (18) is provided on the upstream side of the connection portion with the return passage (15).

-Detailed configuration-
<Air conditioning system side circuit>
The air supply passage (11) is provided with an outside air processing air conditioner (13) configured as a dehumidifier and a sensible heat air conditioner (17) that only adjusts the temperature of air. The outside air processing air conditioner (13) and the sensible heat air conditioner (17) constitute an air conditioner.

  The outside air processing air conditioner (13) is separated into a first passage (13b) and a second passage (13c) by a partition wall (13a), and carries an adsorbent capable of adsorbing and desorbing moisture in the air. The honeycomb-shaped adsorption rotor (13d) is provided to be rotatable about a rotation shaft (not shown) provided along the partition wall (13a). In the first passage (13b), an outside air intake port (13e), a first cooling coil (13f), the adsorption rotor (13d), a fan (13j), and an air supply port (13k) are provided in this order from the upstream side. It has been. The second passage (13c) is provided with an outside air inlet (13e), a second heating coil (13m), an adsorption rotor (13d), and an exhaust port (13n). The exhaust port (13n) is connected to an exhaust fan (not shown).

  In the first passage (13b), moisture in the outside air (first air) cooled by the first cooling coil (13f) is adsorbed by the adsorption rotor (13d), and the first air is dehumidified. The first air is then blown out from the air supply port (13k). The adsorption rotor (13d) rotates continuously or intermittently, and the portion that has adsorbed moisture eventually moves into the second passage (13c). In the second passage (13c), outside air (second air) is heated by the second heating coil (13m) and then passes through the adsorption rotor (13d), whereby the adsorption rotor (13d) is regenerated. The regenerated portion of the adsorption rotor (13d) further rotates and moves toward the first passage (13b), so that the first air can be dehumidified again.

  In this outside air processing air conditioner (13), ducts are connected to the outside air intake port (13e) and the exhaust port (13n), respectively, and the medium performance filter (20) is connected to the duct on the outside air intake port (13e) side. Is provided.

  The sensible heat air conditioner (17) has an air inlet (17a), a cooling coil (17b), an electric heater (17e), a fan (17c), and an air outlet (17d) in order from the upstream side. Yes. A medium performance filter (20) is provided between the sensible heat air conditioner (17) and the outside air processing air conditioner (13). The return passage (15) is connected between the outside air processing air conditioner (13) and the medium performance filter (20) in the air supply passage (11).

  The air conditioning system side circuit (10) is provided with three air conditioning gas switching valves (56). Specifically, a first air-conditioning gas switching valve (56a) is provided between the sensible heat air conditioner (17) and the processing chamber (2) in the air supply passage (11). A second air conditioning gas switching valve (56b) is provided between the processing chamber (2) and the circulation fan (18) in the exhaust passage (28). A third air-conditioning gas switching valve (56c) is provided on the downstream side of the connection portion between the exhaust passage (28) and the return passage (15).

<Sterilization system side circuit>
The sterilization system side circuit (30) includes a main channel (34), a hydrogen peroxide generation channel (33), a hydrogen peroxide decomposition channel (35), a circulation side channel (37), and an exhaust side channel ( 54). One end of the main flow path (34) is connected downstream of the first air-conditioning gas switching valve (56a) in the air supply passage (11), and the other end is second in the return air passage (12) (exhaust passage (28)). It is connected upstream of the air-conditioning gas switching valve (56b). A part of the supply air passage (11), a part of the return air passage (12), and the main flow path (34) constitute a sterilization side circulation passage (32) through which the air in the processing chamber (2) circulates. .

  A sterilization side air conditioner (53) is provided in the main channel (34). The sterilization side air conditioner (53) is an air conditioner having the same configuration as the sensible heat air conditioner (17) and having a smaller processing air volume than the sensible heat air conditioner (17). The sterilization side air conditioner (53) has an air inlet (53a), a cooling coil (53b), an electric heater (53e), a fan (53c), and an air outlet (53d) in order from the upstream side. . The sterilization side air conditioner (53) has a processing air volume smaller than that of the sensible heat air conditioner (17), but may be greater than or equal to the sensible heat air conditioner (17).

  In the upstream part of the sterilization side air conditioner (53) of the main flow path (34), a hydrogen peroxide decomposition flow path (35), a circulation side path (37), and a hydrogen peroxide generation flow path (33) are arranged in order from the upstream side. Is connected. The circulation side passage (37) branches off from the hydrogen peroxide decomposition passage (35). That is, the portion composed of the hydrogen peroxide decomposition channel (35) and the circulation side channel (37) is in parallel with the main channel (34).

  The hydrogen peroxide generation channel (33) is provided with a sterilization gas generator (58), and the end opposite to the main channel (34) is open to the atmosphere. The sterilization gas generator (58) includes a dehumidifier (57) and a hydrogen peroxide vapor generator (31). The dehumidifier (57) dehumidifies the air taken from outside. The hydrogen peroxide vapor generator (31) generates hydrogen peroxide vapor by atomizing an aqueous solution of hydrogen peroxide. In this embodiment, a 35% aqueous hydrogen peroxide solution is used. The reason for dehumidifying the air with the dehumidifier (57) is that the hydrogen peroxide is more likely to evaporate in the low-humidity air. In this embodiment, the ratio of the air volume on the main flow path (34) side and the air volume on the hydrogen peroxide generation flow path (33) side is determined to be about 10: 1.

  The hydrogen peroxide generation channel (33) includes an upstream temperature / humidity sensor (upstream temperature / humidity detection means) (31a) that detects the temperature and humidity of the air upstream of the hydrogen peroxide vapor generator (31). A downstream temperature / humidity sensor (downstream temperature / humidity detection means) (31b) for detecting the temperature and humidity of the air downstream of the hydrogen peroxide vapor generator (31) is provided. The upstream temperature / humidity sensor (31a) and the downstream temperature / humidity sensor (31b) are respectively a relative hygrometer that measures the relative humidity of the air upstream and downstream of the hydrogen peroxide vapor generator, It is comprised with the dry bulb thermometer which measures bulb | ball temperature. Instead, the upstream temperature / humidity sensor (31a) and the downstream temperature / humidity sensor (31b) have dry bulb temperatures that measure the dry bulb temperature of the air upstream and downstream of the hydrogen peroxide vapor generator. A meter and a wet bulb thermometer that measures the wet bulb temperature of the air may be used.

  The hydrogen peroxide decomposition channel (35) is provided with a Pt catalyst that is a hydrogen peroxide decomposer (36) and an exhaust fan (55) from the main channel (34) side. The hydrogen peroxide decomposition flow path (35) has an end opposite to the main flow path (34) branched into a circulation side passage (37) and an exhaust side passage (54). The exhaust-side passage (54) is open to the atmosphere at the end opposite to the hydrogen peroxide decomposition passage (35), and an exhaust adjustment damper (29) is provided in the middle.

  The sterilization system side circuit (30) is provided with six sterilization gas switching valves (45). Specifically, a first sterilization gas switching valve (45a) is provided on the upstream side of the connection portion of the hydrogen peroxide decomposition channel (35) in the main channel (34). A second sterilization gas switching valve (45b) is provided upstream of the hydrogen peroxide decomposer (36) in the hydrogen peroxide decomposition channel (35). A third sterilization gas switching valve (45c) is provided between the connection part of the hydrogen peroxide decomposition flow path (35) and the connection part of the circulation side passage (37) in the main flow path (34). The circulation side passage (37) is provided with a fourth sterilization gas switching valve (45d). A fifth sterilization gas switching valve (45e) is provided on the downstream side of the sterilization gas generator (58) in the hydrogen peroxide generation flow path (33). A sixth sterilization gas switching valve (45f) is provided downstream of the sterilization side air conditioner (53) in the main channel (34).

<Air supply / exhaust mechanism and hydrogen peroxide supply mechanism>
In this sterilization system (1), an air supply / exhaust mechanism (60) that supplies and exhausts air to and from the processing chamber (2) during the sterilization operation is provided with an air supply passage (62) ( A supply device (61) provided on the inlet side to the processing chamber (2) in the hydrogen peroxide generation channel (33) and the main channel (34), and a pressure sensor for detecting the pressure in the processing chamber (2) (Pressure detection means) (63) and an exhaust device (65) provided in the air discharge passage (64) for discharging air from the processing chamber (2).

  The air supply device (61) includes a sterilization gas generator (58) provided in the hydrogen peroxide generation flow path (33) and a sterilization side air conditioner (53) provided in the main flow path (34). Yes. The sterilization gas generator (58) constitutes a hydrogen peroxide supply mechanism (70) including a hydrogen peroxide vapor generator (31). The sterilization side air conditioner (53) is provided with an air supply pressure adjustment mechanism (67) for adjusting the discharge pressure of the fan (53c). The fan (53c) is an inverter-controlled fan, and the supply air pressure adjusting mechanism (67) includes the fan (53c), a pressure sensor (not shown) provided on the discharge side, and a detection value thereof. And a controller for controlling the rotation speed of the fan motor.

  The exhaust device (65) includes a first sterilization gas switching valve (45a) provided in the main flow path (34), a second sterilization gas switching valve (45b) provided in the hydrogen peroxide decomposition flow path (35), and A hydrogen peroxide decomposer (36) and an exhaust fan (55) provided in the exhaust side passage (54) are provided. The first sterilization gas switching valve (45a) and the second sterilization gas switching valve (45b) constitute an opening / closing mechanism (66).

-Operation control-
Next, operation control and specific operation of the sterilization system (1) will be described.

  The sterilization system (1) includes a controller (control means) (50) for controlling the operation of the air conditioning system side circuit (10) and the sterilization system side circuit (30). The controller (50) is configured to perform a preparation operation, a sterilization operation, a dilution operation (a first dilution operation and a second dilution operation), and a steady operation.

  In addition, the controller (50) is configured to perform pressure sensors (62a, 62b) in the processing chamber (2) during the sterilization operation for supplying hydrogen peroxide vapor from the hydrogen peroxide supply mechanism (70) to the processing chamber (2). , 62c) includes an exhaust controller (exhaust control device) (51) for controlling the discharge amount of air from the processing chamber (2) by adjusting the opening / closing mechanism (66) based on the detected value. The exhaust controller (51) performs control such that the amount of air supplied to the processing chamber (2) by the air supply / exhaust mechanism (60) is larger than the amount of exhaust from the processing chamber (2), and the processing chamber (2) The inside is maintained at a slight positive pressure with respect to atmospheric pressure (atmospheric pressure outside the processing chamber (2)) (the gauge pressure is about 20 Pa or less, preferably about 5 to 10 Pa).

The controller (50) also includes a concentration determination unit (concentration) for determining the concentration of hydrogen peroxide in the downstream air based on the temperature and humidity upstream and downstream of the hydrogen peroxide vapor generator (31). Determination means) (52). The concentration determination unit (52) calculates the amount of water increase on the downstream side from the passing water amount per unit time on the upstream side and downstream side of the hydrogen peroxide vapor generator (31) in the hydrogen peroxide generation flow path (33). Calculate the amount of hydrogen peroxide by adding the mass ratio to water based on the hydrogen peroxide concentration of the hydrogen peroxide solution used in the hydrogen peroxide vapor generator (31). (For example, in the case of a 35% aqueous hydrogen peroxide solution, 65/35 is added, but more specifically, it may be calculated by taking into account the ratio of the molecular weight of H ₂ O and H ₂ O ₂ ) And a concentration calculating section (52a) for calculating the hydrogen peroxide concentration from the hydrogen peroxide amount and the passing air amount.

<Preparation operation>
The preparatory operation is a process of reducing the humidity of the processing chamber (2) by the outside air processing air conditioner (13) so that the humidity of the processing chamber (2) becomes the target humidity with the sterilization gas generator (58) stopped. In this operation, the amount of outside air introduced is about ½ of the state in steady operation described later, and the inside of the processing chamber (2) is reduced in humidity. In the preparatory operation, the target humidity of the processing chamber (2) is set to a predetermined value of 20% to 30% relative humidity. The target humidity is not limited to a range of 20% or more and 30% or less, and may be a range of 10% or more and 50% or less, for example. Moreover, in preparation operation, in preparation for sterilization, a manufacturing apparatus, such as a pharmaceutical, is opened and a simple look of fittings is performed. The air flow of this preparation operation is shown in FIG.

  At this time, each valve (56a, 56b, 56c) of the air conditioning system side circuit (10) is opened. On the other hand, each valve (45a, 45b, 45c, 45d, 45e, 45f) of the sterilization system side circuit (30) is closed.

  In this state, when the outside air processing air conditioner (13), the sensible heat air conditioner (17), and the circulation fan (18) are operated, the air dehumidified by the outside air processing air conditioner (13) is sensible heat air conditioner (17). The low-humidity air whose temperature is adjusted is supplied to the processing chamber (2) via the HEPA filter (14) on the inlet side.

  The air in the processing chamber (2) flows out through the HEPA filter (14) on the outlet side, circulates through the exhaust passage (28) by the circulation fan (18), and part of it flows to the air supply passage (11). It returns to the sensible heat air conditioner (17) and the remainder is exhausted from the outlet of the exhaust passage (28). The preparation operation is performed until the room temperature in the processing chamber (2) reaches 25 ° C. and the relative humidity reaches a predetermined value (for example, 30%). In the processing chamber (2), a temperature sensor and a humidity sensor are provided to detect temperature and humidity.

<Sterilization operation>
When the preparatory operation is completed, in order to stop the air supply from the air conditioning system side circuit (10) to the processing chamber (2), the outside air processing air conditioner (13) and the sensible heat air conditioner (17) that constitute the air conditioner And the circulation fan (18) are stopped, and the setting of the valve is switched to shift to the sterilization operation. The sterilization operation is performed by supplying hydrogen peroxide from the sterilization gas generator (58) to the processing chamber (2), thereby setting the concentration of hydrogen peroxide in the processing chamber (2) to a predetermined concentration (for example, 500 ppm). In this step, the concentration state is maintained for a predetermined time, and at the same time, the sterilization-side air conditioner (53) is used to maintain the processing chamber (2) at a slight positive pressure.

  In this sterilization operation, the operation control of the sterilization gas generator (58) includes an adjustment mode until the hydrogen peroxide concentration in the processing chamber (2) reaches a predetermined concentration, and a sterilization mode for maintaining the predetermined concentration. In each mode, the supply amount of hydrogen peroxide to the processing chamber (2) is adjusted. The air flow during this sterilization operation is shown in FIG. At this time, the valves (56a, 56b, 56c) of the air conditioning system side circuit (10) are closed. On the other hand, the valves of the sterilization system side circuit (30) are opened except for the fourth sterilization gas switching valve (45d).

  In this state, when the sterilization gas generator (58), the sterilization side air conditioner (53), and the exhaust fan (55) are operated, the air taken from outside is sent to the sterilization gas generator (58). The air that has flowed into the sterilization gas generator (58) is dehumidified by the dehumidifier (57) and then given oxygen peroxide vapor by the hydrogen peroxide vapor generator (31). The air (sterilization gas) containing a predetermined amount of hydrogen peroxide vapor merges with the air in the main flow path (34), the temperature is adjusted by the sterilization side air conditioner (53), and the supply pressure adjustment mechanism (67) Then, the pressure is adjusted and supplied to the processing chamber (2) through the HEPA filter (14) on the inlet side. As described above, the ratio of the amount of air flowing through the main channel (34) and the amount of air flowing through the hydrogen peroxide generating channel (33) is set to about 10: 1. By doing so, it is possible to obtain an effect of sufficiently diffusing hydrogen peroxide in the air and thus uniformly in the processing chamber (2).

  The sterilization gas in the processing chamber (2) flows out through the HEPA filter (14) on the outlet side, and flows from the exhaust passage (28) into the main channel (34) constituting the sterilization side circulation passage (32). Part of the sterilized gas that has flowed into the main flow path (34) flows directly through the main flow path (34), passes through the sterilization side air conditioner (53), and is then supplied to the treatment chamber (2), with the remainder being decomposed by hydrogen peroxide. It flows into the channel (35). The sterilization gas that has flowed into the hydrogen peroxide decomposition channel (35) is decomposed by the exhaust fan (55) after the hydrogen peroxide in the sterilization gas is decomposed by the hydrogen peroxide decomposer (36). It is discharged outside from the exit.

  The reason why the air in the sterilization side circulation passage (32) is exhausted from the exhaust side passage (54) is to control the indoor pressure of the processing chamber (2) accompanying the inflow of sterilization gas from the main flow path (34). The amount of air exhausted from the exhaust side passage (54) to the outside, that is, the flow rate of sterilization gas in the hydrogen peroxide decomposition channel (35), is measured by the pressure sensor (63) provided in the processing chamber (2). This is done by controlling the opening of the first sterilization gas switching valve (45a) and the second sterilization gas switching valve (45b) based on the value, but at this time, the amount of air supplied to the processing chamber (2) is processed. Control to increase the amount of exhaust from the chamber (2). As a result, the interior of the room is maintained at a positive pressure (slight positive pressure) with respect to the atmospheric pressure.

  The amount of hydrogen peroxide vapor supplied during this sterilization operation is determined by the controller (50) while the concentration determination unit (52) determines the concentration of hydrogen peroxide vapor downstream of the hydrogen peroxide vapor generator (31). The equipment is controlled and the hydrogen peroxide concentration in the processing chamber (2) is adjusted to the set value.

<Dilution operation>
After completion of the sterilization operation, the concentration of hydrogen peroxide in the processing chamber (2) is a predetermined concentration of about 500 ppm. In this high concentration state, even if the sterilization gas in the treatment chamber (2) is passed through the hydrogen peroxide decomposer (36) to decompose the hydrogen peroxide, the amount of hydrogen peroxide is large. The hydrogen peroxide concentration cannot be reduced to a level at which it can be discharged. Therefore, air is circulated between the processing chamber (2) and the hydrogen peroxide decomposer (36) until the concentration of hydrogen peroxide in the processing chamber (2) becomes a predetermined value (for example, 10 ppm) or less. A first dilution operation (circulation operation) is performed in which the hydrogen peroxide in the air is decomposed by the hydrogen peroxide decomposer (36) (FIG. 4). Then, while operating the outside air processing air conditioner (13) and sensible heat air conditioner (17) and supplying aseptic air treated with the HEPA filter (14) to the processing chamber (2), the inside of the processing chamber (2) A second dilution operation (exhaust operation) for discharging the air to the outside is performed (FIG. 5). If the concentration of hydrogen peroxide in the sterilization gas is 10 ppm (concentration at the end of the first dilution operation), it cannot be discharged to the outside as it is, but if it is 10 ppm or less, the hydrogen peroxide in the sterilization gas is decomposed into hydrogen peroxide. The concentration of hydrogen peroxide can be reduced to a level at which it can be discharged outside by being decomposed by the vessel (36).

(First dilution operation)
In the first dilution operation, the sterilization gas generator (58) is stopped and the sterilization side air conditioner (53) is operated. FIG. 4 shows the air flow during the first dilution operation.

  At this time, the setting of the air conditioning system side circuit (10) is basically the same as in the sterilization operation, and the outside air processing air conditioner (13), the sensible heat air conditioner (17), and the circulation fan (18) are stopped. Each valve (56a, 56b, 56c) is closed. On the other hand, the valves of the sterilization system side circuit (30) are opened except for the third sterilization gas switching valve (45c) and the fifth sterilization gas switching valve (45e), and the exhaust control damper (29) is closed. .

  When the sterilization side air conditioner (53) and the exhaust fan (55) are operated in this state, excess air in the air is circulated when the air circulates between the treatment chamber (2) and the hydrogen peroxide decomposer (36). Hydrogen oxide is decomposed by the hydrogen peroxide decomposer (36). The first dilution operation is performed until the hydrogen peroxide concentration becomes a predetermined value (10 ppm) or less.

  If the pressure in the processing chamber (2) decreases during the first dilution operation, the sterilization gas generator (58) is stopped and the fifth sterilization gas switching valve (45e) is opened to generate hydrogen peroxide. Outside air is introduced from the passage (33), and an operation for maintaining the inside of the processing chamber (2) at a predetermined pressure (for example, several tens of Pa in gauge pressure) is performed.

(Second dilution operation)
In the second dilution operation, the concentration of hydrogen peroxide further exceeds a predetermined value (10 ppm) while supplying air from the outside air treatment air conditioner (13) to the treatment chamber (2) via the HEPA filter (14) on the inlet side. This is a ventilation process in which exhaust is performed until the value becomes lower than 1 ppm (FIG. 5).

  At this time, the sterilization gas generator (58) and the circulation fan (18) are stopped. Each valve of the air conditioning system side circuit (10) opens only the first air conditioning gas switching valve (56a). On the other hand, each valve of the sterilization system side circuit (30) is in a state in which the first sterilization gas switching valve (45a) and the second sterilization gas switching valve (45b) are opened, and the exhaust control damper (29) is also opened. To do. Further, the exhaust fan (55) is operated.

  In this state, when the outside air treatment air conditioner (13), sensible heat air conditioner (17), and exhaust fan (55) are operated, the temperature and humidity of the outside air treatment air conditioner (13) and sensible heat air conditioner (17) are reduced. Sterile air that has been adjusted and purified by the HEPA filter (14) on the inlet side is supplied to the processing chamber (2) and uniformly mixed with the sterilizing gas in the processing chamber (2). The diluted sterilization gas flows out of the processing chamber (2) through the HEPA filter (14) on the outlet side. The sterilizing gas flows from the exhaust passage (28) into the hydrogen peroxide decomposition passage (35) through the main passage (34) of the sterilization system side circuit (30). The sterilization gas that has flowed into the hydrogen peroxide decomposition channel (35) is decomposed by the hydrogen peroxide decomposer (36) and discharged from the outlet of the exhaust side passage (54) to the outside. The

  In this second dilution operation, unlike the first dilution operation, the air that has passed through the hydrogen peroxide decomposer (36) is not returned to the processing chamber (2), so that the processing chamber is shorter in time than the first dilution operation. It is possible to reduce the concentration of hydrogen peroxide in (2). Moreover, the supply of air to the processing chamber (2) is performed using an outside air processing air conditioner (13) and a sensible heat air conditioner (17) constituting the air conditioner. These air conditioners (13, 17) are configured as devices that can supply a larger volume of air than the sterilization side air conditioner (53), so the amount of air exchanged in the processing chamber (2) per unit time Is greater than in the first dilution operation. Also in this point, it is possible to reduce the concentration of hydrogen peroxide in the processing chamber (2) in a shorter time than in the first dilution operation.

  The second dilution operation is performed until the hydrogen peroxide concentration in the processing chamber (2) is about 1 ppm or less. At that time, the first sterilization gas switching valve (45a) and the second sterilization gas switching valve are used in order to maintain the indoor pressure at a pressure lower than the steady value (for example, about 15 Pa as a gauge pressure) by measures against building air leakage. Adjust each opening of (45b).

  Also, during the transition from the first dilution operation to the second dilution operation, the outside air treatment air conditioner (13), the sensible heat air conditioner (17), and the exhaust fan (55) are started slowly to avoid sudden changes in the room pressure. And make a stable transition.

<Normal operation>
Steady operation is a process of exhausting the air in the processing chamber (2) to the outside in order to ventilate the inside of the processing chamber (2) and maintain the room pressure while taking in the outside air processed by the outside air processing air conditioner (13). . FIG. 6 shows the air flow in the steady operation. The air flow is substantially the same as that in the second dilution operation, but differs in that the air in the processing chamber (2) is discharged from the exhaust passage (28) instead of the exhaust side passage (54).

  At this time, each valve (56a, 56b, 56c) of the air conditioning system side circuit (10) is opened. On the other hand, the valves (45a, 45b, 45c, 45d, 45e, 45f) and the exhaust control damper (29) of the sterilization system side circuit (30) are closed. Further, the exhaust fan (55) is stopped and the circulation fan (18) is operated.

  In this state, when the outside air treatment air conditioner (13), sensible heat air conditioner (17), and circulation fan (18) are operated, the temperature and humidity of the outside air treatment air conditioner (13) and sensible heat air conditioner (17) are reduced. Aseptic air that has been adjusted and purified by the HEPA filter (14) on the inlet side is supplied to the processing chamber (2). Aseptic air in the processing chamber (2) flows out of the processing chamber (2) through the HEPA filter (14) on the outlet side. Most of this sterile air is discharged from the outlet of the exhaust passage (28) through the third air-conditioning gas switching valve (56c), and part is returned to the air supply passage (11) from the return passage (15), It further flows to the sensible heat air conditioner (17). In the steady operation, the temperature and humidity of the processing chamber (2) are maintained at the set values and the aseptic state is maintained.

-Effect of the embodiment-
In this embodiment, based on the amount of change in the temperature and humidity of the downstream air with respect to the temperature and humidity of the upstream air of the hydrogen peroxide vapor generator (31), the hydrogen peroxide vapor generator (31) Immediately after that, the hydrogen peroxide concentration can be determined. In particular, the amount of water increase on the downstream side is determined from the amount of water passing through the upstream and downstream sides of the hydrogen peroxide vapor generator (31). The hydrogen peroxide concentration in the air can be calculated based on the hydrogen peroxide concentration of the aqueous hydrogen peroxide solution used, and the calculated hydrogen peroxide concentration in the air is downstream of the hydrogen peroxide vapor generator (31). The calculated value is accurate because it is obtained from the ratio of water to hydrogen peroxide in the aqueous hydrogen peroxide solution in the amount of water increase on the side. Therefore, variation in sterilization performance can be prevented by performing the sterilization operation by controlling the hydrogen peroxide vapor supplied to the treatment chamber (2) based on the above concentration.

  In addition, the air conditioner is controlled as the air supply / exhaust mechanism (60) to supply and exhaust air to the process chamber (2), while the hydrogen peroxide vapor generator (31) of the sterilizer (30) is used as the process chamber During the sterilization operation for supplying hydrogen peroxide vapor to (2), control is performed to maintain the hydrogen peroxide concentration at a predetermined value by the concentration determination means (52). Therefore, it becomes possible to stabilize the temperature and humidity of the processing chamber (2) during the sterilization operation. In particular, in the sterilization treatment using hydrogen peroxide, the sterilization effect is higher in the low humidity, whereas in the present embodiment, the inside of the treatment chamber (2) can be maintained at the low humidity. Therefore, the sterilization effect can be stabilized at a high level.

-Modification 1 of embodiment-
A first modification of the embodiment will be described. As shown in FIG. 7, the sterilization system (1) of the first modification is configured such that outside air is taken into the sterilizing gas generator (58) via the outside air processing air conditioner (13).

  Specifically, an outside air introduction passage (59) for connecting the air supply passage (11) and the sterilization gas generator (58) is provided. The outside air introduction passage (59) branches from the air supply passage (11) between the connection portion between the air supply passage (11) and the return passage (15) and the outside air processing air conditioner (13). In the sterilization operation, when the fifth sterilization gas switching valve (45e) is opened and the first air conditioning gas switching valve (56a) is closed, the air dehumidified by the outside air treatment air conditioner (13) is supplied to the sterilization gas generator ( 58).

  Also in this modified example, during the sterilization operation, the supply amount of hydrogen peroxide vapor to the processing chamber (2) and the concentration of hydrogen peroxide vapor downstream of the hydrogen peroxide vapor generator (31) While determining in (52), the apparatus is controlled by the controller (50) to adjust the hydrogen peroxide concentration in the processing chamber (2) to a predetermined value, which is the same as in the above embodiment.

-Modification 2 of embodiment-
A second modification of the embodiment will be described. As shown in FIG. 8, in the sterilization system (1) of the second modification, the main flow path (34) of the sterilization system side circuit (30) is connected to the air supply path (11) and the exhaust of the air conditioning system side circuit (10). It is connected directly to the processing chamber (2), not the passage (28).

  Also in this modified example, during the sterilization operation, the supply amount of hydrogen peroxide vapor to the processing chamber (2) and the concentration of hydrogen peroxide vapor downstream of the hydrogen peroxide vapor generator (31) While determining in (52), the apparatus is controlled by the controller (50) to adjust the hydrogen peroxide concentration in the processing chamber (2) to a predetermined value, which is the same as in the above embodiment.

—Modification 3 of Embodiment—
A modification 3 of the embodiment will be described. In Modification 3, although not shown, the sterilization system (1) is configured for a plurality of processing chambers (2). In this case, a damper (23, 24, 25) and a constant air volume device (22) are connected to the path branched from the air supply passage (11) and the exhaust passage (28) and connected to each processing chamber (2). Provide. Thereby, it becomes possible to perform the sterilization process of each process chamber (2) separately. Dampers (23, 24, 25) so that the air conditioned by the outside air treatment air conditioner (13) and the sensible heat air conditioner (17) through the steady operation flows into the processing chamber (2) that has not been sterilized. ) Adjust the constant air volume device (22).

  Also in this modified example, during the sterilization operation, the supply amount of hydrogen peroxide vapor to the processing chamber (2) and the concentration of hydrogen peroxide vapor downstream of the hydrogen peroxide vapor generator (31) While determining in (52), the apparatus is controlled by the controller (50) to adjust the hydrogen peroxide concentration in the processing chamber (2) to a predetermined value, which is the same as in the above embodiment.

-Modification 4 of the embodiment-
Modification 4 of the embodiment will be described. As shown in FIG. 9, in the fourth modification, the air conditioning system side circuit (10) is not provided, and the air conditioning process and the sterilization process of the processing chamber (2) are executed only by the sterilization system side circuit (30). It is configured as follows.

  In this sterilization system (1), in the preparatory operation, the sterilization gas generator (58) is controlled to stop the hydrogen peroxide vapor generator (31) and operate only the dehumidifier (57). As a result, the air taken from outside and dehumidified by the sterilization gas generator (58) is adjusted in temperature by the sterilization side air conditioner (53) and flows into the processing chamber (2), and the processing chamber (2) is targeted. Adjusted to humidity.

  Also in this modified example, during the sterilization operation, the supply amount of hydrogen peroxide vapor to the processing chamber (2) and the concentration of hydrogen peroxide vapor downstream of the hydrogen peroxide vapor generator (31) While determining in (52), the apparatus is controlled by the controller (50) to adjust the hydrogen peroxide concentration in the processing chamber (2) to a predetermined value, which is the same as in the above embodiment.

<< Other Embodiments >>
About the said embodiment, it is good also as the following structures.

  For example, in the above embodiment, the sterilization operation is a high concentration operation in which the concentration of hydrogen peroxide in the sterilization gas is about 500 ppm, but it is not always necessary to perform the high concentration sterilization operation every time sterilization is performed. When processing in a short time, such as at night, when the manufacturing room is not used, a preparatory operation, a sterilization operation with a low concentration of about 5 to 10 ppm, and a second dilution operation that ventilates the processing chamber (2) are performed. One dilution operation may be omitted.

  Moreover, in the said embodiment, as an upstream temperature / humidity sensor (31a) and a downstream temperature / humidity sensor (31b), an example using a relative hygrometer and a dry bulb thermometer, a dry bulb thermometer and a wet bulb thermometer, However, as long as the temperature and humidity can be detected on the upstream and downstream sides of the hydrogen peroxide generator (31), the measurement means may be changed as appropriate, and the same measurement may be performed on the upstream and downstream sides. There is no need to use means. For example, the measurement pattern includes a pattern for measuring dry bulb temperature and absolute humidity, a pattern for measuring dry bulb temperature and dew point temperature, and absolute humidity and relative humidity on the upstream side and downstream side of the hydrogen peroxide generator (31). You may select suitably from the pattern to measure, the pattern which measures wet-bulb temperature, and relative humidity.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.

  As described above, the present invention is useful for a sterilization system that sterilizes a processing chamber with hydrogen peroxide.

It is a piping system diagram of a sterilization system concerning an embodiment of the present invention. It is a figure which shows the operation | movement of a preparatory operation in the sterilization system of FIG. It is a figure which shows operation | movement of the sterilization driving | operation in the sterilization system of FIG. It is a figure which shows operation | movement of the 1st dilution driving | operation in the sterilization system of FIG. It is a figure which shows operation | movement of the 2nd dilution driving | operation in the sterilization system of FIG. It is a figure which shows operation | movement of steady operation in the sterilization system of FIG. It is a piping system diagram of a sterilization system concerning modification 1 of an embodiment of the present invention. It is a piping system diagram of a sterilization system concerning modification 2 of an embodiment of the present invention. It is a piping system diagram of a sterilization system concerning modification 4 of an embodiment of the present invention.

Explanation of symbols

1 Sterilization system
2 Processing chamber
10 Air conditioning system side circuit
30 Sterilization system side circuit (sterilization equipment)
31 Hydrogen peroxide vapor generator
31a Upstream temperature and humidity sensor (upstream temperature and humidity detection means)
31b Downstream temperature / humidity sensor (downstream temperature / humidity detection means)
33 Hydrogen peroxide generation flow path
50 controller (control means)
52 Concentration judgment unit (concentration judgment means)
52a Concentration calculator (concentration calculator)
60 Air supply / exhaust mechanism

Claims (6)

A sterilization apparatus provided with a hydrogen peroxide vapor generator (31) in a hydrogen peroxide generation flow path (33) through which air flows,
The upstream temperature / humidity detection means (31a) for detecting the temperature and humidity of the air upstream of the hydrogen peroxide vapor generator (31), and the temperature and humidity of the air downstream of the hydrogen peroxide vapor generator (31) Based on the temperature and humidity on the upstream and downstream sides of the hydrogen peroxide vapor generator (31), the hydrogen peroxide concentration in the downstream air is determined based on the downstream temperature and humidity detection means (31b) for detecting A sterilizer comprising a concentration determination means (52). In claim 1,
The concentration determination means (52) calculates the amount of water increase on the downstream side from the amount of water passing per unit time on the upstream and downstream sides of the hydrogen peroxide vapor generator (31) in the hydrogen peroxide generation flow path (33). Calculate and integrate the mass ratio to water based on the hydrogen peroxide concentration of the hydrogen peroxide solution used in the hydrogen peroxide vapor generator (31) to the amount of water increase. A sterilization apparatus comprising a concentration calculation unit (52a) for obtaining an amount and calculating a hydrogen peroxide concentration from the amount of hydrogen peroxide and the amount of passing air. In claim 1 or 2,
The upstream temperature / humidity detection means (31a) and the downstream temperature / humidity detection means (31b) include a relative hygrometer that measures the relative humidity of the air upstream and downstream of the hydrogen peroxide vapor generator (31), A sterilizer comprising a dry bulb thermometer for measuring a dry bulb temperature of air. In claim 1 or 2,
The upstream temperature / humidity detection means (31a) and the downstream temperature / humidity detection means (31b) are a dry bulb thermometer that measures the dry bulb temperature of the air upstream and downstream of the hydrogen peroxide vapor generator (31). And a wet bulb thermometer for measuring the wet bulb temperature of the air. Sterilization of supplying hydrogen peroxide vapor to the processing chamber (2) with a supply / exhaust mechanism (60) capable of supplying and exhausting air to the processing chamber (2) and a hydrogen peroxide vapor generator (31) A sterilization system comprising a device (30),
A sterilizer (30) is constituted by the sterilizer according to any one of claims 1 to 4,
During the sterilization operation in which hydrogen peroxide vapor is supplied from the hydrogen peroxide vapor generator (31) to the treatment chamber (2), the concentration determination means (52) of the sterilizer (30) allows the concentration of hydrogen peroxide in the air. A sterilization system comprising control means (50) for performing control to maintain the value at a predetermined value. In claim 5,
The sterilization system characterized in that the air supply / exhaust mechanism (60) is provided with an air conditioner that supplies air with adjusted temperature and humidity to the processing chamber (2).

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