JP5452997B2 - Indoor decontamination system - Google Patents

Description

  The present invention relates to an indoor decontamination system for decontaminating a decontamination target room such as a sterile pharmaceutical clean room.

For example, in a sterile product clean room, it is required to maintain an aseptic environment where the sterility assurance level (SAL) is 10 ⁻⁶ (1 million products, 1 or less non-sterile products). For this reason, decontamination is performed to reduce the number of spore bacteria that can grow to a specified level.

  On the other hand, formaldehyde (formaldehyde gas fumigation) was frequently used as a decontamination agent, but formaldehyde is a carcinogenic substance and is known to cause sick house even at low concentrations. (Management standard) regulates its use. On the other hand, hydrogen peroxide, ozone, chlorine dioxide, peracetic acid, etc. have been studied as alternative decontamination agents for formaldehyde. Among these, hydrogen peroxide is the temperature and humidity (20-25 ° C., 40-60%) of the clean room. ) Can be used (decontamination is possible), and humidification / dehumidification is unnecessary, and further, there are advantages in that there are few disadvantages compared to other decontamination agents and it is easy to handle. For this reason, in recent years, it has been proposed and put into practical use that hydrogen peroxide, which has been mainly used for decontamination of isolators and glove boxes, is applied to decontamination of clean rooms.

  When hydrogen peroxide is used as a decontamination agent, hydrogen peroxide is gasified by a hydrogen peroxide generator, and the hydrogen peroxide gas is circulated while being supplied into a clean room for decontamination. Then, when the decontamination is completed, the hydrogen peroxide in the inside air is decomposed while the inside air in the clean room is sucked by the hydrogen peroxide decomposition apparatus. That is, hydrogen is supplied and decomposed while circulating air between the clean room and the hydrogen peroxide generator or hydrogen peroxide decomposer. Moreover, in the application example to a clean room, it is often operated by a method in which hydrogen peroxide gas is directly discharged from the hydrogen peroxide generator into the clean room (see, for example, Patent Document 1).

JP 2008-1113727 A

  However, in the conventional indoor decontamination system using hydrogen peroxide as a decontamination agent, separate ducts are provided for the hydrogen peroxide release line and the hydrogen peroxide decomposition line in the circulation system during decontamination. Yes. That is, the hydrogen peroxide generator and the hydrogen peroxide decomposer are connected to the clean room by ducts provided individually. For this reason, there is a problem that it is necessary to secure a duct space and a cost for the duct is required.

  In the conventional indoor decontamination system, the duct (return duct, air supply duct) that returns the clean room interior air to the hydrogen peroxide generator or hydrogen peroxide decomposer is not insulated. Hydrogen condensation may occur. In particular, when condensation of hydrogen peroxide occurs in the return duct connected to the hydrogen peroxide generator, for example, to achieve the required indoor hydrogen peroxide concentration, the expected hydrogen peroxide is calculated assuming no condensation. Approximately 5 times the amount of hydrogen peroxide that is actually input is required.

  In view of the above circumstances, the present invention firstly reduces the amount of ducts to minimize the space and costs, and secondly, achieves a desired decontamination performance with a small amount of hydrogen peroxide input. An object of the present invention is to provide an indoor decontamination system capable of exerting and improving the decontamination performance.

  In order to achieve the above object, the present invention provides the following means.

The indoor decontamination system of the present invention is an indoor decontamination system for decontaminating a decontamination target chamber using hydrogen peroxide, and includes an outlet provided in the decontamination target chamber and the decontamination target chamber An air supply duct that connects an external air conditioner disposed outside the air supply duct, a first on-off valve that is provided in the air supply duct and opens and closes the air supply duct, and a suction port that is provided in the decontamination target chamber And a return air duct connecting the exhaust fan disposed outside the chamber to be decontaminated, a second on-off valve provided in the return air duct for opening and closing the return air duct, and one end of the supply duct A communication duct having the other end connected between the second on-off valve of the return air duct and the suction port, and a first connected to the communication duct . It is placed between the air supply duct and the first exhaust duct, and hydrogen peroxide solution is vaporized and peroxidized. A hydrogen peroxide generator for generating elementary gas and a second air supply duct and a second exhaust duct connected to the communication duct, and a hydrogen peroxide generator that decomposes hydrogen peroxide contained in the air. A hydrogen oxide cracking device, a third on-off valve provided between each connection part of the second air supply duct and the second exhaust duct of the communication duct, the first exhaust duct, A fourth on-off valve that opens and closes one exhaust duct; a fifth on-off valve that opens and closes the first air supply duct; and a second on-off valve that opens and closes the first air supply duct, and the second air supply duct. A sixth on-off valve for opening and closing the air supply duct , wherein the hydrogen peroxide generating device and the hydrogen peroxide decomposing device are arranged in series along the communication duct, and the hydrogen peroxide gas is removed. during injection operation for injecting the dye the target chamber, said first opening Closes the valve and the second on-off valve and the sixth on-off valve, the third opening and closing valve and the 4-off valve is opened the fifth on-off valve, the hydrogen peroxide gas generated by the hydrogen peroxide generator Air containing the hydrogen peroxide generator from the first exhaust duct, the first exhaust duct to the communication duct, the communication duct to the air supply duct, the air supply duct to the decontamination target chamber, the decontamination The return air duct from the dyeing target chamber, the communication duct from the return air duct, the first supply air duct from the communication duct, the circulation from the first air supply duct to the hydrogen peroxide generator, During the decomposition operation for decomposing hydrogen peroxide gas, the first on-off valve, the second on-off valve, the third on-off valve, the fourth on-off valve, and the fifth on-off valve are closed, and the sixth on-off valve is opened. Open the hydrogen peroxide gas Air containing hydrogen gas from the hydrogen peroxide decomposition device, the second exhaust duct, the communication duct, the communication duct, the supply duct, the supply duct, the decontamination chamber, Circulating and circulating the return air duct from the decontamination target chamber, the return air duct to the communication duct, the communication duct to the second air supply duct, and the second air supply duct to the hydrogen peroxide decomposition apparatus. It is comprised by these.

In the present invention, the air in the decontamination target chamber is sucked in from the air supply duct for supplying air to the air outlet provided in the decontamination target chamber and the suction port provided in the decontamination target chamber, and is supplied to the outside. A hydrogen peroxide generator and a hydrogen peroxide decomposer are placed in series along the connecting duct connecting the return air duct for the discharge line (air containing hydrogen peroxide gas circulates and circulates during the injection operation). Line) and the decomposition line ( the line through which the air containing hydrogen peroxide gas circulates and circulates during the decomposition operation) is configured using the same connecting duct , so separate ducts are provided for the discharge line and the decomposition line. Compared with the conventional indoor decontamination system provided, the amount of ducts can be reduced.

Furthermore, in the indoor decontamination system of the present invention , a heat insulating material is wound around the communication duct, the first air supply duct, the second air supply duct, and the return air duct so as to be insulated. More preferably, the connecting duct, the first air supply duct, the second air supply duct, and the return air duct that are wound with the heat insulating material are heated before decontamination. .

  In this invention, before decontamination, that is, before supplying hydrogen peroxide, the inside of the duct for returning air from the decontamination target chamber to the hydrogen peroxide generator and / or the hydrogen peroxide decomposer is heated. Thus, the temperature in the heat-insulated duct can be increased and maintained. Thereby, even if it is a case where the air containing hydrogen peroxide circulates in a discharge line or a decomposition line, it can prevent dew condensation generating in a duct. Therefore, compared with the conventional indoor decontamination system, the amount of hydrogen peroxide input for achieving the required indoor hydrogen peroxide concentration can be reduced, and the decontamination performance can be improved.

According to the indoor decontamination system of the present invention, the hydrogen peroxide generator and the hydrogen peroxide decomposition device are arranged in series along the communication duct, and the discharge line and the decomposition line are configured using the same communication duct. Therefore, the amount of ducts can be reduced as compared with a conventional indoor decontamination system in which separate ducts are provided in the discharge line and the decomposition line, respectively. As a result, the amount of ducts can be minimized to save space and cost, and it is possible to perform decontamination efficiently and reliably.

It is a figure which shows the indoor decontamination system which concerns on one Embodiment of this invention. It is a figure which shows the state at the time of normal air-conditioning driving | operation of the indoor decontamination system which concerns on one Embodiment of this invention. It is a figure which shows the state at the time of the injection | pouring operation | movement of the indoor decontamination system which concerns on one Embodiment of this invention. It is a figure which shows the state at the time of the holding | maintenance driving | operation of the indoor decontamination system which concerns on one Embodiment of this invention. It is a figure showing the state at the time of decomposition operation (aeration decomposition operation) of the indoor decontamination system concerning one embodiment of the present invention. It is a figure which shows the state at the time of the external air introduction operation | movement of the indoor decontamination system which concerns on one Embodiment of this invention. It is a figure which shows the clean room and BI installation location used by description (Example) of verification experiment. It is a figure which shows the result of a demonstration experiment.

  Hereinafter, an indoor decontamination system according to an embodiment of the present invention will be described with reference to FIGS. The present embodiment relates to an indoor decontamination system that supplies hydrogen peroxide into a sterile pharmaceutical clean room for decontamination.

  A clean room (decontamination target room) 1 according to the present embodiment includes a conventionally known air conditioning system A as shown in FIG. This air conditioning system A is provided in the clean room 1 and has an air outlet 3 and a suction port 4 in which a HEPA filter 2 is installed, an air supply duct 6 connected to the air outlet 3 and an external air conditioner 5 outside the clean room 1, A return air duct 8 connected to the suction port 4 and the exhaust fan 7 outside the clean room 1 is provided. The air supply duct 6 and the return air duct 8 are provided with on-off valves (first on-off valve 9 and second on-off valve 10), respectively.

  According to the air conditioning system A of the clean room 1, when the external air conditioner 5 is driven with the first on-off valve 9 opened, the outside air is supplied to the outlet 3 through the air supply duct 6, and the HEPA filter 2 is turned on. It passes through and is supplied into the clean room 1 from the outlet 3. When the exhaust fan 7 is driven with the second on-off valve 10 opened, the air (return air) in the clean room 1 is sent to the outside through the return air duct 8 and sent to the external air conditioner 5. At this time, part of the air sent to the outside through the return air duct 8 is exhausted to the outside. Thereby, at the time of the normal air-conditioning operation by the air-conditioning system A, as shown in FIG. 2, the purified air is circulated and circulated in the clean air-conditioning line S1.

  On the other hand, the indoor decontamination system B of the present embodiment is a system for decontaminating a clean room using hydrogen peroxide as a decontamination agent. As shown in FIG. A disassembly device 12 is provided. For example, the hydrogen peroxide generator 11 sucks the hydrogen peroxide solution from the tank that stores the hydrogen peroxide solution as the water pump is driven, and drops the hydrogen peroxide solution onto the heating surface to cause flash evaporation. It is configured to generate hydrogen peroxide gas (hydrogen peroxide vapor). The hydrogen peroxide decomposition apparatus 12 includes a platinum catalyst as a catalyst, and is configured to decompose and remove hydrogen peroxide from air containing hydrogen peroxide gas with the platinum catalyst.

Further, in the indoor decontamination system B of the present embodiment, a communication duct 15 is constructed so as to be connected to the air supply duct 6 and the return air duct 8 of the air conditioning system A. The communication duct 15 is provided with one end connected between the first opening / closing valve 9 and the outlet 3 of the air supply duct 6 and the other end connected between the second opening / closing valve 10 of the return air duct 8 and the suction port 4. It has been. That is, the circulation duct part and contact duct 15 some return air duct 8 of the air supply duct 6 is formed.

  The hydrogen peroxide generator 11 is connected to the communication duct 15 via a first exhaust duct 16 and a first air supply duct 17. Further, the hydrogen peroxide decomposing apparatus 12 is connected to the communication duct 15 via the second exhaust duct 18 and the second air supply duct 19. Further, the communication duct 15 is provided with a circulation fan 20 between the connection portions of the first exhaust duct 16 and the first air supply duct 17, and the second exhaust duct 18 and the second exhaust duct 18 of the hydrogen peroxide decomposition device 12 are provided. A third on-off valve (switching mechanism) 21 is provided between each connection portion of the air supply duct 19.

  In addition, a fourth open / close valve (switching mechanism) 22 and a fifth open / close valve (switching mechanism) 23 are respectively provided in the first exhaust duct 16 and the first air supply duct 17 that connect the hydrogen peroxide generator 11 and the communication duct 15. A sixth on-off valve (switching mechanism) 24 is provided in the second air supply duct 19 that is provided and connects the hydrogen peroxide decomposition apparatus 12 and the communication duct 15.

  Further, in this embodiment, a heat insulating material such as glass wool is wound around the outside of the communication duct 15, the first air supply duct 17, the second air supply duct 19, and the return air duct 8, and these ducts 15, 17, 19 are wound. , 8 are heat-insulated.

  And when performing the decontamination operation | work of the clean room 1 with the indoor decontamination system B of this embodiment which consists of the said structure, injection | pouring operation is performed first. When switching from the normal air-conditioning operation to the injection operation, the first on-off valve 9 and the second on-off valve 10 of the air-conditioning system A are closed, the third on-off valve 21, the fourth on-off valve 22, and the fifth on-off valve 23 are opened. The circulation fan 20 is driven. Accordingly, as shown in FIG. 3, by driving the circulation fan 20, the first exhaust duct 16 to the communication duct 15, the communication duct 15 to the air supply duct 6, and the air supply duct 6 to the clean room 1 are driven by the hydrogen peroxide generator 11. Air flows from the clean room 1 to the return air duct 8, from the return air duct 8 to the connecting duct 15, and from the connecting duct 15 to the first air supply duct 17 of the hydrogen peroxide generator 11 and circulates. The air conditioning line S1 is switched to the discharge line S2 during the injection operation.

  Moreover, in this embodiment, while switching from the normal air conditioning line S1 to the discharge line S2 (before decontamination), the inside of the ducts 15, 17, 19, and 8 subjected to the heat insulation treatment is heated.

  At the stage of switching to the discharge line S2, the hydrogen peroxide generator 11 is driven, and the hydrogen peroxide gas generated by the hydrogen peroxide generator 11 is released to the discharge line S2. As a result, air containing hydrogen peroxide gas circulates through the discharge line S2, and the hydrogen peroxide gas is supplied to the clean room 1. The driving of the hydrogen peroxide generator 11 is stopped when a predetermined amount of hydrogen peroxide is charged from the hydrogen peroxide generator 11. In this embodiment, the ducts 15, 17, 19, and 8 are heat-insulated, and the inside of the ducts 15, 17, 19, and 8 is heated, so that the hydrogen peroxide gas is discharged from the discharge line S2. When air containing air circulates, hydrogen peroxide does not condense in the ducts 15, 17, 19, 8. For this reason, compared with the conventional indoor decontamination system, the amount of hydrogen peroxide input can be reduced.

  In addition, the holding operation is performed at the stage where a predetermined amount of hydrogen peroxide is charged by the injection operation. In this holding operation, as shown in FIG. 4, the fourth on-off valve 22 and the fifth on-off valve 23 are closed, and overoxidation occurs in the discharge line S 2 ′ of the communication duct 15, the air supply duct 6, the clean room 1, and the return air duct 8. Circulate air containing hydrogen gas. As a result, air containing hydrogen peroxide of a predetermined concentration is reliably supplied to the clean room 1, the spore bacteria that can grow in the clean room 1 are killed, and the clean room 1 is decontaminated. At this time, not only the clean room 1 but also the air containing the hydrogen peroxide gas circulates and circulates not only in the air supply system 6 but also in the air supply duct 6, the air outlet 3 and the air inlet 4, the HEPA filter 2, and the return air duct 8. Therefore, the entire circulation system of the discharge lines S <b> 2 and S <b> 2 ′ including the communication duct 15 and the circulation fan 20 is decontaminated at the same time as the clean room 1 is decontaminated. Furthermore, hydrogen peroxide gas is uniformly supplied into the clean room 1 by supplying the hydrogen peroxide gas to the clean room 1 using the air conditioning system A (the air outlet 3, the suction port 4, etc.). For this reason, the inside of the clean room 1 is decontaminated suitably and reliably.

  Next, the decomposition operation is performed when the decontamination of the clean room 1 is completed. In this disassembly operation (aeration disassembly), the third on-off valve 21 is closed and the sixth on-off valve 24 is opened. As a result, as shown in FIG. 5, the second exhaust duct 18 of the hydrogen peroxide decomposition apparatus 12 is connected to the communication duct 15, the communication duct 15 is supplied to the supply duct 6, the supply duct 6 is connected to the clean room 1, and the clean room 1 is returned to the return duct. 8. Air containing hydrogen peroxide gas circulates and circulates from the return air duct 8 to the connecting duct 15 and from the connecting duct 15 to the second air supply duct 19 of the hydrogen peroxide decomposing apparatus 12, and the discharge line S2 during the holding operation. 'Is switched to the disassembly line S3 during the disassembly operation.

  By switching to the decomposition line S3 in this way, air containing hydrogen peroxide gas is sequentially introduced from the clean room 1 to the hydrogen peroxide decomposition apparatus 12, and the hydrogen peroxide decomposition apparatus 12 decomposes and attenuates hydrogen peroxide. This decomposition operation is performed until the hydrogen peroxide in the circulating air reaches a safe concentration level (for example, 1 ppm or less). In the hydrogen peroxide decomposition apparatus 12 of the present embodiment, a platinum catalyst is used as a catalyst for decomposing hydrogen peroxide, but other catalysts can also be used. Candidates include metals such as manganese dioxide, nickel and copper, enzymes and activated carbon.

Next, the outside air introduction operation is performed when hydrogen peroxide in the air is decomposed to a safe concentration level by the decomposition operation. In this outside air introduction operation, the sixth on-off valve 24 is closed and the driving of the circulation fan 20 is stopped. At the same time, the first on-off valve 9 and the second on-off valve 10 are opened to drive the external air conditioner 5. As a result, as shown in FIG. 6, the purified air flows in the clean room 1 through the outside air introduction line S1 ′ similar to the normal air conditioning line S1, and in a low concentration region where the decay rate of the hydrogen peroxide concentration decreases. By switching to the outside air introduction operation, the reduction of the hydrogen peroxide concentration in the clean room 1 is promoted. During the outside air introduction operation, all the air discharged from the clean room 1 through the return air duct 8 is exhausted to the outside. In addition, the outside air introduction operation may be selectively performed as appropriate at the user's discretion.

  Then, the decontamination work of the clean room 1 is completed by performing the injection operation, the holding operation, the decomposition operation, and the outside air introduction operation from the normal air conditioning operation as described above. At this time, the air-conditioning system A and the indoor decontamination system B may be integratedly controlled to automate a series of decontamination operations of the injection operation, the holding operation, and the decomposition operation. Further, in this case, switching to the decontamination fully automatic operation may be operated with the air conditioning control panel touch panel. When automating a series of decontamination operations in this way, the outside air introduction operation may be performed manually.

  Here, a demonstration experiment in which the clean room 1 is decontaminated by the indoor decontamination system B according to the present embodiment will be described.

The clean room 1 in this demonstration experiment is a biological clean room with a room volume of about 51m ³ (2.7m x 7.0m x 2.7m (W x D x H)) and decontamination including equipment such as ducts. The internal volume of the time circulation system is about 53 m ³ .

  Moreover, the hydrogen peroxide generator 11 uses HYDEC 2100 manufactured by Kabuya Industry Co., Ltd., and the hydrogen peroxide decomposer 12 uses an apparatus that decomposes hydrogen peroxide with a platinum catalyst.

Also, hydrogen peroxide (H ₂ O ₂ ) is used for 35% weight concentration and less electronic stabilizer, the hydrogen peroxide generator 11 injection speed is set to 20 g / min, and the blowing rate is set to 40 m ³ / h. did. The experimental parameters are examined in four items: injection amount (hydrogen peroxide input amount), holding time, circulation air volume, and initial relative humidity.

  Here, in the definition of BI (biological indicator), the most resistant bacterium (the strongest bacterium that is most likely to survive) is used for the target sterilization method, and VPHP (hydrogen peroxide vapor) is used. In some cases, Geobacillus stearothermophilus spores with stainless steel support are used as BI. For this reason, in this demonstration experiment, what used inoculated Geobacillus stearothermophilus ATCC12980 spore made from Apex Laboratories on the stainless steel disc support | carrier was used for BI. The BI is contained in a small bag (28 mm × 64 mm) made of high-density polyethylene tyvek. As shown in FIG. 1 and FIG. 7, the BI is on the table 25 (BI-1) where decontamination is expected to be easy and on the floor (BI-1) below the table 25 where decontamination is expected to be difficult. -2), on the floor that is not directly under the outlet 3 (on the floor surface equidistant from the four outlets 3) (BI-3), and on the corner floor (BI-4).

  Here, the hydrogen peroxide concentration is measured by simultaneous multipoint measurement of the concentration in each part of the decontamination circulation system. The hydrogen peroxide collected in the pure water impinger is oxidized using potassium permanganate. The concentration was determined by titration. Moreover, the collection time to this impinger was the time of temperature increase, injection, and holding (about 1 hour), and the suction flow rate was 1 L / min. Further, the concentration change with time was measured with a hydrogen peroxide concentration sensor (Polytron 7000, manufactured by Dräger, 13 × 13 × 16 cm).

The BI test results of this example are shown in Table 1. Experiment No. 1 to 3, the input amount is constant at 400 g, and the initial relative humidity is changed. As a result, it was confirmed that the reached concentration (the highest concentration in the room) decreases as the initial relative humidity increases. As this factor , it is conceivable that a decrease in the concentration due to the dew condensation of hydrogen peroxide on the inner surface of the duct and the like, and a decrease in the concentration due to the dew condensation of water vapor easily occur. Since the dew point temperature of hydrogen peroxide is higher than the dew point temperature of water vapor, it is considered that the dew point of hydrogen peroxide occurs before the dew point of water vapor. In addition, Experiment No. In all cases 1 to 3, BI of the table floor (BI-2) was positive. This is presumably because the airflow is difficult to reach.

  Next, Experiment No. In 4-7, the effect of the input amount and the holding time was examined. As a result, when 500 g was added, even if the holding time was 20 minutes (even if it was shorter than 30 minutes in Experiments Nos. 1 to 3), BI was all negative. In addition, Experiment No. Even when 400 g was added at 6 and the holding time was 40 minutes, all BIs were negative.

  On the other hand, Experiment No. When 300 g was added in 7 and the holding time was 60 minutes, BI was positive in two places. From this, it was confirmed that the input amount has a greater influence on the decontamination effect than the retention time.

  Next, Experiment No. In Nos. 8 to 12, the circulating air flow was changed under the conditions where the input amount was 500 g and the holding time was 20 minutes. As a result, it was confirmed that BI was all negative regardless of the amount of circulating air.

  FIG. 8 shows the experiment No. 1 with good results. 4 and Experiment No. 5 shows the change over time in the hydrogen peroxide concentration measured by the hydrogen peroxide concentration sensor for the entire time zone including the aeration (decomposition operation) in FIG. The change with time in the hydrogen peroxide concentration is measured at two locations, the air outlet 3 and the air inlet 4.

  From this result, at the time of injection / holding, it can be confirmed that the concentration of the air outlet 3 and the air inlet 4 is almost equal, the system B is operating smoothly, and there is almost no decomposition of hydrogen peroxide in the room. . Further, at the time of aeration decomposition, the concentration at the outlet 3 from which the circulating air (return air) decomposed by the platinum catalyst filter is abruptly decreased, but the concentration at the inlet 4 was gradually decreased. This is because the air entering the suction port 4 includes hydrogen peroxide residue (condensation and adsorption) re-released from the indoor surface in addition to hydrogen peroxide accumulated in the room air. It is believed that there is.

  From the above results, it was proved that the decontamination and decomposition of hydrogen peroxide worked smoothly, and that the system can be fully deployed to the facility even in the present situation. In addition, among the four parameters studied, it was proved that the input amount of hydrogen peroxide solution (35%) had the most influence on decontamination. Furthermore, when the indoor relative humidity was high, the hydrogen peroxide concentration in the room tended to decrease, and it was confirmed that water vapor condensation on the inner surface of the duct and the hydrogen peroxide condensation on the indoor surface had an effect.

Therefore, in the indoor decontamination system B of the present embodiment, the hydrogen peroxide generator 11 and the hydrogen peroxide decomposition device 12 are connected in series via the switching mechanisms 22, 23, and 24 along the circulation duct (communication duct 15). Since the discharge line S2 (S2 ') and the decomposition line S3 are configured using the same circulation duct (the communication duct 15, the air supply duct 6 and the return air duct 8 of the air conditioning system A), the discharge line S2 (S2') Compared to a conventional indoor decontamination system in which separate ducts are provided in the line S2 and the decomposition line S3, the amount of ducts can be reduced. As a result, the amount of ducts can be minimized to save space and cost, and efficient and reliable decontamination can be achieved.

  Further, by using the ducts of the building air conditioning system A (the air supply duct 6 and the return air duct 8) as the circulation duct, the air outlet 3 and the suction provided in the clean room (decontamination target room) 1 of the air conditioning system A are used. Utilizing the mouth 4, it becomes possible to uniformly supply hydrogen peroxide to the clean room 1. Furthermore, by using the ducts 6 and 8 of the air conditioning system A as circulation ducts in this way, not only the clean room 1 but also the ducts 6 and 8 of the air conditioning system A, the circulation fan 20, the outlet 3, and the inlet 4 are provided. The entire circulation system such as the HEPA filter 2 can be decontaminated. This makes it possible to perform decontamination efficiently and reliably.

  Further, before decontamination, that is, before supplying hydrogen peroxide, the inside of the ducts 15, 17, 19, 8 for returning air from the clean room 1 to the hydrogen peroxide generator 11 and / or the hydrogen peroxide decomposer 12 is added. By keeping warm, the temperature in the heat-insulated ducts 15, 17, 19, and 8 can be raised and maintained. Thereby, even if it is a case where the air containing hydrogen peroxide circulates in discharge line S2 or decomposition line S3, it can prevent that condensation occurs in ducts 15, 17, 19, and 8. Therefore, compared with the conventional indoor decontamination system, the amount of hydrogen peroxide input for achieving the required indoor hydrogen peroxide concentration can be reduced, and the decontamination performance can be improved.

  As mentioned above, although one Embodiment of the indoor decontamination system of the building which concerns on this invention was described, this invention is not limited to said one Embodiment, In the range which does not deviate from the meaning, it can change suitably. For example, in the present embodiment, the decontamination target room has been described as being an aseptic preparation clean room, but the indoor decontamination system of the present invention may be applied to other clean rooms.

  The building indoor decontamination system according to the present invention can also control the hydrogen peroxide generator 11 and the hydrogen peroxide decomposer 12 in conjunction with various sensors. Therefore, the indoor decontamination system may be optimally operated by reflecting the values of various physical quantities sensed by various sensors. In this case, a dew condensation sensor, a temperature / humidity sensor, a hydrogen peroxide sensor, a differential pressure sensor, or the like can be applied as the sensor, and it is particularly effective to use a dew condensation sensor.

  Specifically, a certain degree of condensation of hydrogen peroxide is effective for decontamination, and this is generally called “microcondensation theory”. And since the vapor pressure of hydrogen peroxide is lower than the vapor pressure of water, that is, the dew point temperature of hydrogen peroxide is higher than the dew point temperature of water vapor, the dew point of hydrogen peroxide is considered to occur before the dew point of water vapor. It is done. For example, the saturated vapor pressure of 35 wt% (30 ° C.) hydrogen peroxide water is 23 mmHg, the hydrogen peroxide partial pressure at that time is 0.36 mmHg, and the water pressure is 22.64 mmHg. The saturated vapor pressure of only water (30 ° C.) is 32 mmHg. For this reason, hydrogen peroxide also naturally condenses under temperature and humidity conditions where water condenses. On the other hand, excessive dew condensation of hydrogen peroxide is a waste of chemical solution (hydrogen peroxide aqueous solution), and the corrosion load on the decontamination system (indoor interior materials, equipment, circulation ducts, etc.) becomes large. Considering the above, in the circulation system at the time of decontamination, hydrogen peroxide is condensed so that it does not become excessive, and water is not condensed, so that the condensation of hydrogen peroxide is effectively used for decontamination. It becomes possible.

  In the indoor decontamination system for buildings according to the present invention, the temperature / humidity of the circulating air and the indoor surface / inner surface of the circulation duct are sensed by a dew condensation sensor, a temperature / humidity sensor, a hydrogen peroxide sensor, a differential pressure sensor, etc. The result is fed back to the air-conditioning control, condensation is performed so that hydrogen peroxide does not become excessive, and temperature and humidity control of the circulating air and heating in the circulation duct are appropriately performed so as not to condense water. It becomes possible to effectively utilize the condensation of hydrogen oxide for decontamination.

1 Clean room (Decontamination target room)
2 HEPA filter 3 Air outlet 4 Suction port 5 Air conditioner 6 Air supply duct 7 Exhaust fan 8 Return air duct 9 First on-off valve 10 Second on-off valve 11 Hydrogen peroxide generator 12 Hydrogen peroxide decomposer 15 Communication duct 16 First exhaust duct 17 First supply duct 18 Second exhaust duct 19 Second supply duct 20 Circulating fan 21 Third on-off valve (switching mechanism)
22 4th on-off valve (switching mechanism)
23 Fifth open / close valve (switching mechanism)
24 6th on-off valve (switching mechanism)
25 Table A Air conditioning system B Indoor decontamination system S1 Normal air conditioning line S2 Release line S2 'Release line S3 Disassembly line
S1 ' outside air introduction line

Claims (2)

An indoor decontamination system for decontaminating a decontamination target room using hydrogen peroxide,
An air supply duct that connects an outlet provided in the decontamination target chamber and an external air conditioner disposed outside the decontamination target chamber;
A first on-off valve provided in the air supply duct for opening and closing the air supply duct;
A return air duct that connects a suction port provided in the decontamination target chamber and an exhaust fan disposed outside the decontamination target chamber;
A second on-off valve provided in the return air duct for opening and closing the return air duct;
A communication duct having one end connected between the first on-off valve of the air supply duct and the outlet and the other end connected between the second on-off valve of the return air duct and the suction port;
A hydrogen peroxide generator disposed between the first air supply duct and the first exhaust duct connected to the communication duct and generating hydrogen peroxide gas by vaporizing hydrogen peroxide water;
A hydrogen peroxide decomposition apparatus that is disposed between the second air supply duct and the second exhaust duct connected to the communication duct and decomposes hydrogen peroxide contained in the air;
A third on-off valve provided between each connection portion of the second air supply duct and the second exhaust duct of the communication duct;
A fourth on-off valve provided in the first exhaust duct for opening and closing the first exhaust duct;
A fifth on-off valve provided in the first air supply duct for opening and closing the first air supply duct;
A sixth on-off valve provided in the second air supply duct for opening and closing the second air supply duct ;
The hydrogen peroxide generating device and the hydrogen peroxide decomposing device are arranged in series along the communication duct,
During the injection operation of injecting the hydrogen peroxide gas into the decontamination target chamber, the first on-off valve, the second on-off valve, and the sixth on-off valve are closed, and the third on-off valve, the fourth on-off valve, Open the fifth on-off valve;
Air containing hydrogen peroxide gas generated by the hydrogen peroxide generator is supplied from the hydrogen peroxide generator to the first exhaust duct, from the first exhaust duct to the communication duct, and from the communication duct to the air supply duct. From the air supply duct to the decontamination target chamber, from the decontamination target chamber to the return air duct, from the return air duct to the communication duct, from the communication duct to the first air supply duct, from the first air supply duct Circulate and circulate through the hydrogen peroxide generator,
During the decomposition operation for decomposing the hydrogen peroxide gas, the first on-off valve, the second on-off valve, the third on-off valve, the fourth on-off valve, and the fifth on-off valve are closed, and the sixth on-off valve Open
The air containing the hydrogen peroxide gas, the from the hydrogen peroxide decomposition device a second exhaust duct, the contact duct from said second exhaust duct, the air supply duct from the communication duct, the decontamination from the air supply duct The target chamber, the return air duct from the decontamination target chamber, the communication duct from the return air duct, the second air supply duct from the communication duct, and the hydrogen supply decomposition device from the second air supply duct. An indoor decontamination system characterized by being configured to circulate. The indoor decontamination system according to claim 1,
A heat insulating material is wound around the outside of the connecting duct, the first air supply duct, the second air supply duct, and the return air duct, and heat treatment is performed.
Before the decontamination, the connecting duct, the first air supply duct, the second air supply duct, and the return air duct around which the heat insulating material is wound are configured to be heated. Indoor decontamination system.

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