JP2019088390A - Sterilization method and sterilization device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sterilization method and a sterilization device for efficiently sterilizing a space with an appropriate humidity. SOLUTION: Water is supplied to a two-fluid nozzle N1 to N5 from a water supply pipe 45 connected to a fluid supply pipe 41 connected to the two-fluid nozzle N1 to N5 via a valve 47, and the two-fluid nozzle is provided. The room is humidified by spraying water from N1 to N5. Further, the chemical solution is supplied to the two-fluid nozzles N1 to N5 from the chemical solution supply pipe 46 connected to the fluid supply pipe 41, and the chemical solution is sprayed from the two-fluid nozzles N1 to N5 to sterilize the room. After spraying the chemical solution, the spraying of the chemical solution is stopped, a holding process for maintaining the state is executed, and a purge process for discharging the chemical solution remaining in the fluid supply pipe 41 is executed. [Selection diagram] Fig. 1

Description

  The present invention relates to a sterilization method and a sterilization apparatus for humidifying and sterilizing.

  It is being studied to disinfect bacteria by spraying chemicals such as hypochlorous acid aqueous solution which has a sterilizing effect inside food manufacturing facilities such as food factories and facilities of medical and welfare facilities (for example, Patent Document 1) reference). This Patent Document 1 describes that sterilization can be performed by spraying a chemical solution from a two-fluid nozzle into an indoor space so that the relative humidity after spraying is 70% or more. Furthermore, when relative humidity of the indoor space before spraying is low, it is described that the chemical solution is sprayed after being humidified by a humidifier.

JP, 2016-27849, A

  However, in the technique described in Patent Document 1, it is necessary to spray a large amount of chemical solution in chemical solution spraying from low humidity, and as a result, there is a concern about the influence of corrosion of building materials and the like. For this reason, it is necessary to install a humidifier separately from the sterilization equipment, which requires cost and time for installation.

  The sterilization method for solving the above-mentioned problems is connected to a liquid supply pipe to which a chemical solution used for sterilization is supplied, and the inside of the space is disinfected using a two-fluid nozzle that sprays the chemical solution using gas. In the method, a humidifying liquid is supplied to the two-fluid nozzle from a humidifying liquid supply pipe connected to the liquid supply pipe via a switching valve, and the humidifying liquid is sprayed to humidify the space. Performing the humidifying stage, and the sterilizing stage of sterilizing the space by supplying the chemical solution to the two-fluid nozzle from a chemical solution supply pipe connected to the liquid supply pipe via the switching valve. .

  ADVANTAGE OF THE INVENTION According to this invention, space can be made into appropriate humidity and it can disinfect efficiently.

The piping diagram explaining the structure of the sterilization apparatus in this embodiment. Explanatory drawing explaining the structure in the space of the sterilization object in this embodiment. The block diagram explaining the composition of the control unit in this embodiment. The graph which illustrates the relation between relative humidity and the time from the start of spraying and relative humidity in the sterilization apparatus of the present embodiment. Explanatory drawing explaining the disinfection conditions in this embodiment. The flowchart of the process sequence explaining the sterilization method in this embodiment. It is explanatory drawing explaining the flow of the gas and the liquid in the sterilization apparatus of this embodiment, Comprising: (a) is humidification control processing, (b) shows chemical | medical solution spray processing, (c) shows purge processing.

Hereinafter, an embodiment in which the sterilization apparatus and the sterilization method are embodied will be described using FIGS. 1 to 7.
First, the configuration of the sterilization apparatus 30 provided with the two-fluid nozzles N1 to N5 will be described with reference to FIG.

  The sterilization apparatus 30 includes a plurality of two-fluid nozzles N1 to N5, a compressor C1, an air tank Ta1, and a chemical liquid tank Tc1. A drug solution used for sterilization of a room is stored in the drug solution tank Tc1. As this chemical solution, a chemical solution having a pH of 6.5 and a hypochlorous acid concentration of 120 mg / L is used. This solution is prepared by diluting sodium hypochlorite 6% with tap water and then adjusting the pH by adding 3% hydrochloric acid as a food additive. Purex (registered trademark) S was used as sodium hypochlorite 6%. In addition, tap water: Purex S: salt additive 3% hydrochloric acid was mixed in a ratio of 650: 1: 1.

  The sterilization apparatus 30 includes gas supply pipes 31 and 35, a gas supply valve 36, a fluid supply pipe 41 as a liquid supply pipe, a gas liquid switching valve 43, a connection pipe 44, a water supply pipe 45, a chemical liquid supply pipe 46, and a valve 47. , 48, and a drain valve 49 for discharging the chemical solution to a bucket or the like. Two fluid nozzles N1 to N5 are connected to the downstream side of the gas supply pipe 31 and the fluid supply pipe 41, respectively.

  The two-fluid nozzle N1 to N5 sprays the liquid in the form of a spray using compressed air. The two-fluid nozzles N1 to N5 each have a compressed air intake portion and a liquid intake portion, mix the air and the liquid, and spray an atomized liquid from the spray port. In the present embodiment, a two-fluid siphon spray nozzle is used as the two-fluid nozzle. Specifically, Quick Fogger (trade name) manufactured by Spraying Systems Japan Ltd. is used. In addition, the amount of spray liquid per time of the two-fluid nozzles N1 to N5 can be controlled by the air pressure of the compressed air supplied. In the present embodiment, a spray port with a mist particle diameter of 9 μm is used. A gas supply pipe 31 for supplying compressed air and a fluid supply pipe 41 for supplying a liquid to be sprayed are connected to the intakes of the two-fluid nozzles N1 to N5.

  On the downstream side of the gas supply pipe 31, air supply valves V1 to V5 and a ball valve are respectively provided corresponding to the two-fluid nozzles N1 to N5. Each of the air supply valves V1 to V5 is a three-way solenoid valve, and the external opening on the two fluid nozzles N1 to N5 side at the time of non-energization, the gas supply pipe 31 at the time of energization, and the respective two fluid nozzles N1 to N5 Switch between connection and

  The upstream side of the gas supply pipe 31 is connected to the air tank Ta1 via a pressure reducing valve, a mist separator and a ball valve. The air tank Ta1 is connected to the compressor C1 via a ball valve, and supplies compressed air to the gas supply pipe 31 by the pressure from the compressor C1.

  The gas supply pipe 31 is connected to the gas supply pipe 35 via a pressure reducing valve. The gas supply pipe 35 is supplied to the chemical solution tank Tc1 via the gas supply valve 36. The gas supply pipe 35 is connected to the fluid supply pipe 41 via the gas liquid switching valve 43.

On the other hand, the fluid supply pipe 41 is connected to the connection pipe 44 via the gas liquid switching valve 43.
The gas liquid switching valve 43 is a three-way solenoid valve, and switches the connection between the fluid supply pipe 41 and the gas supply pipe 35 at the time of non-energization and the connection between the fluid supply pipe 41 and the connection pipe 44 at the time of electricity.

  The connection pipe 44 is connected to a water supply pipe 45 as a humidification liquid supply pipe and a chemical liquid supply pipe 46, respectively. The water supply pipe 45 is connected to the water pipe W1 via a valve 47, a check valve and a pressure reducing valve. In the present embodiment, tap water from the water pipe W1 is used as the humidifying liquid.

  The chemical solution supply pipe 46 is connected to the chemical solution tank Tc1 via a valve 48 and a ball valve. The valves 47 and 48 function as a switching valve for supplying the water from the water pipe or the chemical solution from the chemical solution tank Tc1 to the connection tube 44 by opening one side and closing the other.

<Arrangement of Two Fluid Nozzles N1 to N5>
Next, the arrangement of the two-fluid nozzles N1 to N5 will be described with reference to FIG. In the present embodiment, it is assumed that the spaces in the rooms R1, R2 and R3 are disinfected. A drug solution tank Tc1 storing a drug solution used for sterilization of the space in the rooms R1 to R3 is installed at a place other than the rooms R1 to R3.

The rooms R1 and R2 communicate with the outside through the doors D1 and D2. The room R3 communicates with the rooms R1 and R2 through the doors D3 and D4, respectively.
Humidity sensors M1 and M2 are attached to the side surfaces of the columns of the rooms R1 and R2, respectively. The humidity sensors M1 and M2 detect the humidity of each of the rooms R1 and R2.

  Fire alarm A1 and A2 are attached to the ceiling of the approximate center of room R1 and R2, respectively. Each of the fire alarms A1 and A2 is a device that senses smoke from a fire, and detects occurrence of smoke by using diffuse reflection of light in the case of hitting a particle of smoke and outputs a warning.

  In the room R1, two fluid nozzles N1, N2 of the sterilization apparatus are disposed. Further, in the room R2, two fluid nozzles N3, N4, N5 of the sterilization apparatus are disposed. The two fluid nozzles N1 to N5 are suspended from the ceiling at a height at which the spray ports are lower than the fire alarms A1 and A2. Each of the two-fluid nozzles N1 to N5 sprays the liquid in the direction indicated by the arrow.

<Control of the bacteria removal device 30>
Control of the sterilization apparatus 30 is demonstrated using FIG. The sterilization apparatus 30 includes a control unit 50. The control unit 50 controls humidification and sterilization in the rooms R1 to R3.

  The control unit 50 is supplied with the humidity detected by the humidity sensors M1 and M2 and a signal from the human sensor 60 provided in the rooms R1 and R2. The control unit 50 supplies control signals to each of the air supply valves V1 to V5, the gas liquid switching valve 43, the valves 47 and 48, and the gas supply valve 36, and the control signals of these valves (V1 to V5, 43, 47, 48) Switch over. Furthermore, the control unit 50 controls the start and stop of the compressor C1.

  The operation unit 61 and the display unit 62 are connected to the control unit 50. The operation unit 61 and the display unit 62 are touch panels. The display unit 62 displays the manual start or stop of humidification or sterilization and the current humidity and the like. The operation unit 61 is used to stop the humidification and the sterilization, and to change the set humidity in the humidification.

The control unit 50 includes a humidification control unit 51, a sterilization control unit 52, and a sterilization condition storage unit 55.
The humidification control unit 51 sprays water to execute the humidification process. The humidification control unit 51 stores the set humidity. For example, 50% RH is used as the set humidity. The humidification control unit 51 performs the humidification of the rooms R1 to R3 by spraying water from the two-fluid nozzles N1 to N5 so that the humidity in the rooms R1 to R3 becomes the set humidity. Further, the humidification control unit 51 changes the set humidity in accordance with the operation from the operation unit 61.

  The sterilization control unit 52 executes the chemical solution spraying stage, the holding stage, and the purge stage. In the chemical solution spraying stage, the chemical solution is sprayed, in the holding stage, the spraying of the chemical solution is stopped and held, and in the purge stage, the chemical solution is discharged from the pipe.

  The sterilization control unit 52 stores the time for carrying out the holding step (holding time) and the time for carrying out the purging step (purge time). In this embodiment, 7 minutes is used as the holding time, and 15 minutes is used as the purge time. When the chemical solution is sprayed in the purge stage, the humidity in the rooms R1 and R2 increases. Also in this case, the holding time is determined as the time for lowering the relative humidity so that the humidity of the rooms R1 and R2 does not become the reference value or more. In the present embodiment, 85% RH is used as a reference value. When the relative humidity in the rooms R1 to R3 is lower than the reference value, the fire alarms A1 and A2 do not output an alarm.

  FIG. 4 is a graph showing the relationship between the time from the start of spraying and the relative humidity. In this graph, the chemical solution spray is 11 minutes, the holding time is 7 minutes, and the purge time is 15 minutes. As shown in this graph, the relative humidity rises by the chemical solution spraying, and the relative humidity decreases after exceeding the relative humidity (70% RH) where the inside of the rooms R1 to R3 can be disinfected. In the purge phase, the relative humidity rises again. Then, in the purge stage, the relative humidity rises and then falls again. Here, the peak value of the relative humidity of the purge stage is lowered by prolonging the holding time. In this embodiment, the peak value of the purge stage can be made lower than 85% RH with a holding time of 7 minutes.

The sterilization control unit 52 of the present embodiment performs chemical solution spraying using the sterilization conditions stored in the sterilization condition storage unit 55.
As shown in FIG. 5, the bacteria removal condition storage unit 55 stores bacteria removal conditions. The sterilization conditions differ depending on the humidity at the start of the sterilization and the rooms R1 and R2. In the present embodiment, when the humidity at the start of sterilization is 60% RH (relative humidity 60%) or less, as in spring, autumn and winter, the humidity control is performed, and the sterilization is started as in summer. When the humidity exceeds 60% RH, timer control is performed. In the case of humidity control, the chemical solution is sprayed until the target relative humidity for each of the rooms R1 and R2 is reached. If the humidity of the humidity sensors M1 and M2 reaches and exceeds the target relative humidity, even if the spraying is immediately stopped, the humidity of the rooms R1 to R3 rises, and the relative humidity after spraying becomes 70% or more It can be disinfected. In the case of timer control, the chemical solution is sprayed during a predetermined chemical solution spraying time. In this embodiment, the target relative humidity in humidity control of the rooms R1 and R2 is set to 68% RH and 77% RH, respectively, and the chemical solution spraying time in the timer control of the rooms R1 and R2 is set to 12 minutes and 14 minutes, respectively. .

  Next, processing using the sterilization apparatus according to the present embodiment will be described with reference to FIGS. 6 and 7. In the present embodiment, humidification control is performed on the rooms R1 to R3 to avoid dryness during the time when a person is in the daytime, and the sterilization control process is performed at the sterilization start time in the middle of the night. In this embodiment, by closing the doors D1 and D2 and opening the doors D3 and D4, not only the rooms R1 and R2 but also the room R3 are humidified and disinfected.

<Humidification control processing>
As shown in FIG. 6, in the daytime, the control unit 50 executes the humidification control process based on the humidity of the rooms R1, R2 (step S1). Specifically, the humidification control unit 51 of the control unit 50 acquires the humidity from the humidity sensors M1 and M2. The humidification control unit 51 performs humidification when the acquired humidity is lower than the set humidity.

  In this case, as shown in FIG. 7A, the humidification control unit 51 of the control unit 50 starts the compressor C1, connects it to the gas supply pipe 31 by switching the air supply valves V1 to V5, and compresses it. Air is supplied to each of the two-fluid nozzles N1 to N5.

In addition, the humidification control unit 51 performs the opening operation of the valve 47 and the closing operation of the valve 48, and supplies the water from the water pipe W1 to the gas liquid switching valve 43. Further, the humidification control unit 51 causes the fluid supply pipe 41 and the connection pipe 44 to communicate with each other by the switching operation of the gas / liquid switching valve 43.
As described above, compressed air and water are supplied to the two-fluid nozzles N1 to N5, water is sprayed to the rooms R1 to R3, and the humidity of the rooms R1 to R3 increases.

  When the humidity of the rooms R1 to R3 becomes the set humidity, the humidification control unit 51 of the control unit 50 stops the humidification. Specifically, the humidification control unit 51 opens the two fluid nozzles N1 to N5 side by switching operation of the gas liquid switching valve 43 and the air supply valves V1 to V5, and stops the compressor C1. As a result, the supply of tap water and compressed air to each of the two-fluid nozzles N1 to N5 is stopped, and the humidification is stopped.

<Elimination control processing>
After that, as shown in FIG. 6, when the bacteria removal start time has come (in the case of “YES” in step S2), the bacteria removal control unit 52 executes acquisition processing of humidity at start (step S3). Specifically, first, the sterilization control unit 52 determines whether there is a person in the rooms R1 to R3 based on the signal from the human sensor 60. If it is determined that there are no people in the rooms R1 to R3, the sterilization control unit 52 acquires the humidity of the humidity sensors M1 and M2.

  Next, the sterilization control unit 52 executes a process of determining whether the acquired start humidity is 60% RH or less (step S4). Here, when the humidity sensors M1 and M2 are 60% RH or less (in the case of “YES” in step S4), the humidity control processing is executed.

  Specifically, as shown in FIG. 7B, in the humidity control process, the sterilization control unit 52 starts the compressor C1, and switches the air supply valves V1 to V5 to operate the gas supply pipe 31 and the like. It connects and supplies compressed air to each two fluid nozzle N1-N5.

  In addition, the sterilization control unit 52 supplies compressed air to the chemical solution tank Tc1 by opening the gas supply valve 36, and applies pressure to the chemical solution. Then, the sterilization control unit 52 performs the closing operation of the valve 47 and the opening operation of the valve 48. Furthermore, the sterilization control unit 52 connects the fluid supply pipe 41 and the connection pipe 44 by switching the gas-liquid switching valve 43, and supplies the chemical solution from the chemical solution tank Tc1.

By the above, a chemical | medical solution and compressed air are supplied to each two fluid nozzle N1-N5, and a chemical | medical solution is sprayed by room R1 and R2 (step S5). And relative humidity of room R1-R3 rises by spraying of a medical fluid.
When the detected humidity from the humidity sensors M1 and M2 does not exceed the target relative humidity ("NO" in step S6), the bacteria removal control unit 52 continues to spray the chemical solution.

  On the other hand, when the acquired start-time humidity exceeds 60% RH (in the case of “NO” in step S 4), the sterilization control unit 52 executes timer control processing.

In this timer control process, the sterilization control unit 52 activates the compressor C1 and connects it to the gas supply pipe 31 by switching the air supply valves V1 to V5 as in the humidity control process. Furthermore, the sterilization control unit 52 performs the closing operation of the valve 47, the opening operation of the valve 48, and the switching operation of the gas liquid switching valve 43. Thereby, a chemical | medical solution and compressed air are supplied to each two fluid nozzle N1-N5, and a chemical | medical solution is sprayed by room R1-R3 (step S7).
Then, the sterilization control unit 52 continues spraying the chemical solution until the spraying time has elapsed from the start of spraying (in the case of “NO” in step S8).

  Thereafter, in the humidity control process, when the target relative humidity is exceeded, or when the spray time has elapsed in the timer control process (“YES” in steps S6 and S8), the sterilization control unit 52 performs the holding process. Execute (step S9).

Specifically, the sterilization control unit 52 stops the liquid supply to the gas liquid switching valve 43 by closing the valves 47 and 48. Furthermore, the sterilization control unit 52 stops the supply of compressed air to each of the two-fluid nozzles N1 to N5 by switching the air supply valves V1 to V5, and stops the compressor C1.
As described above, the supply of the liquid and the compressed air is stopped in each of the two fluid nozzles N1 to N5, and the spraying from each of the two fluid nozzles N1 to N5 is stopped. And the state which stopped this spraying is maintained until holding time passes.

When the holding time has elapsed, the sterilization control unit 52 executes a purge process (step S10).
Specifically, as shown in FIG. 7C, the sterilization control unit 52 activates the compressor C1, and switches the compressed air into the two-fluid nozzles N1 to N5 by switching the air supply valves V1 to V5. Supply to Furthermore, the sterilization control unit 52 causes the fluid supply pipe 41 and the gas supply pipe 35 to communicate with each other by the switching operation of the gas liquid switching valve 43. In this case, the valves 47 and 48 and the gas supply valve 36 are closed.
As described above, the compressed air is supplied to the fluid supply pipe 41, and the chemical solution remaining in the fluid supply pipe 41 is sprayed from the two-fluid nozzles N1 to N5.

When the purge time has elapsed after the start of the purge process, the sterilization control unit 52 opens the two-fluid nozzles N1 to N5 by switching the air supply valves V1 to V5, and stops the compressor C1. As a result, the compressed air is not supplied to the two fluid nozzles N1 to N5, and the spraying from the two fluid nozzles N1 to N5 ends.
Thus, the sterilization control process is completed, and the next humidification control process (step S1) is prepared.

According to the present embodiment, the following effects can be obtained.
(1) The two-fluid nozzles N1 to N5 of the sterilization apparatus 30 according to the present embodiment spray compressed water from the water supply pipe 45 using compressed air to humidify the rooms R1 to R3 and supply chemical solutions The chemical solution supplied from the pipe 46 is sprayed to sterilize the rooms R1 to R3. Thereby, humidification and sterilization can be performed using the same two fluid nozzles N1 to N5.

  (2) In the sterilization apparatus 30 of the present embodiment, the water supply pipe 45 and the chemical solution supply pipe 46 are connected to the fluid supply pipe 41 connected to the two-fluid nozzle N1 to N5 via the valves 47 and 48. Thus, water and a chemical solution can be supplied using the fluid supply pipe 41. In particular, when the installation location of the two-fluid nozzle N1 to N5 and the water pipe W1 or the chemical solution tank Tc1 are separated, the number of pipes can be reduced.

  (3) In the present embodiment, after the chemical solution is sprayed (steps S5 and S7), the purge process (step S10) is performed before the humidification control process (step S1). Thereby, the medical fluid remaining in the fluid supply pipe 41 can be discharged.

  (4) In the present embodiment, compressed air is supplied to the fluid supply pipe 41 connected to the two-fluid nozzles N1 to N5 in the purge process (step S10). Thereby, the medical fluid remaining in the fluid supply pipe 41 can be discharged quickly.

  (5) In the present embodiment, after the chemical solution is sprayed (steps S5 and S7), the holding process (step S9) is performed before the purge process (step S10). Thereby, in the purge process (step S10), an increase in humidity can be suppressed. For example, the alarm output of the fire alarm A1, A2 based on high humidity can be suppressed. Furthermore, the maximum humidity in the purge process (step S10) can be set to a humidity (70% RH) or more at which sterilization is performed.

Also, the present embodiment may be modified as follows.
In the above embodiment, the holding time in the holding process after chemical solution spraying is 7 minutes. The holding time is not limited to this, and may be changed depending on the size of the room to be sterilized, the amount of the chemical solution, and the like. Further, the purge process may be started based on the humidity detected in the holding process. Specifically, the sterilization control unit 52 of the control unit 50 stores a predetermined relative humidity (purge start humidity) at which the purge is started. Then, the sterilization control unit 52 starts the purge process when the detected humidity from the humidity sensors M1 and M2 falls below the purge start humidity in the holding process.

  In the embodiment, in the purge process (step S9), the compressed air is supplied to the fluid supply pipe 41 from the gas supply pipe 35, and the chemical solution remaining in the fluid supply pipe 41 is discharged. The fluid used to discharge the chemical solution remaining in the fluid supply pipe 41 is not limited to compressed air, and may be water.

  In the above embodiment, the control unit 50 sprays the liquid chemical after confirming that there are no people in the rooms R1 to R3 based on the signal from the human sensor 60. The confirmation that the person is not present before the spray of the chemical solution is not limited to the signal from the human sensor 60, and may be performed based on, for example, the opening and closing of the doors D1 and D2 and the turning off of the illumination of the rooms R1 to R3.

  In addition, when intrusion of a person is detected by the human sensor 60 or the door sensor during spraying of a chemical solution, chemical solution spraying may be stopped. Then, after stopping the chemical solution spraying, when the absence of a person is detected by the human sensor 60, the chemical solution spraying which has been stopped is restarted. In this case, the humidity of the humidity sensors M1 and M2 is acquired, and in the case of humidity control, spraying is performed until the target relative humidity is reached, and in the case of timer control, the remaining time of chemical solution spraying is resprayed.

  -In the said embodiment, the tap water was used as liquid for humidification. The liquid used for humidification is not limited to tap water. For example, a low concentration disinfecting solution which does not affect humans, or a liquid with a scent such as aroma water may be used.

  In the above embodiment, the control unit 50 executes the chemical solution spraying process, the holding process and the purge process when the bacteria removal start time comes. The start of the chemical solution spraying, the control of the chemical solution spraying (humidity control or timer control), the setting of the chemical solution spraying time, the holding time, and the purge time may be performed by human operation.

  A1, A2: fire alarm, C1: compressor, D1, D2, D3, D4: door, M1, M2: humidity sensor, N1, N2, N3, N4, N5: two-fluid nozzle, R1, R2, R3: room , W1 ... water pipe, Ta1 ... air tank, V1, V5: air supply valve, 30 ... sterilization apparatus, 31, 35 ... gas supply pipe, 36 ... gas supply valve, 41 ... fluid supply pipe, 43 ... gas liquid switching Valve 44 44 connection pipe 45 water supply pipe 46 chemical solution supply pipe 47, 48 valve 49 drain valve 50 control unit 51 humidification control unit 52 sterilization control unit 55 ... bacteria elimination condition storage unit, 60 ... human detection sensor, 61 ... operation unit, 62 ... display unit.

Claims (5)

A sterilization method for disinfecting the inside of a space using a two-fluid nozzle connected to a liquid supply pipe to which a chemical solution used for sterilization is supplied and spraying the chemical solution using a gas,
A humidifying step of supplying the humidifying liquid to the two-fluid nozzle from the humidifying liquid supply pipe connected to the liquid supply pipe via the switching valve, spraying the humidifying liquid, and humidifying the space When,
The medical solution is supplied to the two-fluid nozzle from a chemical liquid supply pipe connected to the liquid supply pipe via the switching valve, and a sterilizing step of sterilizing the space is performed. How to disinfect.   The method according to claim 1, further comprising performing a purge step of discharging the chemical solution in the liquid supply pipe to the space after spraying the chemical solution and before spraying the humidifying liquid. The sterilization stage is
A chemical solution spraying step of spraying a chemical solution from the two-fluid nozzle;
Stopping the spraying from the two-fluid nozzle such that the relative humidity of the space in the purging step becomes lower than a reference value;
The method according to claim 2, wherein the purge step is performed after the holding step. A sterilization apparatus comprising: a two-fluid nozzle connected to a liquid supply pipe to which a chemical solution used for sterilization is supplied and spraying the chemical solution using a gas;
A humidifying liquid supply pipe and a chemical liquid supply pipe connected to the liquid supply pipe via a switching valve;
A control unit that controls switching of the switching valve;
The control unit
A humidification control process of supplying the humidification liquid to the two-fluid nozzle from the humidification liquid supply pipe and spraying the humidification liquid to humidify the space is executed.
A bacteria removal apparatus characterized by performing a bacteria removal control process of supplying the drug solution to the two-fluid nozzle from the drug solution supply pipe and removing the space.   The sterilization control according to claim 4, wherein the control unit executes a purge process of discharging the chemical solution in the liquid supply pipe to the space after spraying the chemical solution and before spraying the humidifying liquid. apparatus.

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