Chlorine dioxide gas generator

Abstract

To provide technology that can prevent corrosion of equipment even when a high concentration of chlorine dioxide is generated and keeps the equipment clean.SOLUTION: A chlorine dioxide gas generator comprises a chlorine dioxide gas generating section that generates a high concentration of chlorine dioxide gas and a blower that sends out the chlorine dioxide gas generated in the chlorine dioxide gas generating section. The blower has a blade that rotates, a motor housing, a motor housed in the motor housing, and a shaft that transmits the power of the motor to the blade. A rotating seal that seals between the shaft and the motor housing contains grease for preventing the chlorine dioxide gas from entering the inside of the motor housing.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a chlorine dioxide gas generator and a method for controlling the chlorine dioxide gas generator.

Background Art

[0002] In spaces such as hospitals and factories that may be contaminated by pathogens such as bacteria and viruses, decontamination with chlorine dioxide gas is performed. However, high-concentration chlorine dioxide gas is highly corrosive, and there is a risk that the generated chlorine dioxide gas may corrode the chlorine dioxide gas generator itself. Regarding such problems, Patent Document 1 discloses a technique capable of suppressing the influence of corrosion by chlorine dioxide gas.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, with the technique of Patent Document 1 described above, it may be difficult to suppress corrosion inside components such as a blower for sending out the gas mounted in the chlorine dioxide gas generator.

[0005] As described above, in existing chlorine dioxide gas generators, depending on the concentration of generated chlorine dioxide, further improvements are required to prevent corrosion of the device itself. Furthermore, not only corrosion by the generated chlorine dioxide but also cleaning for keeping the flow path through which sodium chlorite solution or hydrochloric acid used for generating chlorine dioxide flows clean is indispensable, and it has been a problem to perform this cleaning reliably and efficiently. The purpose of the present application is to provide a technique capable of preventing corrosion of equipment even when generating high-concentration chlorine dioxide gas and keeping the equipment clean. [Means for solving the problem]

[0006] The present invention can be realized in the following forms.

[0007] (1) One embodiment of the present invention is provided by a chlorine dioxide gas generator comprising a chlorine dioxide gas generating unit that generates high-concentration chlorine dioxide gas and a blower that sends out the chlorine dioxide gas generated in the chlorine dioxide gas generating unit. The blower in this embodiment of the chlorine dioxide gas generator comprises a rotating blade, a motor housing, a motor housed in the motor housing, and a shaft that transmits the power of the motor to the blade, and a rotating seal that seals the space between the shaft and the motor housing is fitted with grease to prevent the chlorine dioxide gas from entering the inside of the motor housing. This type of chlorine dioxide gas generator prevents highly corrosive chlorine dioxide gas from entering the motor housing through the rotating seal and corroding the motor. Here, "high concentration" means a concentration at which chlorine dioxide gas can corrode equipment such as blowers, and for example, it can be 20 ppm or higher, or 100 ppm or higher in equipment using highly corrosion-resistant materials.

[0008] (2) In the chlorine dioxide gas generator of the above form, the rotating seal may be a labyrinth seal. By using a labyrinth seal and applying grease to the sealing part, it becomes easier to prevent chlorine dioxide gas from entering the inside of the motor housing.

[0009] (3) In the chlorine dioxide gas generator of the above configuration, the chlorine dioxide gas generating unit is: The system may include a sodium chlorite water storage tank for storing sodium chlorite water and a hydrochloric acid storage tank for storing hydrochloric acid, and may generate chlorine dioxide gas by a chemical reaction between the sodium chlorite water and the hydrochloric acid. Furthermore, it may include a cleaning solution storage tank for storing cleaning solutions for cleaning the sodium chlorite water and hydrochloric acid flows, and may have a first switching valve for switching between the sodium chlorite water and the cleaning solution, and a second switching valve for switching between the hydrochloric acid and the cleaning solution. This type of chlorine dioxide gas generator not only prevents corrosion caused by the generated chlorine dioxide gas, but also allows for efficient cleaning of the chemical solution flow path by switching the aforementioned switching valve, thereby enabling the chlorine dioxide gas generator to be kept in a clean, corrosion-free state.

[0010] (4) One embodiment of the present invention is provided as a control method for a chlorine dioxide gas generator that decontaminates a space to be decontaminated with chlorine dioxide gas, using a chlorine dioxide gas generator equipped with a sealing structure that prevents corrosion of equipment by chlorine dioxide gas through a rotating seal mechanism. The control method for a chlorine dioxide gas generator in this embodiment comprises: a gas generation step of generating a high concentration of chlorine dioxide gas by a chemical reaction between sodium chlorite solution and hydrochloric acid; an exposure step of introducing the generated chlorine dioxide gas into a space to be decontaminated and exposing it for a predetermined time; a recovery step of recovering the chlorine dioxide gas introduced into the space to be decontaminated after the exposure step; a cleaning solution switching step of switching the sodium chlorite solution and the hydrochloric acid, respectively, to cleaning solutions after the recovery step or in parallel with the recovery step; and a cleaning step of cleaning the flow paths of the sodium chlorite solution and the hydrochloric acid using the cleaning solutions. Using this control method for a chlorine dioxide gas generator, it is possible not only to prevent corrosion of the equipment contained in the chlorine dioxide gas generator, but also to keep the entire device in a clean, corrosion-free state by switching to sodium chlorite solution or hydrochloric acid as the cleaning solution and cleaning the flow paths of each liquid. [Brief explanation of the drawing]

[0011] [Figure 1] A diagram illustrating the entire system of a chlorine dioxide gas generator. [Figure 2] External view of a blower (turbo fan) used in a chlorine dioxide gas generator. [Figure 3] An exploded view of the blower (turbo fan) used in a chlorine dioxide gas generator. [Figure 4] An explanatory diagram showing the entire system of a chlorine dioxide gas generator, including the cleaning function. [Figure 5] An explanatory diagram showing a decontamination process using a chlorine dioxide gas generator. [Figure 6] A perspective view of the chlorine dioxide gas generator from the front (with the outer panel removed). [Figure 7] Perspective view of the rear exterior of the chlorine dioxide gas generator (with the outer panel removed). [Figure 8] A six-view drawing of the chlorine dioxide gas generator (with the protective panel removed). [Modes for carrying out the invention]

[0012] Hereinafter, preferred embodiments and examples of the present invention will be described with reference to the drawings.

[0013] 1. Embodiments: Figure 1 is an explanatory diagram showing the entire system of the chlorine dioxide gas generator 10. The chlorine dioxide gas generation unit 100 mixes sodium chlorite solution 51 and hydrochloric acid 53 and generates chlorine dioxide gas via the aeration tank 60. The generated high-concentration chlorine dioxide gas is blown out of the chlorine dioxide gas generator 10 by the blower 20.

[0014] Figure 2 is an external view of the blower 20 used in the chlorine dioxide gas generator 10. Further, FIG. 3 shows an exploded view of the blower 20. The blower 20 is composed of a rotating blade 24, a motor housing 21, a motor 27 housed in the motor housing 21, and a shaft 26 that transmits the power of the motor 27 to the blade 24. The chlorine dioxide gas generated in the chlorine dioxide gas generation unit 100 is sucked in from the intake port 22 and exhausted from the exhaust port 23, and thus is sent out to the outside of the device.

[0015] The high-concentration chlorine dioxide gas sucked in from the intake port 22 is highly corrosive. If it enters the inside of the motor housing 21 through the rotary seal 25 that constitutes the bearing part, it will corrode the motor 27. To prevent this, grease is used for the rotary seal 25.

[0016] The rotary seal 25 is preferably a labyrinth seal. By adopting a labyrinth seal and filling grease in the gap between the rotor and the stator of the labyrinth seal, it is possible to effectively prevent the chlorine dioxide gas from entering the inside of the motor housing 21.

[0017] After generating the chlorine dioxide gas, in order to keep the device clean, it is desirable to wash the chemical liquid flow path. In the embodiment shown in FIG. 4, the chlorine dioxide gas generation unit 100 is configured to store sodium chlorite water in the chemical liquid storage tank 51 and store hydrochloric acid in the chemical liquid storage tank 53. In addition to the chemical liquid storage tanks 51 and 53, cleaning liquid storage tanks 52 and 54 for storing cleaning liquid are provided.

[0018] The cleaning of the chemical liquid flow path can be performed by operating the switching valves 71 and 72 so as to switch the sodium chlorite water to the cleaning liquid and at the same time switch the hydrochloric acid to the cleaning liquid.

[0019] By using the chlorine dioxide gas generator 10 according to the present invention, it becomes possible to decontaminate the space to be decontaminated 90 with chlorine dioxide gas. Figure 5 is an explanatory diagram of the control method of the chlorine dioxide gas generator 10 for decontaminating the space to be decontaminated 90 using the chlorine dioxide gas generator 10.

[0020] The decontamination process using chlorine dioxide is set by the initial setting P1. Here, the concentration of chlorine dioxide gas and the exposure time are set as needed. In the gas generation process P2, a high concentration of chlorine dioxide gas is generated by a chemical reaction between sodium chlorite solution and hydrochloric acid and introduced into the space to be decontaminated 90, thereby increasing the chlorine dioxide gas concentration in the space to be decontaminated 90 to a predetermined value. In the exposure process P3, decontamination is performed by exposing the space to be decontaminated 90 to a predetermined amount of high concentration of chlorine dioxide gas for a predetermined time. The recovery process P4 is the process of recovering the chlorine dioxide gas that has filled the space to be decontaminated 90. In the cleaning solution switching process P5, the first switching valve 71 is driven to switch from sodium chlorite solution to the cleaning solution, and at the same time, the second switching valve 72 is driven to switch from hydrochloric acid to the cleaning solution. In the cleaning process P6, the cleaning solution is flowed through the chemical solution channel instead of the chemical solution to clean the channel.

[0021] The cleaning solution switching process P5 and the cleaning process P6 may be performed after the recovery process P4, or they may be performed in parallel with the recovery process P4. The recovery process P4 continues until the chlorine dioxide concentration in the decontaminated space 90 falls below a predetermined value. During this time, the cleaning solution switching process P5 and the cleaning process P6 can be carried out, making it possible to complete the series of decontamination processes using chlorine dioxide gas efficiently and in a short amount of time.

[0022] 2. Examples: The following describes in detail specific embodiments implemented by the inventor of the present invention.

[0023] Figure 6 is a perspective view of the chlorine dioxide gas generator 10 according to the present invention, with the exterior panel removed to reveal the components, and Figure 7 is a perspective view of the rear of the same exterior. Figure 8 shows six views. The chlorine dioxide gas generating unit 100 consists of a reactor 30, pumps 41 and 42, chemical storage tanks 51 and 53, cleaning solution storage tanks 52 and 54, aeration tank 60, air pump 61, and switching valves 71 and 72 (not shown in Figures 6 and 7).

[0024] As can be seen in Figures 6, 7, and 8, the chlorine dioxide gas generator 100, blower 20, waste liquid solenoid valve 81, waste liquid storage tank 82, and controller CL that controls all of these are installed in a single enclosure. By installing the storage tanks 51, 52, 53, 54, and 82 for chemical solution, cleaning solution, and waste liquid, respectively, at the bottom of the enclosure, the ease of refilling and disposing of each liquid is improved, and stable operation is achieved by lowering the center of gravity during use. The controller CL is installed at the top of the enclosure to improve user operability and visibility.

[0025] The blower 20 that sends the chlorine dioxide gas generated in the chlorine dioxide gas generation unit 100 to the decontamination space 90 uses a turbo fan. Because turbo fans have high static pressure and can produce a large airflow, they can efficiently introduce chlorine dioxide gas into the decontamination space 90. However, depending on the configuration of the equipment and the decontamination space, it is also possible to use a sirocco fan or a propeller fan.

[0026] A labyrinth seal is used for the rotating seal 25 that constitutes the bearing section supporting the shaft 26 of the turbo fan 20. The grease that fills the gap between the rotor and stator of the labyrinth seal can be any grease that prevents the intrusion of chlorine dioxide gas, for example, a silicone-based grease can be used. Many labyrinth seals have a return hole to allow liquids that have entered the seal to return to their original position. However, the grease-filled portion of the present invention does not have this return hole, preventing the filled grease from flowing out of the seal and ensuring long-term blocking of chlorine dioxide gas.

[0027] The switching valves 71 and 72, which switch between the chemical storage tanks 51 and 53 and the cleaning solution storage tanks 52 and 54, use three-way solenoid valves. The use of solenoid valves enables automatic control by the controller CL. For the same reason, the waste liquid switching valve 81 also uses a solenoid valve.

[0028] Controller CL is configured as a device including a power supply, circuit breaker, relay, sequencer, control board, chlorine dioxide gas concentration meter, communication device, wireless communication antenna, and display panel. A gas concentration measuring device such as the one specified in Japanese Patent No. 6886208 can be used as the chlorine dioxide gas concentration meter. With this configuration, it is possible to automate all of the processes P2 to P6 in Figure 5, and furthermore, by communicating with a mobile terminal, it is possible to monitor the processing status and operate the device from outside the decontaminated space 90.

[0029] The equipment housed within the chlorine dioxide gas generator 10 generates heat, which needs to be expelled to the outside of the casing. However, when the device is in operation, the decontaminated space 90 is filled with a high concentration of chlorine dioxide gas, so simply ventilating it would result in corrosion of the equipment inside the casing. Therefore, intake holes are provided at predetermined locations on the casing of the chlorine dioxide gas generator 10, and activated carbon filters are installed in these intake holes to prevent chlorine dioxide gas from entering the casing. Exhaust holes are also provided at other predetermined locations, and exhaust fans are installed. This makes it possible to efficiently expel the heat generated inside the chlorine dioxide gas generator 10 while avoiding corrosion of the equipment.

[0030] By controlling the chlorine dioxide gas generator 10 described above, decontamination of the space to be decontaminated 90 with chlorine dioxide becomes possible. The space to be decontaminated 90 may include not only spaces that are likely to be contaminated with pathogens such as bacteria and viruses, such as factories, hospitals, schools, commercial facilities, and houses, but also narrow spaces used for specific purposes, such as biosafety cabinets, where bacteria and viruses are handled.

[0031] To decontaminate the space to be decontaminated 90, first, the space must be free of people, and the chlorine dioxide gas generator 10 is installed. Next, the controller CL of the chlorine dioxide gas generator 10 is operated to set the initial settings for the chlorine dioxide gas concentration and exposure time, and to establish communication with the mobile terminal. The exposure time can be set as appropriate depending on the type of bacteria or virus to be decontaminated. All subsequent operations are performed automatically, so the operator does not need to enter the space to be decontaminated 90. The chlorine dioxide gas generator 10 drives the respective pumps 41 and 42 to transfer sodium chlorite solution and hydrochloric acid to the reactor 30. The chlorine dioxide produced by the chemical reaction becomes a high-concentration chlorine dioxide gas in the aeration tank 60, is drawn into the intake port 22 of the corrosion-preventively treated turbo fan 20, and introduced into the space to be decontaminated 90 from the exhaust port 23.

[0032] The chlorine dioxide gas concentration meter built into the controller CL measures the chlorine dioxide gas concentration in the decontamination space 90 in real time. When a predetermined concentration is reached, decontamination is performed by exposure for a predetermined time. After decontamination, the chlorine dioxide gas remaining in the decontamination space 90 is recovered. This recovery can be done using an activated carbon filter or the like. When the chlorine dioxide gas concentration in the decontamination space 90 falls below 0.05 ppm, it becomes possible for people to enter, and the decontamination process is completed.

[0033] After the recovery process described above, or in parallel with the recovery process, the chemical flow path of the chlorine dioxide gas generator 10 can be cleaned. Here, by driving the three-way solenoid valves 71 and 72, pumps 41 and 42 guide the cleaning solution (in this case, cleaning water) into the flow path. At the same time, by operating the waste liquid switching valve 81, the cleaning solution after cleaning, along with the waste liquid, is stored in the waste liquid storage tank 82.

[0034] By following the above steps, the decontamination of the area to be decontaminated 90 is completed. The entire process can be performed automatically based on the information set in the controller CL.

[0035] 3. Summary: As described above, according to the present invention, it is possible to prevent chlorine dioxide gas from entering the motor housing of the blower used in the chlorine dioxide gas generator, thereby preventing corrosion of the motor. Furthermore, since the cleaning process of the device can be automated, the decontamination process by exposure to chlorine dioxide gas can be carried out efficiently and quickly while keeping the device clean. [Explanation of Symbols]

[0036] 10. Chlorine dioxide gas generator 100...Chlorine dioxide gas generating unit 20... Blower 21…Motor housing 22... Intake port 23... Exhaust port 24...feathers 25…Rotating seal 26...axis 27…motor 30… Reactor 41, 42… pumps 51, 53... Chemical solution storage tanks 52, 54… Cleaning fluid storage tanks 60... Aeration tank 61... Air pump 71, 72… Switching valve 81...Waste liquid switching valve 82...Waste liquid storage tank 90…Decontaminated space CL... Controller

Claims

1. A chlorine dioxide gas generating unit that generates high-concentration chlorine dioxide gas, The system includes a blower that delivers the chlorine dioxide gas generated in the chlorine dioxide gas generating unit, The blower comprises a rotating blade, a motor housing, a motor housed in the motor housing, and a shaft that transmits the power of the motor to the blade. The rotary seal that seals the space between the shaft and the motor housing is fitted with grease to prevent the chlorine dioxide gas from entering the inside of the motor housing. Chlorine dioxide gas generator.

2. The aforementioned rotating seal is a labyrinth seal. A chlorine dioxide gas generator according to claim 1.

3. The chlorine dioxide gas generating unit is A sodium chlorite water storage tank for storing sodium chlorite water, It includes a hydrochloric acid storage tank for storing hydrochloric acid, The chlorine dioxide gas is generated by the chemical reaction between the sodium chlorite solution and the hydrochloric acid, The system includes a cleaning solution storage tank for storing cleaning solutions for cleaning the sodium chlorite solution and the hydrochloric acid channels, respectively. A first switching valve for switching between the sodium chlorite solution and the cleaning solution, and a second switching valve for switching between the hydrochloric acid and the cleaning solution, A chlorine dioxide gas generator according to claim 1 or 2, having the following features.

4. A control method for a chlorine dioxide gas generator that uses a chlorine dioxide gas generator equipped with a sealing structure that prevents corrosion of equipment by chlorine dioxide gas through a rotating seal mechanism, for decontaminating a space to be decontaminated with the chlorine dioxide gas, A gas generation step in which a high concentration of chlorine dioxide gas is generated by a chemical reaction between sodium chlorite solution and hydrochloric acid, An exposure step involves introducing the generated chlorine dioxide gas into the space to be decontaminated and exposing it for a predetermined time, A recovery step is performed to recover the chlorine dioxide gas introduced into the decontaminated space after the exposure step, After the recovery step, or in parallel with the recovery step, a cleaning solution switching step is performed in which the sodium chlorite solution and the hydrochloric acid are switched to cleaning solutions, A cleaning step of cleaning the sodium chlorite solution and the hydrochloric acid channels using the cleaning solution, A control method for a chlorine dioxide gas generator having the following features.

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