Method and apparatus for spraying ozone-containing air and water

Abstract

To provide a spraying method and a spraying apparatus that simultaneously spray ozone and water and that can reduce wetting of an object to be sprayed without impairing a sterilizing (disinfecting) effect of ozone.SOLUTION: A method for spraying ozone-containing air and water sets a Sauter mean diameter of sprayed water to 4.7 to 9.3 μm by adjusting a pressure of air supplied to a two-fluid nozzle 11. The pressure of the air supplied to the two-fluid nozzle is adjusted based on a distance measured between the two-fluid nozzle and an object to be sprayed. An amount of ozone contained in the air is adjusted based on an amount of the air supplied to the two-fluid nozzle at the adjusted air pressure.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a sterilization and deodorization treatment using ozone gas. [Background technology]

[0002] The coronavirus, which emerged in Japan in January 2020 after passengers on a cruise ship developed symptoms, led to the practice of disinfecting palms with a simple lever-type disinfectant spray before entering commercial and public facilities. Many restaurants and other establishments also began using handheld trigger-type disinfectant sprays to disinfect tables, serving trays, and other surfaces.

[0003] Ethyl alcohol has long been used as such a disinfectant, but in recent years, ozone water has also been used as a disinfectant (Non-Patent Document 1).

[0004] These disinfectant sprays leave the palms or the table wet after disinfection, leaving the palms feeling uncomfortable or making it impossible to immediately use the table, etc. Furthermore, if the disinfectant is wiped off with a cloth, the effectiveness of the disinfectant may be diluted by the cloth.

[0005] Regarding the problem of wetting after spraying, a technology has been proposed in which, when spraying fragrances and deodorizers with a lever-type or trigger-type sprayer, particles with a particle diameter of 100 μm or more make up 50% or less of the volume distribution of the sprayed mist particles, preventing the toilet seat or floor from getting wet due to falling mist particles (Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-235949 [Non-Patent Document 1] SIC Co., Ltd., SIC Ozone Generating Spray (Internet, URL: https: / / sic-sic-sic.co.jp / product / ozonewater / ozntrdr / ) Summary of the Invention [Problem to be solved by the invention]

[0007] The technology proposed in Patent Document 1 is intended to spray an aroma / deodorizer into the toilet space or inside the toilet bowl. When spraying an aroma / deodorizer, the spray is not aimed at the toilet seat or floor, but at the space that includes these. Furthermore, the technology proposed in Patent Document 1 achieves its aroma / deodorizing effect by causing the aroma / deodorizer to volatilize and diffuse throughout the space, and does not seek to achieve an aroma / deodorizing effect in a small, localized area (such as the toilet seat or floor).

[0008] On the other hand, when disinfecting palms or tables, the disinfectant is sprayed onto a specific target, and the expected disinfecting effect is extremely localized. Due to the presence or absence of such a specific target and differences in the action of the spray to achieve its purpose, the technology proposed in Patent Document 1 cannot be directly applied to spraying disinfectant onto palms or tables.

[0009] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a spraying method and a spraying device that simultaneously sprays ozone and water, thereby reducing wetting of the object to be sprayed without impairing the sterilization (disinfection) effect of ozone. [Means for solving the problem]

[0010] The method for spraying ozone-containing air and water according to the present invention comprises the steps of: supplying air to a two-fluid nozzle; The pressure is adjusted to set the Sauter mean particle size of the sprayed water to 4.7 to 9.3 μm.

[0011] The pressure of the air supplied to the two-fluid nozzle is adjusted based on the distance measured between the two-fluid nozzle and the object to be sprayed. The amount of ozone contained in the air is adjusted based on the amount of air supplied to the two-fluid nozzle at the adjusted air pressure.

[0012] The spray device of the present invention comprises a two-fluid nozzle, an air pump that supplies pressurized air to the two-fluid nozzle, a water container that supplies water to the two-fluid nozzle, an ozone generator that generates ozone from the pressurized air before it is supplied to the two-fluid nozzle, a distance measuring device that measures the distance between the two-fluid nozzle and the object to be sprayed, and a control device with calculation functions.

[0013] The control device is configured to calculate the appropriate pressure of the pressurized air based on the distance measured by the distance measuring device and to control the operation of the air pump so that the pressurized air reaches the appropriate pressure. At this time, the Sauter mean particle size of the water sprayed from the two-fluid nozzle is 4.7 to 9.3 μm.

[0014] The control device is configured to calculate the amount of air discharged from the air pump from the appropriate pressure and to control the operation of the ozone generator so that the ozone concentration in the air discharged from the two-fluid nozzle becomes a specific concentration. [Effects of the Invention]

[0015] According to the present invention, it is possible to provide a spraying method and a spraying device that simultaneously sprays ozone and water, which reduces wetting of the object to be sprayed without impairing the sterilization (disinfection) effect of ozone. [Brief explanation of the drawings]

[0016] [Figure 1] Figure 1 shows the testing equipment for the sterilization effect of water spray with ozone gas. [Figure 2] Figure 2 shows the test equipment for the deodorizing effect of ozone gas sprayed onto water. [Figure 3] Figure 3 is a schematic diagram of a two-fluid nozzle sprayer, which is the prototype of the sprayer. [Figure 4] FIG. 4 is a four-view diagram of the spray device. [Figure 5]FIG. 5 is a system block diagram of the spraying operation of the spray device. [Figure 6] FIG. 6 is a flowchart of the sterilization process using the spray device. [Figure 7] FIG. 7 is a diagram showing the relationship between the air pressure, the air flow rate, and the reach in a two-fluid nozzle. DETAILED DESCRIPTION OF THE INVENTION

[0017] Figure 1 shows a test device 1 for testing the sterilization effect of water spraying with ozone gas. Figure 1(a) shows the overall configuration of the test device 1, and (b) shows a top view of the chamber 2 in the test device 1.

[0018] The test apparatus 1 consists of a chamber 2, an ozone gas supply device 3, and a water supply device 4. The chamber 2 is a cubic acrylic box that is 150 mm long, 150 mm wide, and 150 mm high in plan view. A two-fluid nozzle 11 is attached to the top surface of the chamber 2 so that it can spray into the chamber 2.

[0019] The ozone gas supply device 3 is composed of a two-fluid nozzle 11, an air compressor 12, a pressure accumulator 13, an air filter 14, a pressure reducing valve 15, a flow rate adjusting valve 16, a flow meter 17, and an ozone generator 18. The flow rate adjusting valve 16 adjusts the amount of air supplied to the two-fluid nozzle 11. The ozone generator 18 uses a silent discharge type, and generates 50 mg / h of ozone. The water supply device 4 is composed of a 1 L transparent resin container 21 with a lid and a resin tube 22. One end of the resin tube 22 penetrates the lid of the transparent resin container 21 and opens into the interior of the transparent resin container 21 , and the other end is connected to the liquid supply port of the two-fluid nozzle 11 .

[0020] Table 1 shows the results of a preliminary investigation into the size of droplets sprayed into a mist when air is supplied to the two-fluid nozzle by the ozone gas supply device 3, in relation to the spray conditions. The two-fluid nozzle 11 used was model MF008 manufactured by Nozzle Network Co., Ltd. The investigation into the relationship between the spray conditions and droplet size was carried out using the test apparatus 1 shown in Figure 1, in which the two-fluid nozzle 11 was removed from the chamber 2 and fixed so as to spray horizontally.

[0021] The air pressure is the value of the pressure gauge on the primary side of the ozone generator 18, and the air flow rate is the value of the flow meter 17. The water flow rate was calculated from the difference in weight of the transparent resin container 21 containing water before and after spraying and the spraying time.

[0022] The mean particle size of the sprayed droplets is the Sauter mean diameter (SMD) value measured using the AEROTRAC II laser diffraction particle size distribution analyzer sold by Microtrac-Bell (URL: https: / / www.microtrac.com / jp / products / particle-size-shape-analysis / laser-diffraction / aerotrac-ii / ).

[0023] The "reaching distance" was determined by spraying from the two-fluid nozzle 11 horizontally in a windless state, slowly approaching a glass plate fixed vertically to a stand from a distance from the two-fluid nozzle 11 until water droplets were confirmed to adhere to the glass.

[0024] [Table 1]

[0025] The reach distances in Table 1 are the distances that the spray droplets reach under each condition and the distance beyond which they cannot reach. Under each condition, the greater the distance between the two-fluid nozzle 11 and the object to be sprayed, the smaller the amount of spray droplets that reach per unit area of ​​the object to be sprayed, and the less wetting there is. In an environment with a temperature of 20°C and humidity of 50%, the "boundary between wetting and not wetting" for droplets sprayed by the two-fluid nozzle 11 is half the reach distance.

[0026] Next, the effects of each spraying condition on sterilization efficacy were examined. To examine sterilization efficacy, Escherichia coli (NBRC3301 derived from the K12 strain) provided by the National Institute of Technology and Evaluation (NITE) was used. The sample used in the study was prepared by diluting a dry ampule approximately 1,000 times with purified water that had been boiled and then returned to room temperature. 0.1 ml of the diluted solution was then dropped onto a 2 cm square piece of white cotton cloth Cw placed in a petri dish, the dish was then covered, and the dish was stored in a constant temperature bath at 35°C for 5 hours.

[0027] The petri dishes, white cotton cloth and glassware were sterilized in an autoclave, and all of the above-mentioned procedures were carried out in a clean bench.

[0028] The effects on sterilization of ozone-containing air and mist water (hereinafter referred to as "ozone fog") sprayed from a two-fluid nozzle 11 were investigated using a test apparatus 1 shown in Figure 1 as follows. That is, the lid of the sample Ts (a petri dish containing a white cotton cloth containing E. coli) prepared as described above was removed and the sample was placed in a closed space, chamber 2, and ozone fog was sprayed downward from the two-fluid nozzle 11 from a position 15 cm above the sample Ts.

[0029] Ozone fog was sprayed for 30 seconds at each of the various air supply volumes shown in Table 1. The air supply volume was changed using pressure reducing valve 15 and flow rate adjusting valve 16, but the amount of ozone gas supplied to chamber 2 per unit time was determined by ozone generator 18 and was constant (50 mg / h).

[0030] After being exposed to the ozone fog spray environment for 30 seconds, the white cotton cloth (sample Ts) was washed with 20 ml of purified water placed in a petri dish and then transferred to a 200 ml beaker along with the purified water, which was then stirred with a magnetic stirrer. 0.1 ml of the resulting liquid was dropped onto an agar medium and cultured in an incubator for 6 hours. After culturing in this manner, the number of colonies on the agar medium was counted, and the effectiveness of the ozone fog spray conditions and spray state on sterilization of E. coli was compared.

[0031] Table 2 shows the ozone fog spray conditions and the sterilization effect of each test device 1 on E. coli.

[0032] [Table 2]

[0033] The sterilization effect in Table 2 was evaluated as "Good" if the number of colonies was reduced by 40% or more compared to the number of colonies in the control (305 x 0.4 = 122 or less), and as "Poor" if a decrease in the number of colonies was observed compared to the control.

[0034] From Table 2, it can be seen that when the spray conditions are d, e, and f, that is, when the air pressure is 200 to 400 kPa, the air flow rate is 3.2 to 5.5 Nl / min, and the water flow rate is 5 to 5.1 ml / min, the sterilization effect is excellent.

[0035] Next, we examined the deodorizing effect of ozone fog. Figure 2 shows the test device 1B for the deodorizing effect of ozone fog. Figure 2(a) shows the overall configuration of the test device 1B, and (b) shows a top view of the chamber 2B in the test device 1B.

[0036] Test apparatus 1B consists of chamber 2B, ozone gas supply device 3, and water supply device 4. Chamber 2B is a rectangular acrylic box that is 400 mm long, 300 mm wide, and 220 mm high in plan view. A two-fluid nozzle 11 is attached to the side of chamber 2B so that it can spray water horizontally into chamber 2B. Ozone gas supply device 3 and water supply device 4 are the same as those in test apparatus 1.

[0037] The odor to be deodorized was ammonia odor, and an aqueous ammonia solution was used as the odor source, which was prepared by diluting Japanese Pharmacopoeia ammonia water (concentration 9.5-10.5%) manufactured by Kenei Pharmaceutical Co., Ltd. with purified water 110 times. The aqueous ammonia solution was placed in a 300 ml beaker and placed in the spray direction of the two-fluid nozzle 11.

[0038] The circulation fan inside chamber 2B was operated and the beaker containing the ammonia solution was left inside chamber 2B for two hours, filling the chamber with the odor. After that, the beaker containing the ammonia solution was covered and ozone fog was sprayed into chamber 2B from the two-fluid nozzle 11 for one minute. After the spraying was completed, the gas inside chamber 2B was sampled with a syringe and transferred to a sampling bag. Three evaluators, A, B, and C, smelled the sampling bag and evaluated the degree of ammonia odor.

[0039] Table 3 shows the spray conditions of the ozone fog in Table 1, the results of the odor sensory test by three evaluators, and the deodorizing effect.

[0040] [Table 3]

[0041] Generally, odor intensity is used in sensory evaluations of deodorizing properties. The human sense of smell is said to be able to distinguish odors into six levels: no odor (odor intensity 0), perceive an odor (odor intensity 1, the level at which 50% of subjects perceive an odor), know what the odor is (odor intensity 2), easily detectable (odor intensity 3), strong odor (odor intensity 4), and very strong odor (odor intensity 5). This six-level classification is known as the "Six-Level Odor Intensity Labeling Method" and is commonly used (Odor Index Regulation Guidelines, March 2001, Environmental Management Bureau, Ministry of the Environment, URL: https: / / www.env.go.jp / air / akushu / guide_ind / full.pdf).

[0042] The odor evaluation values ​​in Table 3 were based on the following scale: 0: no odor, 1: barely detectable, 2: detectable odor, 3: easily distinguishable from ammonia odor, 4: strong ammonia odor, 5: intense ammonia odor. The odor evaluation in Table 3 was calculated by averaging the odor evaluation values ​​from the three evaluators. If the odor evaluation was two or more levels higher than the odor before spraying with ozone fog (average odor evaluation of 3 or less), it was marked as "Good," and if the average was above 3 but below 4, it was marked as "Poor."

[0043] Table 3 shows that the deodorizing effect is greatest when the spray conditions are d, e, and f, i.e., air pressure 200-400 kPa, air flow rate 3.2-5.5 Nl / min, and water flow rate 5-5.1 ml / min. Spray conditions d, e, and f refer to the cases where the average particle size of the sprayed droplets is 4.7-9.3 μm, as shown in Table 1.

[0044] Based on the above findings, a handheld spraying device 5 for spraying ozone fog (hereinafter abbreviated as "spraying device 5") will be described.

[0045] Figure 3 is a schematic diagram of a two-fluid nozzle spraying device 8, which is the prototype of spraying device 5, Figure 4 is a four-sided view of spraying device 5, and Figure 5 is a system block diagram of the spraying operation of spraying device 5. Spraying device 5 is a two-fluid nozzle spraying device 8 to which a distance measuring device 30 and a control device 7, which will be described later, have been added.

[0046] 3, 4, and 5, spray device 5 includes exterior casing 25, bi-fluid nozzle 11, air pump 26, ozone generator 27, resin tube 28, filter 29, distance measuring device 30, power supply 31, water container 32, and control device 7. Exterior casing 25 resembles a handgun and is a housing that houses bi-fluid nozzle 11, air pump 26, ozone generator 27, power supply 31, etc. Bi-fluid nozzle 11 is disposed in the portion of handgun-like exterior 25 that corresponds to the muzzle, with the spray nozzle facing outward. Bi-fluid nozzle 11 is the same as that used in test devices 1 and 1B.

[0047] Air pump 26 supplies pressurized air for spraying water to bi-fluid nozzle 11. A diaphragm type air pump is used as air pump 26. Ozone generator 27 is disposed between air pump 26 and bi-fluid nozzle 11, and generates ozone from the air discharged from air pump 26. A small silent discharge type ozone generator is used as ozone generator 27.

[0048] Resin tube 28 is used to supply water from water container 32 to bi-fluid nozzle 11. Filter 29 is attached to the tip of resin tube 28 and prevents dust from getting into the water supplied from water container 32 to bi-fluid nozzle 11.

[0049] The spray device 5 has a spray button 33 that is pressed when spraying, and a spray switch 34 that operates the air pump 26 and the ozone generator 27 when the spray button 33 is pressed. An electronic board 35 is housed inside the exterior casing 25.

[0050] Distance measuring device 30 measures the distance between spray device 5 and the object to be sprayed. Distance measuring device 30 is a laser distance sensor (laser distance measuring sensor module) manufactured by STMicroelectronics that serves as a distance measurement means and is protected by a plastic cover. Distance measuring device 30 is fixed to the top of exterior 25 (top in Figure 4(a)) with the laser irradiation direction aligned with the spray direction of two-fluid nozzle 11. A red light 39 and a green light 40 are provided on the surface of the cover on the opposite side of distance measuring device 30 from the laser irradiation direction. A red light 39 is used for red light 39, and a green light 40 is used for green light 40.

[0051] The power supply 31 operates the air pump 26, the ozone generator 27, the distance measuring device 30, and the control device 7. It is a rechargeable battery that operates the device and lights up the red light 39 and the green light 40.

[0052] The control device 7 controls the overall operation of the spray device 5. The control device 7 determines whether the distance between the spray device 5 and the object to be sprayed is within a range suitable for spraying, and if it is within the range, it optimizes the operation of the air pump 26 and the ozone generator 27 according to the distance.

[0053] 5, the control device 7 is made up of a calculation unit 41, a memory unit 42, and a display unit 43. The calculation unit 41 is a microcomputer provided on the electronic board 35 inside the exterior casing 25. The memory unit 42 is a semiconductor memory provided on the electronic board 35. The display unit 43 is a red light 39 and a green light 40. The control device 7 acquires distance information from the distance measuring device 30 via the input / output interface, and controls the operations of the air pump 26 and the ozone generator 27 based on this information.

[0054] Next, we will explain the operation of the control device 7 when sterilization, etc. is performed by spraying ozone fog with the spray device 5. Fig. 6 is a flowchart of the sterilization process, etc., performed by the spray device 5, and Fig. 7 is a diagram showing the relationship between air pressure, air flow rate, and reach distance (horizontal reach distance of water droplets) in Table 1.

[0055] Referring to FIG. 6, when spray device 5 is aimed at an object to be sprayed and spray button 33 is pressed (S0), distance measuring device 30 measures the distance between spray device 5 and the object to be sprayed (S1). The measured distance (referred to as the "measured distance") is transmitted to control device 7, and calculation unit 41 determines whether the measured distance is suitable for spraying (greater than a stored lower limit and less than a stored upper limit) (S2, S3). The "measured distance d" used for the determination by calculation unit 41 is the value actually measured by distance measuring device 30 minus the distance between distance measuring device 30 and the spray nozzle of two-fluid nozzle 11. The "suitable distance for spraying" refers to a range of 0.6 to 0.85 m, which is half of the reach distance of 1.2 to 1.7 m (see Table 1) under spray conditions d to f, at which the sterilization effect for E. coli is rated "good" in Table 2 and the deodorizing effect is rated "good" in Table 3.

[0056] Under each of the spray conditions d to f, by moving the object to be treated away from the spray device 5 by half the reach of each water droplet, it is possible to reduce wetting of the object to be treated by the spray.

[0057] If the measured distance d is less than the lower limit (0.6 m) (YES in S2), the calculation unit 41 turns on the red light 39 (S3). If the measured distance d exceeds the upper limit (0.85 m) (YES in S3), the calculation unit 41 flashes the red light 39 (S6). The person operating the spray device 5 (hereinafter referred to as the "operator") should move the spray device 5 away from the object to be sprayed when the red light 39 turns on, and move the spray device 5 closer to the object to be sprayed when the red light 39 flashes. The lighting or flashing of the red light 39 serves as an indicator to the operator that the measured distance d has been optimized.

[0058] If calculation unit 41 determines that measured distance d is equal to or greater than the lower limit and equal to or less than the upper limit (NO in S2 and S5), it calculates the drive voltage of air pump 26 and the drive voltage of ozone generator 27 according to measured distance d (S8), and operates them at the respective drive voltages to spray from two-fluid nozzle 11. The green light remains lit during spraying, informing the operator that the distance between spray device 5 and the target object is within the appropriate range.

[0059] While the spray button 33 is pressed, the distance between the spray device 5 and the object is constantly measured, and if the position of the spray device 5 changes and the measured distance d falls outside the appropriate range, the calculation unit 41 turns on or flashes the red light 39, stops spraying, and turns off the green light 40 (S4).

[0060] In addition, "Stop spraying, turn off the green light" in S4 of Figure 6 means "Do not spray, turn on the green light" "Red light off" in S7 also means "red light not on." Also, "spray, green light on" in S8 also means "spray, green light on."

[0061] When the spray button 33 is released from being pressed (S9), the calculation unit 41 stops the supply of power to the air pump 26, ozone generator 27, etc., and ends the spraying operation.

[0062] Next, calculation of the drive voltage of the air pump 26 and the drive voltage of the ozone generator 27 according to the measured distance d when the spray device 5 sprays will be described.

[0063] These calculations are performed using the following parameters, which are calculated in advance and stored in the storage unit 42: (a) Relationship between the motor drive voltage and the discharge air pressure in the air pump 26 (as a function) (b) Relationship between supply voltage and amount of ozone generated in ozone generator 27 (as a function) is used by the calculation unit 41.

[0064] From FIG. 7, it can be seen that the two-fluid nozzle 11 used in the spray device 5 has a correlation of equation (1) between the air pressure and the water droplet reach distance. logP=-0.4795×D^2+2.019×D+0.5728 (1) P: Air pressure (kPa) D: Horizontal reach (m)

[0065] Calculation unit 41 of spray device 5 substitutes twice the measured distance d measured by distance measuring device 30 for D in equation (1) to calculate the air pressure P of air pump 26 during operation that is appropriate for spraying on an object that is the measured distance d away. The pressure of the air discharged by air pump 26 correlates with the rotation speed of the motor that drives it, and the rotation speed of the motor correlates with the drive voltage. Therefore, from the relationship between the drive voltage of the motor that drives air pump 26 and the discharge air pressure stored in memory unit 42, calculation unit 41 can determine the drive voltage of air pump 26 that is appropriate for spraying when the horizontal reach distance D is twice the measured distance d (S8).

[0066] Considering that spray device 5 is used in a living space, it is preferable that the concentration of ozone gas emitted by spray device 5 is equal to or less than the allowable value (0.1 ppm). Therefore, control device 7 of spray device 5 increases or decreases the amount of ozone generated by ozone generator 27 depending on the amount of air discharged (sometimes referred to as the "discharge amount") from air pump 26 (the level of air pressure P) so that the ozone gas concentration in the air to be sprayed does not exceed the allowable value (for example, maintaining the ozone gas concentration of the air supplied to bi-fluid nozzle 11 at 0.1 ppm or less).

[0067] As shown in FIG. 7, the discharge rate of the air pump 26 is correlated with the air pressure as shown in equation (2), and once the air pressure P is determined using equation (1), the discharge rate Q of the air pump 26 can be calculated. logP=-0.02291×Q^2+0.3445×Q+1.412 (2) P: Air pressure (kPa) Q: Discharge amount (Nl / min)

[0068] That is, equation (2) presents the discharge volume Q of air pump 26 that is appropriate for the measurement distance d measured by distance measuring device 30. There are two solutions for the discharge volume Q in equation (2) using the air pressure P calculated by equation (1), but calculation unit 41 adopts one of the discharge volumes Q that takes into account the range of the discharge capacity of air pump 26 (see air volume in Table 1). (For example, when the discharge pressure of the air pump 26 is found to be 300 kPa in equation (1), the discharge rate Q, which is the solution to equation (2), is 4.35 Nl / min and 10.7 Nl / min, but from Table 1, 4.35 Nl / min is adopted as the discharge rate Q.)

[0069] The amount of ozone generated by the silent discharge ozone generator 27 has a positive correlation with the magnitude of the discharge power (the applied voltage) (for example, Norikazu Tabata and Shigenori Yagi, Ozone Generation Characteristics of Silent Discharge Ozonizers, Transactions of the Institute of Electrical Engineers of Japan, B, February 1976, pp. 43-50, URL: https: / / www.jstage.jst.go.jp / article / ieejpes1972 / 96 / 2 / 96_2_43 / _pdf).

[0070] From this, if the correlation between the amount of ozone generated by the ozone generator 27 and the voltage applied to the ozone generator 27 is expressed in advance as a function with the supply voltage as the independent variable and the amount of ozone generated as the dependent variable ((b)), it is possible to calculate the amount of ozone generated to make the ozone gas concentration a set value when the discharge amount Q is calculated using equation (2).

[0071] The calculation unit 41 determines the supply voltage to the ozone generator 27 from the value of the amount of ozone generated obtained using (a) and (b) described above, and sends power to the ozone generator 27 to spray ozone gas and water (S8).

[0072] The control of the power for driving the air pump 26 and the ozone generator 27 by the calculation unit 41 is performed by PWM (Pulse Width Modulation).

[0073] The quadratic coefficients, linear coefficients, and constants in the quadratic expressions on the right-hand sides of the above equations (1) and (2) are values ​​specific to the two-fluid nozzle 11 (model number MF008 manufactured by Nozzle Network Co., Ltd.) of the spray device 5. For other two-fluid nozzles, the coefficients and constants of equations (1) and (2) can be determined by conducting a similar preliminary study as for the two-fluid nozzle 11.

[0074] In the spraying device 5, the discharge pressure of the air pump 26 is controlled so that the average particle size of the droplets in the ozone fog sprayed by the two-fluid nozzle 11 is maintained at 4.7 to 9.3 μm, which is effective for sterilization and deodorization. The spraying device 5 can notify the operator of the appropriate distance at which wetting of the object to be treated can be reduced by flashing the red light 39 and the green light 40.

[0075] The sprayer 5 creates a veil effect by enveloping the ozone gas with mist-like water, resulting in almost no excess diffusion of ozone, enabling efficient and safe deodorization and sterilization. Because the mist-like water generated by the sprayer 5 is fine (average particle size: 4.7-9.3 μm), the overall surface area of ​​the ozone fog is large, allowing more ozone to dissolve in the water and promoting the generation of OH radicals. The fine droplets vaporize immediately after reaching the object to be treated, reducing wetting of the object.

[0076] When the spray device 5 is used outdoors or indoors with sufficient ventilation, the amount of ozone generated by the ozone generator 27 does not change even if the driving voltage of the air pump 26 changes, and the ozone generator 27 can be operated under the conditions specified by the manufacturer.

[0077] Other two-fluid nozzles can be used in the spray device 5. Even in such cases, it is appropriate to set the average droplet size of the sprayed ozone fog to 4.7 to 9.3 μm. To achieve an average droplet size of 4.7 to 9.3 μm when using other two-fluid nozzles, the air pressure is likely to be different from the values ​​in conditions d to f in Table 1. Even so, by knowing the reach of the ozone fog for each average droplet size of 4.7 to 9.3 μm, it is possible to achieve both sterilization and deodorization effects and the effect of reducing wetting.

[0078] In addition, the spray device 5 and each component or the overall structure, shape, dimensions, number, material, etc. of the spray device 5 can be modified as appropriate in accordance with the spirit of the present invention. [Industrial Applicability]

[0079] The present invention can be used for sterilization and deodorization treatment using ozone gas. [Explanation of symbols]

[0080] 5. Spraying equipment (ozone and water spraying equipment) 7 Control Device 11 Two-fluid nozzle 26 Air Pump 27 Ozone Generator 30 Distance measuring device (distance measuring device) 32 water container

Claims

1. A method for spraying ozone-containing air and water using a two-fluid nozzle, comprising: The pressure of the air supplied to the two-fluid nozzle is adjusted to set the Sauter mean particle size of the sprayed water to 4.7 to 9.3 μm. A method for spraying ozone-containing air and water, comprising:

2. The distance between the two-fluid nozzle and the object to be sprayed is measured, and the pressure of the air is adjusted based on the measured distance. The method for spraying ozone-containing air and water according to claim 1.

3. The amount of ozone is adjusted based on the amount of air supplied to the two-fluid nozzle at the adjusted air pressure. The method for spraying ozone-containing air and water according to claim 2.

4. A two-fluid nozzle; an air pump for supplying pressurized air to the two-fluid nozzle; a water container for supplying water to the two-fluid nozzle; an ozone generator that generates ozone from the compressed air before it is supplied to the two-fluid nozzle; a distance measuring device for measuring the distance between the two-fluid nozzle and an object to be sprayed; a control device having a calculation function, The control device an appropriate pressure of the pressurized air is calculated based on the distance from the distance measuring device, and an operation of the air pump is controlled so that the pressurized air has the appropriate pressure; The water sprayed from the two-fluid nozzle has a Sauter mean particle size of 4.7 to 9.3 μm. A spray device characterized by:

5. The control device The apparatus is configured to calculate the amount of air discharged from the air pump from the appropriate pressure, and to control the operation of the ozone generator so that the ozone concentration in the air discharged from the two-fluid nozzle reaches a specific concentration.

5. The spray device of claim 4.

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