Highly efficient generation of vapor-containing aerosol mist without heating

Abstract

The present invention relates to an apparatus and method for highly efficient generation and emission of an at least partially evaporated aerosol mist from a sterilizing solution without the application of heat, and is particularly suited for generating hydrogen peroxide vapor.

Description

[Technical field]

[0001] The present invention relates to an apparatus and method for generating and emitting a vapor-containing aerosol mist generated from a sterilizing solution at ambient temperature, and in particular, the apparatus and method are suitable for generating hydrogen peroxide vapor. [Background technology]

[0002] When cleaning and disinfecting areas where high purity is required, such as hospitals or the food and beverage industry, the focus is usually on visible surfaces. However, many pathogens can be airborne and end up on hard-to-reach surfaces and in air ducts. Therefore, wiping visible surfaces with disinfectants is not enough. Therefore, steam or spray for sterilization or disinfection has been developed. For example, US Patent Application Publication No. 2004 / 005240 describes the generation of a sterilizing mist in which a sterilizing solution is released in the form of droplets.

[0003] In general, vapors are slower than liquids (oxidizers in particular can cause corrosion or bleaching in the liquid phase), and vapors are also more mobile and reach the bottom surface more efficiently than liquid droplets.

[0004] CN111658803 describes a cavity for sterilizing objects placed within it using a rapidly evaporating hydrogen peroxide spray that is released directly onto the object. However, small droplets evaporate easily, while larger droplets do not. They may also act as seed droplets for the steam to recondense, making steam generation less efficient, and larger droplets emerging from the generator may accumulate on surfaces, creating a risk of corrosion or bleaching.

[0005] In steam generation, most techniques use heat to vaporize the sterilant solution, however heating can decompose the sterilant, this is known to happen, for example, with hydrogen peroxide.

[0006] Such heat-induced steam generation for disinfection purposes is described, for example, in DE 10 2008 050 947 A1. Hydrogen peroxide droplets are fed into a heated container from the top of the container using a pump and are vaporized by a stream of preheated air that is blown onto the droplets, the heat of which causes evaporation of the entire size spectrum of the droplets.

[0007] Thus, new techniques are needed to generate steam from sterilizing solutions and release said steam into the space being sterilized, disinfected, or decontaminated. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] China Patent Application Publication No. 111658803 [Patent Document 2] DE 102008050947 A1 [Patent Document 3] US Patent Application Publication No. 2004 / 005240 Summary of the Invention [Problem to be solved by the invention]

[0009] The invention is defined by the features of the independent claims. Some particular embodiments are defined in the dependent claims.

[0010] According to a first aspect of the present invention, an apparatus and method are provided for generating and emitting an at least partially evaporated aerosol mist from a sterile solution.

[0011] According to a second aspect of the present invention, an apparatus and method for generating and emitting a vapour-containing mist at ambient temperature is provided.

[0012] To achieve efficient evaporation of the sterilizing solution, the device includes a means for separating larger droplets of the sterilizing solution from the mist formed, thereby allowing only a fine mist containing small droplets to continue to exit the device.

[0013] Similarly, the present invention relates to a method for producing and releasing such a vapor, including the separation of the smallest droplets of sterilizing solution from the mist described above.

[0014] Using the invention, several advantages are achieved, among others, the largest droplets of sterilizing solution are separated, allowing steam to be generated without the application of heat.

[0015] Providing a mist of only small droplets remaining means that evaporation is more efficient and there are no seed droplets to cause re-condensation. A further advantage of the present invention is that steam can be generated in a gentler manner compared to conventional techniques, without risking decomposition of the sterilant. With no heating and no extensive evaporation control, the device can also be easier to maintain than larger commercial units.

[0016] When using a hydrogen peroxide-based sterilizing solution, an added benefit is that a sterilizing mist is produced that does not leave behind harmful chemical residues. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 illustrates a diagram of an apparatus according to at least some embodiments of the present invention, where the dotted arrows represent the flow of gas, solution, or mist.

[0018] [Figure 2A] 1A-1D show the structure of the device with different atomizers according to some preferred embodiments of the present invention. [Figure 2B] 1A-1D show the structure of the device with different atomizers according to some preferred embodiments of the present invention.

[0019] [Diagram 3] FIG. 13 shows the structure of an apparatus with a preferred solution supply system according to another embodiment of the present invention.

[0020] [Figure 4A] 13A-13D show the structure of an apparatus with an alternative droplet separation unit according to some further embodiments of the present invention. [Figure 4B] 13A-13D show the structure of an apparatus with an alternative droplet separation unit according to some further embodiments of the present invention. [Figure 4C] 13A-13D show the structure of an apparatus with an alternative droplet separation unit according to some further embodiments of the present invention.

[0021] [Diagram 5] FIG. 1 shows the structure of an apparatus representing an arbitrary gas distributor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] [Definition] In this context, the term "aerosol" is intended to encompass a suspension of fine droplets in a gas. While suspended in a flowing gas, it forms a mist that can be sprayed, for example, into an area to be decontaminated. Furthermore, the small size of the fine droplets of the mist allows at least a portion of the droplets to evaporate. The term "fine droplets" of mist is intended to define droplets that have a sufficiently small inertia to be carried along the trajectory of the gas flow even if the gas flow changes direction. Typically, such small mist droplets have a diameter of less than 10 μm, preferably less than 5 μm, and provide a sharp surface curvature that promotes evaporation.

[0023] The present invention therefore relates to an apparatus for generating and emitting an at least partially evaporated aerosol mist from a sterile solution (see FIG. 1), typically operating at ambient temperature, which apparatus is formed of a container comprising: a reservoir 1 for holding a sterile solution; a gas inlet 2 for conveying a gas flow into the vessel; a spray unit 3 for forming an aerosol mist from a sterile solution; an optional supply system 4 for supplying the spray unit 3 with a sterile solution; a mist outlet 5 for directing the formed mist containing steam out of the container; Equipped with.

[0024] As shown in FIGS. 2A and 2B, the spray unit 3 typically includes one or more of the following: one or more mist nozzles positioned to mix a high velocity jet of the generated gas stream with the sterilizing solution or to receive the sterilizing solution pumped through the nozzle at high pressure (see FIG. 2A); One or more vibrating openings, or One or more ultrasonic nebulizers (see Figure 2B) or one or more of these nebulizers Equipped with.

[0025] In one embodiment of the present invention, the spray unit 3 is a mist nozzle with an outlet width of 0.01 mm-10 mm, preferably 0.2 mm-3.0 mm, more preferably 0.5 mm-1.5 mm.

[0026] As mentioned above, the device may optionally comprise a supply system 4 for supplying sterile solution from the reservoir 1 to the spray unit 3 . This supply system 4 is one or more vacuum emitters arranged to transport the sterilizing solution from the reservoir 1 through the liquid channel to the spray unit 3 by the Venturi effect (see FIG. 3 ); one or more liquid pumps arranged to pump the sterilizing solution from the reservoir 1 through the liquid channel to the spray unit 3; or A liquid channel arranged to supply sterilizing solution by gravity from an elevated reservoir 1 to a spray unit 3 The form may consist of:

[0027] However, if the apparatus comprises a spray unit 3 that is immersed in a reservoir 1 containing the sterilizing solution, such as an ultrasonic sprayer, a separate supply system 4 is not required.

[0028] In addition to the above, the apparatus comprises an inertial separation unit 6 (see Figures 4A-4B) arranged to collide some of the aerosol droplets against a surface, such as the surface of the wall of the container (see Figure 4A), thereby separating the colliding droplets from the aerosol.

[0029] Some of the droplets that separate from the mist are usually the largest droplets, which are too heavy to change direction when confronted with a surface, leaving only small droplets in the mist that evaporate easily.

[0030] In one embodiment of the invention, the inertial separation unit 6 is in the form of an impactor, such as an impactor with an impacted target (see FIG. 4B) or a cyclone separator (see FIG. 4C), preferably in the form of an impacted target located on the trajectory of the gas flow passing through the spray unit 3, thereby causing the impact of large droplets of the solution against said target and causing their atomization or return to the reservoir 1.

[0031] In particular, the inertial separation unit 6 is in the form of an impaction target and is positioned at a distance of 0.1-10 times the width of the outlet from the outlet of the spray unit 3, preferably at a distance of 1-4 times the width of the outlet, and more preferably at a distance of 1.5-2.5 times the width of the outlet.

[0032] To facilitate droplet separation, the spray unit 3 may further be positioned vertically at the level of, or preferably below, the mist outlet 5 to prevent relatively large droplets from being discharged from the mist outlet 5.

[0033] Furthermore, in a preferred embodiment of the present invention, the gas inlet 2 and the mist outlet 5 may be positioned at an angle to each other so that the mist mixed with the gas flow changes direction within the vessel. Thus, larger droplets will impact the vessel surface, while smaller droplets will change direction and be carried along with the gas flow to the mist outlet 5. therefore, Arranging the gas inlet 2 to create a gas flow trajectory through the gas inlet 2 having a first direction; Positioning the mist outlet 5 to create a gas flow trajectory through the mist outlet 5 having a second direction; Limiting the angle between the first direction and the second direction to between 60°-120°; It is therefore preferable that the larger droplets are directed towards the wall of the container and returned to the reservoir 1 rather than being discharged through the mist outlet 5.

[0034] As shown in FIG. 5, the gas inlet 2 may further be arranged in fluid communication with a gas distributor 7, preferably in the form of a gas pressurizer, fan or blower, more preferably in the form of a gas pump, compressor or a container holding pressurized gas, most suitably in the form of a compressed or liquefied gas cylinder.

[0035] The preferred means for supplying pressurized gas is useful when a high velocity gas stream is used to evaporate the droplets.

[0036] In an alternative embodiment, when pressurized gas is used, the apparatus may also include a separate inlet for flushing gas, which generates an additional gas flow into the vessel, thereby facilitating the evacuation of the generated mist and facilitating the spreading and evaporation of the droplets in the gas flow exiting the mist outlet 5.

[0037] Since many sterilizing solutions are composed of highly reactive agents, such as strong oxidizing agents, the devices are usually made of durable materials that are not affected by the sterilizing solutions. Preferred materials are plastic, glass, or metal, and more preferred materials are plastic or glass. For example, when using sterilizing solutions that contain hydrogen peroxide, it is preferable to avoid metal.

[0038] The device of the present invention can be used, for example, in the method of the present invention, which is also intended to generate and emit an aerosol mist of at least partially evaporated sterilizing solution at ambient temperature. directing a gas flow into a container containing a sterilizing solution; directing the gas flow through the container to a spray unit 3; Providing a sterile solution to the spray unit 3, optionally using a separate step of supplying the sterile solution to the spray unit 3; spraying a sterilizing solution into the spray unit 3, thereby forming an aerosol mist comprising droplets of at least partially evaporated solution; directing the formed aerosol mist together with the gas flow out of the container via the mist outlet 5, where any fine mist droplets that may remain continue the evaporation process at high speed; Includes.

[0039] The gas used in the method may be any gas, preferably an inert gas, more preferably a gas selected from nitrogen, carbon dioxide, oxygen, argon, or air.

[0040] The aerosol mist, which is carried to the mist outlet 5 with the aid of a gas flow, is formed by atomizing the solution into fine droplets, preferably by driving the liquid solution through one or more mist nozzles where the liquid solution is mixed with a high velocity jet of the produced gas stream; By pumping a liquid solution at high pressure through one or more mist nozzles, by driving the liquid solution through one or more vibrating apertures; or By using one or more ultrasonic nebulizers, or two or more of these alternatives at the same time, is formed.

[0041] As mentioned above, the sterilizing solution may be optionally supplied to the spray unit 3 in a separate supply step, although this supply can be omitted when the spray unit 3 is immersed in the sterilizing solution. If used, the separate supply of sterilizing solution can be performed by the following steps: using one or more vacuum emitters that transfer the sterilizing solution by negative pressure created by the Venturi effect; Pumping the sterile solution using one or more liquid pumps; or Using gravity to deliver the sterile solution; It can be done by:

[0042] The method of the present invention is characterized by separating a portion of the droplets of the sterilizing solution from the gas stream by impaction, preferably by impacting the droplets against a surface of a container, such as the surface of a wall of the container, or by impacting the droplets against the surface of an impaction target, whereby the impacted droplets are separated from the gas stream.

[0043] Generally, the largest droplets impact a surface and are separated from the gas flow or atomized into smaller droplets, so that the aerosol mist carried with the gas flow to the mist outlet 5 contains only relatively small droplets, which easily evaporate at ambient temperature.

[0044] Liquid from the largest droplets that are separated from the gas stream is preferably returned to solution in the vessel.

[0045] In a preferred embodiment, droplet separation is performed using inertial separation, more preferably using an impactor or cyclone separator, most suitably using an impacted target positioned within the trajectory of the high velocity gas stream. Typically, large droplets of solution captured by the gas stream are positioned to impact the target and be atomized into smaller droplets or returned to the solution reservoir 1 from which the solution can be reused.

[0046] Separation of some of the droplets can also be promoted by positioning a mist outlet 5 within the vessel at a location which forces a change in the direction of the gas flow within the vessel, causing larger droplets to inertially separate from the mist-laden stream.

[0047] For example, large droplets can be separated from the mist by arranging the gas inlet 2 and the mist outlet 5 at an angle to each other. This forces the trajectory of the gas flow from the gas inlet 2 to the mist outlet 5 to bend. A suitable angle is 60 degrees to 120 degrees. This causes the relatively large droplets to be directed towards the wall of the container instead of being released from the mist outlet 5.

[0048] Using one or more of these techniques, a portion of the droplets is separated from the gas stream and the diameter of the droplets in the formed aerosol mist is typically limited to droplet diameters <10 μm, preferably droplet diameters <5 μm, by separation of a portion of the droplets that comprises the largest droplets of the mist.

[0049] Due to the small size of the droplets remaining in the mist, evaporation occurs spontaneously, resulting in a mist containing vapor. Evaporation is enhanced by the sharp surface curvature of these small droplets.

[0050] As mentioned above, the gas used in this method can be any suitable gas, in particular the gas can be selected from nitrogen, carbon dioxide, oxygen, argon or air, or another suitable gas, preferably air.

[0051] In those embodiments requiring high gas flow, the gas is preferably supplied at high pressure, such as a pressure above 1 bar, more preferably at a pressure between 2 bar and 10 bar. One alternative is to use a separate flushing gas to facilitate carrying the formed mist out of the vessel. The gas can be selected from the list of gases above.

[0052] The sterilizing solution can be selected from any solution containing one or more sterilants that is sufficiently volatile to evaporate from small droplets at ambient temperature. Depending on the sterilizing agent selected, it can be used as a 100% solution of the sterilizing agent or it can be diluted with water or other solvents. A preferred sterilizing agent is an aqueous solution of hydrogen peroxide, which may be mixed with additives such as ammonia or acetic acid.

[0053] The gases may also be mixed with additives such as ozone, ethylene oxide, ammonia, chlorine, chlorine dioxide, nitrogen dioxide, etc. to further enhance and synergize the sterilization process.

[0054] In a preferred embodiment, the sterilization solution is a solution of hydrogen peroxide in water, preferably at a concentration of 1 vol-%-100 vol-% hydrogen peroxide, more preferably at a concentration of 30 vol-%-75 vol-% hydrogen peroxide, even more preferably at a concentration of 30 vol-%-65 vol-% hydrogen peroxide, and most preferably at a concentration of 35 vol-%-50 vol-% hydrogen peroxide, and in such a manner that hydrogen peroxide vapor is produced.

[0055] One alternative is also to add acetic acid to the preferred hydrogen peroxide solution, in particular at a concentration of up to 10% by weight, preferably up to 7% by weight, and most suitably at a concentration of about 5% by weight.

[0056] The above-mentioned device and method are suitable for use in enclosed spaces such as rooms or air ducts, for example, when disinfecting or decontaminating air and surfaces within a target volume. In such applications, the mist of the present invention is sufficient at low concentrations, for example, at a concentration of 150 ppm-1000 ppm, and the mist is allowed to react for more than 5 minutes, preferably more than 1 hour.

[0057] It is to be understood that the disclosed embodiments of the invention are not limited to the particular structures, process steps, or materials disclosed herein, but extend to equivalents thereof as recognized by those skilled in the relevant art. It is also to be understood that the terminology used herein is used only for the purpose of describing particular embodiments, and is not intended to be limiting.

[0058] Reference to an embodiment throughout this specification means that the particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment of the present invention. Thus, the phrases "in one embodiment" or "in an embodiment" appearing in various places throughout this specification do not necessarily all refer to the same embodiment. For example, when referring to a numerical value using terms such as about or substantially, the exact numerical value is also disclosed.

[0059] As used herein, a plurality of items, structural elements, components, and / or materials may be presented in common lists for convenience. However, these lists should be construed as though each element of the list is individually identified as a separate and unique element. Additionally, various embodiments and examples of the invention may be referenced herein along with alternatives for the various components thereof. It is understood that such embodiments, examples, and alternatives should not be construed as de facto equivalents of one another, but should be considered as separate and autonomous manifestations of the invention.

[0060] Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In this description, numerous specific details are provided to provide a thorough understanding of embodiments of the invention. However, one skilled in the art will recognize that the invention may be practiced without one or more of the specific details.

[0061] While the foregoing examples illustrate the principles of the invention in one or more particular applications, it will be apparent to those skilled in the art that many modifications in form, use, and details of implementation can be made without the exercise of inventive faculty and without departing from the principles and concepts of the invention. Accordingly, it is not intended that the invention be limited, except as by the scope of the claims which follow. [Industrial Applicability]

[0062] The devices and methods of the present invention can be used for highly efficient generation of steam without adding heat, and can generally be used as a replacement for conventional devices for producing and emitting mist containing vapors of various sterilizing solutions. [Explanation of symbols]

[0063] 1 Reservoir 2 Gas inlet 3 Spray unit 4. Optional Supply System 5 Mist Exit 6 Inertial Separation Unit 7 Gas distributor

Claims

1. 1. An apparatus for generating and emitting an at least partially evaporated aerosol mist from a sterilizing solution, comprising: The apparatus comprises: a reservoir (1) for holding said sterilizing solution; a gas inlet (2) for conveying a gas flow into the vessel; a spray unit (3) for forming an aerosol mist from the sterilizing solution; an optional supply system (4) for supplying the sterilizing solution to the spray unit (3); a mist outlet (5) for directing the formed steam-containing mist out of the container; The present invention is formed of a container comprising: The apparatus comprises: an inertial separation unit (6) arranged to cause a portion of the droplets of the aerosol to impact against a surface of the container and separate the impacted droplets from the aerosol; Further equipped with The inertial separation unit (6) in the form of an impaction target, which is positioned on the trajectory of the gas flow passing through said spray unit (3) at a distance from the outlet of said spray unit (3) of 1 to 4 times the width of said outlet; An apparatus comprising:

2. The spray unit (3) comprises: one or more mist nozzles positioned to mix the high velocity jet of the generated gas stream with the sterilizing solution or to receive the sterilizing solution pumped through a nozzle at high pressure; one or more vibrating apertures, or one or more ultrasonic nebulizers; Contains one or more of the following:

2. The apparatus of claim 1.

3. The spray unit (3) comprises: A mist nozzle having an outlet width of 0.01 mm to 10 mm, preferably 0.2 mm to 3.0 mm, more preferably 0.5 mm to 1.5 mm; 2. The apparatus of claim 1.

4. The impaction target comprises: Located at a distance of 1.5-2.5 times the width of the outlet of the spray unit (3); 2. The apparatus of claim 1.

5. The apparatus comprises: one or more vacuum emitters arranged to transport sterilizing solution from said reservoir (1) through a liquid channel to said spray unit (3) by Venturi effect; one or more liquid pumps arranged to pump the sterilizing solution from the reservoir (1) through a liquid channel to the spray unit (3); or a liquid channel arranged to supply the sterilizing solution by gravity from the elevated reservoir (1) to the spray unit (3); It consists of: a supply system (4) for supplying the sterilizing solution to the spray unit (3), 2. The apparatus of claim 1.

6. The apparatus comprises: a spray unit (3) immersed within the reservoir (1) containing the sterilizing solution, whereby a separate supply system (4) is not required; 2. The apparatus of claim 1.

7. Made from durable materials, Preferred materials are plastic, glass, or metal; More preferred materials are plastic or glass.

2. The apparatus of claim 1.

8. The gas inlet (2) is in fluid communication with a gas distributor (7); Preferably in the form of a gas pressurizer, fan or blower; More preferably, in the form of a gas pump, compressor, or container for holding pressurized gas; Most suitably in the form of a compressed gas bottle.

2. The apparatus of claim 1.

9. 1. A method for generating and emitting an at least partially evaporated aerosol mist from a sterilizing solution at ambient temperature, comprising: directing a gas flow into a container containing a sterilizing solution; directing the gas flow through the vessel to a spraying unit (3); Providing a sterilizing solution to the spray unit (3); spraying said sterilizing solution into said spray unit (3), thereby forming an aerosol mist comprising at least partially evaporated liquid droplets; directing the formed aerosol mist together with the gas flow out of the container via a mist outlet (5); Including, Separating a portion of droplets of the sterilizing solution from the gas flow by collision with an impaction target located on the trajectory of the gas flow passing through the spray unit (3) at a distance from the outlet of the spray unit (3) that is 1 to 4 times the width of the outlet, thereby separating the impacted droplets from the gas flow carried to the mist outlet (5). A method comprising:

10. The aerosol mist is formed by atomizing the solution; Preferably, driving the solution through one or more mist nozzles to mix the solution with high velocity jets of the generated gas stream; by pumping the solution at high pressure through one or more mist nozzles; by driving the solution through one or more vibrating apertures; or By using a separate ultrasonic nebulizer, or by using two or more of these alternatives simultaneously, is formed, 10. The method of claim 9.

11. The gas is nitrogen, oxygen, carbon dioxide, argon, or air; 10. The method of claim 9.

12. The gas may include, as an additive, containing ozone, ethylene oxide, ammonia, chlorine, chlorine dioxide, or nitrogen dioxide; 10. The method of claim 9.

13. The sterilizing solution comprises: using one or more vacuum emitters that transport the sterilizing solution by the Venturi effect; pumping the sterilizing solution using one or more liquid pumps; or using gravity to deliver the sterilizing solution; to the spray unit (3) in a separate supply step, 10. The method of claim 9.

14. Some of the droplets of sterilizing solution are separating a portion of the droplets from the gas stream by impacting them against a surface, preferably either a surface of the container or a surface of an impacted target; the impacted droplets are the largest droplets of the solution, thereby causing either atomization of these impacted droplets or return of the solution into the vessel; 10. The method of claim 9.

15. The diameter of the droplets in the formed aerosol mist is The separation of a portion of the droplets, including the largest droplets of the mist, limits the droplet diameter to <10 μm, preferably <5 μm; 10. The method of claim 9.

16. said sterilization solution is preferably a solution of hydrogen peroxide in water at a concentration of 1%-100% by volume, more preferably at a concentration of 30%-75% by volume, even more preferably at a concentration of 30%-65% by volume, most suitably at a concentration of 35%-50% by volume, by which hydrogen peroxide vapour is formed; 10. The method of claim 9.

17. Disinfect or decontaminate the air and surfaces within the target volume; Use of a device according to any one of claims 1 to 8 or a method according to any one of claims 9 to 15.

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