GB2608582A

GB2608582A - Disinfection apparatus

Info

Publication number: GB2608582A
Application number: GB2105323.6A
Authority: GB
Inventors: Turner Colin
Original assignee: Dantech Uk Ltd
Current assignee: Dantech Uk Ltd
Priority date: 2021-04-14
Filing date: 2021-04-14
Publication date: 2023-01-11
Also published as: GB202105323D0

Abstract

A disinfecting apparatus 10 comprising a housing 12 through which items to be disinfected 14 pass on a conveyor means 16. The apparatus 10 further comprises a first tank containing a disinfecting liquid, a pump and tube means for pumping the disinfecting liquid from the first tank to one or more nozzles 24, and a drip tray 38 within the housing 12. The drip tray 38 has an outlet 40 that decants the collected overspray and run-off disinfecting liquid into a recovery tank 42. The nozzles 24 comprise fogging nozzles which disperse the disinfecting liquid towards the items to be disinfected 14 from above, from either side and from below. The conveyor means 16 is perforated, apertured or reticulated such that items to be disinfected 14 placed thereon are exposed to at least one nozzle 24 capable of creating a fog of disinfecting liquid from below. In one embodiment, the conveyor means comprises a plurality of motor-driven conveyor belts (19, fig. 2) with a gap (22, fig 2) between the end of one conveyor belt and the start of an adjacent conveyor belt, with at least one fogging nozzle 24 located within the gap (22, fig. 2).

Description

DISINFECTION APPARATUS

This invention relates to disinfection apparatus, and in particular, but without limitation, to disinfection apparatus suitable for disinfecting trays and other objects.

In the light of the COVID-19 pandemic, the security trays used at airports have been identified in various reports as posing a significant cross-contamination and cross-infection risk due to them being "concentrated touch points". At present, users place their belongings in the trays, which pass through an x-ray machine on a conveyor, and once emptied, the tray is simply returned to the start of the conveyor.

Due to the large numbers of people who touch the trays every day, and by virtue of the fact that most of the touching takes place around the rim of the tray, the tray rims in particular present a significant risk for self-inoculation. The same concerns as above apply to warehouse tray/bin systems, and also to the delivery trays used by online grocery providers, etc. Currently, there is no effective or efficient way to sanitise or disinfect trays such as those mentioned above before each use owing to their size, complex geometry and the fact that, in an airport, for example, up to a hundred or so trays may be used per minute, per security station. This results in every-use disinfection of the trays being impractical. As a result, the trays are usually only cleaned during down-times of the security station.

It is also self-evident that systematic cleaning of other "handled" or "hand-held" items, such as post/mail/packages, reusable cutlery and crockery in food outlets; testers, try-ons and samples in shops etc. is also problematic for the same reasons as mentioned above.

Nevertheless, automated cleaning systems do exist, and these are often used in the poultry and food packing industries where packaging needs to be disinfected against bacteria and the like. These typically comprise a conveyor system, which enables the items to be sanitised to be placed thereon and conveyed through a spraying system, which sprays a disinfectant liquid onto the objects on the conveyor. During the dwell time of the disinfectant liquid on the objects to be sanitised, disinfection occurs and this results in the packages becoming sanitised.

Known automated cleaners are disclosed in for example: KR101982787, which is directed to a hand-held device with a pump and an atomising nozzle that forms a mist of disinfection liquid.

GB2545771 is directed to a pathogen killing apparatus, which uses a hypochlorous acid mist in a tunnel for disinfecting objects placed therein. LI54999929 is directed to the combination of a hand dryer and a spray sanitiser. CN110624883, CN107504791 and CN105494146 are poultry cleaners which use conveyor systems and a series of spray nozzles located over reticulated conveyors. KR20130091883 discloses a walk-through disinfection tunnel used, for example, in clean room environments, where a user stands on a pad and is sprayed from various directions using a disinfectant sprayer. W00179791 discloses a mixer nozzle arrangement for use in disinfection where the disinfection liquid is sprayed in opposing directions so as to attain better mixing of two products.

The drawback of the prior art and the aforementioned disclosures is the fact that they rely on spraying or misting a disinfectant liquid onto the objects to be cleaned. This results in the objects becoming wet, and therefore not immediately ready for re-use. This is not necessarily a problem in a meat packing plant where several hours or days may elapse between the disinfection process and the first time the product is touched by human hand thereafter, but in the case of post, security trays and the like, which are immediately handled, this is not a viable option. In addition, the prior art does not disclose any way to address the problem of completely covering all surfaces of the items to be sanitised using a spray/mist. Indeed, as there is always contact between the conveyor system and the object to be sanitised, there is always a "mist shadow" -meaning that parts of the object are never in contact with the sanitising liquid. Moreover, the sanitisation efficacy will depend on the orientation of the items on the conveyor belt, for example, if they are upside down or the right way up, then this may result in different surfaces being sanitised.

A need therefore exists for a solution to one or more of the aforesaid problems, which the present invention aims to provide.

Aspects of the invention are set forth in the appended independent claim or claims. Preferred and/or optional features of the invention are set forth in the appended dependent claims.

A first aspect of the invention provides a disinfecting apparatus comprising: a housing with an inlet opening, an outlet opening and a conduit connecting the inlet opening to the outlet opening; conveyor means extending through the conduit upon which items to be disinfected can be placed, the conveyor means being configured to convey the items to be disinfected through the conduit from the inlet opening to the outlet opening; a first tank containing disinfecting liquid pump and tube means arranged to pump the disinfecting liquid from the first tank to one or more nozzles arranged to disperse the disinfecting liquid within the conduit towards the items to be disinfected; a drip tray within the housing arranged to collect overspray and run-off disinfecting liquid, the drip tray having an outlet arranged to decant the collected overspray and run-off disinfecting liquid into a second tank, characterised in that: the one or more nozzles comprise fogging nozzles adapted, in use, to create a fog of disinfecting liquid within the conduit; and are arranged so as to disperse the disinfecting liquid towards the items to be disinfected from above, from either side and from below; and wherein the conveyor means is perforated, apertured or reticulated such that items to be disinfected placed thereon are exposed to at least one nozzle capable of creating a fog of disinfecting liquid from below such that a surface of the items to be disinfected in contact with the conveyor means is exposed to the fog.

The housing comprises an inlet opening and an outlet opening with a conduit therebetween.

This is suitably in the form of a "tunnel" with the conveyor extending through the tunnel. This configuration will be familiar to users of the system and also lends itself to incorporation into an adjacent conveyor belt system.

The conveyor means can be of any suitable type, although it is envisaged that the conveyor means would be a driven conveyor belt system or a driven roller system. Preferably, the conveyor comprises a conveyor belt, which is reticulated or formed as a mesh so as to have a relatively open structure. This means that the contact between the item to be disinfected and the conveyor belt is minimised, and this permits the maximum possible amount of fogged disinfectant liquid to come into contact with the surfaces of the object to be disinfected.

The disinfecting apparatus has a first tank containing the disinfecting liquid and a pump and tube arrangement arranged to deliver the disinfecting liquid from the first tank into the one or more nozzles. The nozzles are arranged to disperse the disinfecting liquid towards the items to be disinfected, and this is suitably in the form of a ring or hoop of nozzles encircling the conveyor and the items to be disinfected. By arranging the nozzles in a ring surrounding the conveyor and the items to be disinfected, the fog can be introduced into the housing from several directions so as to create a homogeneous fog within the housing/conduit.

The disinfecting apparatus comprises a drip tray which is also located within the housing, and this is arranged to collect any run-off or drips of disinfecting liquid. The drip tray has an outlet connecting to the recovery tank. By collecting the run-off or overspray/drips into a separate recovery tank, this avoids recirculating the disinfecting liquid thereby maintaining a required standard of hygiene/sanitisation.

The invention is distinguished over the prior art insofar as the one or more nozzles comprise fogging nozzles. This is as opposed to spray or misting nozzles in the prior art. The essential difference is the droplets' size created by the nozzle, which in the case of a fogging nozzle is very much smaller. A fan arrangement may also be used. A fogging nozzle essentially creates an airborne suspension of liquid droplets (an aerosol), which is fine enough that it remains in suspension for a certain amount of time. Because the fog is homogeneously distributed within the housing, all surfaces of every item located within the housing come into contact with the liquid disinfectant aerosol and thus become coated therewith. This results in an even coating/distribution of the disinfection liquid over all exposed surfaces of the items to be sanitised regardless of their orientation. The interior of hollow items can also be sanitised by the invention.

This is best accomplished by providing a number of fogging nozzles within the tunnel, as opposed to spray nozzles, which create a fog of disinfectant within the tunnel. As the items pass through the tunnel, all exposed surfaces come into contact with the fog and are thereby disinfected. Moreover, because the fog droplets are sub-micron sized, their evaporation rate is extremely high, which means that the trays are completely dry, and are hence reusable, within a matter of minutes or seconds after having come into contact with the fog. In certain embodiments, the liquid is preheated before it is fogged by the fogging nozzles, and this too can contribute to increased evaporation / drying rates. Indeed, if the speed of the conveyor and/or the length of the tunnel is optimised, then the trays can exit the disinfection tunnel completely dry and immediately ready for immediate re-use.

Fogging may be assisted by fans placed strategically above and below the items passing through the conduit, so that the fog is circulated within the conduit and can impinge on the items to be disinfected from various angles..

Embodiments of the invention shall now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a schematic cross-sectional view of an embodiment of a disinfecting apparatus in accordance with the invention; Figure 2 is a schematic cross-section of another embodiment of a disinfecting apparatus in accordance with the invention.

A disinfecting apparatus 10 in accordance with the invention comprises a tunnel 12 through which items to be sanitised 14 pass. The items to be sanitised, which in the illustrated embodiment are trays 14, are moved through the tunnel 12 by a conveyor system 16. In the embodiment shown in Figure 1 of the drawings, the conveyor system 16 comprises a single reticulated conveyor belt 18, which is driven by a set of rollers 20. In the embodiment shown in Figure 2, the conveyor system 16 comprises a pair of conveyor belts 19 also driven by rollers 20. A gap 22 is present between the end of one conveyor 16 and the beginning of a second conveyor 16A, which gap 22 has both a horizontal and a vertical component in the embodiment shown.

Located within the tunnel 12 are a set of fogging nozzles 24, which are arranged around the conveyor 16 within the tunnel 12 so as to form a fog of disinfectant liquid, which is fed into the fogging nozzles 24 from a tank (not shown) via tubing and pumps (not shown for clarity). The fogging nozzles 24 produce a fog of disinfectant liquid, that is to say an aerosol suspension having a droplet size of the micrometre range, which coats all exposed surfaces of the trays 14 or other objects to be cleaned. Because the fogging nozzles 24 create a fog, as opposed to a mist or spray of disinfectant liquid, all exposed surfaces of the items to be sanitised 14 come into contact with the fog. This disinfects the coated surfaces as the items to be sanitised 14 move through the tunnel 12 on the conveyor 16. In the embodiment shown in Figure 1 of the drawings, the conveyor belt 18 is reticulated, that is to say having a wire mesh construction or an apertured web configuration, and this means that the surface area of the items to be sanitised 14 in contact with the conveyor belt 18 is minimal. This effectively means that the items to be sanitised 14 effectively "float" through the tunnel 12 and the fogging nozzles 24 are able to create a fog, which coats all of the items 14 from all directions.

It will be appreciated that even with the largest mesh size, there will always be a finite amount of the surface area of the items to be sanitised 14, which remain in contact with the conveyor belt 18. In order to ameliorate against this, the invention proposes intermittently reversing or oscillating the drive rollers 24 so as to create some slippage between the conveyor belt 18 and the items to be sanitised 14 periodically. This effectively shifts the point of contact between the conveyor belt 18 and the items 14 and means that previously in-contact regions of the surface area are now aligned with apertures of the conveyor belt 18 and are thus available to accept the fog of disinfectant liquid.

On the other hand, in the embodiment shown in Figure 2 of the drawings, the gap 22 between the conveyor belts 19 means that as the items 14 to be sanitised pass from one belt 16 to the other 16A, their undersides are effectively exposed. By placing the fogging nozzle 24 in the gap 22, this means that the surface regions of the items 14 that were previously in contact with the conveyor belt 19 are now bridging the two conveyor belts 19 and are able to be coated by the fog.

It will be appreciated that a fog of disinfectant behaves quite differently to a mist or spray insofar as it is essentially an aerosol suspension. In order that the concentration of fog remains homogeneous within the tunnel 12, it is preferred to use an air circulation system. This could be, in one embodiment, in the form of a agitator/fan located within the tunnel 12, which agitates the air within the tunnel 12, thus causing the fog of disinfectant to be circulated/re-circulated. However, by providing a positive air pressure fan within the tunnel 12, this tends to cause the disinfectant fog to be blown out through the open ends of the tunnel.

In order to ameliorate against this, it is proposed to install a curtain 26 at the opening of the tunnel 12, and this causes the fog of disinfectant liquid to be retained within the tunnel to a certain extent. An extractor fan 28 is also suitably provided, towards the exit end 30 of the tunnel 12, which draws air out of the tunnel through the fan 28, in preference to through the opening 30. A liquid recovery scrim 32 is provided at the outlet side of the fan 28, and this recovers fog/liquid 34 from the extracted air so as to prevent it from being wasted/released into the atmosphere.

In the embodiment shown in Figure 2, a drip recovery tray system 36 is provided adjacent the scrim 32 and this enables the excess liquid to be recovered without it dripping onto the items to be sanitised 14 below and re-wetting them.

The tunnel 12 has a lower wall 38 formed as an inclined plate, which collects any drips or droplets 40 and directs them into a recovery tank 42 via an outlet tube 44. This configuration means that a supply tank (not shown for clarity) can be used to supply the disinfectant liquid for the fogging nozzles 24 and another container 42 can be used to recover the excess/unused liquid from the process.

In a preferred embodiment of the invention, the disinfection apparatus 10 is battery-powered or mains-powered. A battery-powered system has the advantage of enabling the disinfection apparatus to be portable and this is even more so due to the fact that it has disinfectant liquid and recovery tanks as well. This means no dedicated plumbing or wiring needs to be provided -the device can simply be moved into position and used, with batteries, disinfectant liquid and recovery tank changes as and when needed. For more permanent installations, a mains flex could be used to power the device off a standard mains outlet socket, which are ubiquitous.

It is envisaged that the disinfection apparatus could be used either indoor or outdoors, and could even be a portable/mobile device.

The invention is not limited to the details of the foregoing embodiments, which are merely exemplary.

Claims

CLAIMS1. A disinfecting apparatus comprising: a housing with an inlet opening, an outlet opening and a conduit connecting the inlet opening to the outlet opening; conveyor means extending through the conduit upon which items to be disinfected can be placed, the conveyor means being configured to convey the items to be disinfected through the conduit from the inlet opening to the outlet opening; a first tank for containing a quantity of disinfecting liquid; pump and tube means arranged to pump disinfecting liquid from the first tank to one or more nozzles arranged to disperse the disinfecting liquid within the conduit towards the items to be disinfected; a drip tray within the housing arranged to collect overspray and run-off disinfecting liquid, the drip tray having an outlet arranged to decant the collected overspray and run-off disinfecting liquid into a recovery tank, characterised in that: the one or more nozzles comprise fogging nozzles adapted, in use, to create a fog of disinfecting liquid within the conduit; and are arranged so as to disperse the disinfecting liquid towards the items to be disinfected from above, from either side and from below; and wherein the conveyor means is perforated, apertured or reticulated such that items to be disinfected placed thereon are exposed to at least one nozzle capable of creating a fog of disinfecting liquid from below such that a surface of the items to be disinfected in contact with the conveyor means is exposed to the fog.
2. The disinfecting apparatus of claim 1, wherein the conveyor means comprises a driven conveyor belt system or a driven roller system.
3. The disinfecting apparatus of claim 1 or claim 2, wherein the conveyor means comprises a conveyor belt, which is reticulated or formed as a mesh.
4. The disinfecting apparatus of any preceding claim, wherein the nozzles are arranged as a ring or hoop of nozzles encircling the conveyor and the items to be disinfected.
5. The disinfecting apparatus of any preceding claim, wherein the first tank and/or recovery tank is removable.
6. The disinfecting apparatus of claim 5, comprising quick release couplings between the first tank and the pump and tube means, and between the outlet and the recovery tank, respectively.
7. The disinfecting apparatus of any preceding claim, wherein the conveyor means comprises a reticulated, motor-driven conveyor belt.
8. The disinfecting apparatus of any preceding claim, wherein the conveyor means comprises a plurality of motor-driven conveyor belts with a gap between the end of one conveyor belt and the start of an adjacent conveyor belt, and wherein at least one fogging nozzle is located within the gap and arranged to direct a fog of disinfectant towards a surface of an object to be disinfected bridging the gap.
9. The disinfecting apparatus of claim 8, wherein the gap has both a horizontal and a vertical component.
10. The disinfecting apparatus of any preceding claim, wherein the conveyor belt has a wire mesh construction.
11. The disinfecting apparatus of any of claims 7 to 10, wherein the motor is configured, in use, to intermittently reversing or oscillating the direction of the conveyor means to cause the items to be disinfected to slide relative to the conveyor belt.
12. The disinfecting apparatus of any preceding claim, further comprising an air agitation or circulation system located within the conduit.
13. The disinfecting apparatus of claim 12, wherein the air agitation or circulation system comprises a fan.
14. The disinfecting apparatus of claim 13, wherein the air agitation or circulation system comprises an extractor fan at or towards the outlet opening of the conduit.
15. The disinfecting apparatus of claim 14, wherein the extractor fan comprises a liquid recovery scrim to recovers fog/liquid from the extracted air.
16. The disinfecting apparatus of claim 15, wherein the extractor fan comprises a drip recovery tray system to direct recovered liquid directly or indirectly into the recovery tank.
17. The disinfecting apparatus of any preceding claim, wherein the first tank and/or the pump and tube means further comprises a heater, for pre-heating the disinfecting liquid.
18. The disinfecting apparatus of any preceding claim, wherein the disinfection apparatus is battery powered.
19. The disinfecting apparatus of any preceding claim, wherein the disinfection apparatus is mains-powered, via a flex that plugs into a standard mains outlet socket.