Technical Field

The invention relates generally to a bin lid for a waste bin. More particularly, the invention relates to a bin lid for dehydrating food and/or organic waste inside the bin.

Background

The United Nation’s Food and Agricultural Organisation (FAO) estimate that approximately one third of the world’s food is lost or wasted every year (Global Food Losses and Food Waste, Gustavsson et ah, 2011). In the UK, it is estimated post-farm gate food losses and wastage is around 9.5 million tonnes per year, of which 6.6 million tonnes or 70% is household waste. Of the 6.6 million tonnes of food waste generated in UK homes, only 20% is recycled, and of the remainder, 12% is sent to landfill, 23% ends up in our sewer system and 45% is used for thermal recovery, i.e. incineration (WRAP, 2020).. All these waste management options have negative consequences for the environment. However, through anaerobic digestion, food waste can be used as an organic fertilizer and as a clean energy source.

In the UK, many local councils across the country have tried implementing food waste collection services, where a household has a dedicated food waste bin which is collected by the council on a weekly or biweekly basis. However, participation levels in these schemes have been low and there is typically a decline in participation rates after schemes are introduced.

Studies have been conducted to identify why some households decide not to participate in food collections schemes, and why some households stop participating after an initial period. The most common reason relates to hygiene, in particular the odours and mess associated with the food collections bins (WRAP, 2016).

The UK Government is mandating that all councils should offer food waste collection services by 2023 (Defra, 2020). Therefore, it is in councils’ interest to increase participation rates in these schemes.

To try and address the problems associated with food waste, dehydrators have been used. Dehydrating food waste helps to prevent the build-up of moisture and/or residues. Most dehydrators rely on heating systems which warm up the contents of a bin and/or mechanical agitators to help aerate the contents. However, these dehydration systems, particularly heating systems, are not suitable for all types of bin, and the bins are often specifically designed to accommodate such a system. In addition, the components of these systems, e.g. heating systems, also increase the price of the bin along with its running costs, which causes people to avoid using it.

The present invention has been devised with the foregoing in mind.

Summary of Invention According to a first aspect of the invention there is provided a lid for a waste bin. The lid may be a waste bin lid. The lid may be configured to dehydrate the contents of the bin. The lid may comprise a fan, or one or more fans, configured to dehydrate contents of the bin. The fan(s) may be configured to replace air from inside the bin with air from outside the bin. The fan(s) may be configured to replace air from inside the bin (which is relatively moist compared to air outside the bin) with air from outside the bin, e.g. “fresh” air.

The lid may comprise an opening. The opening may be an opening to, or in communication with, the interior of the bin through which a flow of air can enter the bin when the lid is attached to the bin. The fan may be configured to generate a flow (i.e. an inlet flow) of air from outside the bin (and lid) through said opening into the interior of the bin. Air outside the bin and lid may be referred to as “ambient” air.

The lid may comprise an outlet, or one or more outlets, through which a flow of air from inside the bin can exit the bin (to the surroundings). The outlet may be referred to as an exhaust outlet. The exhaust outlet may connect the interior/inside of the bin to the outside/surrounding environment and provide a path for the moist air to exit the bin interior.

The fan(s) may be configured to generate a (inlet) flow of air from outside the bin (and lid) through said opening into the interior of the bin, and a (exhaust) flow out of the bin through the outlet via positive pressure created by the fan, to replace air inside the bin with air from outside the lid and bin and dehydrate the contents of the bin. The fan(s) may be configured to generate the airflow that circulates around the contents of the bin.

Dehydrating the contents of a waste bin, such as food or organic waste, provides several advantages and beneficial effects. It limits microbial growth by reducing the build-up of moisture and residues within the bin. This reduces the odour and mess associated with the bin, and can reduce the frequency in which the bin needs cleaning. In food collection bins, dehydrating the contents of the bin makes food collection schemes more appealing to a user. Dehydrating the contents of a bin can also reduce the weight and volume of bin contents. This can make it easier for a user to move the bin and provide a potential cost saving to councils. Further, improving hygiene of food waste collection may enable less frequent collections from the council, again saving potential costs.

A waste bin is typically a receptacle with an open upper end providing access to the interior/cavity of the bin which can contain waste. The lid is sized and configured to fit on or over the open/upper end of a bin. The lid may be configured to engage or be attachable to the open end of the bin. The lid may be configured to be retrofittable to a bin, i.e. to replace the bin’s original lid. For example, the lid may be configured to connect/ attach to a bin in the same way as the bin’s original lid. The lid may be detachable from, and reattachable to, the bin. The lid may be configured to attach to the bin via an engagement mechanism that engages the upper end of the bin. The engagement mechanism may be or comprise a mechanical and/or frictional engagement mechanism. The engagement mechanism may be or comprise one more clips, lips, struts, ribs, hinges, and/or retention members. Additionally or alternatively, the lid may be attachable to the bin via a hinge. The lid may be configured to connect to the bin using a quick release system. For example, the engagement mechanism may be or comprise one or more movable retention members/clips that releasably engage the upper end or rim of the bin.

Having a detachable lid enables retrofitting onto existing bins, easy and safe cleaning of the lid or bin without risk of damage, and also replacement of the lid if damaged.

At least one of the one or more fans may be a primary fan or an inlet fan. The primary /inlet fan may be coupled to, or in fluid communication with, the opening so as to direct air through the opening into the bin. The primary/inlet fan may be configured to generate an inlet flow of air from outside the bin (and lid) through said opening into the interior of the bin.

The inlet/primary fan blows ambient air from outside the bin (and lid) onto the interior of the bin to create convection currents around the waste contents and to promote evaporation. Due to the positive pressure created within the bin cavity by the air flow through the opening, the moisture contained in this air is expelled to the surrounding ambient environment via the outlet. The lid may comprise filtration system/means configured to remove particulates, odours and possible contaminants from the exhaust air flow exiting the bin though the outlet.

The opening may comprise a flow directing means, such as one or more funnels, pipes or conduits to direct the airflow from the primary fan(s) to specific points within the bin interior in order to improve the circulation of air and / or encourage evaporation of the waste products.

Multiple fans may be used to promote the extraction of the moist air within the bin interior. The lid may comprise an outlet fan. The outlet fan may be positioned in, coupled or, or in fluid communication with, the outlet to generate an exhaust flow of air out of the bin through the outlet. The outlet fan may aid extraction of air from the bin interior.

The outlet fan may be operated synchronously with the inlet fan, and/or at a speed corresponding to the inlet fan such that the exhaust flow substantially matches the inlet flow.

The fan(s) may be or comprise an axial fan or a centrifugal fan. A centrifugal fan may be more efficient and/or quieter than an axial fan. Alternatively, the fan(s) may be or comprise a conical or frustoconical impeller.

The opening and/or the outlet may comprise a nozzle to increase the inlet and/or exhaust air flow velocity. This may increase the airflow through bin interior for a given fan speed (thereby improving dehydration) and/or allow the fan to operate as a lower speed for a given target airflow speed to reduce the power consumption of the lid. The inlet nozzle may be positioned downstream of the outlet of the inlet fan. The opening may be a primary opening positioned downstream of the fan outlet, and the lid may further comprise a secondary opening adjacent the primary opening through which a secondary flow of ambient air from outside the bin (and lid) can enter the interior of the bin when the lid is attached to the bin, and wherein the secondary air flow is generated by the primary airflow exiting the nozzle. The nozzle(s) may comprise or be shaped to form a Coanda surface. The secondary air flow may be generated by the primary airflow over the Coanda surface. The Coanda surface may extend around the opening and/or the outlet.

A Coanda surface is a known type of surface over which air flow exiting an opening close to the surface exhibits the Coanda effect, whereby the “primary” airflow exiting the opening has a tendency to stay close to the surface and entrains an airflow from the surroundings so that a region of low pressure develops. In this way, an increased amount of ambient air from outside the bin/lid can be drawn into the bin.

Where the lid comprises an outlet nozzle, the outlet nozzle may be positioned downstream of the exhaust fan outlet.

The outlet(s) may be configured to direct a flow of air exiting the bin in a substantially downward direction, or in a direction that is generally away from where a user may access the bin interior. Directing airflow downward prevents air from blowing up towards a user/nearby people in use. Air exiting the bin may carry odours, so it is desirable to redirect the airflow away from people, and especially away from people’s faces. The operation of the fan may also produce a positive pressure inside the bin (forcing air out of the bin interior through the outlet(s)), making it harder for airborn pests, such as flies, to enter the bin.

The outlet may be formed between the lid and the bin (when the lid is attached/mounted to the bin), e g. a gap or opening formed between the periphery of the lid and the rim of the bin. Alternatively, the outlet may be, or comprise, an opening in the lid. The outlet may be formed at least partially by the lid.

The (inlet) fan may comprise an air inlet and outlet. The fan outlet may be in fluid communication with or coupled to the opening so as to direct air through the opening into the bin. The (inlet) fan may be disposed/positioned adjacent to or at least partially within the opening. The fan outlet may be positioned within, over or aligned to the opening. The fan may be integral with the lid or attached to the lid.

The lid may comprise a base portion and a cover portion. The base portion and the cover portion may define a cavity therebetween. The cavity may house the fan(s). The base portion of the lid may comprise the opening. The fan(s) may be disposed, positioned or mounted at least partially between the base portion and the cover portion. The fan(s) may be configured to generate a flow of air from outside the bin and lid into the interior bin through the cavity and the opening. The cover portion provides an enclosure that may help to prevent external elements from damaging the fan(s) or other components within the lid, for example due to water/material spillage onto the lid or rainfall if the bin is left outside. The cover portion may also provide acoustic insulation for the fan(s), reducing noise produced from the fan(s). The cover portion may also prevent people and/or animals from interfering with the operating of the fan and prevent people from seeing directly into the bin when the lid is closed, and also help prevent rodents/vermin from easily entering the bin. The cover portion may also make it easy to wipe-down the visible surfaces of the bin.

The lid may comprise an inlet for receiving a flow of air into the cavity from outside the lid and bin. The inlet may be formed between the cover portion and the base portion (e.g. a gap or opening between them). Alternatively, the inlet may be or comprise an opening in the cover portion.

The lid outlet may be formed between the base portion and the bin.

The base portion may be sized and configured to extend across the open/upper end of the bin, and/or support the lid on the bin. The base portion may comprise the engagement mechanism.

The base portion may comprise peripheral edge. At least a portion of the peripheral edge may be substantially curved or angled and configured to redirect a flow of air exiting the bin through the outlet. The curved peripheral edge may redirect the flow of air in a substantially downward direction. The curved peripheral edge may be curved in a downward direction. The curved peripheral edge may be positioned adjacent the outlet or form part of the outlet.

The curved peripheral edge may be curved below the horizontal. The curved peripheral edge may be curved between 30° and 90° below the horizontal. The curved peripheral edge may be curved between 45° and 90° below the horizontal. The curved peripheral edge may be curved between 60° and 90° below the horizontal. The curved peripheral edge may have an exit angle defined with respective to the plane of the base portion or the horizontal plane. The curved peripheral edge may have an exit angle of between substantially 30° and 90°, 45° and 90°, or 60° and 90° below the horizontal or base portion plane.

The fan(s) may be attached to the base portion. The fan(s) may be supported by the base portion.

The lid may comprise filtration means. The filtration means may be configured to remove odours and other potentially harmful components from air exiting the bin, e.g. though the outlet. The filtration means may comprise one or more filter units. The one or more filter units may be positioned adjacent or within an outlet of the lid through which a flow of air from inside the bin exits the bin. Additionally or alternatively, the one or more filter units may be positioned beneath the base portion. The filter units may comprise a filter material configured to absorb or trap odours, pollutants, volatile organic compounds and/or other chemicals or airborne particulates/microbes,. The filter units may comprise high-efficiency particulate air (HEP A) filters, an activated carbon filter, or any other filter with air purification particles.

The lid may incorporate other air purifying means to help neutralise odours, volatile organic compounds (VOCs) and airborne microbes, including UV and/or electric charge devices. The lid may comprise a UV light source to purify air and/or clean the bin interior via UV germicidal irradiation or photocatalytic oxidation. Alternatively or additionally, the lid may comprises an air ioniser device and/or a polarized-media filter.

The lid may comprise a filter or mesh extending across the opening and/or the exhaust outlet. The lid may comprise a filter or mesh extending across the opening in the base portion and/or the inlet. The filter or mesh may provide a physical barrier to inhibit the ingress of insect and airborne pests, such as flies. The filtration means may also provide a physical barrier to prevent pests or insect from entering the bin through the outlet.

The lid may be configured to form a seal (hermetic) against/around the upper/open end of the bin, e.g. by sealing against the rim of the bin when the lid is attached to or positioned on/over the upper/open end of the bin. The lid may comprise one or more sealing members attached to the underside of the base portion to seal against the rim of the bin in use. The sealing member(s) may extend at least partially around the peripheral edge of the base portion. This may ensure that air can only exit the bin by passing through the filtration means and may help trap odours contained within the bin.

The lid may comprise control means. The control means may comprise a switch. The switch may turn the fan(s) on and off. Alternatively or additionally, the control means may be configured to selectively operate the fan(s) based on one or more predetermined criteria. The predetermined criteria may include any one or more of: a change in weight of bin contents, temperature inside or outside the bin, humidity inside or outside the bin, time of day or predefined time interval, level of volatile organic compounds (VOCs) inside the bin, and whether the lid is open or closed, level of waste in the bin. The control means may comprise an internal clock or timer. The control means may be configured to operate the fan(s) and/or increase the fan speed continuously or periodically, and/or for a predetermined period of time, after the lid is closed.

The control means may comprise a sensing unit or sensing system. The sensing unit/system may be configured to determine one or more parameters of the bin. The parameters may be associated with the bin interior and/or the ambient conditions outside the bin. The sensing unit/system may comprise one or more sensors. The sensors may be located at any one or more of: on the underside of the lid, in the inlet, in the outlet, on the outside of the lid. The one or more parameters of the bin may comprise any one or more of: humidity, moisture, presence of volatile organic compound, temperature, time, lid position, weight of bin contents, and how full the bin is (i.e. fill level in the bin relative to the bottom or lid). One or more sensors may be positioned to measure parameters of the inlet air or the exhaust air. The control means may comprise a control unit. The control unit may be configured to control the fan(s) based on the one or more sensed parameters or sensor data received from the sensing unit. The control unit may be configured to selectively operate the fan(s) (on/off or fan speed) in response to a change in a sensed parameter. For example, the control unit may be configured to operate/active the fan(s) after the lid is closed continuously or periodically until a sensed parameter reaches/passes a threshold value.

Selectively operating the fan(s), rather than continuously operating the fan(s), reduces the power used by the fan. For example, once the contents of the bin are sufficiently dehydrated, there is no need for the fan(s) to be turned on. The level of dehydration may be defined by the water content. The level of dehydration may be monitored by the sensing unit (e.g. via a humidity sensor or the weight loss over time of waste put into the bin). Sufficient dehydration may be at least 30% weight reduction. Dehydration may be measured using a humidity sensor when the fan is inactive, by comparing a measured humidity value inside the bin to a predetermined value and/or a measured ambient air humidity. The power consumption of the lid is relatively low (e g. ~2 W for a single fan configuration), and with sensor control of the fan, this power consumption is reduced further. As a consequence the running cost of the device is low and it also facilitates the potential for self -powering.

The lid may comprise a power source. The power source may be disposed, positioned or mounted within the cavity between the cover and base portion. The power source may be configured to supply power to the fan(s) and the control means. The power source may be or comprise one or more photovoltaic cells, batteries, and/or thermoelectric generators. One or more photovoltaic cells may be mounted/incorporated to the lid or be a peripheral device electrically connectable to the lid allowing the photovoltaic cells to be located in sunlight. The thermoelectric generator may convert waste heat energy from external sources to electrical energy. For example, the thermoelectric generator may be connectable to a heat source, such as a fridge or freezer, an oven or a radiator.

Containing/mounting all working components in the lid of the bin enables the dehydration mechanism to easily work and be used with a variety of bin liner materials (e.g. paper liner, biodegradable starch liner etc.) or with no bin liners at all.

Alternatively or additionally, the lid may be connectable to mains power supply /electricity.

According to a second aspect of the invention there is provided a method for dehydrating contents of a waste bin having a lid. The method may comprise replacing air from inside the bin with ambient air from outside the bin (using one or more fans). The method may comprise replacing (moist) air from inside the bin with (relative fresh, less moist) ambient air from outside the bin.

Replacing air from inside the bin with air from outside the bin may comprise generating a flow of air from outside the bin into the interior of the bin. Generating an air flow may comprise using one or more fans provided on/or a lid of the bin. Replacing air from inside the bin with ambient air from outside the bin may comprise generating an inlet flow of ambient air from outside the bin and lid into the interior of the bin, and an exhaust flow of air from the interior of the bin to the surroundings, wherein the inlet flow and exhaust flow are generated using one or more fans.

The method may comprise filtering a flow of air exiting the bin to substantially remove odours, pollutants, VOCs, and/or other chemicals, compounds or microorganisms emanating from the food waste.

Generating a flow of air from outside the bin into the interior of the bin may comprise operating a fan or one or more fans provided on/or a lid of the bin. Generating a flow of air from outside the bin into the interior of the bin may comprise selectively operating the fan(s). Selectively operating the fan(s) may comprise operating or activating the fan periodically or continuously and/or for a predefined period of time after the lid is closed.

Selectively operating a fan may comprise sensing one or more of a humidity, volatile organic compound, temperature, time, position of the lid of the bin, fill level and/or weight of bin contents. The fan may be selectively operated in response to one or more sensed parameters exceeding or passing one or more predetermined threshold values.

According to a third aspect of the invention, there is provided a dehydrating bin comprising the lid of the first aspect. The bin may be a bin system comprising a bin with an open upper end, and a lid of the first aspect that is attachable to the upper end of the bin.

According to a fourth aspect, there is provided a device or dehydrator device for dehydrating contents of a bin. The device may be attachable or retrofittable to a lid of a bin or the bin itself to control the airflow within the bin. The device may comprise, when attached or retrofitted to a lid, any of the features of the first aspect. The device may comprise a fan, or one or more fans, configured to dehydrate contents of the bin, when fitted to the lid or bin. The device may be configured, using the fan(s), to generate a (inlet) flow of air from outside the bin (and lid) into the interior of the bin and a (exhaust) flow out of the bin to replace air inside the bin with air from outside the lid and bin and dehydrate the contents of the bin.

Features which are described in the context of separate aspects and embodiments of the invention may be used together and/or be interchangeable wherever possible. Similarly, where features are described in the context of a single embodiment for brevity, those features may also be provided separately or in any suitable sub-combination. Features described in connection with the lid of the first aspect may have corresponding features definable with respect to the method of the second aspect (and bin of the third aspect), and vice versa, and these embodiments are specifically envisaged.

Brief description of the drawings The invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows an exploded view of a lid for a bin;

Figure 2 shows a cross-sectional view of a lid for a bin;

Figure 3 shows a cross-sectional view of the airflow around a bin and lid for a bin;

Figure 4 shows a cross-sectional view of the airflow around the edge of the base of a bin lid;

Figure 5 shows a cross-sectional view of another lid for a bin;

Figure 6 shows a cross-sectional view of another lid for a bin;

Figure 7 shows example of different lids for a bin;

Figure 8 shows a perspective view of a sensing unit of a lid for bin;

Figure 9 shows an example of a control unit for a lid for a bin; and Figures 10 to 21 show different example configurations of lids.

Detailed description

Figure 1 shows an exploded view of a lid 10 for a bin 5 according to an embodiment of the invention. The lid 10 comprises a base portion 14, a fan 12, a cover portion 18 and a filtration means 20. The lid 10 is configured to dehydrate the contents of the bin 5 by replacing air from inside the bin, which may be substantially moist, with ambient air from outside the bin which is relatively dry.

The lid 10 is connectable to the upper or open end 5u of a bin 5. The lid 10 is sized according the dimensions of the bin 5 such that it covers the upper end 5u of the bin and engages the rim 5r of the bin.

The lid 10 can be retrofitted to a bin 5 (by replacing the original bin lid), or provided as part of a dehydrating bin system. In the example shown in Figure 1, the base portion 14 of the lid 10 is connectable to the bin 5 via a hinge mechanism 17. Hinge 17 enables a user to easily open and close the lid 10. The hinge 17 removably couples to a corresponding hinge member of the bin 5, allowing the lid 10 to be detached from, and reattached to, the bin 5.

The base portion 14 and the cover portion 18 define a space or cavity for housing the fan 12. The fan 12 is attached to or supported by the base portion 14 e.g. by one or more or fixings. The cover portion 18 is disposed above the base portion 14 and the fan 12. The cover portion 18 acts as a barrier to protect the fan 12 from external elements which may damage the fan 12, for example liquids or solids. The cover 18 prevents people from being able to access the fan 12 when the lid 10 is closed, for operator safety. The cover portion 18 also reduces audible noise from the fan 12 by acting as a baffle, and prevents people from being able to see the fan 12 when the lid 10 is closed.

The fan 12 is operable to replace moist air from inside the bin 5 with fresh ambient air from outside the bin 5. With reference to figure 2, the base portion 14 comprises an opening 19, and the fan 12 is arranged and configured to generate a flow of (ambient) air from outside the bin and lid through said opening 19 into the interior of the bin 5. In the example shown, the fan 12 is a centrifugal fan and the air outlet of the fan 12 is disposed within the opening 19 which can help secure the fan 12 in place, but it will be appreciated that this is not essential and it may instead be in fluid communication with the opening 19, e.g. via an intermediate conduit. In other examples, the fan 12 can be an axial fan (as shown in figure 7). In other examples, there are multiple fans 12 and multiple openings 19 within the base portion 14. For example, the fan 12 is an inlet fan 12 configured to generate an inlet flow of ambient air into the bin interior (as shown) and the lid can comprise an additional exhaust fan 12e to aid air extraction from the bin 5 (see figure 12).

The base portion 14 comprises a plurality of struts 16 that engage the rim 5r of the bin 5 and support the base portion 14 in an elevated position above the bin 5 to form an outlet 22 between the base 14 and the bin 5 through which a flow of air can exit the bin 5. In this example, the outlet 22 is a gap, created by the lid 10, which extends at least partially around the perimeter of the base portion 14. In other examples, the outlet 22 comprises an opening through the lid 10 (see figure 10).

Filtrations means 20 comprises a plurality of filter units configured to substantially remove unwanted odours, pollutants, and/or volatile organic compounds (VOCs) from the air flow exiting the bin 5 (see also figure 5). The filter units 20 are position adjacent or within the outlet 22 such that air exiting the bin 5 passes through the filter units 20. In an embodiment, the filter units comprise activated carbon, but it will be appreciated that any suitable filter material for absorbing odours, pollutants, and/or VOCs can be used. Although shown as a plurality of elongate elements, in other examples (not shown), the filtration means 20 may comprise a ring-like filter unit 20 that extends around the periphery of the base portion 14. The filter units are replaceable/exchangeable.

The base portion 14 may further comprise one or more sealing elements (not shown) to form a seal against the bin 5, ensuring that air can only exit the bin 5 by passing through the filtration means 20.

The base portion 14 and cover portion 18 are formed from thermo-formable mouldable plastic materials, e.g. via injection moulding. In one embodiment, the base portion 14 and cover portion 18 are formed from high-density polyethylene (HDPE). Other suitable materials include, but are not limited to: polycarbonate, acrylonitrile butadiene styrene, polyamide (nylon), acetal, polystyrene, and polyethylene. Recycled materials may also be used to make these components.

The cover 18 is positioned relative to the base 14 to provide an inlet 21 for receiving a flow of air from into the cavity from outside the lid 10 and bin 5. In the example shown in Figure 2, the inlet 21 is a gap formed between the cover portion 18 and base portion 14 which extends around the perimeter of the lid 10. The inlet 21 is configured to allow the fan 12 to convey air from outside the bin 5 into the lid 10 and through the opening 19. Additionally or alternatively, the inlet 21 comprises one or more openings in the cover portion 18 (not shown). In such examples, the fan 12 is configured to convey air from outside the bin 5 through said openings into the interior of the bin 5.

A filter or mesh can be provided within the opening 19 and/or inlet 21 and/or outlet 22 to provide a physical barrier inhibiting ingress of pests or insects, such as flies. The filtration means 20 may also help provide a physical barrier to prevent pests or insect from entering the bin through the outlet.

The cover portion 18 is connected to the base 14 and supported by via one or more support members 11 extending between the base portion 14 and the cover portion 18 (see figure 5). The support members 11 are configured to fix the cover 18 relative to the base 14 to maintain the gap for the inlet 21. In various embodiment, the cover 18 is removably coupled to the base portion, e.g. using screw or clip fixings, to provide access to the lid cavity and components such as the fan 12(s) and filter materials for maintenance and repair.

Figure 3 demonstrates the airflow within and around the bin 5. For clarity, the airflow is represented in three distinct sections, labelled using arrows A, B and C.

Airflow is generated by the fan 12. When activated, the fan 12 draws fresh ambient air situated outside of the bin 5 through the inlet 21 of the lid 10 into the cavity between the base 14 and the cover 18. This is represented using arrows A. Air within the cavity is then directed through the opening 19 into the inside of the bin 5. This is represented using arrows B.

The contents 6 (e.g. food waste) at the bottom of the bin 5 interact with air inside the bin 5 to produce moist air. Ordinarily, this accelerates decomposition and odour generation. The flow of air B into the bin 5 forces the moist air in the interior bin 5 to exit the bin 5 through an outlet 22 and encourages evaporation of water from the surface of moist materials/content within the bin. The flow out of the bins is represented using arrows C. In this way, the air flow generated by the fan 12 replaces the air content in the bin 5 with fresh air from outside. This air flow and circulation with ambient air maintains low moisture/humidity environment within the bin 5 and encourages evaporation, causing the contents 6 of the bin 5 to dehydrate which in turn reduces the rate of decomposition of the contents 6 and odour generation.

In the illustrated embodiment, the outlet 22 is configured to direct the flow exiting the bin 5 in a substantially downward direction to prevent the air that has passed through the bin 5 from travelling directly towards any persons in the vicinity. The process of redirecting the air through an outlet 22 is shown in greater detail in Figure 4. As shown, the base portion 14 comprises a curved peripheral edge 15 which interacts with air as it passes through the outlet 22. The arrows in Figure 4 are used to illustrate the airflow. The peripheral edge 15 is curved in a downward direction to redirect air through the outlet 22 and towards the ground. The peripheral edge 15 has an exit angle Q defined with respective to the plane of the base portion 14 or the horizontal plane, as shown. In the example shown, the peripheral edge 15 has an exit angle Q of substantially 80°-90°. In other embodiments, the peripheral edge 15 is angled.

Figure 5 shows a schematic cross-sectional view of an example lid 10 comprising filtration means 20 arranged and configured to remove odours from air exiting the bin 5 through the outlet 22 of the lid 10. The filtration means 20 comprises a plurality of filter units 20 disposed around the perimeter of the base portion 14 proximate the outlet 22. Support members 11 are spaced around the perimeter of the base portion 14. The support members 11 are configured to be sufficiently thin to avoid obstructing airflow through the inlet 21. The support members 11 may be integral with the cover portion 14 or base portion 14, or separate elements attachable to both the cover portion 14 and the base portion 14.

In embodiments where the lid 10 comprises two or more fans 12, one or more inlet fans 12 may be configured to convey fresh ambient air from outside the bin 5 (and lid) into the interior of the bin 5, whilst one or more outlet fans 12 are configured to convey moist air from inside the bin 5 to outside of the bin 5 (see figure 12). Where present, the outlet fan(s) are configured to direct the exhaust airflow through the filter material 20 prior to exiting the bin/lid.

Figure 6 shows a schematic cross-sectional view of an example lid 10 comprises a sensing unit 23 and a control unit 25. The sensing unit 23 is configured to determine or monitor one or more parameters of the bin 5, including one or more of: humidity, presence of VOCs, temperature, time, lid position (open or closed), fill level, and weight of bin contents 6. The control unit 25 is connected to the fan 12 and the sensing unit 23 and is configured to control the fan 12 based on one or more sensed parameters of the bin 5, including turning the fan on and off, and controlling the fan speed, The control unit 25 receives and processes data from the sensing unit 23 and controls the fan 12 based on one or more predetermined criteria or rules. In one example, the control unit 25 is configured to operate the fan 12 for a predefined period of time when it is determined that the lid 10 is closed. The fan 12 may be operated continuously or periodically to save power. In another example, in addition to or instead of timer control, the control unit 25 is configured to operate the fan 12 (continuously or periodically) until a sensed parameter such as humidity reaches a predefined threshold value. The threshold value may be indicative of the bin contents 6 being sufficiently dehydrated.

In the example shown, the control unit 25 is attached to an exterior wall of the bin 5 and the sensing unit 23 is attached to an underside (i.e. the side facing the interior of the bin 5) of the base portion 14 of the lid 10. In other examples, the control unit 25 and the sensing unit 23 may be positioned differently, e.g. the control unit 25 and the sensing unit 23 may be attached to the underside of the base portion 14, or one or both of the sensing unit 23 and the control unit 25 can be disposed within the cavity of the lid 10. Where the sensing unit 23 is disposed in the cavity, the base portion 14 may comprise an additional opening for the sensing unit 23 to measure interior bin parameters such as humidity and VOC. In another example, the control unit 25 and the sensing unit 23 may be integrated to form a single component. In some embodiment, the lid may comprise a memory to store measured and processed data, and wireless transceiver configured to transfer data to/from an external computing device such as a phone, tablet or server for remote monitor and/or analysis.

The control unit 25 may be connected to an external power source. For example, the control unit 25 may be connected via plug to the mains electrical supply. Alternatively, the sensing unit 23 and the control unit 25 may be connected to a power source which forms part of the lid 10. In one example, the lid 10 comprises one or more photovoltaic cells disposed on the cover 18. In other examples, the lid 10 comprises a battery. Where the lid 10 is battery powered, the battery may be rechargeable, and the lid 10 comprises a charging port for connecting to mains power.

In some examples, the power source may be contained within a docking station. The docking station may comprise a battery compartment and/or be connectable to mains electricity. The docking station may be configured to support the bin 5 and/or the lid 10 (e.g. the lid 10 may be detached from the bin 5 to connect to a docking station). The docking station may provide power to the control unit 25 and the sensing unit 23.

In other examples, the lid 10 may comprise a thermoelectric generator device which converts heat energy into electrical energy. The thermoelectric generator may be connectable to external appliances.

Figure 7 shows three more example lids 10. In these examples, none of the lids 10 have a cover 18, but all comprise a control unit 25 and a sensing unit 23.

Figures 7a and 7b show a lid 10 with two fans 12 disposed within the base 14. Figure 7c shows a lid 10 with a single fan 12 disposed within the base 14. The fans are connected to the base 14 by screws. The fans 12 are standard 5V fans. The fans may be centrifugal fans such as WINSINN 40mm 5V 4020 Blower fans. Alternatively, the fans may be axial fans, such as WINSINN 60mm 5V Brushless 6010 fans. Any other suitable type of fan may be used.

In Figure 7a, the sensing unit 23 is disposed on the interior of the bin 5. By contrast, in Figures 7b and 7c, the sensing unit 23 is disposed on an underside of the base 14.

Figure 8 shows an example where the sensing unit 23 is comprised of two distinct parts, 23a and 23b. The first part 23a is a magnet attached to the underside of the base portion 14. The second part 23b is comprises a reed switch. This sensing unit 23 is configured to detect whether the lid 10 is open or closed and send the information to a control unit 25.

In one example, the sensing unit 23 determines the temperature and humidity within the bin 5 and sends that information to the control unit 25. If the temperature and/or humidity within the bin passes or exceeds a predetermined threshold, the control unit 25 is configured to turn the fan 12 on and/or increases the fan speed. The sensing unit 23 may use a thermistor to determine the temperature inside the bin 5. The sensing unit 23 may comprise a humidity sensor, such as a TE Connectivity HPP801A031, Humidity Sensor or a DHT-11 or HCZ-H8-B Humidity Sensor.

In another example, the sensing unit 23 determines the levels of VOCs inside or outside the bin 5 and sends the information to the control unit 25. If a predetermined VOC level is exceeded, control unit 25 turns the fan 12 on and/or increases the fan speed. The VOC level may be detected using an SGP40 sensor, a BME680 sensor, or any other suitable type of sensor.

In another example, the sensing unit 23 determines the weight of the contents of the bin and sends the information to the control unit 25. If the weight of the contents of the bin exceeds a predetermined threshold, or there is a sudden increase in weight (indicating that new food waste has been placed in the bin 5), the control unit 25 turns the fan 12 on and/or increases the fan speed.

Dehydration can be monitored by tracking the change in humidity within the bin (using the humidity sensor) and/or by monitoring the reduction in weight of the bin contents over time. For example, in certain cases, weight reduction of 50% or more can be achieved and observed by flowing ambient air through the bin, associated with dehydration. Humidity values may reach 100% depending on the type of waste contents, and this can be reduced down to the ambient air humidity levels by flowing ambient air through the bin.

To determine the weight of contents in the bin 5, the sensing unit 23 may comprise a load cell optionally with a false floor/platform positioned at the bottom of the bin 5 or underneath the bin. It will be appreciated that any type of suitable weight measurement sensor can be implemented.

The sensing unit 23 may determine the amount of content in the bin using an internal fill monitor. For example, the fill monitor may be an ultrasonic sensor or an IR sensor.

In some examples, the control unit 25 comprises a timer. The sensing unit 23 detects when the lid 10 has been opened and closed and sends this information to the control unit 25. The control unit 25 turns the fan 12 on and/or increases the fan speed after a predetermined amount of time has passed since the lid 10 was opened and closed.

Additionally or alternatively to the magnet reed-switch described above, the sensing unit 23 may comprise a light-dependent resistor to enable the sensing unit 23 to detect whether the lid 10 is open or closed.

Figure 9 shows an example of a control unit 25 disposed in a base-plate platform. In this example, the control unit 25 is made using a Raspberry Pi zero W. The control unit 25 comprises a 5kg load cell and a HX711 analogue to digital converter. The control unit 25 may comprise a microcontroller, such as a ATTINY85-20PU, 8bit AYR microcontroller. The control unit 25 connects to the sensing unit 23 shown in Figure 8. The sensing unit 23 comprises a BME680 environmental sensor. BME680 is an all in one sensor that is configured to monitor humidity, temperature, and VOCs. The control unit 25 and the sensing unit 25 are connected using electrically conductive wires and a DuPont style connector. The wires are positioned along the back of the bin 5, as seen in Figure 9(c).

Figures 10-21 illustrate various embodiments and configurations for the lid 10, according to the invention.

Figure 10 shows a schematic diagram of a lid 10 without a cover, wherein an inlet fan 12 is attached to the lid to generate an inlet flow of air into the bin 5 through the opening 19. The fan 12 draws ambient air from outside the bin 5 and lid 10 and blows it onto the waste contained within, creating convection currents around it and hence promoting evaporation of liquids that may accumulate or be present on the surface of the waste or bin walls. The exhaust outlet 12 is provided by an opening in the lid 10 and connects the inside of the bin to the outside and provides a path for the moist air to exit the chamber. In this example, the lid 10 and bin rim 5r form a seal to inhibit/prevent air from escaping or leaking around the perimeter contact point. The lid 10 may be placed on the bin, or it may have a hinged opening. The opening 19 and outlet 22 may be positioned anywhere on the lid 10.

Figure 11 shows the lid 10 of figure 10 mounted on a bin 5 with a bin liner 6, demonstrating that the airflow dehydration mechanism continues to work with the use of a liner. In another variation, the bin liner may be freestanding within the bin base, i.e. not wrapped around the rim 5r (not shown).

Figure 12 shows a configuration of a lid 10 similar to that shown in figure 10 but with an outlet fan 12e positioned in or over the outlet 22 to promote moist air extraction from the bin 5. The outlet fan 12e is operated synchronously with the inlet fan, and at a speed corresponding to the inlet fan speed such that the exhaust flow substantially matches the inlet flow.

Figure 13 shows a configuration of a lid 10 comprising a filter unit 20 in the outlet 22 to help purify the exhaust air. In this example, the outlet is formed by a pipe or conduit 22c extending from an opening in the lid 10 and directing the airflow lateral to the bin 5. The filter unit 20 may be or comprise a particle filter, a chemical filter, and/or other suitable filtration means known the art. For example, a particle filter may be a pleated type, such as a HEPA filter. A chemical filter may help to remove odours, such as an activated carbon type. The filter unit may be replaceable. A sensor (not shown) may be positioned at or in the outlet 22 for monitoring one or more parameters of the exhaust flow, such as air quality after the filter. If the sensed parameter falls below a certain threshold, the control unit 25 (not shown) may generate a signal or alert prompting the user to replace the filter unit 20.

Figure 14 shows a variation of the configuration in figure 13 whereby the outlet 22 comprises a conduit 22c directing the airflow in a substantially downwards direction (any angle below the horizontal). In addition, the opening 19 is configured to direct the inlet airflow in an optimum direction for air circulation within the bin 5 and dehydration (any angle between vertical and horizontal).

Figure 15 shows a configuration of a lid 10 comprising an opening 19 and inlet fan 12 positioned substantially in the centre of the lid 10, and an outlet 22 formed between the lid and the bin rim 5r. In this example, the outlet 22 wraps around the rim of the bin 5r and directs the exhaust flow in a generally downwards direction (any angle below the horizontal).

Figure 16 shows a configuration of the lid 10 similar to that shown in figure 15 but including a cover 18 extending over the opening 19 and inlet fan 12. The cover 18 is suspended using struts 11 as shown in figure 5, but unlike figure 5 the cover 18 does not span the entire width of the lid 10. The cover 18 protects the fan 12 and any other electronic components from water/ material spillage onto the lid 10 or rainfall if the bin is located outside. The cover 18 can be sloped as shown to aid run-off of water. The cover also provides acoustic insulation and noise reduction from the fan 12, and prevents users and/or animals from interfering with the operating of the fan 12 (a filter of mesh can be provided across the inlet 21 and outlet 22 as described previously). It also helps to prevent rodents/vermin from easily entering the bin, and makes it easy to wipe-down the visible surfaces of the bin 5.

Figure 17 shows a variation of the lid 10 of figure 16 in which the cover 18 extends across the width of the lid 10 and the fan 12 is a centrifugal fan having an outlet coupled to the opening 19. As opposed to figures 1-3, the centrifugal fan 12 is mounted on its side (optionally at an angle to horizontal as shown) and opening 19 comprises an inlet conduit 19c to direct the inlet airflow into the bin 5.

Figure 18 shows a variation of the lid 10 of figure 17 comprising a side mounted centrifugal outlet/exhaust fan 12e. A filter unit 20 is also provided in the outlet conduit 22c.

Figure 19 shows the lid 10 of figure 18 with a plurality of sensors 23a-23e mounted at various locations around the lid 10 and bin 5 to monitor the one or more parameters of the bin (23a), inlet airflow (23b), outlet airflow (23c), surroundings (23d) and bin weight (23d).

Figure 20 shows an embodiment of the lid 10 in which the opening 19 and outlet comprises a nozzle 19n, 22n to increase airflow velocity. The inlet nozzle 19n is positioned downstream of the inlet fan 12. In this case, the opening 19 is a primary opening positioned downstream of the inlet fan 12, and the lid 10 further comprises a secondary opening 23 adjacent the primary opening 19 through which a secondary flow of ambient air from outside the bin 5 and lid 10 can enter the interior of the bin when the lid is attached to the bin. The secondary air flow is generated by the primary airflow exiting the nozzle 19n. The nozzle(s) 19n, 22n comprise or are shaped to form a Coanda surface 19s, 22s. The secondary inlet air flow is at least partially generated by the primary airflow over the Coanda surface 19s. This configuration increases the ambient airflow into the bin 5 for a given fan speed. A guide surface 19s 1 is located adjacent to the Coanda surface 19s, downstream of the nozzle 19n, to help direct/determine the direction of the airflow into the bin 5 so as to provide optimum circulation and evaporation. The Coanda surface 22s is positioned in a way that when the lid 10 is closed the airflow continues along the outer surface of the bin 5, in a downward direction - helping pull the air further downwards.

Figure 21 shows a variation of the lid in figure 20 comprising an exhaust fan 12e and a filter unit 20 provided between the exhaust fan 12e and the outlet nozzle 22n. The filter unit 20 may instead be positioned before the exhaust fan, in direct communication with the bin interior.

From reading the present disclosure, other variations and modifications will be apparent to the skilled person. Such variations and modifications may involve equivalent and other features which are already known in the art of ventilation and dehydration systems, and which may be used instead of, or in addition to, features already described herein.

Although the appended claims are directed to particular combinations of features, it should be understood that the scope of the disclosure of the present invention also includes any novel feature or any novel combination of features disclosed herein either explicitly or implicitly or any generalisation thereof, whether or not it relates to the same invention as presently claimed in any claim and whether or not it mitigates any or all of the same technical problems as does the present invention.

Features which are described in the context of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub combination. The applicant hereby gives notice that new claims may be formulated to such features and/or combinations of such features during the prosecution of the present application or of any further application derived therefrom.

For the sake of completeness, it is also stated that the term "comprising" does not exclude other elements or steps, the term "a" or "an" does not exclude a plurality, and any reference signs in the claims shall not be construed as limiting the scope of the claims.