Patent Application
20080006565
For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which:
The waste separation apparatus 1 uses a vortex to dislodge less dense waste from more dense waste, lift the less dense waste clear of the more dense waste and then throw the less dense waste clear of the more dense waste. The waste separation apparatus 1 is suitable to be used in any recycling process to separate different types of waste. The waste separation apparatus 1 is also suitable for use in, for example, the food industry to remove unwanted waste debris, such as discarded or uneaten food, from containers.
The waste separation apparatus 1 comprises a vortex initiator 10, a vortex generator 20, an endless conveyor 30 and an enclosure 40. The vortex generator 20 is arranged to direct the airflow generated by the vortex initiator 10 towards the endless conveyor 30 causing less dense waste to be thrown clear of the more dense waste.
In use, the endless conveyor 30 is arranged to extend at first and second ends 31, 32 beyond the enclosure 40 and the vortex generator 20 is arranged within the enclosure 40. Waste to be separated is located at the first end of the conveyor and is transmitted into the enclosure where it is acted upon by the generated vortex. The less dense waste is thrown clear of the endless conveyor 30, and the more dense waste is advanced out of the enclosure for further processing. Less dense waste receivers are positionable beneath the endless conveyor 30 to collect the less dense waste thrown clear of the conveyor 30 to be processed itself. The waste separation apparatus 1 can be used as a stage in a process line to recycle and/or clean waste.
Less dense waste is waste that has a density of less than or equal to a predetermined density. The apparatus 1 is adaptable to vary the predetermined density of the less dense waste lifted and thrown clear by altering the distance between the generator 20 and the conveyor 30. The predetermined density can be set to, for example, separate plastic bottles from glass bottles; light plastics, such as bags and wrappers, from heavy plastics, such as food containers and bottles; plastics from metal cans; and other waste to be separated.
The vortex initiator 10 is located externally to the enclosure 40 and comprises an air inlet 11, a supply fan 12, and an air outlet 13. The provision of the vortex initiator externally to the enclosure improves its maintainability as access to, for example, the supply fan is improved.
The air inlet 11 allows air in the enclosure to be communicated to the air outlet 13 by the supply fan 12.
As an alternative, the air inlet 11 could be such as to allow air from outside the enclosure to be communicated to the air outlet 13 by the supply fan 12. The air outlet 13 allows air from the supply fan 12 to be communicated to the vortex generator to separate waste on the conveyor 30.
The supply fan 12 is configured to increase the velocity of the air flowing in from the air inlet 11 and communicate that air with increased velocity to the air outlet 13. The velocity of the air is controlled so that the strength of the vortex generated lifts waste of up to a predetermined density from the conveyor 30 and throws it clear of the conveyor 30 for further processing rather than suck it into the vortex generator 20. The initiator 10 is configured to operate to transmit air of a predetermined velocity to the generator 20. The predetermined velocity can be controlled to facilitate separating waste of up to a predetermined density from more dense waste. The higher the predetermined velocity the greater the predetermined density of waste that is lifted from the conveyor 30.
The vortex generator comprises a duct 21 and a drum 22. The duct 21 is connected to the air outlet 13 to communicate air from the vortex initiator 10 into the drum 22. The duct comprises an entry 21a into the drum 22 through which the airflow from the initiator 10 is directed.
The drum 22 comprises a cylindrically-shaped or cone-shaped chamber 23 with a closed end 24 and an opposed open end 25. The drum 22 is configured to direct air received from the vortex initiator 10 towards the conveyor 30.
The air introduced into the vortex generator 20 from the vortex initiator 10 exits the generator 20 at the open end 25. The generator 20 is positioned to communicate air from the closed end 24 to the open end 25 to the conveyor 30 to disturb and dislodge the less dense waste. In the preferred embodiment, the duct 21 is positioned to introduce air into the closed end 23 and the open end 24 is positioned above the conveyor 30.
The shape of the drum 22 causes the air flowing within it to form the vortex. The shape of the drum 22 causes the air from the initiator 10 to rotate about the inner wall 26 of the drum 22. The rotation causes a vortex to be formed, i.e. high velocity air communicated to the drum 22 from the initiator 10 is forced to rotate about the inner wall 26 causing the formation of a high pressure region relative to the inner wall 26 and a lower pressure region relative to the centre 26 of the drum 22 about which the high velocity air and high pressure region rotate. The effect of the high pressure region and low pressure region is to generate an area of negative pressure in the drum 22.
In use, the waste entering the enclosure 40 is increasingly moved along the conveyor 30 so that the waste is first engaged with the high velocity air, which disturbs the waste. The less dense waste is then lifted clear from the conveyor due to the effect of the negative pressure area generated towards the centre of the vortex. The less dense waste is then thrown clear of the conveyor 30 and deposited at the base of the enclosure 40. The distance between the conveyor 30 and the open end 25 can be varied to alter the predetermined density of the less dense waste that is lifted and thrown clear of the conveyor 30.
The enclosure 40 comprises a first and second opening 41, 42 through which the first and second ends 31, 32 of the conveyor 30 extend. Waste is introduced into the enclosure 40 through the first opening 41 in a plurality of containers 35. Within the enclosure the less dense waste is separated from each of the containers 35 leaving the more dense waste in each of the containers 35. The containers exit the enclosure 40 through the second opening 42.
The less dense waste is thrown clear of the conveyor 30 and other containers on the conveyor 30 by the vortex. The less dense waste is collected in a separator collection area 45 at the base of the enclosure 40. The efficiency, in terms of waste throughput, is limited by the separation efficiency between the containers 35.
The effect of the vortex is to lift and throw the less dense waste clear of the conveyor. The further the less dense waste moves from the conveyor the less the vortex has an effect on the less dense waste causing it to be deposited in the separator collection area 45. The deposition of the less dense waste in the collection area 45 means that the need for additional air filtration equipment is dispensed with. The separator collection area 45 can comprise an additional endless conveyor, auger, blow line and/or bins to facilitate removal of the less dense waste from the enclosure 40.
The endless conveyor 30 further comprises side walls fitted to the conveyor to prevent the waste from being inadvertently removed from the conveyor 30 by the vortex. In the instance where the waste is not deposited directly onto the conveyor 30 but is contained within a container or series of containers 35, the conveyor 30 will comprise additionally of side guides to releasably fix the container 35 to the conveyor 30. The endless conveyor can further comprise top guides to releasably fix a container 35 to the conveyor 30. The guides are provided to prevent the vortex affecting the alignment of the container on the conveyor 30.
The waste separation apparatus 1 is fabricated from stainless steel, protected mild steel, aluminium or other suitable materials. The apparatus 1 is fabricated from stainless steel for use in the food industry. The apparatus is fabricated by casting, extrusion, pressing or other suitable fabrication processes.
In the preferred embodiment, the duct 21 extends tangentially from the drum adjacent to the closed end 24 in an elongated arc with respect to the circumference of the inner wall 26. The elongated arc causes the airflow to be directed against the inner wall 26, and, as the chamber 23 is cylindrical or cone shaped, the airflow is directed to rotate about the inner wall causing a vortex to be formed.
The debris director 50 has an opening 51 into the open end 25 of the drum 22 arranged to correspond with the negative pressure area and a duct 52 to transmit the debris from the debris director 50 to the collection area 45. The director 50 causes debris or less dense waste to be lifted from the conveyor through the opening 51 and into the duct 52. The debris director is arranged to substantially prevent the high pressure region of the vortex from affecting the waste on the conveyor 30. This arrangement ensures that unwanted waste separation does not occur through the vortex picking up waste comprising the incorrect density.
Although the duct 52 is described as being arranged within the enclosure 40, the duct 52 and enclosure 40 can easily be adapted to allow the duct 52 to extend beyond the enclosure 40 to deposit the separated waste externally for further processing.
The air inlet 61 is located centrally on the closed end 24 of the drum 22 to correspond with the centre of the low pressure region of the vortex formed in the drum 22. The air inlet 61 is arranged to communicate air from the drum 22 to the suction fan 62. The suction fan 62 sucks air from the drum and expels that air through the air outlet 62. In the preferred embodiment, the suction fan 62 is positioned externally to the enclosure for ease of maintenance.
The speed of the suction fan 62 is controlled to control the density of waste separated from the conveyor 30. The speed of the suction fan determines the amount of air extracted from the drum. The air inlet 61 is located centrally above the drum to correspond with the low pressure region formed by the vortex. The air sucked from the drum 22 through the air inlet 61 further reduces the pressure in the low pressure region. The reduction in pressure leads to the difference in pressure between the high pressure region and low pressure region being increased, resulting in an increase in the negative pressure between these regions.
The vibration means 301 comprises a vibration motor configured to vibrate a conveyor section 305 of the vibrating conveyor 300. The vibration means 301 causes the conveyor 300 to vibrate in both horizontal and vertical planes relative to the first and second ends 31, 32 of the conveyor. The vibration causes the advancement and promotion of waste as described above. The vibration means 301 further comprises a plate 303 connected to the conveyor section 305 by at least one arm 304. The arms and plate are provided to resiliently support the conveyor section 300.
The conveyor section 305 further comprises sidewalls 302 to prevent the waste from being inadvertently removed from the vibrating conveyor 300 by the vortex. The sidewalls 302 are provided to prevent waste with a density greater than the predetermined density from being removed from the vibrating conveyor 302. The conveyor section 305 is shaped to be a trough with a U-shaped cross section.
Although the features of the second, third and fourth embodiments have been described as functioning in isolation of each other, the person skilled in the art would appreciate that the features of these embodiment may be easily combined. For example, to boost targeted separation, the vibrating conveyor 300 can be easily combined with the vortex suction fan apparatus 60. Such a combination provides an apparatus where the less dense waste is more easily separated from the more dense waste, and the strength of the vortex can be accurately controlled to ensure that only waste of the predetermined density is thrown clear of the conveyor 300.
The waste separation apparatus 1, 2, 3, 4 according to embodiments of the present invention is easily maintainable and efficient. The apparatus 1, 2, 3, 4 comprise a small number of moving parts, which are easily accessible for maintenance or repair. The efficiency of the apparatus is only limited by the amount waste that can be provided on the conveyor 30, 300.
Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.
All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.
Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.
The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 0613351.6 | Jul 2006 | GB | national |
