WO2014059478A1

WO2014059478A1 - Organic waste treatment system

Info

Publication number: WO2014059478A1
Application number: PCT/AU2013/001200
Authority: WO
Inventors: Noel Mancuso
Original assignee: Pioneer Waste Management Holdings Pty Limited
Priority date: 2012-10-16
Filing date: 2013-10-16
Publication date: 2014-04-24
Also published as: AU2016256670A1; AU2016102395A4; AU2013205579A1

Abstract

Described herein is a mobile organic waste treatment system. The system includes a vehicle which carries a power supply, a hopper for receiving organic waste from an organic waste receptacle, a comminution unit for receiving the organic waste from the hopper and reducing the volume of the organic waste by comminuting the organic waste with water from a water reservoir to form a liquid slurry, the comminution unit being connected to and supplied with power from the power supply, a holding tank in fluid communication with the comminution unit to receive the liquid slurry therefrom, a washing assembly for washing the organic waste receptacle with water from the water reservoir, and a feeding means for feeding the organic waste from the hopper to an inlet of the comminution unit in a controlled manner.

Description

Organic waste treatment system

Field of the invention

The present invention relates to an organic waste treatment system, and in particular to a mobile organic waste treatment system. Background of the invention

Organic waste is generated in a wide variety of environments including anywhere food is prepared and/or consumed. Such waste includes organic material that is not used in food preparation, is prepared for consumption but left over/not consumed, or has spoiled is otherwise unwanted. This organic material may include, for example, fruits, vegetables, grains, nuts, seeds, breads, dairy products, meats, oils, juices, and bones.

The manner in which organic waste is disposed of can have financial and environmental ramifications. For example, organic waste disposed of by traditional garbage collection services typically results in the organic waste ending up in landfill.

Financially, landfill disposal such as this can be expensive. Organic waste can be bulky/heavy, and tipping fees are ever increasing. For example, the approximate landfill costs in Australia were $160 per ton in 2010, $225 per ton in 2011, and $280 per ton in 2012.

In addition, landfill disposal may be considered environmentally or socially undesirable.

In order to provide an alternative means of disposing of organic waste, organic waste treatment systems which comminute raw organic waste are known. While these organic waste treatment systems can be appropriate for installation in environments which produce a relatively large amount of organic waste, they may not be appropriate of desirable for environments which do not produce such large quantities of waste, do not have the space to install the waste treatment system and holding tank, or are unable to install the system/holding tank for other reasons (e.g. lease or planning restrictions).

For environments where it is impossible or impractical to install an organic waste treatment system (or for entities which simply do not wish to do so), it would be desirable to provide an alternative option for organic waste disposal. Reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that this prior art forms part of the common general knowledge in Australia or any other jurisdiction or that this prior art could reasonably be expected to be ascertained, understood and regarded as relevant by a person skilled in the art. Summary of the invention

In one aspect the present invention provides a mobile organic waste treatment system including: a vehicle carrying: a power supply; a hopper for receiving organic waste from an organic waste receptacle; a comminution unit for receiving the organic waste from the hopper and reducing the volume of the organic waste by comminuting the organic waste with water from a water reservoir to form a liquid slurry, the comminution unit being connected to and supplied with power from the power supply; a holding tank in fluid communication with the comminution unit to receive the liquid slurry therefrom; a washing assembly for washing the organic waste receptacle with water from the water reservoir; and a feeding means for feeding the organic waste from the hopper to an inlet of the comminution unit in a controlled manner. The vehicle may also carry a lifting assembly for lifting the organic waste receptacle into a tipping position in which the organic waste is tipped into the hopper.

Operation of the feeding means may be automatically commenced when an organic waste receptacle is lifted into the tipping position by the lifting assembly. Operation of the feeding means may be automatically terminated on completion of an operational cycle of the comminution unit or after a predetermined period of time.

The feeding means may be a screw auger or a conveyor extending from an outlet of the hopper to the inlet of the comminution unit.

The water reservoir may be carried by the vehicle and is in fluid communication with the comminution unit and the washing assembly. The vehicle may further carry a main pump assembly for pumping water from the water reservoir to one or more of the comminution unit and the washing assembly.

The washing assembly may include a heater for heating water from the water reservoir. The washing assembly may include a lance fitted at one end with a spray assembly for spraying water into the organic waste receptacle, the lance being connected to the water reservoir. The lance may be mounted via a lance actuator, the lance actuator being configured to move the lance between an extended position in which the lance extends into the organic waste receptacle and a retracted position in which the lance is retracted out of, or substantially out of, the organic waste receptacle. The washing assembly may include a washing assembly pump for pumping water from the water reservoir to the lance. When the organic waste receptacle is lifted into the tipping position the actuator may be automatically operated to move the lance to the extended position and/or the washing assembly pump may be automatically operated to spray water out of the spray assembly and into the organic waste receptacle.

Also described herein is a mobile organic waste treatment system including: a vehicle carrying: a power supply; a comminution unit for receiving organic waste from an organic waste receptacle and reducing the volume of the organic waste by comminuting the organic waste with water from a water reservoir to form a liquid slurry, the comminution unit being connected to and supplied with power from the power supply; a holding tank in fluid communication with the comminution unit to receive the liquid slurry therefrom; and a washing assembly for washing the organic waste receptacle with water from the water reservoir.

The water reservoir may be carried by the vehicle and in fluid communication with the comminution unit and the washing assembly. The system may further include a pump assembly for pumping water from the water reservoir to the comminution unit and/or the washing assembly.

The system may further include a lifting assembly for lifting the organic waste receptacle.

The lifting assembly may be configured to lift the organic waste receptacle and deposit the organic waste from the organic waste receptacle into an inlet of the comminution unit. Alternatively, the lifting assembly may be configured to lift the organic waste receptacle and deposit the organic waste from the organic waste receptacle into a hopper.

The waste treatment system may further include a feeding means for controlled feeding of organic waste from the hopper to an inlet of the comminution unit. The feeding means may be a screw auger or a conveyor.

The lifting assembly may be connected to and powered by the power supply.

Further aspects of the present invention and further embodiments of the aspects described in the preceding paragraphs will become apparent from the following description, given by way of example and with reference to the accompanying drawings.

Brief description of the drawings

Figure 1 is a schematic diagram of a mobile organic waste treatment system in accordance with an embodiment of the invention.

Figure 2A is a schematic partial rear elevation view of the mobile organic waste treatment system of Figure 1. In Figure 2A a lifting assembly is depicted in a collection position and a washing lance is depicted in a retracted position.

Figure 2B is a similar view to Figure 2A. In Figure 2B the lifting assembly is depicted in a tipping position the washing lance is depicted in a retracted position.

Figure 2C is a similar view to Figure 2A. In Figure 2C the lifting assembly is depicted in a tipping position the washing lance is depicted in an extended position.

Figure 3 is a sectional depiction of a comminution unit suitable for use with the present invention.

Figure 4A provides a partial cross-sectional elevation view of a processing unit suitable for use with the comminution unit of Figure 3. Figure 4B provides, an alternative partial cross-sectional elevation view of the processing unit of Figure 4A, the section of Figure 4B being at 90° to the section shown in Figure 4A.

Figure 4C provides a partial perspective view of the processing unit shown in Figures 4A and 4B.

Figure 4D provides a schematic top view of the pre-processing means of the processing unit of Figures 4A to 4C. Figure 4E is a partial perspective view of a processing unit with the pre-processing means removed.

Figure 5A is a schematic sectional view of a pump assembly for use with the comminution unit of Figure 3.

Figure 5B is a perspective view of the pump suction chamber of the pump assembly of Figure 5A.

Figure 5C is a front view of the pump suction chamber of Figure 5B.

Figure 5D is a top view of the pump suction chamber of Figure 5B.

Figure 5E is a left elevation view of the pump suction chamber of Figure 5B.

Figure 5F is a sectional view of the pump suction chamber taken along section A— A of Figure 5E.

Figure 6 is a control schematic of the comminution unit of Figures 3 to 5.

Figure 7 is a schematic of the plumbing of the comminution unit of Figures 3 to 5.

Figure 8 is a schematic diagram of a washing assembly for use with the mobile organic waste treatment system of Figure 1.

Figure 9A is a perspective diagram of a holding tank 110.

Figure 9B is an enlarged partial perspective view of one foot of the holding tank 110.

Figure 1 OA provides a flow chart depicting the operation of the waste processing system during an automatic processing cycle.

Figure 10B provides a flow chart depicting the operation of the waste processing system during a liquid processing cycle.

Figure IOC provides a flow chart depicting the operation of the waste processing system during a wash cycle. Figure 10D provides a flow chart depicting the operation of the waste processing system on activation of an emergency stop control.

Figure 11 provides a schematic of an organic waste collection hopper and feeding means for use with one embodiment of the invention. Figure 12 is a schematic diagram of a mobile organic waste treatment system in accordance with a further embodiment of the invention.

Detailed description of the embodiments

Referring to Figure 1, a broad overview of a mobile organic waste treatment system 100 in accordance with an embodiment of the invention will first be provided. Following this overview various sub-components and features of the system will be described in further detail.

Overview

The mobile organic waste treatment system 100 of the present embodiment is a vehicle 102 which carries a variety of components. At a high level these components include a lifting assembly 104, a comminution unit 106, a washing assembly 108, a holding tank 1 10, a water reservoir 1 12, and a power supply 114. These components are secured to the vehicle 102, for example by being bolted to the chassis, sub-frame, and/or tray of the vehicle 102.

In operation, the vehicle 102 is driven/transported to a site from which organic waste is to be collected. This may be any site which produces organic waste, for example houses, units, apartment blocks, restaurants, cafes, fast-food outlets, food courts, function centers, demonstration kitchens, training kitchens, school/university cafeterias, fruit and vegetable (or other food) vendors, supermarkets, hospitals, clubs, bakeries, markets, show-grounds, etc.

At the relevant site, the organic waste will have been initially disposed of into a dedicated on-site organic waste receptacle 116. In one embodiment of the invention typical wheelie bins will be used for this purpose, such as those supplied by Harris Hygiene & Handling (for example their 80L, 120L, and 240L wheelie bins - the size for a particular site being selected according to the site needs). For example: relatively smaller bins - such as 80L bins - may be appropriate for sites which produce waste having a relatively high weight to volume ratio (e.g. cafes and coffee shops where much of the waste is densely packed coffee grounds); medium size bins - such as 120L bins - may be appropriate for sites which produce waste having an average weight to volume ratio (e.g. fruit shops and the like); and relatively larger bins - such as 240L bins - may be appropriate for sites which produce waste having a relatively low weight to volume ratio (e.g. bakeries and the like where much of the waste bread). Any other type or size of receptacle may, of course, be used.

In order to simplify the initial disposal of the waste at the site (e.g. from the kitchen to the receptacle 1 16), and reduce the likelihood of non-organic waste being deposited into the organic waste receptacle 116, the receptacle 116 may be distinguished by being a particular colour - such as purple - to allow staff/personnel to easily distinguish the organic waste receptacle 116 it from other waste bins that may be used on the site.

As shown in Figure 2 A the organic waste receptacle 116 is positioned appropriately for engagement with the lifting assembly 104. The lifting assembly 104 then lifts the receptacle 116 into a tipping position to empty the organic waste out of the receptacle 116. In one embodiment the organic waste is emptied directly into the comminution unit 106 (as shown in Figure 2B). In an alternative embodiment the organic waste is emptied into a hopper and fed from the hopper 1102 to the comminution unit 106 in a controlled manner (as per Figure 11).

While the organic waste receptacle is in the tipping position the washing assembly 108 is operated to direct water into the organic waste receptacle 116. This assists in dislodging organic waste that may be stuck in the receptacle 1 16 (i.e. that has not simply fallen into the comminution unit 104 due to gravity) and to wash the interior of the receptacle 116. The water supplied in the washing process also ends up in the comminution unit 106 and assists in the comminution process. Water for the washing assembly 108 is supplied from the water reservoir 112 via a pipe or hose 1 18.

Once the organic waste has been emptied into the comminution unit 106, the comminution unit 106 is operated to reduce the volume of the waste and create a flowable liquid slurry by comminuting the organic waste with water. The water is pumped from the water reservoir 1 12 to the comminution unit 106 by pump 120 through pipe or hose 122. The liquid slurry is then pumped to the holding tank 110 (by a pump which is in this instance a subcomponent of the comminution unit 106) via pipe or hose 124. The volume reduction achieved by the comminution process depends, of course, on the type of organic waste being processed. By way of example, however, tests have shown that on average: organic waste from bakeries (being predominantly bread) reduces in volume by around 50%; organic waste from fruit and vegetable vendors reduces in volume by around 40%; and organic waste from cafes/coffee shops (including large volumes of densely packed coffee grounds) reduces in volume by around 15%.

Once the receptacle 116 has been emptied of organic waste and washed, the lifting assembly 104 lowers the receptacle 1 16 back to the ground.

The various components of the mobile waste treatment system are powered by power supply 114 (though for clarity power connections have not been depicted in Figure 1 ).

The vehicle can then be driven/transported to a new site (provided the holding tank 110 has capacity for additional waste collection operations), or back to a base/final disposal location where the liquid slurry is emptied from the holding tank 1 10.

The liquid slurry produced by the comminution unit 106 and stored in the holding tank 110 is, in itself, a useful and valuable waste stream. The slurry can be used, for example, as a rich feed source for biodigestors - anaerobic reactors where the slurry is used to produce 'biogas' which can be used as a fuel source to generate electricity. This technology has been implemented, for example, by Biotechnische Abfallverwertung GmbH Co KG (BTA). Alternatively, the slurry can be used for composting or soil injection. Still further, the liquid slurry can be de-watered and the resulting solid matter used as an organic fertilizer.

Various components and features of the mobile waste treatment system 100 will now be described in detail.

Vehicle

Vehicle 102 will typically be a motor vehicle such as a truck with sufficient carrying capacity (both in terms of area and power) to carry the required components.

As discussed below, in one particular embodiment the capacity of the holding tank 110 is 5,000 litres. For a holding tank of this size, a 500L to 1000L water reservoir 112 is likely to be appropriate. In this embodiment suitable motor vehicles 102 include (though are not, of course* limited to) the Isuzu F-series trucks such as the FRR 500 and FRD 500.

It will be appreciated that in alternative embodiments the holding tank 110 may have greater or lesser capacity, and in order to supply sufficient water for processing operations to fill the holding tank 110 the water reservoir 112 may also have a greater/lesser capacity (the capacity of the water reservoir being determined according to the capacity of the holding tank). Depending on the capacities of the holding tank 1 10 and water reservoir 112, and their weight when full, and a larger or smaller truck may be appropriate.

It will also be appreciated that vehicle 102 could be a non-powered vehicle, such as a trailer, adapted to be towed by a motor vehicle (e.g. a truck/car/utility etc).

Vehicle 102 will include a chassis (not shown) to which a sub-frame 902 (and, in some instances, a flat bed 126) are secured. The various components of the system are, in turn, secured to and supported by the chassis, flatbed 126 and/or sub-frame 902.

Lifting assembly The particular lifting assembly 104 used will depend on the type of waste receptacles 116 being used at the various collection sites.

As discussed above, in a particular embodiment the on-site organic waste receptacles will be 80/120/240 Litre wheelie bins such as those manufactured by Harris Hygiene and Handling. In this case a lifting assembly such as the Multi-tip® unit manufactured/supplied by Harris Hygiene and Handling will be appropriate, and is connected to and powered by the power supply 114.

Alternative lifting assemblies, for example hydraulic, electric, pneumatic, or manually operated lifters are, of course, possible

Figures 2 A and 2B provide schematic partial rear elevation views of the vehicle 102 in which depictions of one possible type of lifting assembly 104 and comminution unit 106 (in section) can be seen. In Figure 2A the lifting assembly 104 is depicted in a collection position and in Figure 2B the lifting assembly 104 is shown in a tipping position. The lifting assembly 104 includes a receptacle engagement means 202 adapted to engage with the receptacle 1 16. Engagement means 202 may, for example, be a claw or clasp type means for gripping around the body of the receptacle 116, a hook type means for engaging with a rim of the receptacle 116, a platform type means for supporting the base of the receptacle, or a combination of different types of engagement means.

The receptacle engagement means 202 is pivotally connected to a lifting arm 204 by a first pivot 206. The lifting arm 204 is, in turn, pivotally connected to a lifting mechanism 208 by a second pivot 210.

In operation, the engagement means 202 engages with the receptacle 116 (as shown in Figure 2A), and the lifting mechanism 208 is operated to raise the lifting arm 204 to lift the receptacle 116 into a tipping position as shown in Figure 2B. In the tipping position the lid 212 of the receptacle 116 is swung out of the way, and the mouth of the receptacle 1 16 is pressed against a seal 214 provided at the mouth of the comminution unit 106 in order to reduce or prevent contents of the receptacle from escaping the comminution unit 106. At completion of the collection process the receptacle 116 is lowered back to the collection position, and the engagement means disengaged from the receptacle 116.

For convenience, lifting assembly 104 is mounted to the vehicle 102 so as to engage with and lift on-site receptacles 116 at the curb side of the vehicle 102. The lifting assembly 104 could alternatively be positioned at the rear of the vehicle or the non-curb side of the vehicle. In some embodiments the lifting assembly 104 will have a dedicated control unit including one or more controls for raising a receptacle 116 into the tipping position and lowering the receptacle 1 16 back to the ground. In alternative embodiments the lifting assembly 104 may be connected to a central controller (e.g. the comminution unit controller 306 as discussed below) and controlled from that controller. While having the lifting assembly carried by the vehicle 102 is convenient (and means that each collection site does not need to provide or be provided with their own lifting equipment), in some embodiments the lifting assembly may not be carried by the vehicle. In these embodiments the on-site organic waste receptacles are emptied into the comminution unit 106 carried by the vehicle 102 by on-site lifting equipment. Comminution unit

Comminution unit 106 operates to comminute the organic waste for example by grinding and/or shredding. It will be appreciated that a variety of comminution units would be suitable for this process. Turning to Figures 3 to 6, a suitable comminution unit 106 will be described by way of non limiting example.

Figure 3 is a sectional depiction showing the high-level components of comminution unit ^• 106. The comminution unit 106 includes a waste processing unit 302, a pump assembly 304, and a control unit 306. The various components of the comminution unit 106 are housed in a housing which is provided with an opening for a main water inlet pipe 308 (connected via plumbing to the water reservoir 112) and a slurry outlet pipe 310 (for delivering the liquid slurry to the holding tank 110). Additional openings and connections are also provided, for example in order to connect the comminution unit 106 (and the various powered components therein) to the power supply 114. In order to facilitate emptying of the contents of the receptacle 1 16 when the receptacle is in the tipping position, a bin receiving means is provided. In the embodiment depicted in Figures 2 A to 3 and 11, the bin receiving means is an angled hood 312. The hood 312 includes an angled face 314 (in this case approximately 45 degrees) with an opening 316 therein, and feeds into the funnel assembly 402 of the processing unit 302. A rubber seal 318 is provided around the opening 316.

In alternative embodiments the bin receiving means may be a chute with a mouth sufficiently wide to receive the mouth of the receptacle 116 therein when in the tipping position (i.e. sized so that when in the tipping position the mouth of the receptacle 116 is positioned inside the chute and below the top of the chute, the chute thereby catching all organic material from the receptacle 116 and preventing it from escaping).

In the embodiment of Figures 2 A to 3 the bin receiving means is secured to the top of the comminution unit 106. In an alternative embodiment, described below with reference to Figure 1 1, the top of the comminution unit is sealed by a lid and organic waste is introduced into the comminution unit 106 from a hopper 1102 in a controlled manner by a feeding means.

Opposite the opening 316, the bin receiving means (whether a hood, chute, or alternative means) also includes an aperture fitted with a wiper seal 320 through which an extendable water lance 322 (described further in relation to the washing assembly 108) extends.

In use, when the bin receiving means is a hood, when a receptacle 116 is in the tipping position the mouth of the receptacle aligns with the opening 316, and the rubber seal 318 seals against the receptacle to prevent spillage. The contents of the receptacle 116 are tipped into the funnel 402 of the processing unit 302 for processing. When the bin receiving means is a chute, the mouth of the receptacle 116 is positioned inside the chute which directs the organic waste into the funnel of the processing unit. In both cases water lance 322 is extended into the receptacle 1 16 (as depicted in Figure 2C) to assist in washing the organic waste in the receptacle into the processing unit 302. Processing unit

The processing unit will be described with reference to Figures 4A to 4E.

Starting at Figures 4A and 4B, processing unit 302 includes a funnel assembly 402 for receiving the organic waste material to be processed, and which tapers generally inwardly from its mouth to its base. In this instance the funnel assembly 402 includes: an upper segment 403, a middle segment 404, and a lower segment 405.

The upper funnel segment 403 is a stepped funnel having (from top to bottom) an outwardly extending upper annular flange 406, an upper wall section 407 extending downwardly from the flange 406 and angled inwardly, a middle step section 408 extending inwardly from the bottom of the upper wall section 407 at an approximately horizontal angle, a middle wall section 409 extending downwardly from the inner edge of the step 408 and angled inwardly, and a lower wall section 410 extending approximately vertically downward from the middle wall 409.

The middle segment 404 of the funnel assembly is roughly cylindrical and at its top fits around/receives the lower wall section 410 of the upper funnel segment 403 at its top. The length of the middle segment 404 of the funnel assembly 402 can be selected so as to alter the capacity of the funnel assembly 402 (i.e. the amount of waste that can be held in the funnel assembly and processed by the unit in a single operational cycle). A longer middle segment 404 will provide a processing unit with a higher capacity than a shorter middle section.

The lower segment 405 includes a substantially vertical wall 411 (which fits around/receives the middle segment 404), a middle wall 412 (extending downwardly and inwardly from vertical wall section 411), and an outwardly (and approximately horizontally) extending lower flange 413 at its base.

The upper middle and lower funnel assembly segment 403, 404, and 405 are, in the present embodiment, separate unitary components constructed from stainless steel and are welded together. Alternative materials may, of course, be used, and if desired the funnel assembly may be manufactured (e.g. spun) as a single component.

The funnel assembly 402 is fitted with a plurality of water sprays 414. In this specific embodiment four sprays 414 are provided, evenly positioned around the circumference of the middle wall section 409 of the upper funnel segment 403, though additional or fewer sprays could be provided. Water sprays 414 are received in apertures (not shown) formed in the middle wall section and are approximately normal to the wall section 414. The water sprays used with the present embodiment have a spray angle of around 70 degrees and in use direct water into the funnel assembly and onto the underside of the hood assembly (discussed further below) to clean the inside of the hood assembly and prevent waste build-up thereon. A series of magnets 416 (e.g. rare earth magnets) are located around the outer surface of the funnel assembly 402. Magnets 416 are positioned around the circumference of the lower funnel segment 405 (specifically angled wall 412) in a zigzag type pattern selected so as to provide a relatively even magnetic field around the lower segment 405/wall 412). The magnets 416 are held in position by double sided tape, though alternative fixing means are of course possible. The magnetic field provided by magnets 416 turns the lower funnel segment 405 into a primary capture point or zone for capturing metallic objects (such as cutlery) in case such objects have inadvertently been introduced into the on-site organic waste receptacle 116 and end up in the processing unit 302.

The inside wall of the funnel assembly 402 is also provided with obstructions 419 (see Figure 4B) which disrupt the movement of organic waste in the funnel assembly 402 and prevent/reduce the likelihood of a vortex forming. In this embodiments two obstructions are provided, each being a rectangular prism in shape and approximately 100mm x 15mm x 15mm: obstruction 419A provided on the inside wall of the middle funnel segment 404, and obstruction 419B provided on the inside wall of the lower funnel segment 405. Additional or fewer obstructions, or obstructions of different shape and/or size, could of course be provided.

The funnel assembly 402 sits atop a bowl assembly 420 having an upper body 422 sitting atop a lower body 424. The upper body 422 provides a stator for the grinding rotor discussed below. The top of the upper body 422 defines an upper rim 426. The upper body 422 also includes a plurality of shoulders 428 extending outwardly from the outer surface away from the sides of upper body 422 (two of which are visible in Figure 4B). At its bottom the upper body 422 includes a lower apertured flange 430 which, when the processing unit 302 is assembled, abuts an upper apertured flange 432 of the lower bowl body 424.

The funnel assembly 402 is attached to the bowl assembly 420 by welding the lower flange 414 to the upper rim 426 of the upper bowl body 422, in addition to providing fasteners 434 which pass through corresponding pairs of apertures in the lower flange 442 and appropriately placed bores in the shoulder 426. With respect to the bowl assembly 420, the upper body 422 is secured to the lower body 424 by a series of fasteners 436, each fastener 436 passing through/received in an aperture 438 in flange 430 of the upper body 422 and corresponding aperture 440 in flange 432 of the lower body 424. Alternative and/or additional means for securing the various components of the processing unit together are, of course, possible.

The inner surface of the upper bowl body 422 is formed with a plurality of ridges 442, each ridge extending down the length (or a portion thereof) of the upper body 422 and protruding inwardly towards the centre of the bowl assembly 420. The ridges 442 are sized and shaped so as to provide edges/surfaces against which waste is comminuted by a grinding rotor which rotates within the bowl assembly 420 (and which is discussed further below). To assist with the communication process and agitation of the organic waste, the ridges 442 include a number of deep ridges 442A interspersed between shallow ridges 442B (the deep ridges 442A protruding further into the bowl body 422 than the shallow ribs 442B).

The lower bowl body 424 defines an annular channel 444 surrounding a central raised hollow 446. At one side of the lower body 424 the channel 444 feeds into a downwardly directed outlet 446 which, in this case, is integrally cast with the rest of the lower body 424. The mouth of the outlet 446 is provided with a fitting 448 for forming a fluid tight connection with the pump assembly 304. An opening 450 is also located in the wall of the lower bowl body 424, approximately above the centre of the mouth of outlet 446. Opening 450 receives a first pump assembly water supply line (see connecter 724 of the plumbing schematic depicted in Figure 7) which, in use, directs water into the pump assembly described below.

In the present embodiment the bowl assembly 420 sits atop an electric comminution motor 452. Suitable motors include those manufactured by CMG Engineering Group, with the specific power being selected according to the typical loads that will be collected in the receptacles 1 16 and delivered to the comminution unit 302. For example, a typical 120L wheelie bin may, when full, hold approximately 50kg of organic waste. In order to process this amount of waste a 4 kilowatt motor will typically be appropriate.

It is noted that the "bulk processing" of the presently described mobile waste treatment system is a difference to the typical processing patterns of waste treatment systems that are installed on-site. If the collection receptacles 1 16 used for the present invention are 120L wheelie bins, on each operational cycle the processing unit 302 will (generally, and depending on how full a given wheelie bin is) process around 50kg of waste.

A motor shaft 454 extends upwardly from the comminution motor 452 and couples with a drive shaft 456 via a drive shaft coupling 458. Drive shaft 456 is, in turn, coupled to and drives the actual waste processing means which, in this embodiment, includes a primary comminution means 460 and a pre-processing means 462. Shaft 454 defines an axis of rotation of the waste processing means. A motor locking pin 464 is also provided.

The primary comminution means 460 of the present embodiment is a cast rotor /grinding plate 466. An unobsciired top perspective view of rotor 466 is provided in Figure 4E (which, as described further below, illustrates a processing unit 302 which does not include the preprocessing means 462). The rotor 466 has a keyed central aperture through which the drive shaft 456 (which is complementally keyed to couple to the rotor) extends. The rotor 466 is positioned on the drive shaft 456 to be at the same height in the processing unit 302 as the ridges 442 of the bowl assembly 420. When the comminution motor 452 is operated the rotor 466 rotates about the axis of rotation within the bowl assembly 420 to comminute waste between the edge of the rotor 466 and the ridges 442.

The rotor 466 includes a plurality of apertures 468 through which comminuted waste and water can pass. The upper surface of the rotor 466 is provided with a pair of ridges 470 and 472 positioned diametrically opposite each other and extending radially from proximate the centre of the rotor 466 (or drive shaft 456/axis of rotation of the rotor) towards the perimeter of the rotor 466. Ridges 470 and 472 assist in directing food from atop the plate to the edges where it is comminuted. Ridge 472 further includes an upwardly directed protrusion 474 which further improves agitation and movement of organic waste to the periphery of the rotor 466. Proximate the central aperture, the upper surface of the rotor 497 is also provided with a pre-processor coupling formation 476. In this case the coupling formation 476 includes a plurality of rectangular teeth 478 annularly spaced around the central aperture of the rotor and extending vertically from the upper surface of the rotor 466. Teeth 478 engage with complementary teeth of the pre-processing means 462. The pre-processing means 462 of the present embodiment is a shredder assembly 480 having a hollow spindle 482 from which a plurality of arms 484 radially extend. In this instance four equi-angularly spaced (with respect to the axis of rotation) arms are provided, though in alternative embodiments fewer arms (e.g. 1 arm, 2 arms, or 3 arms) or more arms could be provided. Arms 484 extend approximately normally/perpendicularly to the axis of rotation and in this embodiment form a cross shape (centred on the spindle 482) having a relatively longer axis (made up of relatively longer arms 484A) and a relatively shorter axis (made up of relatively shorter arms 484B). The lengths of arms 484A and 484B could, of course, be equal. In order to reduce the likelihood of a vortex of organic waste forming (and reduce the load on the motor), the length of the arms 484 of the pre-processing means may be selected to provide a reasonable clearance between the ends of the arms 484 and the funnel wall. By way of example, for a funnel with a 450mm diameter (in the region of the arms 484), a clearance of approximately 40mm between the ends of the arms 484 and the funnel wall may be appropriate. Extending from the upper surface of each arm 484 is a pair of upwardly protruding arcuate vanes 486, each vane 486 being convex towards the spindle 482 (or, alternatively, concave towards the wall of the funnel assembly 402). As depicted in Figure 3D, which illustrates a top view of the shredder assembly 480, the vanes 486 are spaced along the arms 484 at different radial displacements from the axis of rotation A such that their leading edges trace different paths when the shredder 480 is rotated. This improves in agitating and shredding the organic waste. In this case the vanes 486 are positioned on the arms 484 such that corresponding opposite pairs of vanes 486A, 486B, 486C, and 486D trace four distinct circular paths on rotation: a path traced by the innermost vanes 486A on each of the relatively longer arms 484A; a path traced by the outermost vanes 486B on each of the relatively longer arms 484A; a path traced by the innermost vanes 4286C on each of the relatively shorter arms 484B; and a path traced by the outermost vanes 486D on each of the relatively shorter arms 484B. In alternative embodiments each different vane 486 may trace a different path, though in this case care needs to be taken that the arms are evenly balanced. In addition, a strengthening rib 488 extends along the length of each of two opposite arms.

The base of the spindle 482 has a toothed profile, the teeth being complementarily shaped to teeth 478 of the rotor 466. When assembled, the teeth of the spindle 482 engage with the teeth 478 of the rotor 266 such that rotation of the rotor 466 also results in rotation of the spindle 482 (and shredder 480). The top of the drive shaft 456 is threaded to receive a lock-nut 490 which secures the waste processing (being, in this instance, the primary comminution means 460 and pre-processing means 462) in place. The length of the spindle 282 is such that the shredder 480 sits above the bowl assembly 420 and primary comminution means 466 (i.e. inside the funnel assembly 402).

In use, the shredder 480 (or more generally the pre-processing means 462) is driven by motor 452 to rotate within the processing means about the axis of rotation. In this way the preprocessing means 462 rotates in the same plane as the primary comminution means 406. The arms 484 of the pre-processing means 462 act to downsize large pieces of organic waste, such as large pieces of fruit and vegetable. The pre-processing means 462 also downsizes green leaf matter (e.g. lettuce) which could otherwise simply sit in the funnel assembly 402 and not feed naturally through the primary comminution means 466 under gravity (potentially creating a blockage preventing comminution of organic waste placed in the unit). The arcuate vanes 486 assist in this process by grabbing and initially macerating the organic waste. In alternative embodiments pre-processor 462 component of the processing unit 302 may not be necessary. In this case, and as illustrated in Figure 4E, the drive shaft 456 is shorter in length such that the lock nut 490 secures against top of the rotor 466.

In further alternative embodiments, the waste processing means may be hydraulically driven rather than electrically driven. In this case a pressure sensor is used to determine the load on the hydraulic drive, the sensed pressure being usable to determine when the processing of organic waste has completed (as described below in relation to the load sensor used with the electric motor embodiment).

Pump assembly The pump assembly 304 will be now described in further detail with reference to Figures

5A to 5F. In this particular embodiment pump assembly 304 is housed inside the comminution unit 106, however the pump assembly 304 (or specific components there of, such as the pump mechanism) could of course be located outside the unit 106, for example mounted to the vehicle 102. The pump assembly 304 of the present embodiment is similar to the 415 volt three phase

MonoG60 pump manufactured by Monopumps, though improvements to the Mono G60 pump have been made to enhance its functionality for use with the organic waste treatment system.

Figure 5A provides a schematic depiction of pump assembly 304. Pump assembly 304 generally includes a pump motor 550, a pump suction chamber 502, and a worm drive assembly 554. A pump drive shaft 556 extends from the pump motor 550 and through the suction chamber 502. The motor 550 (and pump drive shaft 556 extending therefrom) and worm drive assembly form a pump mechanism. Pump drive shaft 556 engages with and drives a pump assembly macerator 558 and a worm drive rotor 560. Worm drive rotor 560 extends through a complementally shaped worm drive stator 562, both of which being housed in a pump assembly end cap 564. To facilitate reverse operation of the pump assembly 504 (described further below), a fastener 566 is used to secure the worm drive rotor 560 to the pump drive shaft 556. In this instance the fastener 566 is a grub screw. Multiple fasteners 566 may, of course be used, as could alternative fastening means. Various views of the pump suction chamber 502 are provided in Figures 5B to 5F - namely a perspective view in Figure 5B, a front view in Figure 5C, a top view in Figure 5D, a left elevation view in Figure 5E, and a sectional view in Figure 5F (taken along section A— A of Figure 5E). In these views "front", "left", and "bottom" are of course relative terms used for descriptive convenience.

The suction chamber 502 includes a body 504 defining a waste inlet 506, a suction chamber outlet 508, and a drive shaft opening 510. Waste inlet 506 includes a fitting 512 for engaging with fitting 448 of the bowl assembly 420 outlet 446. An apertured flange 14 is provided at the suction chamber outlet 508 for securing the suction chamber 502 to the pump assembly end cap 564. End cap 564 is provided with a waste outlet opening (not shown) which connects to waste transport line 310. An apertured flange 516 is also provided at the drive shaft opening 510 for securing the pump motor 550 to the suction chamber 502. Alternative fittings between the body 504 and connected components are, of course, possible.

Internally, and as can be seen in Figure 5E, the pump mechanism inlet 510 steps down to an internal pipe section 518 which extends into the internal chamber of the body 504 and through which the pump drive shaft 556 extends.

At its base the suction chamber 502 is provided with a threaded bore for removably receiving a sump 520. Sump 520 is fitted with a rare earth magnet (or magnets) to form a secondary capture point or zone for attracting and capturing any magnetic material (such as cutlery fragments) that may have passed through the comminution unit 106. This may occur where cutlery or other metallic objects are inadvertently placed in the comminution unit 106 and are not captured by the magnetised funnel assembly 402 (or the processing unit is in accordance with an embodiment that omits the feature of a magnetised funnel assembly 402).

The pump suction chamber 502 is also provided with a threaded water inlet bore 524 to which a second pump assembly water supply line is fitted (see connector 728 of the plumbing schematic shown in Figure 7). In operation, water is supplied through the bore 524 directly into the suction chamber 502, This assists in provide better suction, in particular where residual waste may be present in the suction chamber 502 which prevents or impedes water from the first pump assembly water supply line from reaching the suction chamber 502.

1 Once again, due to the relatively large volume of waste processed in the typical processing operation of the presently described mobile waste treatment system, a larger pump assembly (in terms of waste throughput) may be used than is generally used for installed waste treatment systems. This increased throughput may be provided by larger sized/diameter fittings and plumbing, and/or a larger pump motor. By way of non-limiting example, the pump assembly 304 according to one embodiment may have a throughput of around 200 Litres per minute.

Control unit

Operation of the comminution unit 106 is effected by control unit 306. In this embodiment control unit 306 is illustrated as being housed in the comminution unit 106, and while this will generally be convenient the control unit 306 could alternatively be provided elsewhere on the vehicle 102. Control unit 306 is, in this instance, a programmable logic controller (PLC) 602, though could of course be an alterative computer processing device.

As shown in Figure 6, which provides a logic block diagram comminution unit 106, the control unit 306 is connected to various components of the comminution unit 106 to enable communication of data (including, as appropriate, control signals and feedback data) between the control unit 306 and the relevant component. As illustrated, these connections include connections between the control unit 306 and:

• A control panel 604 including one or more controls 606 by which a user can control operation of the comminution unit, and a display 608 (such as an LED, LCD or other display) enabling the control unit 306 display operational information. The controls

606 and display 608 may be combined together in a touchscreen display. The control panel may be located on the comminution unit itself, or elsewhere on the vehicle as is convenient.

• A main water inlet valve 610, enabling the control unit 306 to control the supply of water during operation of the unit. The main valve 610 may be a solenoid valve.

• An auto cycle valve 612, enabling the control unit 306 to control supply of water during an automatic operational cycle. The auto cycle valve may be a solenoid valve.

• A wash cycle spray valve 614, enabling the control unit 306 to control supply of water during a wash cycle. The wash cycle valve may be a solenoid valve. • The comminution motor 452 of the processing unit 302, enabling the control unit 306 to activate/deactivate the comminution motor 452.

• A comminution motor load sensor 616, enabling the control unit 306 to receive information regarding the load (e.g. current) on comminution motor 452. Motor load sensor 616 may, of course, be an integral part of the comminution motor 452. If a hydraulic drive means is used, a pressure sensor may be used instead of the comminution motor load sensor 616.

• The pump motor 550, enabling the control unit 306 to activate and deactivate the pump assembly 304.

• A pump load sensor 618, enabling the control unit 306 to receive information on the load (e.g. current) of the pump motor 550. Pump load sensor 618 may, of course, be an integral part of the pump motor 550.

• A holding tank fail-safe sensor 622, enabling the control unit 306 to receive a signal that the holding tank is at capacity (or a signal from which this is determined) and all processing of waste should cease. The holding tank fail-safe sensor 622 may, for example, be a float switch.

• A access panel sensor 620, enabling the control unit 306 to receive a signal that an access panel of the comminution unit 106 (not shown) has been opened.

Operation of the comminution unit of the mobile waste treatment system will be described further below.

In this particular embodiment the control unit 306 is described as only controlling operation of the comminution unit 106. It will be appreciated, however, that in alternative embodiments the control unit 102 may be connected to additional components (e.g. the lifting assembly 104, and/or washing assembly 108) for their control as well.

Further, in alternative embodiments fewer, additional, or alterative components may be used and connected to the control unit 306. ¹ For example, comminution unit 106 is described as being configured with hardware and logic for performing a wash cycle. It, however, be the case that a wash cycle capability will not be necessary (the comminution unit instead being manually cleaned on a periodic basis). In this case, the wash cycle functionality (including the various wash cycle plumbing components as described below and the wash cycle logic) need not be included.

By way of further example, the holding tank 1 10 may be provided with a level/capacity sensor for sensing the remaining capacity of waste in the holding tank. In this case the holding tank sensor can also be connected to the control unit 306, enabling the control unit 306 to receive holding tank capacity information and allow/prevent operation of the comminution unit accordingly.

Comminution unit plumbing

Turning to Figure 7 the plumbing of the comminution unit 106 will be described. It will be appreciated, however, that the plumbing for the comminution unit 106 may be achieved in a number of different ways, using additional and/or alternative fittings and components to those described below.

The main water inlet 308 (which is connected to the water reservoir 112) leads to a pressure limit valve 706 which in this instance is a 500kpa pressure limit valve.

Pressure limit valve 706 is, in turn, connected to another tee fitting 708, one arm of which is connected to pressure switch 514. Pressure switch 514 is connected to the control unit 306 to provide information on the water supply pressure.

The other arm of fitting 708 is connected to the main water inlet valve 610. The main water inlet valve includes a line strainer. Downstream of the main water inlet valve is a further tee fitting 710, one arm of which leads to an automatic cycle valve 612 and the other to the wash cycle valve 614. The automatic cycle plumbing (i.e. the components downstream of the automatic cycle valve 612) include components to supply water to the water sprays 414 and the pump assembly 108. More specifically, the automatic cycle valve 612 connects to a needle valve 712, which in turn connects to a tee fitting 714. One arm of tee fitting 714 connects to sprays 414 (via a spray line including a 10mm push fit hose connection 716 and 10mm push fit tee connection 718). The other arm of tee fitting 714 connects to a further tee fitting 720. One arm of tee fitting 720 connects (via a 10mm push fit hose connection 722) a pump inlet hose 724. Pump inlet hose 724 is received by opening 450 and is for supplying water to the inlet of the pump assembly 108. The other arm of tee fitting 720 connects (via a 10mm push fit hose connection 726) to pump suction chamber inlet hose 728. Suction chamber inlet hose 728 is received at inlet bore 524 and is for supplying water directly to the pump suction chamber.

The wash cycle plumbing (i.e. the components downstream of the wash cycle valve 614) include components for supplying water to the water sprays 414. This includes a 10mm push fit hose connection 730 which in turn connects to a 10mm push fit tee connection 732 via which water is suppled to the sprays 414.

Four sprays 414 are provided, each spray being a 10mm push fit tee connecter connecting to spray line 734 and being fitted with a spray jet 736. As described above, the spray jets are positioned and have a spray angle to both supply liquid to the waste in the funnel assembly and to direct water onto the underside of the hood 312. In the present embodiment, each of the main water inlet valve 610, automatic cycle valve

612, and wash cycle valve 614 is a solenoid valve in communication with and controlled by control unit 306. Suitably, the plumbing fittings (such as tee connectors 702, 708, 712, 718) may be brass.

Operational logic Referring to flowcharts of Figures 10A to 10D, various operations of the comminution unit will be described. While the various steps of the flowcharts are depicted in a particular order, it will be appreciated that in many instances alternative orderings (or concurrent execution) of steps is possible, as is omission of some steps and/or inclusion of additional steps.

Automatic cycle Figure, 10A provides a flow chart 1000 depicting the operation of the comminution unit

106 during an automatic processing cycle. This cycle is generally suitable for processing a normal load of solid organic waste matter. At 1002 the control unit 306 receives the signal to commence the automatic cycle. In the present embodiment, commencement of the automatic cycle is achieved by activation of an automatic cycle control 606 (on control panel 604). In alternative embodiments, the control unit 306 may be configured to automatically commence activation of the automatic cycle when it is detected that a receptacle has been lifted to the tipping position.

At 1006 the control unit 306 checks that the water pressure is sufficient - i.e. that there is at least at a predefined water pressure threshold at the water supply line 112 (as reported by pressure switch 514). The predefined water pressure threshold may be 7 Bar.

At 1006, if the water pressure check 1004 fails (i.e. the pressure switch 514 reports that the water pressure is below the set threshold), the control unit 306 displays a water pressure error message (e.g. "Insufficient water pressure") on display 126, and flags a system fault at 1008.

If a system fault is flagged at 1008, the user can check undertake a manual system check at 1010, for example checking the water reservoir has water in it and pump 120 is operational. At 1012, once the manual check is complete the user can switch the comminution unit 106 off and back on to reset the system, and attempt to recommence the operation.

If the manual check at 1010 and reset at 1012 does not fix the problem, servicing of the comminution unit 106 may be necessary.

In some embodiments an additional check that a receptacle has been lifted to the tipping position may be performed. At 1013, if check 1004 is successful, the control unit 306 operates the pump motor 550 for a predetermined period of time (e.g. two seconds) in the reverse direction. This serves to dislodge any organic waste that may have remained in the pump assembly from a previous operational cycle.

At 1014 the control unit 306 commences the automatic processing cycle. This involves the control unit 306 opening the main water inlet valve 610 and the auto cycle valve 612. As shown in the plumbing schematic this supplies water to the sprays 414 and the pump assembly 304 (both into the pump inlet via opening 450, and directly into the pump suction chamber by opening 524). In the automatic cycle the control unit 306 also commences a grinder run cycle (by activation of the comminution motor 452), and commencing a pump run cycle (by activation of the pump motor 550).

At 1016, and during the processing cycle, the control unit 306 monitors the load on the comminution motor 452 (via the motor load sensor 616) and the load on the pump motor 550 (via the pump load sensor 618) to determine whether either are overloaded. A comminution motor overload is detected if the load on the comminution motor 452 is reported as exceeding a predefined comminution load threshold. Similarly, a pump overload fault is detected if the load on the pump motor 550 is reported as exceeding a predefined pump threshold.

In the present embodiment: a comminution motor overload is detected where the comminution motor operates 10% over the rated motor current for more than 2 seconds; a pump motor overload is detected where the pump motor the pump motor operates at the rated motor current for more than 2 seconds.

The relationship between the load on the comminution motor 452 and the volume of water added during the cycle can be varied according to the desired properties of the resulting slurry. For example, the relationship may be set so as to produce a slurry having (or approximately having) a defined pulp density or range of pulp densities, a defined moisture content or range of moisture contents, or a defined flow characteristic or range of flow characteristics. By way of example, the comminution unit may operate to produce slurry with a weight of about 1.1 tonne per cubic meter, and a moisture density of 75-85%. The control unit 306 maintains a fault counter of the number of overload faults that have occurred in succession. On first operation of the unit 106 (or first operation of the unit 106 after a service reset) the fault counter is initialised at zero.

If the control unit 306 detects an overload in either the comminution motor 452 or pump motor 550, the control unit 306 increments the fault counter, and at 1018 compares the value of the fault counter to a predetermined maximum fault number (for example, three faults).

If the value of the fault counter is less than the maximum fault number, the control unit 306 displays a fault error message on display 1008 at 1020. If the comminution motor fault threshold is exceeded the error message may be "Grinder overcurrent" or similar. If the pump mechanism fault threshold is exceeded the error message may be "Pump overcurrent". The cycle is stopped at 1022 (i.e. the control unit 306 terminates operation of the comminution motor 452 and pump motor 550), a fault is logged at 1008, and the user may manually check and reset the system at 1010 and 1012 respectively before attempting to recommence the operation cycle. In addition, on detection of a comminution or pump overload event the control unit 306 may at 1020 communicate the occurrence of the event to one or more entities as discussed below (e.g. by sending an SMS message to the entity responsible for maintenance of the unit).

If the value of the fault counter is equal to the maximum fault number, the control unit 306 displays an overload error message on display 608 at 1024 and stops the cycle at 1026. In this case further operation of the comminution unit 106 is prevented, and servicing of the unit 106 may be required before the unit 106 can be operated again.

If no faults are detected the operational cycle completes at 1028. In one embodiment, completion of the operating cycle is detected where the control unit 306 detects that the load on the comminution motor 452 stays below a predefined minimum load threshold for a predetermined period of tirne.^ The predefined minimum load threshold for the comminution motor 452 may be automatically adjusted according to the load sensed during a wash cycle (as described below), and the predetermined time period may be 5 seconds. In alternative embodiments, an operational cycle timeout may be used to determine completion of an operational cycle - i.e. on commencement of a cycle a timer starts, and when the timer reaches the operational cycle timeout the cycle will complete. In some implementations the cycle timeout may be made dependent on the capacity and/or waste of the receptacles 116 used with the system. For example, relatively dry waste (such as that collected from bakeries, which is predominantly bread/flour etc) typically takes longer to process than relatively wet waste (such as that collected from fruit shops, which is predominantly fruit/vegetables). Accordingly, the operational cycle timeout for bakery waste may be set at a longer interval than the operational cycle timeout for fruit and vegetable shop waste.

At completion of the operational cycle the control unit 306 deactivates the comminution motor 452 and pump motor 550, and resets the fault counter to zero. The control unit 306 also closes the main and automatic cycle water valves 610 and 612.

If the comminution unit enters lock down mode as indicated by 1026 (e.g. due to the predefined number of overload faults being reached at 1024), any operational cycle in progress is immediately interrupted/ceased, and further operation of the comminution unit 106 is prevented. At this point service of the unit 106 may be required.

Liquid cycle

Figure 10B provides a flow chart 1050 depicting the operation of the waste comminution unit 106 during a liquid processing cycle. This cycle is suitable if the organic waste in the receptacle is entirely or predominantly liquid.

At 1052 the control unit 306 receives the signal to commence the liquid cycle - e.g. on activation of a liquid cycle control 606 (on control panel 604).

On activation of the liquid cycle control, the control unit 306 checks the water pressure. This check (and downstream steps) are as per steps 1004 to 1012 of the automatic cycle and will not be described again here.

At 1054 the control unit 306 commences the liquid processing cycle which involves the control unit 306 operating the pump motor 550 for a predetermined period of time (e.g. 10 seconds). After operating the pump mechanism for the predetermined period of time, the liquid cycle completes at 1056, and the control unit 306 deactivates the pump mechanism motor 550.

Wash cycle

In some embodiments the comminution unit may also be configured to perform a wash cycle. Figure IOC provides a flow chart 1070 depicting the operation of the comminution unit 106 during a wash cycle. This cycle is suitable for cleaning the comminution unit 106 when required (for example at the end of a days processing).

At 1072 the control unit 306 receives the signal to commence the wash cycle - e.g. on activation of a liquid cycle control 606 (on control panel 604).

On activation of the wash cycle control, the control unit 306 checks that the water pressure. This check (and downstream steps) are as per steps 1004 to 1012 of the automatic cycle and will not be described again here. At 1074 the control unit 306 commences the wash cycle at 672 by operating the main water valve 610 and the wash cycle valve 614, thereby supplying water to the sprays 414, for a set period of time.

On completion of the spray operation, the control unit 306 delays for a set period (e.g. 2 seconds), and then at activates the comminution motor 452 and pump motor 550 for two cycles of predetermined time (e.g. 10 seconds).

At 1078 the control unit 306 terminates operation of the comminution motor 452, but continues to operate sprays (i.e. by leaving the main and wash cycle valves 610 and 614 open) and the pump motor 550. At 1080 the wash cycle terminates, and the control unit 306 closes the main and wash cycle valves 610 and 614 and terminates operation of the pump motor 550.

Emergency stop

Figure 10D provides a flow chart 1080 depicting the operation of the waste processing system on activation of emergency stop control. At 1082 the control unit 306 receives an emergency stop signal caused by a user activating an emergency stop control .

At 1084 the control unit 306 isolates the comminution unit 106 and enables category 4 safety. Any open valves (e.g. the main, automatic cycle, and wash cycle valves 610, 612, and 14) are closed. At 1086 the control unit 306 displays an emergency stop message on the display 608 (e.g.

"Emergency stop activated").

Comminution motor and pump motor thresholds

In one embodiment, the minimum load thresholds (or reference values from which these thresholds can be determined) for the comminution motor 452 and pump motor 550 are obtained by operation the comminution unit 106 without any solid waste. For example, the control unit 306 may monitor the loads on the comminution motor 452 and pump motor 550 when operated (without any solid waste to be processed) for a predetermined time, and use these values as the minimum load threshold. As described above (e.g. in the automatic cycle), the minimum load thresholds are then used to automatically determine the complete on of an operational cycle.

Calibration of the minimum load thresholds may be performed on initial setup of the system 100, and re-performed periodically over the life of the unit 106. Holding tank monitoring

In embodiments where a holding tank 110 level/capacity sensor is used (e.g. fail safe sensor 622), if at any point the control unit 306 receives a signal that the holding tank has reached capacity the control unit 306 will preveni/cease operation of the comminution unit 106.

Washing assembly The washing assembly 108 of the present embodiment is a steam pressure washing assembly. Suitable steam pressure washing assemblies include those supplied by Steammaster. For example, a 1500 PSI hot water pressure washer may be used that could be powered by fuel (e.g. diesel). Alternatively, a standard 1500PSI pressure washer could be used, with hot water supplied from the exhaust manifold of the vehicle. Referring to Figure 8, the washing assembly 108 generally includes a washing assembly pump/water heater 802 connected to the water reservoir 112 by pipe/hose 118, and a water lance 322 connected to the pump/water heater 802 via a hose 804.

A lance actuator 806 is also provided for extending retracting the water lance 322. Extension/retraction of the lance is along an axis of the lance 322, in the directions indicated by arrows 808 and 810 respectively.

The lance 322 is positioned to extend through the wiper seal 320 in the hood 312. The distal end of the lance 322 is fitted with a spray assembly 812. In the present embodiment the spray assembly 812 includes five spray heads which are configured, in use, to spray water onto the four internal walls and the bottom/base of receptacle 116. Normally, the lance 322 is held in a retracted position, for example as shown in Figures

2 A and 2B. In this position the lance 322 extends only minimally into the hood 312. In use, once a receptacle 116 has been lifted to the tipping position, the lance actuator 806 is operated to extend the lance into the extended position as shown in Figure 2C (in which the lance 322 is positioned inside the receptacle 116) and then retract the lance back to the retracted position.

During the extension/retraction stroke of the lance, the washing assembly pump/water heater 802 are operated to spray hot water/steam through the spray assembly 812 and into the receptacle. The five nozzles of the spray assembly spray water on each of the four side walls of the receptacle 116 and the base of the receptacle 116 as the lance 322 moves in and out of the receptacle 1 16. This serves to wash out any organic material that hasn't fallen out of the receptacle 1 16 naturally, and to clean the receptacle 1 16.

In one embodiment the lance 322 is approximately 700 cm long, though the actual length may be adjusted according to the on-site waste receptacles 1 16 used. The lance actuator 806 is a pneumatic cylinder which, in conjunction with a 700mm lance, has approximately a 600mm stroke. Extension and retraction of the lance 322 is limited by two blow-off limit switches.

The washing assembly pump/water heater 802 and lance actuator 806 are connected to and powered by the power supply 1 14. In the present embodiment, operation of the washing assembly 108 is automatic. When the receptacle 1 16 is detected to be in the tipping position (e.g. due to a receptacle position sensor or a signal sent from the lifting assembly), the lance actuator 806 and pump/water heater 802 are automatically operated to spray water/steam through the lance 322 and extend the lance 322 into the receptacle. This extension operation may be on a time delay in order to provide time for the organic waste stored in the receptacle 116 to fall out prior to the lance 322 being extended. The lance 322 extends until it reaches the end of the pneumatic cylinder stroke and then returns to the retracted position. Once the lance 322 is back in the retracted position the pump/water heater 802 are deactivated.

By automatically washing the on-site receptacles 1 16 as part of the organic waste collection process, the receptacles 116 are kept clean, and the need for plastic bags or other bin liners is avoided.

Holding tank

Turning to Figures 9A and 9B holding tank 110 and its mounting to vehicle 102 will be described. Figure 9A is a perspective diagram showing the mounting of the tank 110 to a vehicle subframe 902, and Figure 9B is an enlarged partial perspective view of one foot of the holding tank 1 10 mounted to the subframe 902.

The holding tank 110 of the present embodiment is roughly cylindrical and includes a plurality of legs 904 (in this case four). Each leg 904 extends across a width of the tank 110, and is provided at either end with a hold down pin 908 by which the tank 110 is secured to the subframe 902.

The top of the tank 110 is provided with an access hatch 910 by which the tank can be inspected and cleaned. The tank 110 is also provided with at least one sight-tube 912 to allow operators to easily determine the level of slurry in the holding tank 110. In order to work effectively with the relatively viscous liquid slurry to be held by the tank 110, the sight-tube used is a relatively wide diameter (e.g. 3-4 inch) transparent pipe connected at a base and top of the tank 110. If desired additional (or alternative) level or capacity sensing means may be used to prevent or reduce the likelihood of the tank 110 being overfilled.

The tank is also provided with a waste inlet pipe/coupling 914 at an upper region of the rear wall of the tank for connecting to the comminution unit 106 via a pipe or hose. A waste outlet pipe/coupling 924 (e.g. a 3-4 inch camlock) is also provided at the bottom of the tank via which the holding tank 110 can be emptied.

As can be seen, the subframe 902 includes a support spine 916 that runs centrally along the length of the holding tank 110, and a plurality (again, in this case four) leg supports 918 which run perpendicular to spine 916 and correspond to the legs 904 of the holding tank 1 10. Each end of each leg support 918 is provided with a pair of lateral leg stops 920 which sit on either side of the tank legs 904 and prevent lateral movement of the tank 110.

As can be most clearly seen in Figure 9B, in order to secure the tank 110 to the subframe 902, high tensile hold down bolts 922 (e.g. M10 bolts) are passed through either end of the hold down pins and received in the subframe 902.

In the present embodiment the holding tank 110 is a 5000 litre molasses grade plastic tank as supplied, for example, by Allquip. Alternative tanks or tank materials (e.g. steel or aluminium) could be used. In order to reduce movement of the liquid slurry in the holding tank 110 during movement of the vehicle 102, a fluid movement reduction means may be used. One such means includes adding a plurality of ball baffles to the holding tank 110, such as the rapid spray ball baffles distributed by Tank Management Services Pty Ltd. Water reservoir

Water reservoir 112 may be made of any suitable material, for example plastic or aluminium, and may be mounted directly to the vehicle chassis or to a subframe/flatbed. The water reservoir 1 12 is connected to the comminution unit 106 via pipe/hose 122.

A pump 120 is used to pump water from the reservoir 112 to the comminution unit 106 when needed. Pump 120 may, for example, be a small pressure pump such as those manufactured by Mono connected to and powered by the power supply 114.

Pump 120 is activated via a pressure switch which automatically detects operation of the comminution unit 106 (e.g. opening of the main water inlet valve 610 and automatic cycle valve 612, or opening of the main water inlet valve 610 and wash cycle valve 614) and supplies water accordingly.

While it will generally be convenient for the vehicle 102 to carry its own water reservoir as described, it will be appreciated that in some embodiments this will not be essential, and water can be accessed from the various collection sites - e.g. via a mains water tap or other water reservoir. In this instance vehiclel02 will be provided with relevance hoses/couplings to connect to on site water supplies, and/or a pump for pumping water from the on-site supply to the comminution unit 106 and washing assembly 108.

Power supply

The powered components of the mobile organic waste treatment system 100 are connected to and powered by the power supply 114. These components include the lifting assembly 104, the comminution unit 106, the washing assembly 108, and pump 120.

In one embodiment the power supply 1 14 is a power generator such as the QD 5000 diesel generator supplied by Cummins Onan. In alternative embodiments, powered components may alternatively be powered by the motor of the motor vehicle. This may be appropriate for components with relatively low level power requirements such as pump 120 between the water reservoir 112 and the comminution unit 106. Hopper and feeding means

In the above description (and referring to Figures 2 and 3 in particular), the comminution unit 106 is depicted with a hood 312, and organic waste is tipped directly into the funnel of the comminution unit (via the hood) for processing. In some instances commencing operation of the comminution unit 106 (and in particular the comminution motor 452) after the entire contents of a receptacle 1 16 have been emptied into the unit 106 results in a relatively high load being placed on the motor 452. This relatively high load may be undesirable due to overload the motor 452 or the power supplyl 14.

To address this issue, in some embodiments organic waste may be fed into the comminution means in a more controlled manner. By way of one example, Figure 1 1 depicts schematically a hopper and feeding means for achieving this, and Figure 12 depicts a mobile unit 1200 incorporating the hopper and feeding means of Figure 11.

In the embodiment of Figures 11 and 12, hood 312 is fitted to a hopper 1102 instead of to the comminution unit 106. The hopper 1102 is provided with a feeding means 1104 which extends from the hopper 1 102 to the comminution unit 106 (as indicated by broken line 1 106). In one embodiment the feeding means 1104 is a screw auger, powered by a feeding means motor 1108 (the feeding means motor 1 108 being connected, in turn, to the power supply 114).

Alternative feeding means, for example a conveyor belt type arrangement, could be used.

In operation, the receptacle 116 is lifted into the tipping position (and the washing assembly 108 operated) as described above. In the tipping position, however, organic waste from the receptacle 116 is emptied into the hopper 1102 instead of being deposited directly into the comminution unit 106.

The feeding means 1104 is then operated to feed the organic waste to the comminution unit 1 6 in a controlled manner. In the illustrated schematic the feeding means 1104 feeds the waste to the comminution unit 105 though an opening in a side wall of the funnel assembly 402. A lid 1110 is provided to seal the top of the funnel assembly 402.

The rate at which the feeding means 1104 is configured to deliver organic waste to the comminution unit 106 will depend on the size of the comminution unit and comminution/pump motors used. By way of example, where a 4kw comminution motor is used, the feeding means may be configured to deliver organic waste at a feed rate of around lK.g per second - though it will be appreciated that the actual rate will be highly dependent on the type of waste.

The feeding means 1104 may be manually controlled (i.e. by an on/off button), or may be configured to be operated automatically. For example, the feeding means may be connected to a central controller which commences operation of the feeding means 1104 on a receptacle being lifted into the tipping position (detected either by a dedicated tipping position sensor or a signal from the lifting means 104), or on the commencement of a comminution unit operational cycle. Operation of the feeding means 1104 may then be terminated after a predetermined period of time has passed, or on termination of a comminution unit operational cycle (as described above). It will be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evidence from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.

The foregoing describes embodiments of the present invention and modifications obvious to those skilled in the art can be made thereto without departing from the scope of the present invention.

Claims

1. A mobile organic waste treatment system including: a vehicle carrying: a power supply; a hopper for receiving organic waste from an organic waste receptacle; a comminution unit for receiving the organic waste from the hopper and reducing the volume of the organic waste by comminuting the organic waste with water from a water reservoir to form a liquid slurry, the comminution unit being connected to and supplied with power from the power supply; a holding tank in fluid communication with the comminution unit to receive the liquid slurry therefrom; a washing assembly for washing the organic waste receptacle with water from the water reservoir; and a feeding means for feeding the organic waste from the hopper to an inlet of the comminution unit in a controlled manner.

2. A mobile organic waste treatment system according to claim 1, wherein the vehicle carries a lifting assembly for lifting the organic waste receptacle into a tipping position in which the organic waste is tipped into the hopper.

3. A mobile organic waste treatment system according to claim 2, wherein operation of the feeding means is automatically commenced when an organic waste receptacle is lifted into the tippmg position by the lifting assembly.

4. A mobile organic waste treatment system according to claim 2 or claim 3, wherein operation of the feeding means is automatically terminated on completion of an operational cycle of the comminution unit.

5. A mobile organic waste treatment system according to claim 2 or claim 3, wherein operation of the feeding means is automatically terminated after a predetermined period of time.

6. A mobile organic waste treatment system according to any one of claims 1 to 5, wherein the feeding means is a screw auger extending from an outlet of the hopper to the inlet of the comminution unit.

7. A mobile organic waste treatment system according to any one of claims I to 5, wherein the feeding means is a conveyor extending from an outlet of the hopper to the inlet of the comminution unit.

8. A mobile organic waste treatment system according to any one of claims 1 to 7, wherein the water reservoir is carried by the vehicle and is in fluid communication with the comminution unit and the washing assembly.

9. A mobile organic waste treatment system according to any one of claims 1 to 8, wherein the vehicle further carries a main pump assembly for pumping water from the water reservoir to one or more of the comminution unit and the washing assembly .

10. A mobile organic waste treatment system according to any one of claims 1 to 9, wherein the washing assembly includes a heater for heating water from the water reservoir.

11. A mobile organic waste treatment system according to any one of claims 1 to 10, wherein the washing assembly includes a lance fitted at one end with a spray assembly for spraying water into the organic waste receptacle, the lance being connected to the water reservoir.

12. A mobile organic waste treatment system according to claim 11, wherein the lance is mounted via a lance actuator, the lance actuator being configured to move the lance between an extended position in which the lance extends into the organic waste receptacle and a retracted position in which the lance is retracted out of, or substantially out of, the organic waste receptacle.

13. A mobile organic waste treatment system according to claim 1 1 or claim 12, wherein the washing assembly includes a washing assembly pump for pumping water from the water reservoir to the lance.

14. A mobile organic waste treatment system according to any one of claims 11 to 13 when dependent on claim 2, wherein when the organic waste receptacle is lifted into the tipping position the actuator is automatically operated to move the lance to the extended position.

15. A mobile organic waste treatment system according to any one of claims 11 to 14 when dependent on claim 2, wherein when the organic waste receptacle is lifted into the tipping position the washing assembly pump is automatically operated to spray water out of the spray assembly and into the organic waste receptacle.