TECHNICAL FIELD

A compaction machine, and waste management facility and method are disclosed. The waste management facility and method may involve the harvesting of methane/bio gas from compressed garbage including garbage compressed by the disclosed compaction machine.

BACKGROUND ART

Household and other commercial (i.e. from restaurants, abattoirs, shops etc, and other non building rubbish) rubbish is traditionally collected and transported by trucks. The collected rubbish may be subjected to some form of recycling or sorting. Subsequently the rubbish is traditionally dumped into large ravines, old mine sites, quarry sites or other dedicated land holdings. The rubbish may be spread over the dump area and compacted by heavy machines such as a bulldozer or roller. Sand may then be pushed over the rubbish to assist with the compaction and create a filter to minimise odours exuding from decomposing rubbish. This process may continue until dump area is full.

The above existing method is recognised as problematic for multiple reasons including but not limited to contamination of the environment and in particular underground water systems, and the continued need for vast areas of land.

SUMMARY OF THE DISCLOSURE

In broad and general terms, the present disclosure relates to a compaction machine that may compact material such as rubbish into a block. In some embodiments the bock is formed with at least one face that is recessed or otherwise profiled to enables blocks to be stacked one against the other in a manner creating voids between the blocks. This in turn can create a network of fluid flow paths within for example a pit in which the blocks are stacked. The creation of the fluid flow paths may provide multiple benefits in terms of waste management. These include but are not limited to: increasing methane/bio-gas production or production rates; facilitating heat transfer to and from the pit; and collection of liquids from the pit.

In one aspect there is disclosed a compaction machine comprising:

a housing having or forming a chamber for holding a volume of material and at least a first ram arrangement operable to compact the material into a compressed block of material, the first ram arrangement provided with a contact face for contacting the material in the chamber, the contact face having non planar and protruding profile wherein the compressed block of material is formed with at least one side having a recessed face by application of pressure by the contact face.

In one embodiment the first ram arrangement comprises one or more first rams and a wear block demountably coupled to the one or more first rams, wherein the contact face is a face of the wear block.

In one embodiment the machine comprises a second ram arrangement operable to compress the material in the chamber and wherein the first and second ram arrangements are arranged to compress the material in mutually non-parallel directions.

In one embodiment the first ram arrangement is operable to compress the material in a first linear direction and the second ram arrangement is operable to compress the material in a second direction orthogonal to the first direction.

In one embodiment in the second ram arrangement includes a press plate movable to a location within the chamber to form a bearing surface for the wear block.

In one embodiment a press plate mechanical locking system arranged to mechanically lock the press plate at the location.

In one embodiment a third ram arrangement arranged to compress the material in an arcuate direction.

In one embodiment the second ram arrangement is translated by the third ram arrangement from a first position where the chamber is open and able to receive a charge of material and a closed position from which the second ram arrangement is operable to compress the material in the second direction.

In one embodiment the machine comprises a swinging wall coupled to and arranged to move in the arcuate direction by, the third ram arrangement.

In one embodiment the swinging wall mechanical locking system arranged to mechanically lock the swinging wall in closed position. In one embodiment the machine is arranged to compress the material by sequential operation of the third ram arrangement, the second ram arrangement and lastly the third ram arrangement.

In one embodiment comprises a second ram arrangement and a third ram arrangement wherein the ram arrangements are operable to compress the material by sequential application of pressure in an arcuate direction and each of two mutually orthogonal directions.

In one embodiment the contact face comprises a compound surface having a non-planar surface and a least one or more additional surfaces protruding from the non-planar surface.

In one embodiment the non-planar surface has a generally convex profile.

In one embodiment the one or more additional surfaces have a substantially hemispherical profile.

In one embodiment comprises a thermal regulating system arranged to control temperature of material in the chamber.

In one embodiment the thermal regulating system includes a heat exchanger system arranged to maintain the heat of material within a selectable temperature range.

In one embodiment the temperature range is between 50°C and120°C.

In one embodiment the heat exchanger system comprises a first heat exchanger in physical contact with the housing and remote heat exchanger located remote from and a heat transfer fluid circulating through and between the first heat exchanger the remote heat exchanger.

In one embodiment comprises a liquid extraction system arranged to remove liquid in the chamber.

In one embodiment the liquid extraction system comprises one or more liquid drainage ports in a base of the chamber. In one embodiment the liquid extraction system comprises a relative negative pressure source in fluid communication with the one or more liquid drainage ports for applying a relative negative pressure to the chamber.

In one embodiment the machine is operable to automatically open or close the ports dependent on a position of the contact face within the chamber.

In a second aspect there is disclosed a compaction machine comprising:

a housing having or forming a chamber for holding a volume of material to be compressed; an arrangement of rams operable to compress material by sequential application of pressure in a plurality of directions; and

a liquid extraction system arranged to remove liquid in the chamber.

In one embodiment the liquid extraction system comprises one or more liquid drainage ports in a base of the chamber.

In one embodiment liquid extraction system comprises a relative negative pressure source in fluid communication with the one or more liquid drainage ports for applying a relative negative pressure to the chamber.

In one embodiment the machine is operable to automatically open or close the ports dependent on a position of the contact face within the chamber.

In one embodiment the machine comprises a thermal regulating system arranged to control temperature of material in the chamber.

In a third aspect there is disclosed a compaction machine comprising:

a housing having or forming a chamber for holding a volume of material to be compressed; an arrangement of rams operable to compress material by sequential application of pressure in a plurality of directions; and

a thermal regulating system arranged to control temperature of material in the chamber.

In one embodiment the plurality of directions includes an arcuate direction and at least one linear direction. In one embodiment plurality of ram arrangements can comprise the first ram arrangement having one or more first rams and a wear block demountably coupled to the one or more first rams, wherein the contact face is a face of the wear block.

In one embodiment the plurality of ram arrangements comprises a second ram arrangement operable to compress the material in the chamber and wherein the first and second ram arrangements are arranged to compress the material in mutually non-parallel directions.

In one embodiment the first ram arrangement is operable to compress the material in a first linear direction and the second ram arrangement is operable to compress the material in a second direction orthogonal to the first direction.

In one embodiment in the second ram arrangement includes a press plate movable to a location within the chamber to form a bearing surface for the wear block.

In one embodiment comprises a press plate mechanical locking system arranged to mechanically lock the press plate at the location.

In one embodiment the plurality of ram arrangements comprises a third ram arrangement arranged to compress the material in the arcuate direction.

In one embodiment the second ram arrangement is translated by the third ram arrangement from a first position where the chamber is open and able to receive a charge of material and a closed position from which the second ram arrangement is operable to compress the material in the second direction.

In one embodiment the machine comprises a swinging wall coupled to and arranged to move in the arcuate direction by, the third ram arrangement.

In one embodiment the machine comprises a swinging wall mechanical locking system arranged to mechanically lock the swinging wall in closed position.

In one embodiment the machine is arranged to compress the material by sequential operation of the third ram arrangement, the second ram arrangement and lastly the third ram arrangement.

In a fourth aspect there is disclose a method of harvesting gas from organic waste material comprising compressing organic material into a plurality of blocks wherein each block has a first face formed with a recess; stacking the blocks so that the first face of one block faces a face of an adjacent block to form a cavity therebetween, and wherein the cavities are aligned to form channels extending between a plurality of layers of stacked blocks enabling gases produced by the material to flow to one or gas collection conduits through which the gas may be communicated to a remote location.

In one embodiment stacking the blocks comprises stacking the blocks so that the first face of one block faces the first face of an adjacent block.

In one embodiment the method comprises stacking the blocks in one or more a liquid and gas impervious pits.

In one embodiment the method comprises providing a liquid collection system arranged to direct liquid seeping from the material to a remote processing location.

In a fifth aspect there is disclosed a method of processing household garbage comprising collecting garbage from household garbage bins; processing the garbage to remove non- organic material and produce particulate organic material; compressing the particulate organic material into blocks wherein each block as at least a first recess face.

In a sixth aspect there is disclosed a method of processing household garbage comprising collecting garbage from household garbage bins; processing the garbage to remove non- organic material and produce particulate organic material; compressing the particulate organic material into blocks wherein the material in each block is compressed by a ratio of between 15:1 to 70:1 or more.

In one embodiment of the sixth aspect the method comprises using the machine of any one of the first to third aspects to compress the material.

In a seventh aspect there is disclosed a waste management facility comprising:

a compaction machine according to the first to third aspects;

one or more pits for holding one or more blocks of material compressed by the compaction machine; and

a heat exchanger system enabling exchange of heat between the compaction machine and the blocks of compressed material held in the one or more pits.

In one embodiment each of the one or more pits is provided with a liquid and gas impervious lining to prevent uncontrolled escape of liquid or gas from the pits.

In one embodiment the facility comprises one or more pipes or conduits disposed in the pit for collecting gas generated by material in the pit. In one embodiment the facility comprises a negative pressure source for applying negative pressure to the pits to facilitate a flow of gas through the one or more pipes to a remote location.

In one embodiment each pit comprising a corresponding liquid and gas impervious roof or cover.

In one embodiment the facility comprises a sealing system to form a gas tight seal between the roof and the pit.

In an eighth aspect there is disclosed a waste management facility comprising:

a compaction machine according to any one of the first to third aspects;

one or more pits for holding one or more blocks of material compressed by the compaction machine;

wherein each of the one or more pits is provided with a liquid and gas impervious lining to prevent uncontrolled escape of liquid or gas from the pits.

In one embodiment the facility comprises an arrangement of gas pipes disposed in the pit for collecting gas generated by material in the pit.

In one embodiment the facility comprises a negative pressure source for applying negative pressure to the pits to facilitate a flow of gas through the arrangement of gas pipes to a remote location.

In one embodiment each pit comprises a corresponding liquid and gas impervious roof or cover.

In one embodiment the facility comprises a sealing system to form a gas tight seal between the roof and the pit.

In a ninth aspect there is disclosed a waste management facility comprising:

one or more pits formed with a liquid and gas impervious surface arranged to prevent uncontrolled escape of gas or liquid through the surface;

an arrangement of gas pipes located in the pit for receiving gas generated by decomposition material held in the one or pits and transferring the gas to a first remote location; and one or more liquid pipes or conduits arranged to collect liquid emanating from material within the pit and transferring the collected liquid to a second remote location.

In a tenth aspect there is disclosed an energy generation system comprising: a compaction machine according to any one of claims 1 -40 operated to produce compressed blocks of organic material;

one or more substantially sealed pits for holding one or more the blocks of material; and an arrangement of gas pipes located in the one or more pits for receiving gas generated by decomposition of the material held in the one or pits and transferring the gas to a first remote location; and

a heat exchanger system arranged to control temperature within the one or more pits.

BRIEF DESCRIPTION OF THE DRAWINGS Notwithstanding any other forms which may fall within the scope of the machine, facility, systems and methods as set forth in the Summary, specific embodiments will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a side view of an embodiment of the disclosed compaction machine;

Figure 2 is a top view of the compaction machine shown in Figure 1 ; Figure 3 is a front view of the compaction machine shown in Figure 1 ;

Figure 4 is a rear view of the compaction machine shown in Figure 1 , and showing a ram arrangement in two different locations;

Figure 5 is a perspective view from one angle of the compaction machine shown in Figure 1 ;

Figure 6 is a perspective view from another angle of the compaction machine shown in Figure 1 ;

Figure 7a is a front view of a wear block and associated contact face incorporated in an embodiment of the disclosed compaction machine;

Figure 7b is a perspective view from a side angle of the wear block shown in Figure 7a;

Figure 7c is a perspective view from an orthogonal side angle of the wear block shown in Figure 7a;

Figure 7d is a front perspective view of the wear block shown in Figure 7a;

Figure 7e is a rear perspective view of the wear block shown in Figure 7a;

Figure 8 is a schematic representation of a waste processing facility incorporating an embodiment of the compaction machine; Figure 9a is a perspective view of a block of material compacted by an embodiment of the disclosed compaction machine;

Figure 9b is representation of two blocks of material compacted by an embodiment of the disclosed compaction machine arranged in a face-to-face configuration;

Figure 9c is a perspective view of a block of material compacted by a further embodiment of the disclosed compaction machine;

Figure 10 is a schematic representation of a first embodiment of the disclosed waste storage and methane production facility; and

Figure 1 1 a schematic representation of a second embodiment of the disclosed waste storage and methane production facility.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS Broad Description of compacting machine

With reference to Figures 1 -6 an embodiment of the disclosed compaction machine 10 (hereinafter referred to in general as“machine 10”) comprises a housing 12 having or forming a chamber 14 for holding a volume of material to be compact. As discussed in greater detail later, the material may be in the form of garbage. The garbage may be subjected to a prior sorting process and/or shredding or grinding so that the material is in a particulate form when entering the machine 10. However, it is to be understood that the structure, functionality, and operation of the machine 10 is independent of the type of material being compacted.

The machine 10 has a plurality of ram arrangements that operate to compact the material entering the chamber 14. The ram arrangements operate in different directions to compact the material. In one embodiment the compacted material exits the machine 10 substantially as a single block of compressed material. Further, in one, but not necessarily all embodiments, the compressed block is formed with at least one face having at least one recess or concavity.

The ram arrangements include a first ram arrangement 16 provided with a contact face 18 for contacting the material in the chamber 14. The first ram arrangement 16 provides a third or final stage of compression by compressing the material in the chamber 14 in a first direction D1 . In this embodiment, and as shown most clearly in Figures 7a-7e, the contact face 18 has a non-planar and protruding profile. In broad and general terms this profile may be classified as a generally parabolic convex profile. In the compaction process the contact face 18 transmits pressure from the first ram arrangement 16 to compress the material to thereby form at least one recess in the compressed block of material.

The ram arrangements also include a second ram arrangement 20 that operates in a non parallel direction relative to the first ram arrangement 16 to compact material in or into the chamber 14. More specifically the second ram arrangement 20 compresses material in a second direction D2 which is orthogonal to the direction D1 of compaction of the first ram arrangement 16. The second ram arrangement provides a second stage of compression.

The machine 10 also has a third ram arrangement 22 that is arranged to compress the material in an arcuate direction D3. The machine 10 has a swinging wall 24 that is movable by action of the third ram arrangement 22. The second ram arrangement 20 is moved or swung by the third ram arrangement 22 between a first position P1 (see Figure 4) in which the chamber 14 is open and able to receive a charge of material to be compressed, and a closed position P2 where, in this embodiment, the wall is in a vertical plane. In the position P1 the wall 24 may be inclined between about 45° to 75° down from the vertical at the second position P2. The third ram arrangement 22 provides the initial first stage of compression of the material.

In operation, material is deposited into the housing 12 and chamber 14 when the third ram arrangement 22 in the first position P1. The third ram arrangement 22 is then operated to move the second position P2 (shown in phantom), swinging the wall 24 into the vertical. Once in this position a swinging wall mechanical locking system (not shown) which may include locking pins mechanically locks the third ram arrangement 22 as well as locking the wall 24. Next the second ram arrangement 20 is operated compressing the material in a direction D2 into the chamber 14. A second ram arrangement locking system is operable to lock the second ram arrangement 20 at the end of its stroke. Lastly, the first ram

arrangement 16 is operated to compress the material within the chamber 14 in the direction D1 . Due to the profile of the contact face 18 the resultant block of compressed material is formed with a recessed face having a profile, complementary to that of the contact face 18.

Detailed description of compaction machine

The housing 12 has a base 26 form which extend opposed side walls 28 and 30 and opposed front and back walls 32 and 34. The swinging wall 24 is pivotally coupled with the wall 30 to swing in the direction D3 about an axis 31 that lies parallel to the direction D1 and orthogonal to the direction D2. When the third ram arrangement 22 is in the second position P2 the swinging wall 24 is substantially coplanar with the wall 30. The walls 32 and 34 are provided with curved edges 36 and 38 which follow the swinging motion of the wall 24. The chamber 14 has a horizontal bottom wall 40 that is raised above the base 26. Triangular gussets or webs 42 extends between the wall 30 and the base 26. The gussets 42 provide structural strength to the housing and act as thermal sinks.

The first ram arrangement 16 in this embodiment comprises three hydraulic cylinders 44. Each of the three cylinders 44 is pivotally connected at one end by pivot pins 45 to a stub wall 46 connected to the base 26. The cylinders 44 when in operation lie between opposed elongate side walls 48 and an overlying stiffening beam 50. The ends of the cylinders 44 distant the stub wall 46 are connected to main compression block 52. A wear block 54 that carries the contact face 18 is coupled to the compression block 52 by a hydraulic cylinder 56. The cylinder 56 can be retracted into and extended from the end of the compression block 52. The compression block 52 has a rectangular (in particular square) section matching that of the chamber 14 when the second ram arrangement has been fully extended.

Figures 7a-7e shown detail the wear block 54 and corresponding contact face 18. The wear block 54 has a rear wall 58 of a profile matching that of the compression block 52 and the chamber 14. Planar side walls 60 extend orthogonal to, and from each edge, the back wall 58. The contact face 18 which constitutes a wall of the wear block 54 opposite the back wall 58 has a non-planar and protruding profile. The contact face 18 can be considered as a compound face having a non-planar surface 62, which in this embodiment is substantially convex, and a least one or more additional surfaces 64 protruding from the non-planar surface 62. A leading edge 63 of each side wall 60 is convexly curved.

In this embodiment there are sixteen additional surfaces 64 positioned in a 4x4 matrix. Each additional surface 64 is a hemispherical surface protruding from the surface 62. Mounting lugs 66 extend from the back wall 58. The lugs 66 are provided with holes 68 for receiving a coupling pin (not shown) which demountably connects the wear block 52 to the hydraulic cylinder 56. The hydraulic cylinder 56 can extend from and retract into the compression block 52. Due to the demountable connection of the wear block 54 by the lugs 66 and locking pin, the wear block 54 can be easily replaced when worn or, to provide the compressed block of material with a face of a different configuration.

The second ram arrangement 20 comprises three hydraulic cylinders 72 which are mounted on a plate 74 attached to the swinging wall 24. The cylinders 72 have respective piston rods 76 that extend through the plate 74 and are connected to a rectangular press plate 78.

The third ram arrangement 22 is comprises two hydraulic cylinders 80 which are pivotally connected at each end between the base 26 and the swinging wall 24. Extension and retraction of the hydraulic cylinders 80 swings the wall 24 between the first (open) position P1 and the second (closed) position P2.

When the wall 24 is in the open position P1 material is dumped into the chamber 14 which is defined by various walls and components of the machine 10 including walls 24, 28, 30, 32, 34, and 40. The chamber 14 is dynamic in size and shape during the compression process. In an initial filling stage of the machine 10 the chamber 14 is at its maximum volume, example about 40 m ³ . In a final stage of compression the chamber 14 has a substantially cubic shape of a volume of about 1 m ³ . In this example machine 10 provides a compression ratio of about 40:1. It is to be understood however that in other embodiments and depending on the nature of the material to be compressed, the compression ratio may vary and for example could: range between about 15:1 to 70:1 ; or be about 15:1 or more; or be about 30:1 or more; or be about 40:1 or more.

An ejection system 84 is provided for ejecting the compressed block from the chamber 14. Ejection system 84 includes an ejection block 86 and an ejection hydraulic cylinder 88. The ejection block 86 is translated by the hydraulic cylinder 88 to move in a direction orthogonal to the direction of travel D1 of the first ram arrangement. With reference to Figure 2 the ejection block 86 slides beneath a strengthening wall 90 that extends across an end of the chamber 14 and a further parallel strengthening wall 92. Walls 94 and 96 extend orthogonal to the walls 90 and 92. Openings are formed beneath the walls 90, 92, 94 and 96.

A block of compressed material can be ejected by the ejection system down a ramp 98 in the direction of extension of the hydraulic cylinders 88. Alternately, a block of compressed material can be ejected by action of the hydraulic cylinder 56 in the direction D1 down a ramp 100. The ramps 98, 100 may lead to conveyors for transporting the blocks to a waste management facility. Alternately mechanical device such as a crane or gantry may be used to transfer the blocks from a ramp 98, 100 to a waste management facility or other location or facility.

The ejection block 86 can be extended by the cylinder 88 to a position where it is adjacent the wall 96. In this position the ejection block 86 effectively closes or forms a back wall of the chamber 14. Thus, when the first ram arrangement 16 is operated to compress the material materials compressed against the side face of the ejection block 86. The compressed block of material can be ejected down either the ramp 98 or the ramp 100.

To eject the compressed block down the ramp 98 the cylinder 88 is retracted and the cylinder 56 extended to push the compressed block into an ejection port 104 in a region beneath the walls 90, 92, 94 and 96. The cylinder 88 is then extended forcing the ejection block 86 to move through the ejection port 104 and push the compressed block down the ramp 98.

To eject the compressed block down the ramp 100 the cylinder 88 is retracted (after compression of material by the first ram arrangement 16) and the cylinder 56 extended pushing the compressed block beneath the wall 92 and onto and down the ramp 100.

When the machine 10 is in use, in order to fill the chamber 14 with material to be

compressed or compacted initially the:

• third ram arrangement 22 is operated to swing the wall 24 to the position P1 ,

opening the containment region 82;

• cylinders 72 of the second ram arrangement 20 are in the retract position so that the press plate 78 lies adjacent the wall 74;

• cylinders 40 of the first ram arrangement 16 are retracted as is the cylinder 56 so that the wear block 54 lies beneath a wall 106 adjacent a front end of the chamber 14; and

• ejection block 86 lies across and forms a rear end wall of the chamber 14.

Material is now dumped into the chamber 14 typically by a conveyor belt (described in greater detail later). Sensors detect when the containment area 82 is full or reaches a prescribed level. In one example the chamber 14, when in its maximum volume

configuration, may hold about 40m ³ of material. The third ram arrangement 22 is now operated to extend the cylinders 80 swinging the wall 24 in the direction D3 to the closed (vertical) position P2 in alignment with the wall 30. This produces a first stage or degree of compression of the material. The wall 24 is locked in place via pins and mechanical lockouts on the hydraulic swing rams of the swinging wall mechanical locking system. This gives structural integrity to the top two thirds of the chamber 14. It should be appreciated that the configuration of the chamber 14 has now changed and it is substantially rectangular, and its volume has been reduced in comparison to its maximum volume configuration when material is being dumped into the chamber 14.

In the next (second) stage of compression, the second ram arrangement 20 is operated extending the cylinders 72 to push the press plate 78 in the direction D2. This stage of compression is complete when the press plate 78 has been advanced by the extension of the cylinders 72 to a location L1 shown in Figure 4 at which the press plate 78 forms an upper horizontal wall of the chamber 14. The chamber 14 now has a different (smaller) volume than at the beginning of the second stage of compression. The press plate mechanical locking system is operated to mechanically lock the press plate 78 at the location L1 .

The final stage of compression can now start.

In the final compression stage the chamber 14 is formed by the:

• walls 28, 30, 40;

• the press plate 78 when the press plate 78 is in its lower most position, being

translated by operation of the cylinders 72 of the second ram arrangement 20;

• a face of the ejection block 86 positioned by the cylinder 88 to lie beneath the wall 90;

• contact face 18 of the wear block 54.

At the commencement of the final stage the cylinders 40 of the first ram arrangement 16 are retracted so that the contact face 18 lies substantially adjacent the wall 106 (see Figure 1 ). The first ram arrangement 16 is now operated to extend the cylinders 40, pushing the wear block 54 in the direction D2. The wear block 54 operates as a piston with the chamber 14 acting as a barrel. More particularly the side walls 60 of the wear block 54 slide in close proximity to the walls 28, 30, 40 and the press plate 78 forming a substantial seal.

During this stage the contact face 18 comprising the convex surface 62 and the

hemispherical projections 64 contact the material being compressed. The purposes and functions of the of the projections 64 in conjunction with the convex parabolic design of the wear block 54 may include:

• to increase the compressive contact surface area in comparison to a planar contact face

• to form a recessed (in essence substantially concave) face in the compressed block of material to allow for future thermal regulation and a void for gas /fluid accumulation when compressed block of material blocks are stacked in a pit and thus assist in facilitating bio gas generation;

• minimise mushrooming of the compression face 18 when large forces are applied and thus increase the life and durability of the wear block 54;

• due to the increased surface area of the convex parabolic block, increase the ability to dissipate heat and thus reduce the amount of heat conduction between the wear block 54 and the main push block 52. At the end of the third and final stage of compression the chamber 14 is now in its minimum volume configuration with the wear block 54 substantially in alignment with the wall 90 (see Figure 2).

The compressed block of material can now be ejected either down a ramp 98 or ramp 100 by operation of the ejection block 86 and corresponding cylinder 88.

The machine 10 may also include any one, or any combination of two or more, of:

• a thermal regulating system arranged to control temperature of material in the

chamber 14;

• a liquid extraction system arranged to remove liquid in the chamber; and

• a vapour extraction system to remove vapour from the chamber 14.

The thermal regulating system operates to provide the thermal protection and optimal operation of the machine 10 as well as a source of thermal energy which may be used in the thermal heating and regulation of bio digestive pits in which compressed block of organic material may be held. The thermal regulating system may include heaters incorporated in the base 26 and/or attached to one or more of the walls 28, 30, 32, 34 and 40. This may be an electrical heating system and/or one comprising one or more heat exchangers attached to one or more of the base 26 and the aforementioned walls through which a heat transfer fluid flows. The idea here is to heat the chamber 14 and more specifically the material in the chamber 14 to assist in the compaction process and the fusing of material into the block.

Additionally, when the material is organic material, heat in the block assisting in commencing biological degradation leading to the generation of methane or other bio gases. For ease of description the term“methane” as used in this specification is intended to include a reference to bio gases that are generated by the decomposition of organic material. Further, the heat assists in vaporising liquid within the chamber 14.

Depending on the nature of the material to be compacted by the machine 10, the thermal regulating system may be operable to set the temperature within the chamber 14 to between 55°C and 120°C.

As explained later with reference to the method and facility for generating methane, the thermal regulating system may include a radiator in physical contact with one or more walls of the machine 10 and a radiator located in a pit in which blocks of the compressed material are held for decomposition. A heat transfer fluid flowing between the two radiators can be used to control the temperature of the compressed material blocks within the pit and thereby assist with controlling the generation of methane. The liquid extraction system of the machine 10, may comprise a plurality of drains formed in the chamber 14 such as on the bottom wall 40. Draining liquid from the chamber 14 during compression of material assists in reducing the likelihood of forming a hydraulic lock against the action of the ram arrangements. The liquid extraction system may also include a relative negative pressure source in fluid communication with the one or more liquid drainage ports for applying a relative negative pressure to the chamber.

Two different styles of drainage ports may be incorporated in the liquid extraction system. A first type of drainage port may have a conical shape and is primarily designed for low to medium volumes of fluid as well as medium suction flow. The port may be self-cleaning via high pressure air. The port may be hydraulically opened and closed by a programmable logic controller (PLC) which is used to control the machine 10 and discussed later in this specification.

A second type of drainage port may have a flat faced piston that is designed for high to extreme pressure variants. These may also be self-cleaning via the use of high air pressure and be provided with corresponding hydraulically operated valves for opening and closing the ports controlled by the PLC.

The liquid drainage ports may be arranged along the length of the bottom surface 40. All the liquid drainage ports may be open during the second stage of compression. However, as the wear block 54 travels through the chamber 14 compressing the material in the final compression stage the PLC may be programmed to sequentially close the drainage ports as the wear block 54 passes.

Optionally an in-line separator system may be provided between the lines carrying the liquid from the chamber 14 prior to reaching a storage tank. Any separated solid material may be recycled back into machine 10 while separated oils (if any) may be sent to storage tanks that are density specific. The oil(s) may then be subjected to further processing.

A vapour extraction system may also be incorporated machine 10 and works in a manner similar to the liquid extraction system described above. The main difference is that the corresponding vapour extraction ports are on walls of the chamber 14 spaced above the bottom surface 40. The vapour extraction ports may also be open and closed by valves under the control of the PLC. A relative negative pressure source (i.e. vacuum) is plumbed to the vapour extraction ports to assist in extraction of the vapour. As the wear block 54 and corresponding contact face 18 progress through the chamber 14 in the final compression stage the PLC closes the valves as they are passed by the wear block 54. The machine 10 may be powered by a single 95 litre quad turbocharged diesel engine (or a multiple engine configuration) that can generate about 3800 Kw of power at up to about 24000nm of torque. The engine may drive four 750cc displacement hydraulic pumps with 2 or more hydraulic accumulators that working conjunction with pilot control pumps.

The machine 10 may be controlled by a PLC (programmable logic controller) loaded with or having access to a plurality of programs depending on the type of material be compressed. The PLC governs and regulates the speed and pressures of the hydraulic cylinders 40, 72, 80, 88 and the associated ram arrangements as well the speed and load control of the engine/s and other systems incorporated in the machine including the thermal regulating system, liquid extraction system, and vapour extraction system described above.

The hydraulics of the machine 10 may incorporate one or more accumulators each of which comprise a tank provided with a volume of hydraulic fluid separated by a floating piston from a volume of a compressed gas such as nitrogen or air. The compressed gas provides a degree of resilience to the application of hydraulic pressure by the ram arrangements to reduce shock. The machine 10 includes a plurality of sensors that are linked to the PLC, these include but are not limited to sensors which determine the amount of material fed into the chamber 14, the level of material within the chamber 14, the pressure and speed of travel of the cylinders incorporated in the ram arrangements 16, 20 and 22, pressure within the chamber 14, temperature within the chamber 14 and level of vacuum applied to the liquid and vapour ports.

Once the PLC determines via its associated sensors that the volume of material within the chamber 14 is at a preset level (for example 40 m ³ ) the PLC starts the first stage of compression, activating the third ram arrangement 22 and in particular the cylinders 80 to extend thereby swinging the wall 24 from the position P1 to the position P2. Once the swing wall 24 is in the vertical position P2 the swing wall mechanical locking system is activated resulting in locking pins locking the wall 24 in place. At the same time the hydraulic cylinders 80 are mechanically locked and hydraulic lock outs are initiated by the PLC.

In the second stage the hydraulic cylinders 72 of the second ram arrangement 20 are energised and the material is pushed down at a pre-programmed speed. This is when the accumulators may absorb or cushion any shock that may arise depending on the type of material being compressed. The PLC controls the rate and the speed of the stroke, as the pressure builds the PLC will automatically speed up the engine/s as well as increase the flow/pressure from the hydraulic pumps thus increasing the pressure in the cylinders 72 while still maintaining the vertical downforce and speed. The PLC monitors the flow of hydraulic oil and proximity sensors, to determine when the press plate 78 has reached its end position L1 . At this time the PLC activates the press plate mechanical locking system to mechanically lock the press plate 78 at the location L1 and lock out the hydraulic cylinders 72.

The PLC now starts the final compression stage. The PLC acts to switch the engine/s into high gear to provide maximum operating power for the hydraulic system systems and devices in the machine 10 including the accumulators. The relative negative pressure source (i.e. vacuum) associated with the liquid and gas extraction systems may now be operated to provide a relative negative pressure within the chamber 14 of between 10psi and 100 psi depending on the type and viscous nature of the material.

The hydraulic forces applied in the final (third) compression stage coupled with the negative pressure within the chamber 14 applied via the ports of the liquid and vapour extraction systems may create a negative pressure which reduces the volume of, if not completely removes, liquid that could create hydraulic compression issues. The valves associated with the liquid and vapour extraction ports are positioned strategically along a longitudinal axis of the chamber 14. At the beginning of the compression stroke of the final stage, all the valves and thus the ports are open, and the associate negative pressure is applied to the entire volume of the chamber 14 which at this time is at its maximum for the third stage.

As the cylinders 40 extend, the wear block 54 progressively travels over and past the suction ports, which are then shut via their corresponding valves. This progressive travel also of course reduces the volume of the chamber 14. However, the total negative pressure applied by the relative negative pressure source remains the same. Therefore, the total negative pressure within the chamber 14 increases exponentially which will in turn remove most if not all the fluid. The combination of the PLC increasing the speed of the engine(s) and subsequent rapid build up of hydraulic pressure in the cylinders 40, together with the increasing negative pressure within the chamber 14, may result in a block that is highly compacted as well mostly desiccated of liquid. The pressure that is applied in the final push in conjunction with the kinetic energy of the wear block 54 with a maximum volume of hydraulic fluid being provided to the cylinders 40 of the first ram arrangement 16 from the hydraulic motors may facilitate a sudden build-up of pressure, for example up to 5000 psi to all three cylinders 40. This in conjunction with the configuration of the contact face 18 may magnify the compressive forces and as such the final compression stage may be explosive in nature that may result in a compression factor of 40:1 to 70:1 or more. This magnification occurs while the full pressure of the ram arrangement 16 is transferred via the additional surfaces 66 only, due to the reduced surface area in comparison to the entire surface area of the contact face 18.

The kinetic energy imparted into the material being compressed by the wear block 54 is in part converted to thermal energy within the material that may also assist: in fusing of the material together to form a solid block; plasticising or at least softening the material being compressed; and creating heat that is retained within the block after ejection which, for organic material may assist in initiating or promoting the decomposition and generation of methane.

The PLC may be programmed to detect the final size of the compressed block and check this against a predetermined or preset size, for example about 1 m ³ . If compressed block is sensed as being smaller than the preset size the PLC may be programmed to automatically retract the hydraulic cylinders 40 and thus the compression block 52 and wear block 54, as well as simultaneously unlocking mechanical swinging wall and press plate locks and associated hydraulic interlocks. This allows for all the ram arrangements and corresponding hydraulic cylinders to be retracted into their original start position. The PLC calculates the volume of material to be deposited into machine so as at the end of a second cycle the block will be closer to or within a pre-programmed tolerance of the preset size.

In its next cycle of machine 10 can be manually or automatically changed with material so that when added to the initial compressed block is likely to result in a block being smaller than or within the prescribed tolerance of the preset size. This cycle can continue until the block is within the prescribed tolerance. Once the block has been compressed and is within the tolerance the extraction system 84 is operated and the block is pushed out the ejection port.

Figure 8 depicts an embodiment of the disclosed machine 10 incorporated in a waste processing centre 1 10. The processing centre 1 10 comprises a shredder 1 12 into which waste material 1 14 is dumped. The material travels along the conveyor system 1 15 through various sorting stages. The sorting stages may include a ferrous metal removal stage 1 16 a nonferrous metal removal stage 1 18, a plastics removal stage 120, and a glass removal stage 122. The remaining material may be largely organic in nature and is passed through a grinder 124 and dumped by the conveyor system 1 15 into a bin 126. Optionally a trammel may be placed as a first processing station along the conveyor system 1 15. The material which is now in a particulate form is carried by a conveyor belt 128 and dumped into the chamber 14 of the machine 10. The machine 10 operates as described above to compress the material from a compressed block. Liquid carried in the material 1 14 may be allowed to drain into a conduit or channel 130 running along at least a portion of the conveyor 1 15. The conduit or channel 130 may be in the form of a self-contained suction waste fluid recovery line/ pipe. In this embodiment the liquid is channelled into a receiving tank 132. The receiving tank may be in the form of a bio digestive tank. Liquid extracted from material during operation of the machine 10, including by operation of the negative pressure applied to the liquid and vapour extraction ports is directed via a channel 134 to the tank 132.

Figure 8 also shows a schematic representation of a compressed block of material resulting from the operation of the machine 10. The block 136 is of a generally rectangular block figuration but with a recessed face 138 of a profile substantially complementary to that of the contact face 18 of the wear block 54.

Figure 9a and 9b show a further representation of the compressed block of material ejected from the machine 10. Figure 9a shows the generally rectangular prism figuration of the block 136 with its recessed face 138. As result of the recessed face the block 136 has four concavely curved edges 140 about the face 138. A matrix of dimples 142 is also shown in the face 138 resulting from the action of the hemispherical protrusions 64 on the contact face 18.

Figure 9b shows the formation of a cavity or void 144 when two blocks 136 are stacked so that their recessed faces 138 face each other. When the blocks are stacked in this manner on a horizontal plane the cavities or voids 144 form multiple vertical and horizontal channels.

Figure 10 is a representation of one embodiment of the disclosed waste management facility 200. (As explained later the waste management facility 200, may be equally be considered to be an energy production facility.) The facility 200 is arranged to store waste material and produce methane from that waste material. The facility 200 is well suited to using

compressed blocks of waste material 136 produced by embodiments of the machine 10. Flowever, embodiments of the facility 200 can also be used with waste material which is not compacted by embodiments of the disclosed machine 10. The waste management facility 200 may also be considered as an energy generation system of virtue of its ability to cyclically produce biogases such as methane as an energy source.

The facility 200 comprises a pit or ravine 202 which is lined with a liquid impervious material such as concrete, which in turn may be lined with or sealed by a further liquid and gas impervious material. This forms a waterproof containment system, preventing seepage of liquids into the surrounding soil or water table. The pit 202 includes a base 204 having a plurality of channels 206 which interconnect to form a liquid collection system for directing liquid seeping from the blocks 136 into a collection tank 208. The base 204 may be inclined in a manner to allow gravity feed of the liquid into the collection tank 208. Liquid from the tank 208 can be pumped to a plant 210 for processing such as oil separation and particle separation.

The blocks 136 are stacked in the pit 200 in a manner so that the recessed/concave face 138 of one block faces the concave face 138 of an adjacent block. This creates a plurality of cavities 144 in substantial vertical alignment. The aligned cavities 144 on the top and bottom horizontal sides of the stacked blocks 136 form multiple vertical channels 212. Aligned cavities 144 on the vertical sides of the stacked blocks 136 form multiple horizontal channels 214 (represented in Figure 9b).

A false perforated raised floor may be installed over the base 204 and on which the blocks 136 are stacked. In one example the floor may be between 100-250 mm above the base 204. This allows liquid seeping from the blocks 136 to flow through the perforations into the underlying channels 206.

A manifold system or other arrangement of gas pipes 216 may be used to collect methane and other gases produced by the decaying material in the blocks 136 which in turn can be fed to a power generation system 218 for generating electricity that may be fed to the grid. In one embodiment the manifold system or arrangement of gas pipes 216 that may comprise a plurality of conduits or spears 220 provided with a plurality of holes for enabling gases produced by the material and entering the cavities 144 to flow to through the manifold system 216 to a power station 218 at a remote location. The conduits 220 are located within the cavities 144 and corresponding vertical channels 212 and interconnected with feeder conduits 222 in the manifold system 216.

A roof or cover 224 is placed over the stacked block 136 to assist in retaining heat within the pit 202 which in turn accelerates decomposition of the organic material; and also minimises the spread of odour from the decaying material. The roof 224 may be a removable roof. S. However, in other variations the roof 224 may have a different construction. For example, roof 224 may be a solid structure made of an air tight/ non-permeable /chemical resistant material, (such as a plastics material). The roof may have a domed shape. In this example the roof may then be lifted off and placed over stacked blocks 136 using a machine such as a gantry. One or more pressure relief valves may be incorporated into the roof.

Chemical/gas impervious seals may be provided on the roof 224. The roof 224 can be tied down or otherwise physically held over a stack of the blocks 136. Clamps or other arrangements may be used to ensure and maintain a leak proof seal. Indeed, this arrangement may also be used to apply a degree of compression when the pit is initially fully stacked with blocks 136. The roof may be thermally insulated to minimise heat transfer there through. Additionally, when the roof 224 is made of a non permeable material naturally it also prevents water from rain or melting snow to enter the pit.

Other variations of the disclosed method and system are possible. These includes for example stacking the blocks 136 in different juxtaposition which still form cavities between the blocks 136 through which the conduits 144 of a manifold system can pass. For example, while in Figures 9a and 10 the concave faces 138 of adjacent blocks 136 directly face each other this is not strictly necessary. In an alternate configuration the concave face 138 of one block can directly face and abut a planar face of adjacent block 136. This will still create a cavity between adjacent blocks which can be vertically aligned to form vertical and horizontal channels 212, 214. In an extreme example the blocks can be randomly stacked, and a manifold system provided with or without conduits 220 driven into or located between blocks 136 for collecting gases.

Figure 1 1 depicts a pit 202a in an alternate embodiment of the facility 200a. The facility 200a has a same general functionality and features of the facility 200, the substantive difference being in the arrangement or structure of the pit 202a and the manifold/arrangement of gas pipes.

The pit 202a is segmented into a plurality of pods 230. Each pod 230 is in the general form of a rectangular container having a liquid and gas impervious surface. For example, each may be formed of concrete and lined with a gas and liquid impervious material. Each of the pods 230 is also provided with a false floor as described above in relation to the facility 200 in Figure 10. The pods 230 are aligned in rows and have a common service/recovery pit 232 running along one side.

The compacted blocks 136 of material are stacked in each of the pits 202a in a similar manner as described above in relation to the facility 200. In addition, each pit 202a has liquid and recovery/collection channels conduits and systems as described above in relation to the facility 200. Flowever, in the facility 200a, instead of the manifold system/arrangement of gas pipes having pipes that extend vertically like the conduits 220 in the facility 200, the manifold system/arrangement of gas pipes is in the form of a horizontal planar network of gas pipes beneath the false floor but raised above the base. Notwithstanding that methane and other biogases are lighter than air, by the application of a relative negative pressure or vacuum the gases may be extracted through the manifold system for delivery to a remote location. To this end the facility 200 may be provided with a pressure regulation system to control gas pressure within the sealed pits/pods. As will be understood by those skilled in the art the decomposition of material will result in the generation of gases which will provide a positive pressure within the sealed pits/pods. In order to maintain a neutral or ambient pressure within the pit/pods the relative negative pressure system is operated reduce internal gas pressure. This also has the effect of drawing the generator gases from the pits/pods.

The decomposition of organic material produces a large quantity of biogas which may have caused comprise different types of gases to for example, but not limited to: methane, hydrogen, and carbon dioxide. The gases have different relative densities and therefore may reside in different levels of the pits/pods. The manifold system 216, may for example include a set of pipes or conduits near a top of the pit/pod for receiving the relatively light gases, such as hydrogen and a separate set of pipes or conduits near the bottom of the pit/pod, for example beneath the false floor for collecting the relatively heavier gases such as methane.

The facility 200 may also incorporate a pH regulating system for regulating the pH of material within a pit/pod. The system may operate to maintain the pH and a substantially neutral level. This may be achieved by providing one or more pH sensors within each pit/pod, monitoring the pH levels and when necessary adding an alkaline or acid to return the pH to a neutral range such as 7±0.3.

The facility 200 may also include a system for controlling levels of bacteria with the pits/pods for decomposing the material to generate the biogases. The system may operate by obtaining a measure of the amount of bacteria within they pit/pod, comparing that with an optimum level to achieve decomposition of the prescribed rate, and at least when the measured level is below the optimum level, dosing the pit/pod with further bacteria.

As a result of this arrangement of gas pipes it is possible to further modify the facility 200a by including a constant pressure mechanism if desired to maintain a degree of compression on the material within a pit 202a. This can be achieved for example by placing a plate across the top of a pit 202a when initially filled with stacked compressed blocks of material, and prior to fitting the roof 224. The plate lies on top of the compressed blocks and applies by virtue of its own weight a degree of pressure on the material. The plate is free to slide in a vertical direction as the material decomposes. Sensors in the pit 202a can detect the position of the plate and thereby give an indication of the rate of decay of material within the pits 202a. The plate may be made from metal. If desired stabilisers may be attached to the plate to ensure that it remains substantially horizontal as it slides down the inside walls of a pit 202a. Alternately or additionally the plate may be attached to a pulldown system, such as an arrangement of pulleys or hydraulic rams to allow a variation of the downward pressure applied by the plate. In a variation to the above, the roof 224 may be arranged to slide in a downward direction while keeping a seal against the inside walls of a pit 202a to achieve the same effect of applying pressure to the underlying material.

Figure 1 1 depicts a gantry 232 that travels along the row of pods 230 and is used for stacking each pod with the compressed blocks of material 136 as well as handling (i.e. lifting, lowering, or otherwise moving) the roof 224 of a pod 230, and plate if used.

Instead of the conduits 220 described in the facility 200 of Figure 10, the facility 200a can be provided with a network of gas collection pipes that extend across the width of each pod 230. These pipes may be located beneath the false floor in each pod 230 but above the base of each pod, for example by 20mm so as to not pick up liquid seeping from the blocks of material 136 through the perforations and the false floor. The gas collection pipes may extend through the walls of adjacent pods 230 so that for example the methane/biogas produced by an entire row of pods 230 may be fed by a common line to a storage facility or powerplant.

In both the facilities 200 and 200a small negative pressure for example 1 -2 psi may be applied to each pit 202, 202a (and thus for the embodiment in Figure 1 1 each of the pods 230) to assist in the extraction of the methane.

In both the facilities 200 and 200a, although perhaps more effectively applied in the facility 200a, a heat exchanger system may be incorporated in each of the pits to regulate the temperature of the material. This may include heating or cooling of the material to provide optimum conditions for the generation of methane. The heating and cooling system may include a network of pipes through which a heat exchanger fluid can flow. This fluid may also flow through a heat exchanger/radiator formed on or otherwise associated with the machine 10. In this way heat can be exchange between the machine 10 and the material within the pits 202/202a. The heat exchanger system may be arranged to maintain temperature within a pit 200/200a in the range of about 28°C to 60°C, including the range of about 32°C to 45°C The heat exchanger system within each of the pits may also include an independent water cooling arrangement such as either a network of pipes through which water flows, or indeed a plurality of spray nozzles for spraying water into the pits for cooling purposes, or extinguishing fires that start due to the heat generated by the decomposing material.

The facility 200 may include a gas purification or decontamination system for example for removing sulphur -containing gases. This purification/decontamination may be incorporated within the manifold system including for example the spears 220, and thus be achieved within the pit/pods. Alternately the gases extracted from the pits/pods can be sent to decontamination/purification vessels or systems to remove contaminants prior to the gases being used for example for generation of power.

Any material remaining within a pit/pod after decomposition and maximum extraction of biogases may be collected and used as fertiliser. It should be understood that the pits/pods can then be reused by re-stacking with compressed blocks of material to start a next cycle of methane/bio gas generation. In this way the waste management facility 200 may be seen more as an energy generation facility where the pits/pods are continually refuelled with the compressed material for the generation of biogases. Indeed, it is envisaged that the generation of biogas as a fuel in commercially viable amounts may be a key driver or primary purpose for the use and implementation of embodiments of the disclosure. In such instances the issue of waste management is a beneficial by-product of the disclosed energy generation facility.

Now that embodiments have been described it should be appreciated that the machine, methods, systems and facilities may be embodied in many other forms.

For example, in the machine 10, the wear block 54 is shown with a protruding contact face 18 which has a smoothly curved convex surface with a plurality of hemispherical protrusions. However, the contact face 18 may have different configurations including for example the contact face 18 could have a chequerboard configuration of planar rectangular protrusions and rectangular recesses, or formed with castellated sides as shown for example in the block 136a shown in Fig 9c. Here one face of the block 136a has a rectangular protrusion 137 at each corner. Also, while only one face is described as being recessed the machine 10 can be easily modified to form a second recess surface on an opposing face. This can be done for example by providing a die at an opposite end of the chamber 14 from which the wear block 54 enters. In this event the machine would also require a rudimentary or very simple modification to enable easy ejection of the compressed block.

The above examples are made largely with reference to the compaction of organic material. However, the machine 10 is not limited to operation with organic materials or household waste, and may be used in relation to all materials and mixtures of materials such as but not limited to: coal, hay, metals, plastics materials, flock etc. The machine 10 may also be used to compact waste building materials however such waste cannot be used to generate any biogases, or at least not in commercially viable volumes.

It should also be recognised that embodiments of the waste storage and methane production facility 200/200a, are not limited in use to only compressed blocks of material provided with a recessed face. The facility 200/200a is equally operable with compressed blocks without recessed faces or indeed with non-compressed organic material. When used with such materials the facility 200/200a remains operable to: harvest methane and other biogases; separately collect and process liquid emanating from the material; and of course, handle the material in the described liquid and gas impervious pits maintaining environmental integrity.

Embodiments of the present disclosure are well suited to the rapid and accelerated generation of methane and other biogases specifically for the purposes of energy production. Indeed, embodiments of the present invention amplify the production of methane over traditional waste management systems. This amplification may be assisted by one or more of the following aspects taken individually:

• initial sorting of rubbish with a view to specifically exclude non organic materials from the final material dumped into the machine 10;

• the degree of compression provided by the machine 10 which assists in maximising the density of the compressed block;

• heat transfer to the material in the machine 10 by both the heating system and also conversion of kinetic energy from the first ram arrangement 16 to the material being compressed;

• the formation of recesses in the compressed blocks which when abutted against another block form a plurality of chambers or voids through which methane and other biogases can flow;

• the use of pits/pods for holding the compressed blocks that provide an airtight and temperature controlled environment for the decomposition of the material;

• the provision of heat exchangers to enable control of the temperature within a

pit/pod; and

• application of a relative negative pressure to the pit/pods to assist in extraction of gases and the formation of an anaerobic environment.

From initial tests conducted on behalf of the Applicant it is believed that embodiments of the disclosed machine when incorporated with the disclosed waste management facility may result in the generation of methane and other biogases 10 to 30 times faster than via the use of traditional landfill and gas harvesting techniques.

Any discussion of the background art throughout this specification should in no way be considered as an admission that such background art is prior art, nor that such background art is widely known or forms part of the common general knowledge in the field in Australia or worldwide.

In the claims which follow and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word“comprise” and variations such as“comprises” or“comprising” are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features of the embodiments as disclosed herein.