FIELD OF INVENTION The present invention relates to an apparatus for

producing compost.

BACKGROUND OF THE INVENTION Composters are used to convert waste material into

compost, which is commonly used for agriculture.

Typically, composters allow recycling of waste material generated by, for example, households and schools, into compost for enriching soil for gardens or vegetable patches. This reduces landfill waste and expenditure on synthetic fertilizers .

A composter is typically made of non-recyclable material and is usually expensive to replace. As such, the

composter has to be maintained and cleaned periodically to prolong its lifespan. This makes owning a composter inconvenient as repairing and cleaning the composter are usually time-consuming and expensive. Additionally, one method for forming compost involves the use of decomposers (also known as saprotrophs) , such as earthworms, or other organisms, for example, insects, fungi or bacteria to break down the waste material in the composter. However, the efficiency of the decomposition is depending on the oxygen concentration in the waste

material. Typically, waste material is often compacted when placed in a composter, which creates uneven oxygen distribution within the waste material. This leads to a concentration of the decomposers in the oxygen-rich regions of the waste material which, in turn, results in an uneven rate of decomposition. As a consequence, the waste material has to be turned to ensure even compost formation .

It is desirable to provide a composter that aerates waste material to enhance compost formation without the need to regularly turn the waste material. Preferably, the

composter is recyclable.

SUMMARY OF THE INVENTION The present invention provides a composter for producing compost from household and other types of waste material, the composter being adapted to stand upright and includes a side wall that defines a compost-forming space, the side wall including at least one region having an outer panel and an inner panel having a gap therebetween for air flow from outside the composter and through the gap into the compost forming space.

The present invention also provides a composter for producing compost from household and other types of waste material, the composter being adapted to stand upright and includes a side wall that defines a compost-forming space, and at least one divider for partitioning the compost- forming space into at least two vertically spaced regions to control moisture and/or heat distribution between the spaced regions .

An advantage of the present invention is that the speed of compost formation is accelerated compared to compost formation without using the presently claimed composter.

In this specification, the phrase "compostable material" includes waste material obtained from facilities such as schools or farms .

In one embodiment, the side wall may comprise an outer panel and an inner panel separated by a gap for air flow from outside the composter and through the gap into the compost forming space.

In another embodiment, the inner and outer panels may be provided on an inner surface of the side wall .

Each panel may comprise more than one section or segment.

The inner panel may have a plurality of openings and/or channels to allow air flow from the gap into the compost- forming space.

The openings in the inner panel allow aeration of

compostable material in the compost-forming space. This increases the rate of compost formation by providing a hospitable environment for decomposers to decompose the compostable material.

Typically, the openings are spaced about the inner panel to allow the compostable material in the compost-forming space to be substantially evenly aerated. This allows decomposers to be evenly distributed within the

compostable material, which in turn, increases compost formation. The openings may also allow drainage of fluids generated during the decomposition.

The outer panel may include one or more openings and/or channels to allow air flow from the external environment into the gap.

The openings and/or channels in the outer panel may also allow moisture or gas formed during the decomposition to be released more quickly into the atmosphere . The openings in the outer panels may align with similar openings on an adjacent composter to form interconnecting channels . The channels may allow decomposers to travel between composters, for example, to facilitate the

migration of earthworms from a composter that is exhausted of compostable material to a composter having compostable material .

The side walls may also include internal channels to allow air flow along and within the length of the side walls .

The composter may include a divider for partitioning the compost-forming space into at least two spaced regions to reduce compaction of the compostable material and increase air flow through the compost-forming space. The spaced regions may be vertically-arranged (e.g. levels) or horizontally arranged.

The divider may control, such as by hindering, moisture and/or a heat distribution between the spaced regions. This retains moisture and/or heat within a spaced region to reduce the likelihood of the compost dehydrating or cooling excessively. Retaining moisture within the compost may also reduce odour release from the compost.

The ability to retain moisture within a spaced region may also reduce the likelihood of the compost overheating during the decomposition. For example, retaining moisture within the spaced region maintains the compostable

material at a temperature ranging from 45-55°C. In turn, this reduces the likelihood of thermophilic bacteria acting on the compostable material, which causes the compostable material to overheat to about 70-80 °C. The elevated temperature may cause decomposers such as

earthworms to perish.

Suitably, the divider may maintain the compostable

material at temperatures ranging from 45-55°C during compost formation. The divider may extend from the side wall of the

composter.

The divider may be substantially planar and be of similar configuration to the cross section of the compost-forming space. In an embodiment, the divider may comprise sheet material .

The formation of spaced regions may distribute the weight of the compostable material in the compost-forming space between the spaced regions and reduces the likelihood of the compostable material being compacted. For example, when a single divider is used to create two vertically- arranged spaced regions , the total weight of the

compostable material in the composter may be distributed between the divider and the base of the compost-forming space. This improves aeration of the compostable material by reducing the likelihood of the compostable material compressing under its own weight which consequently drives oxygen from the compostable material.

The aeration of the compostable material reduces the likelihood of decomposers concentrating in oxygen-rich regions of the compostable material. For example, without the use of dividers, the compostable material nearer the base of the compost-forming space would be compacted under its own weight. This results in decomposers concentrating in the oxygen-richer compostable material located higher up in the composter.

The divider may include internal channels extending substantially parallel to a major surface of the divider to allow air flow along and/or within the divider. The divider may alternately or additionally include openings extending between major surfaces of the divider to allow air flow through the divider. The openings may also allow decomposers to travel between the spaced regions . The internal channels of the divider may extend in more than one direction to allow cross-air flow. The divider may include longitudinal internal channels to allow air flow along the length of the divider. The divider may include lateral internal channels that allow air flow along the breadth of the divider. The

longitudinal and lateral channels may be interconnected to allow cross air flow.

The channels within the side walls and dividers of the composter provide increased air flow from the external environment into the composter.

The side wall and/or divider may comprise a corrugated sheet material to form the channels that provide air flow through the compost-forming space. The corrugated sheet material may comprise corrugated cardboard or corrugated plastic (also known as corflute) .

An increased air flow through the composter aerates compostable material in the compost-forming space and increases compost formation. Typically, worms, such as earthworms, are used for forming compost. An increased air flow through the composter increases the amount of oxygen- rich areas within the compost-forming space in which the worms can reside, which in turn, increases compost

formation .

The openings and the channels in the side wall/s and divider/s may facilitate gaseous exchange. For example, the openings and channels may allow gases , such as methane and carbon dioxide, formed during the decomposition process to escape from the composter, and allow air from the atmosphere to enter the composter. The divider may be made of at least one panel of corflute. The divider may be made of at least two corflute panels positioned such that the channels of one panel are

transverse to the channels of another panel . The channels of a panel may be interconnected to the channels of another panel .

The channels located in the divider and the side walls allow air flow along and across the compost-forming space.

The composter may be made of a degradable material.

Preferably, the composter may be made of a biodegradable material . The composter may be made from cellulosic material to provide a recyclable composter. Using a cellulosic

material also allows the composter to provide a disposable composter. The cellulosic material may be cardboard. In this specification, the term "disposable" refers to a composter that is adapted to be replaced periodically, for example, within one year. In this respect, the composter may be adapted to degrade within a year. This is in contrast to composters that are adapted to last for a longer period of time, for example, at least one year.

A disposable composter reduces maintenance cost as the composter can be disposed when damaged or soiled instead of being repaired or cleaned.

The composter and/or divider may be coated with a water- resistant layer. The water resistant layer may prolong the structural integrity of the composter by slowing

degradation of the composter by water. The water-resistant layer may be a polymer coating. The composter may further include an aerator for aerating the compostable material. The aerator may include internal channels that allow air flow along a major surface of the aerator. The aerator may include internal channels that extend in more than one direction to allow cross air flow along a major surface of the aerator. The aerator may include openings that allow air flow through the aerator.

In an embodiment, the aerator may comprise a layered assembly including at least one corflute panel. In this embodiment, the at least one corflute panel may include an open channel in an outer surface thereof, such that upon forming the layered assembly, an internal conduit is formed within the assembly.

The aerator may comprise at least one corflute panel mounted on a non-porous support.

The aerator may comprise two corflute panels mounted on a non-porous support. The corflute panels may be arranged to form interconnecting channels that allow debris entering the aerator to be flushed out by directing a fluid, such as water, through the aerator. The non-porous support may be made of a non-flexible material such as metal to protect the aerator against warping .

In an embodiment, the at least one region of the side wall for air flow from outside the composter and through the gap into the compost forming space may comprise an

aerator. In this embodiment, the aerator is positioned against the side wall of the composter to facilitate gaseous exchange between the atmosphere and the compost forming space. The aerator may be in fluid communication with an opening in the side wall to enable air flow from the atmosphere into the compost forming space. Suitably, one end region of the aerator is aligned with an opening on the lower part of the side wall and the other end region is positioned to be exposed to the atmosphere at an upper part of the composter. By this arrangement, air may to be drawn into the aerator from the lower part of the side wall and gases formed during the decomposition process may exit through the other end region of the aerator at the upper part of the composter. Any number of aerators can be positioned along the side wall to facilitate gaseous exchange.

The aerator may be free-floating (i.e. the aerator is not attached to the side wall of the composter) .

Alternatively, the aerator may be attachable to an inner surface of the side wall. In another embodiment, the aerator may be fixed onto a divider. The aerator may be placed within the compostable material to increase

aeration of the compostable material within the spaced region.

The composter may be open at at least one end to promote air flow. The composter may comprise at least one blank which is foldable to form the side wall .

In the embodiment where the side wall comprises an outer panel and an inner panel separated by a gap, the composter comprises at least one blank which is foldable to form the outer panel of the side wall and the inner panel of the side wall. The composter may comprise first and second blanks which are foldable to form the outer and inner panels, respectively. The outer panel may interfit with the inner panel to form a double-panelled side wall having a gap therebetween. The or a blank may be foldable to form a reinforcing rib along an end of the composter. For example, an edge of the first blank may be foldable to form a reinforcing rib along the top end of the composter when assembled.

A reinforcing rib may be located at the top edge of the composter when assembled to protect the side wall against collapse from a load placed on top of the composter. A reinforcing rib may be located at the bottom edge of the composter to protect the side wall against collapse when the base of the compost-forming space is subjected to any force, for example, when the composter is dragged along the ground.

At least one surface of the or each (e.g. the first and/or second) blank may be coated with a water-resistant layer.

The present invention also provides a kit for a composter as previously described comprising: one or more blanks being foldable to form the side wall .

The kit may comprise one or more blanks being foldable to form the outer panel of the side wall and the inner panel of the side wall, the inner panel having a plurality of openings therein .

The kit may include a packaging for containing the or both blank (s) , wherein the packaging is perforated with the outline of at least one divider such that the divider is removable from the packaging for use with the composter.

The present invention also provides an assembly of composters, each composter including a side wall that defines a compost-forming space, the side wall including at least one region having an outer panel and an inner panel having a gap therebetween for air flow from outside - li the composter and through the gap into the compost forming space, the side wall further includes at least one opening that is (are) aligned with similar opening(s) of a side wall of an adjacent composter to form passage (s) for decomposers to travel between the composters.

BRIEF DESCRIPTION OF DRAWINGS

An embodiment of the present invention is hereinafter described by way of example only, with reference to the accompanying drawings , wherein :

Figure 1 is an isometric view of a composter according to one embodiment of the present invention.

Figure 2 is a top view of a disassembled composter of Figure 1.

Figure 3 is an isometric view of a first blank of the composter of Figure 1.

Figure 4 is an isometric view of an second blank of the composter of Figure 1. Figure 5 is an isometric view of a divider for the

composter.

Figure 6 is an isometric view of a packaging for

containing the composter

Figure 7 is an isometric view of an aerator for the composter.

Figure 8 is an isometric view of another aerator for the composter. Figure 9 is a broken-out section view of a composter according to another embodiment of the present invention.

DETAILED DESCRIPTION

One embodiment of the composter as defined by the present invention is marked as 10 in Figure 1.

The composter 10 includes a side wall 12 that defines a rectangular compost-forming space 14. The side wall 12 comprises an outer panel 16 and an inner panel 18

separated by a gap 20 for air flow from outside the composter 10 and through the gap 20. The inner panel 18 has a plurality of openings 22 to allow air flow from the gap 20 into the compost-forming space 14. The openings 22 are spread about the inner panel 18 to allow compostable material in the compost-forming space to be evenly aerated. The openings 22 also allow fluids, including gases, generated during the decomposition process to escape from the compost-forming space.

The outer panel 16 includes openings 24 for increasing air flow from the external environment into the gap 20 and allows gases formed during the decomposition process to be released more quickly into the atmosphere .

The base and top of the compost-forming space 14 are open to the environment to optimise air flow and allow fluid to drain from the waste material in the composter 10. In an alternative embodiment, the base of the compost-forming space 14 is covered to allow the composter to be

transportable when filled. Dividers 30 are mounted on the inner panel 18 to partition the compost-forming space 14 into at least two vertically arranged spaced regions (i.e. levels) (Figure 5). Each panel of the side wall 12 and the divider 30 are made from corrugated cardboard coating with a water resistant layer of polypropylene to slow water-based degradation of the composter and maintain the structural integrity of the composter.

The corrugation of the panels and the divider provide internal channels 32 that extend parallel to a major surface of the panels and divider for improving air flow. The internal channels 32 on the panels provide air flow along the length of the composter 10, while the internal channels 32 on the dividers provide air flow across the length of the composter (i.e. along a major surface of the divider) .

The divider 30 further includes openings 34 that extend between major surfaces of the divider (i.e. the upward- facing and downward-facing surfaces of the divider) to allow air flow through the divider (i.e. between the levels of the composter 10) . Openings 34 also allow earthworms to travel between the spaced regions to

facilitate the distribution of earthworms throughout the compost-forming space.

The composter 10 is assembled by unpacking first blank 17 and second blank 19 from packaging box 36. Dividers 30 are cut into the packaging box 36 and can be separated from the box 36 by pushing against perforations 38 (Figure 6) .

The first blank 17 (Figure 3) is folded to form the outer panel 16 in the form of a rectangular prism. The second blank 19 (Figure 4) is folded to form the inner panel 18 also in the form of a rectangular prism. The inner panel 18 is inserted into the outer panel 16 to form a double- panelled side wall having the gap 20 therebetween (Figure 2) . The top edge 26 of the first blank 17 is foldable to form a reinforcing rib 28 locating along the top of the

composter. The reinforcing rib reduces the likelihood of the composter being crushed by a load placed on top of the composter. The reinforcing rib also holds the inner panel 18 within the composter by folding over the top edge of the inner panel . In use, the composter 10 is assembled and placed in an upright position (as shown in Figure 1) on an area for receiving compost, such as a garden bed. The composter 10 is then filled with compostable material such as waste food scraps , and earthworms . Once the material is filled to the level of divider mounts (not shown) on the inner panel 18, dividers are fastened to the mounts before more compostable material is added to the composter 10.

Additional dividers may be added to the composter in a similar manner. The dividers reduce compaction of the compostable material by distributing the weight of the material in the compost-forming space between the spaced regions, which in turn, increases air flow through the compost-forming space and reduces the amount of oxygen lost by the material by compression.

An aerator 40 (as shown in Figure 7) is added into the compostable material to further improve aeration. The aerator 40 comprises a layered assembly of three

corrugated plastic panels, in the form of corflute panels 42, 44, 46 (Figure 7) joined together. Panel 46 acts as a support for reducing warping of panels 42 and 44, and may be substituted for a non-corrugated material such as a sheet of stainless steel. Panel 44 comprises two strips of parallel corflute panels that are sandwiched between panels 42 and 46 to form an internal channel 43 extending parallel along the length of the aerator. Air travels through the channel 43 and within each of the panels (through the internal channels formed by the corrugations of the corflute panels) to improve air flow within the compostable material. Any debris trapped within the channels between the panels can be removed by directing a fluid, for example, water or air, through the channel .

Alternatively, panel 46 may comprise a number of

discontinuous pieces of corflute panels (akin to panel 42) that are staggered relative to panel 42 such that a tortuous path through the aerator is formed. This allows air flow through the aerator while reducing the likelihood of compostable material from clogging the openings of the aerator 40.

An alternative form of aerator 40 is illustrated in Figure 8. The aerator comprises two corflute panels 48 and 50 fixed to each other. Both panels 48 and 50 include an open channel along a major surface of each panel and are fixed to each other such that the open channels are aligned to form a central internal channel 52 running along the length of the aerator. An increased air flow through the compostable material increases compost formation by providing a hospitable environment for the earthworms and reduces the likelihood of the earthworms concentrating in localised oxygen-rich regions of the compostable material.

After the compost is formed, the composter is disassembled or lifted from the ground to spread the compost for use. If the base of the compost-forming space 14 is covered, the composter may be transported to a target site for receiving the compost. Depending on the degradation of the composter, the

composter can then be discarded or reassembled for further use. Typically, the dividers 40 degrade at a faster rate than the side panels 12 of the composter. Accordingly, the life of the composter can be extended by replacing the dividers and reassembling the composter for further use. The biodegradable nature of the composter also allows the composter to be used as waste material for composting. Another embodiment of the composter as defined by the present invention is marked as 100 in Figure 9.

The composter 100 includes a side wall 112 that defines a rectangular compost-forming space 114. The side wall 112 is single walled and includes mounts (not shown) for attaching an aerator 140 onto the side wall 112 and to align the lower end of the aerator 140 with opening 124.

The aerator 140 comprises an assembly of panels 50 and 48 arranged such that the internal channels 54 of panel 48 are transverse to the internal channels 56 of panel 50. Each panel includes an open channel that forms part of a central internal channel 52 when assembled to form aerator 140.

The central internal channel 52 is in fluid communication with the internal channels 56 to form cross channels that allow longitudinal and lateral air flow along through the aerator 140. These cross-channels also facilitate the escape of gases, formed in the compost forming space during the decomposition process, to the atmosphere.

An end of the aerator 140 is aligned with opening 124 of the side wall 112 to draw air into the compost forming space via opening 124. The aerator also allows gases formed during the decomposition to exit via channels 52 and 54 at the top of the composter 100. This improves gaseous exchange between the atmosphere and the compost forming space 114.

As such, the aerator 140 forms a region on the side wall 112 for air flow from outside the composter 100 and through the central channel 52 into the compost forming space 114.

Accordingly, there is provided a recyclable composter that aerates waste material to enhance compost formation without the need to regularly turn the waste material.