Food waste recirculation

Abstract

Disclosed herein is a method for producing animal feed having defined nutritional characteristics from food waste. The method includes accumulating consecutive batches of a plurality of food wastes that have been impregnated and dehydrated, each batch of each of the plurality of food wastes originating from the same one of a plurality of classifications of food waste producers and maintained separately from the other of the plurality of food wastes; independently mixing each of the accumulated batches of impregnated and dehydrated food waste to produce a plurality of homogenized ingredients for animal feed; analyzing each of the homogenized ingredients to determine one or more nutritional parameters of the ingredient; and blending two or more of the homogenized components to produce the animal feed having the specified nutritional characteristics.

Description

Technical Field

[0001] The present invention relates to processes, methods and apparatus for use in food waste recycling, and in particular for recycling food waste into high-quality animal feed. Background Art

[0002] It is reported that almost one third of the food produced for human consumption is wasted, resulting in huge economic and environmental costs. Dealing with food waste on a commercial scale has become increasingly problematic, as it is generally no longer acceptable to send all food waste to landfill. Many ingenious solutions have been proposed to the food waste problem, however few of these solutions have achieved commercial success.

[0003] In one such solution, one of the inventors made an invention involving a unique method for recycling food waste. The invention is described in International (PCT) Application No. PCT / AU2017 / 051130, the contents of which are hereby incorporated into this specification in their entirety. However, in the process of implementing the invention on a commercial scale, additional problems became apparent. Summary of the invention

[0004] The present invention generally relates to apparatus, processes and methods for recycling food waste to obtain maximum environmental and economic benefits, such as when the food waste is used to produce high-quality animal feed. As will be apparent from the disclosure below, a primary object of the present invention is to enable virtually any food waste to be recycled into a saleable product with little to no waste. The environmental benefits of the present invention are significant, both in reducing the amount of food waste sent to landfills and in enabling products such as high-quality animal feed to be produced without having to use other ingredient sources (e.g., grains and protein sources) that may be more beneficially used as human food.

[0005] In a first aspect, the present invention provides a method for producing an animal feed having specified nutritional characteristics from food waste. The method comprises: accumulating successive batches of a plurality of food wastes that have been macerated and dehydrated, each batch of each of the plurality of food wastes originating from the same category of food waste generators among a plurality of categories of food waste generators and maintained separately from other food wastes in the plurality of food wastes; independently mixing each of the accumulated batches of macerated and dehydrated food wastes to produce a plurality of homogenized components for animal feed; analyzing each of the homogenized components to determine one or more nutritional parameters of the components; and blending two or more of the homogenized components to produce the animal feed having specified nutritional characteristics.

[0006] As described in PCT / AU2017 / 051130, the inventors have discovered that certain categories of food waste can be processed to produce animal feed ingredients with relatively consistent nutritional properties. For example, food waste from a bakery, a cafe and a butcher shop can be processed separately to produce ingredients with different nutritional properties for the resulting animal feed. Such ingredients provide countless blending opportunities for producing animal feed with nutritional content that enables it to command a premium price.

[0007] The subject matter of the invention of PCT / AU2017 / 051130 has been successfully implemented, and animal feeds such as chicken feed, shrimp feed and fish feed have been produced. However, the inventors have found that there are slight variations between batches of classified food waste, even when obtained from exactly the same food waste generator. In some applications, these variations are tolerable. However, high-quality animal food products (such as chicken feed) have very strict requirements, and these variations are incompatible with such food products. It has been found that the homogenization, analysis and blending steps in the method of the present invention have provided a good solution to this problem. The method of the present invention is capable of producing animal feeds with precisely defined nutritional properties from food waste. Further, considering the diversity of food waste sources that can be utilized, the ingredients produced in the process of the present invention have nutritional parameters of corresponding diversity. Such a diverse raw material of readily available ingredients is used to produce animal feeds with virtually any given composition, providing a large number of blending opportunities. In fact, in some embodiments, animal feeds (such as chicken feeds) that meet strict standards can be produced without requiring any ingredients other than those obtained from food waste. The benefits in terms of cost and guaranteed ingredient supply are obvious.

[0008] In a second aspect, the present invention provides a method for dehydrating macerated food waste. The method comprises mixing a material having a moisture content different from the moisture content of the macerated food waste into the macerated food waste near an inlet of a dehydrator, wherein the added material and the macerated food waste are mixed so that the mixture at the inlet of the dehydrator has a defined and substantially uniform moisture content. The mixture can then be dehydrated.

[0009] In a third aspect, the present invention provides an apparatus for dehydrating macerated food waste. The apparatus comprises: a hopper, the outlet of the hopper leading to the inlet of a dehydrator; a moisture detector configured to detect the moisture content near the outlet of the hopper; a conduit through which a material having a moisture content different from the moisture content of the macerated food waste can be added to the macerated food waste near the outlet of the hopper; and a mixer for mixing the material and the macerated food waste in a manner such that the resulting mixture presented to the inlet of the dehydrator has a specified and substantially uniform moisture content.

[0010] The second and third aspects of the present invention advantageously overcome the problems associated with dehydrating macerated food waste that has a variable water content or is either too moist or (less commonly) too dry. Once fed into the dehydrator used in the inventors' experiments, the macerated food waste is rapidly broken into smaller particles. Relatively dry particles may be damaged by overheating, while relatively moist particles may not be adequately dehydrated.

[0011] However, in these aspects of the invention, blending the second (generally drier) material into the macerated food waste at a specific location in the hopper ensures that proper mixing occurs and that the material presented to the dehydrator has a relatively consistent moisture content as well as a target moisture content (e.g., 50% moisture). Thus, the dehydrator can be operated to dehydrate a substantial portion of the mixture while reducing the risk of any damage to the material. It will be appreciated that overheating can be detrimental to the nutritional content of many categories of food.

[0012] In a fourth aspect, the present invention provides a method for producing a dehydrated granular powder from macerated food waste. The method comprises dehydrating the macerated food waste to produce a dehydrated product, and then stirring the dehydrated product as it cools so as to prevent agglomeration and produce the dehydrated granular powder.

[0013] Advantageously, this aspect of the invention has been found to prevent granular particles of food waste from clumping together which can occur when some types of food waste are cooled (this has been found to be a particular problem when processing food waste streams having a relatively high fat content).

[0014] In some embodiments, the method of the fourth aspect may also include biosafety treatment. For example, the method may include biosafety treatment, which includes maintaining the dehydrated product produced in the dehydrator at a temperature of at least 100° C. for a period of at least 30 minutes. Heating to this temperature and maintaining this time will ensure that any pathogens (such as microorganisms and viruses) that may be present in the dehydrated granular powder have been killed. After treatment, the dehydrated granular powder is completely biosafe and therefore will not be a source of bacteria, viruses, fungi or any other pathogenic contaminants, any of which is undesirable in an industrial environment or may cause downstream corruption. The biosafe granular powder of the macerated and dehydrated food waste produced by this method is shelf-stable and pathogen-free, and can therefore be stored for longer periods of time without corruption issues.

[0015] In a fifth aspect, the present invention provides an infuser assembly, comprising an infuser having an inlet and an outlet, wherein the inlet is connectable to the outlet of a storage container; and wherein the infuser is movable between a plurality of storage containers.

[0016] Such an infuser assembly advantageously reduces the capital cost of industrial applications of the invention and achieves efficiencies that might not otherwise be obtained.

[0017] The following will describe additional features and advantages of various aspects of the present invention in the context of specific embodiments. However, it should be understood that such additional features may have more general applicability in the present invention than described in the context of these specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Embodiments of the present invention will be described in further detail below with reference to the following drawings, in which:

[0019] Figure 1 A schematic diagram of a method for producing animal feed from multiple classified waste streams and incorporating various embodiments of the present invention is shown. DETAILED DESCRIPTION

[0020] As stated above, the present invention is directed to a method by which animal feed can be produced from large quantities of separately collected, maintained and processed sorted food waste.

[0021] As used herein, the terms "food waste" and the like are intended to encompass a variety of food waste including, but not limited to, coffee grounds, vegetable matter, dairy products, bakery waste, meat trimmings and bones, and seafood shells (e.g., oysters, mussels, lobsters, etc.).

[0022] As used herein, the terms "food waste generator", "generator of food waste" and the like are intended to cover any establishment that regularly generates a reasonable amount of food waste. Food waste generators include, but are not limited to, restaurants, cafes, bars / clubs, nursing homes, hospitals, supermarkets, grocery stores, greengrocers, delicatessens, butchers and bakeries.

[0023] As used herein, the terms "classes of food waste," "generators of classified food waste," and the like refer to different food waste streams and sources of these wastes that will have relatively consistent compositions between successive batches due to their common sources. Classes of food waste include those described immediately above, which are generated by the respective food waste producers described in the previous paragraphs. For example, one class of food waste may be bread products (waste obtained from a bakery), and another class of food waste that is collected, maintained, and processed separately from bakery waste may be meat trimmings (obtained as waste from a butcher shop).

[0024] In its first aspect, the present invention provides a method for producing an animal feed having specified nutritional characteristics from food waste. The method comprises: accumulating successive batches of a plurality of food wastes that have been macerated and dehydrated, each batch of each of the plurality of food wastes originating from the same category of food waste generators of a plurality of categories of food waste generators and maintained separate from other food wastes of the plurality of food wastes; independently mixing each of the accumulated batches of macerated and dehydrated food wastes to produce a plurality of homogenized components for animal feed; analyzing each of the homogenized components to determine one or more nutritional parameters of the components; and blending two or more of the homogenized components to produce the animal feed having specified nutritional characteristics.

[0025] In the present invention, food waste is classified based on its source. The nutritional properties of food waste collected from the producers of different types of food waste are expected to have considerable differences. For example, the food waste produced by bakers is unlikely to have the same high protein content as the food waste produced by butchers. However, it has been found that the categories of food waste collected only from bakeries (etc.) and processed independently of other categories of food waste make processed food waste have significantly consistent nutritional properties between batches. Similarly, food waste collected from sources such as restaurants / cafes, greengrocers or butchers has relatively consistent nutritional properties between batches. Therefore, each of these categories of food waste can be combined (that is, with the same category of food waste of other batches---for example, food waste collected from the same source after one day) and processed independently of other categories of food waste, so as to produce a variety of ingredients with different nutritional properties. These ingredients provide a variety of blending opportunities, so that animal feed with customized nutritional content can be produced.

[0026] In contrast, in many prior art processes, food wastes are mixed together and, when processed, result in animal feeds having non-specific and highly batch-variable nutritional content. Such animal feeds, while providing nutrition to the animals, do not command a high price at all.

[0027] As described above, the inventors have recently discovered that there are slight variations between batches of classified food waste, even when obtained from exactly the same food waste producer. Although such variations may be tolerable in some applications, high-quality animal food products (e.g., chicken feed) have very strict requirements, and variations in nutritional content are completely unacceptable. The homogenization, analysis, and blending steps of the methods described herein allow animal feeds with precisely defined nutritional properties to be produced from food waste. Such products can fetch high prices.

[0028] Advantageously, some embodiments of the methods of the present invention may also result in zero waste, where all incoming food waste ultimately becomes a final saleable product, such as animal feed.

[0029] The method of the present invention comprises accumulating successive batches of a plurality of classified food wastes that have been macerated and dehydrated, each batch of each of the plurality of classified food wastes originating from the same classified food waste generator of a plurality of classified food waste generators and maintained separate from other classified food wastes. The classified food waste generators may be independently selected, for example, from restaurants, cafes, supermarkets, grocery stores, greengrocers, delicatessens, butchers, bakeries, etc.

[0030] Apparatus, methods and systems for collecting and separately maintaining multiple categories of food waste are described in PCT / AU2017 / 051130 and are not repeated here. Macerators and dehydrators for macerating and dehydrating products such as food waste are known and specific examples of such are described in the context of preferred embodiments of the present invention.

[0031] The method also includes independently mixing each of the accumulated batches of macerated and dehydrated food waste to produce a plurality of homogenized components for animal feed.

[0032] The accumulated batches of macerated and dehydrated food waste may be mixed at any convenient time. For example, in some embodiments, the accumulated batches may be mixed once the amount of the accumulated batches reaches a predetermined threshold. Alternatively, if the animal feed to be produced requires ingredients having nutritional properties that may be provided by a particular class of food waste, any accumulated batches of said food waste may be processed immediately to produce the corresponding homogenized ingredients (although perhaps in less amounts than in the previous embodiments). Mixing may be performed in any suitable apparatus.

[0033] Given that the macerated and dehydrated food waste is typically in the form of a granular powder, pneumatic conveying can be conveniently used to transfer material between storage containers for the macerated and dehydrated food waste and storage containers for the homogenized component, and vice versa. In fact, pneumatic conveying can be conveniently used to transfer granular powders in any "dry" area of ​​the entire process.

[0034] The method further comprises analyzing each of the homogenized ingredients to determine one or more nutritional parameters of the ingredients. Any suitable equipment may be used for such analysis, wherein a sample of a specified weight or volume (e.g., 1 L) of the homogenized ingredients is removed from the bulk material and taken to a laboratory (e.g., an on-site laboratory) for testing. Examples of nutritional parameters that may be determined include: protein content, fat content, amino acid content, and specific gravity.

[0035] The method also includes blending two or more of the homogenized ingredients to produce an animal feed having specified nutritional properties.

[0036] Typically, blending involves determining the relative amounts of each of the homogenized ingredients required to produce the animal feed having the specified nutritional characteristics. An analysis of the nutritional properties of each ingredient can be entered into a computer system, for example, along with the desired resulting nutritional content of the animal feed. The computer system can then process this information and provide the precise proportions of each ingredient required to produce the animal feed (usually based on volume).

[0037] In some embodiments, it may be necessary to add minor ingredients to the blended homogenized ingredients and this may also be determined at this time.

[0038] The resulting animal feed may be processed into any suitable form compatible with its end use.In some embodiments, for example, the method may further comprise processing the blended homogenized ingredients into an animal feed in the form of pellets, flakes, or a paste.

[0039] In some embodiments, the homogenized ingredients may be recycled back to the corresponding accumulated batches of macerated and dehydrated food waste. For example, if only a small amount of a particular homogenized ingredient remains after a production run of one animal feed, it may be more efficient to return it upstream in the process than to store it until it can be used for another animal feed that only requires that ingredient in small amounts. Returning the homogenized ingredients to the appropriate accumulated batches should not result in any significant changes in the nutritional properties of the batches (effectively an "average" of the batches).

[0040] Typically, given the nature of food waste and the stringent requirements of animal feed, the food waste that has been macerated and dewatered will also undergo a biosecurity treatment. The biosecurity treatment will be described in further detail below.

[0041] It will be appreciated that some of the animal feed produced according to the present invention may contain meat products and are therefore suitable only for feeding animals that can consume animal feed that may contain meat. Animals that can consume such feed include most omnivores such as chickens and ducks, game birds such as pheasants, and shellfish such as crayfish.

[0042] Although recycling food waste is a key feature of the present invention, the inventors note that other edible materials may be incorporated into the process, provided that doing so does not adversely affect the performance of the present invention. For example, products such as Maltings, Malt Combings, Hominy Meal or Mill Mix sold by Castlegate James may be used as the co-blending material described below, or contribute to the present invention in some other advantageous manner. Other edible products such as trace ingredients, for example, may also be incorporated at appropriate stages of the process if advantageous.

[0043] In its second aspect, the present invention provides a method for dehydrating macerated food waste (or, indeed, any moisture containing material). The method comprises mixing into the macerated food waste, near the inlet of a dehydrator, a material having a moisture content different from that of the macerated food waste, wherein the added material and the macerated food waste are mixed so that the mixture fed into the dehydrator has a defined and substantially uniform moisture content.

[0044] As described above, mixing the material (typically relatively dry material) into the macerated food waste shortly before the resulting mixture is fed into the dehydrator ensures that the material presented to the dehydrator always has a relatively consistent moisture content, and a moisture content suitable for the dehydrator. Thus, the dehydrator can be operated to dehydrate the substance of the mixture with a particular efficiency and with a reduced risk of thermal damage to the material.

[0045] As with other aspects of the invention, the macerated food waste is typically sourced from one of a plurality of classified food waste generators and is maintained separate from other categories of food waste. However, again, this need not be the case for all embodiments of this particular aspect of the invention.

[0046] The method includes adding a material having a moisture content different from that of the macerated food waste to the macerated food waste near the inlet of the dehydrator. Typically, a relatively dry material is added to the relatively moist macerated food waste, but this need not always be the case.

[0047] Keeping in mind the context of the present invention, any material can be added to the macerated food waste. In some embodiments, for example, a stock of previously dried materials such as bakery meal or spent brewer's grains can be maintained for this purpose. Commercially available products such as those sold by Castlegate James and listed above can also be used, although additional costs are required. Alternatively, macerated and dried food waste from downstream of the method of the present invention can be used, for example from a food waste generator of the same category as the macerated food waste entering the dehydrator.

[0048] The amount, relative moisture content, and mixing technique of the food will all affect the properties of the resulting mixture entering the dehydrator. The amount of material added to the soaked food can, for example, be adjustable to obtain a specific moisture content. Similarly, the rate at which the material is added to the soaked food is adjustable to achieve a specific moisture content.

[0049] The method also includes mixing the added material and the macerated food waste in a manner such that the resulting mixture fed into the dehydrator has a defined and substantially uniform moisture content. Such mixing can be achieved using any conventional technique, and preferably a technique that compresses the material into the macerated food waste, thereby allowing rapid moisture exchange between relatively moist / drier materials. In the embodiments described herein, an auger is used to mix the added material and the macerated food waste, but other equipment can be used to achieve similar results.

[0050] The specified moisture content (ie, the moisture content of the mixture fed to the dehydrator) may be between about 5% and 80%, between about 20% and 70%, between about 30% and 60%, and more preferably about 50% (w / w).

[0051] Dehydration of the mixture can be carried out using any commercially available dehydrator. Many experiments by the inventors have been carried out using a dehydrator from AKT International and as described in, for example, International (PCT) Patent Application No. PCT / AU89 / 00475, the contents of which are hereby incorporated into this specification in their entirety.

[0052] Typically, dehydrating the mixture comprises agitating the mixture in a stream of hot air. Typically, the temperature of the hot air is about 350°C and the dehydration time is less than 10 seconds. Specific embodiments of the dehydrator are described in further detail below.

[0053] In some embodiments, the method may further include measuring the moisture content of the dehydrated macerated food waste. Such measurements can advantageously provide feedback for the operating parameters of the dehydrator (e.g., the temperature of the dehydrator, the feed rate of the material entering the dehydrator, and the residence time of the material in the dehydrator). For example, if the moisture content of the dehydrated granulated powder leaving the dehydrator is considered to be too high, the operating parameters of the dehydrator can be adjusted (preferably automatically adjusted by the computer operating system controlling the process) to produce a greater amount of dehydration. Similarly, if the moisture content of the dehydrated granulated powder leaving the dehydrator is considered to be too low, the operating parameters of the dehydrator can be adjusted to produce a smaller amount of dehydration.

[0054] The moisture content of the dehydrated granular material leaving the dehydrator may be between about 1% and 12%. Materials with a moisture content above 12% are highly susceptible to microbial growth during storage. Thus, preferably, the moisture content of the dehydrated granular material leaving the dehydrator is less than about 10% or about 8%. Materials with a moisture content below 8% are generally less susceptible to microbial growth during storage.

[0055] In a third aspect, the present invention provides an apparatus for dehydrating macerated food waste (or more generally, any moisture-containing material). The apparatus comprises: a hopper, the outlet of which leads to the inlet of a dehydrator; a moisture detector configured to detect the moisture content of the material near the outlet of the hopper; a conduit through which material having a moisture content different from the moisture content of the macerated food waste can be added to the macerated food waste near the outlet of the hopper; and a mixer for mixing the material and the macerated food waste in a manner such that the resulting mixture presented to the inlet of the dehydrator has a specified and substantially uniform moisture content.

[0056] The apparatus of the third aspect is configured to perform the method of the second aspect, although not limited thereto. In some embodiments, the apparatus may comprise further features enabling it to perform any and all embodiments of the method.

[0057] The assembly comprises a hopper, the outlet of which leads to the inlet of a dehydrator. Specific embodiments of the hopper and the dehydrator will be described in more detail below.

[0058] The device also includes a moisture detector, which is configured to detect the moisture content of the soaked food waste at the outlet / dehydrator entrance adjacent to the hopper. Moisture detectors such as the MCT460 online intelligent NIR sensor series produced by KPM Analytics are expected to be suitable for this purpose. In some embodiments, the detector configured to detect moisture can also be configured to detect other properties of the analyzed material. Such properties can include its fat and / or protein content. Although more expensive, the moisture detector providing such enhanced functionality can provide advantages in terms of performance of the present invention.

[0059] The apparatus further comprises a conduit through which a material having a moisture content different from that of the macerated food waste can be added to the macerated food waste near the outlet of the hopper. The conduit can be provided in any suitable form, such as a pipe extending to the hopper, with its outlet near the outlet of the hopper.

[0060] The device also includes a mixer, which is used to mix the material and the macerated food waste in a certain way, so that the resulting mixture presented to the inlet of the dehydrator has a specified and substantially uniform moisture content. Similarly, in the context of the present invention, any device that can provide this function can be used for such mixing. For example, in the embodiments described below, an auger is used to mix the macerated food waste and other materials when they are fed to the dehydrator. Those skilled in the art will recognize other suitable devices for this purpose.

[0061] In some embodiments, the apparatus may further include a second moisture detector configured to detect the moisture content of the dehydrated macerated food waste leaving the dehydrator. Similar to what is described above in the context of the second aspect, the operating parameters of the dehydrator (e.g., temperature, material feed rate, and residence time) may be adjusted based on the measured moisture content of the dehydrated macerated food waste leaving the dehydrator.

[0062] In a fourth aspect, the present invention provides a method for producing a dehydrated granular powder from macerated food waste (or, indeed, other moisture-containing material). The method comprises dehydrating the macerated food waste to produce a (still warm / hot) dehydrated product, and then stirring the dehydrated product as it cools. In this way, the dehydrated product is prevented from agglomerating and a granular powder is produced.

[0063] Advantageously, it has been found that this aspect of the invention prevents granular particles of food waste from clumping, which can occur when some types of food waste cool after being heated. Dehydration of the macerated food waste may be accomplished using any suitable technique, such as those disclosed herein (although it should be understood that the invention is not limited thereto).

[0064] After dehydration, the still warm dehydrated product is stirred as it cools in a manner that prevents the product from clumping. In the embodiments described in further detail below, the dehydrated product is cooled in an auger where it is continually turned over by the screw as it moves through the (optionally cooled) sleeve. However, it will be appreciated that many other devices can provide similar functionality.

[0065] The particle size of the cooled, dehydrated granulated powder is typically between about 1-3 mm.

[0066] The inventors have noticed that some dehydrated granulated powders can clump when they leave the dehydrator at a temperature of about 50-70° C. and begin to cool. However, this has been found to be a greater problem in processes that also include a biosafety step (as described below), where higher temperatures and longer residence times are required.

[0067] The method of the fourth aspect may also include biosafety treatment before the cooling step of the dehydrated granulated powder. Although the biosafety step can be performed at different stages of the whole process, the operation efficiency can be improved when the still warm material is subjected to biosafety treatment.

[0068] The biosecurity of food products is critical when they are sold to consumers, but there is less regulation when it comes to food waste. However, if food waste is used to produce animal feed, the biosecurity of the food waste is critical, as unsafe feed can pose many threats to animal welfare. For example, such threats can include African swine fever, Aujeszky's disease, and brucellosis in pigs; arboviruses, avian adenoviruses, and avian influenza in poultry; and foot-and-mouth disease in livestock.

[0069] In biosafety heat treatment, the material must be heated at a temperature and time that effectively kills all pathogens (including all microorganisms, such as bacteria and fungi) and all viruses. Biosafety heating schemes may be governed by regulations, based on scientific evidence or empirical determination, but all result in the inactivation of all pathogens. The inventors have found that heating the dehydrated granular powder of food waste at a temperature of at least 100° C. (this is the temperature experienced by the powder, not necessarily the chamber temperature) for at least 30 minutes (e.g., 30-35 minutes) can effectively kill all potential microorganisms. Higher temperatures can be used, but heating to such a temperature will have an adverse effect on the nutritional content of the resulting biosafety product.

[0070] Once biosafety heat treatment is carried out, the biosafety product is cooled. At this moment, relevant measurements, such as the weight of the biosafety product, can be carried out. Due to exposure to environmental conditions, cooling can occur naturally, or a coolant (e.g., the cooled sleeve of the auger as described above) can be used to control. Cooling may require appropriate time, and generally occurs in the time period between about 3 to about 15 minutes.

[0071] Biosafety processing can be carried out in any suitable equipment such as an auger.

[0072] In a fifth aspect, the present invention provides an infuser assembly, the infuser assembly comprising an infuser having an inlet and an outlet, the inlet being connectable to the outlet of a storage container, and the infuser being movable between a plurality of storage containers.

[0073] Specific embodiments of the macerator assembly will be described below. However, in general, the macerator assembly may include a track (or other moving device, such as a conveyor belt) along which the macerator can slide in alignment with the outlet of one of the plurality of storage containers. The macerator assembly may also include a lifting assembly for lifting the macerator so that the inlet is coupled to the outlet of one of the plurality of storage containers.

[0074] Now refer to Figure 1Specific embodiments of methods for producing animal feedstock from multiple sorted food waste streams and incorporating various embodiments of aspects of the invention are described.

[0075] Figure 1 is a schematic / flow chart of a process 10 in which starting materials in the form of classified food waste are processed to produce animal feed that is sold to the market. Advantageously, the animal feed produced has a well-defined nutritional profile that meets consumer demand and can therefore fetch a high price. Furthermore, since the raw materials for the product are traditionally considered waste products, the production cost should be significantly lower than traditional animal feed manufacturing costs. Finally, the environmental benefits of beneficially using food waste to produce a marketable product are significant.

[0076] exist Figure 1 The following symbols are used:

[0077] Explanation of symbols

[0078] Aerodynamics (forward)

[0079] Aerodynamics (backward)

[0080] Exquisite materials

[0081] Flexible auger

[0082] Wet pumping

[0083] Wet pumping

[0084] In process 10, for example, classified food waste collected, stored and transported as described in PCT / AU2017 / 051130 is delivered to a set of classified food waste bins 12. Bins 12A to 12N are physically separated from each other and each receives the same category of food waste. For example, bin 12A may be designated to receive waste from a bakery, while bin 12B is designated to receive waste from a butcher's shop, etc. As each successive delivery of recently collected food waste arrives, any bakery waste will be added to bin 12A, and any meat waste will be added to bin 12B. As described in PCT / AU2017 / 051130, each of these categories of food waste will have similar nutritional content.

[0085] Once each bin 12 reaches a predefined capacity (or after a predetermined period of time, taking into account the spoilage potential of the food waste), a macerator and pump assembly, generally shown as a macerator 14, is used to macerate the food waste in each respective bin 12 and pump the macerated food waste through a line 16 into a hopper (not shown) and subsequently into a dehydrator 20. The macerator 14 is located on tracks 22, which enables it to be moved laterally under successive bins 12. In use, the macerator 14 will be moved into a position adjacent to a corresponding bin (e.g., bin 12A) in which position it can be coupled to an outlet (not shown) of the bin. Opening the outlet of the bin 12 causes the food waste in the bin to fall into the macerator 14, where it is macerated and subsequently pumped to the dehydrator 20. For example, the macerator 14 can be lifted into a position where such coupling can occur, although other movements having the same effect are certainly possible.

[0086] A fixed macerator 18 may also be provided in communication with a designated bin (e.g., bin 12H). The macerator 18 may be specifically configured for macerating larger or harder food wastes. For example, a smaller macerator may not be able to engage relatively large items, such as whole cabbages or cauliflowers, and therefore may not be macerated. Oyster shells or bones may also require a more robust macerator. Providing a designated macerator 18 for such relatively large food wastes further increases processing capacity.

[0087] Once the respective bin 12 is emptied, flushing may occur. A small amount of water may be sprayed into the bin 12, flushing the bin walls and effectively cleaning them. The wash water, entraining any remaining food waste, may enter the macerator 14 and then be pumped to the dehydrator 20.

[0088] The dehydrator 20 is operated under conditions that dehydrate the macerated food waste presented to the dehydrator. In the dehydrator used by the inventors in their experiments described in PCT / AU89 / 00475, hot air (about 350°C) was blown through the chamber, introducing the macerated food waste into the chamber. A rotating arm suspended from a central axis impacted the macerated food waste, causing it to be further pulverized and propelled into the hot air. After just 10 seconds, a granular powder was formed in the drying chamber, which was entrained in the air flow and carried out of the chamber. A cyclone separator (not shown) was then used to separate the granular particles from the hot air and moisture. The granular powder left the cyclone's airlock valve through the dehydrator outlet line 24 and was further processed as described below.

[0089] In process 10, two dehydrators 20A and 20B are depicted, one larger than the other, having a diameter of about 1.5 m 3 / hour (20A) maximum output, rather than about 1.0m3 / hour (20B). Dehydrators 20A and 20B may be operated independently, separately or together, as desired to maximize the overall efficiency of process 10.

[0090] The operation of the dehydrator 20 (both dehydrators 20A and 20B operate in the same manner) involves monitoring a number of parameters, many of which the inventors anticipate will be automated. One of these parameters is the moisture content of the macerated food waste fed into the dehydrator 20, which is ideally about 50%. Dehydration is also more efficient when the material entering the dehydrator 20 has a relatively consistent moisture content, which is not always the case for food waste. Therefore, in order to better control the moisture content of the macerated food waste presented to the dehydrator 20, a dry co-blending operation described below may be used.

[0091] The dehydrated food waste in line 24 may be directed to silo 30 via line 28 for temporary storage. When shredded food waste having too high a moisture content is presented to dehydrator 20, a quantity of dehydrated food waste from silo 30 may be provided via line 34, typically in the form of a flexible auger (not shown), to a hopper (not shown) for mixing with the shredded food waste so that the resulting mixture entering dehydrator 20 always has a reduced and relatively consistent moisture content.

[0092] The inventor also notes that waste brewer's grains are food wastes containing a large amount of nutrients, and there are problems in handling. Since such food waste does not need to be soaked, it can be stored separately in the silo 34 and fed into the dehydrator 20 at the appropriate time (for example, when there is no other food waste to be dehydrated in the box 12). The inventor notes that the brewer's grains through dehydration are also suitable dry common blending materials and can be used specifically for this purpose. Another kind of food waste that can be used as common blending material is bread meal. Other products that can be used include the products sold by Castlegate James and described above, any of which can be stored in the silo 30 / 34.

[0093] The dehydrated pulverized food waste leaving the dehydrator 20 can be further processed to ensure that it is biosafe. Such processing can be carried out in the assembly described below. In the biosafety heat treatment, the dehydrated granulated powder must be heated at a temperature and time that effectively kills all pathogens (including all microorganisms, such bacteria and fungi) and all viruses. In this embodiment, the material is heated at a temperature of at least 100° C. for at least 30 minutes (e.g., 30-35 minutes) (this is the temperature experienced by the product, not necessarily the chamber temperature).

[0094] Heating occurs in a first auger (not shown), the inlet of which is configured to receive the dehydrated product from line 24. The heater around the shaft of the auger heats the material inside to the desired temperature, and the screw turns at a certain rate, thereby controlling the residence time of the material in the auger. At the end of the biosafety treatment, the biosafety granular powder cools, and the inventors have found that this cooling should be ideally controlled to prevent the powder from agglomerating (this is particularly a problem for food waste with relatively high fat or protein content). The inventors have found that stirring the material while the material is cooling prevents the occurrence of agglomeration and produces a granular powder that is relatively easy to handle in the downstream process (it has a substantially uniform particle size and can be moved using pneumatic conveying technology). In these embodiments, a second auger (not shown) is used, wherein the hot biosafety granular powder leaving the first auger falls directly into the second auger, where the cooling process begins. Cooling can occur naturally, or can be caused by applied cooling (e.g., to the sleeve of the auger). Similarly, the cooling time depends on the rate at which the screw of the auger turns. The inventors have found that the constant tumbling action of the screw is sufficient agitation to prevent agglomeration.

[0095] The sorted, dehydrated, shredded and biosecured food waste is then transferred (e.g., by pneumatic conveying, all downstream steps in process 10 are dry) to an array of silos 26. Each silo in the array of silos 26 (e.g., silo 26A) holds a defined class of dehydrated, shredded and biosecured food waste, with successive batches of the same class of similarly processed food waste (i.e., originating from the same class of food waste generators, such as bakeries) being added to silo 26A. In this manner, stratified bulk quantities of food waste are accumulated in each silo 26A, ready for further processing in the manner described below.

[0096] Each successive batch of properly sorted and processed food waste transferred to a particular silo (e.g., silo 26A) will have similar nutritional characteristics, coming from the same source, despite slight differences in the batches. However, the nutritional characteristics of the accumulated food waste in other silos (e.g., silo 26B, etc.) being different classes of food waste and originating from different classes of food waste generators (e.g., butcher shops) will differ significantly.

[0097] Once the amount of material in any given silo 26 (e.g., silo 26A) reaches a certain level (e.g., determined by the weight of the silo or by sensors within the silo), the contents of the silo are pneumatically conveyed to a batch mixer 36 where vigorous mixing occurs to completely homogenize the material. The material so mixed is pneumatically conveyed to a corresponding silo in the array of silos 38 (e.g., silo 38A) and the ingredients or raw materials available for blending are now defined to produce animal feed. A physical sample (e.g., about 1 L of ingredients) is removed from one of the silos 38 (e.g., silo 38A) and analyzed for parameters such as its protein content, fat content, moisture content, specific gravity, and amino acid profile. Thus, the ingredients stored in each silo 38 are well characterized in terms of quality for addition to animal feed.

[0098] Thus, the silos 38 contain a number of uniform ingredients, all of which have well-characterized nutritional properties and are in physically similar form (i.e., dry, granular particles). These ingredients are immediately available for blending together to produce the resulting animal feed. To this end, calculated proportions of the various ingredients from the various silos 38 are pneumatically conveyed to the batch mixer 40. If desired, micro ingredients from the silos 42 may also be added to the batch mixer at this time along with any other ingredients that may be desired. Although not shown, the micro ingredients are typically each stored in their own distinct silo 42 to maximize the opportunity for blending.

[0099] The batch mixer 40 homogenizes the ingredients and any added micronutrients, thus producing an animal feed having the desired specifications. The animal feed so produced is pneumatically conveyed to a storage silo 44 (if necessary), and then subsequently conveyed to a packaging facility 46. In the packaging facility, the animal feed can be pelletized if necessary and bagged (bulk or small size (e.g., 20 kg) bags). Alternatively, the animal feed can be loaded into a silo 48 for storage until it is subsequently loaded onto a truck for off-site transportation (e.g., to a chicken farm that requires bulk feed).

[0100] This is what the inventors consider to be the main advantage of this aspect of the invention, namely that the method uses only recycled food waste, so that many ingredients have significantly different nutritional properties and can be used for blending to produce a saleable product (e.g., animal feed). The inventors have not previously considered that when used to produce animal feeds such as chicken feed, batch variations between successive deliveries of the same category of food waste may have potential harmful effects, in which case any deviation from the precise nutritional properties is unacceptable. However, the homogenization, analysis and blending steps described herein enable the production of animal feeds with precise nutritional content (such as required for feeds such as chicken feed) as required and in fact any given requirement.

[0101] The process 10 also includes a recycle line 50, which can be used to recycle products from the process to any upstream stage of the process. For example, if there is only a small amount of an ingredient in a particular silo 38, and a new ingredient requires that silo, the remaining ingredient can be pneumatically transported back to the appropriate silo 26, or even back to the dehydrator 20, for example as a co-blended material.

[0102] It should be understood that the present invention provides many new and useful advantages. For example, specific embodiments of the present invention may provide one or more of the following advantages:

[0103] ● Less food waste sent to landfill;

[0104] • Saleable, high-quality animal feed can be produced at relatively low ongoing cost (i.e. due to relatively cheap supply of food waste components) and potentially solely from collected food waste;

[0105] • A wide variety of food wastes can be processed to produce ingredients with a correspondingly wide variety of nutritional properties, which can be blended to produce animal feeds with virtually any nutritional properties;

[0106] ● A recirculation line will help utilize every bit of food waste in the process; and

[0107] - The environmental benefit of beneficially reusing food waste as an ingredient in animal feed, rather than having to rancidify commercial ingredients that could otherwise be put to more beneficial use - such as human food.

[0108] Those skilled in the art of the present invention will appreciate that many modifications may be made without departing from the spirit and scope of the present invention. All such modifications are intended to fall within the scope of the following claims.

[0109] In the accompanying claims and the foregoing description of the invention, unless the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" are used in an inclusive sense, i.e. the presence of specified recited features but does not exclude the presence or addition of further features in various embodiments of the invention.

[0110] It should be appreciated that citation of any prior art publication herein does not constitute an admission that the publication forms part of the common general knowledge in the art.

Claims

1. A method for producing an animal feed having defined nutritional properties from food waste, the method comprising: accumulating successive batches of a plurality of food wastes that have been macerated and dehydrated, each batch of each of the plurality of food wastes originating from a same classified food waste generator among a plurality of classified food waste generators, and maintained at all times separately from other food wastes in the plurality of food wastes; independently blending each of the accumulated batches of macerated and dehydrated food waste to produce a plurality of homogenized components for animal feed; analyzing each of the homogenized ingredients to determine one or more nutritional parameters of the ingredient; as well as Two or more of the homogenized ingredients are blended to produce the animal feed having the specified nutritional properties.

2. The method of claim 1, wherein said blending comprises determining the relative amounts of each of said homogenized ingredients required to produce said animal feed having specified nutritional properties.

3. A method according to claim 1 or claim 2, wherein the one or more nutritional parameters of the ingredients are independently selected from one or more of the following: protein content, fat content, amino acid content and specific gravity.

4. The method according to any one of claims 1 to 3, wherein each of the accumulated batches of the soaked and dehydrated food waste are mixed once the size of the accumulated batches reaches a predetermined threshold.

5. A method according to any one of claims 1 to 4, wherein one or more of the homogenised ingredients can be recycled back to a corresponding one or more of the accumulated batches of the soaked and dehydrated food waste.

6. A method according to any one of claims 1 to 5, wherein the food waste which has been macerated and dehydrated has also been subjected to a biosafety treatment.

7. The method according to any one of claims 1 to 6, wherein each of the sorted food waste generators is selected from the group consisting of: restaurants, cafes, supermarkets, grocery stores, greengrocers, delicatessens, butchers and bakeries.

8. The method of any one of claims 1 to 7, further comprising processing the blended homogenized ingredients into an animal feed in the form of pellets, flakes or paste.

9. The method according to any one of claims 1 to 8, further comprising adding micro-ingredients to the homogenized ingredients.

10. A method for dehydrating macerated food waste, the method comprising: mixing a material having a moisture content different from that of the macerated food waste into the macerated food waste near an inlet of a dehydrator, wherein the added material and the macerated food waste are mixed such that the mixture at the inlet of the dehydrator has a specified and substantially uniform moisture content; and The mixture was dehydrated.

11. The method of claim 10, wherein the amount of said material added to said macerated food waste is adjustable to achieve said specified moisture content.

12. A method according to claim 10 or claim 11, wherein the rate at which the material is added to the soaked food waste is adjustable to achieve the specified moisture content.

13. A method according to any one of claims 10 to 12, wherein mixing comprises compressing the material and the soaked food waste together.

14. A method according to any one of claims 10 to 13, wherein an auger mixes the added material and the macerated food waste.

15. The method according to any one of claims 10 to 14, wherein the specified moisture content is about 50% (w / w).

16. The method of any one of claims 10 to 15, wherein dehydrating the mixture comprises agitating the mixture in a stream of hot air.

17. The method of claim 16, wherein the temperature of the hot air is about 350°C and the dehydration time is less than 10 seconds.

18. The method of any one of claims 10 to 17, further comprising measuring the moisture content of the dehydrated mixture.

19. The method of claim 18, wherein an operating parameter of the dehydrator is adjustable based on the measured moisture content of the dehydrated mixture.

20. The method of claim 19, wherein the operating parameters are selected from one or more of the following: temperature of the dehydrator, feed rate into the dehydrator, and residence time in the dehydrator.

21. The mixture of any one of claims 18 to 20, wherein the moisture content of the dehydrated mixture is between about 1% and about 12%.

22. The method of any one of claims 10 to 21, wherein the macerated food waste originates from one of a plurality of classified food waste generators.

23. A mixture according to any one of claims 10 to 22, wherein relatively dry material is added to the relatively moist macerated food waste.

24. An apparatus for dehydrating macerated food waste, the apparatus comprising: a hopper, the outlet of the hopper leading to the inlet of the dehydrator; a moisture detector configured to detect moisture content near the outlet of the hopper; a conduit through which a material having a moisture content different from the moisture content of the macerated food waste can be added to the macerated food waste proximate the outlet of the hopper; as well as A mixer for mixing the material and the macerated food waste in a manner whereby the resulting mixture presented to the inlet of the dehydrator has a specified and substantially uniform moisture content.

25. The assembly of claim 24 including an auger for mixing the material and the macerated food waste and feeding the resulting mixture into the dehydrator.

26. An assembly according to claim 24 or claim 25, further comprising a second moisture detector configured to detect the moisture content of the dehydrated soaked food waste exiting the dehydrator.

27. A method for producing a dehydrated granulated powder from macerated food waste, the method comprising: dehydrating the soaked food waste to produce a dehydrated product; as well as The dehydrated product is stirred as it cools, thereby preventing agglomeration and producing the dehydrated granulated powder.

28. The method of claim 27, wherein the dehydrated product is cooled over a period of time between about 3 and about 15 minutes.

29. A method according to claim 27 or claim 28, wherein the particle size of the cooled dehydrated granulated powder is between about 1-3 mm.

30. The process of any one of claims 27 to 29, wherein the dewatered product is cooled in an auger.

31. The method of any one of claims 27 to 30, further comprising subjecting the dehydrated product to biosafety treatment prior to cooling.

32. The method of claim 31 , wherein the biosafety treatment comprises maintaining the dehydrated product at a temperature of at least 100°C for a period of at least 30 minutes.

33. A method according to claim 31 or claim 32, wherein the biosecurity treatment is carried out in an auger.

34. The method of any one of claims 27 to 33, wherein the macerated food waste originates from one of a plurality of classified food waste generators.

35. An infuser assembly comprising: a macerator having an inlet and an outlet; The inlet is connectable to the outlet of the storage container; and The macerator is movable between a plurality of storage containers.

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