Systems and methods for mechanically recycling a plastic waste stream

Abstract

A system for mechanically recycling a plastic waste stream can include first and second size reduction units, a washing system, a drying system, and an extrusion unit. The first and second size reduction units can respectively receive and shred first and second plastic waste streams to respectively produce first and second shredded plastic waste streams. The washing system (positioned downstream from the first size reduction unit) can receive and wash the first shredded plastic waste stream to produce a washed plastic material stream. The drying system (positioned downstream from the washing system) can receive and dry the washed plastic material stream to provide a dried plastic material stream. The extrusion unit (positioned downstream from the drying system and the second size reduction unit) can receive, melt, and extrude the dried plastic material stream and / or the second shredded plastic waste stream to produce a mechanically recycled plastic material.

Description

[0001] SYSTEMS AND METHODS FOR MECHANICALLY RECYCLING

[0002] A PLASTIC WASTE STREAM

[0003] TECHNICAL FIELD

[0004] The present invention generally relates to wet and dry mechanical recycling processes for polymer compositions, and more particularly to hybrid wet / dry mechanical recycling process configurations.

[0005] BACKGROUND ART

[0006] Two basic manufacturing configurations are generally commercially employed in the recycling industry to process recycled polymer feedstocks into a useable pellet form. The first of the two basic manufacturing configurations is generally referred to as a “wet” process, and the second of the two basic manufacturing configurations is generally referred to as a “dry” process.

[0007] A wet process typically includes bale de-wiring, bale breakup, shredding, screening, optical sorting, washing, drying, melt filtration, extrusion, devolatilization, and pelletization. One benefit of such a configuration is that it can process a wide range of feedstock with various degrees of dirt and / or other contamination. Among various drawbacks, such a configuration may be expensive both in terms of capital and operating costs with high energy and water consumption, chemicals, and maintenance requirements. Such costs can be especially high if thin gauge recycled films (such as stretch) are used as a feedstock because of the challenges associated with washing and drying films with a large surface area. An oversized extruder and drying capabilities are typically required in order to accommodate the high moisture content of material coming from the wash line, even after drying.

[0008] In a dry process, the washing and drying elements of the aforementioned wet process are typically eliminated. Among various drawbacks, such a dry configuration may be limited to use with a “clean” feedstock (e.g., having little or no contamination), and such a feedstock may be available in limited quantities and at a higher cost. However, benefits associated with a dry configuration may include significantly lower capital and operating costs relative to a wet configuration. Another potential benefit associated with a dry configuration is that the extruder may be capable of operating efficiently at full capacity because the material entering the extruder is dry.

[0009] SUMMARY OF INVENTION

[0010] A solution to at least one or more of the aforementioned problems is disclosed herein. In some instances, the solution may include allowing a recycling system to be operated either as a “wet” process, a “dry” process, or as a combination of the two configurations. The operation modes can be modified based on the recycling feed stock (e.g., feedstock having low or high contaminants). This can be beneficial, as it can allow for improvements in product output, costs, and quality (or any combination thereof) for a given feedstock type.

[0011] In some embodiments, the present disclosure describes a system for mechanically recycling a plastic waste stream that includes a first size reduction unit, a second size reduction unit, a washing system, a drying system, and an extrusion unit. The first size reduction unit may be configured to receive and shred a first plastic waste stream to produce a first shredded plastic waste stream. The second size reduction unit may be configured to receive and shred a second plastic waste stream to produce a second shredded plastic waste stream. The washing system (operatively connected to and positioned downstream from the first size reduction unit) may be configured to receive and wash the first shredded plastic waste stream to produce a washed plastic material stream. The drying system (positioned downstream from the washing system) may be configured to receive and dry the washed plastic material stream to provide a dried plastic material stream. The extrusion unit (positioned downstream from the drying system and the second size reduction unit) may be configured to receive, melt, and extrude one or both of the dried plastic material stream and the second shredded plastic waste stream to produce a mechanically recycled plastic material.

[0012] In some embodiments, the first and second plastic waste streams for mechanical recycling by the system may each include film plastic. In some embodiments, the first plastic waste stream may include contaminated plastic material, and the second plastic waste stream may include uncontaminated plastic material. In various embodiments, examples of contaminants that may be associated with the contaminated plastic material include dirt, grit, organic waste, paper, label adhesive, cellulose (e.g., from paper), nylon (e.g., from strapping or multilayer structures with nylon), polypropylene, polyethylene terephthalate, metal, or a combination thereof. In various embodiments, the uncontaminated plastic material (e.g., “high quality” plastic material) may include less than 10% contamination.

[0013] In some embodiments, the system may include at least one pre-wash sorter positioned between the first size reduction unit and the washing system. The at least one pre-wash sorter may be configured to identify and remove at least a portion of plastic material in the first shredded plastic waste stream that exceeds a maximum contamination level, thereby providing a first sorted shredded plastic stream. In various embodiments, the at least one prewash sorter may include an optical sorter. In some embodiments, the system may include first and second conveyors, each operatively connected to the pre-wash sorter(s). The first conveyor may be configured to transport the first sorted shredded plastic stream from the pre-wash sorter(s) to the washing system. The second conveyor may be configured to transport the at least a portion of plastic material (that exceeds the maximum contamination level) from the pre-wash sorter(s) to a waste unit. In a particular embodiment, the system may include a controller configured to control operation of the first conveyor, the second conveyor, or a combination thereof.

[0014] In some embodiments, the system may include at least one pre-extrusion sorter positioned between the second size reduction unit and the extrusion unit. The pre-extrusion sorter(s) may be configured to identify contaminated plastic material and uncontaminated plastic material in the second shredded plastic waste stream. In various embodiments, the at least one pre-extrusion sorter may include an optical sorter. In some embodiments, the system may include first and second conveyors, each operatively connected to the pre-extrusion sorter(s). The first conveyor may be configured to transport at least a portion of the contaminated plastic material in the second shredded plastic waste stream from the pre- extrusion sorter(s) to or upstream of the pre-wash sorter(s) or the washing system. The conveyor may be configured to transport the uncontaminated plastic material in the second shredded plastic waste stream from the pre-extrusion sorter(s) to the extrusion unit. In one embodiment, when the at least one pre-extrusion sorter identifies contaminated plastic material in the second shredded plastic waste stream, the first conveyor may be automatically actuated to transport the contaminated plastic material in the second shredded plastic waste stream to or upstream of the pre-wash sorter(s) or the washing system. When the at least one pre-extrusion sorter identifies uncontaminated plastic material in the second shredded plastic waste stream, the second conveyor may be automatically actuated to transport the uncontaminated plastic material in the second shredded plastic waste stream to the extrusion unit.

[0015] In some embodiments, the system may include a holding unit positioned between the pre-extrusion sorter(s) and the extrusion unit. The holding unit may be configured to receive the second shredded plastic waste stream from the pre-extrusion sorter(s), and the holding unit may be operatively connected to pre-extrusion sorter(s), a first conveyor, and a second conveyor. The first conveyor may be configured to transport the second shredded plastic waste stream from the holding unit to or upstream of the pre-wash sorter(s) or the washing system, and the second conveyor may be configured to transport the second shredded plastic waste stream from the holding unit to the extrusion unit. In various embodiments, the system may include a controller configured to control operation of the first conveyor, the second conveyor, or a combination thereof.

[0016] The present disclosure further describes methods of mechanically recycling plastic waste with various embodiments of the aforementioned system of the present disclosure. In some embodiments, the method may include subjecting the first plastic waste stream to the first size reduction unit to obtain the first shredded plastic waste stream and subjecting the second plastic waste stream to the second size reduction unit to obtain the second shredded plastic waste stream. The method may also include subjecting the first shredded plastic waste steam to the washing system to obtain the washed plastic material stream and subjecting the washed plastic material stream to the drying system to obtain the dried plastic material stream. The method may further include subjecting the dried plastic material stream to the extrusion unit to obtain a first mechanically recycled material, subjecting the second shredded plastic waste stream to the extrusion unit to obtain a second mechanically recycled material, or a combination thereof.

[0017] In some embodiments, the first plastic waste stream and the second plastic waste stream may be processed simultaneously such that the mechanically recycled product produced comprises the first mechanically recycled material and the second mechanically recycled material. In other embodiments, the first plastic waste stream and the second plastic waste stream may be processed at different times such that a first product is produced that comprises the first mechanically recycled product and a second product is produced that comprises the second mechanically recycled material. In various embodiments, the method may also include identifying contaminated plastic material in the second shredded plastic waste stream and diverting at least a portion of the contaminated plastic material.

[0018] BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a block diagram illustrating a simplified example of a system for mechanically recycling plastic waste, according to various aspects of the present disclosure.

[0020] Figure 2 is a block diagram illustrating a first example of a system for mechanically recycling plastic waste, according to various aspects of the present disclosure.

[0021] Figure 3 is a block diagram illustrating a second example of a system for mechanically recycling plastic waste, according to various aspects of the present disclosure.

[0022] Figure 4 is a flow diagram illustrating a first example of a method of mechanically recycling plastic waste, according to various aspects of the present disclosure.

[0023] Figure 5 is a flow diagram illustrating a second example of a method of mechanically recycling plastic waste, according to various aspects of the present disclosure. DESCRIPTION OF EMBODIMENTS

[0024] The present disclosure describes systems and methods for mechanically recycling plastic waste. In some aspects, the systems and methods of the present disclosure may be utilized to retrofit an existing “wet” mechanical recycling process or to design a new recycling facility in order to allow the system to be operated either as a “wet” process, a “dry” process, or as a combination of the two configurations. Accordingly, the systems and methods of the present disclosure may provide solutions to a variety of the aforementioned problems / shortcomings associated with existing manufacturing configurations commercially employed in the recycling industry to process recycled polymer feedstocks into a useable pellet form. For example, the systems and methods of the present disclosure may potentially allow for improvements in product output, costs, and quality (or any combination thereof) for a given feedstock type (among numerous other potential advantages as described further herein).

[0025] As used herein, the term “contaminant” broadly refers to any material other than a particular plastic to be mechanically recycled. As used herein, the term “contamination” broadly refers to the presence of one or more contaminants in a particular plastic to be mechanically recycled.

[0026] As used herein, the terms “contaminated material” or “contaminated plastic material” refer to a plastic material that contains a level of contamination that exceeds a particular threshold level of contamination for a given application.

[0027] As used herein, the terms “uncontaminated material” or “uncontaminated plastic material” refer to a plastic material that contains a level of contamination that does not exceed a particular threshold level of contamination for a given application.

[0028] As used herein, the term “monomer” refers to a small molecule that may chemically react and become chemically bonded with itself or other monomers to form a polymer. As used herein, the term “a-olefin” or “alpha-olefin” is used to describe a monomer having a linear hydrocarbon chain containing from 3 to 20 carbon atoms having a double bond at one end of the chain; an equivalent term is “linear a-olefin”. As used herein, the term “polyethylene” or “ethylene polymer”, refers to macromolecules produced from ethylene monomers and optionally one or more additional monomers; regardless of the specific catalyst or specific process used to make the ethylene polymer. In the polyethylene art, the one or more additional monomers are called “comonomer(s)” and often include a-olefins. The term “homopolymer” refers to a polymer that contains only one type of monomer. An “ethylene homopolymer” is made using only ethylene as a polymerizable monomer. The term “copolymer” refers to a polymer that contains two or more types of monomer. An “ethylene copolymer” is made using ethylene and one or more other types of polymerizable monomer. Common polyethylenes include low density polyethylene (LDPE), high density polyethylene (HDPE), medium density polyethylene (MDPE), linear low density polyethylene (LLDPE), very low density polyethylene (VLDPE), ultralow density polyethylene (ULDPE), plastomers and elastomers. The term polyethylene also includes polyethylene terpolymers which may include two or more comonomers in addition to ethylene. The term polyethylene also includes combinations of, or blends of, the polyethylenes described above.

[0029] As used herein, the term “film plastic” refers to a flexible plastic material, such as a thin plastic fdm that may include polyethylene or be substantially made of polyethylene (e.g., an HDPE fdm, an LDPE fdm, an LLDPE fdm, or a fdm including both LDPE and LLDPE), among numerous other possible flexible plastic materials.

[0030] As used herein, the term “rigid plastic” refers to a substantially inflexible plastic material, such as a relatively thick plastic material that may include polyethylene or be substantially made of polyethylene (e.g., a rigid HDPE material), among numerous other possible substantially inflexible plastic materials.

[0031] As used herein, the terms “about” or “approximately” are defined as being close to as understood by one of ordinary skill in the art. In one non-limiting embodiment, the terms are defined to be within 10%, preferably within 5%, more preferably within 1%, and most preferably within 0.5%.

[0032] As used herein, the terms “wt.%”, “% by weight”, “vol.%”, “% by volume”, “mol.%”, or “% by mol.” refers to a weight percentage of a component, a volume percentage of a component, or molar percentage of a component, respectively, based on the total weight, the total volume of material, or total moles, which includes the component. In a non-limiting example, 10 grams of component in 100 grams of the material is 10 wt.% of component.

[0033] As used herein, the terms “inhibiting” or “reducing” or “preventing” or “avoiding” or any variation of these terms, such as “inhibit,” “reduce,” “prevent,” “avoid,” etc., when used in the claims and / or the specification includes any measurable decrease or complete inhibition to achieve a desired result.

[0034] As used herein, the term “effective”, as that term is used in the specification and / or claims, means adequate to accomplish a desired, expected, or intended result.

[0035] As used herein, the use of the words “a” or “an” when used in conjunction with any of the terms “comprising”, “including”, “containing”, or “having” in the claims, or the specification, may mean “one”, but it is also consistent with the meaning of “one or more”, “at least one”, and “one or more than one”.

[0036] As used herein, the words “comprising” (and any form of comprising, such as “comprise” and “comprises”), “having” (and any form of having, such as “have” and “has”), “including” (and any form of including, such as “includes” and “include”) or “containing” (and any form of containing, such as “contains” and “contain”) are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

[0037] The systems for mechanically recycling a plastic waste stream of the present invention and methods for using the same can “comprise”, “consist essentially of’, or “consist of’ particular components, compositions, ingredients, steps etc. disclosed throughout the specification. With respect to the transitional phrase “consisting essentially of’, in one nonlimiting aspect, a basic and novel characteristic of the systems and methods of the present invention is that the hybrid wet / dry recycling configurations of the present invention may provide the ability to process different plastic waste streams either simultaneously or at different times using a wet recycling configuration, a dry recycling configuration, or a combination thereof.

[0038] Referring to Figure 1, a block diagram depicts a simplified example of a system 100 for mechanically recycling a plastic waste stream, according to a particular embodiment. In the simplified example depicted in Figure 1, the system 100 includes a first size reduction unit 110, a second size reduction unit 120, a washing system 130, a drying system 140, and an extrusion unit 150. In Figure 1, the first size reduction unit 110, the washing system 130, the drying system 140, and the extrusion unit 150 of the system 100 are designed to be representative of a simplified “wet” mechanical recycling configuration. In Figure 1, the second size reduction unit 120 and the extrusion unit 150 of the system 100 are designed to be representative of a simplified “dry” mechanical recycling configuration. The system 100 depicted in Figure 1 is designed to be representative of a simplified example of a hybrid wet / dry mechanical recycling system, according to various aspects of the present disclosure. Accordingly, various possible sub-components of the individual components of the system 100 depicted in the simplified example of Figure 1 have been selectively omitted for illustrative purposes only. More detailed examples of hybrid wet / dry mechanical recycling systems (including such possible sub-components selectively omitted from Figure 1) according to various aspects of the present disclosure are illustrated and further described herein with respect to Figures 2 and 3. Referring to Figure 1, the first size reduction unit 110 of the system 100 may be configured to receive and shred a first plastic waste stream 112 to produce a first shredded plastic waste stream 114. The second size reduction unit 120 of the system 100 may be configured to receive and shred a second plastic waste stream 122 to produce a second shredded plastic waste stream 124.

[0039] The washing system 130 of the system 100 may be configured to receive and wash (at least) the first shredded plastic waste stream 114 to produce a washed plastic material stream 132. Figure 1 is designed to illustrate that the washing system 130 is operatively connected to and positioned downstream from the first size reduction unit 110. The skilled person will be familiar with washing systems and any suitable washing system may be used. Nonlimiting examples of washing systems include a sink float separator, a washer, a wet granulator, or any combination thereof. Non-limiting examples of a washer include a turbo washer, a friction washer, a hydrocyclone, or any combination thereof.

[0040] In a particular aspect, the first and second plastic waste streams 112, 122 may each include film plastic. According to some aspects, such film plastic may include polyethylene or be substantially made of polyethylene, including but not limited to HDPE film plastic, LDPE film plastic, LLDPE film plastic, or film plastic including both LDPE and LLDPE. As described further herein, the hybrid wet / dry mechanical recycling systems of the present disclosure (including the system 100 depicted in the simplified example of Figure 1) may be particularly advantageous when the plastic material to be recycled includes film plastic, as such films may be challenging to wash. Accordingly, one potential benefit associated with the hybrid wet / dry mechanical recycling systems of the present disclosure is the ability to avoid washing a “high quality” feedstock that includes film plastic for mechanical recycling. To illustrate, the system 100 of Figure 1 may provide the ability for the second plastic waste stream 122 (e.g., a “high quality” feedstock that may include film plastic, such as HDPE film, LDPE film, LLDPE film, or film including both LDPE and LLDPE) to be mechanically recycled while avoiding the challenges associated with washing film plastic by selectively bypassing the washing system 130. Instead, the simplified example depicted in Figure 1 illustrates that the second shredded plastic waste stream 124 associated with the second plastic waste stream 122 may be conveyed directly to the extrusion unit 150 for melting and extrusion.

[0041] The drying system 140 of the system 100 may be configured to receive and dry the washed plastic material stream 132 to provide a dried plastic material stream 142. Figure 1 is designed to illustrate that the drying system 140 is positioned downstream from the washing system 130. The skilled person will be familiar with drying systems and any suitable drying system may be used. Non-limiting examples of drying systems include a dryer, such as a turbo dryer, a thermal dryer, a plastocompactor, or any combination thereof.

[0042] The extrusion unit 150 of the system 100 may be configured to receive, melt, and extrude one or both of the dried plastic material stream 142 and the second shredded plastic waste stream 124 to produce a mechanically recycled plastic material 152. Figure 1 is designed to illustrate that the extrusion unit 150 is positioned downstream from the drying system 140 and the second size reduction unit 120. The skilled person will be familiar with extrusion units and any suitable extrusion unit may be used. Non-limiting examples of extrusion units include a single screw extruder, a co-rotating twin screw extruder, a counterrotating twin screw extruder, a pelletizing extruder, or any combination thereof. The skilled person will also be familiar with other equipment suitable for homogenizing polyethylene in the molten state such as, for example, a melt pump. As used herein, the term “extrusion unit” is intended to include such homogenizing units.

[0043] In various aspects, the system 100 may include a controller (not shown in the simplified example depicted in Figure 1) configured to control operation of: the first and second size reduction units 110, 120; the washing system 130; the drying system 140; the extrusion unit 150; or any combination thereof. In various embodiments, the system 100 may include a conveyor network (not shown in the simplified example depicted in Figure 1) configured to: transport the individual plastic waste stream 112, 122 to the respective size reduction units 110, 120; at least the first shredded plastic waste stream 114 to the washing system 130; the washed plastic material stream 132 to the drying system 140; and the dried plastic material stream 142 to the extrusion unit 150.

[0044] In some aspects, the first plastic waste stream 112 may include plastic material that includes contamination (also referred to herein as “contaminated” plastic material), and the second plastic waste stream 122 may include “uncontaminated” plastic material (identified in Figure 1 by reference character 126). For example, in some aspects, the “contaminated” plastic material (associated with the first plastic waste stream 112) may include dirt, grit, organic waste, paper, label adhesive, cellulose, nylon, polypropylene, polyethylene terephthalate, metal, or a combination thereof. As another example, in some aspects, the “uncontaminated” plastic material (associated with the second plastic waste stream 122) may include less than 10% contamination (e.g., contamination of 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 wt.% or less of the second plastic waste stream 122, or any range or number therein). The skilled person will appreciate that a particular level of contamination may be based on a particular threshold for a given application. With respect to applications of recycled polyethylene, gel number and black specks targets may be used to determine quality of a final product. To illustrate, ASTM D7310- 11 provides methods and criteria for observing and reporting defects in plastic film using optical scanning. Gels are reported as the total area of defects per total area measured as a total parts per million (ppm) value. The gel content of various size categories is monitored for the detection of step changes in resin quality. For films made from general purpose recycled polyethylene (also referred to herein as “rPE”), total gel counts (all size categories) in excess of 1200 ppm and / or the sum of gel counts (size category in excess of 500 pm) exceeding 200 ppm have been observed to have poor quality. While such observations of poor quality are associated with the mechanically recycled product (e.g., rLLDPE) and not the feedstock, it is demonstrative of the effects of relative feedstock quality on the quality of the resulting mechanically recycled plastic material 152 (and the basis for the particular level of contamination being based on a particular threshold for a given application to produce a recycled product with satisfactory quality).

[0045] In an embodiment, the system 100 of Figure 1 may include at least one pre-wash sorter (not shown in the simplified example depicted in Figure 1) positioned between the first size reduction unit 110 and the washing system 130. The at least one pre-wash sorter may be configured to identify and remove at least a portion of plastic material in the first shredded plastic waste stream 114 that exceeds a maximum contamination level, thereby providing a first sorted shredded plastic stream. In various embodiments, the at least one pre-wash sorter may include at least an optical sorter.

[0046] In various aspects, the system 100 may further include at least one pre-extrusion sorter (not shown in the simplified example depicted in Figure 1) positioned between the second size reduction unit 120 and the extrusion unit 150. Such pre-extrusion sorter(s) may be configured to identify contaminated plastic material (identified in Figure 1 by reference character 128) and uncontaminated plastic material (identified in Figure 1 by the reference character 126) in the second shredded plastic waste stream 124. In one aspect, the system 100 may further include a first conveyor (not shown in the simplified example depicted in Figure 1) that may be operatively connected to such pre-extrusion sorter(s) and configured to transport at least a portion of such contaminated plastic material to (or upstream from) the washing system 130, as identified in Figure 1 by the dashed line adjacent to the reference character 128. The system 100 may further include a second conveyor (not shown in the simplified example depicted in Figure 1) that may be operatively connected to such pre- extrusion sorter(s) and configured to transport such uncontaminated plastic material to the extrusion unit, as identified in Figure 1 by the solid line adjacent to the reference character 126.

[0047] Thus, in some aspects, the system 100 of Figure 1 may include various components (not shown depicted in the simplified example of Figure 1) configured to divert at least a portion of contaminated plastic material that may be identified in the second shredded plastic stream 124 to the washing system 130 for washing (and subsequent drying) prior to such material being fed to the extrusion unit 150. Examples of such components are illustrated and further described herein with respect to Figure 3.

[0048] In other aspects, various methods of mechanically recycling plastic waste (e.g., with the system 100 depicted in the simplified example of Figure 1) are also described herein. According to one aspect, a method of mechanically recycling plastic waste may include utilizing the system 100 of Figure 1 to process the first shredded plastic waste stream 114 and the second shredded plastic waste stream 124 simultaneously to produce the mechanically recycled plastic material 152. According to another aspect, a method of mechanically recycling plastic waste may include utilizing the system 100 of Figure 1 to process the first shredded plastic waste stream 114 and the second shredded plastic waste stream 124 at different times. In such cases, the mechanically recycled plastic material 152 that is produced at one time may be a first product corresponding to a first mechanically recycled plastic material produced from the first shredded plastic waste stream 114, and the mechanically recycled plastic material 152 that is produced at another time may be a second product corresponding to a second mechanically recycled plastic material produced from the second shredded plastic waste stream 124.

[0049] Thus, the system 100 depicted in the simplified example of Figure 1 may be configured to operate in two different wet / dry hybrid recycling configurations. That is, one wet / dry hybrid recycling configuration corresponds to utilizing the system 100 of Figure 1 for simultaneous / parallel processing of both the first and second plastic waste streams 112, 122. Another wet / dry hybrid recycling configuration corresponds to utilizing the system 100 of Figure 1 for processing the first plastic waste stream 112 (e.g., in a “wet” recycling configuration) and the second plastic waste stream 122 (e.g. in a “dry” recycling configuration) at different times. Accordingly, the system 100 of Figure 1 may provide a solution to a variety of the problems / shortcomings associated with existing manufacturing configurations commercially employed in the recycling industry to process recycled polymer feedstocks into a useable pellet form. For example, the system 100 of Figure 1 may potentially allow for improvements in product output, costs, and quality (or any combination thereof) for a given feedstock type.

[0050] Referring to Figure 2, a block diagram depicts an example of a system 200 for mechanically recycling a plastic waste stream, according to a particular embodiment of the present disclosure. In the example depicted in Figure 2, the system 200 includes a first size reduction unit 210, a second size reduction unit 220, a washing system 230, a drying system 240, and an extrusion unit 250. In contrast to the simplified example depicted in Figure 1, Figure 2 represents a first detailed non-limiting example of a hybrid wet / dry mechanical recycling system, according to various aspects of the present disclosure. The system 200 of Figure 2 is also referred to herein as a “Hybrid” configuration, as compared to a “Hybrid Plus” configuration as illustrated and described further herein with respect to Figure 3.

[0051] In various embodiments, the first size reduction unit 210 of the system 200 of Figure 2 may correspond to the first size reduction unit 110 of Figure 1. The first size reduction unit 210 of the system 200 of Figure 2 may be configured to receive and shred a first plastic waste stream 212 to produce a first shredded plastic waste stream 214. Figure 2 illustrates that the system 200 may optionally include a first de-baler 203 that may be positioned upstream of the first size reduction unit 210, according to some aspects of the present disclosure . The first de-baler 203 may be configured to remove wire strapping from bales of feedstock 201 prior to performing mechanical recycling operations, according to some aspects of the present disclosure. The skilled person will be familiar with de-balers and any suitable de-baler may be used for the first de-baler 203. One non -limiting example of such a de-baler is commercially available from Cross Wrap Oy. The skilled person will also recognize that in cases where a de-baler cannot reduce the bale into sizes suitable for the size reduction unit to receive, a bale breaker unit may also be included between the de-baler and the size reduction unit. Additionally, in some cases, de-baling and separation of bale may be done manually. Therefore, the first de-baler 203 is intended to represent any means of making the bale suitable for the first size reduction unit 210 to receive.

[0052] In the particular example depicted in Figure 2, the first size reduction unit 210 may include various components, such as a first shredder 210a that may be configured to cut the first plastic waste stream 212 into pieces. The skilled person will be familiar with shredders for mechanically recycling plastics, and any suitable shredder may be used. One non-limiting example of such a shredder is commercially available from Lindner. Figure 2 further illustrates that, according to some aspects of the present disclosure, the output of the first shredder 210a may correspond to the first shredded plastic waste stream 214 and may be provided to a first separator 211 that may be configured to remove debris, fines, and larger obj ects (with said removed obj ects represented by the reference character 213 adj acent to the arrow pointing down from the first separator 211 in Figure 2). The skilled person will be familiar with such separators, and any suitable separator may be used. Non-limiting examples of such a separator may include a ballistic separator, a vibratory screen, a trommel, or a combination thereof.

[0053] Figure 2 further illustrates that, according to some aspects of the present disclosure, the system 200 may include a pre-wash sorter 215 (or multiple pre-wash sorters) positioned between the first size reduction unit 210 and the washing system 230. The pre-wash sorter 215 may be configured to identify at least a portion of plastic material in the first shredded plastic waste stream 214 that exceeds a threshold contamination level (also referred to herein as “un-washable” material). In various aspects, the pre-wash sorter 215 may include at least an optical sorter that may be configured to separate contaminated material based on optics and near infrared (NIR) analysis. The skilled person will be familiar with optical sorters, and any suitable optical sorter may be used. Non-limiting examples of such optical sorters include those commercially available from suppliers Pellenc and / or Tomra. The pre-wash sorter 215 may be further configured to remove the “un-washable” material identified in the first shredded plastic waste stream 214. Such “un-washable” material is represented in Figure 2 by the reference character 217, and the removal of such material is represented by an arrow pointing down from the pre-wash sorter 215.

[0054] Thus, the pre-wash sorter 215 of the system 200 of Figure 2 may be configured to identify “un-washable” material in the first shredded plastic waste stream 214 and to remove such material as “true waste,” thereby providing a first sorted shredded plastic stream (identified by the reference character 216 in Figure 2). While not shown in the example depicted in Figure 2, according to one embodiment of the present disclosure, the system 200 may further include: a first conveyor operatively connected to the pre-wash sorter 215 and configured to transport the first sorted shredded plastic stream 216 from the pre-wash sorter 215 to the washing system 230; and a second conveyor operatively connected to the pre-wash sorter 215 and configured to transport the “un-washable” material from the pre-wash sorter 215 to a waste unit. In a particular embodiment, the system 200 may further include a controller (not shown in Figure 2) configured to control operation of the first conveyor, the second conveyor, or a combination thereof.

[0055] Figure 2 further illustrates that, according to some aspects of the present disclosure, the first sorted shredded plastic stream 216 may (optionally) be provided to a second shredder 210b that may be configured to further reduce size through a cutting operation. In some aspects, the second shredder 210b may substantially similar to the first shredder 210a or may be an alternative shredder suitable for mechanically recycling plastics. Figure 2 illustrates that an output of the second shredder 210b (identified by the reference character 218) may be provided to the washing system 230 of Figure 2.

[0056] In various embodiments, the washing system 230 of the system 200 of Figure 2 may correspond to the washing system 130 of Figure 1. In contrast to the simplified example depicted in Figure 1, Figure 2 depicts an illustrative, non-limiting example in which the washing system 230 includes multiple components. Figure 2 is designed to illustrate that the washing system 230 is operatively connected to and positioned downstream from the first size reduction unit 210. The various components of the washing system 230 of the system 200 depicted in the example of Figure 2 may be configured to receive and wash a shredded plastic waste stream to produce a washed plastic material stream 232.

[0057] According to various aspects of the present disclosure, Figure 2 illustrates that the washing system 230 may include: a sink float separator or a pre-wash unit (230a); a wet granulator (230b); a friction washer (230c); a hot washer (230d); a sink float tank (230e); or any combination thereof.

[0058] Referring to the particular example depicted in Figure 2, the sink float separator 230a of the washing system 230 may be configured to wash the shredded plastic waste stream that is output by the second shredder 210b (identified by the reference character 218) in order to separate solids, dirt, and plastics heavier than water. The skilled person will be familiar with sink float separators, and any suitable sink float separator may be used. Non-limiting examples of such optical sorters include the Lindner Rafter unit (Lindner) or others commercially available from suppliers such as Herbold or AMUT.

[0059] As illustrated in the example of Figure 2, the wet granulator 230b of the washing system 230 may be operatively connected to and downstream of the sink float separator 230a. The wet granulator 230b may be configured to further reduce the size of material. The skilled person will be familiar with wet granulators, and any suitable wet granulator may be used. Non-limiting examples of such wet granulators include those commercially available from suppliers such as Herbold or Lindner.

[0060] As illustrated in the example of Figure 2, the friction washer 230c of the washing system 230 may be operatively connected to and downstream of the wet granulator 230b. The friction washer 230c may be configured to wash material through friction. The skilled person will be familiar with friction washers, and any suitable friction washer may be used. Non- limiting examples of such friction washers include those commercially available from suppliers such as Herbold or Lindner.

[0061] As illustrated in the example of Figure 2, the hot washer 23 Od of the washing system 230 may be operatively connected to and downstream of the friction washer 230c. The hot washer 23 Od (optional) may be configured to utilize hot water and chemicals to further remove dirt. The skilled person will be familiar with hot washers, and any suitable hot washer may be used. Non-limiting examples of such hot washers include those commercially available from manufacturers such as Herbold or Lindner.

[0062] As illustrated in the example of Figure 2, the sink float tank 23 Oe of the washing system 230 may be operatively connected to and downstream of the (optional) hot washer 230d. The sink float tank 230e may be configured to separate polymer and contaminants by their density in a water bath. The skilled person will be familiar with sink float tanks, and any suitable sink float tank may be used.

[0063] In various embodiments, the drying system 240 of the system 200 of Figure 2 may correspond to the drying system 140 of the system 100 depicted in the simplified example of Figure 1. Figure 2 is designed to illustrate that the drying system 240 is operatively connected to and positioned downstream from the washing system 230 (e.g., downstream of the sink float tank 230e in the particular example depicted in Figure 2). The drying system 240 may be configured to receive and dry the washed plastic material stream 232 to provide a dried plastic material stream 242. The skilled person will be familiar with drying systems and any suitable drying system may be used. Non-limiting examples of drying systems include a dryer, such as a turbo dryer, a thermal dryer, a screw press plastocompactor, or any combination thereof.

[0064] Referring back to the top left portion of Figure 2, the second size reduction unit 220 of the system 200 of Figure 2 may correspond to the second size reduction unit 120 of the system 100 depicted in the simplified example of Figure 1, in various embodiments. The second size reduction unit 220 of the system 200 of Figure 2 may be configured to receive and shred a second plastic waste stream 222 to produce a second shredded plastic waste stream 224. Figure 2 illustrates that the system 200 may optionally include a second de-baler 207 that may be positioned upstream of the second size reduction unit 220, according to some aspects of the present disclosure. The second de-baler 207 may be configured to remove wire strapping from bales of feedstock 205 prior to performing mechanical recycling operations, according to some aspects of the present disclosure. The skilled person will be familiar with de-balers and any suitable de-baler may be used for the second de-baler 207. One non- limiting example of such a de-baler is commercially available from Cross Wrap Oy. As disclosed elsewhere herein, a bale breaker unit may also be included between the second debaler 207 and the second size reduction unit 220, and de-bailing may be a manual process.

[0065] In the particular example depicted in Figure 2, the second size reduction unit 220 may include various components, such as a shredder 220a (e.g., a single shredder, in contrast to the multiple shredders 210a, 210b associated with the first size reduction unit 210) that may be configured to cut the second plastic waste stream 222 into pieces. The skilled person will be familiar with shredders for mechanically recycling plastics, and any suitable shredder may be used. One non-limiting example of such a shredder is commercially available from Lindner.

[0066] Figure 2 further illustrates that, according to some aspects of the present disclosure, the output of the shredder 220a may correspond to the second shredded plastic waste stream 224 and may be provided to a second separator 221 that may be configured to remove debris, fines, and larger objects (with said removed objects represented by the reference character 223 adjacent to the arrow pointing down from the second separator 221 in Figure 2). The skilled person will be familiar with such separators, and any suitable separator may be used. Non-limiting examples of such a separator may include a ballistic separator, a vibratory screen, a trommel, or a combination thereof. Figure 2 illustrates that an output of the second separator 221 (identified by the reference character 226) may be provided (e.g., via a conveyor 227) downstream of the drying system 240 and upstream of the extrusion unit 250 of Figure 2.

[0067] In various embodiments, the extrusion unit 250 of the system 200 of Figure 2 may correspond to the extrusion unit 150 of the system 100 depicted in the simplified example of Figure 1. Figure 2 is designed to illustrate that the extrusion unit 250 is operatively connected to and positioned downstream from the drying system 240 (as well as the conveyor 227 configured to transport the output 226 of the second separator 221). Various components of the extrusion unit 250 of the system 200 depicted in the example of Figure 2 may include components associated with extrusion, melt filtration, vacuum degassing, and pelletization (among other possibilities). The extrusion unit 250 may be configured to melt, filter, and pelletize the received plastic material (including material from the “wet line” in the form of the dried plastic material stream 242 and / or the output 226 conveyed from the “dry line” either simultaneously or at different times, as described further herein) to produce a mechanically recycled plastic product 252 as pellets. The skilled person will be familiar with extrusion units, and any suitable extrusion unit may be used. Non-limiting examples of such extrusion units include those commercially available from manufacturers such as Erema or Starlinger.

[0068] In the example depicted in Figure 2, the system 200 also includes a devolatilization unit 260 (optional) that may be configured to remove volatile compounds that may cause odor by blowing hot air over the pellets (i.e., the mechanically recycled plastic product 252). The skilled person will be familiar with devolatilization units, and any suitable devolatilization unit may be used. Non-limiting examples of such devolatilization units include those commercially available from manufacturers such as Erema or Starlinger. In the example depicted in Figure 2, the system 200 also includes silo storage 262. While not shown in the example of Figure 2, the pellets (i.e., the mechanically recycled plastic product 252) may be homogenized and then conveyed to the silo storage 262 before being sent to packaging.

[0069] In some aspects, the system 200 of Figure 2 may be utilized to mechanically recycle plastic waste by simultaneously processing the shredded plastic waste streams received from the “wet” and “dry” lines to produce the mechanically recycled plastic material 252. In other aspects, the system 200 of Figure 2 may be utilized to mechanically recycle plastic waste by processing, at different times, the shredded plastic waste streams received from the “wet” and “dry” lines to produce the mechanically recycled plastic material 252.

[0070] Thus, the system 200 depicted in the example of Figure 2 (representing a “Hybrid” system configuration, in contrast to the “Hybrid Plus” configuration of Figure 3 described below) may be configured to operate in two different wet / dry hybrid recycling configurations. That is, one wet / dry hybrid recycling configuration corresponds to utilizing the system 200 of Figure 1 for simultaneous / parallel processing of both the first and second plastic waste streams 212, 222. Another wet / dry hybrid recycling configuration corresponds to utilizing the system 200 of Figure 2 for processing the first plastic waste stream 212 (e.g., in a “wet” recycling configuration) and the second plastic waste stream 222 (e.g. in a “dry” recycling configuration) at different times. Accordingly, the system 200 of Figure 2 may provide a solution to a variety of the problems / shortcomings associated with existing manufacturing configurations commercially employed in the recycling industry to process recycled polymer feedstocks into a useable pellet form. Generally, the system 200 of Figure 2 may potentially allow for improvements in product output, costs, and quality (or any combination thereof) for a given feedstock type. More specifically, the system 200 of Figure 2 may combine the benefits of “dry” and “wet” recycling configurations that would normally be associated with such configurations being operated independently (e.g., in different types of recycling facilities). Further, the system 200 of Figure 2 may be able to operate both in “wet” and “dry” modes simultaneously over a wide range of feed ratios. The system 200 of Figure 2 also represents a relatively simple design with a relatively low level of monetary investment. Additional benefits associated with the system 200 of Figure 2 include longer stable runs, substantially uniform product, the ability to operate with a reduced amount of premium (also referred to as “high quality”) feedstock supply, and reduced inventory management complexity. One potential drawback associated with the system 200 of Figure 2 (the “Hybrid” configuration) relative to design described herein with respect to Figure 3 (the “Hybrid Plus” configuration) is an increased potential for the mechanically recycled product being “off grade” in the event that there is unexpected contamination in the premium feedstock.

[0071] Referring to Figure 3, a block diagram depicts an example of a system 300 for mechanically recycling a plastic waste stream, according to a particular embodiment. In the example depicted in Figure 3, the system 300 includes a first size reduction unit 310, a second size reduction unit 320, a washing system 330, a drying system 340, and an extrusion unit 350. In contrast to the simplified example depicted in Figure 1, Figure 3 represents a second detailed non-limiting example of a hybrid wet / dry mechanical recycling system, according to various aspects of the present disclosure. The system 300 of Figure 3 is also referred to herein as a “Hybrid Plus” configuration, as compared to the “Hybrid” configuration illustrated and previously described herein with respect to Figure 2.

[0072] In various embodiments, the second size reduction unit 320 of the system 300 of Figure 3 may correspond to the second size reduction unit 120 of the system 100 depicted in the simplified example of Figure 1, in various embodiments. The second size reduction unit 320 of the system 300 of Figure 3 may be configured to receive and shred a second plastic waste stream 322 to produce a second shredded plastic waste stream 324. Figure 3 illustrates that the system 300 may optionally include a second de-baler 307 that may be positioned upstream of the second size reduction unit 320, according to some aspects of the present disclosure. The second de-baler 307 may be configured to remove wire strapping from bales of feedstock 305 prior to performing mechanical recycling operations, according to some aspects of the present disclosure. The skilled person will be familiar with de-balers and any suitable de-baler may be used for the second de-baler 307. One non-limiting example of such a de-baler is commercially available from Cross Wrap Oy. As disclosed elsewhere herein, a bale breaker unit may also be included between the second de-baler 307 and the second size reduction unit 320, and de-bailing may be a manual process. In the particular example depicted in Figure 3, the second size reduction unit 320 may include various components, such as a shredder 320a (e.g., a single shredder) that may be configured to cut the second plastic waste stream 322 into pieces. The skilled person will be familiar with shredders for mechanically recycling plastics, and any suitable shredder may be used. One non-limiting example of such a shredder is commercially available from Lindner.

[0073] Figure 3 further illustrates that, according to some aspects of the present disclosure, the output of the shredder 320a may correspond to the second shredded plastic waste stream

[0074] 324 and may be provided to a second separator 321 that may be configured to remove debris, fines, and larger objects (with said removed objects represented by the reference character 323 adjacent to the arrow pointing down from the second separator 321 in Figure 3). The skilled person will be familiar with such separators, and any suitable separator may be used. Non-limiting examples of such a separator may include a ballistic separator, a vibratory screen, a trommel, or a combination thereof.

[0075] In contrast to the “Hybrid” configuration illustrated and previously described herein with respect to Figure 2, the system 300 of Figure 3 includes at least one pre-extrusion sorter

[0076] 325 downstream of the second separator 321. Specifically, Figure 3 illustrates that an output of the second separator 321 may be provided to the pre-extrusion sorter 325 (or multiple preextrusion sorters) positioned downstream of the second size reduction unit 320 and upstream of both the washing system 330 and the extrusion unit 350. The pre-extrusion sorter 325 may be configured to identify at least a portion of plastic material in the second shredded plastic waste stream 324 that exceeds a threshold contamination level (also referred to herein as “un- washable” material). In various aspects, the pre-extrusion sorter 325 may include at least an optical sorter that may be configured to separate contaminated material based on optics and NIR analysis. The skilled person will be familiar with optical sorters, and any suitable optical sorter may be used. Non-limiting examples of such optical sorters include those commercially available from suppliers Pellenc and / or Tomra. The pre-extrusion sorter 325 may be further configured to remove the “un-washable” material identified in the second shredded plastic waste stream 324. Such “un-washable” material is represented in Figure 3 by the reference character 319, and the removal of such material is represented by an arrow pointing down from the pre-extrusion sorter 325.

[0077] In further contrast to the “Hybrid” configuration illustrated and previously described herein with respect to Figure 2, the system 300 of Figure 3 includes a holding unit 370 (also referred to herein as a “bunker vessel”) downstream of the pre-extrusion sorter 325. Specifically, Figure 3 illustrates that the holding unit 370 may be configured to act as a buffer in the system 300 by providing enough time for a control valve 372 to react to an unexpected level of contamination detected by the pre-extrusion sorter 325 (with the pre-extrusion sorter 325 and the control valve 372 being communicatively coupled to allow for communication of one or more “diversion” signals, as represented by reference character 374 in Figure 3). With the holding unit 370 acting as the buffer, the control valve 372 may have enough time to switch from a default “do not divert” state to a “divert” state such that contaminated material (identified by the reference character 328 in Figure 3) may be diverted to the “wet” recycling line (e.g., via a conveyor identified by the reference character 329 in Figure 3). Specifically, the holding unit 370 gives time for decision making before the stream goes to the extrusion unit 350 (e.g., via another conveyor identified by the reference character 327 in Figure 3). In this option, the whole stream could be sent to the extrusion unit 350 or diverted to the “wet” recycling line. Sending to the extrusion unit 350 with some contamination may happen, for example, if a determination is made that a mechanically recycled plastic material 352 could be of a different specification and not diverting to the “wet” recycling line for washing may be more cost effective. Alternatively, diverting to the “wet” recycling line may happen, for example, if the specification of the mechanically recycled plastic material 352 cannot be met without washing the contaminated material.

[0078] In various embodiments, the first size reduction unit 310 of the system 300 of Figure 3 may correspond to the first size reduction unit 110 of Figure 1. The first size reduction unit 310 of the system 300 of Figure 3 may be configured to receive and shred a first plastic waste stream 312 to produce a first shredded plastic waste stream 314. Figure 3 illustrates that the system 300 may optionally include a first de-baler 303 that may be positioned upstream of the first size reduction unit 310, according to some aspects of the present disclosure. The first de-baler 303 may be configured to remove wire strapping from bales of feedstock 301 prior to performing mechanical recycling operations, according to some aspects of the present disclosure. The skilled person will be familiar with de-balers and any suitable de-baler may be used for the first de-baler 303. One non-limiting example of such a de-baler is commercially available from Cross Wrap Oy. As disclosed elsewhere herein, a bale breaker unit may also be included between the first de-baler 303 and the first size reduction unit 310, and de-bailing may be a manual process.

[0079] In the particular example depicted in Figure 3, the first size reduction unit 310 may include various components, such as a first shredder 310a that may be configured to cut the first plastic waste stream 312 into pieces. The skilled person will be familiar with shredders for mechanically recycling plastics, and any suitable shredder may be used. One non-limiting example of such a shredder is commercially available from Lindner. Figure 3 further illustrates that, according to some aspects of the present disclosure, the output of the first shredder 310a may correspond to the first shredded plastic waste stream 314 and may be provided to a first separator 311 that may be configured to remove debris, fines, and larger objects (with said removed objects represented by the reference character 313 adjacent to the arrow pointing down from the first separator 311 in Figure 3). The skilled person will be familiar with such separators, and any suitable separator may be used. Non-limiting examples of such a separator may include a ballistic separator, a vibratory screen, a trommel, or a combination thereof.

[0080] Figure 3 further illustrates that, according to some aspects of the present disclosure, the system 300 may include a pre-wash sorter 315 (or multiple pre-wash sorters) positioned between the first size reduction unit 310 and the washing system 330. The pre-wash sorter 315 may be configured to identify at least a portion of plastic material that exceeds a threshold contamination level (also referred to herein as “un-washable” material). In various aspects, the pre-wash sorter 315 may include at least an optical sorter that may be configured to separate contaminated material based on optics and NIR analysis. The skilled person will be familiar with optical sorters, and any suitable optical sorter may be used. Non-limiting examples of such optical sorters include those commercially available from suppliers Pellenc and / or Tomra.

[0081] Figure 3 illustrates that, according to various aspects of the present disclosure, the prewash sorter 315 may be configured to identify at least a portion of plastic material in one or more shredded plastic waste streams that exceeds a threshold contamination level. In some aspects, the pre-wash sorter 315 may be configured to identify at least a portion of plastic material in the first shredded plastic waste stream 314 that exceeds a threshold contamination level. In some aspects, the pre-wash sorter 315 may be configured to identify at least a portion of plastic material in the second shredded plastic waste stream 324 that exceeds a threshold contamination level (diverted to the “wet” recycling line as the contaminated material 328 via the conveyor 329). In some aspects, the pre-wash sorter 315 may be configured to identify at least a portion of plastic material in a combination of two shredded plastic waste streams that exceeds a threshold contamination level, with the two shredded plastic waste streams corresponding to the first shredded plastic waste stream 314 and the diverted contaminated material 328 of the second shredded plastic waste stream 324. Figure 3 further illustrates that the pre-wash sorter 315 may be further configured to remove the “un-washable” material identified in the one or more shredded plastic waste streams 314, 328. Such “un-washable” material is represented in Figure 3 by the reference character 317, and the removal of such material is represented by an arrow pointing down from the pre-wash sorter 315.

[0082] Thus, the pre-wash sorter 315 of the system 300 of Figure 3 may be configured to identify “un-washable” material in the one or more shredded plastic waste streams 314, 328 and to remove such material as “true waste,” thereby providing a first sorted shredded plastic stream (identified by the reference character 316 in Figure 3). While not shown in the example depicted in Figure 3, according to one embodiment of the present disclosure, the system 300 may further include: a first conveyor operatively connected to the pre-wash sorter 315 and configured to transport the first sorted shredded plastic stream 316 from the pre-wash sorter 315 to the washing system 330; and a second conveyor operatively connected to the pre-wash sorter 315 and configured to transport the “un-washable” material from the prewash sorter 315 to a waste unit. In a particular embodiment, the system 300 may further include a controller (not shown in Figure 3) configured to control operation of the first conveyor, the second conveyor, or a combination thereof.

[0083] Figure 3 further illustrates that, according to some aspects of the present disclosure, the first sorted shredded plastic stream 316 may (optionally) be provided to a second shredder 310b that may be configured to further reduce size through a cutting operation. In some aspects, the second shredder 310b may substantially similar to the first shredder 310a or may be an alternative shredder suitable for mechanically recycling plastics. Figure 3 illustrates that an output of the second shredder 310b (identified by the reference character 318) may be provided to the washing system 330 of Figure 3.

[0084] In various embodiments, the washing system 330 of the system 300 of Figure 3 may correspond to the washing system 130 of Figure 1. In contrast to the simplified example depicted in Figure 1, Figure 3 depicts an illustrative, non-limiting example in which the washing system 330 includes multiple components. The various components of the washing system 330 of the system 300 depicted in the example of Figure 3 may be configured to receive and wash one or more shredded plastic waste streams (including at least a shredded plastic waste stream associated with the first size reduction unit 310 and, in some cases, a shredded plastic waste stream associated with the second size reduction unit 320 as described further herein) to produce a washed plastic material stream 332. According to various aspects of the present disclosure, Figure 3 illustrates that the washing system 330 may include: a sink float separator or a pre-wash unit (330a); a wet granulator (330b); a friction washer (330c); a hot washer (330d); a sink float tank (330e); or any combination thereof. In various embodiments, the washing system 230 of the system 200 of Figure 2 may correspond to the washing system 130 of Figure 1. In contrast to the simplified example depicted in Figure 1, Figure 2 depicts an illustrative, non-limiting example in which the washing system 230 includes multiple components.

[0085] Referring to the particular example depicted in Figure 3, the sink float separator 330a of the washing system 330 may be configured to wash the shredded plastic waste stream that is output by the second shredder 310b (identified by the reference character 318) in order to separate solids, dirt, and plastics heavier than water. The skilled person will be familiar with sink float separators, and any suitable sink float separator may be used. Non-limiting examples of such optical sorters include the Lindner Rafter unit (Lindner) or others commercially available from suppliers such as Herbold or AMUT.

[0086] As illustrated in the example of Figure 3, the wet granulator 330b of the washing system 330 may be operatively connected to and downstream of the sink float separator 330a. The wet granulator 330b may be configured to further reduce the size of material. The skilled person will be familiar with wet granulators, and any suitable wet granulator may be used. Non-limiting examples of such wet granulators include those commercially available from suppliers such as Herbold or Lindner.

[0087] As illustrated in the example of Figure 3, the friction washer 330c of the washing system 330 may be operatively connected to and downstream of the wet granulator 330b. The friction washer 330c may be configured to wash material through friction. The skilled person will be familiar with friction washers, and any suitable friction washer may be used. Nonlimiting examples of such friction washers include those commercially available from suppliers such as Herbold or Lindner.

[0088] As illustrated in the example of Figure 3, the hot washer 330d of the washing system 330 may be operatively connected to and downstream of the friction washer 330c. The hot washer 330d (optional) may be configured to utilize hot water and chemicals to further remove dirt. The skilled person will be familiar with hot washers, and any suitable hot washer may be used. Non-limiting examples of such hot washers include those commercially available from manufacturers such as Herbold or Lindner.

[0089] As illustrated in the example of Figure 3, the sink float tank 330e of the washing system 330 may be operatively connected to and downstream of the (optional) hot washer 330d. The sink float tank 330e may be configured to separate polymer and contaminants by their density in a water bath. The skilled person will be familiar with sink float tanks, and any suitable sink float tank may be used. In various embodiments, the drying system 340 of the system 300 of Figure 3 may correspond to the drying system 140 of the system 100 depicted in the simplified example of Figure 1. Figure 3 is designed to illustrate that the drying system 340 is operatively connected to and positioned downstream from the washing system 330 (e.g., downstream of the sink float tank 330e in the particular example depicted in Figure 3). The drying system 340 may be configured to receive and dry the washed plastic material stream 332 to provide a dried plastic material stream 342. The skilled person will be familiar with drying systems and any suitable drying system may be used. Non-limiting examples of drying systems include a dryer, such as a turbo dryer, a thermal dryer, a screw press plastocompactor, or any combination thereof.

[0090] In various embodiments, the extrusion unit 350 of the system 300 of Figure 3 may correspond to the extrusion unit 150 of the system 100 depicted in the simplified example of Figure 1. Figure 3 is designed to illustrate that the extrusion unit 350 is operatively connected to and positioned downstream from the drying system 340 (as well as the conveyor 327 configured to transport the output 326). Various components of the extrusion unit 350 of the system 300 depicted in the example of Figure 3 may include components associated with extrusion, melt filtration, vacuum degassing, and pelletization (among other possibilities). The extrusion unit 350 may be configured to melt, filter, and pelletize the received plastic material (including material from the “wet line” in the form of the dried plastic material stream 342 and / or the output 326 conveyed from the “dry line” either simultaneously or at different times, as described further herein) to produce a mechanically recycled plastic product 352 as pellets. The skilled person will be familiar with extrusion units, and any suitable extrusion unit may be used. Non-limiting examples of such extrusion units include those commercially available from manufacturers such as Erema or Starlinger.

[0091] In the example depicted in Figure 3, the system 300 also includes a devolatilization unit 360 (optional) that may be configured to remove volatile compounds that may cause odor by blowing hot air over the pellets (i.e., the mechanically recycled plastic product 352). The skilled person will be familiar with devolatilization units, and any suitable devolatilization unit may be used. Non-limiting examples of such devolatilization units include those commercially available from manufacturers such as Erema or Starlinger. In the example depicted in Figure 3, the system 300 also includes silo storage 362. While not shown in the example of Figure 3, the pellets (i.e., the mechanically recycled plastic product 352) may be homogenized and then conveyed to the silo storage 362 before being sent to packaging. In some aspects, the system 300 of Figure 3 may be utilized to mechanically recycle plastic waste by simultaneously processing the shredded plastic waste streams received from the “wet” and “dry” lines to produce the mechanically recycled plastic material 352. In other aspects, the system 300 of Figure 3 may be utilized to mechanically recycle plastic waste by processing, at different times, the shredded plastic waste streams received from the “wet” and “dry” lines to produce the mechanically recycled plastic material 352.

[0092] Thus, the system 300 depicted in the example of Figure 3 (representing a “Hybrid Plus” configuration) may be configured to operate in two different wet / dry hybrid recycling configurations. That is, one wet / dry hybrid recycling configuration corresponds to utilizing the system 300 of Figure 3 for simultaneous / parallel processing of both the first and second plastic waste streams 312, 322. Another wet / dry hybrid recycling configuration corresponds to utilizing the system 300 of Figure 3 for processing the first plastic waste stream 312 (e.g., in a “wet” recycling configuration) and the second plastic waste stream 322 (e.g. in a “dry” recycling configuration) at different times. Accordingly, the system 300 of Figure 3 may provide a solution to a variety of the problems / shortcomings associated with existing manufacturing configurations commercially employed in the recycling industry to process recycled polymer feedstocks into a useable pellet form. The system 300 of Figure 3 may provide the aforementioned benefits associated with the “Hybrid” configuration of Figure 2. Additionally, the pre-extrusion optical sorting and bunker may provide additional time to detect unexpected contamination and decide how to handle the unexpected contamination. Further, the configuration of Figure 3 may have less stringent feedstock limitations and / or may have reduced off-grade risk.

[0093] Referring to Figure 4, a flow diagram 400 illustrates an example of a method of mechanically recycling plastic waste, according to various aspects of a present disclosure. The method depicted in Figure 4 may correspond to a scenario in which first and second shredded plastic waste streams are processed at different times such that a first product is produced that comprises a first mechanically recycled plastic material and a second product is produced that comprises a second mechanically recycled plastic material.

[0094] At 410, Figure 4 illustrates that the method may include subjecting a first plastic waste stream to a first size reduction unit to obtain the first shredded plastic waste stream. For example, referring to Figure 1, the method may include subjecting the first plastic waste stream 112 to the first size reduction unit 110 to obtain the first shredded plastic waste stream 114. At 412, Figure 4 illustrates that the method may include subjecting a second plastic waste stream to a second size reduction unit to obtain a second shredded plastic waste stream. For example, referring to Figure 1, the method may include subjecting the second plastic waste stream 122 to the second size reduction unit 120 to obtain the second shredded plastic waste stream 124.

[0095] At 414, Figure 4 illustrates that the method may include identifying contaminated plastic material in the second shredded plastic waste stream and diverting at least a portion of the contaminated plastic material, according to some aspects of the present disclosure. For example, referring to Figure 1, the method may include identifying contaminated plastic material in the second shredded plastic waste stream 124 and diverting at least a portion of the contaminated plastic material (e.g., to or upstream of the washing system 130).

[0096] At 420, Figure 4 illustrates that the method may include subjecting a particular shredded plastic waste steam to a washing system to obtain a washed plastic material stream. For example, referring to Figure 1, the method may include subjecting the first shredded plastic waste steam 114 to the washing system 130 to obtain the washed plastic material stream 132. As another example, referring to Figure 1, contaminated plastic material may be identified in the second shredded plastic material stream 124 at 414, and the method may include diverting at least a portion of the contaminated plastic material (identified by reference character 128 in Figure 1) to subject the diverted contaminated plastic material to the washing system 130 to obtain the washed plastic material stream 132.

[0097] At 430, Figure 4 illustrates that the method may include subjecting the washed plastic material stream to a drying system to obtain a dried plastic material stream. For example, referring to Figure 1, the method may include subjecting the washed plastic material stream 132 to the drying system 140 to obtain the dried plastic material stream 142.

[0098] At 440, Figure 4 illustrates that the method may include providing the dried plastic material stream to an extrusion unit. For example, referring to Figure 1, the extrusion unit 150 may be configured to melt and extrude one or more shredded plastic material streams, and the method may include providing the dried plastic material stream 142 to the extrusion unit 150.

[0099] At 450, Figure 4 illustrates that the method may include subjecting the dried plastic material stream to the extrusion unit to obtain a first mechanically recycled plastic material. For example, referring to Figure 1, the dried plastic material stream 142 may correspond to the first shredded plastic waste stream 114 that has been washed by the washing system 130 to produce the washed plastic material stream 132 and subjected to the drying system 140 prior to subjecting the dried plastic material stream 142 to the extrusion unit 150 to produce the mechanically recycled plastic material 152 (at a particular time). As another example, referring to Figure 1, the dried plastic material stream 142 may correspond to the diverted portion (represented by reference character 128) of the second shredded plastic waste stream 124 that has been washed by the washing system 130 to produce the washed plastic material stream 132 and subjected to the drying system 140 prior to subjecting the dried plastic material stream 142 to the extrusion unit 150 to produce the mechanically recycled plastic material 152 (at a different time).

[0100] At 452, Figure 4 illustrates that the method may include subjecting the second shredded plastic waste stream to the extrusion unit to obtain a second mechanically recycled plastic material. For example, referring to Figure 1, the method may include subjecting the second shredded plastic waste stream 126 to the extrusion unit 150 to obtain a second mechanically recycled product.

[0101] Thus, Figure 4 illustrates an example of a method of mechanically recycling plastic waste with the hybrid wet / dry plastic recycling system of the present disclosure. Figure 4 depicts one example in which different shredded plastic waste streams are processed at different times such that different mechanically recycled products are produced.

[0102] Referring to Figure 5, a flow diagram 500 illustrates another example of a method of mechanically recycling plastic waste, according to various aspects of a present disclosure. The method depicted in Figure 5 may correspond to a scenario in which first and second shredded plastic waste streams are processed simultaneously such that a single mechanically recycled plastic material is produced.

[0103] At 510, Figure 5 illustrates that the method may include subjecting a first plastic waste stream to a first size reduction unit to obtain the first shredded plastic waste stream. For example, referring to Figure 1, the method may include subjecting the first plastic waste stream 112 to the first size reduction unit 110 to obtain the first shredded plastic waste stream 114.

[0104] At 512, Figure 5 illustrates that the method may include subjecting a second plastic waste stream to a second size reduction unit to obtain a second shredded plastic waste stream. For example, referring to Figure 1, the method may include subjecting the second plastic waste stream 122 to the second size reduction unit 120 to obtain the second shredded plastic waste stream 124.

[0105] At 514, Figure 5 illustrates that the method may include identifying contaminated plastic material in the second shredded plastic waste stream and diverting at least a portion of the contaminated plastic material, according to some aspects of the present disclosure. For example, referring to Figure 1, the method may include identifying contaminated plastic material in the second shredded plastic waste stream 124 and diverting at least a portion of the contaminated plastic material (e.g., to or upstream of the washing system 130).

[0106] At 520, Figure 5 illustrates that the method may include subjecting (at least) the first shredded plastic waste steam to a washing system to obtain a washed plastic material stream. For example, referring to Figure 1, the method may include subjecting the first shredded plastic waste steam 114 to the washing system 130 to obtain the washed plastic material stream 132. As another example, referring to Figure 1, contaminated plastic material may be identified in the second shredded plastic material stream 124 at 514, and the method may include diverting at least a portion of the contaminated plastic material (identified by reference character 128 in Figure 1) to subject both the diverted contaminated plastic material and the first shredded plastic waste steam 114 to the washing system 130 to obtain the washed plastic material stream 132.

[0107] At 530, Figure 5 illustrates that the method may include subjecting the washed plastic material stream to a drying system to obtain a dried plastic material stream. For example, referring to Figure 1, the method may include subjecting the washed plastic material stream 132 to the drying system 140 to obtain the dried plastic material stream 142.

[0108] At 540, Figure 5 illustrates that the method may include providing the dried plastic material stream to an extrusion unit. For example, referring to Figure 1, the extrusion unit 150 may be configured to melt and extrude one or more shredded plastic material streams, and the method may include providing the dried plastic material stream 142 to the extrusion unit 150.

[0109] At 542, Figure 5 illustrates that the method may include providing the second shredded plastic waste stream to an extrusion unit. For example, referring to Figure 1, the extrusion unit 150 may be configured to melt and extrude one or more shredded plastic material streams, and the method may include providing the second shredded plastic waste stream 126 to the extrusion unit 150.

[0110] At 560, Figure 5 illustrates that the method may include subjecting both the dried plastic material stream and the second shredded plastic waste stream to the extrusion unit to obtain a (single) mechanically recycled plastic material. For example, referring to Figure 1, the dried plastic material stream 142 may correspond to the first shredded plastic waste stream 114 that has been washed by the washing system 130 to produce the washed plastic material stream 132 and subjected to the drying system 140. As another example, referring to Figure 1, the dried plastic material stream 142 may correspond to a combination of the first shredded plastic waste stream 114 and the diverted portion (represented by reference character 128) of the second shredded plastic waste stream 124 that has been washed by the washing system 130 to produce the washed plastic material stream 132. In either case, the method may include simultaneously subjecting both the dried plastic material stream 142 and the second shredded plastic waste stream 126 to the extrusion unit 150 to obtain a (single) mechanically recycled plastic material 152.

[0111] Thus, Figure 5 illustrates another example of a method of mechanically recycling plastic waste with the hybrid wet / dry plastic recycling system of the present disclosure. Figure 5 depicts an example in which different shredded plastic waste streams are processed simultaneously such that a single mechanically recycled product is produced.

[0112] Non-limiting embodiments of the present disclosure include the following:

[0113] Embodiment 1. A system for mechanically recycling a plastic waste stream, the system comprising: (a) a first size reduction unit configured to receive and shred a first plastic waste stream to produce a first shredded plastic waste stream; (b) a second size reduction unit configured to receive and shred a second plastic waste stream to produce a second shredded plastic waste stream; (c) a washing system configured to receive and wash the first shredded plastic waste stream to produce a washed plastic material stream, wherein the washing system is operatively connected to and positioned downstream from the first size reduction unit; (d) a drying system configured to receive and dry the washed plastic material stream to provide a dried plastic material stream, wherein the drying system is positioned downstream from the washing system; and (e) an extrusion unit configured to receive, melt, and extrude one or both of the dried plastic material stream and the second shredded plastic waste stream to produce a mechanically recycled plastic material, wherein the extrusion unit is positioned downstream from the drying system and the second size reduction unit.

[0114] Embodiment 2. The system of Embodiment 1 wherein the first and second plastic waste streams each comprise film plastic.

[0115] Embodiment 3. The system of Embodiment 1 or 2 wherein the first plastic waste stream comprises contaminated plastic material and the second plastic waste stream comprises uncontaminated plastic material.

[0116] Embodiment 4. The system of Embodiment 3 wherein the contaminated plastic material comprises dirt, grit, organic waste, paper, label adhesive, cellulose, nylon, polypropylene, polyethylene terephthalate, metal, or a combination thereof. Embodiment 5. The system of Embodiment 3 or 4 wherein the uncontaminated plastic material comprises less than 10% contamination.

[0117] Embodiment 6. The system of Embodiment 1 further comprising at least one prewash sorter positioned between the first size reduction unit and the washing system, wherein the at least one pre-wash sorter is configured to identify and remove at least a portion of plastic material in the first shredded plastic waste stream that exceeds a threshold contamination level, thereby providing a first sorted shredded plastic stream.

[0118] Embodiment 7. The system of Embodiment 6, further comprising: a first conveyor operatively connected to the at least one pre-wash sorter and configured to transport the first sorted shredded plastic stream from the at least one pre-wash sorter to the washing system; and a second conveyor operatively connected to the at least one pre-wash sorter and configured to transport the at least a portion of plastic material that exceeds the threshold contamination level from the at least one pre-wash sorter to a waste unit.

[0119] Embodiment 8. The system of Embodiment 7 further comprising a controller configured to control operation of the first conveyor, the second conveyor, or a combination thereof.

[0120] Embodiment 9. The system of Embodiment 6, 7, or 8 further comprising at least one pre-extrusion sorter positioned between the second size reduction unit and the extrusion unit, wherein the at least one pre-extrusion sorter is configured to identify contaminated plastic material and uncontaminated plastic material in the second shredded plastic waste stream.

[0121] Embodiment 10. The system of Embodiment 9, further comprising: a first conveyor operatively connected to the at least one pre-extrusion sorter and configured to transport at least a portion of the contaminated plastic material in the second shredded plastic waste stream from the at least one pre-extrusion sorter to or upstream of the at least one pre-wash sorter or the washing system; and a second conveyor operatively connected to the at least one pre-extrusion sorter and configured to transport the uncontaminated plastic material in the second shredded plastic waste stream from the at least one pre-extrusion sorter to the extrusion unit.

[0122] Embodiment 11. The system of Embodiment 10, wherein: when the at least one pre- extrusion sorter identifies contaminated plastic material in the second shredded plastic waste stream, the first conveyor is automatically actuated to transport the contaminated plastic material in the second shredded plastic waste stream to or upstream of the at least one prewash sorter or the washing system, and when the at least one pre-extrusion sorter identifies uncontaminated plastic material in the second shredded plastic waste stream, the second conveyor is automatically actuated to transport the uncontaminated plastic material in the second shredded plastic waste stream to the extrusion unit.

[0123] Embodiment 12. The system of Embodiment 9 further comprising a holding unit positioned between the at least one pre-extrusion sorter and the extrusion unit and configured to receive the second shredded plastic waste stream from the at least one pre-extrusion sorter. The holding unit is operatively connected to the at least one pre-extrusion sorter, a first conveyor, and a second conveyor. The first conveyor is configured to transport the second shredded plastic waste stream from the holding unit to or upstream of the at least one prewash sorter or the washing system . The second conveyor is configured to transport the second shredded plastic waste stream from the holding unit to the extrusion unit.

[0124] Embodiment 13. The system of Embodiment 10, 11, or 12 further comprising a controller configured to control operation of the first conveyor, the second conveyor, or a combination thereof.

[0125] Embodiment 14. The system of any one of Embodiments 6 to 13 wherein the at least one pre-wash sorter includes an optical sorter.

[0126] Embodiment 15. The system of any one of Embodiments 9 to 14 wherein the at least one pre-extrusion sorter includes an optical sorter.

[0127] Embodiment 16. A method of mechanically recycling plastic waste with the system of any one of Embodiments 1 to 15.

[0128] Embodiment 17. The method of Embodiment 16, comprising: subjecting the first plastic waste stream to the first size reduction unit to obtain the first shredded plastic waste stream; subjecting the second plastic waste stream to the second size reduction unit to obtain the second shredded plastic waste stream; subjecting the first shredded plastic waste steam to the washing system to obtain the washed plastic material stream; subjecting the washed plastic material stream to the drying system to obtain the dried plastic material stream; and subjecting the dried plastic material stream to the extrusion unit to obtain a first mechanically recycled plastic material, subjecting the second shredded plastic waste stream to the extrusion unit to obtain a second mechanically recycled plastic material, or a combination thereof.

[0129] Embodiment 18. The method of Embodiment 16 or 17 wherein the first shredded plastic waste stream and the second shredded plastic waste stream are processed simultaneously such that the mechanically recycled product produced comprises the first mechanically recycled plastic material and the second mechanically recycled plastic material.

[0130] Embodiment 19. The method of Embodiment 16 or 17 wherein the first shredded plastic waste stream and the second shredded plastic waste stream are processed at different times such that a first product is produced that comprises the first mechanically recycled plastic material and a second product is produced that comprises the second mechanically recycled plastic material.

[0131] Embodiment 20. The method of any one of Embodiments 16 to 19 further comprising identifying contaminated plastic material in the second shredded plastic waste stream and diverting at least a portion of the contaminated plastic material.

Claims

CLAIMS1. A system for mechanically recycling a plastic waste stream, the system comprising:(a) a first size reduction unit configured to receive and shred a first plastic waste stream to produce a first shredded plastic waste stream;(b) a second size reduction unit configured to receive and shred a second plastic waste stream to produce a second shredded plastic waste stream;(c) a washing system configured to receive and wash the first shredded plastic waste stream to produce a washed plastic material stream, wherein the washing system is operatively connected to and positioned downstream from the first size reduction unit;(d) a drying system configured to receive and dry the washed plastic material stream to provide a dried plastic material stream, wherein the drying system is positioned downstream from the washing system; and(e) an extrusion unit configured to receive, melt, and extrude one or both of the dried plastic material stream and the second shredded plastic waste stream to produce a mechanically recycled plastic material, wherein the extrusion unit is positioned downstream from the drying system and the second size reduction unit.

2. The system of claim 1, wherein the first and second plastic waste streams each comprise film plastic.

3. The system of claim 1 or 2, wherein the first plastic waste stream comprises contaminated plastic material and the second plastic waste stream comprises uncontaminated plastic material.

4. The system of claim 3, wherein the contaminated plastic material comprises dirt, grit, organic waste, paper, label adhesive, cellulose, nylon, polypropylene, polyethylene terephthalate, metal, or a combination thereof.

5. The system of claim 3 or 4, wherein the uncontaminated plastic material comprises less than 10% contamination.

6. The system of claim 1, further comprising at least one pre-wash sorter positioned between the first size reduction unit and the washing system, wherein the at least one prewash sorter is configured to identify and remove at least a portion of plastic material in the first shredded plastic waste stream that exceeds a threshold contamination level, thereby providing a first sorted shredded plastic stream.

7. The system of claim 6. further comprising: a first conveyor operatively connected to the at least one pre-wash sorter and configured to transport the first sorted shredded plastic stream from the at least one pre-wash sorter to the washing system; and a second conveyor operatively connected to the at least one pre-wash sorter and configured to transport the at least a portion of plastic material that exceeds the threshold contamination level from the at least one pre-wash sorter to a waste unit.

8. The system of claim 7, further comprising a controller configured to control operation of the first conveyor, the second conveyor, or a combination thereof.

9. The system of any one of claims 6-8, further comprising at least one pre-extrusion sorter positioned between the second size reduction unit and the extrusion unit, wherein the at least one pre-extrusion sorter is configured to identify contaminated plastic material and uncontaminated plastic material in the second shredded plastic waste stream.

10. The system of claim 9, further comprising: a first conveyor operatively connected to the at least one pre-extrusion sorter and configured to transport at least a portion of the contaminated plastic material in the second shredded plastic waste stream from the at least one pre-extrusion sorter to or upstream of the at least one pre-wash sorter or the washing system; and a second conveyor operatively connected to the at least one pre-extrusion sorter and configured to transport the uncontaminated plastic material in the second shredded plastic waste stream from the at least one pre-extrusion sorter to the extrusion unit.

11. The system of claim 10, wherein: when the at least one pre-extrusion sorter identifies contaminated plastic material in the second shredded plastic waste stream, the first conveyor is automatically actuated to transport the contaminated plastic material in the second shredded plastic waste stream to or upstream of the at least one pre-wash sorter or the washing system, and when the at least one pre-extrusion sorter identifies uncontaminated plastic material in the second shredded plastic waste stream, the second conveyor is automatically actuated to transport the uncontaminated plastic material in the second shredded plastic waste stream to the extrusion unit.

12. The system of claim 9, further comprising a holding unit positioned between the at least one pre-extrusion sorter and the extrusion unit and configured to receive the second shredded plastic waste stream from the at least one pre-extrusion sorter,wherein the holding unit is operatively connected to the at least one pre-extrusion sorter, a first conveyor, and a second conveyor, wherein the first conveyor is configured to transport the second shredded plastic waste stream from the holding unit to or upstream of the at least one pre-wash sorter or the washing system, and wherein the second conveyor is configured to transport the second shredded plastic waste stream from the holding unit to the extrusion unit.

13. The system of any one of claims 10-12, further comprising a controller configured to control operation of the first conveyor, the second conveyor, or a combination thereof.

14. The system of any one of claims 6-13, wherein the at least one pre-wash sorter includes an optical sorter.

15. The system of any one of claims 9-14, wherein the at least one pre-extrusion sorter includes an optical sorter.

16. A method of mechanically recycling plastic waste with the system of any one of claims 1 to 15.

17. The method of claim 16, the method comprising: subjecting the first plastic waste stream to the first size reduction unit to obtain the first shredded plastic waste stream; subjecting the second plastic waste stream to the second size reduction unit to obtain the second shredded plastic waste stream; subjecting the first shredded plastic waste steam to the washing system to obtain the washed plastic material stream; subjecting the washed plastic material stream to the drying system to obtain the dried plastic material stream; and subjecting the dried plastic material stream to the extrusion unit to obtain a first mechanically recycled plastic material, subjecting the second shredded plastic waste stream to the extrusion unit to obtain a second mechanically recycled plastic material, or a combination thereof.

18. The method of claim 16 or 17, wherein the first shredded plastic waste stream and the second shredded plastic waste stream are processed simultaneously such that the mechanically recycled product produced comprises the first mechanically recycled plastic material and the second mechanically recycled plastic material.

19. The method of claim 16 or 17, wherein the first shredded plastic waste stream and the second shredded plastic waste stream are processed at different times such that a first productis produced that comprises the first mechanically recycled plastic material and a second product is produced that comprises the second mechanically recycled plastic material.

20. The method of any one of claims 16-19, further comprising identifying contaminated plastic material in the second shredded plastic waste stream and diverting at least a portion of the contaminated plastic material.

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