WO2019137694A1

WO2019137694A1 - Asphalt composition comprising waste disposable container material such as coffee cups

Info

Publication number: WO2019137694A1
Application number: PCT/EP2018/083341
Authority: WO
Inventors: Glyn Woolley; Edmund Michael REED
Original assignee: Glyn Woolley; Reed Edmund Michael
Priority date: 2018-01-11
Filing date: 2018-12-03
Publication date: 2019-07-18
Also published as: GB201819686D0; GB2577136A

Abstract

A method for manufacturing a composite material comprises adding waste disposable container material to a mixture comprising an asphalt binder and an aggregate or rock/sand mixture.

Description

ASPHALT COMPOSITION COMPRISING WASTE DISPOSABLE CONTAINER MATERIAL SUCH AS COFFEE CUPS

TECHNICAL FIELD

The present invention relates, in general, to composite materials, a method of manufacture thereof and also to road making material.

BACKGROUND

Composite materials, such as asphalt concrete for example, can be used as a surfacing material in many different circumstances and areas, such as roads, parking lots, airports and so on. Asphalt concrete, which is more commonly referred to simply as asphalt or tarmac for example, consists of a mineral aggregate (e.g. stone) that is bound together with asphalt (bitumen). In use, it is deposited in layers, and compacted to form a hard-wearing surface.

SUMMARY

According to an example, there is provided a method for manufacturing a composite material comprising adding waste disposable container material to a mixture comprising an asphalt binder and an aggregate or rock/sand mixture. According to an example, there is provided a method for manufacturing a composite material comprising adding waste disposable beverage container material to a mixture comprising an asphalt binder and an aggregate or rock/sand mixture. The method can further comprise heating the aggregate or rock/sand mixture. For example, the aggregate or rock/sand mixture can be heated to between 100-250 degrees C. The aggregate or rock/sand mixture can be heated to between 120- 190 degrees C. The method can further comprise shredding or forming pellets from the waste disposable container material. The method can further comprise heating the aggregate or rock/sand mixture to a temperature above a melting temperature of a plastics component of the waste disposable container material. The method can further comprise adding cellulose fibre material to the mixture. The container material can be a beverage or foodstuff container material comprising a combination of cellulosic and plastics material. According to an example, there is provided an asphalt concrete composition comprising an aggregate or rock/sand mixture, an asphalt binder, and a waste disposable container material comprising a combination of cellulosic and plastics material. The waste disposable container material can be shredded or in the form of pellets. The asphalt concrete composition can comprise around 0.3% - 1 % w/w waste disposable container material. In an example, the asphalt concrete composition can comprise around 0. 1 % - 5% w/w waste disposable container material. The composition can be a hot mix or warm mix asphalt concrete composition. The i container material can be a beverage or foodstuff container material comprising a combination of cellulosic and plastics material.

According to an example, there is provided a waste disposable container material when used in an asphalt concrete composition, the material comprising a combination of cellulosic and plastics material in a virgin, shredded or pellet form. The container material can be a beverage or foodstuff container material comprising a combination of cellulosic and plastics material.

This invention also relates to a method of producing a road making/ repairing material and to a road made therefrom or repaired therewith.

The present invention provides a road formed from material which includes beverage cup material, or other waste container material.

The term "road" used herein includes within its scope vehicle highways, pedestrian paths (known as pavements, or sidewalks in some countries) or cycle paths.

In some embodiments the road is multi-layered, for example: i) a surface course (or wearing course); ii) a binder course (or base course); and iii) a road base (or base).

The present invention provides for a multi-layered road surface in which at least one of the layers includes waste material.

The present invention provides for a multi-layered road surface in which at least one of the layers includes a waste material which cannot be recycled using normal recycling systems.

The present invention provides for a multi-layered road surface in which at least one of the layers is formed from a material as generally described herein. For example: in some embodiments all layers include the material; in other embodiments only one layer includes composite material; in one embodiment a top surface layer is formed from the composite material; in a further embodiment a binder course and a road base layer include the material.

The amount of container material used to form the composition can vary depending on the intended use. It is noted, for example, that it may be possible for the binder course and road base layers in a road to contain a higher percentage of the recycled material than the surface course, partly due to the level of binding required relative to the bitumen content. In some embodiments the road layer/s include recycled beverage cups, sometimes known as “coffee cups”. These cups are not readily recyclable because they are made from paper/card board with a tightly bonded polyethylene liner, and often have a wax coating. The wax, for example, can be beneficial in certain embodiments, where it can act as a binder improver.

Pellets or other material used in the production of the road layer can have varying levels of beverage container material. In the binder course and road base layers the percentage of material which can be provided by the recycled material (for example beverage container material) can be higher than for the surface course.

Examples of the percentage of recycled material (e.g. beverage container material) present in a raw material used in asphalt production (such as a pellet or the like) include: 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50% or up to 100%.

In some embodiments beverage container material is the sole recycled material present. In other embodiments other material, such as paper, or other water disposable container material may be included. The container material (beverage and/or other) may be virgin or used.

The road layer/s can comprise up to 1 00% beverage container material, for example: 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50% or up to 100%.

In some embodiments an asphalt concrete composition can comprise around 0. 1 % - 10% w/w waste disposable beverage container material. In an example, the asphalt concrete composition can comprise around 0. 1 % - 5% w/w waste disposable beverage container material. The composition can be a hot mix or warm mix asphalt concrete composition.

The present invention also provides a method of producing a road making material including the steps of: i) separately heating aggregate and bitumen; ii) mixing the heated aggregate and bitumen; and iii) adding non-recyclable waste material to the heated mix to produce a bitumen compound.

It may be preferred that no other materials are added to the mix.

The term “non-recyclable” means waste material which cannot be recycled using normal recycling systems. The recycled material may be cleaned and/or shredded and/or heated prior to adding. It may be formed into pellets or the like.

According to an example, there is provided a pelletised additive for use in bituminous asphalt mixtures, the pelletised additive comprising a compressed blend of cellulosic, and polymer materials derived from virgin or non-virgin waste container material. The pelletised additive can further comprise a wax material. The polymer material can be a low-density polyethylene. The container material can be a beverage or foodstuff container material comprising a combination of cellulosic and plastics material.

Different aspects and embodiments can be used together or separately.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure I is a schematic representation of a road structure according to an example;

Figure 2 is a schematic representation of a road structure in which all layers are formed from beverage container composite material, according to an example;

Figure 3 is a schematic representation of a road structure in which the surface course is formed from beverage container composite material, according to an example;

Figure 4 is a flowchart of a method according to an example; and

Figure 5 is a flowchart of a method according to an example.

DESCRIPTION

Example embodiments are described below in sufficient detail to enable those of ordinary skill in the art to embody and implement the systems and processes herein described. It is important to understand that embodiments can be provided in many alternate forms and should not be construed as limited to the examples set forth herein.

Accordingly, while embodiments can be modified in various ways and take on various alternative forms, specific embodiments thereof are shown in the drawings and described in detail below as examples. There is no intent to limit to the particular forms disclosed. On the contrary, all modifications, equivalents, and alternatives falling within the scope of the appended claims should be included. Elements of the example embodiments are consistently denoted by the same reference numerals throughout the drawings and detailed description where appropriate.

The terminology used herein to describe embodiments is not intended to limit the scope. The articles“a,”“an,” and“the” are singular in that they have a single referent, however the use of the singular form in the present document should not preclude the presence of more than one referent. In other words, elements referred to in the singular can number one or more, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes,” and/or “including,” when used herein, specify the presence of stated features, items, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, items, steps, operations, elements, components, and/or groups thereof.

Unless otherwise defined, all terms (including technical and scientific terms) used herein are to be interpreted as is customary in the art. It will be further understood that terms in common usage should also be interpreted as is customary in the relevant art and not in an idealized or overly formal sense unless expressly so defined herein.

An asphalt concrete composite mixture (i.e. a bitumen and aggregate mixture) can deform at high temperatures and/or crack at low temperatures. Such issues can be mitigated by increasing the percentage of bitumen used in the mixture and/or modifying the mixture by using one or more additives to enhance its final properties.

For example, additives, such as polymers or pelletised/shredded cellulosic material (such as paper or cardboard for example), can be used. Polymers, such as Ethylene Vinyl Acetate (EVA) for example, can amplify the binding properties of the bitumen. Other suitable polymers can be used. In cases where more bitumen is used in order to increase binding in the mixture, cellulosic additives can reduce the likelihood of the bitumen draining out of a mixture at high temperatures, such as when it is being deposited, thereby acting as a medium to retain bitumen in the mixture.

One particular composite mixture is stone filled mastic asphalt (SMA) which consists, by weight, of about 4-7% bitumen and about 0.3- 1 % of a modifier such as cellulose fibres that are added to provide stability to the bitumen in the mixture so as to prevent drainage as noted above. The remainder of the mixture comprises an aggregate such as crushed stone or a rock/sand mixture. The process of manufacturing the SMA typically involves heating the aggregate to a high temperature (e.g. 120+ degrees C) which is then passed into a mixer at which point heated bitumen as well as the modifier can be added.

SMA is a product which conforms to a design carried out with a particular aggregate and bitumen source. The typical average bitumen content is around 5.5% but can have a range tolerance of around plus or minus 0.5% or so. Other asphalt products can have target bitumen contents up to around 8.5% or so and down to 3.5% or even less. The average amount of fibre addition in SMA is around 0.3% to 0.5% by weight but will have a range tolerance higher and lower than this.

According to an example, a method for manufacturing a composite material comprises using waste disposable containers, such as beverage or foodstuff (such as takeaway/fast-food for example) containers, cartons, sandwich containers and so on, which have a combination of card/card board and plastic, such as in the form of a "window" through which the contents of the container can be seen, and which could be recycled to provide a combined cellulosic and polymer additive for use in a bitumen/aggregate mixture. Such waste material can wholly or partly replace cellulose fibres used as a binder in such mixtures, and a plastics component that is present in the waste amplifies the binding properties of the bitumen. As such, a readily available cellulosic material can be used, which has the additional benefit of comprising a plastics material that can augment the binding effect of the bitumen.

For example, beverage containers and the like typically comprise an outer layer of paper and/or cardboard, and an inner layer of polymer material forming an impermeable barrier to prevent leakage of any liquid or foodstuff from the container through the paper/card board outer. The impermeable barrier can be in the form of a low-density polyethylene type of plastics material, which has a melting point of between 100 and 200 degrees C, for example N O and 120 degrees C. Similarly, disposable containers for foodstuffs, such as sandwich containers for example, comprise a cellulosic material and a plastics material in the form of a window for example, through which the contents of the container can be seen. Accordingly, such containers comprise a combination of cellulosic and plastics materials. Such materials can be provided by way of reverse vending, in which a consumer, for example, is rewarded for provided a used container for recycling.

In an example, since the melting point of the plastics barrier of the container is lower than the temperature to which an aggregate is heated in an SMA production process, it will melt and form part of the mixture, with the "stringy" nature of the resulting plastics filaments enhancing the performance of the product. Accordingly, the addition of waste container material to a bitumen/aggregate mixture provides both cellulosic and polymer materials to enhance the properties of a resulting structure, providing a cellulosic component to retain bitumen in the mixture and a polymer component to enhance the binding properties of the bitumen in the mixture.

Accordingly, waste beverage (for example) containers comprising a paper/card board element can act as a binder retention medium and the plastics internal liner of the container can also impart beneficial properties to the final mix improving in situ performance. In an example, such waste disposable cups or other such material can be added in any state - either in their virgin condition, shredded or as a pellet or any combination or these states.

In an example, a pelletised additive for use in bituminous asphalt mixtures can be prepared by shredding waste material in order to produce a lightweight voluminous, downy, mass composed of fibres of the container material. That is, a container comprising an outer layer of paper and/or cardboard, and an inner layer of polymer material, and optionally including a wax coating, can be processed by: (optionally) cleaning; (optionally) drying; shredding (such as by feeding the material to be shredded through one or more sets of contra-rotating knife or cutting structures for example) to form the mass of fibrous material; compressing the mass of fibrous material; and extruding the compressed mass of fibrous material through one or more dies of desired cross-section. As part of the extrusion process, the extruded material may be intermittently cut in order to form pellets. Alternatively, the relatively brittle nature of the extruded material may cause the extrusion to crumble or break into pellet sized parts as it passes through the die. As part of the compressing process, the moisture content of the mass of fibrous material can be modified.

Thus, in an example, the shredded material can be formed into pellets by compressing it to form a compressed mass, and extruding the compressed mass through a suitable die to form the pellets. In order to form the compressed mass, the moisture content of the fibrous material may need to be adjusted in order to enable the material to be extruded and for the extruded material to be maintained in pellet form. Recycled material may already be wet (either as a result of cleaning, or because of a residue of other liquids). The moisture content of the fibrous material can be increased by adding water, or decreased by drying. For example, a moisture content of between I -20% by weight can be used. Other materials comprising a paper/cardboard element, a plastics coating, and (optionally) a wax coating can be used. For example, containers used for takeaway foodstuffs are often composed of the same type of materials as beverage containers. Accordingly, such container may also be processed as described above, either in isolation or along with beverage containers, in order to produce a pelletised additive.

According to an example, waste disposable containers can be used in various bituminous asphalt mixtures, and in varying amounts. The waste material can be finely shredded which can improve its handling properties and makes it possible to use existing fibre handling equipment which would exist in most asphalt plants. Waste disposable containers used for hot or cold drinks or foodstuffs, cardboard only, plastics only or composite construction can be used.

In Figure I a road structure is shown. The road is multi-layered: i) a surface course 100 (or wearing course); ii) a binder course 101 (or base course); and iii) a road base 103. Only the binder course 101 and road base 103 are formed from container (beverage or foodstuff) composite material.

In Figure 2 all three layers ( 100, 101 , 103) are formed from container composite material.

In Figure 3 only the surface course ( 100) if formed from container composite material.

Figure 4 is a flowchart of a method according to an example. That is, a container material 400 comprising an outer layer of paper and/or cardboard, and an inner layer of polymer material, and optionally including a wax coating, can be processed to form a pelletised additive 41 I for use in bituminous asphalt mixtures by: optionally cleaning (401 ); optionally drying the cleaned material (403); shredding the material (405); compressing the shredded material (407); and extruding the compressed material (409). In an example, a binding medium can be added to the shredded material pellet. Alternatively, a binding material can be added during or following compression, or during, before or after extrusion. The binding material can help to hold a pellet together. For example, bitumen can be used as an additive, and will help to hold a pellet together whilst it is being transported, stored or handled prior to being added to an asphalt mixture.

Figure 5 is a flowchart of a method according to an example. In the example of figure 5, a method for manufacturing a composite material 507, such as a beverage container composite material for example, comprises adding waste disposable container material 500, such as the pelletised additive described above, to a mixture 501 comprising a binder material 503, such as bitumen, and an aggregate or rock/sand mixture 505. The composite material can be used in the formation of roads and the like, such as those described above with reference to figures I - 3 for example. The present inventions can be embodied in other specific apparatus and/or methods. The described embodiments are to be considered in all respects as illustrative and not restrictive. In particular, the scope of the invention is indicated by the appended claims rather than by the description and figures herein. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

1 . A method for manufacturing a composite material comprising:

adding waste disposable container material to a mixture comprising an asphalt binder and an aggregate or rock/sand mixture.

2. A method for manufacturing a composite material comprising:

adding waste disposable beverage container material to a mixture comprising an asphalt binder and an aggregate or rock/sand mixture.

3. A method as claimed in claim I or 2, further comprising heating the aggregate or rock/sand mixture.

4. A method as claimed in any preceding claim, further comprising:

shredding the waste disposable container material.

5. A method as claimed in any claim, further comprising:

forming pellets from the waste disposable container material.

6. A method as claimed in any preceding claim, further comprising:

heating the aggregate or rock/sand mixture to a temperature above a melting temperature of a plastics component of the waste disposable container material.

7. A method as claimed in any preceding claim, further comprising:

adding cellulose fibre material to the mixture.

8. An asphalt concrete composition comprising:

an aggregate or rock/sand mixture;

an asphalt binder; and

a waste disposable container material comprising a combination of cellulosic and plastics material.

9. An asphalt concrete composition as claimed in claim 8, wherein the waste disposable container material is a beverage or foodstuff container material.

10. An asphalt concrete composition as claimed in claim 8 or 9, wherein the container material is shredded.

1 1 . An asphalt concrete composition as claimed in any of claims 8 to 10, wherein the waste disposable container material is in the form of pellets.

12. An asphalt concrete composition as claimed in any of claims 8 to I I , comprising around 0.3% - 1 % w/w waste disposable container material.

13. An asphalt concrete composition as claimed in any of claims 8 to 1 , wherein the composition is a hot mix or warm mix asphalt concrete composition.

14. A waste disposable container material when used in an asphalt concrete composition, the material comprising a combination of cellulosic and plastics material in a virgin, shredded or pellet form.

15. A method of producing a road making material comprising the steps of adding container material to a mixture comprising an asphalt binder and an aggregate or rock/sand mixture.

16. A method as claimed in claim 15, wherein the container material is a beverage or foodstuff container material comprising a combination of cellulosic and plastics material.

17. A road making material comprising container material.

18. A road making material as claimed in claim 17, comprising asphalt binder and an aggregate or rock/sand mixture.

19. A road making material as claimed in claim 17 or 18, wherein the container material is a beverage or foodstuff container material comprising a combination of cellulosic and plastics material.

20. A road made from the material of one of claims 17 to 19.

2 1 . A road as claimed in one of claims 17 to 20, in which the road is multi-layered.

22. A road as claimed in claim 2 1 , in which the road comprises: i) a surface course (or wearing course); ii) a binder course (or base course); and iii) a road base.

23. A road as claimed in claim 1 or claim 22, in which at least one of the layers comprises container material.

24. A road as claimed in claim 23, wherein the container material is a beverage or foodstuff container material comprising a combination of cellulosic and plastics material.

25. A road as claimed in claim 2 1 or 24, in which only the binder course and road base layers comprise container material.

26. A pelletised additive for use in bituminous asphalt mixtures, the pelletised additive comprising:

a compressed blend of cellulosic, and polymer materials derived from virgin or non virgin waste container material.

27. The pelletised additive as claimed in claim 2 1 , further comprising a wax material.

28. The pelletised additive as claimed in claim 2 1 or 22, wherein the polymer material is a low-density polyethylene.

29. The pelletised additive as claimed in claim 26 to 28, wherein the container material is a beverage or foodstuff container material comprising a combination of cellulosic and plastics material.