What is foil?
Foil, as it’s called in this article, refers to a flexible packaging material. Formally a packaging material is being seen as flexible when it has a thickness of maximum 250 micron. De choice of the material depends on the application of the material, the demands of the customer and sometimes even the production possibilities of the producer. For years the packaging materials have been optimized, as a result there are infinite variations. All these variations make recycling a big challenge, and we understand that there are uncertainties if the packaging material the customer uses can be recycled or not.
In theory almost all plastics can be recycled independently. However we try to make a distinction between 2 kinds:
- Foils that are average to good mechanically recyclable.
- Foils that are limited to not mechanically recyclable.
The recyclability of the material is not the only condition which determines if the foil in the end will be recycled. This is because there are a variety of other factors that can make recycling even more challenging. Examples of factors which can make recycling more challenging are; pollution degree, the size of the material, any printing on the material, the presence of additives (calcium, coloring, fire prevention, etc.) and the presence of stickers, tape or labels etc. Lastly, there is one important condition which is that the recycling-infrastructure must be designed on the specific material. If the specific material is not separated from the larger mix of materials, or if the process is too expensive or too complicated, than there is a chance that the material is still being dumped or burned and not recycled.
Foils that are average to good mechanically recycable
These are foils with simple construction (mono-materials) specifically foils that are made of plastics that are part of the polyolefin groups, like Polyethylene in different densities (LLDPE, LDPE, MDPE and HDPE) and Polypropylene (However, PP is less optimal recyclable than PE).
Foils that are limited to not mechanically recycable
Mono-materials which are made of other plastics like PET, PS, PVC or PA are at the moment not successfully recyclable. The same applies for multiple-layer packaging material which are made of different materials which for instance are laminated together. An example of that would be chips bags which are often made of PP with aluminum, or bakeoff-rolls which are packed in a combination of flexible tray with cover foil were the materials PET, PE, PVC, PA and EVOH are all used together in one single packaging. Because the packaging is not made out of 1 single pure packaging material, it is difficult for the sorting equipment or sorting employees to effectively separate all the different kinds of plastic. If the materials are being melted together, the quality of the recycled product goes down. Separating materials that are for instance laminated together is therefore not economically profitable or even technically too complicated.
Of course technological advancements in time can make that more packaging materials can be better recycled for less costs. However, if you want to design more circular packaging at this moment, than the advice is to use the material Polyethylene.
Keep in mind that you always have to deal with the environmental-impact of the total life cycle of the material. For instance if with the material PE to much is handed in, for instance in the duration and the protection of the product, than more circularity does not necessarily mean it is more sustainable.
Other factors that determine if foil can be successfully recycled
If you have a packaging material that is completely (or largely) made out of PE, that does not mean it is naturally good recyclable.
The recycling check of flexible packaging material of the KIDV makes a distinction between good recyclable, reasonably recyclable, limitedly recyclable and not preferably or not recyclable. The decision tree looks at the collection, the interference substances, the obstruction of sorting and the obstruction during the recycling process. What the recycling check misses but what is in practice very important, is the type of contamination or the extend of the contamination in the material.
In short it comes to the fact that packaging materials are only good recyclable if its pure PE packaging, its bigger than A4-size and if the material is clear from impurities like labels, non-washable glue, additives (like barriers and coatings) and metal parts. In principle any additive adds a possible extra obstruction for recycling. In practice there is almost always one or more additives in a material. The most frequent additives like labels and stickers are often added later in the supply chain (for instance in the store). That makes the packaging material already less recyclable, or the end result of the recycled product of less high quality.
Collection and interference substances
According to the recycling check, nets (e.g. for oranges and unions), packaging of medicines and packaging from small chemical waste belong to residual waste. These packaging will not be treated like plastic and will therefore not be recycled as plastics. Furthermore, the material must first be free of interference substances, like Oxo-degradable material, PVC, silicones and other non-plastic materials, to be recycled.
Barriers while sorting and recycling
The steps in the mechanical recycling process of flexible packaging mostly consists of; sorting (automatically of manually), grind/shred, wash, separate, dry, melt, granulate and cool off and dry again.
The measurements of the waste is a particularly important factor in the sorting process. The smaller the waste, the more difficult it gets to recognize the right waste during the sorting process. This is why the a4-measurement is the standard in the recycling process.
Additives in the foil can worsen the conditions of the recycled product in numerous ways. For example, sorting installations can sometimes not pick out black pigments, as a result the black pigments find their way into the mix fraction. When adding for instance Calcium Carbonate (a frequently used filler fluid) has an added effect that the weight of the material will increase. PE is usually lighter than water, as such the much used float-sink separation process will separate heavier materials (such as PA and PVC). When the PE is heavier because of filler fluids than it is separated together with the heavier materials and will go the residual waste pile. Lastly, any other additives (EVOH or flame retardant additives) can have a negative effect of the recycled material.
Traces of (paper) labels, stickers and glue residues often remain during the recycling process, this has a negative effect on the quality of the recycled product, the recycling process and the extrusion process.
Metal parts such as staples can cause that the whole packaging can end up on the residual pile during the metal detection process. However, metal parts do find their way through further steps in the recycling process, and there it also cause problems. Problems such as, wear, blockage of knives, screws and filters and even the complete stop of the line because of metal detection.
Despite the fact that with cold or hot washing a large portion of the plastic can be thoroughly cleaned, in practice much of the waste will not be accepted and finds it way, despite the material, to the burning oven. For example:
- Difficult to wash, greased-up waste like oils, mayonnaise and butter.
- Food waste that bare the risk of bacteria growth, yeasts and pests are also not desirable.
- Foils without excessive food waste, but which have a strong scent (like fish packaging) will also not be accepted by processors.
- Even if there is not excessive amount of non-food material waste on the packaging, it can lead to problems during or after the recycling process.
Why is mechanical recycling important?
The most important added value can be summarized as followed:
- It contributies to less litter
- By keep re-using materials we use up less fossil fuels, which contributes to a clean environment.
- In addition mechanical recycling has a lower carbon-footprint than producing new polymers, or the alternative process of chemical recycling.
- Lastly, you mechanical recycle materials it can eventually also be chemically recycled or be used a fuel for energy recovery. This way you get the most out of the material.
There are some important sidenotes:
Because the fact is that Recycling does not stand for completely circular. Flexible (food) plastics cannot be re-used again in new food packaging after it has been recycled. This regarding the food safety. However, recycled plastics also have their limitations. Furthermore, packaging that have coloring on them, or have been printed on can only be recycled as ‘variegated’ granulates. The application possibilities of those granulates are much more limited, this is also called; downcycling. It is a challenge to downcycle as little as possible. This can only be achieved when the waste flows are as pure, clean and separated as possible. The start of closed loops can contribute to this.
The challenges and possibilities differentiate in every region. The waste collection structure and the available recycling technology can be different in each country, and even in each region. Packaging waste that corporations make (often secondary waste/nonfood waste), like retail or production companies are often less contaminated and better separated. The recycling percentage for corporations are often one-third of the total plastic packaging waste, and is significantly better than what the statistics show. Because everything is so much bigger the challenges are smaller and the possibilities bigger. With packaging that are often collected as waste on the residual pile, it is more complex to determine which changes will be effective. Besides calling in a packaging expert, it can also help to call in household waste company’s like Attero or GP Groot, or even scientists like the scientists of Wageningen University & Research with their extensive knowledge of waste and materials.
There are continuate technological advancements (like de-inking, de-smelling etc) and the sales market is constantly moving. The possibilities for recycling are therefor in a constant development. As a result certain insights of this report can soon be out of date.
Design for recycling must not be an objective per se. If you change the packaging of a product from laminate to PE, but you have to give in on protection of the product, than you must do a research if in the end you improved your environmental footprint or not.
Design for recycling is not the same as using recycled plastics in your new plastics. When more and more packaging materials can be recycled, but the market for recycled products falls behind, than still a fraction of the amount that can be recycled, will be recycled. With food packaging the implication of recycled products can be difficult, however there are numerous applications in which recycled materials can be used. On one hand this takes the attention of processors, but on the other hand it also have to take a lot of economical stimulus. As long as the costs of primary raw material competes with secondary raw material, the market of secondary raw material will always stay behind.
Replacing laminates by recycable foils
For a large number of packaging application we see that laminates can easily be replaced by non-laminated PE, which is easily recyclable. An example of this is packaging for products that go in the freezer, for instance vegetables, fruits and chips. Our special (FFS foil) PE-foil with extra firmness can create for the desired firmness of the packaging, without taking any concessions to the protection or shelf life of the product. At this stage we even can deliver a foil in a variant that can cause no problems and modifications to original heat seal systems.
Curious about the possibilities of making your foil recyclable?
Please contact one of our experienced employees using the contact form below. You will get a response as soon as possible