Plastic is a material that is incorporated into an enormous array of products. Consequently, global plastic production—and the associated amount of plastic waste—are staggering. What happens to all this waste? Only about 9% of it is recycled. In this article, you'll discover everything about plastic recycling. What methods of recycling exist, what are their pros and cons, and what can we say about recycling from a sustainability perspective?
What happens to plastic waste?
Global plastic production is enormous, and so is the amount of plastic waste: each year, this amounts to 350 million tons of plastic waste worldwide. That's 350,000,000,000 kg, or 350 with nine zeros. This is equivalent to the weight of 1.75 million blue whales; the heaviest animals on earth.
Of this immense amount of plastic waste, only about 9% is recycled. The rest is processed like non-recyclable waste and ends up in landfills, incinerators, or the natural environment.
Plastic exposed to the open air disintegrates into microplastics due to weather conditions; these are tiny plastic particles. These microplastics have various negative effects on nature and harm the health of humans and animals. Learn more about this in our article Plastic & Sustainability: Everything You Want to Know.
Is plastic waste really exported abroad?
You might have heard that Dutch plastic waste is shipped abroad. Unfortunately, this is not just an urban myth. In fact, in 2021, the Netherlands was the largest exporter of plastic waste to Southeast Asia within the EU. And in terms of the amount of exported plastic waste per capita, the Netherlands is even the world leader.
In 2021, this amounted to over 200 million kilograms; 70 million kilograms of which went to Indonesia, and 64 million kilograms to Vietnam. Unfortunately, the processing capabilities in many countries where plastic waste is shipped are inadequate for the massive amounts that end up there. As a result, this waste ends up in landfills and the natural environment, posing a threat to the health of humans and animals.
Fortunately, at the end of 2023, the European Union adopted a law that prohibits the shipment of waste to non-OECD countries (Organisation for Economic Co-operation and Development). This means that European countries must take more responsibility for their plastic waste and prevent it (and all associated problems) from simply being shipped to another part of the world.
Share of different end-of-life-options
The chart below shows the percentages of global plastic waste in 2019 that was recycled, landfilled, incinerated, or improperly processed.
In Europe, the recycling rate is higher than the global average, at 35%. In 2020, the Netherlands was even the leader with 45%. However, this percentage means that less than half of all plastic waste is recycled. Why not?
Why isn’t all plastic recycled?
Plastic is not "one material"; there are various types of plastic. These are all synthetic substances, made by humans. Plastics consist of polymers; long chains of the same (or very similar) molecules that form chains together. The exact appearance of these chains determines the properties of the final product. And these properties also determine whether and how the plastic can be recycled.
Plastics can be divided into three main categories:
Thermoplastics
This type of plastic consists of long polymer chains without branches, where the molecules are only loosely connected. As a result, these plastics melt when heated. The molecular connections can easily shift, allowing the plastic to be easily molded into different shapes.
Thermoplastics are highly recyclable. Examples of this type of plastic include PVC, polyethylene (PE), polystyrene (PS), and polyethylene terephthalate (PET).
Thermosets
The molecules in thermosets are much more strongly interconnected, which hampers movement between the chains. This results in a hard plastic that is difficult to deform. Upon heating, this type of plastic is more likely to burn than melt, and it is difficult to recycle. Polyester and epoxy are examples of thermosets.
Elastomers
This type of plastic is characterized by its ability to stretch or bend and then, when the force on the plastic is removed, return to its original shape and structure. Elastomers are, as the name suggests, elastic and therefore particularly suitable for applications such as shoe soles or car tires. Elastomers can be partially recycled, but often only ground into small particles. It is difficult to remelt elastomers without breaking the structure. Synthetic rubber is an example of an elastomer.
Recycled plastic is not yet profitable
Whether plastic can be recycled depends on the type of plastic. However, not all plastic that can potentially be recycled actually gets recycled. The main reason for this is the high cost of recycling. In Dutch waste management, incineration is the most financially attractive destination for plastic waste.
Why is it not economically viable to recycle all plastic waste from a financial perspective? Waste often consists of a complex mixture of various materials, which can also be heavily contaminated. The necessary steps for collection, sorting, cleaning, and the recycling process itself lead to high costs. Therefore, it is simply cheaper to work with new, "virgin" plastic.
Major recycler goes bankrupt
The fact that virgin plastic is much cheaper than recycled plastic has consequences for recyclers. In January 2024, the Dutch plastic recycler Umincorp went bankrupt. Due to inflation, higher wages, rising energy costs, and more expensive insurance, costs increased. Combined with the low market prices of virgin plastic from China and the US, 2023 was the worst financial year ever for the plant.
Umincorp is not the only recycler facing financial difficulties; according to the Association of Waste Companies, more recyclers are at risk of bankruptcy.
And if there are no more recyclers, well, then plastic waste just ends up back in the incinerator.
The plastic sector is not the only one where recyclers are under pressure. Recently, the Swedish company Renewcell also went bankrupt. They produce the material Circulose from recycled textile waste, but the company failed to secure their long-term financing.
Post-industrial recycling & post-consumer recycling
Plastic can be recycled at different points in its "lifecycle." We distinguish between plastic that is recycled during the production process and plastic that is recycled after it has completed its entire lifecycle, once the material has been used by consumers.
Post-industrial recycling (PIR)
This involves plastic that becomes a by-product or waste stream during the production process. Sometimes this plastic is reused in the same factory, and sometimes it is sold to other producers.
This includes, for example, plastic that solidifies on the outside of a mold and is trimmed off, or plastic that falls on the factory floor, or products with manufacturing defects that cannot be sold.
This is a clean and "pure" waste stream: the plastic can easily be reprocessed. Thus, this plastic is not really waste; it is new, cleanly produced plastic as a by-product.
Post-consumer recycling (PCR)
As the name suggests, this refers to plastic that is recycled after consumer use. This can be waste from households or from a commercial environment. Examples include plastic food packaging, plastic fibers in textiles, etc.
The downside of this stream is that the waste is used and therefore dirty. Think of food residues remaining in the packaging, or stains in textiles. The plastic must be thoroughly cleaned before new material can be made from it.
And people throw away all sorts of things in their trash, not just plastic. Therefore, to recycle the plastic from the waste stream, the waste must first be sorted. PCR therefore requires more intermediate steps and the percentage of usable material that can be extracted from the waste stream is lower than with PIR.
Methods of plastic recycling
There are various ways to recycle plastic.
Mechanical recycling
In mechanical recycling, the plastic is ground and melted into plastic pellets, called granulate or recyclate. Nothing changes at the molecular level of the plastic. Mechanical recycling proceeds through the following steps:
- Separation and sorting: The material is sorted based on properties such as shape, density, size, color, or chemical composition.
- Compression: Much of the plastic is not processed at the same location or immediately after sorting. To make transportation easier, the plastic is compressed into a smaller volume.
- Washing: Contaminants are removed, such as food residues or other traces of use.
- Grinding: The material is reduced to small pieces or flakes.
- Compounding and pelletizing: This step does not always occur, but in some cases, the flakes from the previous step are converted into granulate. This granulate is easier to use as raw material than the flakes.
Disadvantage of mechanical recycling
To be able to recycle mechanically, the waste stream must be well washed and sorted; to obtain high-quality granulate, you want one type of plastic as an "ingredient."
This is also an explanation for why recycling percentages are so low; products made from different types of plastic are not recyclable or only at very high operating costs. And many everyday products/packaging consist of more than one type of material. Consider, for example, the paper bread bag with a plastic window. According to research by Natuur & Milieu (2021), about 65% of the packaging in supermarkets cannot be recycled or only limitedly for this reason.
If waste is contaminated by more than 15%, for example, by labels made of a different type of plastic, it can no longer be recycled and goes directly to the incinerator.
High-quality recycling or downcycling
99% of all recycled plastic is recycled mechanically. Materials can be upcycled, high-quality recycled, or downcycled.
Upcycling
In upcycling, the recyclate is mixed with new, virgin plastic to form a new material. This new material is of high quality and is suitable for various applications.
High-quality recycling
High-quality recycling means that the plastic, after the recycling process, can be used again as a raw material for the same product. There is no change in properties or loss of quality. PET is an example of a material that can be high-quality recycled; PET bottles can be turned back into PET bottles.
Downcycling
However, in many cases, the recycled material does decline in quality. For example, because the plastic is too contaminated, mixed, or discolored. Or because the downcycled plastic loses certain properties, making it unsuitable for the original application. This type of plastic then finds a different use, for example, as insulation material in construction or as filling for duvets or pillows.
Chemical recycling
Chemical recycling is a very different process from mechanical recycling. This form of recycling is still under development and is currently only applied on a small scale. During chemical recycling, the plastic is broken down into the polymers and molecules it is made of. These molecules are the “end product” of the recycling, and new plastics can be built from them.
Pros and cons of chemical recycling
Chemical recycling makes it possible to separate additives such as scents and dyes from the plastic. And because chemical recycling breaks the plastic down to the base molecules, from which “new” plastic can be made, it produces very high-quality plastic.
This plastic can be used for food packaging, for example, while there are various regulations regarding mechanically recycled plastic for this application. For food safety reasons, only recyclate that has been collected separately by 95 percent and not sorted and separated from mixed waste may be used.
And through chemical recycling, you can also recycle products made from different types of plastics. Therefore, chemical recycling can recycle a large portion of all the plastic waste that is currently not recycled. Unfortunately, this does not always happen in practice, as chemical recycling is financially very costly. Chemical recycling is an energy-intensive process, and the chemical substances and catalysts needed come with a hefty price tag.
This form of recycling has a high environmental impact, and it is questionable whether the impact of recycling is still smaller than the impact of producing and processing new plastic. Chemical recycling is therefore a supplement to mechanical recycling, not a replacement.
Side-note; recycling is not the solution
Recycled plastic is more sustainable than virgin plastic because it does not require the production of new oil. This is advantageous since currently, 10% of all extracted oil is used for plastic production. With plastic production increasing annually, this percentage is expected only to rise.
However, recycled plastic is still plastic. If it ends up in the environment, it causes harm. Recycled plastic also breaks down into microplastics. Learn more about the microplastic problem in our article: Plastic & Sustainability; Everything You Want to Know.
There is also a disadvantage to recycled plastic compared to virgin plastic. The concentration of toxic substances is higher. These include toxic substances such as flame retardants, benzene, various carcinogenic substances, substances that affect human hormone balance, and substances that are very harmful to the environment (such as bromine and chlorine dioxins).
Graham Forbes of Greenpeace USA says, "The toxicity of plastic actually increases with recycling. There is no place for plastic in a circular economy, and it is clear that the only real solution to ending plastic pollution is a massive reduction in plastic production.
Simply put, plastic poisons the circular economy and our bodies, and pollutes the air, water, and food. We should not recycle plastic that contains toxic chemicals. Real solutions to the plastic crisis require global control of chemical substances in plastic and a significant reduction in plastic production."
Thus, recycled plastic also has several significant negative characteristics. This makes recycling not the solution to the plastic problem. And plastic, from a sustainability perspective, is a complex material. While it has a high environmental impact, in some cases, plastic can also be a more sustainable option than alternatives such as glass or cardboard. For example, read more about this in this LCA example: Food Containers: Glass or Plastic
The best solution for how we can handle plastic sustainably is to be conscious of our use of plastic. Read more in the paragraphs below.
So, what can we do?
Producers: make packaging that is easier to recycle
The choices a producer makes in the design and production of a product or packaging greatly influence recycling possibilities.
Packaging or products made from just one type of plastic are easy to recycle. If different types of plastic are used together, this is not the case.
And it’s not just about the exterior of the product, but also things like sealants (silicone sealant etc.) and fillers. The more different materials used, the harder the product is to recycle.
In food packaging, sometimes it’s a challenge to remove food residues. The easier this is, the better the packaging can be recycled.
And design also influences. In many sorting processes, packaging is separated via infrared detection. Bottles/tubes that tilt, for instance, because of a low center of gravity, are not correctly separated and therefore may not be recycled.
Consumers; pay attention to the composition of the product
If possible, choose a product made from just one type of plastic. As you’ve read earlier, such products are recyclable. And products made from multiple types of plastic are not.
And if you dispose of packaging made from different materials, throw away the different parts separately. For example, put the cardboard packaging in the paper recycling, and the plastic yogurt container in the plastic bin.
And if you deliver your packaging clean, you further increase the chance that it can be recycled. So don’t put other waste (like a cigarette butt) in a sealed package, empty your packaging thoroughly before throwing it away.
Producers & consumers: request recycled plastic
As you’ve read in this article, financially, virgin plastic still wins over recycled plastic, with all the consequences (such as recyclers going bankrupt) that entail.
What can we do about it? It’s a matter of supply and demand. If demand for recycled plastic increases, the price will rise. And it becomes more attractive for producers to offer more recycled plastic.
So choose recycled plastic if you have the option.
Consumers; keep this in mind when buying a product. Check if there’s an option that includes recycled plastic.
Producers: where possible, choose recycled plastic. As a raw material for your products, or as packaging material.