Will recycling save the world from plastic waste?
The magnitude of rapidly accumulating plastic waste in our natural environment has revealed itself through new alarming numbers; 8 million metric tons of plastic ends up in our oceans every year. Recycling is often given as a panacea for the plastic crisis. So, could it save the day?
How to fight the global plastic crisis
The idea of recycling has been around for a while. The recycling symbol was introduced over 40 years ago, but according to Ellen MacArthur Foundation, today only 14% of plastic packaging is collected, and only 2% is recycled into the same quality material. Out of the 8,3 billion metric tons of virgin plastic ever produced, the vast majority — 79 percent — has ended up in landfills or our natural environment. So, while recycling is being provided as the weapon against the ever-growing plastic waste monster, we are far from winning the battle.
This does not mean we need to throw in the towel. During the past couple of years, governments and companies have taken up some bold measures to tackle the plastic waste issue. The Ocean Cleanup started cleaning up the Great Pacific Garbage Patch last year with the ambitious goal of collecting 90% of floating ocean plastic. While this is crucial, it should be noted that with the current technology it is almost impossible to clean oceans from microplastic waste. Therefore, to solve the plastic waste crisis, all the means out there are needed: We must commit to the 4Rs, i.e. reducing plastic consumption, reusing plastic items as many times as possible, recycling more rigorously, and finally, replacing plastic by more sustainable materials.
Why enhancing recycling is pivotal
It is estimated that when plastic ends up in the natural environment, it takes more than 400 years to degrade. If plastic ends up on a landfill, the waste mountain keeps on growing. When incinerated non-renewable carbon is released into the atmosphere. Hence, effective collection and recycling of plastic waste is more than crucial.
While a whopping 91% of plastic is not recycled globally, there are significant differences between areas. In Europe, about a third of plastic waste is collected for recycling, a third for waste-to-energy processes and the rest ends up in landfills or nature. The corresponding numbers globally are 9% collected for recycling, 12% waste-to-energy, and 79% in landfills or natural environment.
How to improve plastic recycling
To get the plastic recycling rates up, we need to do four things. Firstly, we must develop the recycling infrastructure globally, especially in developing countries where recycling systems are altogether missing, and where the impact of the plastic waste problem is the most prominent. Secondly, we need to improve our plastic recycling technologies to get more high-quality material to circulate. Thirdly, we need to educate people on the importance of recycling and provide clear instructions on how to do it. And finally, we need better collaboration throughout the value chain – from product design to waste management sector.
An encouraging example of a successful waste collection system is found in Finland, where over 90% of PET plastic bottles are collected for recycling. The collection is based on deposit-return system, where consumers are encouraged to return empty beverage packages for recycling against a small refund per bottle. Besides the small monetary incentive, what motivates Finns to recycle is the ease of it: public recycling bins and collection points are accessible across the country.
After collection, the bottles are crushed, melted and granulated to be used in new plastics products. Part of this recycled PET is used in manufacturing new bottles. New bottles, however, like most other plastic items, are not 100 % made of recycled material but require a mix of recycled material with virgin plastic.
Only part of the collected plastic waste is recycled, why?
Part of the plastic packaging scrap collected, typically 40-60 %, is too heterogenous, contaminated or otherwise too low in quality for recycling, and therefore ends up being incinerated.
Currently plastics recycling is almost entirely carried out by the mechanical route. Mechanical recycling is a process where plastics are recycled into new raw materials without changing the basic structure of the material. And therein lies the challenge: mechanical recycling requires separating different plastic types. To make recycling easier, Adidas has developed a shoe made entirely from one plastic type. Many items contain so many different types of plastics or other materials that mechanical recycling becomes impossible.
Luckily new technologies for plastics recycling are under development. Chemical recycling, also known as feedstock recycling, means breaking down the long polymer molecules in plastics into smaller molecules. It encompasses a variety of technologies including pyrolysis, in which heat and pressure are applied to plastic waste in the absence of oxygen. The main output of pyrolysis is an oily liquid which can be used as raw material for fuels and chemicals in the petrochemical industry. The development of chemical recycling technologies is motivated by two main needs, which are 1) the need to safely and efficiently process materials difficult to treat with mechanical recycling and 2) the need to produce recycled materials of high quality. Chemical recycling paths are not substitutes to mechanical recycling of plastics, rather the different technologies complement each other.
Recycling of Sulapac
Sulapac waste can be refined by several technologies. For example the mechanical recycling of Sulapac Premium has been demonstrated by VTT, Technical Research Centre of Finland indicating that mechanical properties of the material last up to five cycles. The infrastructure for some of the possible recycling routes is not mature yet, but organic recycling via industrial composting offers a sustainable recycling route for Sulapac already today. Chemical recycling via pyrolysis and pulpering with cardboard waste are also interesting options which we are currently investigating. As the recycling systems are still under development, Sulapac has been designed so that it is a better option than conventional plastic, regardless where it ends up. For example, when items made of Sulapac Premium or Universal are incinerated, no fossil CO2 is emitted, as the materials are made entirely from bio-based raw materials. Also, the CO2 and CO emissions are smaller compared to for example polypropylene.
Collaboration is key in solving the plastic crisis
The solutions of the future will be based on combining different recycling technologies and knowhow. Scientists, companies and policymakers should work together towards a common goal and best practices should be shared across regions. Along with the development of plastic recycling, and change of consumption habits, new sustainable materials are needed. To seize their full circular potential, these new innovations must also be taken into account in the development of the recycling systems.
Saving the world from plastic waste isn’t an easy task, but the humankind is qualified for the job. Will you join us on the mission?
Maija Pohjakallio, D.Sc. (Tech)