Plastics recycling

Definition

Plastics recycling encompasses all processes from the collection of plastic waste to its sorting and processing, through to the production of recycled materials (pressed recycled pellets) and their reuse in new products. Every year, some 830,000 tonnes of plastic waste are generated in Switzerland from short- and long-life applications. Almost half of this comes from packaging. The remainder is generated by the construction industry, vehicles, electrical and electronic equipment, agriculture and other sectors. Of the total volume, approximately 660,000 tonnes are incinerated with other waste. Only around 170,000 tonnes are collected separately. But more than half of the collected plastic is also used for thermal purposes in incineration plants or cement plants. Only 72,000 tonnes are actually recycled every year. In Switzerland, the focus is on PET recycling, which is an international leader with a material recycling rate of 82 percent. For other types of plastics such as polyethylene or polypropylene, however, there are no national recycling systems.  

Current applications and opportunities 

Specialised companies in Switzerland and abroad sort the plastics from the waste. These are then mechanically processed, melted down and pressed into recyclates and reused in new products. They are used in packaging, construction (pipes, seals), logistics (boxes, pallets) or textiles (polyester). 

The use of recycled materials conserves resources and reduces carbon emissions along the entire value chain. According to a study by ETH Zurich, 1 kilogram of plastic produces 4.9 kilograms of CO2 equivalents over its entire life cycle. Through recycling and the associated saving of new material, the value falls to 1.5 kilograms of CO2 equivalents. At the same time, using 1 kilogram of recycled plastic waste in production prevents the consumption of 3 litres of crude oil. The recycling of plastic waste can thus close the raw materials cycle in plastics production.  

Development in Switzerland is driven primarily by voluntary industry solutions. Efforts being made in the European environment are an effective driver. For example, the EU has made its Green Deal initiative subject to the principle of the circular economy. According to the Packaging and Packaging Waste Directive, which came into force in 2018, all packaging must be reusable or cost-efficiently recyclable by 2030. Market participants in Switzerland such as Coca-Cola and Nestlé also follow these guidelines. 

Challenges

With a recycling rate of 9 percent across all plastics, Switzerland is lagging behind its international peers. This is partly due to cost factors. On the other hand, Switzerland lacks comprehensive concepts and a suitable infrastructure for collecting and recycling mixed plastics. The big challenge is the variety of plastics used in consumer products. In electrical appliances, for example, plastics are often used along with other materials. Additives in coated packaging or adhesives are also a problem. In addition, incorrect sorting can also result in cross-contamination during collection, which affects the quality of the recycled material and the resulting product. The result is downcycling, where the product has less value on the market than the primary product.  

The basis for successful recycling, which results in higher-quality and higher-value products (upcycling), is separate and pure material flows. Switzerland has a lot of catching up to do in the area of sorting technology, in particular. With the exception of PET recycling, mixed plastics from separate collections have until now had to be transported to neighbouring countries where they are separated in state-of-the-art sorting plants. The collection infrastructure and raising awareness among the general public also play an important role. 

Replacing non-recyclable plastics with recyclable ones during the production of primary products optimises recyclability (design for recycling). In addition, a digital product passport is being developed in the EU, which will accompany the individual material throughout its entire life cycle. This allows a plastic to be clearly identified even in waste. It can also be used to identify any additives or harmful substances, some of which remain undetected at present and thus contaminate the recycled material. 

Focus on industry

In 2023, the total turnover of domestic companies in the recycling sector was between 100 million and 500 million Swiss francs. There is huge market potential in the internationally growing recycling market. The demand for high-quality recycled materials is much higher than their availability, which increases the need for innovative solutions. While plastic waste used to be primarily a cost factor, today it is increasingly regarded as a valuable raw material. 

This is also reflected in the increased demands placed on specialists. In 2020, for example, the profession of recycling specialist was created in the collection and sorting sector, which can be learnt during a three-year apprenticeship. Other areas of the value chain require expertise in plant construction, process engineering and other engineering disciplines. An awareness of raw material cycles across the entire value chain and good collaboration between recycling specialists and product developers are also crucial for devising innovative solutions.  

International perspective 

By international standards, Switzerland has led the way primarily with its pioneering work in PET beverage bottle collection. Countries such as Germany, Italy and Austria continue to make headway when it comes to innovative recycling technologies. For example, mixed household plastics are brought to Germany to be separated in state-of-the-art sorting facilities. Opportunities for Swiss players lie in technically demanding niches such as chemical processing or AI-supported infrared sorting of mixed plastics. Switzerland still has some catching up to do in terms of collaboration and knowledge exchange with international bodies and research partnerships, for example in projects such as the digital product passport. 

Future applications 

Digitised sorting processes improve accuracy during sorting. A highly sensitive infrared sensor identifies a type of plastic via its specific infrared spectrum. Equipped with AI, such a sorting plant can separate mixed plastics even more precisely based on empirical data, thus significantly increasing the recycling rate. 

New chemical processes will complement the existing mechanical processing of plastic waste. For example, the Valais-based start-up DePoly has developed a method that uses depolymerisation to break down different polymers into their basic building blocks. The advantage is that mixed waste of various origins can also be recycled. The resulting monomers can be used to produce new plastic products with the desired properties. This year, DePoly is opening its first demonstration plant in Monthey.  

The development of biodegradable bioplastics is also promising. They can be used in composites and adhesives or in textiles and footwear, where the materials previously used made recycling difficult or impossible. 

Plastics recycling therefore offers key technologies at several points in the value chain to conserve resources, reduce emissions and avoid dependency on fossil raw materials.