Plastic is everywhere. Our society cannot do without it. Plastic has numerous advantages. It’s an extremely versatile and inexpensive material. Today, plastics are mainly made from petroleum. Unfortunately, when plastic products reach the end of their useful life, they often end up in an incinerator, and burning plastic releases very harmful toxic chemicals into the environment. One way to avoid this would be to stringently apply sustainable production methods to plastic, incorporating the material into a circular economy in which as much plastic as possible is recycled. This would mean that the main raw material for plastic would no longer be petroleum but rather would be shredded plastic waste. But can the plastics industry really be made 100 per cent sustainable? Researchers from the renowned Swiss Federal Institute of Technology (ETH) in Zurich have demonstrated the feasibility of this game-changer in a recent study.
The research team analysed the complete value chains of the 14 most common types of plastic, such as polyethylene, polypropylene and polyvinyl chloride. They make up 90 per cent of the plastic products manufactured worldwide. In their study, the ETH researchers showed that a closed cycle for plastics is feasible without exceeding the earth’s capacity to function in a healthy manner, that is, its “planetary boundaries”1. To achieve safe levels for plastic production, the study determined that at least 74 per cent of the plastic we use needs to be recycled. The study also notes that recycling processes need to be improved.
According to the ETH scientists, the carbon needed for producing the remaining 26 per cent of the plastics we use could be obtained using two technologies: carbon capture and utilisation2 (CCU), which separates CO2 from combustion processes or from the atmosphere, and bioenergy with carbon capture and storage3 (BECCS), which extracts energy from biomass and is sometimes called a “negative emissions technology”. “Recycling alone is not enough, we need all three pillars,” says lead author André Bardow, Professor of Energy and Process Systems Engineering at ETH Zurich. “A global recycling rate of 74 per cent is a very ambitious goal,” admits Bardow. However, he considers it realistic to achieve by 2050.
The researchers point out that plastic products will have to be better adapted to the circular economy in the future. To this end, manufacturers should work more closely with recyclers. According to the study, it would be desirable if plastics manufacturers had a broader understanding of the responsibility they bear. Today, responsibility usually ends when the product leaves the factory gates. The scientists are calling for product responsibility to be extended to cover the entire life cycle of a product. This includes disposal and recycling, which serve as the basis for establishing a sustainable plastics cycle. One thing is clear: recycling is the way to go. It does not have any serious disadvantages, which is why it should be a top priority in the transformation of the economy towards sustainability, and there are conflicting goals, as there can be in many other areas. For example, the production of synthetic fuels, which is very energy-intensive. Or the use of biomass, which competes with the production of important foodstuffs. The recycling of plastic, on the other hand, does not lead to such conflicting objectives. “Recycling should be intensified wherever possible,” says Bardow. “A good rule of thumb is: more recycling of plastic always leads to more sustainability.”
Source: ETH Zurich
