Market A circular
Market A circular bioeconomy of plastics By: Anna Tenhunen, Senior Scientist Holger Pöhler, Professor of Practice VTT Technical Research Center of Finland Espoo, Finland How can we tackle plastic pollution, greenhouse gas emissions and maintain the societal benefits that plastics offer for developed and emerging societies at the same time? A general ban of plastics is obviously not a realistic solution. The short answer is through a circular economy of plastics. VTT’s vision is to stop plastics pollution and to make the plastics value chain climate neutral by establishing material circularity, while maintaining material performance and economic feasibility of plastics. Figure 1 depicts this vision and roadmap to transform the current status. The tools to transform the linear economy and decouple economic growth from resource consumption are eco- design and circular business models such as reuse. The technological solutions to stop plastic pollution are intelligent plastic waste collection and separation systems, repair and refurbishment, and different recycling technologies to accommodate the material and product requirements of plastics. Renewable energy sources and renewable carbonbased feedstock (recyclates, biobased and CO 2 -based) as well as alternatives to plastics will significantly reduce the impact on climate change. To realize VTT’s vision for a circular economy, Fig. 2 shows several options to create circularity. The current status of the plastics economy is displayed in blue colour. The green cycles show how circularity can be achieved by different cycles: • Reuse cycle: product or article level • Polymer cycle: macromolecular level • Monomer cycle: building-block level • Biological cycle: biodegradation to soil • Biological carbon cycle: biodegradation to carbon dioxide and methane • Technical carbon cycle: capture of CO 2 • Energy cycle: recovery of the energy Making the Plastics Economy Carbon Neutral Plastics have rather carbon-intensive life cycles which accelerate climate change, especially due to the fact that the vast majority of plastics are made from virgin fossil raw materials. The manufacturing of plastics requires energy intensive processing and also contributes to direct greenhouse gas emissions [1]. The production of fossilbased commodity plastics causes an average of 2.5 tonnes of CO 2 emissions for every tonne of plastic produced. Furthermore, incinerating, landfilling, recycling and composting processes also release CO 2 [1]. The carbon present in 1 tonne of plastic materials corresponds to approximately 2.7 tonnes of carbon dioxide, which is released when the material is incinerated or completely degraded. The industries need secure, affordable and functional feedstock for their production, which makes it challenging to decouple from virgin fossil resources. Yet the sustainability megatrend and the environmental problems linked to plastics and the plastics industry are driving change in future feedstocks. The future circular plastics economy will rely on sustainable raw materials: biobased feedstock, carbon capture and utilization technology (CCU) based polymers and recycled plastics. The recycled plastics will mainly initially originate from the fossil-based sources, but also eventually from recycled biobased and CCU-based polymers. In a circular economy, the recycling of existing plastic materials is an important source for renewable carbon. However, it is clear that only recycling the fossil-based polymers will not be able to provide the lion’s share of renewable carbon in a sustainable manner in the near future [2]. It is evident that the growth of plastics production cannot be met sustainably if the raw material base is not widened. McKinsey has estimated that 50 % of plastics worldwide could be reused or recycled by 2030. This means that by 2030, up to almost one third of plastics demand could be covered by production based on previously used plastics rather than from virgin fossil feedstock. This estimate is based on a high-adoption scenario, comprising a massive increase in mechanical recycling volumes, a take-off in pyrolysis, and oil prices at around USD 75 per barrel. If by 2030 the total production of plastics is doubled from today’s value, taking into account McKinsey’s estimate of increased recycling, the use of virgin fossil raw materials would still grow by one third. This simple calculation shows that even if the increased recycling of plastics does take place, there will still be an enormous need to use alternative raw materials, such as cellulose, starch, sugars, fats and oils, and CO 2 from the atmosphere. 52 bioplastics MAGAZINE [03/20] Vol. 15
Market Current status VTT’s vision Plastics are beneficial, versatile and affordable materials mostly used in a make-use-dispose economy Ecodesign Circular business models Establish material circularity while maintaining performance and economic feasibility of plastics Plastic waste ending up in the environment harms natural and economical ecosystems Collection & separation Reuse Recycling Stopping plastics pollution The plastics value chain is based on virgin fossil feedstock and contributes strongly to climate change Bio-based feedstock Recycled feedstock Carbon capture and utilization Renewable energy sources Stopping the plastics value chain contributing to climate change Figure 1. VTT’s vision and roadmap for creating a circular economy for plastics Biological CO 2 Cycle Technical CO 2 Cycle Energy Cycle Fossil Feedstock Monomer Cycle Photosynthesis Biobased Feedstock Recycled feedstock Society Polymer Cycle Reuse Cycle Incineration IMAGE SOURCE: VTT Plastics Value Chain Biodegradation Cycle Landfill Figure 2. Overview of VTT’s vision for circularity of plastics bioplastics MAGAZINE [03/20] Vol. 15 53
