Economic and Environmental Comparison of Emerging Plastic Waste Management Technologies

Investigator: North Carolina State University

Start Date:
October 2021

Award Amount:

The global annual demand for plastics is 400 million metric tons, and this is projected to triple by 2050. However, only 8.7% of plastics are recovered in the US and the supply of reprocessed plastics only meets 6% of the demand for plastic products. Therefore, improving plastics recycling is critical to building a more circular economy. Currently, cost-effective recovery of plastics is limited by separation efficiency, contamination, and quality degradation during collection, separation, and conventional mechanical reprocessing. Chemical recycling is an emerging and potentially scalable alternative to convert waste plastics into virgin-quality resins1 or refinery feedstocks. Commonly discussed chemical reprocessing strategies include polymer recycling (dissolution/precipitation), monomer recycling (solvolysis and pyrolysis), and plastics-to fuels. Chemical processes are also complementary to advance the selectiveness of polymers in mechanical recycling by extracting additives and separating different types of polymers. However, more data are needed on the economic and environmental implications of chemical recycling relative to conventional mechanical recycling before large-scale implementation begins. Therefore, the goal of the proposed project is to comprehensively assess the economic and environmental performance of new technologies for chemical recycling of plastics using life-cycle assessment (LCA). The project will provide practical recommendations for the solid waste industry to cost-effectively improve the plastics recycling rate and associated material quality while reducing environmental burdens.

Our goal motivated the following research objectives:

• Compare the costs and environmental impacts of emerging advanced chemical recycling technologies to existing management scenarios (e.g., mechanical recycling, landfill, and incineration), while considering the quality, contamination, and separation of plastic materials 2

• Estimate the environmental and economic implications related to changes in efficiency and productivity of emerging plastic waste management strategies as the technology matures and is implemented at full scale.

• Develop strategies (mixes of technologies and policies) that cost-effectively improve the environmental profile of plastic waste management alternatives.