David Shonnard, Research Professor and Professor Emeritus, Department of Chemical Engineering, Michigan Technological University
"Sustainability Assessments of US Plastics Supply Chains using Systems Analysis"
Abstract:
A linear plastics supply chain, which closely represents the current US condition, features fossil resource extraction for plastics production and disposal or incineration for end-of-life plastics. A circular plastics supply chain relies in closed-loop recycling processes with little disposal. A transition from a linear to a closed-loop circular economy for plastics is viewed as essential in solving the problems with plastics supply chains and waste. However, the sustainability of such a transition is not well understood from the perspective of greenhouse gas emissions and energy consumption. In this research, a system analysis framework was applied and an optimization model was developed and implemented to determine the best end-of-life (EOL) management processes and locations of emerging recycling infrastructure in the U.S. This was accomplished by minimizing the environmental impacts of closed-loop material flows with PET and polyolefin plastics packaging as a case study.
The systems analysis framework in this research combines material flow analysis (MFA) with environmental life cycle assessment (LCA) data for all processes in the supply chain. Our systems analysis model includes U.S. material flows from virgin resin production through several semi-manufacturing processes and finally to EOL treatments and recycling. These recycling processes include emerging advanced recycling technologies for which data is available such as pyrolysis of polyolefin wastes and hydrolysis/solvolysis of waste PET packaging. The basis for the system optimization is the annual US plastics packaging material flows that enter EOL management based on national US EPA waste generation statistics and county population density data. From a set of existing and proposed future facility locations for material recovery facilities (MRFs) and plastics recycling facilities (PRFs; mechanical and chemical recycling), optimum transportation distances, facility locations and capacities were determined. In the best scenario, reductions in greenhouse gas emissions greater than 50% were predicted compared to a linear economy for PET and polyolefin packaging. Systems analysis provides valuable insights into the environmental and energy impacts of emerging sustainable materials and energy technologies at a large scale in the US and potentially other regions of the world.
Bio:
David R. Shonnard is Research Professor and Professor Emeritus in the Department of Chemical Engineering at Michigan Technological University. He obtained a PhD in 1991 in the Department of Chemical Engineering at UC Davis and conducted postdoctoral research at Lawrence Livermore National Laboratory from 1991-1993. He has over 35 years of academic experience in sustainability issues in the chemical industry and green engineering. Research interests are in efficient upcycling of waste polymer materials, wood-based advanced biofuel process development, and environmental life cycle assessments (LCA) and techno-economic analyses (TEA) of renewable energy and battery storage systems, and of advanced biofuels and bioproducts. He is co-author of the textbooks “Green Engineering: Environmentally-Conscious Design of Chemical Processes”, published by Prentice Hall in 2002, and “Sustainable Engineering: Concepts, Design, and Case Studies”, published by Prentice Hall in 2012. He has co-authored over 300 peer-reviewed publications, edited books, conference proceedings papers, and technical reports. He has received numerous honors and awards for teaching and research. These include the Ray Fahien Award, from the American Society for Engineering Education in 2003, The Research Award in 2019 from the AIChE Sustainable Engineering Forum, and the Michigan Tech Research Award in 2020, a university-wide award.