Jeff Spangenberger, materials recycling group leader from the U.S. Department of Energy’s Argonne National Laboratory, based in Illinois, U.S., discusses how the laboratory is investigating ways to recycle polypropylene plastics from shredder residue and how there are opportunities to be had when it comes to recycling electric cars at their end of life.
After a car has taken its final road trip, it usually heads to the auto recycler where the fluids are drained and valuable parts are removed for resale. The remainder of the vehicle is then sent to the auto shredder where the metals are recovered for recycling and the remainder of the material — auto shredder residue — goes to the landfill at a cost. The entire system is economically sustainable because everyone in the system makes money.
As cars become lighter and lighter to achieve better fuel economy, however, the metal components are getting switched out for plastics that are not recycled, making it harder to achieve the financial rewards for recycling cars at end-of-life. Perhaps even more importantly, the introduction of electric vehicles to the auto recyclers feedstock add additional challenges to make the economics work because the batteries can have a significant negative value. Today, the percentage by weight of a vehicle going to landfill is increasing.
As cars have changed over the course of 20 years, so too have the quantity and quality of plastics that go into them. The plastics used in cars are made to last for their entire lifetimes – 10 to 15 years or more. As a result, these plastics are much better and more durable than single-use plastics, and they can be worth more when they are recycled.
Researchers at the U.S. Department of Energy’s Argonne National Laboratory are investigating ways to recycle plastics recovered from residues from auto shredders.
These plastics, particularly polypropylene, can be recycled into brand new automotive parts. Although fabricating new plastics from scratch remains fairly inexpensive, there are advantages to recycling these plastics, and Argonne has the technology to do just this.
Argonne’s technology sorts and converts shredder residue plastics into compatible fractions, which would then go to a processor to produce pellets. These pellets are what are sold to vehicle parts manufacturers and suppliers for different vehicle components.
The opportunity to recycle vehicle plastics is clear, and the need will only increase as cars continue to include a greater proportion of plastic components. The technology exists for recovering these plastics and converting them into useful vehicle components, but researchers are still trying to build a market for them.
One additional new opportunity for vehicle recycling that will emerge this decade involves the recycling of electric vehicles – specifically, their batteries. Electric vehicle batteries contain a great deal of valuable metal components and weigh more than a thousand pounds, but the scale, infrastructure, and technologies do not yet currently exist for recycling them in a cost-effective way. Scientists, including those working at the ReCell Center, are looking for ways to better recover and recycle valuable material from electric vehicle batteries turning their negative value into a value-add vehicle part at end of life.
The opportunities and challenges of vehicle recycling are numerous. Metals will continue to make up the lion’s share of valuable components that can be recycled. However, the move towards light-weighting materials and electric vehicles is leading to increased interest in recycling automotive plastics and lithium-ion batteries.
As landfill costs rise, and metal content in vehicles diminish, expanding the list of recycled materials from end-of-life cars will prove an appealing solution, both for financial and environmental sustainability.
To find out more about Argonne National Laboratory, visit www.anl.gov