Mazda has developed a technology to recycle bumpers from end-of-life vehicles into bumpers for new cars, saying it’s the first automaker to “close the loop” on bumper recycling.
Bumpers make up a large proportion of the plastic used in vehicles, and when a car reaches the end of its useful life, bumpers are typically shredded and incinerated to recover heat energy, the company says. Because many end-of-life vehicles are over 10 years old, the composition of the bumper’s polypropylene plastic and the adhesive properties of the paint vary considerably, creating a challenge to recycling the bumpers into new products.
To overcome these barriers to recycling, Mazda began designing its bumpers to be easily recyclable in the 1990s and developed technologies to remove paint from old bumpers. In 2001, Mazda used the plastic harvested from old bumpers to reinforce new bumpers, but as its paint-removal technology improved, the company began recycling the plastic resin into new bumpers for select vehicles and replacement painted bumpers.
Last month, the automaker debuted its new automated bumper-recycling technology, which can more efficiently and cost-effectively convert used bumpers into raw plastic resin to manufacture new bumpers.
After the bumpers are crushed into pellets, a machine, similar to those used to remove contaminants from cereal grains, shakes the pellets and blasts them with air, eliminating any unwanted materials like metal pieces. Previously, contaminants had to be removed by hand – a labor-intensive process – so this equipment greatly improves the efficiency of bumper recycling.
Mazda’s earlier bumper recycling technologies could not process used bumpers from different manufacturers at the same time. But the new system can remove paint from the bumper of any manufacturer, regardless of the variable adhesive properties of the paint and plastic composition. A kneading machine, similar to equipment used for processing foodstuffs and chemicals like rubber and plastics, applies a powerful force to the bumper pellets, stripping off paint without having to heat the plastic.
Mazda is initially collecting bumpers from end-of-life Mazda vehicles in the Hiroshima, Japan, area and recycling the plastic to make up at least 10 percent of the rear bumpers for its Biante minivan, a vehicle available in Japan.