Japanese motor company Mazda has developed a process that it claims can enable any used-car bumpers to be recycled into raw plastic resin for reuse in new vehicles.
Depending on the vehicle manufacturer and age of the vehicle, used bumpers vary considerably in terms of the composition of polypropylene plastic and the paint's adhesive properties.
The process itself makes use of a kneading machine similar to the type used for processing foodstuffs or chemicals. In use, it applies a powerful shear force to the crushed bumper pellets, effectively stripping off the paint, regardless of the plastic composition or paint properties and without having to heat the plastic.
As the process can recycle all types and makes of bumper, it eliminates the need to use separate systems for automakers' products.
Additionally, the process automatically removes any metal attachments from the bumpers, significantly increasing recycling efficiency.
Until now, unwanted materials, such as metal attachments, had to be removed by hand. Now, once the used bumpers are crushed into pellets, a machine similar to those used to separate contaminants from cereal grains removes unwanted metal pieces by shaking the pellets and directing airflow over them.
Source: theengineer.co.ukAdded: 4 February 2009