Probe Identifies Plastics, Aids In Recycling

Technology developed by researchers at Purdue University, West Lafayette, Ind., is helping to make the recycling of plastics a practical alternative to landfills. Using the principle of Raman spectroscopy, the approach uses a laser to cause a sample's molecules to vibrate. That scatters light in a pattern that is specific for each type of plastic, explains Purdue professor Edward Grant (also CEO of SpectraCode Inc., a company that is commercializing the technology). The entire identification cycle requires less than one second and when integrated with a conveyor automation, such a system is capable of identifying the chemical composition of more than 100 pieces per second, or 500 tons per day, Grant says. That means it could be used to screen commercial and post-consumer waste in factories, warehouses, recycling centers, and scrap yards, he adds. The probe, which also can be provided as a hand-held device, has no moving parts and does not require precleaning or precise positioning of the plastic material. Visteon, Ford Motor Co.'s automotive component operations, is using the technology in its recycling efforts. "Previous technologies for identifying dismantled materials were too slow and relied too much on operator accuracy," says Bill Orr, manager of Ford Worldwide vehicle recycle planning.