Credit: Pixabay/CC0 Public Domain
Barcode readers excel at quickly identifying groceries and other products. Could a similar idea work at industrial recycling facilities to make sorting different plastics quicker and more cost-effective? The answer, according to a research team at the University of Buffalo is yes.
Unlike traditional barcode scanners, which rely on optical sensors, the team is developing a system that creates "three-dimensional transient thermal barcodes" that could rapidly identify plastics moving on conveyor belts.
The work is described in a Communications Engineering study.
"Our goal was to develop a cost-effective, scalable and industrially relevant plastics sorting technique that addresses the key prevailing scientific gaps restricting the recycling of plastics," says corresponding author Amit Goyal, Ph.D., SUNY Distinguished Professor and SUNY Empire Innovation Professor in the UB Department of Chemical and Biological Engineering.
"Our goal was to develop a cost-effective, scalable and industrially relevant plastics sorting technique that addresses the key prevailing scientific gaps restricting the recycling of plastics," says corresponding author Amit Goyal, Ph.D., SUNY Distinguished Professor and SUNY Empire Innovation Professor in the UB Department of Chemical and Biological Engineering.
Goyal directs the UB Initiative on Plastics Recycling and Innovation, which is designated as a New York state Center for Plastics Recycling Research and Innovation by the New York State Department of Environmental Conservation (DEC).
The system, he says, aims to "improve the quality of sorted plastics by reducing contamination and, hence, increasing the recycling of these materials to help enable a circular economy." He adds that it "is estimated that one ton of recycled plastic saves 5.7 megawatts of electricity, 685 gallons (2,593 liters) of oil, and 30 cubic yards (23 cubic meters) of landfill space."
Plastic recycling rates remain low
Plastic waste generated by households and businesses is sent to material recovery facilities, where plastic is separated from other waste. This is often done by hand, which can result in false identification and poor-quality sorted bales.
Plastics are then separated into different types. Presently, there is a lack of cost-competitive and accurate techniques that can effectively identify plastic types by their resin codes.
Developing techniques—including near-infrared spectroscopy, Raman spectroscopy and laser-induced breakdown spectroscopy—suffer from one or more issues. These include poor sensitivity, subpar selectivity, slow speeds, inability to detect black plastics, or an inability to operate in standoff mode (identifying plastics from a distance) that is often required in material recovery facilities.
These limitations explain, in part, why plastic recycling rates remain relatively low worldwide.
No comments:
Post a Comment