The Kent County Department of Public Works (DPW) has installed new technology at its Recycling & Education Center that will further improve plastic recycling.

With $150,000 in grant funding from the Michigan Department of Environment, Great Lakes and Energy (EGLE), the DPW purchased a new optical sorter to replace the previous one, which reached its useful life.

The optical sorter reads different types of plastic as they move down a conveyor belt and automatically sorts different plastics based on their grade. The optical sorter is set to pull out #5 plastics, or Polypropylene, which are used for common items like yogurt containers, potato chip bags, cereal bags and more. It also sorts #1 plastics, or Polyethylene Terephthalate, which are typically clear plastics for water bottles or other food containers.

“With a new and upgraded optical sorter, the DPW can more quickly and efficiently identify these valuable materials and ensure they are sorted properly,” said Nic VanderVinne, resource recovery recycling manager at the DPW. “Many people tend to throw away some of these materials – fast food cups, yogurt cups and more – when they can actually be recycled and put to new and better use. The DPW is thankful to EGLE for the grant funding which will allow the optical sorter to streamline our process.”

The optical sorter uses light to determine various plastic grades and then fires air jets to propel those plastics into the appropriate bins. The sorter makes the process of spotting and separating these plastics more efficient and automatic than sorting them by hand as the plastics can come in different colors.

Though the DPW has always recycled these plastics, VanderVinne said it’s a common misconception that plastics are not recyclable. The DPW currently takes plastics #1-7, and they can be identified by looking at the triangle symbol usually located on the bottom of many plastic items. The DPW will continue to recycle all these grades of plastic, and the optical sorter allows for the higher value and more desirable plastics to be separated out. The #5 plastics can be sold directly to major plastic resin producers. Any increased revenue helps to offset the costs of processing single stream recycling, making the overall system more affordable for residents and businesses.

“The optical sorter makes sorting these materials efficient and provides a revenue stream for the DPW, benefiting the environment and Kent County residents,” VanderVinne said. “It’s a win-win for us and for the community to have this resource.”