Recent testing by a supplier of sensor-based sorting systems for recycling plants has shown that polystyrene (PS) is not only made for recycling, but also made for sorting, according to an announcement from Ineos Styrolution (Frankfurt, Germany).
The testing was performed under the umbrella of Styrenics Circular Solutions (SCS) using near-infrared (NIR) sensor technology developed by Tomra (Asker, Norway). Post-consumer plastic waste was sorted in a multi-step process including initial sorting from post-consumer waste, grinding into smaller flakes, washing, drying, and flake sorting. The resulting purity of polystyrene turned out to be higher than 99.9%
One reason for the good result, according to Jürgen Priesters, Senior Vice President, Circular Economy at Tomra, is the specific properties of the material. “Styrenic compounds have a unique signal that make it easy to identify specific properties of the material that results in very precise sorting, an advantage that some of the other polymers do not have.”
Tomra’s findings prove that today’s sorting technologies achieve a purity level beyond what is required to successfully recycle polystyrene through both mechanical as well as advanced recycling processes. Along with Ineos Styrolution’s investments in multiple recycling projects, this takes the company another step closer to developing closed-loop solutions for styrenics, said Ineos’ announcement.
Ineos noted that the company continues along its path to build the best recycled ABS in the world and chemically recycled polystyrene at commercial scale. The company is investing in multiple projects in Europe and in the Americas to set up recycling facilities based on the depolymerization process.
Sven Riechers, Vice President, Business Management, Standard Products EMEA at Ineos Styrolution, commented: “These findings on polystyrene sorting make styrenics a material of choice for a circular economy and confirms our statement that styrenics are made for recycling like no other.”
Image courtesy Ineos Styrolution