Systematic approach to recyclate sorting yields dividends

Düsseldorf - An optical sorting station from the Bühler Group (10/E54) brings together the key elements of successful optical sorting, including plant engineering, sorting technology, pneumatic conveyors, pre-conditioners and auxiliary equipment - reportedly a first for the plastics industry.

"For the past 13 years we have been supplying stand-alone Sortex optical sorting modules to the plastics processing sector but now, we are focusing on supplying complete systems including all the necessary equipment such as air locks, cyclones, filters and screw conveyors to convey the product between stages and, if required, to re-introduce it into the system for resorting," says Alexander Prömer, European Territory Manager at Bühler. "Reprocessors do  not want to buy from 10 vendors when they are putting together a separation system. We offer a single source supply and everything is manufactured in house so we can take complete responsibility for the system."

The first such integrated system was supplied to recycling company ITW Poly Recycling around two years ago. The facility, in Weinfelden, Switzerland specialises in PET processing, supplying food grade and non-food grade recycled PET products to clients in Switzerland and across Europe. Two other installations are in operation, including one at reprocessor Deceuninck.

For flake processing, the optical sorting station features purifying, refining, sizing and grading stages that can include one or more Sortex optical sorters. Flakes can be fed into one end of the station and collected at the other end - ready for bagging or further processing.

Bühler's custom-designed Sortex, high-resolution cameras allow double-sided product viewing from up to four cameras per module. Ultra-flexible broadband LED lighting, broad spectrum lighting, enhanced InGaAs and PROfile (shape) technologies are able to remove unwanted colored flakes, misshapen pellets and foreign materials and reduce unwanted  polymeric materials.