Once the input material is assigned to one of the three classes, it goes through dedusting. A counterflow classifier system reliably separates dust and fine particles from the ground material, with an efficiency of up to 99 percent. This is one of the platform's distinguishing features, Bartosch Jauernik, group director product management at Sesotec told Sustainable Plastics. It also helps protect against damage to downstream equipment.
The dedusting system is connected to the Varisort Compact sorter through standard vacuum conveying units, which ensure smooth material transport. The conveyor technology and sorting are centrally connected via a control unit. The integrated automatic start and stop function ensures the highest possible operating convenience, according to Jauernik.
At the core of the new sorting platform lies the Varisort Compact sorter, which divides mixed material flows, for example PET bottles, electrical waste, scrap metal and household waste into uniform fractions. It has three different sensors: color, metal, and a near-infrared sensor which detects different types of polymers.
The Pre-Sort offers maximum process flexibility through any combination of sensors and a choice of different sorting sequences. Thanks to two tracks for automated double sorting, the sorting platform also ensures high material quality, with purities between 85 percent and 95 percent.
"After dedusting, the material goes through the first line, which divides it into good and bad material," Jauernik said. An electronic analysis then activates the air ejection unit with exact timing and positioning, which removes the contaminants from the material flow. State-of-the-art signal evaluation technologies guarantee high detection accuracy and an evaluation of up to 500,000 parts per second.
"After the first sorting, the good material goes through line two, for resorting," Jauernik added. The Pre-Sort system has a throughput of 600 kg per hour and processes grain sizes from 2 mm to 10 mm.
The system components sit on a mobile platform, meaning it can be moved around and placed wherever it's needed. "The key word for the new sorting platform is flexibility," Jauernik explained, adding that some clients wanted the flexibility to move operations elsewhere after working on a location for a few months. At almost 6 tons, a forklift is necessary for transporting the platform around. It measures 5,700 mm x 2,350 mm x 3,258 mm and is designed for rapid commissioning of the plant. All the necessary parts, such as material conveying, dedusting, and sorting, are factory-installed and thus ready for use in the shortest possible time.
"Fakuma not only provides us with unparalleled opportunities for presenting our innovative technologies, but also for intensifying dialogue with customers and partners," said Dietmar Dieing, Sesotec vice president of sales. "It's a crucial forum which underscores the relevance of progress and sustainability in our industry. For Sesotec, Fakuma is much more than a trade fair — it's a stage for the future of the entire plastics industry."
Asked about the state of the plastics recycling industry, at a time when recycled resin prices are under severe downward pressure because of persistent weak demand, competition from the falling cost of off-spec virgin plastics, and cheaper imports from Asia, Dieing said Sesotec is yet to feel the heat. The company's sales have remained stable throughout 2023, he said, while noting that comprehensive conclusions cannot be drawn until the end of the year.