Stadler develops delabeler to address plastic sorting issue

Stadler, Altshausen, Germany, invests 5 percent of its revenue every year in research and development to search for ways to maximize the efficiency of the recycling process and the quality of the output. When the company saw an opportunity to improve the process for plastic bottles, it developed a specific solution to remove the labels, according to a company news release.

Rok Mežič, head of research and development Slovenia, who led the development process of the machine, explains, “Bottles make up a large proportion of plastic waste, and they present a particular issue to the recycling industry: the labels are made of a different polymer and color than the bottles, which negatively affects the accuracy of the sorting process. At Stadler, we saw the need to address this issue, and developed a delabeler to remove the labels automatically at the beginning of the process in order to achieve high-quality sorting and good purity rates.”

The Stadler delabeler removes labels from bottles of all types, achieving a quality standard of up to 80 percent of labels removed. It processes a mass flow of up to nine tons per hour depending on the particle size and material composition.

The Stadler delabeler’s robust overall construction and high resistance to impurities and troubling materials result in durability and high performance throughout its life cycle, the company says. It is equipped with blades made from high-tensile steel that are attached to the rotor at one end and to the housing's inner wall at the other. The machine’s quality features include the rotor with rotating arms, the belt drive with tensioning pulley, the motor and gearbox, the maintenance doors with safety lock and the electrical cabinet with a frequency inverter and adjustable rotor speed.

Testing is a key element of Stadler’s product development process. Trying out the machine in different recycling plants enables the company to integrate feedback from the customers and identify any areas for improvement or tweaks to optimize its performance.

The Stadler delabeler was tested in the United States, Romania and in two recycling plants in Germany. The customers involved were impressed by the difference the delabeler made to their process and all of them purchased the machine once the tests were completed, Stadler says.