PETpla.net Insider 07+08 / 2020

INSPECTION 25 PETplanet Insider Vol. 21 No. 07+08/20 www.petpla.net Closing the PET cycle with sorting and material analysis systems Europeans produce 25 million tonnes of plastic waste every year. Worldwide, 78 million tonnes of plastic waste are produced annually. The world as a whole must react to this global problem, because so far recycling rates are at a low level everywhere: in Europe at 30%, in China at 25% and in the USA at only 9% (plastic waste statistics 2017). INSPECTION Large parts of the alleged waste are still being incinerated or end up in landfills and in the environment, thus posing risks to water, air, animal life, health and the food chain. In order to achieve a circular economy, Sesotec states that it is important that all players make their contribution to this task: from product design and manufacture by the plastics industry, through conscious use and waste avoidance or waste separa- tion by consumers, followed by proper recycling and sorting by the waste and recycling industry, to conversion into high-quality secondary raw materials and their use in the manufacture of new products. A prime example that already shows how a recycling economy can function is PET. Bottle sorting system PET recyclers face the challenge that the quality of the input material varies greatly. Poor material quality often leads to reduced throughput, higher loss of good material, poor purity of the sorted fractions and frequent plant downtimes for clean- ing and maintenance. Each of these factors has a negative impact on the efficiency and thus the profitability of sorting and recycling processes. Variosort+ sorting systems detect and sort plastic types, colours, shapes, metals and other foreign objects from the product stream. The material throughput is up to 8 t/hr. Thanks to the intelligent machine design, clean- ing work can be carried out quickly and maintenance requirements remain low. Flakes sorting PET flakes can still contain metal particles, colour impurities and for- eign plastics such as PVC, which are then recycled during further process- ing. If these recyclates are used the impurities can get into the melt and be the cause of costly breakdowns, e.g. during injection moulding of pre- forms. Incorrectly coloured particles impair the colour of the “new” bottles, thus protecting processing machines from damage and ensuring perfect product quality. Quality analysis of PET flakes For manufacturers and proces- sors of plastic flakes, ensuring high material quality is a decisive factor for profitable sales and use of recycled plastic. Depending on the use of the recyclate, and to evaluate the recycling sorting process, the quality of material batches often has to be assessed with elaborate manual, visual or thermal random sample analyses. This causes additional effort, high costs, loss of time and a low representativity of the random samples. With the mate- rial analysis system Flake Scan, the plastic flakes quality can be precisely determined according to plastic types, off-colours and metal foreign bodies, done in a few minutes. The automatic and reproducible analysis of material samples is carried out by up to three integrated sensors: colour sensor, NIR sensor, metal sensor. The effort for manual, visual and thermal analysis can be reduced and a fast and resilient decision can be made about the profit- able use of plastic flakes. Furthermore, conclusions can be drawn about the recycling process and the function of various components. Michael Perl, Group Director Sales Division Sorting Recycling at Seso- tec, says: “Recycling management is a complex task. Our sorting solu- tions and material analysis systems are indispensable building blocks for recycling companies to produce high- quality secondary raw materials. In this way, we are helping to move one step closer to the goal that sustain- ability, profitability and environmental protection go hand in hand”. www.sesotec.com With the flexible Variosort+ sorting systems, products made of PET and other (plastic) materials are said to be sorted efficiently, flexibly and profitably.