When it comes to pelletizing of PET, an energy saving process as well as a certain degree of crystallization is very important. When a customer approached ECON with this requirement, the technological leader and trusted development partner started to design an underwater pelletizer especially adapted to these requirements. The result is the ECON PET-Edition, which has been optimized for PET. With the help of the ECON patented thermal insulation technology, a safe start-up process is obtained. By preventing heat transfer from the die plate unit into the process water, not only is the freezing of die holes prevented, but a considerable amount of energy is saved. In addition, special attention has been paid to an appropriate insulation of the water tank and the piping in order to achieve an end temperature of the pellets of at least 140°C. Depending on the customer's requirements, ECON provides a tailor-made solution to ensure the required pellet end temperature. Not only is the pelletizer engineered to operate with minimum energy consumption, so the downstream equipment - the ECS (ECON Crystallization System for PET). This uses the intrinsic heat of the pellets for crystallization and is therefore one of the most efﬁcient methods of crystallizing PET. The system is designed to keep the PET pellets at a constant temperature and to achieve a degree of crystallization of 30 – 40 %. In the crystallization channel, the pellets are conveyed further by gentle vibration and mixed to prevent sticking during crystallization. The high degree of crystallization enables a faster pre-drying of the pellets before further processing (e.g. injection molding), which saves a considerable amount of time.
Low acetaldehyde content
In the food sector, a low acetaldehyde content of recycled PET is required in order to be able to meet the legal guidelines. "Our goal in the development of the ECON PET-Edition was to achieve a significantly improved value in comparison to conventional pelletizing systems," explains Dominik Neumann, team leader of the R&D department. Together with the customer, we worked intensively on an efficient solution. By reducing the pressure build-up at the die plate by 40 %, a low acetaldehyde content of 30 - 40 % was achieved directly after pelletizing. Previous tests have shown that a lower energy input can be expected during dehydration, since the reduced acetaldehyde content represents a different starting position.
The ECON PET-Edition is a very energy-efficient solution for pelletizing rPET/PET and thus contributes to the circular economy. " When it comes to PET recycling, the kW/t of recycled material has a signiﬁcant impact on the proﬁtability of the production line. This means that using the ECON Technology results in a signiﬁcant competitive advantage”, says Gerhard Hemetsberger (Head of Sales). ECON always focuses on a tailor-made solution, based on the individual requirements of their customers.
K 2022: LIVE Demonstration
At K 2022, the PET-Edition will be displayed in a fully automated version during a live demonstration. Another highlight is the new EWFP (ECON Water Filtration Professional). The filter achieves a grade of filtration up to 55 µm and allows a fully automatic and maintenance-free operation. Besides the running equipment, the pyrolysis furnace - EPOS - specially developed for extruder screws will be exhibited. Visit ECON in hall 9, booth # C30!