K 2022: Coperion and Coperion K-Tron - High-efficiency technologies for processing and recycling plastics

Another highlight at the Coperion booth will be the STS Mc¹¹ series laboratory extruder with a 25 mm screw diameter. It stands out with its simple design, user friendliness and easy cleaning. Its D_o/D_i of 1.55 and specific torque Md/a³ of 11.3 Nm/cm³ allow for safe scale-up across the entire STS Mc¹¹ series. The STS 25 Mc¹¹ will be exhibited with a Coperion K-Tron K-ML-SFS-KT20 twin screw feeder.

Moreover, the new, preconfigured ProRate PLUS feeder line will be available to view in all three available sizes: small, medium, and large. This continuous gravimetric feeder from Coperion K-Tron is very robust, and thanks to its good price-performance ratio is an economical solution for reliable feeding of free-flowing bulk materials.

The SP series dual bearing strand pelletizers have been given a comprehensive facelift; Coperion’s SP340 model will represent this development at the K booth. In comparison to the previous model, the new SP strand pelletizer allows even faster recipe and color changes. The cutting chamber works with absolutely no dead space; thanks to its quick-release function, the cutting unit can be swapped out quickly and easily. The pelletizer’s interior has improved accessibility and is very easy to clean.

One further highlight of Coperion’s showing at K 2022 will be the ZXQ 800 rotary valve. This high performance valve, which works with especially low gas leakage, was developed by Coperion especially for powder intake into pneumatic conveying lines at up to 3.5 bar. Thanks to its enormous capacity, it is very well suited for systems planned for polyolefin manufacturing in the future.

Plastics Recycling: a Second Life for a Valuable Raw Material

As a raw material, plastic can make a valuable contribution to environmental protection and to the energy revolution. Key to both is the efficient recycling of plastics. For this reason, plastics recycling is the focus of comprehensive development projects at Coperion. The company will show the results of these projects at K 2022 in its pavilion on the open-air fairgrounds (CE09) within the VDMA Circular Economy Forum. There, Coperion will present its combined process solutions and technologies for the economical recycling of various plastics while achieving the highest levels of product quality. At the center will be a system built around a ZSK 58 Mc¹⁸ twin screw extruder configured for manufacturing high-quality PET using recycled materials.

For feeding voluminous flakes and fibers (PET and other plastics) efficiently into the ZSK twin screw extruder, Coperion will show the SWB-300 Smart Weigh Belt Feeder with a S100 single screw pre-feeder, as well as the new ZS-B 70 MEGAfeed side feeder. The SWB is an extremely reliable gravimetric feeder from Coperion K-Tron that can process large volumes of bulk materials with a wide variety of flow properties at very high accuracy. Using the innovative, newly developed Coperion ZS-B MEGAfeed, plastic recyclate with a bulk density under 200 kg/m³, long considered intake-limited and thus not worth recycling, can be reliably fed in large quantities into smaller sizes of Coperion’s ZSK twin screw extruders and be concurrently recycled and compounded.

Melting, intensive devolatilization, and complete homogenization take place in the process section of the ZSK 58 Mc¹⁸, before the material stream is transferred via a gear pump and filter with an automatic screen pack changer to an underwater pelletizer for pellet production. Finally, the pellets are condensed in the SSP (Solid State Polycondensation) reactor and can then be processed again into bottles, fibers, or films. The high quality of recycled PET manufactured using this innovative Coperion process was approved by the U.S. Food and Drug Administration (FDA) for direct contact with food (letter of non-objection).

Conventional technologies for recycling PET require pre-drying and crystallization of flakes and fibers before they can be re-processed. Using Coperion's technological process solution, PET recyclate can be introduced directly into the ZSK extruder. Recyclers profit particularly from the very high end product quality. Thanks to the ZSK’s very good devolatilization properties, volatile components such as monomers, oligomers and water are reliably removed. Savings in operating and logistics costs as well as reduced energy consumption are further advantages of Coperion systems for recycling PET.

If the plastic pellets produced create undesirable odors, these can be reliably removed using deodorization equipment from Coperion. In order to optimize such deodorizing equipment’s specification and to individually determine its operational parameters, Coperion now provides onsite tests using a mobile unit for reducing plastic pellet and recyclate odor at customers’ production facilities. Using this solution with freshly produced product and under actual production conditions, the possibilities for reducing recyclate odor can be thoroughly investigated, and system parameters to achieve desired product quality can be defined on location. Coperion will exhibit this mobile deodorization unit in its Recycling Pavilion (CE09).