Janusz Sikora

1. Introduction The management of polymer waste remains a critical environmental challenge, as the most widely used polymers are non-biodegradable. The increasing production and consumption of polymer-based materials necessitates the development of responsible waste management strategies. In 2020, of the nearly 30 million tons of post-consumer polymer waste collected, only 35% was recycled, 42% was used for energy recovery, and 23% was landfilled [1].

1 INTRODUCTION The screw extruder is the workhorse of the polymer processing industry. The vast majority of the 400 million tons of polymers produced annually go at least once in their lifetime through an extruder. The pelletization process, after the polymerization reactors, is usually carried out with the help of twin-screw extruders.

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