Mechanical pre-processing of automotive production waste can significantly simplify downstream metal separation and plastic recycling. In this technical case study, we analyse the processing of a mixed waste stream containing polyamide components, steel inserts and springs. We evaluate how the individual components behave during shredding and demonstrate the conditions under which the material can be effectively prepared for magnetic separation.

Aluminium stamping offcuts often have a very low bulk density. Long strips tend to become entangled inside containers, creating large voids and making storage and transport inefficient. During a shredding trial, we evaluated how the material changed after processing in a twin-shaft shredder. The result was short, compact fragments with a bulk density of approximately 590 kg/m³.

Kia Slovakia's engine plant in Žilina is an example of highly automated and precise production, where an effective solution for processing technological waste becomes a key element of operational stability. The article shows how centralized crushing of steel chips in both continuous and single-shift operation contributes to higher safety, lower costs, better logistics and sustainable resource management within the Hyundai Motor Group.

A modern passenger car contains up to 300 kilograms of plastic. However, recycling it is not easy—different types of plastic are often bonded to metal parts and frequently transported over long distances. That is precisely why shredding plays a significant role in reducing logistics costs and increasing recycling efficiency. In a field test conducted by CASTULIK, the DX160 twin-rotor shredder successfully handled even one of the most problematic car parts—the plastic fuel tank.

Company DETOX has long been one of the most reliable providers of hazardous waste collection and processing services in Slovakia. In 2023, the company expanded its Trnava facility with a twin-shaft shredder DX160/600 (18.5 kW) – their third CASTULIK shredder purchased since 2003.

During locomotive wheel repairs at the Czech Railways Cargo workshop in České Budějovice, long steel turnings were produced in large volumes, filling entire storage areas and driving up the cost of transport for recycling. With the introduction of the DR120/600 shredder, the turnings density increased ten times, allowing the company to free up hangar‑sized space and significantly reduce logistics costs.

Knife mills offer a precise and energy‑efficient alternative to traditional single‑shaft wood shredders. Thanks to their small shear gap, high rotor speed, and close proximity of the knives to the screens, they produce fine, homogeneous shred with a low dust content. In contrast, single‑shaft shredders excel in robustness and resistance to metal contaminants, but they achieve poorer results when processing fine fractions, wet wood, or fibrous materials. The choice of technology therefore depends on the type of wood, the required particle size, material cleanliness, and performance demands. The optimal solution is best confirmed by practical testing of your specific material on both types of machines.