Recycling of plastics

In order to meet the growing needs of the plastics recycling sector, ANDRITZ has developed a very compact recycling system to save transportation and disposal costs and eliminate the damage to the environment caused by burning of plastic waste. Instead, the system recovers plastics as a valuable secondary raw material featuring high purity. The recovered plastic can be used for gray or colored plastic to make new products.

ANDRITZ has combined the ADuro U shredder with an all-in-one solution for separating, washing and dewatering – the CENSOR ACZ decanter centrifuge. This powerful pair is perfect for processing various types of plastic waste, especially from household waste collection.

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A combination of ANDRITZ shredder and separation technology

First step: High-tech shredding

The raw material collected is fed into an ADuro U shredder, an innovative single-shaft shredder that enables one-step processing of hard and soft plastics. The machine is capable of processing bulky materials down to very small particle sizes in a single step. An output size of less than 10 mm is possible thanks to an adaptable screening system. The cutting component of the ADuro U consists of an array of knives positioned both lower and higher and which overlap continually when cutting. This arrangement breaks down the incoming material uniformly and ensures a clean cut.

ADuro U shredder

Second step: Highly efficient separation

The CENSOR ACZ, the core unit of the process, is a sorting centrifuge that separates, washes, and dewaters the raw material all at the same time. The centrifuge is partly filled with a separation liquid (normally water), forming a liquid ring due to high-speed rotation. Intense turbulence within the machine results in deagglomeration of the individual plastic particles and largely frees them from any adhering dirt. Light and heavy solids (fractions) are discharged separately. Whereas the heavy fraction can be further processed or sent to disposal, the light fraction is a highly valuable secondary raw material perfectly suitable for extrusion and injection molding. Depending on the type of plastics to be separated, the CENSOR ACZ achieves purity of more than 99.8% with very low losses of valuable product.