Waschanlagen für starre und flexible Kunststoffe Lieferanten

Rigid vs flexible plastic — different processing requirements

Rigid plastic (HDPE, PP, PET) and flexible plastic film (LDPE, LLDPE) have fundamentally different physical characteristics that require different machine designs. Rigid plastic: higher bulk density (300–500 kg/m³), fractures cleanly under granulation, flows freely through conveyors and washers, and is relatively easy to process. Film plastic: very low bulk density (20–80 kg/m³ for loose flake), tangles in rotating equipment, requires wet cutting (wet granulator) rather than dry crushing, and needs high-volume handling equipment sized for volume rather than weight. Density-based separation (float-sink): both PE film and PP/HDPE rigid plastic float in water — density separation alone does not separate rigid from flexible. Hot wash is more commonly needed for post-consumer rigid plastic (bottles with adhesive labels) than for industrial film, but agricultural film may need it too. Because the processing requirements differ, a combined rigid/flexible line is typically a compromise — it may not achieve the optimal output quality for either stream that dedicated purpose-designed lines would. The practical question is whether the available input volume and economics justify two separate dedicated lines or whether a combined approach is more appropriate.