Near-infrared Hyperspectral Imaging Applied to Recycling of Post-consumer Polyolefins

New analytical inspection strategies, based on hyperspectral imaging in the NIR field (1000-1700 nm), have been investigated and set up in order to define quality control logics that could be profitably applied, in “on-line” architectures, at industrial plant level for PO recycling. HSI technique has been applied in order to identify PP and PE from complex waste streams constituting the feed of an innovative separation approach, based on MDS. PE and PP products have been selected on the base of their density and colour, by multi-stage-density-separation. Results showed as HSI allows to perform a recognition of the different density classes of materials, identifying the real cut density between PE and PP and the particle colour distribution. Further investigations will be carried out to evaluate the possibility to classify also dark/black particles, characterised by poor reflectance properties