German sorting technology specialist Sesotec has moved its new VARISORT+ CARBON BLACK system from development to a fully operational MWIR sorting platform, addressing a longstanding challenge in plastics recycling: the detection and separation of carbon-black plastics.

Unlike conventional Near-Infrared (NIR) systems, which can struggle to identify black plastics because carbon black absorbs near-infrared radiation, the new system uses Mid-Wave Infrared (MWIR) technology to detect material-specific spectral signatures.

The technology can identify and separate polymers including PE, PP and ABS, including carbon-black-containing plastics, at a relatively coarse particle size after pre-shredding and before final grinding.

Sesotec transferred its first system from production to its in-house technical centre at the end of June. The company says customers can now test their own material streams under realistic operating conditions.

The system combines MWIR sensing, spectral analysis, intelligent software and established AI models to classify materials and support automated sorting.

By moving the separation of black plastics to an earlier stage of the recycling process, the technology is designed to reduce the amount of material requiring further processing and improve the recovery of individual polymer fractions.

Image credit: Sesotec