Near-infrared (NIR) optical sorting

NIR is one type of optical sorting technology that enables plastic packaging to be separated by polymer type into different plastic recycling streams. It is already used in Germany, with other countries planning to introduce it soon.

Similar automated technologies for sorting plastics include Fourier-transform spectroscopy and optical color recognition systems.

Efficient separation remains a challenge due to different shapes and formats of plastic packaging, labels, coatings, and inks that can slow or impede analysis. One element of designing packaging to be recyclable is to facilitate better sorting of materials.