Near-infrared spectroscopy in recycling

In the past, recycling by hand was required to reduce the impact of waste on our environment and loss of valuable resources.

Recycling has become an important subject in today’s society due to the impact of waste on our environment and the loss of valuable resources. Whereas in the past, recyclable materials (e.g. paper, plastics, and textiles) were sorted mainly by hand, the use of near-infrared (NIR) spectroscopy has become a standard in the recycling industry.

One of the most difficult materials to classify in recycling waste streams is plastic. Reflection measurements employing near-infrared spectroscopy enable the classification of many of the most common polymers present in recycling waste streams. Each polymer has a distinctive fingerprint spectra which allows for the identification of recyclable plastics and the elimination of contaminants, which can create downstream problems in the plastic extrusion process.

Modern recycling sorting systems are using NIRLAB NIR spectroscopy to rapidly and automatically identify different plastics and eliminate contaminants.