On-line Imaging Based Spectroscopy and FT-IR Based Techniques for Ceramic Glass Contaminants Identification in Cullets Recycling

摘要

The presence of ceramic glass contaminants in glass recycling plants reduces production quality and increases production costs. In fact, at sorting plant scale ceramic glass looks like normal glass and is detectable only by specialized personnel. In this paper an innovative approach for ceramic glass recognition, based on spectroscopic techniques, is proposed and investigated. In order to define suitable inspection strategies for the separation between useful (glass) and polluting (ceramic glass) materials, samples of glass and ceramic glass presenting different color, thickness, shape and manufacturing have been selected. Reflectance spectra have been obtained by imaging based spectroscopy covering the visible (VIS) and the near infrared (NIR) fields, whereas absorbance spectra in the mid-infrared (MIR) wavelength range have been detected by FT-IR spectroscopy. Results showed as recognition of glass and ceramic glass is possible for both the visible and infrared fields.