Sensor based sorting is one of the physical separation technology, which detects physical properties of a moving object without contact, identifies its material instantaneously by analyzing the detected information, and separates it mechanically according to the identification result. This separation technology can handle relatively large particles of nonferrous metal, alloy, plastic, glass, paper, wood etc. Recently, social interest in this technology has been growing because various sensors and data analysis devices have been rapidly upgraded. In this review, recent trends of the sensor based sorting in resource recycling are summarized based on the sensor types of NIR, Optical, XRT, XRF, LIBS, Laser 3D etc. The contents of this review are mainly referred from the proceedings of Sensor Based Soring 2012 that is one of the renowned international conferences on this technology.
