DISCRIMINATION AND REMOVAL OF WASTE PLASTIC

摘要

PURPOSE:To classify plastics low in specific gravity difference by judging the functional group of plastic on the basis of the molecular structural formula by the absorption of infrared rays with a specific wavelength or the absorption of near infrared rays with a specific wavelength to classify plastic according to its kind. CONSTITUTION:A receiving and supply conveyor 22 is arranged in the vicinity of a collecting vehicle 21 and waste plastic is charged on the conveyor 22 from the collecting vehicle 21. The waste plastic on the conveyor 22 is judged by the irradiation with infrared rays with a wavelength of 3.5-16mum or near infrared rays with a wavelength of 0.6-2.5mum from a floodlight projector 23. A light signal is converted to an electric signal by a photodetector 24 and the electric signal is sent to an operational control part 25 to judge the kind of the waste plastic and the judgment result is transmitted to the actuator 26 connected to the operational control part 25. The actuator 26 moves the sorting conveyor 27 being a part of the receiving and supply conveyor 22 and polyvinyl chloride falls on the hopper 28 under the conveyor 22 to be removed.