摘要 |
<p>PURPOSE: To classify plastics into various kinds of quality by providing a specific gravity classification device which classifies waste plastics into two or more kinds by difference of specific gravity and a cryocrushing classification device which classifies one group of classified matters by utilizing difference in brittle temperature and crushing them. CONSTITUTION: A classifying system 2a for classifying a waste plastic 1 by material quality consists of a specific gravity classification device 3 and a cryocrushing classification device 4. The waste plastic 1 which is put into the specific gravity classification device 3 is classified into PVC, olefin, and styrene by specific gravity. The PVC is classified into a line of an arrow 102, the styrene is classified into a line of an arrow 103, and the olefin is classified into a line of an arrow 104. Only the line 104 is put into the cryocrushing classification device which is set to a brittle temperature of PP, cooled, and PP and PE are recovered. Thus, four kinds of the PVC, the styrene, the PP and the PE are classified. Thus, the waste plastic 1 can be efficiently recovered as a recycling material of various kinds.</p> |