METHOD FOR GRANULATING GRANULATED MATTER OF POLYETHYLENE AND POLYPROPYLENE FROM WASTE PLASTIC

摘要

PROBLEM TO BE SOLVED: To granulate PE and PP granulated matter from waste plastic. SOLUTION: A film-like plastic is crushed into a particle size of 10 mm or less by a crusher 1 to be transferred to a melting granulator 3 by a blower 2 and the crushed plastic is heated to 120 deg.C or higher equal to or higher than the m.p. of PE by generated friction heat and an auxiliary heater while a specific gravity soln. is stirred by a stirrer 7. The PE separated by specific gravity difference is melted and cooling water is sprayed on the molten PE from a cooling water blowoff nozzle 4 to be cooled and granulated and PE granulated matter, PP and chlorine-containing plastic are transferred to a wind force sorter 6 to be separated to recover PE granulated matter. The PP and chlorine- containing plastic separated from the PE granulated matter are again transferred to the melting granulator 3 and the temp. of them is raised to about 180 deg.C equal to or higher than the m.p. of PP and PP separated by specific gravity difference in the same process is solidified in a granular form and PP granulated matter and chlorine-containing plastic are separated in the same way by the wind force sorter 6 to recover the separated PP granulated matter.