PURPOSE: To certainly classify and recover specific plastic by performing a process classifying and recovering specific plastic from a system wherein various plastics are mixed.
CONSTITUTION: When stones, iron pieces and wood pieces are manually removed from a mixed system, an ETFE film is charged in an aqueous soln. (density; 133g/cm2) containing of iron sulfate (inorg. salt) 30% and a surfactant 0.2% and washed by an ultrasonic washing machine without generating foam. Herein, iron pieces or small stones incapable of removed manually and having density larger than the aqueous soln. are settled and removed and a string or PVC low in density is removed by flotation. The strength of the washing machine is controlled so that the ETFE film is convected to the intermediate tank of the aqueous soln. by the convection due to the washing machine. The ETFE film is transferred from the intermediate tank where ETFE film is present in much quantity to a classifying tank and the fine iron pieces, a stone powder and the like incapable of being removed in the washing process are settled and removed and PVC or strings are removed by flotation. The classified ETFE film is washed and dried.
ISHIZAKI YOSHIAKI
TOBIYO YOSHIKUNI
