TREATING METHOD FOR PLASTIC WASTE

• Main Authors: HINO KOICHI, UEMURA FUMIHIKO, MORIYA NOBUO, SAKASHITA KOJI, KOSHIRO MASAZUMI
• Format: Patent
• Language: English
• Published: 26.01.1999
• Edition: 6
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMISTRY; COMPOSITIONS BASED THEREON; DISPOSAL OF SOLID WASTE; GENERAL PROCESSES OF COMPOUNDING; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; RECLAMATION OF CONTAMINED SOIL SOIL; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WORKING-UP

PROBLEM TO BE SOLVED: To recover a valuable matter from a hydrocarbon-derived plastic waste at a high thermal efficiency by bringing a plastic waste contg. hydrocarbon-derived plastics and non-hydrocarbon-derived plastics into contact with a fractionation solvent comprising a specific mixture of hydrocarbon oils to dissolve the hydrocarbon-derived plastics, separating the resultant soln. from solid substances, then subjecting the soln. to concentration, decomposition. and distillation, and circulating a simultaneously produced vaporous distillate. SOLUTION: The plastic waste is brought into contact with a fractionation solvent contg. 5-70% arom. hydrocarbon and 5-85 wt.% paraffinic hydrocarbon to dicssolve the hydrocarbon-derived plastics to thereby separate solid substances comprising the non-hydrocarbon-derived plastics; the resultant solvent soln. is concenterated by bringing it into contact with an oil vapor formed at the decomposition step; and the resultant thermally concentrated liq. is thermally decomposed to give a decomposition-formed oil vapor and a residue oil. A vapor distillate from the concentration step is subjected to distillation, and a part of the distillate is used as the fractionation solvent and the rest is recovered as a valuable matter.