Method of preparing pyrolysis oil from waste plastics

Abstract

A method for preparing pyrolysis oil from waste plastics, the method including: (S1) feeding a waste plastic raw material to a first reactor, performing primary pyrolysis, and discharging an upper gaseous stream produced by the pyrolysis through an upper portion of the first reactor; (S2) feeding the upper gaseous stream of the first reactor to a distillation column and separating the upper gaseous stream according to boiling point to obtain a stream containing C5-12 light oil, a stream containing C13-22 middle oil, and a stream containing C23 or higher heavy oil; (S3) supplying a portion of the stream containing middle oil separated in the distillation column to a second reactor, performing secondary pyrolysis, and feeding a gaseous stream produced by the secondary pyrosis in the second reactor to the distillation column; and (S4) recycling the stream containing the heavy oil separated in the distillation column back to the first reactor.

Dependencies are inferred from the claim text.