The invention relates to a method and
system for recycling waste plastics, and the method comprises the steps that S1,
solid waste plastics and replacement gas enter a deoxidation device, so that the replacement gas conducts purging deoxidation treatment on the
solid waste plastics, deoxidized plastics are obtained, and the deoxidation device comprises a gas stripping functional area and a
diffusion functional area which communicate with each other; s2, the deoxidized plastic enters a
softening-dechlorination device to be subjected to
softening-dechlorination treatment, and
chlorine-containing gas and softened dechlorinated plastic are obtained; s3, the softened dechlorinated plastic enters a liquefying device to be subjected to liquefying treatment, and
pyrolysis gas and liquid plastic are obtained; s4, enabling the
chlorine-containing gas in the step S2 and the
pyrolysis gas in the step S3 to enter an alkali washing device for alkali washing treatment; and at least part of the liquid plastic in the step S3 serves as a circulating material to be heated and then returns to the liquefying device to be continuously treated. The present disclosure can significantly reduce the yield of by-products and continuously and stably provide a liquid feed for waste plastic
pyrolysis.