Plastics separation and recycling methods

摘要

Plastics fragments including polyethylene terephthalate and polyolefins derived from comminution of containers such as beverage bottles are segregated according to specific gravity by flotation. The flotation liquid includes a surfactant to facilitate complete separation of the light and heavy plastic fractions from one another. The surfactant may be a residue of a detergent used to wash the flakes and remove contaminants therefrom. Rinsing prior to flotation separation is controlled so as to leave the desired detergent residue leading to a marked reduction in rinse water requirements.