RÜCKGEWINNUNGSVERFAHREN FÜR POLYSTYROL

摘要

This disclosure concerns a process and apparatus for reclamation of waste polystyrene-type materials for reuse within the specification ranges of the input polystyrene-type material. The disclosed process and apparatus include dissolution of the waste polystyrene-type materials in a dissolve section utilizing a reusable solvent having a low boiling point and high vaporization rate, removal of solid contaminants in one or more filter sections, devolatilization of the dissolved polystyrene and recovery of the polystyrene-type material in a solid form in a recovery section. Preferably the process and apparatus provide a closed system and include recycling and reuse in the process of the vaporized solvent. The maximum temperature in the recovery section is 190° C. The reusable solvent is preferably environmentally safe and has a low boiling point and high vaporization rate. n-Propyl bromide, or environmentally safe mixtures thereof, including mixtures with isopropyl alcohol, is the preferred reusable solvent.