Plastics sepn. for polyvinyl chloride and polyethylene terephthalate bottles - by sepg. hollow components contacting heated body and with lower softening point w.r.t. various physical properties e.g. elasticity

摘要

The sorting comprises heating the material mixt. to 90-250 deg.C and contacting with a mechanical body. Components with the lowest softening point are sepd. off due to various properties, e.g. elasticity, plasticity, impact behaviour or frictional coefft. A pref. mechanical body comprises a drum (101) with radially projecting pegs (120) round the circumferential surface (105). The pegs (120) penetrate the plastic components (10) with the aid of a feeding device (115). Plant for sorting a mixt. of three or more, in partic. six, different materials may comprise several successive mechanical bodies, opt. combined with existing sepn. processes which are based on density sepn. The plastic components e.g. PVC and PETP are pref. heated to 100-250 deg.C, (150-250 deg.C) esp. 180-230 deg.C. Softer components (10) are penetrated by the mechanical body, the pegs (120) of which exert a given pressure for a defined period. Non-penetrated components (12) are directed to a separate store. Preferred components are accelerated against an impact surface inclined against the direction of the moving components. Components are sorted w.r.t. impact behaviour. Pref. the component mixt. is heated to 100-210 deg.C and contacted with a friction surface which accelerates components with a high coefft. of friction and separates them from those with a lower coefft. of friction. USE/ADVANTAGE - The sepn. is for sorting various types of plastic and is esp. suitable for sorting hollow plastic components e.g. bottles. Sorting of PVC from PETP is obtd. without using organic solvents or fine milling the materials.