Method of separating plastic
US6415929B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 18, 2001 |
| Grant date | Jul 9, 2002 |
| Priority date | — |
| Expiry date | Apr 18, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/62
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
When plastic pieces of plural different types of resins fed into a hopper are agitated to be triboelectrically charged, the plastic pieces are not imparted with sufficient amounts of charges or proper polarities which are required for separation of the plastic pieces if there are great differences in quantity between the different types of plastic pieces. This makes it impossible to properly separate the plastic pieces. Where the amount of pieces of a particular plastic to be separated is small, pieces of the particular plastic are additionally fed as a triboelectrification agent into a triboelectric charger (3) and agitated with the plastic pieces. Thus, different types of plastic pieces (1) (e.g., PVC and PE) are prevented from being imparted with the same polarity and are imparted with different amounts of charges, so that the separation can assuredly be carried out in an electrostatic separating section (G) for recovery of the particular plastic pieces.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.