Process for vacuum pyrolysis removal of polymers from various objects
US4220480A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 18, 1978 |
| Grant date | Sep 2, 1980 |
| Priority date | — |
| Expiry date | Sep 18, 1998 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB08B2220/04
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Polymeric organic compounds are pyrolyzed to remove them from objects by heating in a first vacuum chamber to render flowable such polymers as are fusible at a temperature below that at which appreciable degradation is initiated. The fused polymer drops by free fall from the first chamber to a second vacuum chamber through a conduit connecting the two without contacting any intervening structure. The second chamber is maintained at a substantially lower temperature, where the polymer resolidifies. Upon further heating, polymer remaining in the first chamber is volatilized and withdrawn from the chamber to a water mist scrubber where it is largely trapped. Remaining vapors in the scrubber are drawn through a vapor separator to a vent stack. After the combustible volatiles are removed from the first chamber, air is admitted into the chamber to oxidize any residual carbon ash, leaving only the inorganic residue which is easily removable from the objects or materials that were not affected by the pyrolysis action.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.