Method for processing waste material in the form of filter rods, filter cigarettes and the like
US5402893A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 14, 1993 |
| Grant date | Apr 4, 1995 |
| Priority date | — |
| Expiry date | Jul 14, 2013 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA24D3/02
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A method is described for processing waste materials in the form of filter rods, filter cigarettes and the like comprising filter material with inner hollow volumes accessible from the outside and at least one other material component, in particular paper and tobacco, wherein the following process steps are carried out: the waste material is distributed in a liquid in a pressure vessel. By increasing the pressure or decreasing the temperature an inert gas is dissolved in the liquid. Subsequently the temperature is increased or the pressure decreased so that fine gas bubbles develop within the filter material which permits the latter to float whereby a separation from the further material components to be separated is possible. With this method a separation of the waste material into its individual component parts is possible so that for example valuable filter material in the form of cellulose acetate is obtained in highly pure form and can be used again for the production of filter materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.