Process for extracting oil from contaminated filter media
US5938927A · kind A · utility
4Cited by
17References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 8, 1997 |
| Grant date | Aug 17, 1999 |
| Priority date | — |
| Expiry date | Jul 8, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D11/0203
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Oil and oil additives separated from a contaminated solid particulate filter medium, preferably diatomaceous earth particles. Portions of a mixture of oil, oil additives and the filter medium are compressed into pellets that are extracted with liquid or supercritical CO.sub.2 to form a liquid solution. The solution is separated from the pellets and then heated to 20.degree.-60.degree. C. at a superatmospheric pressure to drive off CO.sub.2 gas, which is preferably recycled by compression into liquid or supercritical CO.sub.2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.