Method for removing hydrocarbon contaminants from solid materials
US5454878A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 17, 1994 |
| Grant date | Oct 3, 1995 |
| Priority date | — |
| Expiry date | Feb 17, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S203/17
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A system for removing hydrocarbons from solid materials. Contaminated solids are combined with a solvent (preferably terpene based) to produce a mixture. The mixture is washed with water to generate a purified solid product (which is removed from the system) and a drainage product. The drainage product is separated into a first fraction (consisting mostly of contaminated solvent) and a second fraction (containing solids and water). The first fraction is separated into a third fraction (consisting mostly of contaminated solvent) and a fourth fraction (containing residual solids and water). The fourth fraction is combined with the second fraction to produce a sludge which is separated into a fifth fraction (containing water which is ultimately reused) and a sixth fraction (containing solids). The third fraction is then separated into a seventh fraction (consisting of recovered solvent which is ultimately reused) and an eighth fraction (containing hydrocarbon waste).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.