Method for processing oil refining waste
US5928522A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 17, 1997 |
| Grant date | Jul 27, 1999 |
| Priority date | — |
| Expiry date | Nov 17, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10G53/02
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Refinery waste feedstock is screened to remove large particles and is diluted to less than 5% solids weight percent to form a slurry. The slurry is agitated and heated to 180.degree. F. or higher for a time sufficient to melt waxy petroleum solids, reduce the viscosity of the slurry, reduce the density of petroleum fractions within the slurry, and begin to break surface adhesion of petroleum to residual fines. The conditioned slurry is passed through a first disc/bowl centrifuge which separates more than 80% of the waste volume as a first liquid effluent containing most of the petroleum fractions from the original waste and which may be returned to the refinery for processing. The residual cake is diluted with hot water to form a second slurry and is treated with an amount of hydrogen peroxide for a time sufficient to lyse and/or liberate residual petroleum bound to inert fine particles and to oxidize toxic polycyclic aromatic hydrocarbons to non-toxic derivatives. The second slurry is passed through a second disc/bowl centrifuge, yielding a second liquid effluent which may be combined with the first liquid effluent. The residual cake, containing about 0.5% or less petroleum and ab…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.