Method for extraction of bitumen from oil sands using lime
US7931800B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 14, 2008 |
| Grant date | Apr 26, 2011 |
| Priority date | — |
| Expiry date | Oct 6, 2028 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10G1/047
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
In a method for enhancing the efficiency of bitumen recovery from oil sands ore, CaO lime (or Ca(OH)2) is mixed into an oil sands ore-water slurry prior to or during the operation of slurry-based bitumen extraction processes. The lime is introduced at dosages effective to reduce the electro-chemical attraction between clay particles and bitumen in the slurry, thereby promoting detachment of clay particles from bitumen droplets in the ore-wafer slurry. This occurs because water-soluble asphaltic acids formed at the bitumen-water interface act as surfactants which reduce or eliminate the activity of Ca2+ and Mg2+ ions binding the clay particles and bitumen together. The detachment of clay particles promotes the attachment of air bubbles to the bitumen droplets, thereby forming a bitumen-rich froth which will float to the surface of the ore-water slurry, thus facilitating bitumen recovery.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.