| 摘要 |
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-water 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. |
