| Micropipette techniques were used to directly explore the in-situ behaviour of single emulsion drops. The size of the drops is that typically found in a commercial oil sands operation. All experiments were conducted using an optical microscope. Two different emulsion systems, which are formed during oil sands processing, were investigated.; Initially, interfacial tension measurements and rigidity tests were conducted for water-in-diluted bitumen systems. In general, the interfacial tension on the water droplet surface decreased as bitumen concentration increased. Different solvent mixtures had little effect on the interfacial tension. Furthermore, crumpling of the interface was influenced by bitumen concentration, type of solvent and water pH.; Subsequently, bitumen-in-water emulsions were studied. Bitumen drops were individually stretched in de-ionized water in the presence of montmorillonite clays and/or calcium ions. In general, the surface plasticity of bitumen drops is enhanced when increasing both calcium ion concentration and temperature. |
