Understanding the Demulsification of Water-in-Diluted Bitumen Froth Emulsions

Abstract

Demulsification of water-in-diluted bitumen froth emulsions is greatly affected by the presence of solids in the emulsions. In this paper, the wettability, composition, and particle size distribution of the solids extracted from bitumen froth emulsions and diluted bitumen after demulsification, in the absence and presence of a demulsifier, were investigated using partitioning tests, X-ray diffraction, and scanning electron microscopy. It was found that the application of the demulsifier assisted in the removal of water-wet solids, with the main components of the solids in the diluted bitumen being siderite and clays. The median particle size of the solids (D50) was reduced from 8 μm in the bitumen froth emulsions to less than 2 μm in the diluted bitumen phase after the use of a demulsifier in the diluted bitumen froth treatment. The presence of fine solids in the diluted bitumen froth increased the water/bitumen interfacial tension and increased the difficulty of demulsification because the fines are biwe...