Microscopic phenomena inferred from the rheological analysis of an emulsion

Abstract

The rheological behavior of an emulsion is determined by microstructural changes caused by external loads. Some of these changes are irreversible due to the occurrence of the destabilization processes. Therefore, a deeper understanding of the system may be acquired by linking rheological characterization results with microscopic events. It is important to understand the rheological consequences of the occurrence of destabilization phenomena such as coalescence and flocculation. An experimental study was performed to verify the destabilization of samples during shear in a rheometer. Coalescence was assessed by measuring changes in the droplet size distribution functions, while the degree of flocculation was determined with the use of consecutive flow curves. Additionally, the occurrence of the non-equilibrium condition was studied. As a case study, the method developed in this paper was applied to a water-in-oil crude emulsion.