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.

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Crude oil generally reaches the platform in a mixture of crude oil and water, among other components. These products flow through valves and pumps, where agitation leads to the occurrence of emulsions. Their presence is undesirable as they lead to an increase in transportation and oil processing costs. Moreover, water content is a factor employed on the benchmark of crude oil prices. Efficiency verification tests for oil processing plants equipment, such as gravity settlers, usually occur with the use of crude oil emulsions obtained in the field. However, such emulsions are fluids that may exhibit toxic, volatile, and flammable behaviors. In this research, we develop a general method for the synthesis of reference fluids intended for replacing crude oil emulsions in gravitational settlers' efficiency verification tests. This method comprises an extensive procedure for mimicking crude systems and their behavior on gravitational settlers. This is achieved by defining key parameters, characterizing some crude systems in relation to these properties and pursuing reference systems with similar characteristic values through an iterative process. A comprehensive theoretical analysis supporting the procedure is also presented. We have also developed two case studies in which materials, experimental protocols, and emulsification techniques that could be employed are described. Furthermore, the reference fluids obtained in these case studies are benchmarked in relation to their crude systems counterparts. In general, our reference fluid for A-crude systems presented valuable results.

Through years of working with visualization studies on micromodels and Hele-Shaw cells, we have always been confronted with difficulties such as numerous images of long flooding processes to be analyzed, irregularities of laser-etched micromodels that complicate the analysis of pore images, poor lighting, and so on. Finally, we aimed to customize a simple method addressing our difficulties. The method is based on singular value decomposition coupled with contour tracing and is developed using the MATLAB programming language. It is built with an approach that allows easy application of the experience of an expert when it is needed. Singular value decomposition (SVD) has been utilized because of its attractive properties that are useful to our objectives, including image compression and image denoising. The method is experimented on pore-scale visualization of polymer flooding in a micromodel, and it showed a reliable performance. In this paper, the pore-scale analysis is chosen rather than calculating the overall oil recovery factor because it has more details to investigate and helps better to evaluate the performance of the proposed method. We calculated the residual oil and connate water saturation as a case study. The method's unique procedure and features are explained step by step through the case study. The method facilitates the analysis by reducing the calculation time and the required storage space. Also, it offers an interesting component to decrease redundancies due to lighting problems.

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