Avaliação da compatibilidade de petróleos quanto à precipitação de asfaltenos e parafinas e os efeitos sobre a viscosidade.

Abstract

A problem commonly faced in production, transportation and refining of petroleum is the formation of deposits of asphaltenes, waxes, hydrates and organic solids in wells, production tubbing and transportation pipelines, separators and refining equipment as result of changes in composition, temperature and pressure. These deposits threaten the flow of the oil fluids from the reservoir to the surface and to the refinery. They harm production and cause damage to the equipment. From the concern in drawing strategies to minimize this problem emerged the concept of flow assurance. The great need for investment and high operating costs associated with the prevention and remediation of these deposits has created a need for methods and modeling capable of predicting precipitation in order to optimize and improve the techniques used in operations, minimizing the risk of formation of these deposits (AKBARZADEH, 2012). Another common problem in the oil industry is the difficulty of processing and transporting heavy oils due to their high viscosity and tendency to form large deposits of precipitates. An alternative usually used is to mix these heavy oils with lighter oils in order to produce a "new oil" with better rheological properties. However, such mixtures can cause undesired precipitation of deposit forming compounds such as asphaltenes and waxes. The objective of this work is to evaluate the compatibility of oils based in asphaltene and wax precipitation. Incompatibility is defined here as the tendency of the mixture to form precipitates. It was also evaluated the contribution of the blend composition to asphaltenes and paraffins precipitation, as well as for the viscosity and °API of the blend.