Influence of Refinery Asphalt Residue Addition on Flow: A Study Using Waxy Model-System

Abstract

One of the main phenomena causing problems in the oil industry is the precipitation of waxes, which can crystallize and form deposits, clogging lines and reducing flows. Many studies have been conducted seeking to overcome this problem, mainly through application of chemical to increase flow. Some studies have shown that the asphaltenes present in crude oil can also be involved in the process of wax deposition. In this study, model systems were investigated to determine the influence of a natural additive, a chemical additive and their combined use on the fluidity of the samples. The natural additive, consisting of a refinery asphalt residue (ASPR), was studied in relation to the influence of its aggregation states on the fluidity of the wax model systems. All samples were evaluated through the pour point test, according to the ASTM D-97 standard. The results indicated that both the ASPR and the commercial poly(ethylene-co-vinyl acetate) can improve the fluidity. Synergistic effect, using both together, was verified by the significant reduction of pour point for model systems with wax content as high as 13% m v-1. That action was closely related to the concentration of ASPR and its aggregation state, as indicated by tests with different wax concentrations.