Experimental Evaluation Method of Asphaltene Deposition Inhibitor?s Efficacity at Atmospheric Pressure Using a Fully Immersed Quartz Crystal Resonator, Centrifugation, and Optical Microscopy Techniques

The objective of this paper is to propose a multiscale method to evaluate the effect of additives on the destabilization and deposition of asphaltenes under the conditions of nondiluted crude oil samples. This study shows the results of probing asphaltene deposition in the presence of a chemical additive using a quartz crystal resonator fully immersed in a dead oil while n-heptane is continuously added. The results obtained show that destabilization is slightly delayed and the deposited amount is significantly decreased at concentrations above 3000 ppm of asphaltene deposition inhibitors. The amount of deposited asphaltenes decreases while the inhibitor concentration is increased. In addition, the effect of the chemical is further studied by the centrifugation technique to evaluate the concentration of unstable asphaltene aggregates, and the kinetics of aggregation is investigated under optical microscopy observation. The results support those obtained using a quartz crystal resonator and the rule on the evolution of the size/shape of the aggregates.

Automated summary

The objective of this paper is to propose a multiscale method to evaluate the effect of additives on the destabilization and deposition of asphaltenes under the conditions of nondiluted crude oil samples. This study shows that the presence of a chemical additive slightly delays asphaltene destabilization and significantly decreases the deposited amount at concentrations above 3000 ppm. The effect of the chemical is further studied using the centrifugation technique and optical microscopy observation.