Effect of asphaltene flocculation size on deposition using a modified quartz crystal microbalance in-house setup and microscopic image analysis: Model oil, inhibitory and nanoparticle solutions case studies

Abstract

Asphaltene deposition phenomenon is a challenging event that may occur during the oil production process, causing difficulties such as formation damage and wettability alteration. To overcome these challenges, inhibitors and nanoparticles are commonly used as treatments. The size of asphaltene flocculation is a critical factor in the deposition process. In this study, we investigated the effect of asphaltene flocculation size on deposition using the quartz crystal microbalance (QCM) method in both model oil and inhibitory solutions containing Linear alkylbenzene (LABs), Sodium laureth sulfate (SLES), and 4-Dodecylbenzenesulfonic (DBSA), as well as solutions with nanoparticles such as TiO2 and SiO2. A novel in-house setup was designed to overcome experimental challenges and microscopic images were used as a visual approach for better interpretation of results. Our findings showed that TiO2 and SLES had the greatest performance in postponing flocculation points among nanoparticles and inhibitory solutions, respectively. We also observed that inhibitors were more effective in delaying the flocculation point as the concentration of heptane in the model oil decreased, with a weakened effect at higher heptane concentrations. Based on the interaction of forces, we obtained an average surface area of 17.5 square micrometres as the required value for aggregate deposition. Furthermore, inhibitory solutions showed a much lower growth rate and smaller aggregates compared to normal solutions.