Evaluation of Polymers as a Strategy to Reduce Asphaltene Adsorption on Rock Surface

Abstract

Summary One of the most extensively studied flow assurance issues in the petroleum industry is the precipitation and deposition of asphaltenes. This is in part because of the molecular structure’s intricacy and the interconnected factors that influence and regulate its activity. The injection of inhibitors and dispersants, which affects the economics of crude oil production, is now the most successful strategy for preventing asphaltene problems. Throughout the crude oil supply chain, from the reservoir through the tubing and refinery systems, asphaltene is a concern. However, the area closest to the wellbore, where the highest pressure drop is seen, is the most prone to asphaltene adsorption and deposition. Thus, the goal of this study is to investigate the use of sacrificial fluids to reduce asphaltene adsorption and deposition around the wellbore. To prevent asphaltene from interacting with the rock surface and shifting the asphaltene problem into tubing, where its impact on wettability is low, polymers with functional capabilities are investigated. The performance test (adsorption inhibition capacity), binding energy analysis, adsorption experiments (adsorption affinity, configuration, and mechanism), and fluid characterization (salinity tolerance, surface energy, and interfacial tension) of the selected novel fluids for asphaltene adsorption mitigation are presented. The investigation of ion-specific rock-fluid interactions offers great potential in the search for an effective answer to the asphaltene problem, according to the results. This was proved by the fluid levels of binding energy to carbonate rock samples and their capacity to prevent interactions between asphaltene molecules and the rock surface. These findings provide a fresh perspective on the creation of an economic strategy to deal with asphaltene issues and their effects. This study is the first to investigate a long-term fix for wettability changes caused by asphaltene adsorption on rock minerals. The findings revealed that an optimal concentration exists for the polymers under study, at which the asphaltene interaction is mitigated. More so, surface energy evaluation is observed to be a critical tool that can help to screen polymers for this application. Furthermore, the method of implementation, which could be either squeeze operation or continuous injection, is critical to the success of the remediation.