A laboratory workflow to screen nanodroplet additives for enhanced oil recovery from tight rocks. (October 2022)

• Record Type: Journal Article
• Authors: Eghbalvala, Maryam; Yuan, Lin; Habibi, Ali; Dehghanpour, Hassan
• Is Part Of: Sustainable energy technologies and assessments. Volume 53:Part B(2022)
• Publication Date: 2022-10
• Subjects: Renewable energy sources -- Periodicals; Energy development -- Technological innovations -- Periodicals; Electric power production -- Periodicals; Energy storage -- Periodicals; 333.79
• DOI: 10.1016/j.seta.2022.102392
• Languages: English
• ISSNs: 2213-1388

Abstract

Abstract: We present a comprehensive laboratory workflow to investigate different parameters affecting the efficiency of enhancing oil recovery from tight rocks. We used tight-core plugs and nanodroplet (ND) solutions prepared by three complex nanofluid additives which include nonionic surfactants and solvents to conduct our experiments. This protocol is applied in the following steps: (1) Characterizing natural wettability of the core plugs by spontaneous imbibition and contact-angle tests; (2) Evaluating ND-assisted imbibition oil recovery tests under different brine salinities; and (3) Understanding fluid-fluid interactions by evaluating fluid properties, particle size distribution, and stability of the ND samples. The experimental results show that the use of ND additives decreases the oil–water interfacial tension (IFT) and alters the rock wettability towards more water-wet conditions. However, enhanced imbibition oil recovery using ND solutions prepared by the ND additives cannot be sufficiently explained by the IFT reduction and macroscopic CA changes. Generally, increasing fluid salinity reduces oil recovery by the ND solutions, which can be explained by the weaker osmotic potential and the formation of larger particles in high-salinity water. The solubility results indicate that the formation of middle-phase (or near middle-phase) microemulsion is favorable to increase oil recovery.