Synthesis and Enhanced Oil Recovery Potential of the Bio-Nano-Oil Displacement System

Abstract

Nanoparticles (NPs) have attracted great attention in the tertiary oil recovery process due to their unique properties. As an economical and efficient green synthesis method, biosynthesized nanoparticles have the advantages of low toxicity, fast preparation, and high yield. In this study, with the theme of biotechnology, for the first time, the bio-nanoparticles reduced by iron-reducing bacteria were compounded with the biosurfactant produced by Bacillus to form a stable bio-nano flooding system, revealing the oil flooding mechanism and enhanced oil recovery (EOR) potential of the bio-nano flooding system. The interfacial properties of the bio-nano-oil displacement system were studied by interfacial tension and wettability change experiments. The enhanced oil recovery potential of the bio-nano-oil displacement agent was measured by microscopic oil displacement experiments and core flooding experiments. The bio-nano-oil displacement system with different nanoparticle concentrations can form a stable dispersion system. The oil–water interfacial tension and contact angle decreased with the increase in concentration of the bio-nano flooding system, which also has a high salt tolerance. Microscopic oil displacement experiments proved the efficient oil displacement of the bio-nano-oil displacement system and revealed its main oil displacement mechanism. The effects of concentration and temperature on the recovery of the nano-biological flooding system were investigated by core displacement experiments. The results showed that the recovery rate increased from 4.53 to 15.26% with the increase of the concentration of the system. The optimum experimental temperature was 60 °C, and the maximum recovery rate was 15.63%.

Enhanced Oil Recovery in Low-Permeability Reservoirs Utilizing Dispersions of Monodisperse Crumpled SiO2 Nanoparticle

“…Through microscopic displacement experiments, the process of remobilizing residual oil with a C-SiO 2 dispersion was recorded, elucidating the mechanism of enhancing oil recovery by C-SiO 2 . As shown in Figure a, the synergistic action of the modified C-SiO 2 and surfactants in the dispersion resulted in the emulsification of remaining oil into smaller droplets, improving the fluidity of the remaining oil, and further enhancing the recovery . As shown in Figure b, the remaining oil was emulsified and deformed by wire drawing during the displacement of the C-SiO 2 dispersion liquid.…”

“…As shown in Figure 9a, the synergistic action of the modified C-SiO 2 and surfactants in the dispersion resulted in the emulsification of remaining oil into smaller droplets, improving the fluidity of the remaining oil, and further enhancing the recovery. 32 As shown in Figure 9b, the remaining oil was emulsified and deformed by wire drawing during the displacement of the C-SiO 2 dispersion liquid. With the injection of the C-SiO 2 dispersion liquid, the modified C-SiO 2 was fully in contact with the remaining oil.…”