COMPARISON OF OIL RECOVERY FOR SIX NANOFLUIDS IN BEREA SANDSTONE CORES

摘要

Recent studies have shown that using nanofluids (nanoparticles suspended in fluids) in a way similar to water flooding shows promise as a new enhanced oil recovery (EOR) technique. The objective of this study was to determine the optimum nanoparticle morphology and particle size for EOR while gaining insight into the mechanisms driving the system. The tests were conducted at ambient conditions using core flooding analysis. Water wet, high permeability (avg. K ≈ 362 mD) Berea sandstone cores (length 13 cm and diameter 3.8 cm) were used for the testing. Hydrophilic nanoparticles and nano-structured particles were suspended in a synthetic North Sea water solution at 0.05 wt %. The two different types of hydrophilic nanoparticles were nano-structured fumed silica dispersions and colloidal silica. Three particle sizes were tested for each of the nanoparticle types, resulting in a total of six nanofluids used for analysis. The nano flooding was conducted as a tertiary EOR method after secondary water flooding. Interfacial tension and contact angle measurements were performed to better understand the mechanisms.