Enhancement of recovery of residual oil using a biosurfactant slug

Abstract

A laboratory investigation of the mobilization and displacement of residual oil in a sand-pack using biosurfactant slug was conducted. The biosurfactant employed was extracted from a culture of Pseudomonas sp. grown on kerosine- supplemented mineral salts medium. Characterization of the biosurfactant extract revealed a mixture of glycolipid and phospholipid in a ratio of 3.35:1. The irreducible water saturation (S_wi) and initial residual oil saturation (S_or) of the sand-pack were 0.280 ± 0.003 and 0.373 ± 0.006, respectively. Core flooding experiment showed that an optimum oil recovery of 52.19% of the in-place residual oil was achieved at biosurfactant incubation time (BIT) of 120 h. These results suggest that biosurfactant produced by Pseudomonas species is a potential “candidate” for microbially enhanced oil recovery.

Keywords: Laboratory investigation, enhanced oil recovery, biosurfactant slug, Pseudomonas species