Injection of biosurfactant and chemical surfactant following hot water injection to enhance heavy oil recovery

Abstract

This study investigates the potential of enhancing oil recovery from a Middle East heavy oil field via hot water injection followed by injection of a chemical surfactant and/or a biosurfactant produced by a Bacillus subtilis strain which was isolated from oil-contaminated soil. The results reveal that the biosurfactant and the chemical surfactant reduced the residual oil saturation after a hot water flood. Moreover, it was found that the performance of the biosurfactant increased by mixing it with the chemical surfactant. It is expected that the structure of the biosurfactant used in this study was changed when mixed with the chemical surfactant as a probable synergetic effect of biosurfactant-chemical surfactants was observed on enhancing oil recovery, when used as a mixture, rather than alone. This work proved that it is more feasible to inject the biosurfactant as a blend with the chemical surfactant, at the tertiary recovery stage. This might be attributed to the fact that in the secondary mode, improvement of the macroscopic sweep efficiency is important, whereas in the tertiary recovery mode, the microscopic sweep efficiency matters mainly and it is improved by the biosurfactantchemical surfactant mixture. Also as evidenced by this study, the biosurfactant worked better than the chemical surfactant in reducing the residual heavy oil saturation after a hot water flood.

The crude oil biodegradation activity of Candida strains isolated from oil-reservoirs soils in Saudi Arabia

“…On the other hand, ionic precipitation had almost the same number of yields. That might be due to the fact that the emulsi cation activity of an organism depends on the pH and divalent cations such as magnesium ions [51]. In agreement with our ndings, the amount of rhamnolipid biosurfactant produced by Pseudomonas aeruginosa was higher when produced by organic solvent extraction (7.37 ± 0.81 g/L), which was higher than the amount produced by zinc sulfate precipitation (5.83 ± 0.02 g/L) [52].…”

“…These biosurfactants are amphipathic compounds, which possess both hydrophobic and hydrophilic moieties and exhibit various amphiphilic structures [49]. In accordance with our ndings, previous studies showed that biosurfactants recovery depended mainly on its ionic charge and solubility in the desired solvent, which might explain the different yields produced by isolated strains [8, 49,51].…”

A Review on Biosurfactant Applications in the Petroleum Industry

“…e EOR methods mainly include injecting a particular fluid with chemical, thermal (in situ combustion, injecting steam), or microbial characteristics into the reservoir [21,23,37,[49][50][51][52][53]. omas provided a detailed classification of EOR methods [54].…”

Consideration of Application Possibility of Biosurfactant and Alkaline-surfactant-polymer (B-ASP) with Ultra-low Crude Oil/Brine Interfacial Tension for Enhancement of Oil Recovery

“…Thus, they were mutually attractive in the monomolecular layer of the mixed interface despite possessing negative charges in their molecules. Al-Wahaibi et al 26) prepared a surfactant mixture composed of the lipopeptide produced by B. subtilis and a chemical surfactant, i.e., ethoxylated sulfonate, and found significant improvement in the interfacial performance. With their keen observation of the synergy between lipopeptide and ethoxylated sulfonate in the enhancement of oil recovery, the authors concluded that the structure of the biosurfactant altered when it was adopted in combination with a chemical surfactant.…”

“…It was found that the biosurfactant changed the wettability of sandstone to a hydrophilic attribute, which was an important mechanism for scaling on-site application to improve oil recovery 25) . When the ethoxysulfonate surfactant, S-8B, was mixed with lipopeptide in a ratio of 50 : 50, the saturation of residual oil was reduced to 34 % after hot water flooding 26) . It is well documented that the use of two or more surfactants can effectively compensate for the deficiencies encountered in the use of a single surfactant, and may additionally improve the flexibility of performance optimization and allow for the combination to be fine-tuned to compensate for any quality changes that may occur in either surfactant 20) .…”