Abstract

This investigation considers black liquors (BL) as candidates for chemical enhanced oil recovery (EOR) process. These BLs were effluents from paper mills. The main constituent of BL is sodium lignosulfonate, an anionic surfactant. Results show that these anionic surfactants may be the preferred candidates for EOR as they may be effective in creating low interfacial tension (IFT) at dilute concentrations without requiring an alkali or a co-surfactant. Some of the formulations exhibit a low IFT at high salinity, and hence may be suitable for use in high saline reservoirs. Adsorption tests were conducted on core samples whichindicate that the loss of these formulated surfactants may be comparable to other types of anionic surfactants. Evaluation of surfactants performance was done in oil recovery by core flood tests. Selected formulations recovered about 20-30% of the waterflood residual oil saturation even with dilute concentration of 0.18 wt% surfactant concentrations from core samples.

Keywords: Black liquor; sodium lgnosulfonate; Low interfacial tension; Enhanced oil recovery; Surfactant adsorption; Chemical flooding