文摘
This paper is an extension of the work of Grubb et al. [Two-dimensional ethanol floods of toluene in homogeneous, unconfined aquifer media, in: J.C. Evans (Ed.), In-Situ Remediation of the Geo-environment, GSP No. 71, ASCE, NY, 1997, p. 255; Mobilization of toluene in layered, unconfined aquifer media during ethanol flooding, in: P.S.S. Pinto (Ed.), Environmental Geotechnics: Proceedings of the Third International Congress on Environmental Geotechnics Lisboa, Portugal. Balkema Rotterdam Brookfield, 7–11 September 1998] on the recovery of lighter-than-water non aqueous phase liquids (LNAPLs) from sandpacks. Dodecane, toluene and octane (500mL each) were used to simulate fresh and weathered petroleum spills. The ethanol flooding experiments evaluated the feasibility of recovering the LNAPLs from unconfined uniform sandpacks in a quasi two-dimensional apparatus. A combined pure ethanol and 50/50 (vol. % ) ethanol–water blend flooding strategy successfully mobilized and recovered the simulated large-volume LNAPL spills (10× greater than previous studies). At flow rates <7m per day, the toluene and octane recoveries were approximately 84.9 and 88.1 % , respectively, which are considered impressive as no optimization was even attempted.