Recovery of dodecane, octane and toluene spills in sandpacks using ethanol

This paper is an extension of the work of Grubb et al. on the recovery of lighter-than-water non aqueous phase liquids (LNAPLs) from sandpacks. Dodecane, toluene and octane (500 mL 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 (10x greater than previous studies). At flow rates < 7 m 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.