A field trial to assess the performance of CO2-supersaturated water injection for residual volatile LNAPL recovery.
A pilot scale field trial was conducted to evaluate the recovery of volatile, light non-aqueous phase liquids (LNAPLs) using a novel remediation method termed supersaturated water injection (SWI). SWI uses a patented technology to efficiently dissolve high concentrations of CO(2) into water at elevated pressures. This water is injected into the subsurface resulting in the nucleation of CO(2) bubbles at and away from the injection point. The nucleating bubbles coalesce, rise and volatilize residual LNAPL ganglia. In this study, an LNAPL composed of 103 kg of volatile pentane and hexane, and 30 kg of non-volatile Soltrol was emplaced below the water table at residual saturation. The SWI technology removed 78% of the pentane and 50% of the less volatile hexane. Contaminant mass was still being removed when the system was shut down for practical reasons. The mass removed is comparable to that expected for air sparging but a much smaller volume of gas was injected using the SWI system.
Nelson
Leif
L
Ontario Ministry of the Environment, 331 - 435 James St S, Thunder Bay, ON, Canada P7E 6S7. leifcnelson@gmail.com
Barker
James
J
Li
Tom
T
Thomson
Neil
N
Ioannidis
Mario
M
Chatzis
John
J
D002245:Carbon Dioxide / Q000737:chemistry*; D010865:Pilot Projects; D012987:Soil / Q000032:analysis; D055549:Volatile Organic Compounds / Q000737:chemistry*; D014835:Volatilization; D014873:Water Pollutants / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
D012987:Soil; D055549:Volatile Organic Compounds; D014873:Water Pollutants; D002245:Carbon Dioxide