Effective distribution of emulsified edible oil for enhanced anaerobic bioremediation.
Recent laboratory and field studies have shown that injection of emulsified edible oils can provide an effective, low-cost alternative for stimulating anaerobic biodegradation processes. A pilot-scale permeable reactive bio-barrier (PRBB) was installed at a perchlorate and chlorinated solvent impacted site by injecting 380 L of commercially available emulsion (EOS) containing emulsified soybean oil, food-grade surfactants, lactate, and yeast extract through ten direct push injection wells over a two day period. Soil cores collected six months after emulsion injection indicate the oil was distributed up to 5 m downgradient of the injection wells. A previously developed emulsion transport model was used to simulate emulsion transport and retention using independently estimated model parameters. While there was considerable variability in the soil sampling results, the model simulations generally agreed with the observed oil distribution at the field site. Model sensitivity analyses indicate that increasing the injection flow rate or diluting the oil with more water will have little effect on final oil distribution in the aquifer. The only effective approach for enhancing the spread of emulsified oil away from the injection well appears to be injecting a greater mass of oil.
North Carolina State University, Campus Box 7908, Raleigh, NC 27695, USA. rcborden@eos.ncsu.edu
Robert C
RC
Borden
D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D004655:Emulsions / Q000737:chemistry*; D006843:Hydrocarbons, Chlorinated / Q000737:chemistry; D007773:Lactates; D010472:Perchlorates / Q000737:chemistry; D012989:Soil Pollutants / Q000302:isolation & purification / Q000378:metabolism*; D012997:Solvents / Q000737:chemistry; D013024:Soybean Oil; D013501:Surface-Active Agents; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000302:isolation & purification / Q000378:metabolism*; D018508:Water Purification / Q000191:economics / Q000379:methods*; D015003:Yeasts
D004655:Emulsions; D006843:Hydrocarbons, Chlorinated; D007773:Lactates; D010472:Perchlorates; D012989:Soil Pollutants; D012997:Solvents; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical; D013024:Soybean Oil; C494474:perchlorate