130 likes | 300 Views
Surfactant Flushing. An Innovative Ground Water Remediation Technology. Jeffrey H. Harwell Asahi Glass Chair of Chemical Engineering The University of Oklahoma, Norman Principal, Surbec Environmental, LLC. Basics. Release NAPL from aquifer pores Direct and Indirect Food Additives
E N D
Surfactant Flushing An Innovative Ground Water Remediation Technology Jeffrey H. Harwell Asahi Glass Chair of Chemical Engineering The University of Oklahoma, Norman Principal, Surbec Environmental, LLC
Basics • Release NAPL from aquifer pores • Direct and Indirect Food Additives • Surfactants pass EPA biodegradation testing • Used throughout the United States • US patents 6,913,419 and 7,021,863
What is a surfactant? • Molecule fits between oil and water • Common and safe • Found in • Salad dressing • Toothpaste • Mouthwash • Shampoo
How does it work? • NAPLs contaminate ground water • Droplets become immobile • Trapped by surface tension • Force that traps water in a paper towel • Surfactants go to oil/water interface • Lower surface tension • Release droplets • Like removing grease from pants in laundry • Newly mobile NAPL extracted with pumps
Trapped-drop . . . becomes released …and is pumped to surface
Column Comparison Ground Water Food Surfactant Laundry Surfactant “Designer” blend of surfactants
Trapping Curves
Mobile Portion of NAPL in Pores without Surfactant System Capillary Number without Surfactant
Mobile Portion of NAPL in Pores with Surfactant System Capillary Number with Surfactant System Capillary Number without Surfactant
Observations • Trapped NAPL can be mobilized by • increasing water pore velocity • increasing water viscosity • lowering interfacial tension • Surbec reduces interfacial tension • 3 to 4 orders of magnitude • very low concentrations (< 1wt %)
How Is It Delivered? NAPL Pool Extraction Wells Injection Wells
17.0’ IW1 IW2 IW4 IW3 SB-4 18.0’ IW5 IW6 EW1 EW2 EW3 SB-1 IW7 IW8 IW9 IW10 SB-3 IW11 IW12 SB-2 SB-5 IW13 IW14 IW15 EW6 EW4 5 PPM EW5 IW21 IW18 IW19 IW20 IW17 IW16 SB-6 IW24 IW23 EW8 IW22 EW7 EW9 IW27 IW28 IW25 IW30 IW26 IW29 EW12 IW32 IW31 EW10 EW11 Remediation Well System Layout with Well Numbers 100’ 0’ 50’
Surfactant Flushing Integrated Process AC WASTE O/W STORAGE Separator Mixer Raw S AS Disposal NAPL IW RW