Surfactant-enhanced aquifer remediation SEAR

Microemulsions became well known from about 1975 to 1980 because of their use ia "micellar-polymer" enhanced oil recovery (EOR) (35). This technology exploits the ultralow iaterfacial tensions that exist among top, microemulsion, and bottom phases to remove large amounts of petroleum from porous rocks, that would be unrecoverable by conventional technologies (36,37). Siace about 1990, iaterest ia the use of this property of microemulsions has shifted to the recovery of chloriaated compounds and other iadustrial solveats from shallow aquifers. The latter appHcatioa (15) is sometimes called surfactant-enhanced aquifer remediation (SEAR). 

Weerasooriya, V. Yeh, S.L. Pope, G.A. Integrated Demonstration of Surfactant-Enhanced Aquifer Remediation (SEAR) with Surfactant Regeneration and Reuse in Proc. Symp. ACS Surfactant-Based Separations, Recent Advances, American Chemical Society Washington, DC, 1998. 

Battelle Duke Engineering, Surfactant-Enhanced Aquifer Remediation (SEAR) Design Manual, Technical Report TR-2206-ENV, Naval Facilities Engineering Command Washington, April 2002. 

A new dimensionless number called the trapping number has been defined it includes both gravity and viscous forces (UTCHEM-9.0, 2000). The dependence of residual saturations on interfacial tension is modeled in UTCHEM as a function of the trapping number. This is a formulation necessary to model the combined effect of viscous and buoyancy forces in three dimensions. Buoyancy forces are much less important under enhanced oil recovery conditions than under typical surfactant-enhanced aquifer remediation (SEAR) conditions therefore, it had not been carefully considered under three-dimensional surfactant flooding held conditions. 

Weerasooriya, V., Yeh, S.L., Pope, G.A. Integrated demonstration of surfactant-enhanced aquifer remediation (SEAR) with surfactant regeneration and reuse, in Proceedings of the Symposium on Recent Advances in ACS Surfactant-based Separations, Dallas, Texas, March 29-30, 1998. 

Furthermore, the reduction of interfacial tension between the water and NAPL caused by the addition of surfactant reduces the effect of the capillary forces that entrap the NAPL. Both these mechanisms greatly enhance the ability of surfactants to recover trapped NAPLs from contaminated soils. Hence, surfactant enhanced aquifer remediation (SEAR) is a very promising technology for remediating NAPL-contami-nated soils. 

Surfactant Enhanced Aquifer Remediation. (SEAR) A remediation technology based on reservoir chemical flooding principles (micellar solubilization and/or low interfacial tension flooding) and applied to the treatment of NAPL-contaminated sods. 

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