Surfactants enhancing removal

Surfactant-Enhanced Removal of Hydrophobic Oils from Source Zones... 

Surfactant-Enhanced Removal ofHydrophobic Oils from Source Zones 247... 

Surfactant-Enhanced Removal ofHydro-phobic Oils from Source Zones 251... 

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). 

Scheibenbogen, K., Zytner, R. G., Lee, H. Trevors, J. T. (1994). Enhanced removal of selected hydrocarbons from soil by Pseudomonas aeruginosa UG2 biosurfactants and some chemical surfactants. Journal of Chemical Technology and Biotechnology, 59, 53—9-... 

One of the major focuses of the in situ use of surfactants is to accelerate the removal or degradation of free-phase products (DNAPL or oil globules) as variations of technologies used in the oil industry for enhanced tertiary oil recovery as described by Hill et al. (1973)- Such in situ remediation efforts often fail, however, primarily because of differences in the goals and expectations of the applications. For example, the enhanced oil recovery industry is often satisfied with > 30% enhanced removal whereas the remediation industry often strives for >99% removal in order to meet remedial guidelines. Unfortunately, removal of about 50% of the free product (i.e., DNAPL) at a PAH-contaminated site appears to represent the full extent of practical field expectations. 

Fountain, J.C. Waddell-Sheets, C., Lagowski, A., Taylor, C., Frazier, D., and Byrne, M. (1995). Enhanced Removal of Dense Nonaqueous Phase Liquids using Surfactants -Capabilities and Limitations from Field Trials. In Surfactant-Enhanced Subsurface Remediation, ACS Symposium Series Emerging Technologies 594, Sabatini, D.A., Knox, R.D., Harwell, J.H., (ed.), American Chemical Society, 177-190. 

Micro-foam, or colloidal gas aphrons have also been reportedly used for soil flushing in contaminated-site remediation [494—498], These also have been adapted from processes developed for enhanced oil recovery (see Section 11.2.2.2). A recent review of surfactant-enhanced soil remediation [530] lists various classes of biosurfactants, some of which have been used in enhanced oil recovery, and discusses their performance on removing different type of hydrocarbons, as well as the removal of metal contaminants such as copper and zinc. In the latter area, the application of heavy metal ion complexing surfactants to remediation of landfill and mine leachate, is showing promise [541]. 

Environmental Security Technology Certification Program, Surfactant Enhanced DNAPL Removal, ESTCP Cost and Performance Report CU-9714, U.S. Department of Defense Washington, August 2001. 

Surfactant enhancement is a technology used to remove contaminants from soils and water at hazardous waste sites. The application of surfactants enhances remediation by (a) increasing contaminant mobility and solubility, (b) decreasing the mobility of contaminants, and (c) increasing the rate of biodegradion of contaminants in soil. 

The micellar-enhanced ultrafiltration MEUF technique, based on addition of surfactants and chelating agents to complex and enhance removal of undesirable compounds, show considerable promise in membrane degumming applications. The natural substances such as phospholipids act as surfactants to form large micelles that will be rejected by the membrane. 

R. E. Saichek and K. R. Reddy, Effects of System Variables on Surfactant Enhanced Electrokinetic Removal of Polycyclic Aromatic Hydrocarbons from Clayey Soils, Environ. Technol., 24, 503-515 (2003). 

Surfactant-enhanced soil flushing is also an effective procedure for remediation of PAH-contaminated soils. The removal efficiency ofphenanthrene by this treatment was up to 90% after 25 pore volumes. The toxicological test with earthworm Eigenia foetida showed that the response of this test organism was uniform after 15 pore volumes. 

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