Abstract

Lab-scale experiments were conducted to evaluate the effect of surface tension reduction in the extension of the influence zoneand the VOC removal efficiency of ground water sparging. A glass column packed with coarse sand was used for VOC removal test at two different surface tensions. A glass column without porous media was also used for control purpose prior to sand-packed column test. A quasi-two-dimensional glass box model, packed with a sand, was used for sparging zone tests at different water surface tensions. Surface tension of the aquoues solution used in this study was controlled using sodium dodecyl sulfate (SDS). For the glass, sand column experiments, total amount of air filled in the media increased as surface tension decreased. Toluene (used as VOC in this study) removal rate increased slightly with decreased tension for both free water column and sand-packed column. Air sparging zone extended up to 500% as the surface tension decreased. Combining the results from two different experiments. VOC removal efficiency is expected to increase significantly with surface tension reduction.

Keywords

surfactant, air sparging, VOC, groundwater, remediation