10.2190/DP8N-GA25-HH6X-9ARY DP8NGA25HH6X9ARY 3 Solute Transport in Packed Sand Columns by Colloidal Gas Aphrons: Experimental Evidence and Modeling Approach 51 66 20020509 20020509 20020509 20020509 DP8NGA25HH6X9ARY.pdf http://baywood.metapress.com/link.asp?target=contribution&id=DP8NGA25HH6X9ARY 1 P. G. Chaphalkar Dipak Roy Louisiana State University Application of microgas dispersions called colloidal gas aphrons (CGAs) in decontaminating soils is an emerging innovative technology. This study was conducted to analyze the solute transport in columns with CGA suspensions and compare that with the aqueous solution. The breakthrough curves for both solutions demonstrated early breakthrough and tailing. The mobile-immobile model (MIM) was able to describe the solute transport by both aqueous solution and CGAs in the packed sand columns. Three column lengths were used in this study. For aqueous solutions the dispersivity increased with the length of the column; however, with CGA suspension, the dispersivity decreased with column length. This indicated that due to the blocked large pores, the flow occurred through narrow channels resulting in diminishing the variation in interstitial velocity.

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