DNAPL mass transfer and permeability reduction during in situ chemical oxidation with permanganate



[1] This study utilized a series of laboratory experiments to examine the DNAPL mass removal rate and permeability reduction during ISCO using permanganate (MnO4). Results show that MnO4 oxidation is effective in removing residual DNAPL from a porous medium. The DNAPL mass removal rate correlated positively with both the hydraulic stress and the oxidant load. A power relationship model of DNAPL mass removal under ISCO was proposed. Results also show that oxidation by-products CO2(g) and Mn oxide can cause pore plugging and flow by-passing. The reduction in hydraulic conductivity due to the Mn oxide precipitates was quantified. Hydraulic conductivity reduction as high as 80% was observed for oxidizing a small quantity of TCE.