Mathematical simulation of chlorinated ethene concentration rebound after in situ chemical oxidation.
Permanganates have been used for in situ chemical oxidation (ISCO) projects since the 1990s. Unfortunately, there has been very little research performed on the phenomenon of concentration rebound after ISCO. Most research on ISCO has focused on demonstrating effectiveness, estimating kinetics, or quantifying the effects of reaction products. Only one study has demonstrated that a correlation between concentration rebound and hydrogeological parameters exists. Our study uses a numerical solution to an advection-dispersion-reaction equation to quantify a correlation between the rate of concentration rebound and molecular diffusivity in pure water. It accomplishes this by simulating a variety of sites contaminated with chlorinated ethenes that also had an ISCO with permanganate. Each simulation included advection, two-dimensional dispersion, oxidation, concentration rebound, natural oxidant demand, and retardation. Five sites were suitable for simulation and eight cells were delineated within the five sites. These cells allowed for a variety of soils, contaminants, injection methods (i.e. frequency, depth, mass of oxidant, duration, etc…), time scales, spatial scales, and hydrogeological variables to be examined. A robust correlation (R(2) = 0.92) was identified with a regression analysis between the molecular diffusion coefficient in pure water and the rate of concentration rebound.
a Haley & Aldrich, Inc. , Parsippany , New Jersey , USA.
Adam
A
Tressler
Christopher
C
Uchrin
D005030:Ethylenes / Q000737:chemistry*; D054879:Halogenation; D007700:Kinetics; D008962:Models, Theoretical; D010084:Oxidation-Reduction; D012989:Soil Pollutants / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D005030:Ethylenes; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; C036216:ethylene
ISCO; In situ chemical oxidation; concentration rebound; molecular diffusivity in water; numerical simulation