Impact of variable density on electrokinetic transport and mixing in porous media

Electrokinetic (EK) techniques can effectively mobilize amendments and contaminants in porous media therefore have a great potential for situ subsurface remediation of wide variety organic inorganic contaminants. However, the fundamental mechanisms governing EK applications are complex entail coupling between different flow, transport, electrostatic geochemical processes. In this study we investigate interactions density driven effects electrokinetic transport permeable compare observed dynamics with outcomes analogous scenarios which advection dispersion only mechanisms. We perform series multidimensional experiments demonstrate strong interplay Coulombic among charged species pore water density-driven during electrokinetics. Our illuminates non-trivial composition macroscopic behavior variable dye tracer plumes, showing sinking floating patterns, distinct plume shapes spreading, as well extent mixing depending on chemical water. A numerical model, based Nernst-Planck-Poisson formulation code PHREEQC, was developed to simulate flow update aqueous solution resulting from all injected surrounding electrolyte. The model allowed us interpret visualize impact small gradients tracer. highlight importance also where not influence concentration but affect result behavior, radically ones generated advective-dispersive transport.