Abstract
Nitrate removal enhancement by applying weak electric potential to the soil near the subsurface drainage in the field was theoretically investigated for numerical modeling. Ion movement in soils under simultaneous influence of hydraulic, electrical and chemical gradient was applied to investigate the capability of the nitrate removal enhancement through subsurface drainage system. The nitrate ion transportation equation was developed utilizing non-equilibrium thermodynamics. Onsagar's reciprocal relations were applied to reduce the number of linear phenomenological coefficients that relate applied driving forces (gradients) to fluxes. Then the coefficients were expressed using measurable or known physical, electrical and chemical properties of nitrate and porous media. Primary simulation results based on the derived equations were also shown by comparison of analytic solution of advection diffusion equation.
