Semianalytical Solutions for Multispecies Transport Coupled with a Sequential First-Order Reaction Network Using GITT Techniques

Abstract

The paper presents a semianalytical method to solve the multispecies reactive solute-transport equation coupled with a sequential first-order reaction network under spatially or temporally varying flow velocities and dispersion coefficients. This method employs the generalized integral transform technique (GITT) and general linear transformation method by Clement [2001] to transform the set of coupled multispecies reactive transport equations into a set of independent uncoupled equations and to solve these independent equations for spatially or temporally varying flow velocities and dispersion coefficients, as well for temporally varying inlet concentration. The proposed semianalytical solution is compared against previously published analytical solutions of Srinivasan and Clement [2008] and van Genuchten [1985]. We show a practical implementation of the solution to an actual field, single-well push-pull test (PPT) example designed to obtain the concentration distribution of reactants consumed and products formed at the end of the injection phase.