Prediction of Ion Concentration in The Effluent during Permeation of Acid Solutions Including Multiple Anionic Species into a Volcanic Ash Soil

Abstract

The prediction method of ion concentration in the effluent during permeation of acid solutions involving multiple anionic species into volcanic ash soil was examined in this study. The method for prediction was composed of chemical reactions between acid solution and soil, and Mixing cell model, which approximately describe solute transport in soil. The results were summarized in the following. 1) The model could simulate well pH and monovalent anions (NO3- + Cl-) in the effluent during permeation of acid solutions involving NO3-, Cl- and SO42- into soil column. This shows that it is possible to handle sum of NO3_ and Cl- as a monovalent anion. 2) The simulation results agreed well with the measured values of pH and concentration of anions and BC2+ (sum total of Ca2+, Mg2+, K+ and Na+) in the effluent. Therefore, it seemed that simulation model used in this study is useful for predicting the main effects when acid rain including multiple anionic species deposited on the Kanto loam subsoil.