ACID LEACHING OF COPPER IN A SATURATED POROUS MATERIAL - PARAMETER-IDENTIFICATION AND EXPERIMENTAL VALIDATION OF A 2-DIMENSIONAL TRANSPORT MODEL

In this study, a two-dimensional mathematical solute transport model i s proposed to simulate the leaching of copper ore tailings using sulfu ric acid as the leaching agent, injection wells to introduce the leach ing agent, and pumping wells to retrieve the pregnant copper leach sol ution. To calibrate the model, a tracer experiment and a leaching expe riment were performed, both under conditions of a single-direction flo w pattern established between two boundaries of constant height. These experiments enabled the model hydraulic, dispersion and reaction para meters to be determined. Validation of the model was performed by comp arison of the numerical results given by the model with experimental r esults obtained from a second leaching experiment, performed under con ditions of a radial flow pattern established through the use of four i njection wells and one pumping well and making use of the parameters e stimated previously during the calibration process, The comparison bet ween predicted and measured leaching behavior was good (20-22% error). The study has significant implications for applications related to th e use of the proposed numerical model for predicting the performance o f in-situ soil washing alternatives. (C) 1997 Elsevier Science B.V.