An improved model of continuous leaching systems using segregation approach

In this study, a simplified dissolution model has been developed to evaluate the performance of continuous leaching reactors. The model considers continuous reduction of the surface area of particles using the distribution of their size and residence time. The model was validated by the bioleaching of a pyrite-arsenopyrite concentrate in the pilot plant scale, which resulted in good agreement between the experimental data and the predicted values. The developed model was also used to predict the outlet mass density function of particles, whose results showed that the mean particle size would not necessarily decrease as the mean residence time in the leaching process decreased. Using this model, the effect of operating parameters (e.g., particle size distribution, inlet flow, reagent concentration, kinetic parameters, and the type of residence time distribution) on the reactor performance can be predicted. Therefore, the model can be used for dynamic and static analyses of leaching circuits as well as designing and optimizing the processing plants.