A semiempirical model for bacterial growth and bioleaching of Acidithiobacillus spp.

A semiempirical model for bacterial growth and bioleaching of Acidithiobacillus spp. was developed based on the concept of transport phenomena. Only one mathematical equation and three parameters evaluated from the experimental data are required to describe the complicated bioleaching process, regardless of the source and concentration of the microorganism, the concentration, composition, and physical characteristics (particle size, shape, distribution, and porosity, etc.) of the solid substrate, the concentrations of the leaching products and byproducts, and the leaching conditions (pH, temperature, agitation, etc.). In order to evaluate the semiempirical model, five kinetic models proposed previously were compared. The results of mean deviations show that our model fits their experimental data explicitly well, even better than the corresponding models. Furthermore, the semiempirical model can be successfully used to predict the bacterial growth and bioleaching behaviors in different leaching systems, i.e. direct, indirect, direct and indirect, and simultaneous leaching. (C) 2004 Elsevier B.V. All rights reserved.