A model of oxidation in pyritic mine wastes: part 1 equations and approximate solution

A set of equations is formulated to model the way in which oxidation proceeds in a mass of pyritic mine wastes. The model assumes that the oxidation rae is limited by the rate that oxygen is supplied to oxidation sites within the particles comprising the wastes. Oxygen supply is assumed to be by diffusion through the pore space of the wastes followed by diffusion into a moving reaction front within the particles. An approximation is made which simplifies the equations and paves the way for solution. A further approximation is made that allows an analytical solution to be constructed. The results predicted by this analytical solution are compared with the predictions of a simpler model.