Treatment requirements for acid drainage from coal storage heaps

A model is developed and verified for predicting the generation of leachate from coal storage piles that have undergone pyrite oxidation, A number of simplifying assumptions allow an exact solution to be obtained for the equations describing the transport of the oxidation products through the heap. The oxidation products are rapidly leached from the heap, with over 90% being removed in the first three holdup volumes of liquid eluted. Combining the leachate model with a model that predicts the generation of oxidation products allows an estimate to be made of the design requirements for treating such a waste stream