Advances in the ambient temperature ferrite process applied to acid mine drainage treatment

Treating acid mine drainage (AMD) using ambient temperature ferrite (ATF) process is attractive but challenging due to the complex nature of AMD Solution chemistry. Calcium, associated with sulfate and ferric oxy-hydroxides, has been shown to interfere with ferrite formation. A novel process has been developed based on the use of carbonates to scavenge the soluble calcium followed by neutralization with carefully controlled solution chemistry. With this process, magnetic precipitates of spinel structure are formed from a simulated AMD within a practically feasible reaction period, while producing an environmentally safe effluent.