Ambient temperature ferrite process for acid rock drainage treatment

摘要

Acid rock drainage (ARD) is a recognized environmental challenge facing mining industriers. An ambient temperature ferrite (ATF) process has been investigated for treating ARD. Most nonferrous metal and calcium ions present in tyipical ARDs were found to be deterimental to the ATF process. Three approaches were examined, including CO_2 aeration, addition of complex agents and use of magnetic seeds. By introducing magnetic seeds in the ATF process, the interferences were minimized and all the precipitates formed with lime neutralization were magnetically reovered from a simulated ARD. The residual concentrations of major metal ions in the treated water were environmentally acceptable. The XRD pattern confirmed the spinel ferrite crystal structure of the products.