Biological Removal of Anorganic Pollutants from Acid Mine Drainage

Abstract

Acid Mine Drainage (AMD) is one of the significant environmental and financial liabilities of the mining industry. Currently active mines, as well as mines that have been out of production for years, produce acidic waters with high concentration of sulphates and heavy metals. Treatment methods used to mitigate impact of AMD on the environment are focused on neutralizing, stabilizing and removing pollutants through various physical, chemical and biological processes. This paper reports the results of anorganic pollutants removal from AMD using sulphate reducing bacteria (SRB). Hydrogen sulphide produced by SRB for recovery of Cu and Zn has been used in the course of selective sequential precipitation process (SSP). In the next stage sulphates were removed from AMD by the biological anaerobic reduction. Thus, by this method removing of metals and sulphates has been achieved in successive discrete steps. The experiments were performed at laboratory condition using water collected from the site of the AMD outflow at the shaft Pech from the enclosed and flooded Smolnik sulphidic deposit (Slovakia).