Application of sugar foam to a pyrite-contaminated soil

Abstract

Mining and mineral processing of sulphide ore deposits produce large quantities of wastes, most of which are characterised as toxic or hazardous, due to the formation of acid drainage, and to their heavy metal content. Samples of pyrite-contaminated soil from a former flotation plant were studied in this work to obtain environmental characterization and rehabilitation. Acid mine drainage prediction by the standard acid base accounting method (ABA) together with speciation techniques, were used in order to determine the potential pollution of the area. The effectiveness of sugar foam as an amendment in preventing acid drainage and metal dissolution was tested in this work. The application of sugar foam results in a neutralizing action, due to the contained calcium carbonate, and in pyrite oxidation inhibition, significantly reducing acid generation and metals release.