Minerals recovery from CSIR acid mine drainage treatment plant and their possible uses

Abstract

The purpose of this work was to explore the mechanisms and efficacy of the selective recovery of high-concentration goethite, hematite, magnetite, gypsum, and limestone from raw AMD using magnesite, soda ash and lime at a pilot-scale process, as well as determine the feasibility of the recovered minerals for larger-scale applications. The mining industry has been recently enforcing principles of sustainable mining. This has resulted in a paradigm shift towards reducing the volume of sludge generated as well as the operating cost and improving AMD treatment efficiency. In light of that, the CSIR through its long-term strategy and patented technology has developed a hybrid system for AMD treatment and valuable minerals recovery. This technology has advanced significantly and the concept has been demonstrated on a 20 kL/day plant. The current work focuses on the recovery of valuable minerals such as goethite, hematite, magnetite and gypsum at full pilot scale, hereafter advocating for a circular economy.