The potential of reprocessing Au and by-products from a tailing dam in the Iron Quadrangle – The case of the Cuiaba Dam, Sabará, Minas Gerais

Abstract

As historical mine wastes have accumulated in storage facilities, the interest in studying the reuse of gold (Au) mining tailings has increased, yielding environmental and economic benefits. In the present study, a detailed evaluation of the Cuiaba tailing dam in Sabará, Minas Gerais (Brazil) was performed, answering a new legal framework and agreeing with a circular economy philosophy. The mineralogical analyses revealed that most associations include silicate minerals. In accordance, the Au recovery results reached values below 50%. Because of this, other potential reuse experiments, in addition to Au reprocessing, were conducted. The first product was produced from a particle size partition above 20 µm. Due to the silica concentration, this product became a fine aggregate for the construction sector. Another alternative is generating a pozzolanic product obtained by calcination, which has an application in the cement industry.