Reverse calcite flotation applied for the beneficiation of the Queguay Formation limestone

Abstract

Limestone is a significant resource for the Uruguayan mining industry. The Queguay Formation hosts a sedimentary limestone deposit containing quartz inclusions as its primary impurity, which limits its use in applications other than cement. In this work, a representative sample from Queguay Formation was characterized and subjected to flotation tests. The application of reverse froth flotation is proposed to reject quartz from the sample. A specific reagent scheme, with fatty amines as collectors and starch as depressor was evaluated through microflotation and bench scale flotation. Microflotation test results evidenced the selectiveness of the process. Bench scale tests presented new practical challenges, which are discussed in this work.