An Experimental Investigation of Gold Extraction and High Grade Quartz Sand Production from Quartz−Vein Gold Tailings

Currently, gold tailings are primarily utilized for recovering valuable metals and producing building materials. However, this traditional approach is being challenged due to advancements in mineral processing technologies at processing plants and the shrinking market demand for building materials. This study investigated a pathway for the comprehensive recovery of gold and quartz from flotation tailings (0.201 g/t Au) of a quartz−vein−type gold mine, aiming to achieve tailings reduction and high−value utilization. Based on the uneven distribution of gold and quartz across particle size fractions, this study proposed a process flow of "size−classified gravity separation−gold leaching from concentrate−high grade quartz sand from tailings". The effects of process conditions on separation performance were investigated. The results showed that the gold concentrate with a 4.34% yield, a 2.229 g/t Au grade, and 47.80% recovery was obtained, while the cyanide leaching rate of this gold concentrate reached 94.21%. Furthermore, high grade quartz sand with a 33.37% yield and 99.993% SiO₂ grade along with a silica sand raw material for high−purity silica micro−powder (5.52% yield, 99.993% SiO₂) were synchronously produced. The total yield of high−value products reached 43.23%, demonstrating significant tailings−reduction benefits and considerable economic benefits. This study provides valuable insights for the development and utilization of quartz−vein type gold tailings.