关键词: 金尾矿, 磁选, 浮选, SiO₂

Abstract: China's annual emissions of gold tailings are huge， not only causing waste of resources， but also seriously threatening the ecological environment. SiO2 content in gold tailings in Kuancheng， Hebei is 68.64%. In order to make full use of the secondary resources of tailings， the pre-sedimentation deslimation-high intensity magnetic separation iron removal-reverse flotation iron removal-SiO₂ purification process was conducted. The results show that: under the condition of the settling time of 2.5 min settlement for desliming， grit under the condition of the magnetic field intensity of 1.2 T high intensity magnetic separation to remove iron， SiO₂ content increased from 73.38% to 73.38%， Fe₂O₃ content decreased from 5.24% to 5.24%， and the non-magnetic product using YS as collector to remove iron by reverse flotation， Fe₂O₃ content reduced to 0.51%， and then using YG-01 and YG-02 as combined collector via one roughing two cleaning quartz purification flotation， impurities had not been detected from XRD analysis on the purified product products， and its SiO₂ content is 98.46%， Al₂O₃ content reduced to 0.65%， and Fe₂O₃ content reduced to 0.09%， which can reach the state second grade quality standard of glass raw materials. SiO₂ extraction for gold tailings not only makes full use of tailing resources， but also achieves certain economic benefits.

Key words: Gold tailings, Magnetic separation, Flotation, SiO2