Experimental Study on Comprehensive Recovery of Quartz and Feldspar from a Tailings of Tungsten and Tin Gravity Separation in Jiangxi

According to the characteristics of high content of quartz, feldspar and mica in the tailings of tungsten and tin gravity separation from Jiangxi Province, a fluoride-free and less acid process of grinding-iron removal by magnetic separation-desliming-mica floatation-quartz and feldspar flotation separation was adopted to comprehensively recover quartz and feldspar. Magnetic separation was carried out with the sample grinding fineness of −0.074 mm content 73% and the magnetic field intensity of 1.0 T, following the fine mud of −0.020 mm removed by static-siphon method for non-magnetic products. Furthermore, the mica was floated using a combination of YF-1 (240 g/t) and dodecylamine (80 g/t) as collectors while the slurry pH was adjusted to 10.5 by Na₂CO₃. Subsequently, quartz and feldspar were separated from mica flotation tailings using Ba²⁺ as the activator of quartz (120 g/t), YF-2 as the inhibitor of feldspar (250 g/t), and YF-1 as the collector (250 g/t). The flotation tailings was feldspar concentrate, and the flotation concentrate was further separated to obtain the quartz concentrate and feldspar by-products by reverse flotation feldspar process under acidic conditions. The yield of quartz concentrate was 25.30% with a SiO₂ content of 99.20%, and the recovery rate of quartz mineral was 50%. Additionally, the yield of feldspar concentrate was 22.69% with K₂O+Na₂O content of 13.16%, while the yield of feldspar by-products was 7.68% with the content of K₂O+Na₂O of 9.23%, and the total recovery of feldspar mineral was 79%. The yield of mica concentrate was 14.50%, with K₂O, Na₂O, and Al₂O₃ content of 7.65%, 1.65%, and 16.40%, respectively. The recovery rate of mica mineral was 85%.