Abstract: A large scale tungsten-molybdenum-bismuth polymetallic ores in Hunan Province contains a large amount of fluorite. After Mo-Bi iso-flotation，Bi-S mixing flotation and tungsten “GY” flotation method at room temperature on the site， the grade of CaF₂ from roughing tailings is 20.54% and -200 mesh accounting for 82.0%. Fluorite is the major useful mineral with uneven particle size which is mainly medium-fine grain size， and closely associated with major gangue minerals such as quartz and calcite. In order to determine the recovery process of fluorite， flotation research was carried out. The results showed that with Na₂CO₃ as slurry pH regulator and slime dispersant， acidized sodium silicate as inhibitor of gangue minerals， BK410 as collector， using one-roughing， two-scavenging， six-cleaning and middles back to the closed circuit in turn， fluorite concentrate with CaF₂ grade of 93.46% and recovery of 62.13% was obtained. The fluorite recovery system determined from the experiments runs smoothly and reliably. Under the condition of CaF₂ with feeding grade of 21.20%， the concentrate of CaF₂ with grade of 90.17% and recovery rate of 59.72% was obtained. The new system not only improves the utilization rate of resources， but also creates remarkable economic benefits for enterprises.

Key words: Tailings of tungsten flotation at room temperature, Fluorite, BK410, Acidized sodium silicate, Flotation