A Novel Process of Tungsten Flotation for Sustainable Exploitation of Tungsten Resources

Abstract

Tungsten as key metal in various fields is indispensable metal resource for global economy. Sustainable exploitation of tungsten resources is still challenging. This work makes attempt to solve the difficulty in flotation separation of tungsten minerals from Yaogangxian tungsten ore. Systematical analysis of mineralogical properties of tungsten ore was performed. A process for tungsten flotation from tungsten ore was developed for exploitation of tungsten resources. The major valuable element in the ore is tungsten, and the grade of tungsten is 0.22%. The distribution of scheelite is nonuniform, and it is majorly distributed in 0.02~0.32 mm. The intergrowth and inclusion of scheelite occur with other minerals such as calcite, diopside, grossularite, and fluorite. The liberation of scheelite reaches 92.40% for -0.074 mm accounting for 75.48%. Process factors including Na2CO3, flotation collector, modified sodium silicate solution, and lead nitrate are studied, and the optimized conditions are Na2CO3 1600 g/t, GY-107 (640 g/t for roughing and 240 g/t for scavenging), modified sodium silicate solution 4200 g/t, and lead nitrate 400 g/t. The open-circuit and closed-circuit flotation processes for tungsten separation are designed, and it is verified for effective separation of tungsten minerals. For the closed-circuit flotation, the grade of tungsten concentrate is 7.30%, while the recovery reaches 85.89%. This work provides technical insights into tungsten separation from tungsten ore.