Use of Sodium Hexametaphosphate and Citric Acid Mixture as Depressant in the Flotation Separation of Scheelite from Calcite

Laboratory Testing of Scheelite Flotation from Raw Ore in Sangdong Mine for Process Development

Tungsten is an essential metal for the manufacture of special alloys, which is in constant demand due to the development of the industry. The recovery of scheelite from undeveloped tungsten ore in South Korea was investigated to improve the flotation performance for high grade and recovery of concentrate. To investigate the interaction between the flotation reagents and the minerals, the adsorption experiments of oleic acid as a collector on Ca-bearing minerals, such as scheelite, calcite, and fluorite were carried out. This reaction was confirmed chemical adsorption by analysis of zeta potential and FTIR analysis. The batch test was performed using a raw ore to enhance the grade and recovery of the scheelite concentrate. It was obtained at the optimal conditions for high WO3 grade and recovery of scheelite concentrate by using a simple process. In particular, the sodium carbonate used as a pH modifier was investigated to increase scheelite flotation performance by supporting the selective depression of Ca-bearing gangue minerals. Furthermore, a locked cycle test (LCT) was carried out based on batch test results for the design of a continuous pilot plant.