RECOVERING METHOD FOR SILICA FROM TAILING OF FLUORITE

摘要

PURPOSE:To recover high purity silica from the tailings of fluorite in a high yield by classifying the tailings and adding a pH regulator and a capturing agent to the separated and recovered coarse particle part optionally together with an activator to remove fine CaF2 particles. CONSTITUTION:The tailings of fluorite contg. 60-85% SiO2, 5-10% CaF2, 2- 5% Fe2O3 and 5-10% other components are classified to separate and recover a coarse particle part contg. =65wt% particles having 80-400 mesh. By adding a pH regulator such as NaOH and a capturing agent such as oleic acid to the coarse particle part optionally together with an activator such as CaCl2 after converting the part into a slurry having 30-20% concn. with water or warm water as required, silica is recovered by flotation. At this time, by regulating the slurry to =11.0pH, the flotation rate is enhanced. The resulting silica has =95% purity, and more than half of the tailings can be separated and recovered.