Calcified Roast-Acid Leaching of Vanadium From Vanadium Ore in Shaanxi

Recovery of vanadium by calcified roast-acid leaching was studied.The effects of particle size of ore,roasting additive,roasting temperature,roasting time,air flux and leaching conditions on leaching rate of vanadium were examined.The results show that vanadium leaching rate can reach 70%under the conditions of particle size of-100 mesh,roasting temperature of 920 ℃,using 4%CaCO3and 2%CaCl2as roasting additive,air flux of 50m3/(m2·h),roasting time of 4h,sulfuric acid dosage of 8%,liquid-to-solid ratio of 1.5∶1,two-stage countcurrent leaching at room temperature,leaching time of 3h.