Technology Research on Sodium Salt Roasting of Vanadium Slag Pellet

Roasting of vanadium slag pellets containing sodium carbonate were investigated in this paper.This technology can avoid sintering of raw materials during roasting without addition of residual slag of vanadium extraction,and substantially increases calcination efficiency of vanadium slag coupled with decrease in energy consumption.Moreover,the adverse effect of dust on the environment can be effectively relieved.The optimum process parameters are as follows:about 5 mm of pellets diameter,26% of sodium carbonate to vanadium slag and 800℃ of roasting temperature for 60 min.The immersion ratio of vanadium in clinker is more than 94% under the optimum conditions.By roasting of the vanadium slag pellets under simulating temperature program of industrial multi-hearth furnace,the immersion ratio of vanadium in solution can reach 95% and it is 92% with calculation according to vanadium content in residual slag,both of which are higher than that for traditional process.