Method for preparing manganese sulfate monohydrate by desulfurizing fume with middle-low grade manganese dioxide ore

摘要

A method for preparing manganese sulfate monohydrate by desulfurizing fume with middle-low grade manganese dioxide ore, which includes: preparing a slurry by using middle-low grade manganese dioxide ore powder, putting sulfur-containing fume in an absorbing device and controlling gas velocity and gas-liquid ratio, and then adding manganese dioxide slurry and controlling the slurry to backwards flow relative to the sulfur-containing fume, discharging the desulfurized fume from the absorbing device, pressure-filtering and separating the slurry discharged from the absorbing device, recycling the mother liquor to the absorbing device, and continuing the recycling operation until the manganese sulfate in the mother liquor is =200 g/l, the obtained filter cake at 60-70° C., adjusting pH value of the clear solution obtained to 2-4, adding manganese sulfide under agitation at 25-95° C., and removing impurities, continuing agitating, pressure-filtering and separating, vaporizing the obtained clear filtrate, and obtaining manganese sulfate monohydrate after drying in the air stream.